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  • Hanno Krieger added an answer in Crows:
    Are crows intelligent?

    In common language, some people use the phrase "bird-brains", but this may be very unfair to birds, and show only the ignorance of those people!

    A recent research paper titled, "Crows Spontaneously Exhibit Analogical Reasoning" was published by Anna Smirnova, Zoya Zorina, Tanya Obozova, Edward Wasserman in Current Biology, 2014 DOI: 10.1016/j.cub.2014.11.063.

    Based on this, a general article was published recently- see link! Some excerpts:

    "Crows have long been heralded for their high intelligence -- they can remember faces, use tools and communicate in sophisticated ways.

    But a newly published study finds crows also have the brain power to solve higher-order, relational-matching tasks, and they can do so spontaneously. That means crows join humans, apes and monkeys in exhibiting advanced relational thinking, according to the research.

    Russian researcher Anna Smirnova studies a crow making the correct selection during a relational matching trial.

    "What the crows have done is a phenomenal feat," says Ed Wasserman, a psychology professor at the University of Iowa and corresponding author of the study. "That's the marvel of the results. It's been done before with apes and monkeys, but now we're dealing with a bird; but not just any bird, a bird with a brain as special to birds as the brain of an apes is special to mammals."

    "Crows Spontaneously Exhibit Analogical Reasoning," which was published December 18 in Current Biology, was written by Wasserman and Anna Smirnova, Zoya Zorina and Tanya Obozova, researchers with the Department of Biology at Lomonosov Moscow State University in Moscow, Russia, where the study was conducted.

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    I´ll try to give some hints. If you define inteligence as rational act of the brain, you shoud not ask can birds be scientists, you should try to find out if do they rise their decision above their feelings and mind.

  • Marcel M. Lambrechts added an answer in Moon:
    Christmas question: What is the scientific verifiable evidence that at least one human walked on the moon?

    Perhaps some people still believe that the Apollo missions to the moon were fiction? How to convince these people that at least one human indeed walked on the moon?

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

    Non-believers will also not believe non-believers I presume?

  • Farzad Khanipour added an answer in Aptamers:
    Does anybody know about the Structure of AS1411 quadruplex forming aptamer?

    Is it a single stranded self-quadruplex or a double stranded quartet forming aptamer?? please check the files and comment. I'd really appreciate it.

    Farzad Khanipour · University of Guilan

    Dear Marc 

    Thank you very very much for the precious time devotion and this excellent response.

    I totally agree with you will read the paper you shared 

    Thank you again

    Best regards

  • Andrew Simpson added an answer in Evolution:
    Does "Big history" as an exhibition/ education concept work for natural history or mixed museums?

    Do you have any experience with big history/ universal history exhibitions as well as courses for high school classes, especially:
    - comparison of natural and cultural processes which work at different time scales (from years to billions of years)
    - look at historical events (e.g. political turnovers, economical crises) from different points of view, i.e. study of written reports vs natural archives/ scientific data
    - evolution as a (meta)concept that includes biological evolution, but also evolution of the universe, planetary evolution, abiogenesis, cultural evolution, evolution of mind
    - answer to the question whether and to what degree history is determined by changes in environmental conditions (e.g. climatic forcing)
    - transition from humans as minor constituents of land ecosystems to humans as ecosystem modellers and from early artefacts to written language

    BTW: Is "big history" already out of fashion due to certain weak points (i.e. re-introduction of anthropocentrism and historicism into scientific discourse)?

    Andrew Simpson · Macquarie University

    The useful thing about "Big History" is that it provides a teaching framework that breaches the natural and cultural worlds by nesting culture within nature.  At Macquarie University where it has been used in teaching for a while, each year the history department would ask the scientists for objects that illustrate the signposts of increasing complexity, ie. a meteorite, banded Iron sample, Ediacaran fauna, vertebrate remains etc. 

    Many years ago I did a small exhibition in a university museum on the history of the Earth.  It changed my perceptions about the nature of museum work.  Try capturing 4.6 billion years with only a small number of specimens, it focusses thinking and provokes many interesting discussions.

    The "Big History" framework can be presented to people in small spaces and with small collections, it is just more challenging (and fun!).

  • Is the Nuremberg Doctrine a failure?

    The latest revelations about CIA torture methodologies demonstrates that medical doctors took part in what is euphemistically described as Enhanced Interrogation Techniques.  How is it that an international doctrine prohibiting medical doctors from involvement in torture has failed in one of the countries that presided over the Nuremberg Trials?

    Can we trust any nation that employs doctors in torture to simultaneously apply the principalist ethic Primum non Nocere in its hospitals and medical practice generally?

    Should those 'medics' be identified and disbarred for life from medical practice? 

  • Do you have any recovery issues with lipophilic pesticides?

    With sample:solvent ratio of 1:2 (5 g with 10 mL acetonitrile), you have good overall recovery. I used 0.5 g of oil with 30 mL acetonitrile just to maintain amount of oil at 0.5 g for fear of damaging the GC column. The idea of freezing should help out a lot to get rid of the oil. The method is good for lower the LOW to 10 ppb.

    Narong Chamkasem · U.S. Food and Drug Administration

    For normal analog detectors such as UV or ECD, you measure the noise level of the baseline, the analyte concentration giving 10 times the noise, is LOQ. However, GC/MS/MS has no noise. You can keep lowing the amount of the analyte, but the noise will be flat. Until you don't see the signal. What you do is inject a few lowest standard solution and calculate the standard deviation. LOQ = 10 std dev.

  • In site directed mutagenesis, can it be using the template (plasmid) as a vector also?

    when making a mutation in a gene via site directed mutagenesis, could be normal to use the template as a vector to clone the gene or not?

    Hêro Akrayi · Salahaddin University - Erbil

    Dear Lei Wang, 

    thanks so much for your answer, but my question was not about using plasmid as a template; I have meant if I use a plasmid as a template then could I use the same plasmid as a vector for transforming particular bacterium?

  • What are the main human factors that affects information systems?

    I am researching into the human factors and their impact in information system productivity. What are the main human factors that affects IS productivity and efficiency.

    I am considering variables like Age, Gender, Education, training etc

  • Xin Hong added an answer in Real-Time PCR:
    Is it ok to use pooled sample as reference sample in real-time PCR?

    I am working on U87 & U251 cell lines, after treatment in trplicates isolated total RNA to cDNA. While doing real-time PCR can I use pooled cDNA from triplicates as reference sample for each experiment or/and can I use the same for all other real-time PCR expt. Please suggest me any other ways is there.

    Xin Hong · Massachusetts General Hospital

    Yes, you can. It is just that this will be considered one biological repeat if you do statistics to measure the significance of differences between your control and treatment. 

  • Alexander Chovan added an answer in Foraging:
    What a foraging connections can have Black-headed Gull (Larus ridibundus) with Goldeneye (Bucephala clangula) during migration?

    Is there who study these species? During autumn migration of waterfowl on the Kiev reservoir (Ukraine) I observed many flocks of Goldeneyes. Flocks of Black-headed Gulls always were fed with them together. What cause of this occurrence?

    Alexander Chovan · National Taras Shevchenko University of Kyiv

    Dear Nicola Baccetti

    Thank you for your answer.

    Kind regards,

    Alexander Chovan

  • Sri Vadana asked a question in Collision Avoidance:
    How do we write a matlab code for potential fields in collision avoidance?


    collision avoidance

  • Majid Pasandideh added an answer in Horses:
    Why i find a hight Linkage desilibrium in a breed horses (Arab-Barbe)?

    but this breed is created 14000 YEARS ago??

    Majid Pasandideh · Sari Agricultural Sciences and Natural Resources University

    LD can occur due to, mutation, migration, selection, small finite population size or
    other genetic events which the population experiences. In livestock populations, finite population size is the most important factor causing LD.

  • Mustafa Barbaros DUZGUN added an answer in Diatoms:
    I try to purify a protein (DEAE) but it stays with pigment and go out with wash (Pi 6.3 ; buffer pH 7.9) : have you ever met this problem ?

    I work with a diatom

  • What is the most important factor of learning? And why?
    Is it the environment? Learner's attitude? concentration? motivation? engagement? IQ? repetition? experience? and so on.
    Hristina Petrova · Plovdiv University "Paisii Hilendarski"

    Passion or even better <curiosity driven by passion>. The key elements here are  knowledge, drive, interest, imagination, inspiration, spirit, perhaps even common good.

    Emotions are a strong factor. I am particularly interested in and dependent on a personalised approach (good teacher or mentor) which is a strongly emotion-driven approach. I am still looking for like-minded individuals in research (but at the same time people who are much more experienced than me) and I have the intuition that I will find them either in industry or yet again at a conference (rather than academia), and like so many times before, support will come from an American or a Canadian which is an aspect of their sensitive attitude to helping young people achieve their learning goals and realise their potential. In other words, emotions are important to the extent that their cultural dimension could motive as well as demotivate learners no matter how knowledgeable, positive and hopeful they might have been initially. 

  • Do you think whether it is proper to connect gravity exclusively with the speed of light?

    Since the beginning of the twentieth century the speed of light is thought to be fundamental to gravitation and its transmission effectiveness. Mathematical physics seeks whether this idea is sufficient for explanation of all phenomena related to mass attraction. Is a change of position needed? What is your opinion?

  • Can you suggest an easy identification method for metals in water and soil?

    If possible with cheap instrumentation, in situ or in laboratory.

    Dieter Wolfram Zachmann · Technische Universität Braunschweig

    Help Sofane,

    focusing on data turnover in metal analysis of waters and soils ICP-OES is certainly cheaper than AAS (as A.R. Karbassi points out). The turnover factor between ICP OES and flame-AAS is in the range of 20 to 30 (ETAAS even very much slower). Also, considering the number of different elements you might be interested in ICP is much more versatile than AAS (e.g. carbide forming elements should be done by ICP (Si, Al, Nb, REE etc). On the other hand, to purchase, install, and maintain an ICP is much more expensive than flame-AAS. In addition, for ICP you need lots of Argon as operating gas (about 1000 L/min), which is quite expensive and procurement logistics might become difficult. For flame-AAS you need about 80 L/h of acetylene (and some pressurized air (by compressor device); so a standard pressurized bottle of acetylene (50 L; 200 bar (20 MPa)) will be enough to operate an AAS device for about 120 h (Ar for ICP: 10 h). Acetylene can be purchased cheaply and nearly everywhere. Also the installation and handling of the device is very easy as compared to ICP. The only inconvenience in AAS is that you need a specific AAS-lamp (specific wavelength) for each element you are interested in. The average price is about 250 Euro (to my experience); the live time is warranted for about 2 years. Most of my lamps are much older than 10 years and still well operating, and by time you will get a collection of lamps. So, if you are just interested in alkalines, earth alkalines, the main heavy metals (e.g. Fe, Mn) , and trace metals of environmental relevance (Co, Ni, Cu, Cd, Pb etc.), and if you have not too many samples, I would suggest to try flame-AAS. In many cases of normal environmental questions the sensitivity is good enough. If necessary, you could extend the AAS method to the hydride technique (As, Se, Hg; very sensitive) or graphite furnace (ETAAS; very sensitive - not so easy). When I am interested in just one type of element in a restricted number of samples I prefer AAS to ICP because in this case the data retrieval is easier, cheaper, and, above all, faster (30 – 40 samples/hour). Of course, you have to consider state of the art when performing AAS analyses; this is, however, also true for ICP. In summary, when starting with analytical data acquisition I would prefer flame-AAS as a relatively cheap and easy to handle technique.

  • Could anyone help me with a tool (suggest any effective method) that could be used to assess changes in rainfall variability over a period of time?

    I conducted a survey to assess farmers' perception on climate change and found out that their views on temperature were true on analysis of observed temperature data but views on rainfall were difficult to assess with observed rainfall data. While they think rainfall amount had decreases over the past study period, analysis of rainfall trend does not prove so. I therefore think that, apart from possible increasing trend of PET due to increasing temperature, possible increasing trend in rainfall variability over the period could account for their perception. Hence, I wish to assess rainfall variability trend over the study period.

    Thanks in advance.

    Carlos Martins Vila-Viçosa · University of Porto

    Here you have two nice Investigators to ask, follow, and work...



  • Do you know research in the field of cognitive science on the subject of knowledge creation?

    I am researching if space can foster innovative thinking and would like to know if there is any literature on knowledge creation in the field of cognitive science?

  • David L Morgan added an answer in NVivo:
    Can you suggest me some ideas about which tools in NVivo should be used to support relationships in a qualitative framework?

    A reviewer of our journal paper has suggested that “Nvivo has tools for the construction and testing of answers to research questions”. The reviewer expects a discussion on which the relationships in the (qualitative) framework are in fact supported by the NVivo analysis. I’m not sure what the reviewer is referring to here. Can you suggest me some ideas about which tools in NVivo should be used to support relationships in a qualitative framework?

    David L Morgan · Portland State University

    It seems to me that you have two basic options in your revisions. The first is to try to do what the reviewer asked, and find some "tests" for the relationships that you are evaluating. the second is to revise the portions of the paper that led the reviewer to make this essentially inappropriate request. In that case, your letter to the editor will be essentially apologetic for creating the possibility of misinterpretation. (In other words, the problem was due to your mistakes, not the reviewer's -- sigh.)

    There is actually a third option, which is to contact the editor to explain the situation and ask for clarification. I can still remember the first time I had to find the courage to use that option, and it also involved a confusion about using quantitative approaches in qualitative research. My own experience was quite positive, so you might try the same, especially if the journal you are working with publishes a fair amount of qualitative research, so that the editor may be familiar with the general issue.

  • Marc Tessera added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Louis and Simon,

    When I read something like "It is about asking the right question" and "The kind of intelligence required to ask the right question is radically different from that required to get the right answer. And indeed, the right answer to the wrong question is worthless" I think of a kind of ideology. Every ideology wants to say what is right and what is wrong.

    To me there are not right or wrong questions. Every question may be asked by anybody.

    Of course a given question may be not put the best way, i.e., a way that facilitates possible answers. However I would never say that somebody was wrong to ask a given question, even questions which likely have no answer, like "why is there anything rather than nothing?". 

  • Simon C Duff added an answer in Emotional Trauma:
    Can anyone recommend articles/studies which focus on the link between personality disorder and domestic violence?

    I work in acute mental health services and would like to do some research surrounding personality disorder and domestic violence.

    Patient type: Females aged 16+

    Diagnosis: Borderline Personality Disorder preferred however all personality disorders are of interest. Suspected personality disorder are also of interest. 

    Patients must have experienced some form of domestic violence (physical, sexual, financial or emotional) past or current. 

    There is an abundance of evidence to show that mental health illness and domestic violence are closely linked. It has become expected that domestic violence victims will experience some form of mental illness as a result of the abuse however early intervention is not being achieved whilst mental health professionals are not acknowledging it's contribution to the person's illness. 

    Whilst domestic violence is often only targeted at one person, the effects can be detrimental to the whole family. There is an increased risk of behavioral problems, emotional trauma and mental health difficulties in adult life for children who are subjected to domestic violence in their family home. It is becoming increasingly difficult to ignore that domestic violence is a widespread social issue and the children exposed to it today could potentially be the service users of tomorrow.

    Simon C Duff · University of Nottingham

    Here are some links, hope they are useful;




  • What is the most suitable material to reduce the effects of radon in soil?

    Soi gas radon concentration

    Dr. Abd Elmoniem Ahmed Elzain · Department of Physics - Kassala University - Sudan and Department of Physics - Qassim University - Saudi Arabia

    Thank you very much Dr. B.K . Bhaumik,  for your useful answer and contributions. 

  • What is the more accurate to measure radium content from water samples is it the active or passive methods of measurements?

    Water radium content

    Dr. Abd Elmoniem Ahmed Elzain · Department of Physics - Kassala University - Sudan and Department of Physics - Qassim University - Saudi Arabia

    Thank you very much my Dears for your answers. 

  • Jason Rosenzweig added an answer in Blood:
    Does inflammation affect the use of polymorphprep?

    I have been trying to separate different cell populations from whole blood using polymorphprep, I have blood from the same subject taking over a time course (with inflammation induction after first sample). The first sample separates without issue but the red blood cells don't sediment properly in the follow up samples. Is this an issue with polymorphprep? Does anyone know if it is related to the inflammation or just a coincidence?

    Jason Rosenzweig · Johns Hopkins University

    If you don't think it will affect the rest of the cells, you could try lysing the red blood cells before polymorphprep separation.

  • How can I confirm that I have harvested sulfate reducing bacteria?

    I am working on microbiologically influenced corrosion of cast iron, I used 1249 Baar's medium to grow SRB (D.Vulgaris) in an anaerobic chamber. Because of increased turbidity, I know something has been grown in my culture but how can I make sure it is SRB and not some other bacteria?

  • Can someone help me with the interpretation of results obtained by docking study (SwissDock)?

    Could anyone help me in the interpretation of results obtained in SwissDock. What I am not sure is how FullFitness is related to Delta G and which of these two values is more related to the true affinity of ligand to target. Besides, I would like to know if I can compare affinities of the same compound toward different proteins.

    Thank you in advance.

    Prof. Ravi K. Sharma · Central Drug Research Institute

    Just see this link


    For step wise approach please see  this paper


  • What is the max temp. for rotary evaporator in extraction for phenolic comp. and saponins from cosmos caudatus leaves in 50% ethanol?

    you know that boiling point for water is 100C . so can i set temp. on 100C. and my extract will not damage?  

    Prof. Ravi K. Sharma · Central Drug Research Institute

    Also see this thread:

    How to extract ingredients in medicinal plant without destroying their natural values?

  • Does anybody have any experience or knowledge about quality of water harvested from air?

    I have harvested water from air and measured by YSI device some water quality parameters (pH, TDS, DO and Salinity etc.) under the home condition. At the 20.1°C temperature, pH=7.26, TDS= 88.40 ppm, Salinity=0.06 ppb, DO=4.1 ppm like that.

    Air humidity is very important for semi-dry and dry ecosystem in terms of living organism especially for plants. So, by determining quality of water in the air may be we will open new gates in different ecosystem in terms of plant health.

    Joaquín Navarro Hevia · Universidad de Valladolid

    Another paper about fog water quality:

    ESPEJO, R., MARTÍNEZ, L. GUTIÉRREZ, G. y GIODA, A. 1996. Variabilidad temporal de la calidad del agua de niebla en el norte de Chile. II Encuentro Internacional de Físicos de la Región Inka. Cuzco. Perú. 10-14 de junio de 1996. 9 p.

  • Prof. Ravi K. Sharma added an answer in Docking:
    How can I dock a large ligand?

    Hi. I want to do protein-ligand docking. But the ligand is large and flexible with 546 rotatable bonds set TORSDOF 546. I have two questions: 1. When I used autodock4.2 I received this error:"too many torsions. maximum number of torsion is 32". How can I solve this problem? 2. Can I use vina for this system?

    Best Regards.

    Prof. Ravi K. Sharma · Central Drug Research Institute

    please see this site