Brown tide algal blooms, caused by the excessive growth of Aureococcus anophagefferens, recur in several northeastern US coastal bays. Direct bloom control could alleviate the ecological and economic damage associated with bloom outbreak. This paper explored the effectiveness and safety of natural chemical biocide hydrogen peroxide (H2O2) for brown tide bloom control. Culture studies showed that H2O2 at 1.6 mg L−1 effectively eradicated high density A. anophagefferens within 24-hr, but caused no significant growth inhibition in the diatoms, prymnesiophytes, green algae and dinoflagellates of >2–3 μm cell sizes among 12 phytoplankton species tested over 1-week observation. When applied to brown tide bloom prone natural seawater in a microcosm study, this treatment effectively removed the developing brown tide bloom, while the rest of phytoplankton assemblage (quantified via HPLC based marker pigment analyses), particularly the diatoms and green algae, experienced only transient suppression then recovered with total chlorophyll a exceeding that in the controls within 72-hr; cyanobacteria was not eradicated but was still reduced about 50% at 72-hr, as compared to the controls. The action of H2O2 against phytoplankton as a function of cell size and cell wall structure, and a realistic scenario of H2O2 application were discussed.
Copyright: © Randhawa et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: The authors have no funding or support to report.
Harmful algal bloom (HAB) is a growing global problem, and in recent decades it has been seen increasing not only in the bloom incidences, but also in harmful species, affected areas, impacted fisheries resources and economic losses , , . Direct bloom control refers to actions taken to suppress or destroy HABs – to directly intervene the bloom process , . Among the physical, chemical and biological methods, only clay flocculation/sedimentation is well explored with reported field application successes in some Asian countries , . Chemical methods have not been actively explored for algal bloom control, partly because of concerns on environmentally acceptability of the chemicals, and the potential side effects on other organisms , , . The goal of this study is to explore the capability of one of the natural chemical biocide, hydrogen peroxide (H2O2), to effectively yet safely control brown tide algal blooms.
The brown tide algal blooms in northeastern US coastal bays are caused by the excessive growth of Pelagophyte Aureococcus anophagefferens, a species of unknown existence prior to the massive outbreak in 1985 . The organism is named after its golden brown color, minute spherical cell shape (about 2 μm diameter), and toxin release that causes feeding cessation of a number of filter feeders . During the bloom high cell density (e.g. 106 cell mL−1) of A. anophagefferens discolors the water, causes severe light attenuation and subsequent decline of the submerged aquatic vegetations (SAV). The toxin(s) secretion, thought to be associated with A. anophagefferens exopolymer on cell surface, affects shellfish and zooplankton feeding behavior , . The decline of SAV, which serves as the habitat and nursery ground for juvenile shellfishes, together with the feeding cessation response in juvenile shellfish species had devastated the commercial shellfishery in the affected area, such as the hard clams in New Jersey, bay scallop in New York, blue mussels in Rhode Island , . Fortunately, in some of the brown tides recurring bays, the brown tides were localized with the possible initiation sites identifiable, for example, the Peconic Sound and Shennecock Bay for East Long Island brown tides , and Manahawkin Bay for Barnegat Bay brown tides . This makes direct brown tide bloom control possible .
Hydrogen peroxide (H2O2) is naturally produced in sunlit surface seawater from photochemical reaction of dissolved organic matter, oxygen and trace metals , . Reported quantum yield ranged from 4200 to 2.1 μmol H2O2 mol−1 photons at <340 nm light , and in mid-summer day H2O2 was reported to potentially accumulate at 30–59 nM hr−1 for several hours in 0.2 μm filtered seawater in Narragansett Bay, Rhode Island . In coastal marine recreational water of Southern California summer dry season H2O2 concentrations averaged 122±38 nM . Steigenberger  reported surface H2O2 ranged from 21 to 123 nM along a meridional transect in the eastern Atlantic Ocean. Rain water also contains hydrogen peroxide; up to 57 µM, approximately 2 mg L−1, were observed in wet deposition in Bermuda Atlantic Time Series Stations . On the other hand, hydrogen peroxide is rapidly decomposed into water and oxygen, via enzyme reactions mediated by microorganisms, trace metal catalysis, halide, organic carbon, and direct photochemical loss , , , .
Hydrogen peroxide has been commonly used in industry, agriculture, aquaculture and environmental and personal hygiene applications for its oxidizing and microbiocidal properties. In environmental field it has been used in drinking water and wastewater treatment , , , (including cyanobacterial toxin removal , , ) in situ chemical remediation and to enhance in situ bioremediation of contaminated water, soil and sediment . In aquatic environment, it has been approved for freshwater aquaculture usage as an antifungal and antibacterial therapeutic agent for the prevention and control of mortalities associated with external fungal infections (saprolegniasis) in cultured fish and fish eggs , . H2O2-based products, such as sodium percarbonate, has been used as aquatic herbicides and microbiocide to manage algae, cyanobacteria, fungi and microorganisms in water (e.g. Massachusetts  and New York State ). Cyanobacteria were found more sensitive to H2O2 than eukaryotic phytoplankton , . Low dose hydrogen peroxide has been shown successful in controlling a cyanobacteria bloom and microcystin toxin caused by Planktothrix agardhii . In the study of Matthhijs et al. a special dispersal device (water harrow) was used to disperse H2O2 to the lake at 2 mg L−1, it resulted in more than 99% reduction of bloom organism of Planktothrix agardhii and algal toxin microcystin within a few days, while the eukaryotic phytoplankton, zooplankton, and macrofauna remained largely unaffected .
This study was carried out to examine the effectiveness of hydrogen peroxide in brown tide bloom control, and the safety of its application for the other and possibly co-occurring phytoplankton species. We first established a dose that effectively removed laboratory cultures of brown tide alga A. anophagefferens; then compared the H2O2 susceptibility of A. anophagefferens with eleven other marine phytoplankton species. Next, the response of the natural phytoplankton community to H2O2 exposure was examined by analyzing photosynthetic pigments of the algal community using high performance liquid chromatography (HPLC). The results provided an initial assessment on the effectiveness and safety of hydrogen peroxide in brown tide bloom control.
Phytoplankton species investigated in this study were obtained from Provasoli-Guillard National Centre for Marine Phytoplankton (CCMP; now NCMA) and included the brown tide bloom alga Aureococcus anophagefferens (Aa), five diatoms Phaeodactylum tricornutum (Pt), Minutocellus polymorphus (Mpo), Thalassiosira pseudonana (Tp), Skeletonema costatum (Sc), and Thalassiosira weissflogii (Tw), two green algae Micromonas pusilla (Mp) and Dunaliella tertiolecta (Dt), two dinoflagellates Amphidinium carterae (Ac) and Prorocentrum micans (Pm), and two Prymnesiophytes Isochrysis galbana and Emiliania huxleyi (Table 1). These species are common in marine waters, among them green algae Mp were found in abundance in non-bloom and postbloom waters , , and the diatoms Pt and Tp were found to co-exist with brown tide bloom in Quantuck Bay, NY , Mpo, Tp, Sc and Pm were also found in pre-bloom or post-bloom waters , . These species were maintained in artificial seawater Aquil or Aquil-Si (Aquil without silicate addition, for species other than diatoms), which were prepared and sterilized according to Price et al . Polycarbonate bottles (Nalgene, cleaned with detergent and acid) were used as culture vessels. All cultures were incubated in a diurnal growth chamber with 120 µE m−2 s−1 illumination from cool white fluorescence bulbs at 12∶12-h light-dark cycle, and 19±1°C.
Table 1. Marine phytoplankton species used in the study, listed group-wise and in order of increasing size.
Hydrogen peroxide (Fluka-95321, TraceSELECT®, 30% w:w, 9.8 M, kept in refrigerator and in dark) was first diluted with sterile culture medium to 10 mM (∼0.03%), then immediately added to the mid- or late-exponential phase cultures. Upon gentle mixing, the cultures (50 mL in 250 mL Nalgene polycarbonate bottles) were returned to the growth chamber for incubation. The nominal H2O2 addition was 0, 0.8, 1.6, 3.2 and 6.4 mg L−1 for A. anophagefferens, and 0, 1.6 and 6.4 mg L−1 for other algal species. The nominal concentrations of hydrogen peroxide were confirmed with 10–15% accuracy using spectrophotometric method of Lu et al. , where H2O2 reacted with p-nitrophenylboronic acid stoichiometrically at pH 9 producing p-nitrophenol of 19400 cm−1 M−1 absorptivity. Cultures without H2O2 addition were used as controls. Cultures were in triplicates for A. anophagefferens, and duplicates for other species.
Parameters reflecting algal growth were monitored, typically at 0 hr (immediately before adding H2O2), 3 hr, and then daily up to 1 week after H2O2 addition. The in vivo fluorescence (IVF) was monitored using Turner Designs' Trilogy Fluorometer (equipped with an optical block for in vivo chlorophyll a measurement, excitation 485 nm, emission 685 nm, band width 50 nm). Cell density was measured by Coulter Counter Multisizer 3 (equipped with a 70 μm aperture tube, Beckman). Total chlorophyll a (chl a) was measured with GF/F filtration, 90% acetone extraction, and UV-Vis spectrophotometer (Agilent 8453) quantification using Jeffery and Humphrey's trichromatic equation following EPA method 446.0.
Throughout the study Minitab 16 Software Package was used in statistical analysis with probability p<0.05 being accepted as statistically significant. Two-sample t-tests were used to compare the control cultures and the H2O2 treated cultures. Paired t-tests and/or ANOVA (analysis of variance) were used to compare temporal variation of the cultures. Exponential growth or log-linearity was determined with regression analysis. Regression was also used to determine the correlation between percent inhibition and both cell size and H2O2 dose.
Natural seawater was collected from Barnegat Bay, NJ, which is prone to summer brown tide, by pumping surface seawater into 20-L carboy (pre-cleaned with detergent and acid) from a boat on July 28, 2010. (No specific permission is required to collect seawater from Barnegat Bay, NJ, as it is not privately-owned nor protected in any way. The work does not involve endangered or protected species.) Collected seawater was kept in a cooler and stored in cold-room (4°C) for processing next day. The upper Barnegat Bay summer phytoplankton assemblage typically consists of small coccoidal picophytoplankton complex (<5 μm) Aureococcus-Chlorella-Nannochloris-Synechococcus complex, other small flagellates of 3–7 μm size (chrysophyte e.g. Calycomonas oval, prasionophyte e.g. Micromonas sp.), prymnesiophytes such as Chrysochromulia sp., diatoms of small or large sizes (e.g. Minutocella polymorphus, Thalasiosira sp., Cyclotella sp), and small numbers of larger species (>15 μm) e.g. eugalenophyte Eugalena sp, and raphidophyte Heterosigma carterae .
In order to test cell size dependency, if any, of H2O2 action, a fraction of the collected natural seawater was passed through 5 µm PTFE membrane filters (Millipore) under low vacuum pressure (<5 psi). Unfiltered and 5 µm filtered seawater microcosms were set up by distributing 450 mL seawater into 500 mL sterilized polycarbonate bottles, and subsequently inoculating 35,000 cell mL−1 cultured A. anophagefferens (to mimic a medium density brown tide bloom) . H2O2, freshly prepared in sterile Aquil at 10 mM, was added at 1.6 and 6.4 mg L−1. The controls (microcosms without H2O2 addition) and 1.6 mg L−1 H2O2 treatments were in triplicates; microcosms with 6.4 mg L−1 H2O2 addition were not replicated. The microcosms were incubated in the growth chamber as in the culture study.
Total phytoplankton growth, A. anophagefferens cell density, and phytoplankton community composition were analyzed at 0 hr (immediately before H2O2 addition), and then daily up to 72 hrs of H2O2 addition. Total phytoplankton growth was analyzed via in vivo chlorophyll fluorescence and total chl a (same as in culture study). Changes in phytoplankton community composition were tracked via accessory pigment analysis: 19′-butanoyloxyfucoxanthin (19′-bf) for brown tide alga A. anophagefferens , fucoxanthin for diatoms and other chrysophytes, chlorophyll b (chl b) for chlorophytes and prasinophytes, peridinin for dinoflagellates, and zeaxanthin for cyanobacteria, respectively , . A. anophagefferens cell density was further estimated from a standard curve that correlated the number of cultured A. anophagefferens cells used in the pigment analysis and the resulting chromatographic peak area of 19′-bf.
Accessory pigment analysis followed Van Heukelem and Thomas' HPLC method . Briefly, 75 mL microcosm water sample was filtered through GF/F (nominal pore size 0.7 μm, 25 mm, Whatman, vacuum pressure <5 psi), and the filters were immediately preserved in liquid nitrogen. During analysis, the filters were put in 2-mL 90% acetone in amber micro-centrifuge tubes (VWR 20170–084) and sonicated in ice-cold water bath for 30 minutes (Ultrasonic FS-28, Fischer Scientific) to extract the pigments. The acetone extracts were centrifuged and the supernatants filtered through 0.45 µm PTFE syringe filters (4 mm, Pall Life Sciences) for HPLC analysis. These operations were in dim lights to minimize photo-degradation of the pigments. A Waters HPLC system, equipped with Waters 2690 separation module, refrigerated auto sampler, Eclipse XDB C8 column (150 x 4.6 mm, 3.5 µm, Agilent) and guard column, column heater, Waters 486 UV-VIS absorbance detector set at 450 nm, and SRI Model 333 USB Chromatography Data System, was used in pigment analysis following Van Heukelem and Thomas . Pigments were identified by comparing the retention times of the standards, including chlorophylls a, b, β-carotene (Sigma Aldrich), and fucoxanthin (DHI Group, Denmark). Other pigments were identified by comparison with the culture extracts from A. anophagefferens, Amphidinium carterae, Synechococcus sp. and Dunaliella tertiolecta for 19′-bf, peridinin, zeaxanthin and chl b respectively.
Hydrogen peroxide at 1.6 mg L−1 effectively inhibited A. anophagefferens growth as was observed with in vivo chlorophyll a fluorescence, total chl a, and cell density (Fig. 1). The inhibition was transient at 0.8 mg L−1 but was lasting at ≥1.6 mg L−1 H2O2 (Fig. 1). The starting cultures were in the late exponential growth phase, with in vivo fluorescence averaged 2565±35 (relative fluorescence unit, 15 cultures), total chl a 41.5±1.2 μg L−1, and cell density 1.98±0.4 million cells mL−1. The control cultures experienced 4.5-fold log-linear increase in in vivo fluorescence during 1-week incubation (Ln F = 7.87+0.20 t, where F is the in vivo fluorescence, t is time in days, R2 = 0.989, p = 0.000), but the cultures with 0.8 mg L−1 H2O2 addition had a decrease in in vivo fluorescence nearly 50% at 24-hr (p = 0.001) which then rebounded at a rate comparable to that of the control cultures (p = 0.975). More importantly, the cultures with 1.6, 3.2 and 6.4 mg L−1 H2O2 addition showed 98%, 99.7% and 99.7% (p = 0.000) decrease in in vivo fluorescence at 24-hr and re-growth was not observed over 1 week (Fig. 1A). Total chl a in these cultures (with 1.6, 3.2 and 6.4 mg L−1 H2O2) decreased more than 90% (p≤0.002) at 24-hr, and were below detection limit at 1-week (Fig. 1B). In the cultures with 1.6 mg L−1 H2O2 addition, cell density decreased log-linearly (LOG cell/L = 9.06–0.138 t, where t is time in days, p = 0.000) from nearly 2 to 0.5, 0.34 and 0.16 million cells mL−1at 24-hr, 48-hr and 1-week respectively; and in the cultures with 3.2 and 6.4 mg L−1 H2O2 addition, it decreased >90% to below 0.19±0.02 million cells mL−1at and after 24-hr (Fig. 1C).
Figure 1. Culture study Aureococcus anophagefferens growth response.
Response of Aureococcus anophagefferens cultures to the H2O2 addition at 0 (control, ◊), 0.8 (□), 1.6 (Δ), 3.2 (x) and 6.4 (*) mg L−1. A) In vivo chlorophyll a fluorescence. B) Total chl a. C) Cell density. Vertical error bars represent standard deviations of triplicate cultures.
Medium effective concentration, EC50, was calculated from in vivo fluorescence based on the logistic model where R is growth response (% inhibition on in vivo fluorescence relative to the controls), K is the growth response of the control (K = 1), C is H2O2 concentration (mg L−1), EC50 is medium effective concentration. The resulting EC50s for A. anophagefferens were 1.39±0.06 mg L−1 at 3-hr, and 0.91±0.00 mg L−1 at 24-hr and remained at this level during 48-hr –1-week.
Overall, A. anophagefferens growth response suggested that H2O2 at 1.6 mg L−1 or higher concentrations effectively removed high density A. anophagefferens within 24-hr exposure (>90% in total chl a), and re-growth was not observable during 1-week incubation.
Because effective (>90% in total chl a) A. anophagefferens removal was accomplished by 1.6 mg L−1 H2O2 treatment, comparisons on the survival and re-growth of A. anophagefferens with 11 other marine phytoplankton species (5 diatoms Pt, Mpo, Tp, Sc, Tw; 2 green algae Mp and Dt, 2 prymnesiophytes Ig and Eh, and 2 dinoflagellates Ac and Pm) were carried out, by exposing the growing or grown cultures of similar in vivo chlorophyll fluorescence (thus similar initial biomass) to 1.6 mg L−1 H2O2.
Among these 11 phytoplankton species only Micromonas pusilla (Mp) (a very small green algae, Class of Prasinophyceae, Phylum of Chlorophyta) was eradicated by 1.6 mg L−1 H2O2 (Fig. 2). The in vivo fluorescence of Mp decreased >90% within 24-hr of 1.6 mg L−1 H2O2 addition, and remained low during the 1-week observation, similar to A. anophagefferens tested in parallel (Fig. 2A). A toxic dinoflagellate, A. carterae (Ac), had an overall 17% lower growth rate as compared to its control cultures (p = 0.018, Fig. 2E).
Figure 2. Response of various phytoplankton species in culture study.
Variation of in vivo fluorescence of 12 marine phytoplankton species upon H2O2 addition at 0 (control, solid line) and 1.6 mg L−1 (treatment, dashed line). A) Aureococcus anophagefferens (Aa) and prasinophyte Micromonas pusilla (Mp). B) Diatoms Phaeodactylum tricornutum (Pt), Minutocellus polymorphus (Mpo), Skeletonema costatum (Sc), Thalassiosira pseudonana (Tp) and Thalassiosira weissflogii (Tw). C) Chlorophyte Dunaliella tertiolecta (Dt). D) Prymnesiophytes Isochrysis galbana (Ig) and Emiliania huxleyi (Eh). E) Dinoflagellates Amphidinium carterae (Ac) and Prorocentrum micans (Pm). Vertical error bars are deviations between duplicate cultures.
The growth of the rest 9 species, i.e. the diatoms Pt, Mpo, Tp, Sc, Tw (Fig. 2B), the other green algae Dt (Fig. 2C), the prymnesiophytes Ig & Eh (Fig. 2D), and the dinoflagellate Pm (Fig. 2E), were not affected by 1.6 mg L−1 H2O2 addition, as compared to the respective controls (p>0.05, two-sample t-tests on growth rates for Pt, Ig, Dt and Pm, which grew exponentially both with and without H2O2 addition, and two-sample t-tests on in vivo fluorescence at each time point for Mpo, Tp, Sc, Tw, Eh which did not grow exponentially during the 1-week observation. The exponential growth status was determined with log-linearity regression analysis with r ≥0.88, n = 4, p<0.05.).
Exposure of these species to H2O2 at 6.4 mg L−1 revealed cell size dependent species sensitivity (Table 2). It was found that the smaller the cell size the more sensitive it is to H2O2. For example, among the diatoms, with decreasing cell size (Tw >Sc >Tp >Mpo >Pt) the percent inhibition increased from non-inhibitive in Sc and Tw to more than 90% inhibition in Pt (Table 2). An empirical correlation was found statistically significant: % inhibition = 0.688–0.0561 x cell diameter +0.00262 x H2O2/chl a (p = 0.005, n = 12, R2 = 0.69) where % inhibition is the average % inhibition at 24-hr, 48-hr and 72-hr upon 6.4 mg L−1 H2O2 addition as compared to the control, cell diameter is the mean cell size measured by Coulter counter (μm), and H2O2/chl a is the weight ratio, mg H2O2/mg chl a, at time zero. Since dinoflagellate Pm (45 μm) is substantially larger than the rest of the species (1.4–11.05 μm), a correlation of 11 species excluding Pm was also established, % inhibition = 0.913–0.0952 x cell diameter +0.00224 x H2O2/chl a (p = 0.006, n = 11, R2 = 0.72), to reflect species sensitivity as a function of cell size and H2O2 dose. In this regression, the cell diameter alone was found to explain 40% of the variations.
Table 2. Mean cell diameter as measured by Coulter counter, and percent growth inhibition (mean ± standard deviation) at 24-hr, 48-hr and 72 hr after addition of 6.4 mg L−1 H2O2, as compared to the controls, of the 12 phytoplankton species tested.
A. anophagefferens cell density was estimated at 27,900±5,379 cell mL−1 (n = 2) in the original Barnegat Bay water samples, and at 54,150±3,188 cell mL−1 in the testing microcosms before H2O2 addition (n = 12, laboratory cultured A. anophagefferens was added to the microcosms). In the control microcosms (i.e. no H2O2 addition), A. anophagefferens cell density increased 60% at 24-hr as compared to time zero (p<0.05), and remained nearly constant at 24-hr, 48-hr and 72-hr (p>0.05, one way ANOVA, for both unfiltered and 5-μm filtered seawater microcosms), suggesting a developing brown tide bloom (Fig. 3A). In microcosms with 1.6 mg L−1 H2O2 addition, A. anophagefferens was eradicated (∼100%) at 24-hr, and its cell density remained low during the entire 72-hr study period, in both unfiltered and 5-μm filtered seawater microcosms (Fig. 3A).
Figure 3. Aureococcus anophagefferens response in microcosm study.
Variation in cell density of Aureococcus anophagefferens (A), in vivo chlorophyll fluorescence (B), and total chlorophyll a (C) in microcosms with 1.6 mg L−1 of H2O2 addition (treatment, dashed line) and without H2O2 addition (control, solid line). The microcosms were made of unfiltered (square symbols) and 5 μm filtered (triangle symbols) Barnegat Bay seawater amended with laboratory A. anophagefferens cultures. Vertical error bars represent standard deviations of triplicate microcosms.
While A. anophagefferens was eradicated in the phytoplankton assemblage, total phytoplankton productivity remained robust after a transient suppression at 24-hr and 48-hr (Fig. 3B). Specifically, after 1.6 mg L−1 H2O2 addition, the in vivo fluorescence was 50–60% lower than the controls at 24-hr and 48-hr (p≤0.001), but recovered, at 72-hr, to a level comparable to (p = 0.333, the 5 μm filtered microcosms,) or even higher (p = 0.035, the unfiltered microcosms) than those in the control microcosms (Fig. 3B). The transient initial suppression and subsequent recovery was also evident from total chl a. Total chl a was reduced 40–55% at 24-hr and 48-hr, as compared to the control, but recovered to exceed the control by 40% and 70% in 5 μm filtered and unfiltered microcosms, respectively (p<0.01) (Fig. 3C).
The response of the rest of the phytoplankton assemblage to 1.6 mg L−1 H2O2 treatment was estimated from algal marker pigments, fucoxanthin for diatoms and other chrysophytes, chl b for green algae, peridinin for dinoflagellates and zeaxanthin for cyanobacteria (Table 3). In the unfiltered seawater microcosms, fucoxanthin was reduced (by 1.6 mg L−1 H2O2) by 55% at 24-hr (p = 0.006) and 44% at 48-hr (p = 0.000), but subsequently recovered and exceeded the controls by 104% at 72-hr (p = 0.003); chl b was reduced approximately 55% at 24-hr and 48-hr (p<0.01) then recovered to a level not significantly different from the controls (p = 0.267) (Table 3). In the 5 μm filtered seawater microcosms, fucoxanthin was reduced about 58% at 24-and 48-hr (p<0.01) then exceeded the controls by 66% at 72-hr (p = 0.000); chl b was exceeded by the control by 54–67% at 24-hr and 48-hr (p<0.01) and then to a less degree of 17% at 72-hr (p = 0.018) (Table 3). Peridinin and zeaxanthin were not always detected; but where they were quantifiable in all triplicates, peridinin seemed to be reduced by 34% at 24-hr then recovered to a level comparable to the control at 48-hr in unfiltered seawater microcosms, and zeaxanthin was still reduced approximately 48% and 55% at 72-hr (p<0.05) in unfiltered and 5 μm filtered seawater microcosms, respectively (Table 3). Altogether above results suggest transient reduction but robust re-growth of diatoms and green algae in both pico, nano- and micro-phytoplankton communities.
Table 3. Percent decrease of the marker pigment concentrations (mean ± standard deviation of triplicate microcosms, and the probability) treated with 1.6 mg L−1 H2O2, as compared to the control without H2O2 addition, in microcosms with unfiltered and 5-μm filtered seawater.
Cell size dependent action of H2O2 was also evident, as the phytoplankton groups in 5 μm filtered seawater microcosms (dominated by picophytoplankton) experienced slightly greater percent inhibition and/or less robust recovery as compared to that in unfiltered seawater microcosms (which was a mix of pico-, nano- and microphytoplankton) (Table 3, and Fig. 3B and C).
A limited numbers of microcosms were exposed to 6.4 mg L−1 H2O2. As expected, 6.4 mg L−1 H2O2 completely removed 19′-bf pigment during the 72-hr study period, suggesting A. anophagefferens eradication. Chl a, fucoxanthin, chl b, peridinin were still exceeded by the controls at 72-hr by 64–71%, 93–97%, 5–28% and 49% respectively, and zeaxanthin went below detection limit during 24–72 hr (data not shown).
This study presented strong evidence, from culture and microcosm studies, that low dose of H2O2 (e.g. 1.6 mg L−1) effectively removed more than 90% of brown tide alga Aureococcus anophagefferens even at peak bloom density, without devastating most of the other potentially coexisting phytoplankton species and the natural phytoplankton community. Mechanisms of the differential susceptibility among phytoplankton and a realistic application scenario are discussed below.
A. anophagefferens demonstrated sensitivity similar to those of cyanobacteria. For example the EC50 were 0.3–0.4 mg L−1 for Microcystis aeruginosa and Trichormus variabilis and were between 1.1 and 1.7 mg L−1 for Synechococcus nidulans and two other cyanobacteria species on photosynthetic yield over 3-hr H2O2 exposure , in comparison with the EC50 of 1.39 mg L−1 on in vivo fluorescence based growth inhibition of A. anophagefferens over 3-hr exposure. Cyanobacteria has been shown to be more sensitive than most eukaryotic phytoplankton , , , , partly because of their prokaryotic photosynthetic apparatus . The high sensitivity of A. anophagefferens to H2O2 may be attributed to both its small cell size and the fact that it lacks cell wall. A. anophagefferens has only a diffuse layer of polysaccharide external to plasma membrane . As a result H2O2 can easily penetrate into the cell, and damage the cell by producing hydroxyl radicals which inhibit the photosynthetic electron transfer and the photosynthetic activity  among other effects.
The cell size dependent H2O2 sensitivity is likely caused by both the surface area to volume ratio being a function of cell size, and the non-selective reactivity of H2O2 and hydroxyl radical (·OH) product. The ·OH, a product of H2O2 interacting with ferrous ion via Fenton reactions  (Fe2+ may be formed via extracellular Fe(III) reduction ), is much more reactive than H2O2. It reacts with a wide range of organic compounds (alcohols, esters, unsaturated organics, aromatics, chlorinated hydrocarbons etc.) very rapidly with a second order reaction rate constant in the range of 107–109 M−1S−1 , . The ·OH potentially initiates radical chain reactions such as hydrogen abstraction and double bond addition, causing damage to biomolecules and cellular components on cell membrane, chloroplast ,  and DNA , eventually leading to oxidative stress and cell death. In terms of total cell surface area, cultures of the same biomass concentration but smaller cell size, as compared to larger-cell cultures, would have greater total surface area exposed to H2O2 and ·OH. As a result, the damage would be more extensive.
Other than cell size, the cellular structure, particularly the presence of rigid cell wall, may contribute to a species' H2O2 resistance. For example, the silica-mucilage cell wall of the diatoms ,  may have given Sc and Tw their H2O2 resistance (diameter 6.6 and 11.05 μm respectively, not affected by 6.4 mg L−1 H2O2), as compared to the athecate dinoflagellate Ac of similar cell size (diameter 9 μm, but showed >90% inhibition by 6.4 mg L−1 H2O2) (Table 1 and 2). The prymnesiophytes Ig lacks cell wall (and is often used in aquaculture for easy assimilation by larval animals because of Ig's small cell size and lack of tough cell wall) , , while Eh (CCMP 374) is non-coccolith forming strain (https://ncma.bigelow.org/, strain information); and both are more sensitive to H2O2 (3.6 and 3.7 μm respectively, showed >95% inhibition by 6.4 mg L−1 H2O2) than the diatoms of similar cell size e.g. Mpo (3.5 μm, 90% inhibition) and Tp (3.8 μm, 72% inhibition) (Table 1 and 2). The rigid cell wall, if present, potentially provides a first layer of defense against H2O2 and HO·, and allowing them to be inactivated before reaching the more sensitive and biologically critical components of cell membrane and organelles.
Likewise, Jeong et al.  found log-log relationship between the mortality rate of aquatic organisms (red tide dinoflagellates, diatoms, ciliates, copepods, fin-fish, brine shrimp and shellfish) and organisms' bio-volume, when exposed to hypochlorite, another small molecule oxidizing biocide. They further reported that diatoms were more resistant to hypochlorite than dinoflagellates even if they were smaller than the dinoflagellates in their study. This was attributed to siliceous cell wall and the large vacuole volume of diatom cells .
Hydrogen peroxide may be inactivated and detoxified by organisms' reactive oxygen species scavenging systems. Once H2O2 penetrates into a cell, reactive oxygen species scavenging systems would decompose and inactivate the excessive amounts of H2O2 , . Glutathione peroxidase, ascorbate peroxidase , catalase , and various antioxidants such as ascorbate , glutathione  and even mycosporine and mycosporine-like amino acids ,  likely participate in H2O2 and HO· scavenging. This, along with the capability of the cell to repair and replace the damaged biomolecules and cellular components, permits the culture to re-grow, as was observed in both the culture and the microcosm studies at relatively low H2O2 exposure.
Ex situ treatment of coastal algal bloom could be very costly given the enormous large size of water to be treated. For example if a bay water of 5×5 km2 with a depth of 1 m (2.5×1010 L or 6500 million gallons of water) is to be treated ex situ within 5 days, it would require a treatment capacity of 1300 million gallon per day (mgd), nearly 4 times that of Passaic Valley Sewage Commissioner, New Jersey, which is among the largest wastewater treatment facilities in Eastern US. Further, if the water is to be retained for 1 day before disposal, it would need 1300 million gallon reactor, representing an enormous size.
In situ treatment should be more feasible, although challenges exist. To treat brown tide bloom at 1.6 mg L−1 H2O2, one challenge is to disperse the concentrated H2O2 stock solution homogenously into seawater with minimal localized high concentration. In our study the stock solution (30% H2O2) was diluted 1000-fold before adding to the cultures. This dilution scheme requires an addition of 4.8-mm water containing 0.03% H2O2 to bloom water of 1-m depth (or 4.8 µm of 30% H2O2); and the wave action or a mixing device makes the additional 200-fold dilution to arrive at 1.6 mg L−1. The rate of chemical dispersal facilitated by wave action should be examined ahead of time, if possible, using hydrologic tracer chemicals such as sulfur hexafluoride (SF6) . In Lake Koetshuis cyanobacterial bloom control Matthij et al. achieved nearly homogenous dispersal at 2 mg L−1 H2O2 using 10% H2O2 stock solution . The mixing scheme was that computer controlled pumps (operated from a small boat) mixed 10% hydrogen peroxide stock solution with lake water at 500-fold dilution, which was then directly dispersed into the lake using a water harrow to obtain additional 100-fold dilution at 2 mg L−1 . The homogeneity was verified within 3-hrs of dispersal . Thus, this challenge is potentially solvable.
A second concern in in situ treatment is whether the efficacy of the treatment observed in the culture and microcosm studies is transferable in field applications, and further, what environmental factors may lead to variable success of bloom control. Since the OH radical is believed to be the active chemical species that attacks and kills the cells during H2O2 treatment, environmental factors that affect H2O2 decay and OH radical production likely also influence the efficacy of the treatment. Among other factors, Fe2+/Fe3+ and UV radiation could be important, as they would promote the conversion of H2O2 into OH radical through Fenton reaction (Fe2+ + H2O2 → Fe3+ + OH·+ OH−, Fe3+ + H2O2 → Fe2+ + OOH·+ H+)  and photolysis reaction (H2O2 + hγ = 2 OH·) , respectively. In our culture study Fe3+ was well controlled at 6.6 × 10−19 M by using 100 µM EDTA and 8.3 µM total iron, and no Fe2+ was externally added . In comparison, in natural seawater Fe3+ and total dissolved iron (FeT) vary over a range of 1–2 orders of magnitude. For example, Peconic Estuary (an urban estuary in Long Island Sound, NY) had FeT at 10–100 nM  and 28–237 nM averaging 114±81 nM, and Fe3+ at 1.1×10−20–4.7×10−19 M averaging 1.3x10−19 M, where salinity ≥26 parts per thousand . Wu et al. reported 0.45–6.2 nM FeT in northwest Atlantic coastal water from the continental slope to near the mouth of Delaware Bay (6.2 nM) . Oceanic surface seawater has lower FeT, typically at 0.02–1 nM . FeT and Fe2+/Fe3+ were not measured in our microcosm sample taken from Barnegat Bay, NJ; but they could be similar to those of Peconic Estuary, based on reports of FeT in river water that discharges to these estuaries, e.g. 926 µg L−1 in Metedeconk River in Aug. 2003  and >300 µg L−1 during 1960–1997 in rivers that discharge to Barnegat Bay , in comparison to a similar level of 400 µg L−1 in Peconic River for Peconic Estuary . In both culture and seawater microcosm studies more than 90% A. anophagefferens decline was achieved despite potentially up to 10-fold difference in Fe3+ concentrations in two types of media, suggesting limited variation in Fe3+ concentration and limited influence in shaping the outcome of bloom control in coastal water. Natural radiation (both UV and PAR, photosynthetically active radiation) likely enhance the treatment efficacy in the field. Barrington et al. examined laboratory-, mesocosm- and full-scale trials of H2O2 treatment for cyanobacterial bloom control in waste stabilization pond; they found significant synergistic effect of H2O2 addition with environmental factors (e.g. radiation) in the field trials . On the other hand, H2O2 may be consumed by excessive non-target materials such as dissolved humic substances leading to decrease of treatment efficacy. Quantifying the natural fluctuation of H2O2 and OH radical concentrations and carrying out small-scale field trials with a range of H2O2 addition would likely be informative to assess the potential outcome of the full-scale field application.
In terms of environmental risk of hydrogen peroxide in natural waters, Schmidt et al. reviewed and summarized that fish and fish eggs are relatively tolerant of hydrogen peroxide, other vertebrates and mammals are much more tolerant than fish, and that microorganisms and zooplankton in aquatic ecosystem are generally less tolerant than fish or other vertebrates  They determined that H2O2 ≤0.7 mg L−1 in receiving water is not a significant threat to organisms, environmental and public health (and to be used a criterion for water quality) . Indeed the reported toxicological data , , , ,  show that 1.6 mg L−1 H2O2 and transient exposure (as H2O2 decays rapidly in natural waters) should exert little harm to zooplankton , shellfish and shellfish larvae , , fish eggs, fingerling fish and fish of cold, cool and warm water , . Lake Koetshuis cyanobacteria bloom control with 2 mg L−1 H2O2 also evidenced relatively low environmental risk of this treatment to aquatic organisms, as the eukaryotic phytoplankton (including green algae, cryptophytes, chrysophytes and diatoms), zooplankton and macrofauna remained largely unaffected by the treatment . Our study further evidenced relatively low risk of H2O2 treatment to marine phytoplankton in that a) phytoplankton cultures of ≥2–3 µm cell size were largely unaffected, and b) in natural seawater microcosms the diatom and the green algae were only transiently suppressed and total chlorophyll a recovered and exceeded that of the control by 72-hr of H2O2 treatment Therefore, although some eukaryotic phytoplankton could be eliminated by the H2O2 treatment at 1.6 mg L−1 (e.g. the target organism brown tide alga and the prasinophyte Micromonas pusilla), there would be very low risk for the majority eukaryotic phytoplankton, zooplankton, fish, larval fish, and other larger aquatic animals.
It is logical to think that aquatic bacterial community could be most sensitive to H2O2 treatment, as H2O2 is also used as a therapeutic agent in controlling aquaculture bacterial infection . However bacteria sensitivity varies greatly and many factors including contact time, water quality and pH affect the inactivation of bacteria by H2O2 treatment . Standardized bacterial culture tests showed that some bacteria had their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) on the order of mg L−1 or higher. For example, 11 strains of 4 species of oral Streptococci had MIC and MBC of 3.2–14 mg L−1 and 3.5–28.2 mg L−1, respectively (for an initial 106–107 colony forming units per mL of logarithmic growth phase, trypticase soy broth, and 24-hr anaerobic incubation) . MIC of 469–2500 mg L−1 were observed for cultures of Bacillus subtilis, Bacillus stearothermophilus, Escherichia coli, Staphylococcus aureus Enterobacter cloacae, Serratia marcescens and Acinetobactev calcoaceticus(for an initial ≥106 CFU mL−1, in tryptic soy broth, 24-hr incubation) (E. coli had MIC of 2505 mg L−1) . Baldry compared the bactericidal, fungicidal and sporicidal properties of hydrogen peroxide and peracetic acid and found that H2O2 to be a poor bactericide but bacteriostatic effect was achieved at and above 0.15 mM (5.1 mg L−1) . Studies on marine bacteria were fewer; MIC was reported at 10–41 mg L−1 for four marine bacteria Vibrio alginolyticus, V. harveyi, V. parahaemolyticus and V. vulnificus in Mueler Hinton Broth and were 0.6–2.4 mg L−1 in 1.5% NaCl solution . Laboratory incubation of seawater (with 10 time lower bacterial abundance as compared to the in situ abundance) showed that natural background levels of H2O2 (0.1–1.35 µM, 3.4–46 µg L−1) could cause bacterial production reduction to 25% of its control over 24-hr, and induce 1–3.4% lysogenic (due to virus) bacterial mortality . Xenopoulos and Bird reported (for a humic lake in Quebec, Canada) that bacterial productivity were consistently suppressed by 3.4 mg L−1 H2O2 and were variably suppressed (dependent on the date and time of observation) at the exposure of as low as 0.0034 mg L−1 . Therefore, some marine bacteria species could be very sensitive, but others such as E. coli very resistant. Nevertheless, bacteria are expected to inoculate from surrounding waters and quickly reproduce and repopulate the treated water once H2O2 is sufficiently dissipated after treatment. Thus, long lasting impacts are not expected.
Cyanobacteria community could be most severely affected by H2O2 treatment, as was seen in the field work of Matthij et al. where 2 mg L−1 H2O2 eradicated cyanobacterial bloom of Planktothrix agardhii in the freshwater lake . However, cyanobacterial sensitivity to H2O2 also varied substantially among the species. For example, EC50 for photosynthetic yield (3-hr H2O2 exposure) were 0.3–0.4 mg L−1 for Microcystis aeruginosa and Trichormus variabilis but were 4-fold higher at 1.1–1.7 mg L−1 for Synechococcus nidulans and two other cyanobacteria species . Schrader et al. reported a lowest complete inhibitory concentration (LCIC) of 100 µM for sodium carbonate peroxide (equivalent to 32.5 µM or 1.1 mg L−1 H2O2) for off-flavor producing cyanobacteria Oscillatoria cf. chalybea but it was 10-fold higher (equivalent to 325 µM or 11 mg L−1 H2O2) for Anabaena sp LP691 . Kay et al. reported more than 85% bleach of chlorophyll in cyanobacteria Raphidiopsis sp. after 48-hr exposure to 200 µM H2O2 at 90 µmol m−2 s−1 but no significant bleach was observed in Anabaena sp under the same condition . Observing substantial species variability in H2O2 tolerance among cyanobacteria, Schrader et al. concluded that H2O2-based algaecide "may be less disruptive to the aquatic ecosystem by not eliminating all of the cyanophytes so quickly as to create low dissolved oxygen levels which could stress and kill fish" . In our seawater microcosm study the cyanobacterial population was not completely eliminated, but reduced about 50% by 72-hr of H2O2 addition (as compared to the control without H2O2 addition). Furthermore, the most sensitive cyanobacteria species, though eliminated by H2O2 treatment, likely get re-inoculated from surrounding water via natural water exchange, while the more resistant ones would persist and repopulate the treated water.
Hydrogen peroxide is rapidly decomposed into water and oxygen , , , , and does not produce persistent chemical residues. Cooper et al . observed the half-life of hydrogen peroxide in lake water at 4.4, 4.7, 6.4, 19.1 and 58.7 hr in unfiltered, 64 µm filtered (zooplankton removed), 12 µm filtered (large algae removed), 1 µm filtered (small algae removed), and 0.2 µm filtered (bacteria removed) waters, respectively. Matthij et al. found that hydrogen peroxide applied to Lake Koetshuis at 2 mg L−1 was degraded to 0.7 mg L−1 after one day and to below detection limit (∼ 0.1 mg L−1) after two days . Thus, we expect the concentration of H2O2, if applied at 1.6 mg L−1 to natural seawater, to be reduced to the natural background level within a couple of days due to decomposition and simultaneous dilution. The proposed concentration is indeed quite low as compared to a) the proposed receiving water quality criterion of 0.7 mg L−1 , b) the natural occurrence in rain water at e.g. 5–25 μM H2O2 in North Carolina  or up to 57 µM (∼ 2 mg L−1) at Bermuda Atlantic Time Series Stations , and c) up to hundreds nM background existence in surface seawater , . The decomposition of H2O2 potentially improves water quality by oxygenating the water column, facilitating dissolved organic matter degradation , and even inactivating algal bloom toxins . Further, in natural waters, UV-light could have synergistic effect with H2O2 , thus even lower dose than 1.6 mg L−1 H2O2 may be effective in brown tide bloom control.
Harmful algal bloom has become an increasingly important issue to the economic development and environmental sustainability, such that it demands both direct control methods and long term prevention measures. This study evidenced, from culture and microcosm studies, that 1.6 mg L−1 H2O2 effectively removed brown tide even at peak bloom intensity, and the other phytoplankton of >2–3 µm cell size remained largely unaffected by the treatment. Thus hydrogen peroxide is proposed as a natural and environmentally friendly agent potentially useful for brown tide control.
Prof. John Tiedemann at Monmouth University, NJ, collected Barnegat Bay water for us during his zooplankton sampling in the upper bay. Collection of seawater does not require specific permission; Prof. Tiedemann holds permits for his sampling of zooplankton, fishes, and crustacean, issued from New Jersey Department of Environmental Protection, Division of Fish and Wildlife Marine Bureau issued sampling.
Conceived and designed the experiments: VR LW. Performed the experiments: VR. Analyzed the data: VR LW. Contributed reagents/materials/analysis tools: LW. Wrote the paper: VR MT LW.
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79. Mullaugh KM, Kieber RJ, Willey JD, Avery GB (2011) Long-term temporal variability in hydrogen peroxide concentrations in Wilmington, North Carolina USA rainwater. Environmental Science and Technology 45: 9538–9542.
80. Häkkinen PJ, Anesio AM, Granéli W (2004) Hydrogen peroxide distribution, production, and decay in boreal lakes. Canadian Journal of Fisheries and Aquatic Sciences 61: 1520–1527.
81. Levy JL, Stauber JL, Jolley DF (2007) Sensitivity of marine microalgae to copper: The effect of biotic factors on copper adsorption and toxicity. Science of the Total Environment 387: 141–154.
82. Sym SD, Pienaar RN (1993) The class Prasinophyceae. Progress in Phycological Research 9: 281–376.
83. Tomas CR (1997) Identifying marine phytoplankton. New York.
Is the Subject Area "Phytoplankton" applicable to this article?
Is the Subject Area "Diatoms" applicable to this article?
Is the Subject Area "Hydrogen peroxide" applicable to this article?
Is the Subject Area "Dinoflagellates" applicable to this article?
Is the Subject Area "Pigments" applicable to this article?


Two well known German producers team up once again to prove that Germany has surely a lot to offer when it comes to progressive trance.
Marc van Gale is well known for his heavy basslines which always bring a great techy touch to his tracks. 'Phoenix' is no different and is definitely rising fast from the flames of these guy's studio!
ASKII's tracks are always concentrated on the emotional side of each track which works perfectly with the driving sound of Marc van Gale. The breakdown is nothing short of amazing, deep and most of all, not typical. All the right things settle into each other in this amazing collaboration. This surely deserves the attention of any major Progressive Trance DJ!


I believe he meant the query id's that the engine uses, and not the auto increment id's. Wez's response was accurate, we'll overflow at some point. This is basically because PHP was designed with short requests in mind. We could probably fix it relatively easily for ZE2.


CHARLOTTE, N.C. – The Queen City hosted the NBA All-Star Game in 1991, but that was when the city didn't have enough bars and restaurants to host all of the fans.
Now, restaurants, bars, museums and other attractions line the streets throughout Center City.
Former Mayor Pro Tem Lynn Wheeler said when the All-Star Game was in Charlotte in 1991, the All-Star Committee wanted to provide the thousands of out-of-town guests with more food and drink options.
"There was no activity or life in downtown Charlotte, none," Wheeler said.
Offices and storefronts in uptown were converted into pop-up restaurants and bars to give the city some hustle and bustle, Wheeler said.
"It looked real, but it was kind of a joke," she said.
An estimated 9,000 visitors were expected for the game in 1991. For this year's All-Star Game the Queen City is preparing for 150,000 people.
Tickets to get into the game are more than $500 for upper-level seats Sunday night.
In 1991, current Mayor Vi Lyles took her son to the game for less than $50 at the coliseum on Tyvola Road.
"It was basically (where) a town people came into work and then went home," Lyles said.
"Having professional sports makes the city more mature but also a more exciting place to be," Lyles said.


text:
Falstaff är en italienskspråkig opera med musik av Michael William Balfe och libretto av Manfredo Maggioni. Operan hade premiär den 19 juli 1838 på Her Majesty's Theatre i London.

Inspelningar
Falstaff Marcel Vanaud (Falstaff), Majella Cullagh (Mrs Ford), Sam McElroy (Ford), Barry Banks (Fenton) RTÉ Concert Orchestra dirigerad av Marco Zambelli i samarbete med Opera Ireland för RTÉ

Källor

Operor av Michael William Balfe
Italienskspråkiga operor

redpajama_set_name: RedPajamaWikipedia


N.B. This is a template that was used to create specific regional press releases, hence exact figures are blank. For more information or for a specific regional release, please email Andrew.walker@ageuk.org.uk.
Miriam Margolyes and UK Digital Champion Martha Lane Fox back campaign to donate old computers to Age UK as new figures show (x%) of the people in have at least one or more unused PC or laptop.
Age UK is helping older people to get online in 2011 by asking anyone with unused computers at home, including celebrities, business leaders, politicians and most importantly everyone in the , to make a New Year's resolution to donate their old PCs and laptops to an Age UK charity shop. The donated computers will be refurbished, with the memory wiped and new software installed, and the profits Age UK makes by selling the computers on will go towards helping people in later life to start accessing the benefits the Internet has to offer.
New figures(1) from Microsoft, who is also supporting the appeal show that people in the have at least one or more old computers around the house, and that overall there are an estimated 30 million PCs and laptops lying unused in homes across the country. With six million people aged 65+ having never been online Age UK is calling on everyone to donate old PCs (although not monitors) and laptops, including computer power cables, to their nearest Age UK shop. Once donated their PC or laptop will be professionally refurbished and sold on, with Age UK receiving 50% of the profits, all to help older people get online. To find your nearest participating Age UK shop visit http://www.ageuk.org.uk/donate-pc or call 0800 169 65 65.
With people in the admitting to simply throwing away their old PC, donors will have the added peace of mind that their personal data will be securely wiped to international standards and that they will be doing the environment a favour as their unused computer will be recycled to be used again. Most importantly, their old PC or laptop could make a huge difference to the life of an older person by introducing them to the benefits of the Internet such as keeping in touch with friends and family, cheaper shopping online and pursuing hobbies through Age UK training classes.
Age UK aims to help some of the six million people 65 and over who have never been online before to start using the Internet through a number of means, including week long campaigns such as itea and biscuits week and myfriends online week. The charity also provides support to over 190 local organisations through the charity's Digital Inclusion Network and also helps fund local technology training through Digital Inclusion grants. The money raised from the computer refurbishment scheme will go towards these initiatives and help older people across the UK get online.
The donate a PC scheme was launched last month as part of GO ON: Give Someone Their First Time (www.get-someone-online.com), an initiative led by Microsoft and a number of other business and organisations as part of Race Online 2012 The campaign aims to inspire regular Internet users to encourage people in their lives who are not online to give the Internet a go by passing on their skills to train people, register a friend or family member on a training course or by donating a PC.
Age UK manages a number of UK-wide digital inclusion programmes, including the Digital Inclusion Network consisting of 190+ partner organisations and Connect with IT, a comprehensive digital inclusion campaign involving itea and biscuits week, myfriends online week, Internet Champion of the Year competition and IT Volunteering. More than 200,000 people in later life have been helped to date.
Microsoft Advertising provides advertisers and publishers with media, tools and services designed to drive deep and profitable engagement with their audiences. The Give Someone Their First Time Online campaign is a natural extension of Microsoft's 'Britain Works' initiative to encourage those online to easily help others get online. Microsoft Advertising led this project and donated millions of page impressions to this campaign across its network of online properties.


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text:
Port of Port Townsend commissioners to meet again on leasing policy
by Jeannie McMacken
Thursday, July 12, 2018 2:16pm
NewsJefferson CountyPorts
PORT TOWNSEND — Port of Port Townsend commissioners expressed frustration at the lack of progress in developing a leasing policy during a public workshop session Wednesday morning.
Commissioners called on staff to gather samples of other ports' leases as a template for review and set another public hearing to request public comments on the draft leasing policy. It is scheduled for 5:30 p.m. July 25 at the port commission building, 333 Benedict St.
This was the third draft of the port's policies and practices guidelines and was made available to commissioners Tuesday evening for review. Other drafts were presented and discussed at June 13 and June 27 public workshops.
"It's the commission's job to create strategic direction," Commissioner Bill Putney said. "The staff's job is to give us a helping hand. I don't feel that I need to sign off on something that I don't think is as good as it could be."
Commissioner Pete Hanke was aggravated with the lack of progress and the lack of a clear direction.
"What's confusing is that we are working on one policy. This is the third meeting we've had on this one policy. We have a whole boatload of stuff to get through," he said.
"If we can't come up with a way to expedite this process then we aren't going to get through this. I would encourage staff to really figure out how to streamline this process.
"In the business policy," he continued, "you talk about how we are going to follow our business plan. We don't have a business plan.
"If we keep doing this with comments in the margin, do you know how much time it will take to come up with a business plan?
"I would encourage us to discuss how we are going to streamline these policies. It still doesn't work. I'd like it on a more timely basis, not the night before."
Putney said the policies are the basis for the relationships the port has with its tenants.
"A lot of our anxiety and struggles we have communicating with tenants is based on the fact that they don't know what the heck we're thinking about or doing from day-to-day," he said.
"If we have good policies, whether they like them or not, and they are not ambiguous or to the point, then that's a basis for going forward."
Commissioner Steve Tucker referred to the Washington Public Ports Association (WPPA) membership dues and said it is a way to get the collective wisdom of all the ports. He directed staff to obtain sample leasing policies from them for review and discussion.
"Most of this stuff is normal stuff that we haven't been keeping up with because we're isolated out here," Tucker said.
"We need to normalize our leases to modern 21st century standards. We've got an attorney that represents a lot of ports and this is a bread-and-butter issue. This would be a good person to go through the WPPA guidelines and say this works, this doesn't."
Tucker requested that port attorney Frank Chmelik of Chmelik, Sitkin and Davis be asked for input.
Executive Director Sam Gibboney suggested that leases should be tied to the consumer price index (CPI) plus 1, then re-examined in five years, which prompted debate among the commissioners about a competitive market rate.
Greg Englin, director of Operations and Business Development, said that there is no "normal" for rent adjustments.
"Lots of ports are grappling with this right now," he said. "CPI isn't always enough."
Hanke referenced three current leases, pointing out that all were on very different programs.
"We were looking at doing improvements to the Armory building (but) we weren't good stewards of the triple bottom line issues and we lost a huge heritage marker," he said.
"Yet we are talking about spending a gob of money for Washington Department of Fish and Wildlife (WDFW) because they are threatening to leave because they don't like the creosote smell on their clothes.
"It boils down to who is sitting in chair making the leases. They are all going to be different."
Hanke said he gets confused when the discussion becomes the financial recovery of assets.
"You aren't going to rent something out here that will recover the assets for the breakwater, the docks, the stormwater, or paving the yard," he said.
"None of those improvements or rehabilitation are going to be incorporated in the market rate. We need to be careful how we use these words. If someone says I'm going to make sure all those cost recovery items are wrapped up in the leases, my guess is that you are going to be quite a bit higher than market rates."
Gibbny pointed out that, in spite of a lack of policy, "our yard occupancy is at a five-year high."
Jefferson County Editor/Reporter Jeannie McMacken can be reached at 360-385-3225 or at [email protected]
Carlsborg 66-manufactured home park decision expected by July 26
Port Angeles city begins to consider possible cuts; exercise aimed at being prepared if needed, officials say

redpajama_set_name: RedPajamaCommonCrawl


* As Ching Ming Festival in 2015 falls on a Sunday, the following day will be designated as a general holiday in substitution. However, as the day following Ching Ming Festival and Easter Monday fall on the same day, the next following day that is not itself a general holiday will be observed as an additional general holiday.
† The Government has, by legislation, designated 3 September 2015, the 70th anniversary day of the victory of the Chinese people's war of resistance against Japanese aggression, on a one-off basis as an additional Statutory Holiday and General Holiday for 2015.


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text:
Higgins, Tanya
About the authors: Dr. Tanya Higgins received her PhD in Cultural Anthropology/Peace Studies from The Union Institute, Cincinnati. She currently teaches at Saint Leo University, Williamsburg, VA. She is a member of the International Peace Research Association, and the Committee on the Administration of Justice in Belfast. Dr, Nancy Brown Diggs received her PhD from The Union Institute, Cincinnati. She has spent time in Great Britain and lived in Europe, and is the author of five books, including Meet the Japanese (Renaissance, 1991), and Steel Butterflies: Japanese Women and the American Experience (SUNY Press, 1998).
Look at Life in Northern Ireland - How Do Women Live in a Culture Driven by Conflict?
This study, written from an anthropological standpoint, focuses on women's lives in Northern Ireland. It examines the lives and work of a range of women, and illustrates some of the historical and political backdrop. It discusses a number of women's initiatives in the voluntary sector to illustrate the work they are doing to achieve a peaceful outcome to the age-old problems. Interviews were conducted with women, ecumenical groups, Belfast City Council Members, Ian Paisley, Jerry Adams, and human rights activists. The book will interest those in women's studies, peace studies, and Irish studies.


Geography Publications, 24 Kennington Road, Templeogue, Dublin 6W.
Irish Academic Press, 8 Chapel Lane, Sallins, Co. Kildare.
Irish Manuscripts Commission, 45 Merrion Square, Dublin 2.
Royal Irish Academy, Academy House, 19 Dawson Street, Dublin 2.
Wordwell Books, Unit 9, 78 Furze Road, Sandyford, Dublin 18.


text:
Q: FirebaseError: Function Query.where() called with invalid data. Unsupported field value: undefined I want to get only the document specified by where.
Store the email address registered in the uid property as a value in the Firestore at the time of new registration.
    async signUp() {
      const db = firebase.firestore();
      await this.$store.dispatch('signUp', { username:this.username, email:this.email, password:this.password });
      await db.collection('myData').doc(this.username).set({
        uid: this.email,
        email: this.email,
        myWallet: 1000
      });
      this.$router.push('/home');
    }

async signUp({ commit }, userInfomation) {
      try {
        await firebase
          .auth()
          .createUserWithEmailAndPassword(
            userInfomation.email,
            userInfomation.password
          );
        const user = firebase.auth().currentUser;
        await user.updateProfile({
          displayName: userInfomation.username,
        });
        commit('setUserName', user);
      } catch (e) {
        alert(e.message);
      }
    },

  mutations: {
    setUserName(state, user) {
      state.userName = user.displayName;
    },

actions: {
async getMyWallet({ commit, state }) {
      const uid = state.updateUserName.email; //Information on the logged-in user is stored in updateUserName.
      const db = firebase.firestore();
      const doc = await db
        .collection('myData')
        .where('uid', '==', uid)
        .get();
      commit('getMyWallet', doc);
    }
}

When I ran it, I got the error written in the title.
Is it written incorrectly?
Is there any other good way?
    async getMyWallet({ commit }) {
      firebase.auth().onAuthStateChanged(user => {
        const uid = user.email;
        const db = firebase.firestore();
        const doc = db
          .collection('myData')
          .where('uid', '==', uid)
          .get();
        commit('getMyWallet', doc);
      });
    },

When I rewrote the getMyWallet part, I got a new error.
Error details: doc.data is not a function

redpajama_set_name: RedPajamaStackExchange


Stealth pivot is a compact and innovative pivoting hinge system, that can be fitted inside virtually any door leaf. The pivot hinge features a high-tech comfort closure that works in all swing directions up to 360°. When fitted and installed, the hinge remains invisible, hence the name "Stealth Pivot".
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This pivot door hinge is mounted straight on top of the finished floor and underneath a solid or reinforced ceiling surface, without the need for any built-in fixtures. The minimal anchoring (2 Hilti screws and plugs +- 4.5 cm deep) allows for easy installation on any type of surface. The hinge mounts are equipped with our patented 0° positioning system. Optional magnets and 1-way accessories are also included for installation when necessary.
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The axis point can be positioned at either 80 mm or 178 mm by simply turning the hinge around in the cavity inside the door panel.
The self closing technology will position the door at 0° when installed correctly. The hinge mounts feature a correction & adjustability system with hexagonal bolts to fine-tune the panels position at 0° after installation. We also include a set of magnets to ensure that the positioning at 0° is guaranteed after installation.
Installation of the magnet(s) accessories are optional.
The advised joint dimensions are based on a completely square (rectangular) opening. Please read our detailed instructions regarding dimensions & joint calculation in the instruction manual.
Delivered as a complete set with all the necessary accessories, right up to screws and plugs.
180° or 360° swing operation with a silent 90° hold function in all swing directions 90° | -90°.
We include a magnetic 2-way door positioning accessory that can be fitted on top of the door with a small counterpart against the ceiling for positioning purposes. We also include an optional 1-way accessory. This 1-way configuration both positions the door at 0° and blocks the door when 1-way 90° swing operation is necessary or desired.
The pivot axis can be positioned from 1/3 up to the centre of the door leaf with. Doors with a central axis position can swing 180° or 360°.
The advised joint dimensions are based on a completely square (rectangular)opening. Please read our detailed instructions regarding dimensions & joint calculation in the instruction manual.


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text:
By Aimee Walleston
Aimee Walleston
More Stories by Aimee Walleston
In 1968, Argentine artist Marta Minujín found her nose pressed against the window of the intimidating social web of New York City (and its even more Byzantine art world). But rather than become a mere spectator, Minujín used her outsider status to her advantage, and conceived of a genre-defining artwork that helped her make sense of a world where knowing the right social moves was they key to upward mobility. "I got a lot of fame [at a young age]," recalls the artist, "for work I did in Buenos Aires and in Paris. I was interested in fame and in media. When I arrived to New York, nobody knew me." That soon changed, and in response to her interest in the media theory of Marshall McLuhan, as well as her intrigue with the New York cocktail party scene, she created the multimedia happening and film piece, Minucode (1968). For the piece, Minujín staged four separate cocktail parties with elite members of the worlds of politics, business, art and fashion. The work was commissioned by Stanton Catlin, the original director of the art gallery at the Rockefeller Foundation-funded Center for Inter-American Relations (now the Americas Society). 42 years later, a portion of the remaining piece is again being exhibited, through June 12, at the Americas Society.
IMAGE COURTESY THE ARTIST.
Intent on reversing the power structures inherent in social gatherings, Minujín began Minucode by placing advertisements, in the form of questionnaires, in a variety of New York City newspapers. Each questionnaire invited participants to code themselves by placing their occupation under Business, Politics, Fashion or Art. The questionnaire, to give an accurate depiction of the time the piece was written in, also asked participants to list "What type of materials turn you on?" and, as a sub-question: "do you like to play with your shadow?" Despite this playful manner of questioning, which one would think would make the political set run for the hills, the artist received roughly 1,000 mailed-in questionnaires. Dividing out the respondents to their respective professions, in the third week of May in 1968 the artist created a series of four cocktail parties (only business people would attend the "business party," etc.). When questioned as to why she felt the piece was so thoroughly accepted by guests "It was because I did it at the place that was [affiliated with Rockefeller," says Minujín. "I did it in the right place, at that moment. It [Center for Inter-America Relations] was a snobbish place, so that's why the politicians, who never came to [art events], came to these. [And] for me, the social situation was the work of art."
What occurred at these parties, claims Minujín, was a startling similarity in codes of behavior. "The only difference was the clothing," claims the artist. "The politicians were all in black, the business people were all in brown, the fashion people were all in pink and gold (with Diana Vreeland as headmaster), and the art people (John Perrault and Al Hansen, among many others) were in red and blue." Minujín filmed each party, and then displayed the films in the gallery space, dividing the film of each party into intervals. Of the visual experience, says Minujín "It was 10 minutes black, 10 minutes brown, 10 minutes pink and gold-like that." Unfortunately for the films, after the artist left New York, she got caught up in another social milieu, to dire consequences: "I became a hippie and traveled all over the world-and [all the Minucode films] got lost. It's a real miracle we found the film from one of the projectors, containing images of the four cocktails from one angle. [It] was found in LA, and someone who worked at Americas Society had it and gave it to (deceased art critic) Olivier Debroise. Then it was found by Cuauhtémoc Medina in Mexico (Tate curator at the time and friend of Debroise), who took it from [Debroise's] room after his death and brought it to me in 2006."
The film now showing at the Americas Society is projected oversized on four walls, and just by viewing one's shadow implicates you as an attendee of each cocktail party. The films come with still images from the parties, mostly portraits, and an interactive slideshow that the original guests created with artist Tony Martin, the then Visual Director of The Electric Circus. A panel discussion held earlier in the month was titled "The World is So Boring," in honor of New York Times critic Grace Glueck, who borrowed this quote—"The world is so boring, I have to think of things continually to keep myself tense"-from artist Nam June Paik, and who wrote extensively on Minujín's work. Included on the panel was the artist Carolee Schneemann, though Minujín laughs: "Carolee isn't even sure she came [to Minucodes]! There was a lot of drinking then. We were all drunk." But, as this show proves, friends-in attendance or absentia-are always key to any art movement, not just the movement of "happenings" that Minujín is most often credited to. Also exhibited in the show are letters and articles related to Minujín. One particularly poignant letter came to the artist by way of critic and philosopher Pierre Restany, who awarded Minujín the 1964 Torquato Di Tella Institute prize. The note advises Minujín to keep her spirits up in the face of New York's "whole subtle blend of social standing, art world politics, self-interested friendships and scheming."
MINUCODES IS ON VIEW THROUGH JUNE 12. THE AMERICAS SOCIETY IS LOCATED AT 680 PARK AVENUE, NEW YORK.
Americas Society
Marta Minujín
minucodes


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text:
Q: Auto-refresh div using jQuery doesn't auto-refresh Can someone help me to function this?
The "call.php" page loads the "table__data.php" on "content_div" div, but it doesn't automatically refreshes the div in 3 seconds. I'm creating a page where it can display queue tickets being served.
Here's my code for table_data.php

  Ticket Number
  Counter

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define('DB_PASSWORD', '');
define('DB_NAME','dswd_qms');

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$sql = "SELECT a.ticket_id, a.ticket_no, a.proceed_to
                FROM qms_tickets AS a
                WHERE a.ticket_date = CURDATE() AND a.ticket_status = 2 OR a.ticket_status = 4 AND enabled = 1";
$result = mysqli_query($link,$sql);
if($result->num_rows>0){
  while($row=$result->fetch_assoc()){
    echo "
#".$row["ticket_no"]."	".$row["proceed_to"]."
";
  }
  echo "
";
}
else{
  echo "0 Results";
}
?>

And here's my code for call.php

A: The solution you tried is not right. Try this one,
// $(document).ready(function(){}); is when the document is ready or loads first time
$(document).ready(function(){});

// For loading page in certain intervals
setInterval(function(){
    $('#counter_div').load(' #counter_div');
}, 3 * 1000); // 3 * 1000 == 3 seconds


text:
Crawford-Postol brings between 50K to 60K PPV buys
September 2nd, 2016 - Comments Closed
By Dan Ambrose: As many boxing fans expected, the July 30 unification fight between WBO light welterweight champion Terence "Bud" Crawford (29-0, 20 KOs) and WBC 140lb champion Viktor Postol (28-1, 12 KOs) resulted in low pay-per-view buys on HBO. According to Dan Rafael of ESPN, the fight generated between 50,000 and 60,000 pay-per-view buys. This is what Top Rank promoter Bob Arum reportedly told Rafael. The gate for the fight was a good one with it doing almost $750,000.
The 84-year-old promoter lost $100,000 on the fight, which wasn't a lot considering the money that went into the card. Arum feels like it was well worth it due to him being able to have Crawford-Postol fight when he wanted the fight to take place, and he was also able to have featherweight Oscar Valdez's fight televised as well.
Crawford won the fight by a 12 round unanimous decision by the scores of 118-107, 117-107 and 118-107. The fight took place at the MGM Grand in Las Vegas, Nevada.
Terence Crawford's resounding decision win against Viktor Postol to unify junior welterweight world titles on July 23 at the MGM Grand in Las Vegas was a money loser, as most expected it would be, but it did not lose as much as Top Rank promoter Bob Arum thought it would. Arum told ESPN.com that the fight generated between 50,000 and 60,000 buys on HBO PPV but a stronger-than-expected gate helped offset losses, which he said amounted to about $100,000.
"We lost a little money but very little," said Arum to ESPN.com. "Certainly if we had a rights fee that would have been the way to go but if I had looked for a rights fee I'd still be waiting for a phone call. Look, I got the fight on. It was an important fight for Terence's career and he looked great. And (Oscar) Valdez won his (featherweight) title on the card, so it was worth it. I probably lost around $100,000 but the gate really surprised us. We were projecting it to be much lower but it did almost $750,000 and that really helped on a fight like this."
Crawford looked good at times against Postol, but it was far from a great performance from the Omaha, Nebraska native. Crawford played it safe too much in the fight, and did too much moving in the second half of the contest. Instead of Crawford looking to close the show, he chose to run around the ring. The crowd was patient with him by not booing a lot, but there were still many unhappy boxing fans who didn't like the way that Crawford was sticking his tongue out at Postol in the 12th while running from him. It was not the kind of performance that you'd like to see from someone who is being pegged as a future PPV attraction.
If you look at how Manny Pacquiao fought his entire career with him making it exciting with his action packed fights, Crawford was on the opposite side of the spectrum with him playing it safe and looking to do just enough to win the rounds. In other words, it was not a Golovkin-esque or Pacquiao-esque performance from Crawford.
With the way Crawford fought so cautiously against Postol, he may have ruined his chances for a fight against Pacquiao. He may have also ruined it for himself to attract more boxing fans to want to see his fights. Crawford needs to realize that in order to win over more fans, he's got to become an exciting fighter to watch like Golovkin. Crawford's counter punching style of fighting is not thrilling to watch. It's about as exciting to watch as sitting and watching paint dry in the afternoon sun.
Bob Arum wants to make Conor McGregor vs Terence Crawford fight
If Arum wants to turn Crawford into a PPV attraction, then he needs to sit him down and tell him how he needs to fight from now on. Crawford has to takes more risks for him to produce knockouts because he's not going to be able to become a PPV attraction fighting the way he's doing right now. It would obviously make Arum a happy man if Crawford could become a PPV attraction for him, because he's going to need someone to replace Pacquiao when he retires for good. There isn't anyone in Arum's stable that can become a PPV by right now.
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