Calculating the coordinates of the 3D point corresponding to a depth reading is straightforward trigonometry – here's a quick refresher – but the accuracy of the results depends on several factors.
This method establishes the intrinsics solely for the colour camera.
Although it resolves to sub-pixel accuracy, it does so on a single frame, which is imprecise. The results of 3D calculations are extremely sensitive to errors in the field-of-view: A one-degree error in the vertical field of view translates into >11mm error at 1 metre. Concomitant errors in the horizontal field of view make matters worse and they are quadratic in the depth.
The depth stream is synthesised by the stereo depth module and the vision processor. Imperfections anywhere in the chain (unforeseen distortion, varying refraction at different wavelengths, heuristics in the algorithms, depth filtering) may negatively affect the accuracy. One cannot assume that an apparently perfect colour image will produce ideal results in the depth map.
By averaging depth measurements over a period, errors in precision can be eliminated. Averaged over 1'000'000 measurements, my out-of-the-box D435 reports a range of 980.70mm – an error of 19.3mm. This is within the specified accuracy 2%=20mm but increases quadratically, as is to be expected. Fortunately, this non-linearity appears to be constant for a given camera and once determined, can be eliminated.
The focal point of the depth map is supplied in the Intel RealSense D400 Series Datasheet, for a D435 it is defined as being 3.2mm behind of the glass. Presumably due to the manufacturing tolerances of ±3%, the focal point may in reality be tens of mm away.
No matter how precisely the camera is mounted, there will be errors between the mounting and the camera's true central axis. Knowing them improves the accuracy when translating from the camera frame to the parent (vehicle or world) frame.
I have written a program that calibrates a camera based solely on measurements in the depth stream. It derives all the parameters discussed above by making several observations of a target with known dimensions. A much higher degree of accuracy is obtained by averaging over a large number of measurements. The optimal parameter values are then calculated, as a single problem, with a non-linear solver.
The comparisons presented above use the Z-range as the metric, as this is the metric in the reference documentation. The Z measure alone is only part of the answer, a more realistic metric is the 3D error of the point: the vector between the truth and the 3D point determined by the camera and software. Futhermore, just supplying a number doesn't tell the whole story. Traditional error analysis supplies descriptive statistics, which give a value and a confidence known as the 68–95–99.7 rule, which allows us to make statements like "The error will be no more than Xmm 99.7% of the time" (3-sigma, or 3σ).
what this shows is that at 1.5 metres, the coordinates of the 3D point will be between 1'447 and 1'553 from the camera 99.7% of the time.
A depth camera measures the distance from the camera to a point in 3D space. For a given point, the camera supplies the row and column on its 'screen' and the depth towards the point. It is worth pointing out here that classic depth cameras like the Kinect supply the length of the ray; RealSense cameras supply the range, or Z component.
Notice the 'Rows-1' because there are 479 intervals between 480 pixels: row 239 points just under the horizon and row 240 points just above the horizon.
The calculations for the X-coordinate are identical, replacing 'Vertical' with 'Horizontal' and Z is simply the supplied range.
The NEO-M8P module series introduces the concept of a "Rover" and a "Base Station". By using a correction data stream from the Base Station, the Rover can output its relative position with stunning cm-level accuracy in good environments.
An old dog, I was wary of "in good environments". That RTK is capable of centimeter accuracy when stationary and with a horizon-to-horizon view of the sky, I have no doubt; but what about in a less GPS-friendly environments? This article is the result of real-life testing in my garden, cluttered by surrounding buildings and vegetation..
in particular how would it perform in less-than optimal conditions, so I devised a series of experiments, which I have named for the purposes of this discussion.
Open. Stationary for 24 hours in the middle of the lawn, with a decent view of the sky. A base-line test to determine the system performance.
Sky270. The receiver is next to the corner of a building, 90° of sky are obscured.
Sky180. The receiver is close to a wall of a building, 180° of sky are obscured.
Sky090. The receiver is in a corner of a building, 270° of sky are obscured.
Canyon. The receiver is between two buildings with a heavy tree canopy, most of the sky is obscured.
Mobile. The receiver is moved around the garden, stopping for 10 seconds at a known location in each of the previous tests.
Tests 2-6 are performed for an hour. As described later, I discovered that the receiver needs 25-30 minutes to settle on a solution and these data were removed.
All the tests are made with the antenna 54cm from the ground.
My rover was simply a low table in the garden, with the antenna 54cm off the ground.
In what follows, I am focussed solely on horizontal position – the X, Y values; I ignore altitude as it is only relevant for surveying and aviation.
All my calculations were performed in 64-bit floating point which gives ~15 decimal digits of precision.
The raw GPS data from the receiver contains latitude/longitude values. To convert these into distances I use Vincenty's formula. I validated my implementation against 500'000 known distances, which are precise to 0.1µ metre.
Each test produces 5 results.
It is worth noting that the 'best' fix is 4.
SVs is the number of satellites in view. I configured the rover UBX-CFG-NMEA to high precision mode (to output 9 digits of precision on latitude and longitude) and as a result considering mode is disabled. It is unclear whether satellites-in-view is those seen or those actually used.
hDop is the horizontal dilution of precision created by the constellation geometry.
ErrorLat is the distance in millimetres from the average centre of all the readings. Similarly ErrorLon.
ErrorLatLon is Euclidean distance from the measured point and the averaged centre of all the readings.
The ErrorX values are calculated using Vincenty's Formulæ.
Limit is simply a reminder of the percentages associated with the number of standard deviations.
σ is the standard sigma calculation, the square root of the variance.
Out is the actual number of measurements that exceed the CEP below.
CEP is obtained by finding the number of samples 'Out' which exceed the limit %.
The difference between σ (a statistical calculation) and CEP (the true value for the data set in question) is readily explained: The statistical σ is valid only when the data are normally distributed (a Gaussian). Even over 24 hours, GPS readings are not Gaussian because the average is not stationary. Disraeli's quip remains as true as ever.
A point's colour indicates its age as hue corrected for the human eye. First blue, then green, yellow, orange and finally red.
The receiver, antenna and PC are on a low table in the foreground.
The receiver is in Fixed mode 71% of the time.
and in both cases takes some 20 minutes before settling down.
I note that 20 minutes is the time that it takes the receiver to lock on cold start (details in Lessons Learned below) and postulate that momentary interference can cause a complete loss of the solution.
There were 4 such events in the 24-hour test. 4 in 86'400 = 1 in 21'600; a frequency less than 4σ, so I sought an explanation.
Which is what I expected and much more reasonable.
The receiver is against the NW corner of the house, 90° of obscured sky.
The receiver is slightly more in Float rather than Fixed (4.63 average quality). The 3σ CEP is 54 mm.
There is significantly more longitude error than latitude.
The receiver is near the NW wall of the house, half the sky is obscured.
The receiver is continuously in Fixed mode. The 3σ CEP is 43 mm.
The CEP is better than the Sky270 test, where only 90° of sky were obstructed. I attribute this to the fact that due to the lay of the land, the angle of the apex of the house is much larger when viewed from a corner. Additionally the sky view away from the house in this position is a little more cluttered.
The receiver is in a corner of a building, facing SW, 270° of sky are obscured.
The receiver is in Fixed mode for the whole hour. The 3σ CEP is 185 mm.
The deviation shape clearly reflects the SW direction of the corner.
The wide-angle lens gives the impression that there is a wide view towards the camera. This is not the case, the two houses' walls are almost parallel, some 12 metres apart and the canopy almost reaches to above the camera.
The receiver never achieves Fixed mode. The 3σ CEP is 135 mm.
I walked around the garden, pausing 10 seconds at each of the SKYNNN points to hold the GPS at a marked position.
The red points are the 9 nearest points to the average of each location.
The receiver was in Fixed mode 7% of the time.
The average position error when moving is 19 mm.
Here are some tips which might be useful to those envisaging the C98-M8P solution.
The last message-type received. This is particularly useful to confirm that you are receiving RTCM messages, where you will see the field display UBlox-NMEA-RTCM in quick succession.
UBlox stress repeatedly that the solution's accuracy depends on the antenna quality. I verified this and was unable to get the receiver to converge to 'fixed' mode (the highest accuracy) with the supplied patch antennas, so I bought a pair of Garmin GA38.
After 52 seconds the error is momentarily down to 24 mm, but it quickly rises to 1'400 mm, thereafter gradually getting close to zero over the next 13 minutes. It again wanders up to 200 mm over 5 minutes and achieves first Fix at 25:54. It finally alternates between Fix and Float for a couple of minutes before permanently settling to Fixed at 26:47. All this is perfectly reasonable, given the calculations involved.
The takeaway is that you should give the receiver half an hour to warm-up before you can expect accurate results. Note also that seeing it switch to Fixed is not a guarantee that it has completely settled.
It is apparent from the Sky090 test results that Fixed mode is an indicator of better quality but not a guarantee. All that can be said is that if the quality is 4 or 5, it's RTK; lower values are standard GPS.
On a 7.45 V battery, the base station consumes ~0.077 A = 0.573 W.
At 12.58 V, the rover consumes 0.066 A = 0.83 W.
So the evaluation board seems to use a linear regulator and I imagine that a non-negligible amount of that power goes to the blinking LEDs.
At closer to 3.5 V, you can assume a power consumption base or rover << 0.5 W.
As I discovered in the Sky360 test, unexpected interference can cause the unit to lose the RTK solution. The application can detect when this occurs by observing a Quality < 4; the consequence is that the position accuracy will be significantly degraded for the following 20 minutes.
Although not relevant for my use-case, I nonetheless tested the maximum baseline distance by driving away from the base station with the unit on my dashboard.
This limitation is certainly not due to the (amazing) UHF radio, I drove 13 kilometres away from the base and the RTCM stream arrived faultlessly during the whole journey.
There seems to be some confusion about precision and accuracy of the base station. Given the non-Gaussian nature of GPS measurements, acquiring a TRUE position (whatever that means) by averaging would take weeks (months?) simply because the precision of the average depends on the 'Gausian-ness' of the data. The base station's absolute coordinates, insofar as they are within metres of the truth, are irrelevant because the base transmits only satellite relative errors to the rover. The rover uses these relative numbers to adjust it's solution; the accuracy of the result is not contingent on the precision of the base. Given that the satellites are ~20'000 Km away, a rover-base distance < 100 KM means that they both see identical distortions and this is why RTK baselines are generally recommended to be less than 50-100 Km.
If follows that it is perfectly acceptable to perform a Survey-In in 1 minute with an error of 5 metres, your accuracy will be no better than surveying for an hour with a 30cm error. That said, expect a survey-in of 1 metre to take about 10 minutes.
You can scroll in and out with the mouse-wheel, but the minimum is 1 metre. To scroll in more, hold the Shift key, whence you can scroll in to a diameter to 20 cm.
The default baud rate is 19'200. Initially, I couldn't get the RTCM messages to flow and finally discovered an error message: "GNTXT More than 100 frame errors, UART RX was disabled". Reducing the baud rate to 9'600 fixed this, with no apparent consequences.
What does all this mean in layman's terms?
On average, you will get one reading worse than these values every 6 minutes.
Precision. Will never be worse than the precision of your base station ±356 mm (the radius of the 24-hour CEP).
The promised accuracy is indeed 'stunning'.
When combined with a TOF camera, the accuracy of a few centimetres is more than adequate for the mower I am building, so I'm perfectly satisfied with it.
That said, the limitations I discovered preclude this solution in some other use-cases that come to mind. Both UAV and farming applications require a much longer baseline and the inability to maintain Fixed mode accuracy is a handicap for those needing consistent high accuracy.
If UBlox can fix the baseline limitation and significantly improve the unit's ability to stay in Fixed mode, this GPS will become a truly amazing feat of engineering.
In the spirit of openness, you are welcome to use the data that gathered, for whatever purpose you see fit. Download here.
I am indebted to my local surveyors, JC Wasser, for explaining the finer points of their art and their advice on how to present my results.
If you'd like to try this solution, here's a summary of the user guide, along with a few tips.
Download the latest firmware. When you install it (Tools-Firmware Update), it'll ask for the FIS file which nobody talks about; it's is hidden away in the u-centre program files, called flash.xml.
The base station needs power. It'll take if from USB but you're going to need a source of external power once you've finished configuring it. It needs to be between 3.7 and 20 VDC, the + and – signs are on each side of the power connector, you'll need a magnifying glass to read them.
Fire up u-centre and connect the card you've chosen as base station to a USB port (the cards are identical, it's your parameters that make them base or rover). Don't try connecting more than one station to your PC at the same time!
In what follows, you need to click 'Send' in the toolbar at the bottom to transmit you settings over USB to the base station.
In Message view-UBX-CFG-GNSS, make sure GPS and GLOSSNAS are enabled.
The base station also needs to know its own location, which it can figure out itself. Expand UBX-CFG-TMODE3, select Mode=1-Survey-In; this is what makes it a base station. The Maximum Observation Time and Required Position Accuracy are actually quite unimportant, because it doesn't matter what the true latitude and longitude are, so 300 seconds and 3 metres are fine. Assuming you've got a good sky view it'll finish the survey easily in the 5 minutes. If you really insist on better precision, it takes about 10 minutes for an RPA of 1 metre.
UBX-CFG-MSG and enable F5-05 RTCM3.2 1005, 1077, 1087 and 1230 for UART1. They should all be set to 1 Hz except 1230 where 10 seconds is enough for the GLOSSNAS Code-phase biases.
UBX-CFG –> PRT set the target=1-UART1, Protocol-in=none, Protocol-out=5-RTCM3 and the baud rate to 9'600. This is saying: Send all RTCM messages to UART1, where they'll get transmitted on the UHF radio link. I couldn't get the recommended 19'600 baud rate to work, I kept getting "GNTXT More than 100 frame errors, UART RX was disabled" messages.
UBX-CFG-CFG and save the configuration. That way, when you power-cycle the base, it will resume operation normally. If you forget this and lose power, go to step 2.
After a while, perhaps up to half an hour, in the Data View, you'll see the base station switch to TIME. If it doesn't, don't worry, it'll get there eventually and FLOAT mode already gives good results.
Unplug the base station and connect the other, rover, station.
UBX-CFG-PRT set the target=1-UART1, Protocol-in=5-RTCM3, Protocol-out=none and the baud rate to 9'600. This is saying: RTCM messages will coming in on UART1, the UHF radio link.
After a moment, the rover should start receiving RTCM messages. You won't see them by default, UBX-CFG-Messages right-click on RTCM and 'Enable child messages'. Then open the packet console to see them (you won't see anything in the Text Console).
Once they're flowing in, time for a beer, the rover has to converge on the solution and this can also take a while, for me 20 minutes at minimum. You can monitor the convergence progress with UBX-NAV-RELPOSNED, click the 'Poll' button bottom-left to update the display if it isn't enabled. The N and E Relative accuracies will fall gradually and eventually reach 0.01 = 10 centimetres.
After some time it should switch to Fixed mode. If it doesn't, don't worry, as I mentioned in Lessons Learned, Fixed mode is better but not a pre-requisite for decent results.
Now, and only now, can you make meaningful observations. Restart u-centre (the only way I found to reset the Deviation Map) and View-Deviation Map (F12). Yellow dots = last value, green dots = previous values. To zoom in closer than 1 metre, press Shift whilst scrolling the mouse wheel, the minimum is 20 centimetres.
Conditional formatting is a great tool, but after a spreadsheet has a lot of edits, the number of conditional rules spirals out of control.
It replicates the formatting column-by-column, copying the conditional formatting from the first (top-most) cell which has some. Make sure that the rules you want propagated are topmost in the list and include that topmost cell before running.
Corollary: It doesn't handle multi-column formatting.
' Open the workbook with conditional formatting.
To say that I'm impressed is a vast understatement.
This spreadsheet contains the VBA code to write an Excel range as a clean, formatted HTML page, with optional auto-refresh.
NOTE If you click on the 'This spreadsheet' link above and it opens a ZIP file or a set of HTML files, right-click on the link and choose Save As.
Correctly renders all Excel formatting, including conditional formats.
Generates an HTML page with tabs identical to those in the Excel file.
Creates clean, formatted HTML that validates to HTML 4.01 strict.
Optimised stylesheet to ensure minimal page weight.
Supports merged cells with ROWSPAN and COLSPAN.
Updates the webpage automatically when cells' values are changed.
The webpage automatically refreshes itself at a user-supplied interval.
The result is almost pixel-perfect, compare this Excel screenshot with the HTML page it generated.
14 March 2013. Update, improved lower tab bar to stop over-spilling (thanks to Paul Palmer) and added support for 64-bit Office.
Excel Menu->Insert->Chart and choose any chart type. This will insert an empty chart.
28 September 2014. Now handles Unicode text correctly.
17 December 2018. Now outputs hyperlinks correctly.
I though this would be trivial; turns out it's not.
When you copy a formula from the clipboard, relative references are adjusted, so Range(x).Formula=Range(y).Formula doesn't produce the expected results.
The correct way is Range(x).Formula=Range(y).FormulaR1C1. Easy once you've been there.
Copying border formats with Range(x).Borders=Range(y).Borders crashes Excel. You have to copy each individual border, left, right, top, etc.
Similarly for fonts, you have to copy the font attributes one by one.
Good practice: check that the areas have compatible sizes and don't overlap.
' Copy cells without using the clipboard.
' Source is a range from which to copy values/formulas/formats.
'     a single cell, the top-left of the target range. The source size (rows x columns) is copied.
'     a range exactly the same size as source. We throw an error if the shapes don't match.
' If 'what' is omitted, copies the values.
' what=CopyFormulas copies the formulas instead of the values.
' what=CopyFormats copies the formats.
For those who envisage building an Excel RTD server, I have written a tutorial and open-sourced the code on SourceForge.
I hope that you will find it useful.


text:
Q: Reputation in side-bar not matching profile I've noticed a delay in the reputation score updating in the sidebar of the iOS app, but viewing my profile through the app shows the correct reputation.
Below is the sidebar, note the score for StackOverflow:

And below is the profile for SO in the app, again note the score:

I had some upvotes and an answer a few mins before this, so seems to be some sort of delay in the process that updates the sidebar.

A: This will be fixed in the next build.
The reputation shown in the menu is part of the network user cache used throughout the app (mainly as a quick way of checking for site membership or checking if you own a post).
Other than reputation, we don't expect this to change very often without direct interaction on mobile.  Specifically, we only check for changes every 10 minutes and then we don't normally block on the update, instead showing the old values at that moment.
That said, opening the menu is (in your case) an explicit request to show reputation so it's a good time to reload that cache.  Now we will:

*

*Continue opening the menu in a non-blocking way displaying old values so it opens instantly.

*When opening, also reload the network users.  When they come in, update the reputation numbers.

This way things stay responsive and your rep stays up-to-date.

redpajama_set_name: RedPajamaStackExchange


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The application of wood ash from biofuel sources to the forest has been suggested as a source of nutrients for trees and for restoration of acidified soils and surface waters. Studies on the effects of wood ash on aquatic organisms and ecosystems are, however, few. This study investigated the effects of wood ash (0.1 - 10 g l-1) on the freshwater moss Fontinalis antipyretica Hedw., which has previously been shown to be a sensitive test organism for assessing environmental pollution. After nine weeks of treatment with wood ash, a significant effect of enhanced stem growth was observed at the higher concentrations (1 � 10 g l-1). The concentration of wood ash was also correlated to the growth of secondary branches. Photosynthesis (oxygen evolution after 4 h of exposure to wood ash) was significantly lower in the alkaline treatments (no pH adjustment) compared to the treatments with neutral wood ash solutions (pH adjusted to 7.5). Furthermore, photosynthesis in the alkaline wood ash treatments was significantly lower compared to the control. The ratio between the optical density value before and after acidification (OD665/665a) was higher for all wood ash concentrations compared to the control. The OD665/665a values ranged from 1.52 to 1.61 and there was a difference, however not significant, between the alkaline and the neutral treatment at 10 g l-1 wood ash. This study clearly demonstrated that wood ash may be beneficial for F. antipyretica at moderate concentrations (0.5 - 5 g l-1), particularly when sudden increase in pH is avoided.
Wood ash application (WAA) to the forest has been suggested as a resource of nutrients for trees and for restoration of acidified soils and surface waters. However, studies of the effects of WAA on aquatic systems are few. This study investigated the effects of wood ash (1-25 g L-1) on the unicellular flagellate Euglena gracilis, which has been proved to be a sensitive test organism for assessing environmental change. Long-term (7 days) growth studies and short-term (direct, 24 and 48 h) studies of different motile factors, using the automatic biological test system Ecotox, were conducted. The results show no indication of biotoxic effects due to wood ash (adjusted to neutral) treatments. However, when no adjustments of pH in wood ash solutions were made, inhibitory effects on motile factors and cell growth were observed at higher concentrations of wood ash (10-25 g L-1) due to high pH (> 8). In tests with pH adjusted to neutral, enhanced motility was observed. These results indicate that high concentration of WAA could affect freshwater environments.
Wood ash application has been suggested as a means to mitigate acidification of surface waters. However little is known about the effects of wood ash to freshwater organisms. A Clark-type oxygen electrode was used to investigate the effects of wood ash, cadmium and aluminum on the respiration of the freshwater amphipod Gammarus pulex (L.). Harmful effects following wood ash addition were primarily found to be explained by elevated pH. At high concentrations (> 1 g/l) of wood ash the respiration of G. pulex decreased when no adjustment of pH was made, a response that was negatively correlated to the elevated pH (r = -0.43). An ion-related response was also detected in the pH-adjusted (pH 7) tests, although it was not statistically significant. Cadmium proved to be sublethal in the range of 0.2-0.4mg/l in a 24-h exposure. Mortality was 100% at 0.5 and 1.0mg Cd/l. No effects were detected after exposure to Al, due to the high pH (pH 7-8) of the solutions and the subsequently low concentrations of labile monomeric Al. We demonstrate that the method described in this paper could be a useful probe for the detection of sublethal concentrations of contaminants in freshwater ecosystems.
The dinoflagellates constitute a group within the protistan supergroup Alveolata, and can be referred neither to the plant nor the animal kingdom. They swim about using two flagella and are able to orient using various stimuli. About half the living dinoflagellate species are capable of oxygenic photosynthesis, but most of them complement this with capture of prey. Some live ebtirely by capturing small organisms, others are parasites. Some species are able to emit light. The group has a long evolutionary history, and almost as many extinct species as extant ones have been described. Most remarkable is the way the photosynthetically potent dinoflagellates have aquiered their chloroplasts by endosymbiosis with photosynthetic organisms from many different groups. In some cases repeated endosymbiontic events have taken place.
De flesta revbildande koraller lever i ett ömsesidigt beroende med så kallade zooxanteller, encelliga alger som lever inuti koralldjuret och som med hjälp av sin fotosyntes bidrar till försörjningen.
Institutionen för Fysiologisk Botanik, Lunds Universitet.
At fluence rates below 45 W· m-2 cells of the flagellate stage of Haematococcus lacustris react only positively phototactically with a rather high degree of orientation (indicated by r values up to 0.66 with the Rayleigh test). The directedness of orientation decreases with decreasing irradiance. The degree of directedness of the phototactic response depends on the intensity of preirradiation: Low light intensity applied after strong light application results in a dark reaction (low r values), low light given after darkness stimulates a rather high degree of directedness of positive phototaxis. Weak blue light ( =483 nm; 0.4 W · m-2) stimulates positive phototactic response, whereas comparable red light ( =658 nm; 0.5 W · m-2) does not.
Cells which were grown in a medium containing 10-4 M Norflurazon (effective in inhibition of carotenoid biosynthesis) although maintaining motility completely lose the ability to react positively phototactically. The possible role of carotenoids in the phototactic orientation is discussed.
Phototaxis is movement induced by light; this phenomenon has been detected in several solitary green algae species and generally works as a balancing force against gravitaxis, creating a system for optimum vertical placing in relation to irradiance, (energy -demands/restrictions). We study phototaxis in the mesophilic green algae, Chlamydomonas reinhardtii and C. raudensis SAG 49.72, relative to phototaxis in the from Antarctica newly isolated obligate psychrophilic strain of C. Raudensis (UWO 241) (henceforth called UWO 241). This species has some unusual movement patterns (Pocock et. al 2004) which function is yet to be revealed. Phototactic movement has not earlier been monitored in the normal conditions (high salinity, low temperature) for this strain, though when exposed to extreme temperatures (25C) the organism displays movement patterns interpreted as positive phototaxis. (Pocock et. al 2004). This behaviour should lead to a more rapid destruction of the organism due to the damaging high light (high energy input). The study shows that the three species responds different to light stimuli, when temperature is set to 12 C (culturing temperature) or the respective optimum culture temperatures. Light response curves of phototaxis in the range of 0,5 to 3000 μmol quanta m-2 s-1, shows that C. raudensis SAG 49.72 produce positive phototaxis over the entire range while C. reinhardtii mainly shows negative reactions. UWO 241 seem to be unaffected by irradiance, thus showing only nondirectional behaviour. In a second set of experiments the cells were kept in Petri dishes and exposed to 3000 μmol quanta m-2 s-1 under 40 min, in a temperature range of 5C to 25C for each sample. The results show that C. reinhardtii was negatively phototactic at 5C, switching to positive phototaxis at 25C.
The responses of the growth rate, motility, and cell shape in the green flagellate Euglena gracilis to different concentrations of waste water substances from the pulp and paper industry were tested in a long-term study (7 days). Samples before (uncleaned sample) and after (cleaned sample) the treatment in a cleaning system were studied. The influence of different doses of UV-B radiation on cell shape and motility was also investigated. No statistically significant effects of increasing concentrations of the waste substances both before and after the cleaning process (except inhibition by the undiluted uncleaned effluent) on the growth rate in E. gracilis were observed. Cell shape turned out to be an unreliable physiological parameter for assessing the toxicity at lower concentrations of waste water substances. No significant patterns could be observed in the response of the cell shape to the different concentrations of the waste water substances or to UV-B radiation. Motility has been concluded to be a more sensitive parameter than cell shape. However, no clear patterns were observed in the response of the motility to the different concentrations of the waste water substances studied. Increasing concentrations of the uncleaned sample demonstrated a defense against UV-B radiation, due to the high absorbance in the UV-B range, when effects on motility were examined. We conclude that contrary to the results reported in the literature earlier, cell shape and motility of E. gracilis are not universal physiological parameters for bioassessment at lower concentrations of toxic substances, including metals such as copper and zinc from the pulp and paper industry. The long-duration tests had, in general, higher significance than those of short duration.
Natural epiphyton and epilithon communities were studied in eu-, meso- and oligotrophic lakes at latitude of 62degrees54' N in Vasternorrlands region of Sweden. The samples of epiphyton as well as epilithon (three per lake) were identical and specific for each lake studied. Both epiphytic and epilithic communities consisted of members of three classes of algae - Cyanophyceae, Chlorophyceae and Bacillariophyceae. The highest species diversity was detected within Chlorophyceae while Cyanophyceae and Bacillariophyceae contained the same amount of species. In general, epiphyton and epilithon shared 44% of species identified. However, both epiphyton and epilithon showed distinct patterns between lakes of different trophic level. Epiphyton in the eutrophic lakes were clearly dominated by Cyanophyceae (Bacillariophyceae co-dominated in one of the eutrophic lakes). Both mesotrophic and oligotrophic lakes were signed by high abundance of Chlorophyceae and almost complete absence of Bacillariophyceae and Cyanophyceae. Epilithic communities in the oligotrophic lakes had higher species diversity than those in the meso- and eutrophic lakes studied. Chlorophyceae were dominant in two eutrophic lakes and Cyanophyceae only in one eutrophic lake, Chlorophyceae as well as Bacillariophyceae were abundant in the oligotrophic lakes. Cluster analysis based on species presence-absence led to a sufficient resolution between both epiphytic and epilithic communities of eutrophic environments, on the one hand, and epiphytic and epilithic communities of meso- and oligotrophic environments, on the other.
Phytoplankton communities at different depths and at different locations within each lake were studied during the period of ice cover (from January to March) in two eutrophic and two oligotrophic lakes in North-Eastern Sweden. Cryptophyceae, Dinophyceae and Euglenophyceae were dominant during the whole period of investigation in eutrophic environments. Bacillariophyceae, Chlorophyceae, Chrysophyceae and Cyanophyceae were only occasionally found both in eutrophic and oligotrophic lakes. Both in eutrophic and oligotrophic lakes diversity as well as abundance of phytoplankton were considerably higher immediately under ice than near the bottom. No differences in horizontal distribution of phytoplankton assemblages were detected within each lake. However, vertical differences were more profound. It is speculated that both light availability and increased ion concentration under the ice cover can be viewed as main factors determining phytoplankton communities.
Phytoplankton assemblages were studied during autumn 1998 in oligo-, meso- and eutrophic lakes in central Sweden (62°54'N). Differences in phytoplankton assemblages have been detected both in space and time. In eutrophic lakes coccoid Chlorophyceae dominated quantitatively during September and October. Diatoms were the most diverse group in all types of lakes in September and in meso- and oligotrophic lakes in October. In November Cryptophyceae became the most abundant group in all lakes. The total richness of species decreased in the meso- and oligotrophic environments in November compared to September and October, whilst in the eutrophic environment it remained almost unchanged. Cluster analyses, using both presence-absence and presence-absence in combination with abundance matrices, showed similar results and a good resolution between the lakes of different eutrophication conditions. We conclude that the phytoplankton assemblages of the lakes studied depended on the trophic conditions and thus they can be used for resolution between different eutrophication levels.
The simultaneous behaviour of seven ecological indices (Hurlbert's, Margalef's, Menhinick's, Shannon's, species number, Jaccard's and saprobic index) was studied based on phytoplankton data close to the shore on the East coast of Sweden during the summer 1998. The sampling stations had a similar eutrophication level and were located in bays. Standard phytoplankton databases were used in calculating the indices, which were later compared using cluster analysis. Hurlbert's, Margalef's, Menhinick's, Shannon's and species number indices, as measure of community diversity, produced similar trends which often differed from those based on Jaccard's index of similarity. However, the simultaneous use of these indices was found meaningful as a possible part of the monitoring close to the shore. The application of a saprobic index lead to erroneous conclusions in the studied case.
Usefulness of three types of artificial substrata (glass, wood and plastic) was tested when studying settlement patterns of periphyton in lakes of different trophic status. Strictly eu-, meso- and oligotrophic lakes in central Sweden were chosen as objects of the study. Glass slides, glass tubes, pieces of plastic (PVC) and pieces of wood of similar dimensions were placed for 9 weeks in July-August vertically 3 cm above bottom at a total depth of ca. 30 cm. Substrata were located at well-illuminated places without any other submerged objects (like macrophytes and stones), which could potentially affect colonisation patterns by algae. Periphyton communities, which colonised both the glass tubes and the pieces of wood tested, were specific enough to enable a clear classification of the lakes studied in eu-, meso- and oligotrophic. Glass tubes turned out to be the most favourable substratum when investigating settlement patterns of periphyton in this study. Although also colonised by periphytic species, wood did not support the same diversity and abundance of species as glass did. No algae were detected on the plastics studied. The plastics were covered entirely by a slime layer of bacteria. It is discussed if the nature of plastics could have some inhibitory effects on algal growth or the slime layer itself may have prevented settlement of algal spores.
The green flagellate Euglena gracilis was treated for seven days with concentrations of copper ranging from 0.02 mg L-1 to 2.0 mg L-1. No inhibiting effects were detected in any physiological parameters measured. In general, it seems that enhanced copper concentrations stimulated photosynthetic efficiency (PE) of E. gracilis. Concentrations of copper reported to be critical for the other algae studied (from 0.10 mg L-1 to 0.14 mg L-1) did not show any severe negative effects on E. gracilis. An unusual trend was observed where an increase in PE was followed by an increase in light irradiance necessary to achieve light compensation point. High capacity of E. gracilis to adapt to copper stress is being discussed as a possible explanation for the trends detected.
Background: Heavy metals, especially copper, nickel, lead and zinc, have adverse effects on terrestrial and in aquatic environments. However, their impact can vary depending on the nature of organisms. Taking into account the ability of heavy metals to accumulate in sediments, extended knowledge of their effects on aquatic biota is needed. In this context the use of model organisms (often unicellular), which allows for rapid assessment of pollutants in freshwater, can be of advantage. Pentachlorophenol has been extensively used for decades as a bleaching agent by pulpand paper industry. Pentachlorophenol tends to accumulate in the nature. We aim to determine if photosynthesis and motility can be used as sensitive physiological parameters in toxicological studies of Chlamydomonas reinhardtii, a motile green unicellular alga. It is discussed if photosynthesis and motility can be used as sensitive physiological parameters in toxicological studies. Results: The concentrations studied ranged from 0.1 to 2.0 mg l-1 for copper, nickel, lead and zinc, and from 0.1 to 10.0 mg l-1 for pentachlorophenol. Exposure time was set to 24 h. Copper and pentachlorophenol turned out to be especially toxic for photosynthetic efficiency (PE) in C. reinhardtii. Conclusion: Copper and pentachlorophenol turned out to be especially toxic for PE in C. reinhardtii. Zinc has been concluded to be moderately toxic while nickel and lead had stimulatory effects on the PE. Because of high variance, motility was not considered a reliable physiological parameter when assessing toxicity of the substances using C. reinhardtii. © 2001 Danilov and Ekelund, licensee BioMed Central Ltd.
Epilithic communities from brackish coastal water of the east coast of Sweden were studied in order to reveal their responses to different levels of UV-B radiation. The experiment was conducted for seven days in an indoor microcosm system. The epilithic communities were exposed daily to different doses of UV-B radiation: 1, 3, 5 and 7 hours, respectively. The intensity of the UV-B radiation used was similar to that in natural environments. After seven days clear shifts both in species composition and community structure were observed. All species of diatoms showed negative correlation with enhanced levels of UV-B. On the other hand, abundance of cyanobacteria was positively correlated with enhanced levels of UV-B (Calothrix aeruginea, R=0.49;Oscillatoria amphibia, R=0.93; Pseudanabaena mucicola, R=0.26). Communities dominated by diatoms and green algae at the initial stage of the experiment did show a drastic decrease in diatom abundance under UV-B stress and finally became dominated by cyanobacteria. Among green algae the abundance of Cladophora sericea correlated positively (R=0.33) with enhanced exposure to UV-B, while Monoraphidium-species exhibited negative correlation to UV-B. Otherwise, no significant correlation between other green algae species identified and UV-B stress could be detected. We conclude that UV-B radiation, even at lower levels, is capable to induce severe changes to marine epilithic communities. The trends revealed in the present study predict a shift from communities dominated by diatoms and green algae to those dominated by cyanobacteria.
Effects of increasing doses of UV-B radiation on photosynthetic efficiency (PE) and motility inChlamydomonas reinhardtii were investigated. The exposure time ranged from 10 to 120 min at 0.73 W/m2 UV-B radiation. A decrease in compensation points (CP) was followed by an increase in PE on extending the UV-B treatment up to 60 min. The subsequent increase in PE was accompanied by increasing CPs. Enhanced doses of UV-B radiation thus have a stimulatory effect on the PE inC. reinhardtii. No inhibitory effects could be detected. No statistically significant differences in motility could be observed due to an extremely high variation of values.
The influence of pH 3-10 on the growth, motility and photosynthesis in Euglena gracilis was demonstrated during a 7-d cultivation. The cells did not survive at pH <4 and >8, highest growth rate being detected at pH 7. Motility followed a similar pattern as growth rate. Photosynthetic response curves were shown to be of the same type over the whole pH range. High respiration was characteristic for cells grown at pH 5 and 6, the lowest one at 7. At high and also at low pH more active respiration was found which can be considered as a protective response on proton stress. Respiration was not completely inhibited with potassium cyanide. Photosynthesis was the most effective at pH 6; lower and higher pH decreased photosynthetic efficiency. pH affected more the growth rate than the photosynthesis.
Effects of short-term (1 h exposure) and long-term (7 d exposure) aluminium stress on photosynthesis and reproductive capacity have been studied in Euglena gracilis strain Z. Following concentrations of Altot (added as AlCl3) were tested: 0.5 mg L-1, 1.0 mg L-1, 1.5 mg L-1, 2.5 mg L-1, 7.5 mg L-1, 10.0 mg L-1, and 15.0 mg L-1 Al, respectively. Growth rates at different aluminium concentrations did not show significant differences, except at 15.0 mg L-1 Al. Initial respiration was higher in long-term than in the short-term experiments. It is supposed that an energy-dependent mechanism of excretion of aluminium ions has been active in the stressed cells. Consequently, the cells of E. gracilis after long-term exposure to aluminium are believed to be more acclimatised to the aluminium stress. Photosynthetic efficiency (PE) has been negatively affected by aluminium in all experiments performed. Differences between control algae and those treated with aluminium were significant in all cases. PE in long-term experiments was in general significantly higher at all concentrations of aluminium studied, compared to the short-term experiments. The aluminium concentrations tested led only to a general decrease in PE while the level of decrease was not especially concentration-dependent. In general, aluminium tolerance of E. gracilis can be estimated as low, especially by short-term exposure. However, good acclimatisation capacity of this green flagellate to aluminium doses by long-term exposure can be supposed.
Euglena gracilis and Chlamydomonas reinhardtii were used as model organisms to establish the best conditions for studying photosynthetic efficiency using the Light Pipetteexperimental system, which enables sensitive detection of changes in oxygen evolution/consumption and an easy collection and digitalisation of data. Chlorophyll concentrations of 0.005, 0.025, 0.050 and 0.075 mg mL-1 were investigated using different light regimes. Cultures of E. gracilis at the same chlorophyll concentration absorbed more light (measured at 580 μmol m-2 s-1) than those of C. reinhardtii. Cell density had a considerable effect on the reliability of measurements. Chlorophyll concentrations between 0.025 mg(Chl) ml-1 and 0.050 mg(Chl) ml-1 can be recommended when applying the Light Pipette system in bioassays using microalgae.
The green flagellate Euglena gracilis has been used as a model organism to elucidate the possible large-scale and short-term effects of waste substances from the pulp and paper industry on photosynthetic efficiency (PE). Different concentrations of waste substances before and after treatment in a cleaning system were studied. The uncleaned sample at concentrations up to 1:10 and the cleaned sample at concentrations up to 1:5 showed stimulating effects on the PE after 7 days of incubation compared to the control. The effects of waste substances on the PE of E. gracilis were also studied in combination with short-term studies (20 and 40 min) of ultraviolet-B radiation (UV-B, 280–320 nm). It was shown that increasing concentrations of the uncleaned sample had continuously stimulating effects on the PE and worked protectively against UV-B radiation. The cleaned sample exhibited no effects, or negative effects, on the PE of E. gracilis together with UV-B radiation compared to the experiments with only UV-B radiation. At the concentration 1:1 of the cleaned sample an increase in the PE was detected due to the high concentration of the coloured substances and a decrease in the UV-B penetration. PE revealed itself to be highly sensitive for detecting toxic effects on E. gracilis and is thus very promising for use in regular toxicity tests of waste water from pulp and paper industry.
Euglena gracilis was exposed for 24 hr to concentrations of copper, nickel, lead and zinc ranging from 0.1 to 2.0 mg L-1 and to pentachlorophenol ranging from 0.1 to 10.0 mg L-1. Photosynthetic efficiency (PE) was inhibited by increasing concentrations of the heavy metals. Nickel was found to be the least toxic of the metals to E. gracilis, while the other three metals exhibited similar levels of toxicity. Treatment with pentachlorophenol caused unusual responses of the photosynthetic apparatus probably due to the especially high toxicity of this substance. Both cell shape and motility turned out to be insensitive physiological parameters for the toxicity testing of the substances studied.
Three brackish water bays between Härnösand and Sundsvall on the East coast of Sweden (Gulf of Bothnia) were investigated between June and August 1998 in order to reveal summer phytoplankton dynamics close to the coast. All samples were collected at depth of 0,5 m. The results obtained show patterns in phytoplankton dynamics. In the spring Bacillariophyceae dominated, followed by an increase in Dinophyceae and small flagellates of Prasinophyceae and Cryptophyceae. Chlorophyceae were represented during the whole period of investigation especially with species of Monoraphidium, which often dominated or subdominated. In total 84 phytoplankton species were identified. Cluster analyses based on similarities in species' diversity and their abundance made it easy to distinguish between the bays close to Härnösand and the Bay of Sundsvall. However, no clear differences were found between the sampling stations within the Bay of Sundsvall.
Eutrophication was monitored with the aid of one similarity and seven diversity indices in the lakes of different trophic levels (eutrophic, mesotrophic and oligotrophic) in central Sweden. The ecological indices were applied separately to epiphyton and epilithon communities. Epiphyton turned out to be inappropriate for assessing eutrophication in the lakes studied. On the other hand, Hurlbert's, Simpson's and the similarity indices turned out to be promising environmental tools when applied to the data of epilithon.
The use of short-term tests with E. gracilis Klebs in order to assess toxicity cannot be viewed as absolutely preferable.At least in the case with wastewater from the pulp and paper industry, 7 day-tests could lead to more explanatory and significantresults.
The effects of ultraviolet radiation (UV-A, 315-400 nm plus UV-B, 280-315 nm) on photosynthesis and 'light-enhanced dark respiration' (LEDR) in Euglena gracilis have been investigated by using light pulses (80 s) with increasing photon fluence rates of 59, 163, 600, 1180, 2080 and 3340 mu mol m(-2) s(-1) and dark periods between the light pulses. LEDR is estimated as the maximum rate of oxygen consumption after a period of Light minus the rate of oxygen consumption 30 s after the maximum rate. Without any exposure to UV radiation, the photosynthetic rate and LEDR increase with increasing photon fluence rate. After 20 and 40 min exposures to UV radiation, the photosynthetic rate and LEDR as functions of photon fluence rate are reduced. After a 20 min UV treatment respiration is greater than photosynthesis after the first light pulse of 59 mu mol m(-2) s(-1) radiation, and especially at higher photon fluence rates photosynthesis is lower than the control values. The inhibitory effects of UV radiation on photosynthetic rate and LEDR are greater after a 40 min UV exposure than after a 20 min exposure. Only at 600 mu mol m(-2) s(-1) is the rate of oxygen evolution greater than that of oxygen consumption after a 40 min UV treatment. Both photosynthetic rate and LEDR are inhibited by the photosynthetic inhibitor DCMU (10(-5) M) in a similar way, which indicates close regulatory interactions between photosynthesis and LEDR. Potassium cyanide (KCN) inhibits dark respiration more than it inhibits LEDR. Dark respiration is not affected to the same degree by UV radiation as are photosynthesis and LEDR.
Department of Plant Physiology, University of Lund.
The effects of the calcium channel blockers, verapamil, diltiazem and lanthanum ions and the Ca2+ dependency on motility as well as the photophobic response (stop-response) of Gyrodinium dorsum were studied. At Ca2+ concentrations below 10-3 M, motility was inhibited. La3+ inhibits the stop-response, in contrast to verapamil and diltiazem. The only calcium channel blocker that increased the amount of non-motile cells was verapamil. The results indicate that motility are Ca2+ dependent and that the stop-responses of G. dorsum could be affected by extracellular Ca2+. Effects of the photosythesis inhibitor (DCMU) on the stop-response was also determined. With background light of different wavelength (614, 658 and 686 nm) the stop-response increased. DCMU inhibited this effect of background light. Negative results with the monoclonal antibody Pea-25 directed to phytochrome and the results with DCMU, indicate that the stop-response of G. dorsum is coupled to photosynthesis rather than to a phytochrome-like pigment. Oxygen evolution, but not cell movement, was completely inhibited by 10-6 M DCMU.
Irradiation of the flagellate Euglena gracilis by UV-B radiation resulted in inhibition of photosynthesis and motility. After 2 h of UV-B radiation (1.2 W m super(-2)) the rates of photosynthesis did not completely recover until after 24 h in visible light. After 24 h in darkness the rate of photosynthesis was lower but the recovery time in darkness after UV-B radiation was about the same as in the visible light. In the presence of lincomycin, inhibitor of chloroplast protein synthesis, therecovery of photoinhibition was totally blocked for up to 16 h recovery in visible light. However, after 24 h recovery in visible light together with lincomycin, photosynthesis was partially recovered but recovery in darkness together with lincomycindid not give any reparation at all of photosynthesis. The inhibition of motility had a slower recovery phase and had not fully recovered even after 72 h in visible light.
Dept of Plant Physiology, Lund Univ..
A depletion of the stratospheric ozone layer would result in an increased UV-B radiation, which could have harmful effects on marine organisms. The aim of this study was to determine the effects of an enhanced UV-B radiation (280–320 nin) on the motility and growth in four Swedish phytoplanklon species. The different plankton species were exposed to different doses of UV-B radiation during growth. The growth of the motile dinoflagellates, Gyronidium aureolum Hulburt (Ba 6), and Prorocentrum minimum (Pav.) P. Schiller (Ba 12), was more sensitive to UV-B radiation than the non-motile diatoms Dityhim brightwellii (P. West) Grun (Ba 15) and Phaeodactylum tricornutum Bohlin (Ba 16). One week of UV-B radiation 2 h daily (159 J m−2 day−1), had a dramatic effect on the growth of the dinoflagellates, while the diatoms were nearly unaffected. On the other hand, when given higher intensity of UV-B radiation (312, 468 and 624 J m−2 day−1) during the initial phase of growth, also the growth of the diatom, D. brightwellii, was inhibited. Not only the growth but also the swimming speed of the dinoflagellates C. aureolum and P. minimum were affected by UV-B radiation. The speed decreased rapidly after 1–2 h of UV-B radiation (312 J m−2 day−1), and after longer irradiation times the dinoflagellates lost their motility. G. aureolum exposed to UV-B radiation, regained normal speed after two weeks of visible light.
Experiments were performed to determine the effects of UV-B (ultraviolet, 280–320 nm) radiation on motility and growth of phytoplankton from lakes and ponds in South Georgia. After 4 h of solar radiation and 4h artificial radiation (UV-BBE 11.6 kJ m-2 day-1, UV-B lamps) the swimming velocity of Cryptomonas sp. decreased. The growth rate of Botryococcus, Lyngbya sp. and Stauraslrum sp. did not show any significant variations between the different light conditions. The UV-B component was reduced by filtering solar radiation through glass bottles und cellulose acetate. Cloudy days had only 30% of the radiation of clear days in both the PAR (photosynthetic active radiation) and UV-B regions. The ponds contained large amounts of humic substances, which are responsible for the absorbance in the UV region.
The effects of ultraviolet-B radiation (UV-B, 250–315 nm) were determined on Euglena gracilis with respect to speed, phototactic orientation, specific growth rate, and in the presence of humic substances. Humic substances had a protective effect when studying the speed and specific growth rate. However, the degree of phototactic orientation decreased in UV-B radiation both with and without humic substances. The inhibition of O2 evolution and speed was most pronounced when using cutoff filters WG280 and WG295. The photosynthetic inhibitor DCMU (10–6 M) did not have any effect on the speed, but the 02 evolution decreased to zero. The effect of different wavelengths in the UV-B region on the speed of E.gracilis showed the maximum sensitivity at 280 and 290 nm.


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22.4 The Senate House or Curia Julia
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Rome Redux: The Tetrarchic Renaissance
Except for the Aurelian Walls, Rome's third century was an "architectural wasteland." Diocletian created a new form of government called the Tetrarchy (four-man rule) with leaders in East and West. Public and private building campaigns in Rome and the provinces reflected the Empire's renewed stability and centered on enhancing or restoring buildings in the Roman Forum and constructing the Baths of Diocletian in Rome and Diocletian's Palace at Split.
22.1 Crisis in the Third Century and the Aurelian Walls 11:48
22.2 The Rise of the Tetrarchy 6:36
22.3 The Decennial or Five-Column Monument in the Roman Forum 10:28
22.4 The Senate House or Curia Julia 9:11
22.5 The Baths of Diocletian 9:58
22.6 The Palace of Diocletian at Split 9:41
22.7 Tetrarchic Palaces Around the Empire 16:13
Diana E.E. Kleiner
Dunham Professor of History of Art and Classics at Yale University
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Another building that Diocletian was interested in, in the Roman Forum, in terms of associating himself with Caesar and also with Augustus, was the Senate House. The Curia Julia it is called, the Curia Julia, because it was actually not built In the Diocletianic period, but built initially, begun by Caesar, begun by Julius Caesar to provide Rome with a Senate House in the Roman Forum. Begun by Caesar and completed by Augustus, after Caesar's death. But the building was, and that's why it's named Curia Julia, after the Julian family that, that Caesar, and also Augustus were a part of. But that building, the Curia Julia was destroyed, very seriously destroyed, in a fire in Rome in 283 A.D., and so what Diocletian does is he restores it between 284. He begins already in 284, well before the formation of the Tetrarchy, and he completes it in 305 A.D.. This restoration continues to be called the Curia Julia, but it at this point a Diocletianic building, but one that clearly to, where he instructed his designers to try to keep it as close to the original as possible. Now what you're looking at here on the right hand side of the screen is a coin, that comes from the period of the emperor Augustus, and it purports to represent. I don't think there's any question that it represents, given it's inscription and so on, the Senate House in Rome, as it would have looked as completed by Augustus, and he's in fact celebrating the completion of this monument. And associating himself through this coin with his divine adoptive father, Julius Caesar. If we look at the form, if we look at the, the exterior of this monument as it is depicted on the coin. You will see that it is a regular square, the front of the building is, is, it looks like a square with a very large pediment at the top, although I think that was accentuated here, its size. In order to allow the die cutter to include the sculpture in the pediment, and also the sculpture decorating the eves. We see the doorway, right here. We see there seem to be a triple window up above the doorway. And if you look very carefully, you will see that there seems to be a portico, a series of columns, that are there to relieve the severity of the otherwise very geometrically ordered facade. So that's what we, that's, what we think it looked like in the time of Caesar based on that coin. You see it over here in plan. This is a plan of, of the Forum in Rome, in the Augustan period,10 A.D., we see the buildings that were there at that time. The basilicas, the Temple of Divine Julius Caesar; the Rostra, but of course, without the Five Column Monument. No Arches of Septimius Severus. But we do see the Curia. And you see it here in plan, as a very plain, open, rectangular box, in a sense. So even in its Caesarian and Augustan beginnings, it seems to have been a very straightforward, straightforward, matter-of-fact kind of a building. This is a restored view of what we believe it looked like after the restoration by Diocletian. You won't be surprised to hear that the materials were different. That it's a building when in it's restored version it was made out of concrete faced with brick, exposed brick. So very much a building of it's own time. It would not have looked like that in the time of Caesar and Augustus. But they have, in every other way, they have kept to the underlying geometry of the form, to the use of the triple window with the curved top, as you can see here an arcuated top, a pediment up above. We don't know whether the second version had pedimental sculpture in it, or other decorative sculpture. The doorway down below. But the severity of the brick-faced, the exposed brick facade has been alleviated somewhat by the placement of marble revetment at the bottom part of the wall, behind a series of columns. So they have kept that portico, that set of columns, to relieve the severity, but also to make this building look as much as they could like the original Caesarian and Augustan structure. This is what the Curia looks like today. It is extremely well preserved as you can see. Yes, it's lacking it's, it's lacking its marble revetment, and it's lacking its portico. But in every other way, you can see very well, exactly what this building looked like in the time of Diocletian. Concrete faced with brick, with the very simple windows, and this very geometric abstract ordering, which again, I, I believe, you know, I think the explanation for that is two fold. One, that they are trying to maintain the look of the original Julian building, but also because this is again the aesthetic of the time. This decision to make buildings in, in a very geometrically ordered obstruct way, I believe again to reflect the stability of their new government. This building, the Curia Julia, owes it excellent, excellent condition to the fact that it, like so many buildings we've talked about this semester, was reused over time. We know that it was turned into a church already in the seventh century B.C.. That it was restored in the twelfth and in the sixteenth century A.D.. Did I say seventh century B.C.? If I did, I meant A.D., seventh century A.D., twelfth and sixteenth centuries and then again in the seventeenth century. And it was in the seventeenth century, that it, like so many other Roman structures, was transformed into a Baroque church, by an architect by the name of Martino Longhi the Younger. I put his name on the monument list for you. Martino Longhi the younger, and it was re-consecrated as San'Adriano, Saint Hadrian, al Foro Romano, San'Adriano al Foro Romano, Saint Hadrian in the Roman Forum was the church. And when I say Baroque church, I mean a Baroque church. It was deconsecrated by Mussolini in the 1930s, Mussolini returning it to its original ancient form, as you can see over here. But this photograph, shows the work that was being done in the thirties to dismantle this baroque church into which the Curia had become, I mean its really hard to believe that this was the Curia in the seventeenth century. But that's exactly what it looked like as well as in the early twentieth century. And you can see a bell tower had been added, buttresses had been added to this structure, completely encasing the Curia in a Baroque church. And we see that being dismantled in this view over here. And I have a view I can show you also of the interior. This was the interior in the seventeenth century. Impossible to, to see that original box, simple box like interior that was there in the time Diocletian, and probably there in the time of Caesar and Augustus. So filled is it with the usual Baroque paraphernalia of you know, elaborate stucco work and Angels flying through the skies and these, these, you know, not that we haven't seen this kind of thing in Roman architecture. We, of course, have, but you can see that the original shape of this particular building has been completely disguised by Martino Longhi the Younger as he redoes the Curia as a Baroque church. This is what, when they took all of that baroque accretion off this is what they ended up with. This is what the Curia looked like, probably, very similar to this in the time of Caesar and Augustus. What it looked like under Diocletian and what it again looks like today. You can see from this, from this view this very simple box like shape for the interior of this structure. Plain walls, coffered, a flat coffered ceiling. The only the only light brought in by a series of very simple windows with arcuated tops. Allowing light into the system and then down below. Again the brick facing, the concrete and the brick facing expose, but with the down below probably some marble revetment on the wall down here. Very simple niches arcuated in rectangular niches. But very, very simple ones. And then here you see the benches, the stone benches, on which the senators would have sat, when they were deliberating or stood in front of, because they got up a lot and orated. But stood in front of when they delivered their speeches or, or sat. And then down below, the original, the original marble revetted floor is still preserved. And I can show you two views here, in color, of that floor, to give you a sense all done in marbles. Marbles brought from different parts of the world, but the usual colors that the Romans liked for most of their marble. Pavements, or white or of off-white, maroon, green, and black, but very nicely done for this very simple, very geometrically ordered. But very beautiful interior.

redpajama_set_name: RedPajamaCommonCrawl


Enjoying a glass of wine is more than an epicurean delight, it is an art form. That is ... when glass itself is an art piece.
These beautifully handcrafted wine glasses from Antoni Barcelona are designed to perform, they are both light and solid to hold and last. The overture is wide enough so that you can immerse your olfactory senses in deep aromatic happiness and experience the total complexity of the wine before enjoying your first sip.
Inspired by the world-renowned satin glass arts of the Sagrada Familia Basilica in Barcelona.


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Registration open for SONNY's 2015 CarWash College
TAMARAC, Fla. — The schedule includes 33 percent more classes over the 2014 schedule.
TAMARAC, Fla. — SONNY's The CarWash Factory has posted its 2015 CarWash College training schedule, and registration is open, according to a press release.
Carwash operators can take part in courses in management, maintenance and repair, said the release. Thirty-three percent more courses have been added compared to last year.
A quarterly one-day New Investor Seminar will also be held for those interested in entering the carwash industry, noted the release.
Read also: Starting a carwash
Students will have access to a state-of-the-art laboratory containing equipment typically found at a carwash, reported the release.
Training programs are non-brand specific, and 95 percent of the material learned can be transferred to any type of conveyor carwash, stated the release. More than 30 percent of students own a brand other than what they were trained on.
"Since its inception, SONNY'S The CarWash Factory has had 2,350 CarWash College graduates," stated Robert Andre, president of CarWash College, in the release. "I have had the opportunity to meet some really amazing people and form long term relationships during the past eight years."
Click here to view the 2015 course schedule and for more information.
Tommy's Express Car Wash named No. 1 Smartest-Growing Franchise
HOLLAND, Mich. — The brand has its foot on the gas to open 60-120 carwashes per year.


Telschig Big Bag Systems are used worldwide. Our special technology guaranties complete emptying in 1-3 minutes per Big Bag. Manual support is not required with our Bulk Bag handling equipment. Execution mobile or stationary. Robust and automatic operation distinguishes our technology. The opening of one trip Super Sacks happens automatically trough a stationary circular knife without motor at the bottom. Multi trip Bulk Bags come with emptying valves which have to be opened manually. By dismantling the circular knife the bottom of the Big Bag remains undamaged.
During the rapid emptying of one trip Big Bags through an opening with diameter of 650 mm, the maximal emptying capacity is circa 25 Big Bags per hour. The effective output depends on the local infrastructure and logistics on site.
Successful application for all Bulk Bag designs and materials up to a content of 2 m3.
A small selection of application possibilities of our big bag emptying stations from previous projects and inquiries in the year 2018.
Find out more about our extensive range of services!


text:
Q: Problema con Python 3 (Salida inesperada para calcular el número más pequeño)
Este es un programa que hice siguiendo un tutorial, pero al probarlo me da una salida inesperada, ¿Cuál podría ser el error?
Éste es el texto:
x = input('Give me a first number: ')
y = input('Give me a second number: ')
z = input('Give me a third number: ')

print('')

if x < y and x < z:
    print(x, ' is least')
elif y < z:
    print(y, ' is least')
else:
    print(z, ' is least')

A: Al parecer es un error típico al momento de comparar  porque en realidad está comparando string es lo que retorna el input , para solucionar podría hacer el cast a un valor numérico como int.
x = int(input('Give me a first number: '))
y = int(input('Give me a second number: '))
z = int(input('Give me a third number: '))


text:
60-я годовщина Победы в Великой Отечественной войне — серия памятных монет Центрального банка Российской Федерации, посвящённых 60-летию Победы в Великой Отечественной войне 1941—1945.

История выпуска
В данной серии представлены монеты пяти различных монетных типов. В каждом представлена одна разновидность монет. Часть монет исполнена из драгоценных металлов — серебро, золото, часть из латуни и мельхиора. Тематикой серии стали события и участники войны.

В серии представлены:
 биметаллическая монета номиналом 10 рублей из недрагоценных сплавов;
 монета из серебра 925-й пробы номиналом 3 рубля;
 монета из серебра 925-й пробы номиналом 100 рублей;
 монета из золота 999-й пробы номиналом 50 рублей;
 монета из золота 999-й пробы номиналом 10 000 рублей.

О монетах

10 рублей
Чеканка монеты началась 11 января 2005 года, что не характерно для памятных монет, посвящённых событиям Великой Отечественной войны (обычно монеты чеканят перед 9 мая). Из-за большого тиража, монета редкой не является. Её можно встретить в обороте.

3 рубля
Трёхрублёвая монета из серебра 925 пробы была выпущена в количестве 35 000 штук. Это довольно крупный тираж для памятной монеты из серебра. Ориентировочная стоимость одной монеты на январь 2013 года — 1500 рублей. Эта цена ниже средней стоимости инвестиционной монеты — Георгий Победоносец из серебра 999 пробы и весом в тройскую унцию.

В 2005 году к 60-й годовщине Победы в Великой Отечественной войне 1941—1945 годов были выпущены наборы из трёхрублёвых монет для вручения в качестве подарков зарубежным гостям, прибывающим на праздник. На Московском монетном дворе было выпущено всего 1000 наборов.

В наборе 15 монет из серебра 925 пробы, каждая массой 31,1 г. На каждой из 15 монет методом цветной печати нанесён герб одной из 15 республик СССР.

100 рублей

50 рублей

10 000 рублей

См. также
 Памятная монета
 Список памятных монет России
 Структура каталожного номера монет России

Литература

Ссылки
 Сайт Банка России

Памятные монеты России
Юбилейные монеты России

redpajama_set_name: RedPajamaWikipedia


You don't need no stink'n base building, right? Wrong.
In today's episode, I discuss the importance of a base building cycle before your next training plan starts, and the 6 principles I follow to make sure it's worth my time.
Whether you're training for a half marathon, marathon, or ultramarathon, focusing on building your base mileage and endurance before race specific training is key to a successful and injury free race.


text:
Q: how to boot from ubuntu 12.04 CD I purchased a laptop which was pre installed with Ubuntu 13.10. With whole drive of 350 GB as a one partition (there is an extended swap partition of 2GB)
I want to install windows 7 with dual boot as well as make one partition for data.
How can I do this.??

*

*Gparted can not unmount the drive so I can repartition it.

*Live CD not booting so that I used Gparted through it. Why it is not booting? (By the way I'm trying ubuntu 12.04 CD as a live CD)

A: Speaking of boot, try to figure out which key is assigned by BIOS for getting you to the boot screen for your computer. It could be F12, or F9 or F10, just make sure you press the right key to be able to boot from CD/DVD.
As for deleting your old partitions, I suggest you use the  Ultimate Boot CD . It is a fine piece of work, and it is free. The iso image is around 600mb and it fits on a regular CD. Download it using the torrent link provided in there, burn it on a blank CD, and then reboot with your new Ultimate Boot CD in tray. At first boot screen you'll see a menu from which to choose (many, many useful tools in there for both Windows and Linux, including GParted).
What you need is to access the HDD - Partition Management section, and from there to select the "Cute Partition Manager" tool. Let it load al its modules, and when finished loading do not press BROWSE instead press OK. You should finally get to the partition table for your HDD device.
Delete all partitions in there, starting with that SWAP section, and moving to the other ones (if there are more than one left). To be able to delete partitions use the assigned keys listed at the bottom of the screen. Do not forget to save your empty partition table at the end (there is a key, I don't remember which one, for saving final partition table, press it and save your empty partition table). Exit Cute Partition Manager, take CD out of tray, and reboot, then power-off your PC. Your hard-disk should be fresh and cute like a baby now :) .
If you prefer GParted instead, then use that one, it is located in the same section: HDD - Partition Management.
You can install Win7, and make a dual boot with Ubuntu after that. Do not use Cute Partition Manager to repartition your hard-disk. I don't think Gparted is an option either if you want to install Windows and Linux in dual boot.
Better to use a bootable WIN-XP CD to partition your entire HDD (primary and extended partition). WIN7 DVD does not create extended partitions, only primary partitions, and I am sure you want to add extended partition (I suggest you create more than one logical drive inside the extended partition). Leave enough free space for a Linux installation, or even better create a raw logical drive inside the extended partition for your Linux system.
Please be aware that you will loose all your data from the hard-disk after deleting your old partitions. Use it at your own risk, don't blame me if you forget to back-up important data before using Ultimate Boot CD to wipe up your HDD.


This Parkside Plan 4 home features incredible views of the Ogden valley, Nordic ski resort and the valley floor. Parkside is a planned unit development with an HOA and is the only Eden single-family home development zoned for nightly rentals. This home offers quartz countertops, 11 ft vaulted ceiling in main living area and 9 ft walls. Additional upgrades include higher-end appliances, cabinetry and countertops, two large entertainment rooms on lower level with a walk-out basement and a hot tub vault on back patio. This home is located at the base of Powder Mountain Ski Resort and a short distance to miles of hiking and biking trails, Wolf Creek Resort, Pineview reservoir and much more for those outdoor enthusiasts. Purchase includes a one-year family membership to Wolf Creek Resort Golf and Fitness club.
Popular Sunpeak floor plan located near Wolf Creek golf course and Powder Mountain in the Ogden Valley. The Fairways community offers one of the most picturesque settings imaginable. Living at The Fairways provides easy access to year round recreation, including skiing, golfing, boating, hiking, biking, fishing & horseback riding. The Sunpeak floor plan offers a spacious open kitchen and gathering areas with 3 bedrooms and 2 bathrooms.


If you love the camp experience, sign up for Adventurers!
Adventurers Youth Camp is one of our many 5 night sleepaway camps. All campers are cared for by a cabin counselor throughout the week, have a support staff assigned to be with them overnight every night, rotate through activities in the days together and bond with their cabin mates. Cabins participate in every activity available including Canoeing, Archery, Rock Climbing, Low Ropes, Swimming, Crafts, Drama, an Overnighter, Field Games and others. As a whole camp every cabin spends time at morning singing, field games in the evening, curriculum skits in the afternoon, Chapel time in the evening and every meal.
Don't forget the unforgettable Squeah Skit Night on Thursday, Friday Wide Game and our Campers Choice activity! There's so much to be excited for, not least the great friends that the youth make with their cabin and counselor. While they're having fun, staff share their joy and friendship with God and we hope all campers will discover how absolutely amazing He is!
Camp Squeah is conveniently located in the Lower Mainland in Hope BC. Just a 2 hour scenic drive from Vancouver BC.


2026 42nd Ave, Longview, WA 98632 (MLS # 1435952) | Real Estate in Cowlitz County & Beyond!
Somebody's Little Darling. Everything Has Been Redone Inside and Out. Includes A WOW Factor Kitchen W/Quartz Countertops, SS Appliances, Soft Closed Cabinets, W/Lots of Storage. Lam Flooring Thru out, (carpet in 3rd BR). Dbl Sinks in BA, New Elect & Plumb, Windows, Siding, Paint and Wood Deck Porches In Front & Back. In the Back You Will Find A Repainted 6 Bay Detached Garage/Shop, Repainted Horse Barn & Pasture. Room For RV Parking and All Your Toys. All on A 66x634 Lot on A Dead End Street.


text:
The Israeli secret services (Eric Dénécé and David Elkaïm)
Aman, Shin Beth: These two names may not ring a bell, but they are, along with the much more well-known service Mossad, part of the Israeli intelligence community. Eric Denécé and David Elkaïm give us a account of the action of the Israeli intelligence services from the founding of the State of Israel to the present day.
What perspective?
Director of the French Intelligence Research Center (CF2R), Eric Denécé, former analyst, is one of the leading French specialists in the intelligence world. After having wondered about the history and the quality of the French intelligence services in "Are the French secret services null?" », He delivers, in collaboration with David Elkaïm, also a researcher at CF2R, a high quality work. If it seems difficult to work on archives of the Israeli services, the authors have filled these gaps by relying, on the one hand, on the press specializing in intelligence, as well as on the memoirs of former actors and former heads of Israeli services.
The distribution of tasks between the different departments
Intelligence is immediately presented as the "life insurance" of the Hebrew state. A small state with no strategic territorial depth in the event of a conflict, confronted from its creation with hostility from its neighbors, Israel quickly had to rely on intelligence in order to prevent and anticipate any conflict. The tasks were gradually divided between three main services: the Mossad is responsible for intelligence gathering in surrounding countries and clandestine operations, the Shin Beth is responsible for domestic intelligence, and Aman is responsible for military intelligence. Although very descriptive and sometimes tedious, the first part of the book recalls the history of structures and the role of each of the departments.
From the Six Day War to Iran's nuclear program: the many challenges facing Israeli intelligence
More than the simple anecdotes that can sometimes be found in books on espionage, Denécé and Elkaïm's book reflects all the issues of international politics since the 1950s. In the 1960s, intelligence was mainly concerned with intentions of the main Arab rivals - Syria and Egypt - and therefore endeavored to infiltrate the upper echelons of power: this is the case in particular of the spy Elie Cohen, who, pretending to be an Arab merchant, is inserted in the best political and military Syrians, even rubbing shoulders with Hafez al-Assad. The Palestinian question also occupies a significant part of the book. In this regard, it is necessary to underline the interest of an approach by the intelligence world, giving greater complexity to this question. The book looks in particular at the testimonies of former officers and directors of Israeli intelligence, gathered in the excellent documentary "The Gatekeeper".
The last part of the book deals with the confrontation of the Israeli services with Iran and its nuclear program. In addition to the targeted assassination of scientists and the sabotage of nuclear power plants, united under the name of "Plan Daniel", it is also an opportunity to address the issue of cyberespionage: the Israelis, at the forefront in this field, are notably at the origin of the computer worm Stuxnet, which they made in collaboration with the NSA.
Because of the many international issues and the situation of insecurity and uncertainties affecting Israel, this book constitutes an excellent introduction to the history of international relations in the Near and Middle East. He recalls both the efforts made by the Jewish state to ensure its security and the need to establish a dialogue with its neighbors. It also means knowing the intentions of other countries in the region, a task that falls to the Israeli intelligence community.
The Israeli Secret Service: Aman, Mossad and Shin Beth, by Eric Denécé, David Elkaïm. Tallandier, 2014.
Paradesi Synagogue and Jew Street, Kochi
Chauvet Cave Timeline
Greneda Geography - History
Copyright 2022 \ The Israeli secret services (Eric Dénécé and David Elkaïm)...


text:
WATCH: Up Close & Personal with Walk Off The Earth
Drummer Joel Cassady sits down with us to discuss everything Walk Off The Earth
Village Media Sep 12, 2022 2:59 PM
Join host Scott Sexsmith as he gets up close and personal with Walk Off The Earth's Joel Cassady.
From the early days of the band to touring and selecting songs and instruments, Cassady breaks it all down everything WOTE for us.
Watch the latest episodes of Up Close & Personal or subscribe and download wherever you find your favourite podcasts.
More Up Close & Personal
WATCH: Up Close & Personal: Year in review
WATCH: Up Close & Personal with Kelly Hrudey
WATCH: Up Close & Personal with Peter Mansbridge


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Yellen's message this week? Rate hikes are coming
Higher interest rates are coming.
That will be the message Fed Chairwoman Janet Yellen will try to send to markets this week, economists said.
"We expect Yellen to make it clear that the first rate hike is not far off," said Ian Shepherdson, chief economist at Pantheon Macroeconomics, in a note to clients.
Analysts think there is only a small chance the Fed moves at its next meeting, in July. Instead expectations have coalesced on the Fed's September move "unless something unusual happens," said Carl Tannenbaum, chief economist at Northern Trust.
Of course, Yellen will be more subtle than John Snow from the popular "Game of Thrones" television show, whose well-known catchphrase is "winter is coming."
"Those looking for some type of concrete message that September is effectively a done deal will likely be disappointed," said Michael Cloherty, head of U.S. rates strategy at RBC Capital Markets.
Yellen's message will be nuanced, asserting that rate hikes are coming as long as the economic data over the next three months performs as expected, said Michael Hanson, U.S. economist at Bank of America, Merrill Lynch. The Fed continues to believe the slowdown in the first quarter was transitory.
Economic data in recent weeks has shown a split between the strong labor market and weaker data like gross domestic product and the factory sector. Data on Monday put the manufacturing sector in a technical recession.
The Fed comes down on the side of the strong labor-market data, said James Glassman, economist at J.P. Morgan Chase.
"They think the economy is doing fine," and the majority on the Fed now favors starting rate hikes soon and going slowly, he said.
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CFDs are complex instruments and come with a high risk of losing money rapidly due to leverage. 63,41% of retail investor accounts lose money when trading CFDs with this provider. You should consider whether you understand how CFDs work, and whether you can afford to take the high risk of losing your money.


text:
« Evolution of the Universe Revealed in Computer Simulation Pesticides, Not Mites, Cause Honeybee Colony Collapse »
Polar Bears Evolved to Eat Fatty Foods Without Heart Harm
By April Reese | May 8, 2014 12:04 pm
Polar bears eat copious amounts of fat. Their diet consists mostly of plump seals, and fat accounts for as much as 50 percent of a bear's body weight. So why don't polar bears develop heart disease, the way humans who consume too much fat sometimes do?
The answer lies in the great white bear's unusual genes. In studying polar bear and brown bear genomes, Rasmus Nielsen of the University of California-Berkeley and colleagues discovered that polar bears diverged from brown bears about 400,000 years ago. As they adapted to surviving in an increasingly cold and harsh Arctic environment, genes associated with the cardiovascular system mutated in ways that allowed polar bears to eat massive amounts of lipids without developing heart disease.
Pinpointing when polar bears broke away from brown bears and blazed their own evolutionary path is key to understanding what drove the gene mutations and how fast large mammals like bears can adapt to extreme environments, the researchers note in the paper. Polar bears most likely evolved from brown bears after becoming isolated from other populations by a cooling climate.
What's more, they adapted especially quickly in evolutionary time: about 20,500 generations. The analysis, combined with recent fossil data, "provides us with an unprecedented timeframe for rapid evolution," the researchers write in the paper, published in today's edition of the journal Cell.
"Here you have two species that fundamentally differ in ecology, diet, and behavior, and they diverge in a relatively short amount of time," Nielsen says.
Emulating Polar Bears
So could humans eventually develop similar genetic workarounds, allowing us to eat lots of french fries and cheeseburgers without risking an early death from heart disease? It's possible, but those adaptations would likely take hundreds of thousands of years, Nielsen says.
"It's probably not worth waiting for," he jokes.
Still, the polar bear study and other genome analyses can tell us something important about the future of our own species, he says: "If you want to learn something about [human] health, looking at some of these organisms that have gone through these changes already is a useful tool."
Image by BMJ / Shutterstock
MORE ABOUT: animals, evolution


The number of migrants in the world surpassed 244 million in 2015, growing faster than the world's population. Nearly half of all migrants worldwide originate from Asia. Between 2000 and 2015, Asia added more migrants than any other major region, or a total of 26 million additional migrants. Most immigrants living in Asia, however, or 82% of the total, originated from another Asian country. This trend will not change anytime soon as structural factors driving international migration—demographic imbalances, economic inequalities, conflict, disasters, and the impacts of climate change—are likely to persist.
Well-managed migration, however, can contribute to sustainable economic growth and development in both countries of origin and destination. Evidence suggests that migration and remittances have an impact on income distribution, poverty reduction, and economic development. But none of this can be achieved without partnerships among important stakeholders: countries of origin and destination, the private sector, trade unions, and other civil society organizations.
At the same time, governments should not overlook the negative impacts of ill-managed labor migration: malpractice by private recruitment agencies, abuse and exploitation of migrant workers in host countries, brain drain in sending countries, and increasing irregular migration, including its worst form—smuggling and trafficking. Therefore, partnerships among stakeholders are crucial for effectively dealing with labor migration in Asia.
The eighth roundtable on labor migration organized by the ADB Institute (ADBI), the International Labour Organization (ILO), and the Organisation for Economic Co-operation and Development (OECD) will be hosted by the Human Resources Development Service of Korea (HRD Korea) on 30–31 January 2018 in Incheon, Republic of Korea. With the theme, "promoting partnerships for migration governance in Asia," the roundtable is significant because it will discuss lessons from Asian countries in building partnerships to effectively manage migration and contribute to achieving the UN Global Compact on for Safe, Orderly and Regular Migration.
Around 20 senior officials of agencies responsible for labor and/or migration policies from 10 developing countries in Asia (Bangladesh, the People's Republic of China, India, Indonesia, Malaysia, Pakistan, Philippines, Sri Lanka, Thailand, and Viet Nam), as well as international experts, representatives from multilateral banks, academia, and the private sector involved in labor and migration issues.
Participants are expected to attend and actively participate in all sessions.


If you value comfort and space, these are probably not the homes for you.
A team of students from the US and UK have designed tiny houses for 'affordable' living.
The 3D printed homes are intended to provide an alternative for young adults struggling to get on the property ladder.
The students from 3M future Lab, led by Professor and architect Peter Ebner, studied at the University of California and the University of Huddersfield.
University students in Atlanta announced the other day they have designed mini-houses for urban living.
'SCADpads' are 8 feet wide, 16 feet long and can fit in US parking spaces.
Each $40,000 abode can be individually tailored and decorated.
The team says half of America's 105 million parking spaces are empty.
And the 'housing crisis' could be solved by filling them with these homes.
The houses are entirely 3D-printed, providing a cheaper living solution than modern homes.
The houses are dome or mussel shaped and could be placed in various locations around the world.
Their portability and small size means that, in theory, they could be taken to places where regular houses could not be placed.
When closed, the top level of the home serves as a bed with the 'spring mattress', which is also 3D printed.
The closed structure is entered and exited via a small door located on the wall.
A projector is also included inside, allowing multimedia such as movies to be viewed inside the mini-home.
At the top a small eye-like window provides light inside the claustrophobic environment.
On the 'ground floor' is a movable kitchen countertop.
This also has a sink that covers a 'bathtub' of sorts.
A small kitchen can be extended that, apparently, is comfortable enough for two people.
There's even a fridge for you to store food and drink.
And Ebner tells MailOnline that the illustrations you can see here are accurate representations of how much space would be inside each of the prototype houses.
He stresses, however, that he will not be bringing the products to market - they are merely intended as an example to show what is possible.
The 'bathroom,' also found on the ground floor, has a folding toilet that is hidden in the wall when not in use. The house even has a shower as well.
The entire home is designed to be 3D printed, including the electricity, heating, water, sewage systems and thermal insulation.
'Returning to the 3D printing topic, it is necessary to underline that the apartment was printed on a highly detailed level,' the company said in a release.
However, according to the company, heater and water treatment devices are not able to be printed yet so non-3D printed replacements are used for now.
The hope is that the finished fully-3D printed homes could provide a solution for housing young adults around the world.
It is rumoured that a Chinese company is interested in manufacturing the product on a large scale to the order of hundreds.
Ebner says he is not involved in talks with them at the moment, but he would be involved 'for sure' if they got in touch.


Insurance can replace homes, furniture and automobiles in time of need. However, photographs, which are important pieces of a family's history, are unprotected. Operation Photo Rescue (OPR) is a volunteer network of professional photojournalists and amateur digital photographers, graphic designers, image restoration artists and others. OPR's mission is to repair photographs damaged by unforeseen circumstances such as house fires and natural disasters at no cost to the people who own them.


1. For the sauce, cut the tomatoes into rough cubes and set aside.
2. Heat the olive oil in a saucepan and fry the onion and garlic for 4-5 minutes, until softened.
3. Add the tomatoes to the pan, and bring to the boil. Stir in the oregano, reduce the heat and simmer for 15 minutes. Stir in the basil leaves and continue cooking for 15 further minutes.
3. Tip everything into a liquidiser and process until smooth - you could also puree everything with a stick blender. Strain through a sieve and leave on one side.
4. For the mozzarella, slice the mozzarella cheese into 4 slices about 1cm thick. Cut the crusts off the bread and stamp out, using a cutter, into discs slightly larger than the mozzarella slices.
5. Lightly beat the eggs and season with salt and pepper.
6. Dip one side of all the bread slices into milk. Put a mozzarella disc on top of the dry side of half the bread slices.
7. Season the mozzarella and make a sandwich with the other slice of bread, keeping the milk-soaked side on the outside.
8. Dust the 'sandwich' with flour, and coat in beaten egg.
9. Heat the oil in a deep-fat fryer and deep-fry the sandwich in a hot fryer until golden and crisp.
10. Drain the fried sandwiches on kitchen paper, and serve with the warm tomato sauce. Accompany with a heap of rocket leaves.