A new test that predicts with almost 100 per cent accuracy that a pregnant woman will not develop pre-eclampsia within the following seven days has been given the green light to be used as standard clinical practice in one of the UK's biggest acute hospital trusts.
The blood test, conducted by Oxford University Hospitals (OUH) NHS Foundation Trust at its John Radcliffe Hospital, measures the ratio of two placental factors – maternal serum soluble fms-like tyrosine kinase (sFlt-1) and placental growth factor (PlGF) – that are released into the mother's blood.
The test was developed by Roche Diagnostics, who have funded a trial conducted at the Women's Centre at the John Radcliffe Hospital.
The trial results were successful and the response from maternity staff so enthusiastic that the test has been accepted as routine clinical practice at OUH. The introduction of the test will be cost-neutral for the trust.
Pre-eclampsia is a serious disease that occurs in four per cent of all pregnancies. It causes high blood pressure, protein in the urine and oedema and can result in liver failure, kidney failure and seizures in the mother. It can lead to restricted growth in the baby and often premature delivery.
Without the test, there is no accurate method to determine who will get the disease. Currently, any patients with suspected PE are often admitted to hospital, sometimes for several days in order to make the diagnosis. PE is diagnosed by excluding all the other possible causes of high blood pressure and protein in the urine through a series of tests, which take time and cause anxiety for the mother-to-be and her family.
The trial (currently awaiting publication) was led by Dr Manu Vatish, OUH Consultant Obstetrician and Senior Clinical Fellow with the University of Oxford's Nuffield Department of Women's and Reproductive Health.
He said: "The stress experienced by mums and their families can be put into context when we see that almost 70 per cent of patients admitted don't actually have PE.
Dr Vatish added: "The standard clinical tests for pre-eclampsia, which work on the assumption that all patients are at risk, are fairly good at predicting which women could go on to develop the disease. Using the new test together with standard clinical practice, this figure rises to 100 per cent.
Tim James, OUH Head Biomedical Scientist in Clinical Biochemistry, whose laboratories carried out the tests, said: "The beauty of these tests is that they are not reliant on analysers that are only available in Oxford. The instruments are available at many hospital sites, meaning that the benefits we have demonstrated can be expanded across the UK relatively rapidly and easily, and pregnant women everywhere should be able to benefit".


This property has two units, plus a studio for extra rental income...plus two more possible studio spaces that could be developed into additional rentals. That's potential for 5 rental units.  POW is in dire need of rentals, so this a great income property.
One duplex has 3 bedrooms, 2.5 baths. The other has 2 bedrooms and 1 bath. All appliances included in both duplexes.
utilities. Walk to anywhere in town. Previously ran as a B&B for sportsmen and business travelers.
THIS IS A BANK-OWNED REPOSSED PROPERTY SOLD AS-IS. Unoccupied for about 5 years. Has settling issues along creek-side of units.


text:
How Much More Will Your Meds Cost in 2020? [VIDEOS]
Over 60 drugmakers raised prices an average of 5.8% on hundreds of drugs.
January 7, 2020 • By Trenton Straube
Happy New Year? Pharmaceutical companies kicked off 2020 with a price hike on hundreds of drugs. The average increase was 5.8%, according to an analysis by Rx Savings Solutions, report Market Watch and The Wall Street Journal.
More than 60 drug manufacturers raised prices on Wednesday, January 1. Pfizer led the pack, with an average increase of over 9% on more than 40 drugs.
The overall 2020 increase, however, is less than that seen last year, when the price of drugs rose an average of over 6%.
The increase affects the drugs' list prices, which are set by the pharmaceutical companies. In most cases, this price tag does not indicate what the consumer actually pays because it doesn't include insurance coverage, co-payments and rebates. For a look at how drug pricing works, check out the Wall Street Journal video above (note that the related article is behind a paywall).
The increases arrive in an election year and after a year during which politicians on both sides of the aisle criticized drug costs and suggested plans for lowering them. The Trump administration, for example, proposed importing drugs from Canada.
In Minneapolis, KARE 11 TV reported on the 2020 price increases; the segment above highlights Dylan Boyer, who is living with HIV and takes Biktarvy. The price of that med is rising 4.9%, according to its manufacturer, Gilead Sciences. The increase, Gilead told the channel, reflects "the rising costs of goods and services necessary to produce groundbreaking medicines."
#co-pay
#drug pricing
#Gilead Sciences
#health insurance
#Pfizer
#treatment access
#Videos
Breast Cancer Survival Differs Dramatically by Where People Live
Cancer Patients Benefit From COVID-19 Vaccine Boosters
Trodelvy Improves Survival and Quality of Life for People With Triple-Negative Breast Cancer
Rachel Maddow Reveals She Has Skin Cancer [VIDEO]

redpajama_set_name: RedPajamaCommonCrawl


Life has a funny way of helping you find your true calling when you take the time to listen and follow the choices you are given.
That's how World Tour happened. The original goal was to build an overland trailer and prep my personal Jeep to travel from Anchorage Alaska to South America. I rented a Commercial space in Odenton, MD to build a trailer capable of carrying the extra gear I would need to live out of it while I made the long journey. I had decided to build my own trailer after I couldn't find one that would be suitable for thousands of miles of dirt roads. Constant vibration rattles the average trailer apart and when you are trying to travel completely self sufficient that just wouldn't do.
Somewhere along the way to building that trailer and preparing for the trip we took an unexpected turn. With all my tools and welding equipment in one place for the first time in 10 years I was able to create and build not just for myself but for others. We started hosting club wrenching parties. Seeing what products were out there and what needed done in the marketplace evolved into seeing a need for a different type of off road shop. A shop that could go beyond just bolting on a lift kit.With my background in machining I feel it gives us a leg up on our competition when it comes to modifying and welding. We work to a level of precision that others don't understand and are not capable of matching.
After working and building our brand life and other career changes made me want to work closer to home. To spend more time near friends and family we moved the shop to Annapolis and decided to make it a full time business which turned World Tour Off Road into what it is today.
We have grown far beyond our original goal. We now specialize in every aspect of your off road vehicle. From simple bolt on parts to custom modifications to suit your every need. Come see us so we can take your dream and turn it into structure and steel.


text:
Phone towers group Cellnex to step up pace of M&A in 2019
MADRID, Feb 22 (Reuters) - Telecom group Cellnex could bid for CTIL Tower Infrastructure, a Telefonica and Vodafone joint venture, if they put it up for sale, the Spanish company's CEO said on Friday.
"In the United Kingdom, I think it's public that there is one company that is CTIL, which is owned 50 pct by Telefonica and 50 pct by Vodafone, and they have publicly stated that they want to sell it," CEO Tobias Martinez said at a news conference. "Of course we would be interested in analysing it, it fits perfectly in our strategy."
Cellnex, which already has 23,400 tower sites after adding 8,000 sites since 2015 through M&A deals, is looking for ways to grow further in its six main markets (Spain, France, Netherlands, UK, Italy and Switzerland).
"There are deals coming in the six countries where we have presence," said Martinez said.
The company, which reported an 18 percent core profit rise in 2018, wants to buy controlling stakes and has said there are different options to finance the new investments, including raising capital from shareholders.
ConnecT, main shareholder of Cellnex with a 29.9 pct stake, has stated that it will support the company's growth strategy.
"Cellnex will buy something new. We hope this year we will buy something," said on Friday Cellnex chief financial officer Jose Manuel Aisa.
Vodafone and Telefonica said last month they would explore "potential monetisation" of their joint venture.
The two companies said in a statement they were "exploring options around their future transmission operating model which could drive synergies in the investment and operation of their end-to-end networks" in Britain. (Reporting by Andres Gonzalez, editing by Jane Merriman)


Tibetan monks protest outside the Rongwo Gonchen Monastery in Qinghai's Rebkong county where the self-immolation occurred, March 14, 2012.
A Tibetan monk set himself ablaze Wednesday at his monastery in China's northwestern Qinghai province following protests by several thousand Tibetan students calling for education reforms, sources said.
The self-immolation occurred at a monastery in Qinghai's Rebkong (in Chinese, Tongren) county in Malho (in Chinese, Huangnan) Tibetan Autonomous Prefecture, triggering protests by hundreds against Chinese rule in Tibetan-populated areas, exile sources said.
The burning came a day after nearly 4,000 middle school students held protests demanding Tibetan language and other rights in Rebkong and in neighboring Tsekhog (in Chinese, Zeku) county, sources inside Tibet said.
Rebkong was the scene of constant student protests in October 2010 against a proposed change in the language of instruction in schools from Tibetan to Chinese.
The self-immolation on Wednesday was the 28th by Tibetans since they began a wave of fiery protests in February 2009 to challenge Beijing's rule and call for the return of Tibet's exiled spiritual leader the Dalai Lama.
In the latest incident, 34-year-old monk Jamyang Palden set fire to himself at around 10.30 a.m. local time at the prayer-hall grounds of the Rongwo Gonchen Monastery in Rebkong, a Tibetan living in exile told RFA after talking to contacts in the region.
Chinese security forces surrounded the monastery and tried to disperse hundreds of Tibetans who had gathered for prayers and to protest Chinese rule, but the crowd refused to disperse.
"When the self-immolation took place, there were not many people in the area. All the monks were busy with prayers inside the monastery," the Tibetan said.
Chinese police and several Tibetans took the monk to the local hospital for treatment but fellow monks who learned of the self-immolation brought him back to the monastery, the Tibetan said.
Details concerning his condition were not immediately available.
A couple of hours later, hundreds of Tibetans converged at the monastery to protest, drawing Chinese security forces.
"Around 11 a.m. or 12 p.m., local Tibetans gathered on the grounds in front of the monastery and raised slogans. They recited prayers for the Dalai Lama and remained firmly at the site," another Tibetan exile source said.
"The local police ordered them not to recite prayers and to disperse, but the crowd refused," the source said.
The latest self-immolation occurred four days after Uprising Day, the politically sensitive March 10 anniversary of the 1959 flight into exile of the Dalai Lama and of regionwide protests throughout Tibet in 2008.
Tibet's India-based exile cabinet marked this year's March 10 anniversary of the failed 1959 national uprising against Chinese rule with a statement noting what it called China's efforts over the last half-century "to annihilate the Tibetan people and its culture."
Lobsang Sangay, the head of the exile government, said that while he strongly discourages self-immolations, the "fault lies squarely with the hardline leaders in Beijing."
The Chinese government has blamed the Dalai Lama for the self-immolations, accusing the 76-year-old Buddhist leader and his followers of plotting to create "turmoil" in China's Tibetan-inhabited areas.
But Sangay said "the self-immolations are an emphatic rejection of the empty promises of [China's] so-called 'socialist paradise'" and the lack of ability to protest in any other way in Tibet.
"Today, there is no space for any conventional protests such as hunger strikes, demonstrations and even peaceful gatherings in Tibet," Sangay said.
"Tibetans are therefore taking extreme actions such as ... [committing] self-immolations," Sangay said.
Reported by Lobe Socktsang and Soepa Gyatso for RFA's Tibetan service. Translated by Karma Dorjee. Written in English by Parameswaran Ponnudurai.


text:
They Did Their Duty with Honor, Now It Is Our Duty to Honor Them
What started in the Spring of 2003 as one man's desire to honor those Americans who had died since September 2001 in Afghanistan and Iraq, soon grew into an entire community expressing its heartfelt gratitude to those who made the ultimate sacrifice in service to our nation in those conflicts.
That grassroots group of citizens pledged to keep remembering and honoring the Fallen Heroes and forged a partnership with the City of Irvine to create a permanent memorial to accomplish that goal. The permanent Northwood Gratitude and Honor Memorial was dedicated in a ceremony on November 14, 2010.
About Irvine
Irvine is a city of 217,000 nestled against the foothills of the Santa Ana Mountain range, located 40 miles south of Los Angeles, California and 10 minutes south of Anaheim (home to Disneyland). Once a farming and citrus growing area, Irvine is now a regional business center and home to the University of California-Irvine, and numerous high technology and financial services companies. Incorporated in 1971 as the nation's largest planned community, it regularly ranks high in the U.S. for its liveability, diversity, and safety.
Irvine's history with the military dates back to WWII when the Navy opened a blimp port (still standing) and USMC Air Station El Toro bordering on what would become Irvine. These bases remained in operation until 1999 and Irvine was home to many Marines and sailors. Thirty minutes south of Irvine is USMC Camp Pendleton - home of the 2nd Battalion, 11th Marine Regiment, 1st Marine Division (2/11), which was officially adopted by the city on September 15, 2007.
The residents of Irvine and Orange County have a long held respect for our military and are committed to honoring and remembering with gratitude those who have sacrificed their lives for the nation.
Copyright 2020 by Northwood Gratitude and Honor Memorial, Inc.
Web Content Management by DNN


Is it fall yet? Lord knows I am ready for all of the sweaters and pumpkin spice I can get my hands on. In today's post we are going to dive into why fall is my favorite fashion season.
First thing first, layering!!! In fall you can change up all of your pieces in your closet by layering them on top of each other. As well as styling them in ways that if you tried to do in summer you're liable to fall out due to overheating. I'll definitely be showing you all different ways to layer pieces together that you would have never guessed to in future posts!
Second knitwear is the best thing ever its like wearing a blanket but its a lot more socially acceptable. You can literally get anything in a knit style from a skirt to your most basic of pieces such as a scarf. I love wearing fitted knitted dresses its a quick and easy way to have a complete outfit while being warm and cozy!
Plaid!!! I love wearing plaid and it is definitely a trend I hope continues for a very long time. I own a plaid suit that I love mixing and matching with other things that are in my wardrobe. I suggest finding a plaid blazer or pant that you can wear all of the time by styling with sweaters and doing that fun layering thing I talked about. This way you have tons of outfits at little cost to you and saving money is the name of the game!
Okay so we can't forget about the footwear. I love a good boot and I do not discriminate I like western boots as well as short booties. With a boot you can wear the simplest outfit and look elevated bc the shoe is the star of the show. All boots are my friends and I am saying it loud and proud!
Overall there are so many great things about fall. All though you can't go tanning and lounge out by the pool you can snuggle up by a fire and make s'mores. That in itself is a win for me!!


text:
Mineralization of nitrogen by protozoan activity in soil
P. Kuikman
Research output: Thesis › external PhD, WU

In general, more than 95% of the nitrogen in soils is present in organic forms. This nitrogen is not directly available to plants unless microbial decomposition takes place with the release of mineral nitrogen. In modern agriculture, nitrogen is often applied to arable soils as a fertilizer to support high levels of crop production. Nitrogen is one of the essential nutrients and is required by plants in substantial amounts (1.5-5% x g -1dry weight). Extensive application of fertilizer nitrogen causes substantial environmental problems such as leaching of nitrates into groundwater which is used as drinking water and ammonia volatilization into the atmosphere. This ammonia is deposited on the surface of the earth. Nitrification then results in acidification of soils and damage to plants.
The microbial biomass in soil is both a source and a sink for nitrogen. This renders the turnover of nitrogen through the microbial biomass a key process in nitrogen cycling in soil. Knowledge about the mechanisms involved in the mineralization of nitrogen in soils is necessary to improve control of the nitrogen cycling in arable soils. Evidence is accumulating that interactions between microflora and fauna such as protozoa are responsible for a signicant portion of the mineralization of nitrogen in soils. In this thesis, the impact of protozoan predation of bacteria on the mineralization of nitrogen from bacterial cells in soil was investigated.
Traditionally, the mineralization of nitrogen in soils has been attributed to the microflora, i.e. bacteria and fungi. Protozoa have long been recognized as the major predators of bacteria thereby regulating the size of the bacterial populations in soils. The potential impact of protozoa on the mineralization of nitrogen has only recently been recognized (Elliott et al. 1979). When protozoa consume bacteria, excess nitrogen is excreted as ammonium nitrogen. This relation is based on a similar carbon:nitrogen ratio for protozoa and bacteria. Additionally, it has been hypothesized that, by grazing bacteria, protozoa enhance microbial activity and eventually mineralize nitrogen from soil organic matter (Clarholm 1985).
Experiments were carried out in microcosms containing sterilized soil that was inoculated with specific microbial populations. The turnover of the 15 N from microbial cells was assessed by growing plants on these soils and analysing the recovery of 15N in the plant. The activity of protozoa was inferred from an increased number of protozoa during the incubation period.
In Chapter 2, the impact of protozoan grazing on the mineralization of nitrogen from bacterial biomass was investigated. Soil was inoculated with the basic composition of the food chain studied, i.e. 15N-labelled Pseudomonas aeruginosa alone or with protozoa. Protozoan grazing strongly stimulated the turnover and the mineralization of bacterial nitrogen. In the presence of protozoa, plants recovered 65% more bacterial 15N than in soils without protozoa. Furthermore, the presence of protozoa resulted in a 26% higher mineralization and uptake of nitrogen from soil organic sources. Additionally, a suspension with a natural bacterial population from the soil was added to the basic composition of the food chain. An increased number of bacteria would immobilize more nitrogen. It was hypothesized that consequently protozoan grazing would exert a more pronounced effect on the mineralization of nitrogen. In this case, the presence of protozoa stimulated the mineralization and uptake by plants of nitrogen from soil organic sources by 44% compared to soils without protozoa. However, the protozoan mediated mineralization and plant uptake of 15 N from bacterial cells was reduced by the addition of the bacterial suspension. This effect was explained by assuming that internal cycling of nitrogen occurred to a larger extent due to an increased size of the bacterial population when both a bacterial suspension and 15N-labelled Pseudomonas aerughosa were added.
Soil provides a very heterogeneous environment with its network of pores with sizes from 0.2 μm to 2000μm. Microorganisms have been shown to be neither randomly nor uniformly distributed through the soil fabric (Foster 1988). Part of the habitable pore space for bacteria in soil is not accessible to protozoa (Vargas and Hattori 1986). The numbers of protozoa that are found in natural soil ranges from 1 x 10 4to 1 x 10 6per gram dry soil. Still, protozoa have to migrate through the soil matrix to meet their prey organisms. This is especially true under the experimental conditions in our microcosms where only up to 1 x 10 4protozoa per gram of dry soil have been inoculated at the start. The effect of the inoculum density of protozoa and of spatial separation of protozoa and (prey)organisms on the migration by protozoa as well as on the turnover, dynamics and transport of specific microbial populations in soil was studied (Chapter 3). The CO 2 evolution served as an indicator of microbial activity. The fate of introduced 14C-labelled bacterial cells was followed by monitoring 14C-CO 2 evolution. Two antibiotic resistant Pseudomonas fluorescens R2f strains were inoculated. The transfer of genes between
representatives of these strains via conjugation was a powerfull indicator of the distribution of bacteria and protozoa in soils. The activity of protozoa increased CO 2 evolution compared to soils not inoculated with protozoa. This stimulation of the CO 2 evolution was related to the percentage of a soil portion that was inoculated with protozoa. The inoculated number of protozoa did not affect the CO 2 evolution. This indicated that protozoa were only active in those particles into which they were inoculated. Protozoa accelerated the turnover of 14C . The more protozoa were inoculated, the faster specific 14C-labelled substrates were respired. The turnover of 14C was determined by the frequency of encounters between protozoa and labelled microorganisms. It was concluded that this frequency is a function of the concentration of protozoa and 14C-labelled microorganisms in the soil matrix. The results obtained in Chapter 3 picture the soil as a rather constrained system with respect to the mobility of both protozoa and bacteria in the soil matrix. Protozoa hardly influence the distribution of bacterial cells in soil through dispersion. Additionally, it was shown that protozoa did not affect the transfer of genes through organisms in soil. The results support the hypothesis by Stout (1973) that the activity of protozoa is confined to small spaces and consequently small populations.
Protozoa are in essence aquatic organisms and therefore water is essential to their functioning. Based an the average cell sizes of 10-50 μm for amoebae and 10-20 μm for flagellates, these protozoa can only enter and feed in pores with a pore neck diameter 3- 20 μm and larger (Darbyshire 1976). The availability of water was shown to strongly regulate the grazing activity of protozoa (Chapter 5). In soils kept at a low soil moisture tension (3 Bar), protozoa were not active. It was estimated from a water retention curve (Postma et al. 1989) that at this moisture tension, pores with pore necks larger than 3 μm are devoid of water. Hence, protozoan movement and feeding was restricted because waterfilms were too thin or even absent. Only at higher soil moisture contents (0.1 Bar and 0.3 Bar), the activity of protozoa reduced the number of bacteria and increased the mineral nitrogen content in soil (Chapter 5).
Upon drying of the soil, protozoa encyst to survive dry conditions. Little information is available on the signals and the time needed to excyst and return to trophic stages when favourable soil moisture conditions are restored. In a series of three experiments, plant water transpiration was used as an experimental tool to induce soil moisture regimes with defined fluctuations (Chapter 4 and 5). Even though protozoa were forced to encyst upon drying of the soil, they reacted very rapidly to remoistening. In soils that were incubated under conditions with modest soil moisture fluctuations, protozoan activity resulted in an even higher mineralization and plant uptake of 15N from bacterial cells than in soils that were incubated with a stable soil moisture regime. The activity of protozoa stimulated the mineralization of nitrogen from soil organic sources under all soil moisture regimes applied (Chapter 4). The protozoan activity was further restricted when soil moisture regimes were characterized by more intense and more frequently induced moisture fluctuations (Chapter 5). This was shown by a reduced recovery of bacterial nitrogen in plants compared to soils that were kept continuously moist.
The effect of protozoan predation on the mineralization of carbon and nitrogen from soil organic matter was determined simultaneously in an experiment in which plants were grown in soil microcosms that contained 14C-carbon and 15N-nitrogen organic material both in the presence and absence of protozoa (Chapter 6). The predating activity of protozoa accelerated the turnover of microbial carbon and nitrogen by reducing the size of the bacterial population. But more important, protozoa stimulated the activity of the remaining bacterial population as judged from an ongoing higher rate of 14C-CO 2 respiration in the presence of protozoa compared to sails without protozoa. Protozoa responded immediately to the restoration of favourable moisture conditions in the soils as shown by the increased rate Of 14C-CO 2 respiration. These results support the observations that protozoa numbers increased within 1 or 2 days upon the addition of water to dry soils (Hunt et al. 1989). Furthermore, it was hypothesized that the flow of water contributed to a (re)distribution of protozoa. In soils that were inoculated with less protozoa, the rewetting response in terms of increased rate of 14C-CO 2 respiration, was larger than in soils inoculated with more protozoa.
Several mechanisms for the action of protozoa with respect to mineralization of nitrogen have been proposed (Chapter l):
1) by grazing bacteria, protozoan biomass is produced at the expense of bacterial biomass and excess nitrogen is excreted as ammonium
2) by grazing bacteria, protozoa produce waste products (cell wall material and other nutrients) which in turn may enhance microbial activity
3) whilst moving through the soil searching for food particles, protozoa might (re)inoculate (new) substrates by transporting bacteria that adhere to their cell surface or by bacteria that are not digestable and therefore excreted.
In all experiments, the activity of protozoa reduced the size of the bacterial populations both in planted and in unplanted soils by a factor of two (Chapter 5 and 6), five (Chapter 3) to eight (Chapter 2). As a consequence, K is concluded that consumption of bacteria is responsible for at least a part of the increased mineralization of nitrogen in the presence of protozoa. Furthermore, the activity of protozoa induced an ongoing higher microbial respiration rate in planted soils (Chapter 6). It was demonstrated that a smaller sized bacterial population was more active in terms of the amount of carbon metabolized per unit microbial biomass when being predated upon by protozoa. Also, the presence of protozoa increased maintenance of the plasmid in a plasmid containing bacterial population.
This was attributed to an improved nutrient availability in soils where protozoa grazed bacteria. With respect to the third mechanism through which protozoa could enhance mineralization of nitrogen, only limited information was available. It was shown that in unplanted soils (Chapter 3) that are incubated under stable soil moisture regimes, the migration and mobility of protozoa between aggregates is very much restricted (Vargas and Hattori 1986). Based on the observations on gene transfer, it could not be demonstrated that protozoa are important vectors in the allocation of bacteria through soil. However, it was hypothesized that water flow significantly contributes to the distribution of protozoa and probably bacteria as well through the soil matrix.
That microorganisms are responsible for mineralization of nitrogen from organic sources in soils has long been recognized. The results, presented in this thesis, showed clearly that in soils protozoan grazing of bacteria substantially improves the availability of organically bound nitrogen to plants. The mechanisms by which protozoa stimulate the mineralization of nitrogen are i) by releasing nitrogen directly from bacterial cells and ii) by stimulating the turnover of soil organic matter through the microbial biomass. The microcosm approach proved to be useful to study the mineralization of nitrogen by protozoan activity in soil. The dynamic character of planted soil was demonstrated by an ongoing respiration of soil organic carbon. In fallow soil, the protozoan activity lasted only 10 days and then, gradually, microbial activity slowed down. However, in both planted and fallow soil, protozoa exhibited their stimulating effect on carbon and nitrogen mineralization rates. Without significant water flow through the soil matrix, the mobility and migration of protozoa is low. Reallocation of bacteria in the soil matrix was virtually absent. Hence, protozoa sec do not contribute to a (re)distribution and dispersion of bacteria through soil as hypothesized by Finlay and Fenchel (1989). Meanwhile, it was demonstrated that applying a combination of techniques from the field of microbial ecology and of genetics can substantially improve our understanding of the ecology of (introduced) soil microorganisms.
Protozoa exhibited a very fast, immediate reaction to restoration of favourable moisture conditions in previously dried soils. The pulsed addition of water to dry soils have a significant impact on the dynamics of food-chain reactions in soil in terms of microbial activity and of carbon and nitrogen mineralization. Here, the effect of protozoa could be caused both by substrates made available to microorganisms through disruption of soil aggregates or through an improved distribution of the biota through the soil. The magnitude of the effect of protozoan grazing on the plant availability of organically and bacterial bound nitrogen supports the concept that food-web interactions rather than microbial activity alone, are responsible for nitrogen mineralization in soil.
Awarding Institution
Supervisors/Advisors
Zehnder, A.J.B., Promotor
Kuikman
microbial degradation
https://edepot.wur.nl/203141
Fingerprint Dive into the research topics of 'Mineralization of nitrogen by protozoan activity in soil'. Together they form a unique fingerprint.
mineralization Earth & Environmental Sciences
nitrogen Earth & Environmental Sciences
bacterium Earth & Environmental Sciences
grazing Earth & Environmental Sciences
soil moisture regime Earth & Environmental Sciences
turnover Earth & Environmental Sciences
Kuikman, P. (1990). Mineralization of nitrogen by protozoan activity in soil. Kuikman. https://edepot.wur.nl/203141
Kuikman, P.. / Mineralization of nitrogen by protozoan activity in soil. S.l. : Kuikman, 1990. 103 p.
@phdthesis{681612b33b674c4798a07d73ee1e8fd8,
title = "Mineralization of nitrogen by protozoan activity in soil",
abstract = "In general, more than 95% of the nitrogen in soils is present in organic forms. This nitrogen is not directly available to plants unless microbial decomposition takes place with the release of mineral nitrogen. In modern agriculture, nitrogen is often applied to arable soils as a fertilizer to support high levels of crop production. Nitrogen is one of the essential nutrients and is required by plants in substantial amounts (1.5-5% x g -1dry weight). Extensive application of fertilizer nitrogen causes substantial environmental problems such as leaching of nitrates into groundwater which is used as drinking water and ammonia volatilization into the atmosphere. This ammonia is deposited on the surface of the earth. Nitrification then results in acidification of soils and damage to plants.The microbial biomass in soil is both a source and a sink for nitrogen. This renders the turnover of nitrogen through the microbial biomass a key process in nitrogen cycling in soil. Knowledge about the mechanisms involved in the mineralization of nitrogen in soils is necessary to improve control of the nitrogen cycling in arable soils. Evidence is accumulating that interactions between microflora and fauna such as protozoa are responsible for a signicant portion of the mineralization of nitrogen in soils. In this thesis, the impact of protozoan predation of bacteria on the mineralization of nitrogen from bacterial cells in soil was investigated.Traditionally, the mineralization of nitrogen in soils has been attributed to the microflora, i.e. bacteria and fungi. Protozoa have long been recognized as the major predators of bacteria thereby regulating the size of the bacterial populations in soils. The potential impact of protozoa on the mineralization of nitrogen has only recently been recognized (Elliott et al. 1979). When protozoa consume bacteria, excess nitrogen is excreted as ammonium nitrogen. This relation is based on a similar carbon:nitrogen ratio for protozoa and bacteria. Additionally, it has been hypothesized that, by grazing bacteria, protozoa enhance microbial activity and eventually mineralize nitrogen from soil organic matter (Clarholm 1985).Experiments were carried out in microcosms containing sterilized soil that was inoculated with specific microbial populations. The turnover of the 15 N from microbial cells was assessed by growing plants on these soils and analysing the recovery of 15N in the plant. The activity of protozoa was inferred from an increased number of protozoa during the incubation period.In Chapter 2, the impact of protozoan grazing on the mineralization of nitrogen from bacterial biomass was investigated. Soil was inoculated with the basic composition of the food chain studied, i.e. 15N-labelled Pseudomonas aeruginosa alone or with protozoa. Protozoan grazing strongly stimulated the turnover and the mineralization of bacterial nitrogen. In the presence of protozoa, plants recovered 65% more bacterial 15N than in soils without protozoa. Furthermore, the presence of protozoa resulted in a 26% higher mineralization and uptake of nitrogen from soil organic sources. Additionally, a suspension with a natural bacterial population from the soil was added to the basic composition of the food chain. An increased number of bacteria would immobilize more nitrogen. It was hypothesized that consequently protozoan grazing would exert a more pronounced effect on the mineralization of nitrogen. In this case, the presence of protozoa stimulated the mineralization and uptake by plants of nitrogen from soil organic sources by 44% compared to soils without protozoa. However, the protozoan mediated mineralization and plant uptake of 15 N from bacterial cells was reduced by the addition of the bacterial suspension. This effect was explained by assuming that internal cycling of nitrogen occurred to a larger extent due to an increased size of the bacterial population when both a bacterial suspension and 15N-labelled Pseudomonas aerughosa were added.Soil provides a very heterogeneous environment with its network of pores with sizes from 0.2 μm to 2000μm. Microorganisms have been shown to be neither randomly nor uniformly distributed through the soil fabric (Foster 1988). Part of the habitable pore space for bacteria in soil is not accessible to protozoa (Vargas and Hattori 1986). The numbers of protozoa that are found in natural soil ranges from 1 x 10 4to 1 x 10 6per gram dry soil. Still, protozoa have to migrate through the soil matrix to meet their prey organisms. This is especially true under the experimental conditions in our microcosms where only up to 1 x 10 4protozoa per gram of dry soil have been inoculated at the start. The effect of the inoculum density of protozoa and of spatial separation of protozoa and (prey)organisms on the migration by protozoa as well as on the turnover, dynamics and transport of specific microbial populations in soil was studied (Chapter 3). The CO 2 evolution served as an indicator of microbial activity. The fate of introduced 14C-labelled bacterial cells was followed by monitoring 14C-CO 2 evolution. Two antibiotic resistant Pseudomonas fluorescens R2f strains were inoculated. The transfer of genes betweenrepresentatives of these strains via conjugation was a powerfull indicator of the distribution of bacteria and protozoa in soils. The activity of protozoa increased CO 2 evolution compared to soils not inoculated with protozoa. This stimulation of the CO 2 evolution was related to the percentage of a soil portion that was inoculated with protozoa. The inoculated number of protozoa did not affect the CO 2 evolution. This indicated that protozoa were only active in those particles into which they were inoculated. Protozoa accelerated the turnover of 14C . The more protozoa were inoculated, the faster specific 14C-labelled substrates were respired. The turnover of 14C was determined by the frequency of encounters between protozoa and labelled microorganisms. It was concluded that this frequency is a function of the concentration of protozoa and 14C-labelled microorganisms in the soil matrix. The results obtained in Chapter 3 picture the soil as a rather constrained system with respect to the mobility of both protozoa and bacteria in the soil matrix. Protozoa hardly influence the distribution of bacterial cells in soil through dispersion. Additionally, it was shown that protozoa did not affect the transfer of genes through organisms in soil. The results support the hypothesis by Stout (1973) that the activity of protozoa is confined to small spaces and consequently small populations.Protozoa are in essence aquatic organisms and therefore water is essential to their functioning. Based an the average cell sizes of 10-50 μm for amoebae and 10-20 μm for flagellates, these protozoa can only enter and feed in pores with a pore neck diameter 3- 20 μm and larger (Darbyshire 1976). The availability of water was shown to strongly regulate the grazing activity of protozoa (Chapter 5). In soils kept at a low soil moisture tension (3 Bar), protozoa were not active. It was estimated from a water retention curve (Postma et al. 1989) that at this moisture tension, pores with pore necks larger than 3 μm are devoid of water. Hence, protozoan movement and feeding was restricted because waterfilms were too thin or even absent. Only at higher soil moisture contents (0.1 Bar and 0.3 Bar), the activity of protozoa reduced the number of bacteria and increased the mineral nitrogen content in soil (Chapter 5).Upon drying of the soil, protozoa encyst to survive dry conditions. Little information is available on the signals and the time needed to excyst and return to trophic stages when favourable soil moisture conditions are restored. In a series of three experiments, plant water transpiration was used as an experimental tool to induce soil moisture regimes with defined fluctuations (Chapter 4 and 5). Even though protozoa were forced to encyst upon drying of the soil, they reacted very rapidly to remoistening. In soils that were incubated under conditions with modest soil moisture fluctuations, protozoan activity resulted in an even higher mineralization and plant uptake of 15N from bacterial cells than in soils that were incubated with a stable soil moisture regime. The activity of protozoa stimulated the mineralization of nitrogen from soil organic sources under all soil moisture regimes applied (Chapter 4). The protozoan activity was further restricted when soil moisture regimes were characterized by more intense and more frequently induced moisture fluctuations (Chapter 5). This was shown by a reduced recovery of bacterial nitrogen in plants compared to soils that were kept continuously moist.The effect of protozoan predation on the mineralization of carbon and nitrogen from soil organic matter was determined simultaneously in an experiment in which plants were grown in soil microcosms that contained 14C-carbon and 15N-nitrogen organic material both in the presence and absence of protozoa (Chapter 6). The predating activity of protozoa accelerated the turnover of microbial carbon and nitrogen by reducing the size of the bacterial population. But more important, protozoa stimulated the activity of the remaining bacterial population as judged from an ongoing higher rate of 14C-CO 2 respiration in the presence of protozoa compared to sails without protozoa. Protozoa responded immediately to the restoration of favourable moisture conditions in the soils as shown by the increased rate Of 14C-CO 2 respiration. These results support the observations that protozoa numbers increased within 1 or 2 days upon the addition of water to dry soils (Hunt et al. 1989). Furthermore, it was hypothesized that the flow of water contributed to a (re)distribution of protozoa. In soils that were inoculated with less protozoa, the rewetting response in terms of increased rate of 14C-CO 2 respiration, was larger than in soils inoculated with more protozoa.Several mechanisms for the action of protozoa with respect to mineralization of nitrogen have been proposed (Chapter l):1) by grazing bacteria, protozoan biomass is produced at the expense of bacterial biomass and excess nitrogen is excreted as ammonium2) by grazing bacteria, protozoa produce waste products (cell wall material and other nutrients) which in turn may enhance microbial activity3) whilst moving through the soil searching for food particles, protozoa might (re)inoculate (new) substrates by transporting bacteria that adhere to their cell surface or by bacteria that are not digestable and therefore excreted.In all experiments, the activity of protozoa reduced the size of the bacterial populations both in planted and in unplanted soils by a factor of two (Chapter 5 and 6), five (Chapter 3) to eight (Chapter 2). As a consequence, K is concluded that consumption of bacteria is responsible for at least a part of the increased mineralization of nitrogen in the presence of protozoa. Furthermore, the activity of protozoa induced an ongoing higher microbial respiration rate in planted soils (Chapter 6). It was demonstrated that a smaller sized bacterial population was more active in terms of the amount of carbon metabolized per unit microbial biomass when being predated upon by protozoa. Also, the presence of protozoa increased maintenance of the plasmid in a plasmid containing bacterial population.This was attributed to an improved nutrient availability in soils where protozoa grazed bacteria. With respect to the third mechanism through which protozoa could enhance mineralization of nitrogen, only limited information was available. It was shown that in unplanted soils (Chapter 3) that are incubated under stable soil moisture regimes, the migration and mobility of protozoa between aggregates is very much restricted (Vargas and Hattori 1986). Based on the observations on gene transfer, it could not be demonstrated that protozoa are important vectors in the allocation of bacteria through soil. However, it was hypothesized that water flow significantly contributes to the distribution of protozoa and probably bacteria as well through the soil matrix.That microorganisms are responsible for mineralization of nitrogen from organic sources in soils has long been recognized. The results, presented in this thesis, showed clearly that in soils protozoan grazing of bacteria substantially improves the availability of organically bound nitrogen to plants. The mechanisms by which protozoa stimulate the mineralization of nitrogen are i) by releasing nitrogen directly from bacterial cells and ii) by stimulating the turnover of soil organic matter through the microbial biomass. The microcosm approach proved to be useful to study the mineralization of nitrogen by protozoan activity in soil. The dynamic character of planted soil was demonstrated by an ongoing respiration of soil organic carbon. In fallow soil, the protozoan activity lasted only 10 days and then, gradually, microbial activity slowed down. However, in both planted and fallow soil, protozoa exhibited their stimulating effect on carbon and nitrogen mineralization rates. Without significant water flow through the soil matrix, the mobility and migration of protozoa is low. Reallocation of bacteria in the soil matrix was virtually absent. Hence, protozoa sec do not contribute to a (re)distribution and dispersion of bacteria through soil as hypothesized by Finlay and Fenchel (1989). Meanwhile, it was demonstrated that applying a combination of techniques from the field of microbial ecology and of genetics can substantially improve our understanding of the ecology of (introduced) soil microorganisms.Protozoa exhibited a very fast, immediate reaction to restoration of favourable moisture conditions in previously dried soils. The pulsed addition of water to dry soils have a significant impact on the dynamics of food-chain reactions in soil in terms of microbial activity and of carbon and nitrogen mineralization. Here, the effect of protozoa could be caused both by substrates made available to microorganisms through disruption of soil aggregates or through an improved distribution of the biota through the soil. The magnitude of the effect of protozoan grazing on the plant availability of organically and bacterial bound nitrogen supports the concept that food-web interactions rather than microbial activity alone, are responsible for nitrogen mineralization in soil.",
keywords = "mineralisatie, microbi{\"e}le afbraak, stikstof, microbiologie, mineralization, microbial degradation, nitrogen, microbiology",
author = "P. Kuikman",
note = "WU thesis 1331 Proefschrift Wageningen",
publisher = "Kuikman",
Kuikman, P 1990, 'Mineralization of nitrogen by protozoan activity in soil', Doctor of Philosophy, S.l.. <https://edepot.wur.nl/203141>
Mineralization of nitrogen by protozoan activity in soil. / Kuikman, P.
S.l. : Kuikman, 1990. 103 p.
TY - THES
T1 - Mineralization of nitrogen by protozoan activity in soil
AU - Kuikman, P.
N1 - WU thesis 1331 Proefschrift Wageningen
N2 - In general, more than 95% of the nitrogen in soils is present in organic forms. This nitrogen is not directly available to plants unless microbial decomposition takes place with the release of mineral nitrogen. In modern agriculture, nitrogen is often applied to arable soils as a fertilizer to support high levels of crop production. Nitrogen is one of the essential nutrients and is required by plants in substantial amounts (1.5-5% x g -1dry weight). Extensive application of fertilizer nitrogen causes substantial environmental problems such as leaching of nitrates into groundwater which is used as drinking water and ammonia volatilization into the atmosphere. This ammonia is deposited on the surface of the earth. Nitrification then results in acidification of soils and damage to plants.The microbial biomass in soil is both a source and a sink for nitrogen. This renders the turnover of nitrogen through the microbial biomass a key process in nitrogen cycling in soil. Knowledge about the mechanisms involved in the mineralization of nitrogen in soils is necessary to improve control of the nitrogen cycling in arable soils. Evidence is accumulating that interactions between microflora and fauna such as protozoa are responsible for a signicant portion of the mineralization of nitrogen in soils. In this thesis, the impact of protozoan predation of bacteria on the mineralization of nitrogen from bacterial cells in soil was investigated.Traditionally, the mineralization of nitrogen in soils has been attributed to the microflora, i.e. bacteria and fungi. Protozoa have long been recognized as the major predators of bacteria thereby regulating the size of the bacterial populations in soils. The potential impact of protozoa on the mineralization of nitrogen has only recently been recognized (Elliott et al. 1979). When protozoa consume bacteria, excess nitrogen is excreted as ammonium nitrogen. This relation is based on a similar carbon:nitrogen ratio for protozoa and bacteria. Additionally, it has been hypothesized that, by grazing bacteria, protozoa enhance microbial activity and eventually mineralize nitrogen from soil organic matter (Clarholm 1985).Experiments were carried out in microcosms containing sterilized soil that was inoculated with specific microbial populations. The turnover of the 15 N from microbial cells was assessed by growing plants on these soils and analysing the recovery of 15N in the plant. The activity of protozoa was inferred from an increased number of protozoa during the incubation period.In Chapter 2, the impact of protozoan grazing on the mineralization of nitrogen from bacterial biomass was investigated. Soil was inoculated with the basic composition of the food chain studied, i.e. 15N-labelled Pseudomonas aeruginosa alone or with protozoa. Protozoan grazing strongly stimulated the turnover and the mineralization of bacterial nitrogen. In the presence of protozoa, plants recovered 65% more bacterial 15N than in soils without protozoa. Furthermore, the presence of protozoa resulted in a 26% higher mineralization and uptake of nitrogen from soil organic sources. Additionally, a suspension with a natural bacterial population from the soil was added to the basic composition of the food chain. An increased number of bacteria would immobilize more nitrogen. It was hypothesized that consequently protozoan grazing would exert a more pronounced effect on the mineralization of nitrogen. In this case, the presence of protozoa stimulated the mineralization and uptake by plants of nitrogen from soil organic sources by 44% compared to soils without protozoa. However, the protozoan mediated mineralization and plant uptake of 15 N from bacterial cells was reduced by the addition of the bacterial suspension. This effect was explained by assuming that internal cycling of nitrogen occurred to a larger extent due to an increased size of the bacterial population when both a bacterial suspension and 15N-labelled Pseudomonas aerughosa were added.Soil provides a very heterogeneous environment with its network of pores with sizes from 0.2 μm to 2000μm. Microorganisms have been shown to be neither randomly nor uniformly distributed through the soil fabric (Foster 1988). Part of the habitable pore space for bacteria in soil is not accessible to protozoa (Vargas and Hattori 1986). The numbers of protozoa that are found in natural soil ranges from 1 x 10 4to 1 x 10 6per gram dry soil. Still, protozoa have to migrate through the soil matrix to meet their prey organisms. This is especially true under the experimental conditions in our microcosms where only up to 1 x 10 4protozoa per gram of dry soil have been inoculated at the start. The effect of the inoculum density of protozoa and of spatial separation of protozoa and (prey)organisms on the migration by protozoa as well as on the turnover, dynamics and transport of specific microbial populations in soil was studied (Chapter 3). The CO 2 evolution served as an indicator of microbial activity. The fate of introduced 14C-labelled bacterial cells was followed by monitoring 14C-CO 2 evolution. Two antibiotic resistant Pseudomonas fluorescens R2f strains were inoculated. The transfer of genes betweenrepresentatives of these strains via conjugation was a powerfull indicator of the distribution of bacteria and protozoa in soils. The activity of protozoa increased CO 2 evolution compared to soils not inoculated with protozoa. This stimulation of the CO 2 evolution was related to the percentage of a soil portion that was inoculated with protozoa. The inoculated number of protozoa did not affect the CO 2 evolution. This indicated that protozoa were only active in those particles into which they were inoculated. Protozoa accelerated the turnover of 14C . The more protozoa were inoculated, the faster specific 14C-labelled substrates were respired. The turnover of 14C was determined by the frequency of encounters between protozoa and labelled microorganisms. It was concluded that this frequency is a function of the concentration of protozoa and 14C-labelled microorganisms in the soil matrix. The results obtained in Chapter 3 picture the soil as a rather constrained system with respect to the mobility of both protozoa and bacteria in the soil matrix. Protozoa hardly influence the distribution of bacterial cells in soil through dispersion. Additionally, it was shown that protozoa did not affect the transfer of genes through organisms in soil. The results support the hypothesis by Stout (1973) that the activity of protozoa is confined to small spaces and consequently small populations.Protozoa are in essence aquatic organisms and therefore water is essential to their functioning. Based an the average cell sizes of 10-50 μm for amoebae and 10-20 μm for flagellates, these protozoa can only enter and feed in pores with a pore neck diameter 3- 20 μm and larger (Darbyshire 1976). The availability of water was shown to strongly regulate the grazing activity of protozoa (Chapter 5). In soils kept at a low soil moisture tension (3 Bar), protozoa were not active. It was estimated from a water retention curve (Postma et al. 1989) that at this moisture tension, pores with pore necks larger than 3 μm are devoid of water. Hence, protozoan movement and feeding was restricted because waterfilms were too thin or even absent. Only at higher soil moisture contents (0.1 Bar and 0.3 Bar), the activity of protozoa reduced the number of bacteria and increased the mineral nitrogen content in soil (Chapter 5).Upon drying of the soil, protozoa encyst to survive dry conditions. Little information is available on the signals and the time needed to excyst and return to trophic stages when favourable soil moisture conditions are restored. In a series of three experiments, plant water transpiration was used as an experimental tool to induce soil moisture regimes with defined fluctuations (Chapter 4 and 5). Even though protozoa were forced to encyst upon drying of the soil, they reacted very rapidly to remoistening. In soils that were incubated under conditions with modest soil moisture fluctuations, protozoan activity resulted in an even higher mineralization and plant uptake of 15N from bacterial cells than in soils that were incubated with a stable soil moisture regime. The activity of protozoa stimulated the mineralization of nitrogen from soil organic sources under all soil moisture regimes applied (Chapter 4). The protozoan activity was further restricted when soil moisture regimes were characterized by more intense and more frequently induced moisture fluctuations (Chapter 5). This was shown by a reduced recovery of bacterial nitrogen in plants compared to soils that were kept continuously moist.The effect of protozoan predation on the mineralization of carbon and nitrogen from soil organic matter was determined simultaneously in an experiment in which plants were grown in soil microcosms that contained 14C-carbon and 15N-nitrogen organic material both in the presence and absence of protozoa (Chapter 6). The predating activity of protozoa accelerated the turnover of microbial carbon and nitrogen by reducing the size of the bacterial population. But more important, protozoa stimulated the activity of the remaining bacterial population as judged from an ongoing higher rate of 14C-CO 2 respiration in the presence of protozoa compared to sails without protozoa. Protozoa responded immediately to the restoration of favourable moisture conditions in the soils as shown by the increased rate Of 14C-CO 2 respiration. These results support the observations that protozoa numbers increased within 1 or 2 days upon the addition of water to dry soils (Hunt et al. 1989). Furthermore, it was hypothesized that the flow of water contributed to a (re)distribution of protozoa. In soils that were inoculated with less protozoa, the rewetting response in terms of increased rate of 14C-CO 2 respiration, was larger than in soils inoculated with more protozoa.Several mechanisms for the action of protozoa with respect to mineralization of nitrogen have been proposed (Chapter l):1) by grazing bacteria, protozoan biomass is produced at the expense of bacterial biomass and excess nitrogen is excreted as ammonium2) by grazing bacteria, protozoa produce waste products (cell wall material and other nutrients) which in turn may enhance microbial activity3) whilst moving through the soil searching for food particles, protozoa might (re)inoculate (new) substrates by transporting bacteria that adhere to their cell surface or by bacteria that are not digestable and therefore excreted.In all experiments, the activity of protozoa reduced the size of the bacterial populations both in planted and in unplanted soils by a factor of two (Chapter 5 and 6), five (Chapter 3) to eight (Chapter 2). As a consequence, K is concluded that consumption of bacteria is responsible for at least a part of the increased mineralization of nitrogen in the presence of protozoa. Furthermore, the activity of protozoa induced an ongoing higher microbial respiration rate in planted soils (Chapter 6). It was demonstrated that a smaller sized bacterial population was more active in terms of the amount of carbon metabolized per unit microbial biomass when being predated upon by protozoa. Also, the presence of protozoa increased maintenance of the plasmid in a plasmid containing bacterial population.This was attributed to an improved nutrient availability in soils where protozoa grazed bacteria. With respect to the third mechanism through which protozoa could enhance mineralization of nitrogen, only limited information was available. It was shown that in unplanted soils (Chapter 3) that are incubated under stable soil moisture regimes, the migration and mobility of protozoa between aggregates is very much restricted (Vargas and Hattori 1986). Based on the observations on gene transfer, it could not be demonstrated that protozoa are important vectors in the allocation of bacteria through soil. However, it was hypothesized that water flow significantly contributes to the distribution of protozoa and probably bacteria as well through the soil matrix.That microorganisms are responsible for mineralization of nitrogen from organic sources in soils has long been recognized. The results, presented in this thesis, showed clearly that in soils protozoan grazing of bacteria substantially improves the availability of organically bound nitrogen to plants. The mechanisms by which protozoa stimulate the mineralization of nitrogen are i) by releasing nitrogen directly from bacterial cells and ii) by stimulating the turnover of soil organic matter through the microbial biomass. The microcosm approach proved to be useful to study the mineralization of nitrogen by protozoan activity in soil. The dynamic character of planted soil was demonstrated by an ongoing respiration of soil organic carbon. In fallow soil, the protozoan activity lasted only 10 days and then, gradually, microbial activity slowed down. However, in both planted and fallow soil, protozoa exhibited their stimulating effect on carbon and nitrogen mineralization rates. Without significant water flow through the soil matrix, the mobility and migration of protozoa is low. Reallocation of bacteria in the soil matrix was virtually absent. Hence, protozoa sec do not contribute to a (re)distribution and dispersion of bacteria through soil as hypothesized by Finlay and Fenchel (1989). Meanwhile, it was demonstrated that applying a combination of techniques from the field of microbial ecology and of genetics can substantially improve our understanding of the ecology of (introduced) soil microorganisms.Protozoa exhibited a very fast, immediate reaction to restoration of favourable moisture conditions in previously dried soils. The pulsed addition of water to dry soils have a significant impact on the dynamics of food-chain reactions in soil in terms of microbial activity and of carbon and nitrogen mineralization. Here, the effect of protozoa could be caused both by substrates made available to microorganisms through disruption of soil aggregates or through an improved distribution of the biota through the soil. The magnitude of the effect of protozoan grazing on the plant availability of organically and bacterial bound nitrogen supports the concept that food-web interactions rather than microbial activity alone, are responsible for nitrogen mineralization in soil.
AB - In general, more than 95% of the nitrogen in soils is present in organic forms. This nitrogen is not directly available to plants unless microbial decomposition takes place with the release of mineral nitrogen. In modern agriculture, nitrogen is often applied to arable soils as a fertilizer to support high levels of crop production. Nitrogen is one of the essential nutrients and is required by plants in substantial amounts (1.5-5% x g -1dry weight). Extensive application of fertilizer nitrogen causes substantial environmental problems such as leaching of nitrates into groundwater which is used as drinking water and ammonia volatilization into the atmosphere. This ammonia is deposited on the surface of the earth. Nitrification then results in acidification of soils and damage to plants.The microbial biomass in soil is both a source and a sink for nitrogen. This renders the turnover of nitrogen through the microbial biomass a key process in nitrogen cycling in soil. Knowledge about the mechanisms involved in the mineralization of nitrogen in soils is necessary to improve control of the nitrogen cycling in arable soils. Evidence is accumulating that interactions between microflora and fauna such as protozoa are responsible for a signicant portion of the mineralization of nitrogen in soils. In this thesis, the impact of protozoan predation of bacteria on the mineralization of nitrogen from bacterial cells in soil was investigated.Traditionally, the mineralization of nitrogen in soils has been attributed to the microflora, i.e. bacteria and fungi. Protozoa have long been recognized as the major predators of bacteria thereby regulating the size of the bacterial populations in soils. The potential impact of protozoa on the mineralization of nitrogen has only recently been recognized (Elliott et al. 1979). When protozoa consume bacteria, excess nitrogen is excreted as ammonium nitrogen. This relation is based on a similar carbon:nitrogen ratio for protozoa and bacteria. Additionally, it has been hypothesized that, by grazing bacteria, protozoa enhance microbial activity and eventually mineralize nitrogen from soil organic matter (Clarholm 1985).Experiments were carried out in microcosms containing sterilized soil that was inoculated with specific microbial populations. The turnover of the 15 N from microbial cells was assessed by growing plants on these soils and analysing the recovery of 15N in the plant. The activity of protozoa was inferred from an increased number of protozoa during the incubation period.In Chapter 2, the impact of protozoan grazing on the mineralization of nitrogen from bacterial biomass was investigated. Soil was inoculated with the basic composition of the food chain studied, i.e. 15N-labelled Pseudomonas aeruginosa alone or with protozoa. Protozoan grazing strongly stimulated the turnover and the mineralization of bacterial nitrogen. In the presence of protozoa, plants recovered 65% more bacterial 15N than in soils without protozoa. Furthermore, the presence of protozoa resulted in a 26% higher mineralization and uptake of nitrogen from soil organic sources. Additionally, a suspension with a natural bacterial population from the soil was added to the basic composition of the food chain. An increased number of bacteria would immobilize more nitrogen. It was hypothesized that consequently protozoan grazing would exert a more pronounced effect on the mineralization of nitrogen. In this case, the presence of protozoa stimulated the mineralization and uptake by plants of nitrogen from soil organic sources by 44% compared to soils without protozoa. However, the protozoan mediated mineralization and plant uptake of 15 N from bacterial cells was reduced by the addition of the bacterial suspension. This effect was explained by assuming that internal cycling of nitrogen occurred to a larger extent due to an increased size of the bacterial population when both a bacterial suspension and 15N-labelled Pseudomonas aerughosa were added.Soil provides a very heterogeneous environment with its network of pores with sizes from 0.2 μm to 2000μm. Microorganisms have been shown to be neither randomly nor uniformly distributed through the soil fabric (Foster 1988). Part of the habitable pore space for bacteria in soil is not accessible to protozoa (Vargas and Hattori 1986). The numbers of protozoa that are found in natural soil ranges from 1 x 10 4to 1 x 10 6per gram dry soil. Still, protozoa have to migrate through the soil matrix to meet their prey organisms. This is especially true under the experimental conditions in our microcosms where only up to 1 x 10 4protozoa per gram of dry soil have been inoculated at the start. The effect of the inoculum density of protozoa and of spatial separation of protozoa and (prey)organisms on the migration by protozoa as well as on the turnover, dynamics and transport of specific microbial populations in soil was studied (Chapter 3). The CO 2 evolution served as an indicator of microbial activity. The fate of introduced 14C-labelled bacterial cells was followed by monitoring 14C-CO 2 evolution. Two antibiotic resistant Pseudomonas fluorescens R2f strains were inoculated. The transfer of genes betweenrepresentatives of these strains via conjugation was a powerfull indicator of the distribution of bacteria and protozoa in soils. The activity of protozoa increased CO 2 evolution compared to soils not inoculated with protozoa. This stimulation of the CO 2 evolution was related to the percentage of a soil portion that was inoculated with protozoa. The inoculated number of protozoa did not affect the CO 2 evolution. This indicated that protozoa were only active in those particles into which they were inoculated. Protozoa accelerated the turnover of 14C . The more protozoa were inoculated, the faster specific 14C-labelled substrates were respired. The turnover of 14C was determined by the frequency of encounters between protozoa and labelled microorganisms. It was concluded that this frequency is a function of the concentration of protozoa and 14C-labelled microorganisms in the soil matrix. The results obtained in Chapter 3 picture the soil as a rather constrained system with respect to the mobility of both protozoa and bacteria in the soil matrix. Protozoa hardly influence the distribution of bacterial cells in soil through dispersion. Additionally, it was shown that protozoa did not affect the transfer of genes through organisms in soil. The results support the hypothesis by Stout (1973) that the activity of protozoa is confined to small spaces and consequently small populations.Protozoa are in essence aquatic organisms and therefore water is essential to their functioning. Based an the average cell sizes of 10-50 μm for amoebae and 10-20 μm for flagellates, these protozoa can only enter and feed in pores with a pore neck diameter 3- 20 μm and larger (Darbyshire 1976). The availability of water was shown to strongly regulate the grazing activity of protozoa (Chapter 5). In soils kept at a low soil moisture tension (3 Bar), protozoa were not active. It was estimated from a water retention curve (Postma et al. 1989) that at this moisture tension, pores with pore necks larger than 3 μm are devoid of water. Hence, protozoan movement and feeding was restricted because waterfilms were too thin or even absent. Only at higher soil moisture contents (0.1 Bar and 0.3 Bar), the activity of protozoa reduced the number of bacteria and increased the mineral nitrogen content in soil (Chapter 5).Upon drying of the soil, protozoa encyst to survive dry conditions. Little information is available on the signals and the time needed to excyst and return to trophic stages when favourable soil moisture conditions are restored. In a series of three experiments, plant water transpiration was used as an experimental tool to induce soil moisture regimes with defined fluctuations (Chapter 4 and 5). Even though protozoa were forced to encyst upon drying of the soil, they reacted very rapidly to remoistening. In soils that were incubated under conditions with modest soil moisture fluctuations, protozoan activity resulted in an even higher mineralization and plant uptake of 15N from bacterial cells than in soils that were incubated with a stable soil moisture regime. The activity of protozoa stimulated the mineralization of nitrogen from soil organic sources under all soil moisture regimes applied (Chapter 4). The protozoan activity was further restricted when soil moisture regimes were characterized by more intense and more frequently induced moisture fluctuations (Chapter 5). This was shown by a reduced recovery of bacterial nitrogen in plants compared to soils that were kept continuously moist.The effect of protozoan predation on the mineralization of carbon and nitrogen from soil organic matter was determined simultaneously in an experiment in which plants were grown in soil microcosms that contained 14C-carbon and 15N-nitrogen organic material both in the presence and absence of protozoa (Chapter 6). The predating activity of protozoa accelerated the turnover of microbial carbon and nitrogen by reducing the size of the bacterial population. But more important, protozoa stimulated the activity of the remaining bacterial population as judged from an ongoing higher rate of 14C-CO 2 respiration in the presence of protozoa compared to sails without protozoa. Protozoa responded immediately to the restoration of favourable moisture conditions in the soils as shown by the increased rate Of 14C-CO 2 respiration. These results support the observations that protozoa numbers increased within 1 or 2 days upon the addition of water to dry soils (Hunt et al. 1989). Furthermore, it was hypothesized that the flow of water contributed to a (re)distribution of protozoa. In soils that were inoculated with less protozoa, the rewetting response in terms of increased rate of 14C-CO 2 respiration, was larger than in soils inoculated with more protozoa.Several mechanisms for the action of protozoa with respect to mineralization of nitrogen have been proposed (Chapter l):1) by grazing bacteria, protozoan biomass is produced at the expense of bacterial biomass and excess nitrogen is excreted as ammonium2) by grazing bacteria, protozoa produce waste products (cell wall material and other nutrients) which in turn may enhance microbial activity3) whilst moving through the soil searching for food particles, protozoa might (re)inoculate (new) substrates by transporting bacteria that adhere to their cell surface or by bacteria that are not digestable and therefore excreted.In all experiments, the activity of protozoa reduced the size of the bacterial populations both in planted and in unplanted soils by a factor of two (Chapter 5 and 6), five (Chapter 3) to eight (Chapter 2). As a consequence, K is concluded that consumption of bacteria is responsible for at least a part of the increased mineralization of nitrogen in the presence of protozoa. Furthermore, the activity of protozoa induced an ongoing higher microbial respiration rate in planted soils (Chapter 6). It was demonstrated that a smaller sized bacterial population was more active in terms of the amount of carbon metabolized per unit microbial biomass when being predated upon by protozoa. Also, the presence of protozoa increased maintenance of the plasmid in a plasmid containing bacterial population.This was attributed to an improved nutrient availability in soils where protozoa grazed bacteria. With respect to the third mechanism through which protozoa could enhance mineralization of nitrogen, only limited information was available. It was shown that in unplanted soils (Chapter 3) that are incubated under stable soil moisture regimes, the migration and mobility of protozoa between aggregates is very much restricted (Vargas and Hattori 1986). Based on the observations on gene transfer, it could not be demonstrated that protozoa are important vectors in the allocation of bacteria through soil. However, it was hypothesized that water flow significantly contributes to the distribution of protozoa and probably bacteria as well through the soil matrix.That microorganisms are responsible for mineralization of nitrogen from organic sources in soils has long been recognized. The results, presented in this thesis, showed clearly that in soils protozoan grazing of bacteria substantially improves the availability of organically bound nitrogen to plants. The mechanisms by which protozoa stimulate the mineralization of nitrogen are i) by releasing nitrogen directly from bacterial cells and ii) by stimulating the turnover of soil organic matter through the microbial biomass. The microcosm approach proved to be useful to study the mineralization of nitrogen by protozoan activity in soil. The dynamic character of planted soil was demonstrated by an ongoing respiration of soil organic carbon. In fallow soil, the protozoan activity lasted only 10 days and then, gradually, microbial activity slowed down. However, in both planted and fallow soil, protozoa exhibited their stimulating effect on carbon and nitrogen mineralization rates. Without significant water flow through the soil matrix, the mobility and migration of protozoa is low. Reallocation of bacteria in the soil matrix was virtually absent. Hence, protozoa sec do not contribute to a (re)distribution and dispersion of bacteria through soil as hypothesized by Finlay and Fenchel (1989). Meanwhile, it was demonstrated that applying a combination of techniques from the field of microbial ecology and of genetics can substantially improve our understanding of the ecology of (introduced) soil microorganisms.Protozoa exhibited a very fast, immediate reaction to restoration of favourable moisture conditions in previously dried soils. The pulsed addition of water to dry soils have a significant impact on the dynamics of food-chain reactions in soil in terms of microbial activity and of carbon and nitrogen mineralization. Here, the effect of protozoa could be caused both by substrates made available to microorganisms through disruption of soil aggregates or through an improved distribution of the biota through the soil. The magnitude of the effect of protozoan grazing on the plant availability of organically and bacterial bound nitrogen supports the concept that food-web interactions rather than microbial activity alone, are responsible for nitrogen mineralization in soil.
KW - mineralisatie
KW - microbiële afbraak
KW - stikstof
KW - microbiologie
KW - mineralization
KW - microbial degradation
KW - nitrogen
KW - microbiology
M3 - external PhD, WU
PB - Kuikman
CY - S.l.
Kuikman P. Mineralization of nitrogen by protozoan activity in soil. S.l.: Kuikman, 1990. 103 p.


text:
Watch Video: "Our Awakening as PanDimensional Beings"
Our Awakening as PanDimensional Beings
$12.00 – Watch Video Checkout Added to cart
Speaker, scientist, researcher, Mr. Jack Stucki, will show you the unseen energies and other dimensions that do, indeed, affect us daily, and are the stuff that we are made of. He is able to photograph spirits and energies from beyond the veil using his "Bio-luminator" machine, which he developed after a decade of development. The bio-luminator device shows us that we are "pandimensional" beings and this is the adventure before us.
Mr. Stucki has discovered ways to prove there are unseen energies and other dimensions that do, indeed, affect us daily. From Jack's perspective, becoming "pandimensional" is the adventure before us. He has been able to photograph spirits and energies from beyond the veil using his "Bio-luminator" machine. With this he is able to alter the energy of the room, thereby creating an opening, or bleed-through from another dimension, that allows him to photograph otherwise unseen energies.
Mr. Stucki presents his work with slides of the luminator machine that he has developed over the last 25 years. Through the sensitivity of Polaroid photographs and the luminator machine, he gathered images of previous lives, spirit group members, and other entities that are around us. He will share these photos with us. This evidence can help us embrace the multi, or, pandimensional nature of our reality. Jack has had direct contact with benevolent beings for some time and will share some of the insights these beings have given him. From Jack's perspective, becoming "pandimensional" is the adventure before us.
Speaker, Mr. Jack Stucki, Inventor, Scientist, Researcher
Jack Stucki is a scientist and healer. Jack Stucki began his professional career in 1967 as a music therapist and evolved from there. His variety of energy research work has been featured on television talk shows and in books, including in three books published in 2010: Life Force, the Scientific Basis by Claude Swanson, Ph. D.; Radiant Minds edited by Jean Millay, Ph.D.; and Healing Stories by Robert Alcorn, M.D.
In 1991, he was a member of the fact-finding team studying the effects of the Chernobyl nuclear accident, and introduced professionals, in the Ukraine, to biofeedback. From 1995 through 2006 he was in private practice in Colorado Springs, CO, and continues to be involved in the Merkaba Research and Healing Center. He was the instructor for a course in Integrative Medicine for the University of Colorado Medical School.
Jack's main interest lies in using advanced technology to explore subtle energies. His work has been presented several times to The International Society for the Study of Subtle Energies and Energy Medicine (ISSSEM).
In June, 2011, Jack was awarded the prestigious Doug Boyd Wisdom Keeper Award during the annual conference of ISEEEM. This award is presented to selected individuals who exemplify the spirit of gathering and sharing ageless wisdom. Jack lives with his wife Judy in the mountains of Beulah, CO. Contact Mr. Stucki, for more information at stucki@socolo.net, 719-485-3789.
Our Awakening as PanDimensional Beings2018-10-082018-12-14https://www.paranormaltalks.com/wp-content/uploads/2018/09/logo-full-white-transparent.pngParanormal Talkshttps://www.paranormaltalks.com/wp-content/uploads/edd/2018/10/jackstuckivideo2017_11_12prt1-flat.jpg200px200px
Love is Our True Identity: A Soldiers Story
Beyond the Veil to Heaven: How Love Keeps Us Connected


text:
Resurgent women: The times they are a changin'
In this edited extract from his book 'Half a Billion Rising', Anirudha Dutta says, the coming decade will see more educated women entering the workforce and this will have far-reaching socio-economic implications. Men will have to respect and adapt to live with these changes.
Anirudha Dutta
Mar 08, 2016 12:03p.m.
[Edited extract from the introduction and chapter 9 of 'Half a Billion Rising' by Anirudha Dutta]
Girls and women in India have had eminent status and positions of power from ancient to modern times, in mythology and in real life. Consider this: the gods of learning, wealth and power are all women. Indian mythology is replete with references to princesses and queens who were not only the embodiment of beauty but also of valour, bravery, state craft and wisdom. During the independence movement and after independence we have had some very powerful and successful women political leaders like Sarojini Naidu, Vijay Lakshmi Pandit, and Indira Gandhi. Unlike most of their male counterparts, and irrespective of whether we agree with their politics or not, leaders like Jayalalithaa, Mayawati and Mamata Banerjee who have emerged over the last three decades are self-made. And it is not just in the field of politics. Take corporate India as well. In recent years many of the large financial institutions and banks, both in the private and public sector, have been led by women CEOs, a record that is globally unprecedented.
It would be easy to conclude that women in India enjoy an exalted status of respect and equality. But this is far from the truth. There has been a wide gulf in the power, esteem and respect that women deities in the Hindu pantheon and a few women in different walks of public life enjoy and what an average girl or woman has to endure through her life. …
But this cycle is changing and breaking down for good. We are at the cusp of a once in a lifetime change. What is increasingly evident is the rise of woman power in India as women get more educated, better informed, more empowered and traditional barriers collapse to give them near equal, if not equal, opportunities. Increasingly one sees and hears of women taking up formal corporate roles in managerial and technical positions as against traditional jobs like teachers and office assistants. The change has been long overdue.
This multi-decadal, once in a lifetime change I believe is an incredibly powerful trend with wide ranging implications over the next decade due to the sheer size of the opportunity. India is home to 586 million women, just over 17 per cent of the world's total number of women. India is also home to 173 million young women below the age of fifteen years, which is about 20 per cent of the world's young women's population. So the developments and changes in the lives of women, socially and economically, are of import not only to India but to the world at large.
LADKON KO KYA SIKHNA HAI—WHAT BOYS NEED TO LEARN AND THE IMPACT POINTS
As I transcribed the interviews and thought through my conversations, it was very evident that in the coming decade we will see greater participation of women in the labour force, we will see a more educated work force especially amongst women and these will have far reaching socio-economic implications like later marriages, lower fertility rates, better human development indicators and a greater degree of consumerism. Boys and men will have to respect the changes, accept the changes and adapt to live with the changes. It will be the new normal and will leave many maladjusted and bewildered.
During the course of my interviews through 2013, I often felt that the girls I met were more driven, more ambitious, more confident and generally doing better in most of the things that they were engaged in as compared to the boys in their community.
Throughout the interviews that I conducted across cities and across socio-economic strata, the message was very consistent. Girls have an urge to excel and are getting ahead. This is also reflected in the results of school board exams year after year when newspaper headlines scream how girls have performed better than boys. We have seen how more girls are graduating out of colleges than ever before and how they make up a third of the workforce in leading IT and financial services companies.
The impact of being more educated and smarter is already being felt when it comes to marriage. Indian parents are obsessed with the marriage of their children, girls and boys alike. With girls getting more educated and more ambitious, many of them will find it harder to find partners within their present socio-economic communities. Men will find it harder to handle a confident young woman who knows her mind and is unwilling to live by the earlier tenet of an adarsh bhartiya naari. In many of the stories that I have chronicled, I saw that girls were getting married to men who were less qualified. Give it another few years and many girls will not be willing to do so.
The challenges of finding a right partner will also cut across socio-economic strata. At one end is the mental conditioning, as we saw with Meghna and other girls, where they would like their husbands to be at least as qualified as they are, if not more. Saira told me that she would find it difficult to find a husband from her immediate community.
It is evident that the marriage age will rise, motherhood will be delayed, fertility will reduce and more women will start working in paid jobs outside their homes. Almost every girl I spoke to during this research said she would like to have two children, as against the fertility rate of 2.59 children per woman as per Census 2011, which itself is a decline of 18 per cent in a decade.
In 2007, CLSA, the investment bank that I worked in then, did two surveys among employees in the IT sector and financial services sector. The surveys found that among the respondents 54–57 per cent had spouses who were home makers and not engaged in full-time employment. However, among unmarried respondents, 84 per cent said that they would look for a working spouse and would prefer their spouse to be in full-time employment. What was particularly interesting was that preference for a working spouse remained unchanged between respondents from the top seven cities versus the other 240+ cities.
The picture that emerged from the surveys is very clear. In this decade and over the next, women's participation in the labour force will rise, both in urban and semi-urban areas. This will drive two trends. The first one is that men will have to share more household chores. Traditionally the world over, women do the lion's share of work in their homes. Even today in developed societies like the US, working women do the major share of the work in their homes. As Sheryl Sandberg wrote in Lean In, 'I still struggle with the trade-offs between work and home on a daily basis. Every woman I know does…' And Indra Nooyi, PepsiCo CEO, recently said that women can't have it all which sparked a lively debate in the media.
The west is much better at it than India where boys in a majority of the households are still brought up thinking that they are special and do not need to do any household chores, which is the primary job of girls and women. Families will need to ensure that boys participate in household chores as much as the girls do. Interview after interview, the girls said that they expect their partners and husbands to share in household chores. Training for this will have to start not during dating or after marriage, but much before that. This is what Tina meant when she told me that Indian mothers will need to teach their sons how to change nappies.
Changes at the societal level are not just about finding equal and supportive partners but they also need to drive attitudinal and behavioural changes among men and in society at large towards girls and women. It has been seen that childhood experiences of abuse and violence are associated with the perpetration of violence in most countries. Therefore, change has to start early and will have to happen at the family and local community levels. Once again the role of governments and more importantly grassroot NGOs will be critical.
Another trend will be of the increasing number of househusbands or husbands in temporary or part-time jobs as their wives have high flying careers. Already in metros it is easy to see fathers dropping their children to school or attending parent teacher meetings because their wives are travelling on work. There is nothing non-masculine about it. Men the world over are doing it although the change is very slow.
Shreya Sen Handley, a prolific blogger and contributor to different newspapers and magazines across the world including National Geographic, recently wrote:
And it's still frowned upon for men to become stay-at-home dads. Between 1993 and 2007, the number of stay-at-home dads had gone up by a huge 83 per cent in the UK. By 2007, in the US, homemaking dads made up approximately 2.7 per cent of the nation's stay-at-home parents, triple the percentage from 1997, and up every year since 2005. In India, according to a 2006 study, as much as three percent of all urban fathers were stay-at-home dads, which would have been unacceptable and unheard of a decade before that. And yet, in every case, it is a very small percentage of the male population, because this is a 'role reversal' that frightens most men and many women.
Sheryl Sandberg in Lean In says that of her batch of MBAs from Harvard, nearly 50 per cent of the women had dropped out of the workforce in twenty years. She writes:
But more than twenty years after my college graduation, the world has not evolved as much as I believed it would. Almost all my male class mates work in professional settings. Some of my female classmates work full-time or part-time outside the home, and just as many are stay-at-home mothers and volunteers like my mom. This mirrors the national trend.
A 2007 survey of Harvard Business School alumni found that in less than ten years after graduation only 81 per cent of the women who graduated continued to work full-time and in fifteen to twenty years the number declined to 49 per cent.
This is important to mention since girls who were pursuing MBA in Harvard had presumably decided to have a career and must have been among the brightest and most ambitious within their cohort. In USA, 74 per cent of professional women who drop out of the workforce return to work in any capacity and only 40 per cent return to full-time jobs, as they change their focus to having a family and then on supporting their husbands and their children. In India the problem is also acute since the participation of women in the labour force is low to begin with and then a large number of women drop out from the workforce to bring up their families.
Women make up only 24 per cent of India's workforce and only 5 per cent of them reach the top as compared to the global average of 20 per cent. A recent study found that 36 per cent of Indian working women take a break; this proportion is similar to USA and Germany. Interestingly they take shorter breaks at an average of 11 months as against 2.7 years in the US and 1.9 years in Germany, with 58 per cent returning to full time jobs. What is different is that in India women take breaks for childcare and also for elder care; but while childcare is slowly being outsourced, elder care still is not. According to Infosys, while competitive career opportunities is the top reason for men who leave, for women it is personal reasons and attrition among women is higher than it is among men.
Experiences of companies like ICICI Bank show that women are not only as productive as their male counterparts but are also excellent leaders. To realize their potential, corporate policies will have to be designed to support and keep women in the workforce for longer. Some of the obvious measures are flexible working hours, longer maternity leave, generous childcare support, paternity leave, quality childcare services and support close to place of work or larger housing complexes in cities like Mumbai and Bengaluru. If the intent is right, more creative solutions will emerge.
As more girls start working, the marriage age will be pushed upwards and coupled with the trend that more girls by choice or otherwise will possibly remain single, we are likely to see lower fertility rates, more adoption of children and better child and maternal health. Within my circle of friends I know of at least two couples who have decided not to have biological children and have opted for adoption in the last decade. One of the prominent role models that has emerged is Sushmita Sen, model, actor and former Miss Universe, who as a single parent has adopted two daughters. There are many more couples I know who have decided not to have any children so as not to compromise with their careers or their lifestyles.
Later marriages and better education will mean better maternal and child health. Coupled with slightly better governance in the public space this will mean dramatic improvements in social and human development indicators.
According to data from the National Sample Survey's (NSS) sixty-eighth survey, the labour force participation rate (LFPR) in the age group of 15–59 years for the entire population was 58.3 per cent. The numbers for men and women were 83 per cent and 33 per cent respectively. Even today nearly 70 per cent of women not in the labour force are engaged in domestic duties and a lesser percentage are in education and/or retired. The numbers for rural and urban India are starker.
While LFPR for men in urban and rural areas was 81 per cent and 84 per cent respectively, the numbers for women were 22 per cent and 38 per cent respectively. This is another paradox. Given more opportunities in urban India and better qualifications (higher education and better skill set development opportunities), one would naturally have expected that the labour force participation rate would be higher in urban India than in rural India. But that is not the case. This is possibly due to the fact that in rural India a larger proportion of women engage in manual labour in the fields or in construction, whereas in urban India, led by higher economic standards, women have access to office or domestic jobs, which are smaller in number; many may choose not to enter the job market.
[One] reason is that as women get more educated, as is evident from school enrolments and their proportion in colleges and universities, their entry into the workforce is delayed and thus, it will not be surprising to see the labour pool shrink in certain age groups even as the overall quality of the labour pool improves significantly.
To improve women's participation in the labour force more jobs will have to be generated closer to home, there has to be a quantum leap in day care facilities for children close to home and close to places of work and increased opportunities for women to work from home and with flexible working hours, if necessary. These are issues that policy makers need to think about as we prepare for a period when women's participation in the workforce is bound to increase. I remember listening to Professor Nirmalya Kumar many years back speaking about Zara's manufacturing model in Italy. Zara had organized local women's co-operatives in different localities in what was a win-win situation. It meant that Zara could still keep a part of its production in a country like Italy when most garment manufacturing was moving to China and other emerging countries without losing its cost competitiveness due to tax and other benefits, and for the women it meant working in small groups close to home.
In India there are small entrepreneurs, NGOs and some companies like Fabindia which follow the same model but this has to be scaled up to make a difference as millions of women are employed in this way. Flipkart, India's largest online retailer and market place, is planning to link traditional craftsmen and artisans to customers through its platform.
This tectonic shift of better educated, more aspirational girls and their increase in the workforce will present huge opportunities for a wide range of companies and service providers. A report titled 'XX Factor: The Impact of Working Women on India's Growth, Incomes and Consumption' published in 2007 estimated that increased women's participation in the workforce, XX trend, could make Indians 12 per cent richer by 2025 than otherwise projected. When the report was published, the author had estimated that the XX trend 'could add US$35bn to GDP, lifting incremental demand by 10 per cent'.
This coupled with the fact that the coming generation will be relatively more resource rich and time constrained will provide an opportunity for suppliers of different products and services. Once women start working and gain some amount of independence and control over their economic well-being and finances, they will have a larger say in the savings and consumption of households. Across a range of household expenditures, working women spend more than non-working women given that they have more control over their finances and better say in how they spend and what they earn.
Multiple sectors will be big beneficiaries. Given that women focus more on the education and healthcare of their families, clearly education and out of school classes will be the first beneficiaries. Retail financial services will find a new cohort of consumers and they will need to tailor-make their products in some cases to address this group of consumers as it becomes significant in numbers.
Products and services that can help save time or free up time for leisure and quality family time will be lapped up.
Companies and businesses that identify and cater to these trends will be big beneficiaries and long term winners.
This excerpt from Half a Billion Rising by Anirudha Dutta is reprinted with the permission of Rupa Publications India.
Buy it on Amazon
Buy it on Flipkart
Was this article useful? Sign up for our daily newsletter below
Half a Billion Rising
Analyst, Financial services sector
Anirudha Dutta has been working in the financial services sector for over two decades. He holds a degree in engineering from IIT, Kharagpur, and a postgraduate diploma in business management from XLRI, Jamshedpur. 'Half a Billion Rising: The Emergence of the Indian Woman' is his first book.
Also by me
For women within the modern home, a glimpse into a more equitable future
Technology, nostalgia and the rise of radical nationalism
The IPO boom in internet stocks: How to separate the good from the bad
Top Ten books of 2021
Dealing with the digital tsunami
The ridiculous "Principles" of Ray Dalio
The McKinsey case and consulting's ethical dilemma
The Rahul Yadav Story You've Never Heard Before
Saving Private Flipkart
The fault in our startups
Flippin' over backwards
A day in the life of India


NOTE: Priority will be given to participants originating from Europe and North African countries. UNESCO is committed to promote gender equality. Therefore, applications from women are strongly encouraged.