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  • Jim Jones added an answer in QR Codes:
    Is there anyway to apply QR code with GIS?

    I am working on a project which requires linking QR code with GIS in order for the system can query the information on certain spatial data.

    Jim Jones · University of Münster

    Well, I guess the easiest way to solve this would be to create a web service that provides information about each buoy. Once the user scans the QR code, it leads to the web service where the info is displayed. In case the buoy coordinates are not fixed, one can update them also using the scanning device during the information request. Depending on your storage technology (e.g. PostGIS, LOD) it will be straightforward to display it on a GIS.

  • Yuri Rzhanov added an answer in Morphing:
    Can someone help with identifying colors in images of one individual bird?

    The images of interest is of a individual Eleonora's falcon. This species comes in different color morphs. 

    1. Light morphs (Male: yellow-greenish color around eyes and at the naked skin above the beak, Female: has blue/grey color instead of yellow-greenish).

    2. Dark morphs  (Male: yellow-greenish color around eyes and at the naked skin above the beak, Female: has blue/grey color instead of yellow-greenish).

    3. Homozygous dark morph (Female: no yellow-greenish color around eyes and no yellow at the naked skin above the beak and complete black bill/mandible). 

    The plumage is dark so I could exclude "light morph", but it could either be a dark morph male or female, or it could be a homozygous dark morph (female). 

    See the different images of the same individual (except IMG_3165 and IMG_0575 is a image for comparison, this parental male has for sure yellow-greenish around the eyes and at the naked skin above the beak, and 2014-09-13 07-02-57 M 1_3.JPG, this parental female has for sure blue/grey color instead of yellow-greenish).

    To find the color morph of this one individual bird, is it possible to perform a analyze to identify if there is yellow-greenish around the eyes and at the naked skin above the beak? Similar, is it possible to identify if the bill/mandible is complete black? 

    Note for my question: In this case I only want to classify this individual bird on the images (newly edited this to make my question clearer). 

    Could the image lie, hence yellow at the image but not in the real world?

    For me it looks like there is some yellow-greenish around the eyes and at the naked skin above the beak (especially IMG_3155), although quite pale. If so it would be a dark morph male. 

    A reference paper about the color morphs could be found here:


    I'm not skilled in image analysis and I hope to get some help.



    Yuri Rzhanov · University of New Hampshire

    @Ronny. There is an extensive literature on the subject. See for example,  Thomas W. Pike, Using digital cameras to investigate animal colouration: estimating sensor sensitivity functions. Behav Ecol Sociobiol (2011) 65:849–858. DOI 10.1007/s00265-010-1097-7;

    Derya Akkaynak et al., Use of commercial off-the-shelf digital cameras for scientific data acquisition and scene-specific color calibration. J. Opt. Soc. Am. A / Vol. 31, No. 2 / February 2014.

    That's a good start.

  • Mamta Purohit added an answer in Pseudomonas:
    Does anyone have advice on lipase activity with tributyrin agar?

    Ttributyrin agar has been dissolved 20 g in 1 litre distilled water and  sterilized by autoclaving at 121°C for 15 minutes. It has been cooled to 80°C and added 10 g neutral tributyrin. But we couldn't see a clear zone, even by Rhodococcus spp. and Pseudomonas spp.

    Mamta Purohit · Gujarat University

    In spite of using tributyrene agar, you can also use nutrient agar medium and after autoclaving add sterile 1% tributyrene oil. You will get better contrast after lipase production by the studied isolates. 

  • Tomy Patzelt added an answer in Floods:
    Some countries in East Europe: Serbia and Bosnia, are experiencing destructive floods. What systems would be needed to prevent sudden severe floods?
    When I browsed, I find a few links:
    Is your expertise in this area? What systems would be needed to prevent sudden severe floods, in places that do not normally experience this phenomenon? Can you provide some helpful suggestions, so that water is a useful commodity, rather than a 'foe'?
    Tomy Patzelt · Czech Telecommunication Office

    I would suggest to check approaches practiced in Netherlands. They have about 70% of country under sea surface level and they dont have advantage of thirsty trees with ability to drink all the water from flash floods. Just a quick check revealed anything from barrier against 1500 yrs sea storm over various kinds of movable barries down to square before university, which is designed as pool able to concentrate several thousands of cubic meters of water.

  • Cretan Remus asked a question in Postmodern:
    Are postmodernists radically postmodern or they tend to be more close to poststructuralism?

    Many recent studies in different fields of social sciences have showed that postmodernists are not radically postmodern. Why do they turn towards a poststructuralist approach ?

  • Hani Antoun added an answer in Soil Analysis:
    What will I choose the ratio of extractant:soil between 5:1 and 2:1?

    How can I extract soil samples by extraction by DTPA-TEA solution at pH 7.3 (5:1 extractant/soil ratio or 2:1) for analysis of heavy metal availability in lead and TPH co-contaminated saline soil?

  • José Avila-Peltroche added an answer in Microalgae:
    Are there any recommendations for the P and N uptake rate calculation by microalgae?

    I have seen different ways to calculate P and N uptake rate and I don't know if there is a "standard formula" for this calculation.

    José Avila-Peltroche · Universidad Ricardo Palma

    Many thanks!! Actually, the aim of my study is to evalute the P and N removal of two strains of microalgae in wastewater for biorremediation

  • Has there been research to showing that increasing education improves ethics in a community?

    'Students often know the right thing to do. How can schools help them to do it?

    The numbers are in and they don't look good." That was the assessment of the Josephson Institute of Ethics last October, when they conducted a survey about the moral standards of more than 20,000 middle and high school students. Almost half the young people reported stealing something from a store in the previous 12 months. In the same period, seven out of 10 cheated on an exam.
    Should we be worried? Many observers say that we should. We see evidence of more antisocial behavior than ever among our youth—a sort of divorce between personal ethics and everyday behavior.'

    Has there been research to show that with increasing education, there has been improved ethics in a community?  Can you share, give some evidence? Thanks.

    Marcel M. Lambrechts · Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France

    Science practice:

    What are the behavioral consequences if you place students in a stressful unpredictable education environment versus a non-stressful predictable education environment?

    Prediction: The frequency of ethical behavior will be statistically highly significantly higher in the non-stressful predictable education environment.

  • Pablo San Segundo asked a question in Sinapis:
    How can I solve problems with the sequencing of a PCR-amplified cDNA cloned into pCR2.1 plasmid?

    Dear all,

    I have been trying to sequence a Sinapis alba (yellow mustard) seed PCR-amplified cDNA obtained from a cDNA library from total RNA (with the SMART-RACE kit).

    Once amplified from the library, I have cloned it into pCR2.1 plasmid in order to sequence it, but the signal suddenly falls (we think because of a secondary structure or a rich GC zone) and I just get the sequence of the C-terminal end.

    I have tried it several times, checking many times the plasmid concentration. I have also synthesized a new cDNA library from new RNA extraction (good quality checked). I have also tried to sequence it as a PCR product (not plasmid), and have also tried the BigDye dGTP kit (special for GC-rich sequences).  

    Any advice to get the complete sequence? 

    Thank you!

  • Is there anyone that made a physiological assessment with a IAPS set of pictures?

    I would like to know if anyone participated in a study, with a group of people, exposing to a set of IAPS stimuli and recording several physiological measurements. I would like to share experiences.

    Fernando Luis-Ferreira · New University of Lisbon

    Dear Martin Krippl, thanks for your input, i am reading your paper and it is an interesting add for my research. For me the most interesting issue in data collected is the GSR data; especially the values observed once the picture is displayed. I will post updates on correlations of collected data.

  • Nattan Stalin asked a question in Phage:
    Could anyone suggest me a method for purifying phages particles presenting the SM buffer for TEM analysis ?

    I toke TEM analysis for my bacteriohage.repetitively i got only salts images how to avoid the presence of salts during TEM analysis.

  • Chellaiah Muthu added an answer in Natural Products:
    How can I prove the herbivore repellent effect of a natural product?

    I isolate from plant herbivore repellent substance, how can I prove scientifically that effect?

    Chellaiah Muthu · Al Yamamah Company for Trading and Contracting, Saudi Arabi

    The research papers suggested by the Salman Ahmed would be much helpful to understand the techniques in identifying the repellent activity of the natural products.

    Feeding deterrent activity of the desired natural product can be tested using choice and no choice method. Among the two tests no choice test is the best option since the insect either preferred to eat or not to eat. If the insect is not at all eat the substance, then we can come to conclusion that the substance has repellent property. Some times the herbivory may eat the substance because, the product may attract the insects. After consuming the diet, the insect either die or growth inhibitory activities like malformation in larval-pupal intermediate, pupal-adult intermediate may occur.  By this way we can assess the natural products having repellent or attractant properties. A natural product may have repellent property to one insect but it is not so for other insects.

  • Helena Amaro added an answer in Sociology:
    Could you suggest me fundamental literature which focuses on the concept of "community"?

    I am particularly interested in works stemming from the field of anthropology/sociology. Thanks.

  • Larry Carlson added an answer in Philosophy:
    Can ethics be measured objectively?
    Ethics, ethical committee, ethical approval and other ethical related words are extensively used on Researchgate and other places. How to define and measure ethics in objective bases?
    Larry Carlson · United Tribes Technical College

    If I may ramble on here a little regarding my contention that Plato’s thought is not as a-religious and conceptually rarefied and hermetically sealed as it might at first blush seem to be, but rather welled from religious thinking that flowed from one culture to the next.

    The word “influence” in any study of culture reminds us of the flow of ideas, attitudes, ideas, beliefs, and styles from one area to another throughout history like a stream with may tributaries. So I ask from whence came Plato’s ‘conception’ of justice and to whom was it passed along?

    For Plato, ‘justice is “the having and doing of one’s own and what belongs to oneself."  Excess and deficiency of any kind are unjust. In this formulation the Platonic definition of justice seems plausible. A thief, for example, is unjust because he wants to have what is not his own. A doctor who does not care about curing his patients of illnesses can be called unjust because he is disregarding his proper role. A murderer acts unjustly since he deprives his victim of that which rightly belongs to him, namely his life.’

    Wright, Chris. Plato’s Just State. Philosophy Now, Nov/Dec, 2014

    This sounds very much like Hinduism, does it not? According to Sanjeev Sabhlok, Plato’s “Republic has a direct relationship with India's caste system. Everything in the Republic is very close to the Vedic system: the three main varnas, the limits to inter-breeding, the rule by philosopher-kings (Brahmins), and a deliberate mythology (Noble Lie).”

    This claim is put forth by a number of writers, e.g., Lomperis parallels Plato’s three classes with India’s caste system in his book, "Hindu Influence on Greek Philosophy, The Odyssey of the Soul from the Upanishads to Plato."

    We know that Augustine was influenced by Neo Platonism, and that Calvin was influenced by Augustine. We also know, of course, that a sort of rigid class/caste system permeated Europe in the feudal system of the Middle Ages. Though notions of equality eventually gained the upper hand, both Calvinism and Christianity in general were loath to make any hasty, radical attempts to overturn the inequalities inherent in the social system, i.e., a master-slave relationship in which ambition and usurpation were seen as major social sins.

    (The sanction against ambition permeates Western thought: Shakespeare’s Brutus says of Caesar, “"As he was ambitious, I slew him” and Macbeth foretells his own doom as he broods that, “I have no spur to prick the sides of my intent, but only vaulting ambition, which o'erleaps itself, and falls on the other [side].”)

    A good overview of the flow of this notion of not upsetting the social hierarchy by attempting to step outside one’s calling or “voca-tional” niche is found on page of Abraham Kuyper’s “Lectures on Calvinism,” in which he traces the flow of the “world-stream of [cultural/intellectual] life” from India>Middle Asia, the Levant>Babylon, Egypt, Greece>Rome>Western Europe/Romantic nations>Northern Europe (Holland, England)>The Eastern States of the U.S.>the rest of the U.S. (p. 20).

    Of course the exact flow of influence depends upon which particular idea, artistic style, etc. under discussion, but the general flow of ideas, etc. is often traceable. So no, the Greek philosophers in general were not discoursing in some academic void of reason far from the madding cry of religious moral discrimination.

    By the way, a less favorable view of the ‘caste-like’ nature of Calvinism is painted  in the Dark Side of Calvinism, The Calvinist Caste System” in which we read that “according to Calvinism, in order for a lost person to become a saved person, he must be among a special caste of humanity called the elect. While the caste system of Reformed Theology transcends the earthly distinctions of humanity (i.e., rich, poor, black, white, Jew, Gentile, highly cultured, lowly peasants, etc.), it is an undeniable feature of Calvinism.
    http://www.bibelkreis.ch/Calvin/The_Dark_Side_of_Calvinism.pdf (Bryton, Smith)

    My point is not to cast stones against those who wish to erect walls between classes or castes, but rather to point out that any hierarchic system is ‘bound’ to create simplistic, intransigent, and partitioned views of morality and sanctification. Hence, any such categorical divisions naturally lead to black/white views of what can be deemed as righteous and ethical.

    On the other hand, I can’t help but note that some sects and nations want to have it both ways, e.g., attempts by Americans to claim that they are a classless society...really?

  • Ziad Abu El-Rub added an answer in Gasification:
    Is there a recent update on the tar protocol for measuring the tar content in the producer gas in biomass gasification systems?

    There is no standard method for measuring the tar content in the producer gas in biomass gasificatin systems. However, there has been a protocol developed early in 2000 in a step to reach a standard. Has this protocol been standardized?

    Ziad Abu El-Rub · German Jordanian University

    Thanks all for your reply. What about using the SPA (solid phase adsorption) method. Is it accepted nowadays for measuring the tar content?

  • José Guerreiro added an answer in GPRS:
    Which is the best option among android phones, beagleboard/Rasberrypi or ardino for the below task?

    I basically want to collect data and send it to some remote location.

    There could be three ways I can accomplish the task:

    1)I can use my android phone to collect data from and use the phone gsm itself to send the data to remote server.(requires no much skills)

    2)Use beagle board black and attach BeagleBone GPS/GPRS Cape and program the device(requires me to interface the gps/gprs cape )

    3)Go to even low level boards like ardino and use gprs shield 2 to program the same.(may require low level interfacing)

    So out of all the above options I would like to know which one is the best option in terms of battery, portability, programming ease and efficiency.

    My basic aim is to collect data from ethernet to the device and send to other location using gsm.

    I can use usb to ethernet interface for mobiles.

    José Guerreiro · Institute of Telecommunications

    I can understand that using a mobile phone could be expensive that other option which you are thinking for. But, since you have realised that it is not hard to be implemented, then go ahead ;)

  • Saeed salimian rizi added an answer in Laser:
    How can we calculate the small signal gain of a laser amplifier?

    There is a formula in koechner that go=Ep/ηl

    Ep= pumping energy

    l=cavity lenghth

    η = ηtηaηSηQηBηStηASE/AES

    But in this formula there isn't any coefficient for dopant density. For example Nd:YAG.

    Saeed salimian rizi · Shahid Beheshti University

    My question is how can we calculate small signal gain of a laser but in the formule that I mention above there is not any relationship between g0 and dopant density.

  • Buerhan Saiti added an answer in Time Series:
    How many minimum number of observation are necessary for ARDL model ?

    I am using quarterly time series data set with 40 observation. I have developed a model with this much number of observation. Please suggest me this much observation are sufficient or not. 

    Buerhan Saiti · University of Kuala Lumpur

    please go to the following link: there is a detailed discussion on this topic. 


  • Edward Zamble asked a question in Co-authorship:
    This is definitely not mine and I've never seen it before; is it a review?

    The title is that of a monograph by myself and Porporino published by Springer-Verlag in 1988.  Was it a review by Ellis, the title of which somehow became conflated with co-authorship?  Please correct it.

    Edward Zamble

  • I need some research models which shows impact or effect of demographics on attitude formation?

    I need to do research which could be titled as "Role of market segmentation on attitude formation and consumer purchase behavior"

    So if you have any good literature review on this it would be great.

    Research models are mostly welcomed.

    Mohammed Nadeem · National University (California)

    Hi, Emir:

    Purchase behavior is a fantastic topic to research! I suggest you take a look at the following recent research model:

    This study (Wu and Chan, 2011) aimed to explore the impact of perceived service quality and self-concept on consumer attitude and purchase process using channel type (physical and Internet) as a segmentation variable.

    The authors argued that from the perspective of consumer behavior, this study attempted to estimate a relational model and perform an empirical validation using female cosmetics and skincare products as an example.

    The authors discovered that the influence of perceived service quality and self-concept on consumer attitude, purchase intention and behavior, satisfaction, and loyalty varied with channel type. The analysis result revealed that physical stores presented higher levels of agreement with all research perspectives than Internet stores. However, only two relational paths have a higher influencing effect in physical stores, and the correlations among almost all of the perspectives are stronger in Internet stores. Therefore, if Internet stores enhance their service quality and understanding of a consumer's self-concept, they can enjoy the effect of such an enhancement through a boost in consumer attitude, purchase intention and behaviour, and even in satisfaction and loyalty!

    • Wu, S., & Chan, H. (2011). Perceived service quality and self-concept influences on consumer attitude and purchase process: A comparison between physical and internet channels. Total Quality Management & Business Excellence, 22(1), 43-62.

    Hope this helps!


  • How can I prepare phenyl 2-cyanoacetate with high yield and purity?

    Thanks in advance for your replies.

    Isaiah Omolo Ndiege · Kenyatta University

    Start from phenyl malonate, reduce one ester group to an aldehyde, react the aldehyde with chloroamine 

  • Gloria E Hoffman added an answer in Avidin:
    How can I reduce background on liver tissue in immunohistochemistry?

    I am currently optimizing a new biotinylated primary antibody. It works great on brain tissue but I am encountering background with liver tissue. I am using avidin, biotin and hydrogen peroxide as blocking agents. Is there something else I should use to pretreat these liver tissues? Any help would be greatly appreciated. Thank you for your time.

    Gloria E Hoffman · Morgan State University

    A superb way of using biotinylated primaries is to follow it with ABC making the anti-biotin (goat) behave as the "primary antibody in the reaction.  You would still need to control for endogenous peroxidase (as mentioned previously), but I have learned that adding "normal" serum is not effective.  Instead a thorough titration of the primary antibody and the anti-biotin will usually eliminate the background while increasing signal to noise ratios. See this article for examples of proper titrations (you should note that some antisera will give good signals in the millions whereas for others 1:1000 is as dilute as you can go.  Unfortunately if the antibody is no good, no procedure will help. 

  • S G Deshmukh added an answer in Learning:
    Do you agree with Daphene Koller's view on what we are learning through on-line education?

    On line education is the in thing and is going to alter the way we learn and form our world view. Do you agree with this. Here is an interesting view put forth by Daphene Koller.

    S G Deshmukh · Indian Institute of Technology Delhi

    Dear Geigel,

    Thanks for your quick and succinct response. I agree . There are transmission losses also which makes the teaching -learning process more challenging. Automation combined supplemented with supervisory learning can be a good hybrid approach to reduce the transmission losses.

    Happy Xmas 


  • Amit Kumar Mishra asked a question in Milk:
    Any suggestion on topic to write a project on breast cancer??

    Breast cancer is a kind of cancer that develops from breast cells. Breast cancer usually starts off in the inner lining of milk ducts or the lobules that supply them with milk. A malignant tumor can spread to other parts of the body.

  • Andreas Thomsen added an answer in Collagenases:
    What is the best method to culture MSC's from cord tissue?


    I am trying to culture MSC's from cord tissue but I keep getting endothelial cells instead. I am using 0.075% collagenase and 0.125% trypsin and incubating for 45 mins at 37°C while shaking gently. I have tried doing doing this about 4-5 times and tried changing the collagenase concentration and incubation times but I keep getting endothelial cells. Can any one please help me out with some suggestions.


    Andreas Thomsen · University of Freiburg

    Hello Tatenda,

    another option that worked quite well is to remove the umbilical arteries and the vein, because these are the only sources of endothelium within the cord.

    All you need is a strong anatomical forceps in each of your hands and a good grip:

    - place a 5-10 cm section of the cord into a large Petri dish
    - grasp one end of the cord with one forceps and pull away a piece of tissue with the other one.The outer portion of the cord tissue has an amazing tensile strength, so with a bit of practise you will manage to rip off long strips of cord tissue, which you may directly transfer into your collagenase. 
    - as soon as you have exposed the vessels, pull off the two arteries and then the vein. This is hard work, as 'Wharton's jelly' is much tougher than any other jelly ;-).
    - the remaining tissue is ready for digestion - I agree with Ajay that collagenase alone will do nicely.

    If you retrieved fine strips of cord tissue (< 1mm in diameter), you may also try explant culture, which worked well in DMEM/F12 (1:1) with 5 % of human serum. Just resist to move your culture vessel during the first 3-4 days of culture.

    Finally, you should know that cord tissue MSCs are more polygonal and less spindle-shaped than bone marrow MSC.

    Hope this will be of help,

  • How can I do a structural break test on ARMA model in R?

    Is there a way to do a structural break test such as Chow test on ARMA model in R?
    I haven't been able to find a way to do this. Strucchange package doesn't accept objects from arima() function. Or is there a way to write out the ARMA equation in R so I can use lm() function and do structural break test?

    Thanks a lot.
    Buerhan Saiti · University of Kuala Lumpur

    now the most hot method is markov switching to test the structural break… you try to learn this method and you can publish in top journal. 

  • Parviz Parvin added an answer in Space Time:
    Is the flow of time an illusion?
    This has been discussed on ResearchGate in a rather ad hoc way in relation to another question about the absolute immutability of some physical laws but it really deserves its own separate discussion. Below I summarise the arguments in favour.
    The philosophers
    The nature of time has been the subject of discussion by philosophers for 2000 years or more. In the last two decades their views have crystallised. If time flows - (1) How do we know? and (2) How do we measure its speed? In other words - what frame of reference can we use to measure time?
    The philosophers' conclusion is that they would have to invent another time dimension for the purpose but this would then need a third time dimension and so on ad infinitum. This would be absurd and so they conclude that the flow of time is an illusion.
    Relativity, Einstein and Godel (A World Without Time - Palle Yourgrau - Penguin Books, 2005)
    According to the theories of relativity two observers can never agree on the simultaneity of two events that both witness and neither has a "preferred" position that makes one of them correct. This implies that all events already exist and that what we perceive as the flow of time is an illusion.
    Godel showed that rotating universes were consistent with relativity and proved that in them it was possible to travel back in time. He immediately realised that this implied that the past must still exist and that what he called "intuitive time" is therefore an illusion. In 1949 he published a formal proof that time (in our intuitive sense) cannot exist in any universe. This uncomfortable discovery was ignored for nearly half a century but was revived by Julian Barbour in "The End of Time" and is now widely discussed and accepted by many physicists.
    The Laws of Physics
    The fundamental laws of physics describing the forces are time-symmetric.
    What can we say about the time dimension?
    Time still exists but only as a chronological map in which events are located;
    Time is not in any way like the spatial dimensions because:
    It is anisotropic and contains an entropy gradient;
    If we exist in more than one location in any of the spatial dimensions then we will also always then be in different locations in the time dimension;
    Separations in 4 dimensions are extensions of Pythagoras's Theorem but have the form:
    separation = √[x2 + y2 + z2 - (ct)2], which means that time measurements are imaginary (ict) where i=√(-1), as Hawking suggests in "A Brief History of Time".
    Free will is also an illusion
    We live all our lives all the time but every instant feels like "now"
    Time travel is impossible because (a) there is no dimension in which travel is possible, (b) we occupy all the spacetime of our lives and cannot take back to an earlier time our memories of a later time.
    Parviz Parvin · Amirkabir University of Technology

    Time travel is impossible and a science fiction. Time is a unidirectional arrow.

  • Buerhan Saiti added an answer in Financial Markets:
    Is there anyone who can give me some advice for starting a research on stocks and financial markets?

    I want to work on problems in field of stock (basically I prefer working on wall street market) but I don't know how I can do it and which subjects could be helpful.

    Buerhan Saiti · University of Kuala Lumpur

    For me, you can choose several stock markets' data ( based on your reasonable choices) and run some basic description of data, and observe what was happening with the data, then you can drive some interesting facts, some interesting issue in stock markets are cointegration, spill-over, contagion, lead-lag analysis, diversification, co-movement, volatility, cross-correlation, etc… 

  • Dharmesh J Bhalodiya asked a question in SQL:
    Can anyone help me to find out for how many open source GPU base database available?

    Hello friends.

    like always, you helped me. i ask another question.

    we are conduction survey on GPU based database. for that we need SQL processing algorithms and respective Paper/article published still now...

    I have also tried and i get following database

    So please help me by replaying other database (SQL Query processing algorithms) link

    and Thanks in Advance...