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  • Shanette M. Harris added an answer in Self-Esteem:
    Female self-esteem
    Studies have shown that female adolescents possess a lower self-esteem when compared with their male counterparts, has any study proven otherwise?
    Shanette M. Harris · University of Rhode Island

    Hello Dr. Dara:

    A large number of studies show that the finding of gender differences in self esteem with females reporting lower esteem than males (including body esteem) is more often the case for White Americans or European heritage males and females than some other populations.  This is particularly the case for African American females (who might be thought to have low esteem given the challenges they must face). Adams (2010) for example found that African American adolescent females report significantly less self deprecation than their same age White female peers.  A longitudinal study with African America women yielded similar results in that high levels of esteem were found across three decades (Patterson, 2004).  Using the words "woman/women", "girls" and "females" without reference to more specific race/ethnic and cultural information can easily lead to confusion and inaccuracies about results and findings that hold only for some female groups.  Interestingly, the differences in body image attitudes overall might relate to differences in esteem as well as other factors.

    I hope this adds to your thinking about the topic.

    S. Harris

  • Can anyone list some of the definitions of green supply chain performance and also state the constituents of green supply chain performance?

    in short what are the constituents of green supply chain performance?

    Mohd. Asif Gandhi · Anjuman-I-Islam's Kalsekar Technical Campus


  • Gianpiero Colonna added an answer in Chemistry:
    Can anyone explain briefly the difference between the equilibrium and steady state system in chemistry?

    A system in a steady state means that the rate of change is Zero! what about the system which is in equilibrium? 

    Gianpiero Colonna · National Research Council

    As the word itself says steady state means something that does not change in time. Thermodynamic Equilibrium is the steady state for a closed systems and all the reactions are equilibrated with the its reverse process. Therefore, due to the detailed balance principle, is does not matter what is the rate of each reaction, but only the equilibrium constant. In general, also the real reactions are not important, because, at equilibrium we can define arbitrarily a minimum set of reactions that allow us to determine which is the equilibrium state. Given N specie formed by N atoms we need N-n independent reactions to define the equilibrium state. 

    A non-equilibrium steady state is obtained in open systems, when energy and/or mass are injected continuously. It is the case of an DC electrical gas discharge in low temperature plasma. Usually in non-equilibrium steady state, the transition to equilibrium is manifested by the spatial inhomogeneity. To understand the concept you can consider a vessel full of water with a hole in the bottom. The equilibrium state is the empty vessel, but the if you fill with water on the top, with the same amount of water that is lost from the bottom, the water level remain constant. 

  • Lisa Zimmermann added an answer in Business Models:
    Do you know any quantification for business models?

    I am looking to map the business model in an entire industry, so I am looking for a valid instrument to use it in a survey.

    Lisa Zimmermann · Université de Fribourg

    Amit/Zott ?

  • Jacques van Rooy added an answer in Shorebirds:
    Does anybody know exceptions to the Latitudinal Diversity Gradients (LDG) among plants?

    The majority of organisms/taxonomic groups follow the Latitudinal Diversity Gradient (LDG), e.g. the increase in species richness from poles to the tropics. There are some rare exceptions, mainly discovered & published for animals (e.g. penguins or shorebirds) but rarely for plants (e.g. grasses). Recently we have demonstrated the same atypical gradient in gymnosperms. Who knows other plant groups/families which do not follow the LDG?

    Jacques van Rooy · South African National Biodiversity Institute

    I would like to commend Sean Haughian on his answer referring to bryophytes. Several recent studies could not find conclusive evidence for a latitudinal diversity gradient in moss (Bryophyta) species richness - see Global moss diversity by Geffert et al. (2013) J. Bryol. 35(1): 1–11. DOI: http://dx.doi.org/10.1179/1743282012Y.0000000038

  • Jacqui B Jeavons asked a question in Social Isolation:
    Do you feel that living in apartment buildings contribute to social isolation and depression?

    Could an increase in shared facilities (indoor and outdoor - such as gardens) help reconnect residents living in close proximity? Are there other architectural features that could improve this situation? 

  • Diana Campioni added an answer in Blood Culture:
    Why are MSCs from blood (peripheral and umbillical) typically cultured in a media with a higher content of serum, than MSCs from other tissues?

    In general it seems MSCs from blood is cultured in media with 20% and 30% FBS, compared to MSCs from other tissues (bone marrow, adipose tissue etc.) which is often cultured with 5-15% FBS. 

    Why is that? In what way is PB-MSC or UCB-MSC different and require a higher content of serum?

    Diana Campioni · Universita degli studi di Ferrara

    In the first step of BM-or CB-MSC isolation higher content of serum permit the better survival of hematopoietic cells  that means also a better cytokines and growth factors productions in the co-culture favouring the adherence of MSC. After 15-20 days when the culture is well established it is possible to use different media with minor FBS content.

    Anyway you can use 20-30% of FBS when you are also interested to maintain and to study the survival of the hematopoietic counterpart.

  • How can I upgrade a AS WWTP to use MBBR without much civil investment?

    I currently have an activated sludge (AS) waste water treatment plant (WWTP) on site, and I want to decrease the retention time for the treatment process while improving the results from the plant.

    I am currently designing a disinfection chamber with UV to improve the results, and considering a tertiary filter. But I still need to reduce the retention time because the plant is under-capacity.

    Is it logical to install another tank for MBBR treatment after the clarifiers and before the blending tank? Or should I utilize the biological treatment tank and scrap the AS all together?

    Milind Kulkarni · ITM Group of Institutions

    I feel the option of converting existing aeration tank (bio reactor) as moving bed bio reactor(MBBR) is worth trying. You need to add suitable media. This way the cost of additional civil works will not be required.

  • Benoît Fortin added an answer in Radar:
    Can someone provide me with real datasets to compare and evaluate multiple target tracking methods ?

    I am looking for real datasets to validate and compare mutliple target tracking methods, for example radar positions of multiple airplanes models, positions & velocities of vehicles.

    If multiple models are used to target tracking, it can represent an advantage (for example in airplane application : bombers, fighters, liners....

    Radar is not the only interesting sensor. Datasets provided by other kind of applications would be very useful.

    Benoît Fortin · Université d'Artois

    Dear Hugh and Graham,

    thanks for your answers and the provided link to the interesting paper concerning a joint tracking and classification approach. It can be very helpful to compare your results with mine.

    Graham, concerning your remarks, I will study your papers and a sonar application could also be imagined to validate my methods. Indeed, we build them in a general way and the application areas are multiple. Sonar tracking is an interesting problematic and I will study it in details and I will try to implement my method in this application.

    I will contact you if I have some questions about this kind of data.

    Thank you,


  • Jean-Marc Cavaillon added an answer in Chemotaxis:
    Which chemokines do not induce chemotaxis and extravasation of neutrophils?

    Are there any known cytokines that do not have a major effect on leukocytes. I understand that these molecules are necessary for diapedesis of leukocytes during inflammation, but are there nonfunctional ones? Or are there methods to inhibit the functions of the cytokines without completely denaturing it?

    Jean-Marc Cavaillon · Institut Pasteur

    Most chemokines if not all have chemoattractant properties, but most have other biological properties (histamine release; angiogenic; angiostatic; pyrogen; favoring anorexia; interfering with hematopoiesis, microbicidal (i.e. defensin-like), neuromodulation, inhibiting or favoring with pain...).

    All chemokines are functional, but there are non-functional receptors (so-called decoy receptors : D6 ; DARC ; CCX-CKR).

    There are few chemokines inhibitors : e.g. Antileukinate ; Pepducin. Also some viruses have developed chemokine ligands, which inhibit some chemokines (Myxoma virus, orthopoxvirus, pox virus) or produce some chemokine antagonists (Stealth virus, Marek disease virus, Kaposi’s sarcoma associated virus, Molluscum contagium virus, human herpes virus...)

  • Talaat I. El-Emary added an answer in Acetoacetates:
    Can somebody share with me some papers on how to synthesize 3-acetyl-7-hydroxycoumarin?

    I tried to synthesis the aforementioned compound by reacting 2,4-dihydroxybenzaldehyde and ethyl acetoacetate in the present of piperidine as catalyst. According to the method that I'm using, after being left overnight, yellow solid should be forming. However I did not obtained any solid the next day. Can somebody share another method to synthesis this compound?

    Thank you in advance. 

    Talaat I. El-Emary · Assiut University

    Dear Dal N. l

    You can follow the following paper.


    Good Luck

    Prof. Dr. Talaat El-Emary

  • Sarah Elsharkawy asked a question in Twitter:
    What is the best way to gather a full Twitter dataset for a specific hashtag in a certain period of time?

    I need all tweets containing a specific hashtag in a certain period of time. I need also all retweets and user profiles related to the gathered tweets. Putting into consideration Twitter API Limitations. 

  • How can I charge metal or metal oxide particles negative or positive?


    I'm a student studying nano material. I have a question about (nano)partice charge.

    I want to charge metal(gold, silver, iron whatever...) or metal oxide particles chemically or physically.

    I searched that problem all day but I can't get it solved.

    please let me know

    thank you :)

    Victor Ivanovich Lesin · Russian Academy of Sciences

    You should change pH of media.

  • Why has PCR amplifying 4kb DNA using cDNA as a template failed?

    I used the SMARTer RACE kit from clontech to get the 3' and 5 ends of my target gene. Then I tried to PCR amplify the whole gene. I tried both the platinum Taq High fidelity DNA polymerase and SeqAmp DNA polymerse system but didn't work. The cDNA I am using is the 5'RACE ready cDNA. Primers were designed based on the 5' and 3' UTR, 18bp long and with Tm around 50 degree. I know my target gene has low abundance. So I always add about 400ng cDNA to each reaction. I tried annealing temperature ranging from 42 to 55 degree. Extension at 68 degree for 4-5min. Initial denature at 94 degree for 30sec to 2min. And Ma2+ concentration is 2mM for platinum Taq DNA poymerase and 1mM for SeqAmp DNA polymerase. 

    Can you give me some suggestions on PCR a 4kb product? Thanks.

    Wirote Tuntiwechapikul · Chiang Mai University

    Reverse transcriptase is a DNA polymerase with poor processivity.  If you use poly-T as the primer, most of the cDNAs will lack the 5'-side.  That's why RT-PCR is good for gene expression, but not very good to use as template for the whole gene, and 4-kb cDNA is a very long one.

  • Thomas Dax added an answer in Ecological Economics:
    Is there a seminal paper on environmental and ecological economics that someone could recommend?

    Teaching a class on environmental and ecological economics and want to assign some really good readings on the topic. Basic and introductory elements would be preferred!

    Thomas Dax · Federal Institute for Less Favoured and Mountainous Areas

    in addition to the useful papers already mentioned to give an overview, more recent discussion might be relevant and provide supplementary aspects, e.g. Clive Spash's article "The shallow or the deep ecological economics movement?" in EE 2013, Pages 351–362. see: http://www.sciencedirect.com/science/article/pii/S0921800913001948

  • How to implement ANN (Artificial Neural Network) model in microcontroller?

    I have weights and biases for my network model, training in MATLAB tool. I implemented the network model in MATLAB code and i compared the results with sim() function unfortunately i am getting wrong results.

    Anyone implemented the network on microcontroller?

    Joachim Verhelst · University of Leuven

    Can you specify your question a bit further? Your current statement is quite vague.

    Some usefull additional details would be:

    What microcontroller you are considering, what type of system you want to emulate, and if you want to implement the model in the controller for co-simulation, control or fault detection?

    If you'd like to switch to a specific microcontroller, it could be usefull to investigate the programming languages and toolboxes available for that component.

    Also, try to make sure the code, structure and model order is suitably chosen in Matlab (with acceptable fit in cross-validation), since otherwise you'll be implementing an useless model for your purpose.

  • Xizhang Chen asked a question in Laser Welding:
    International collaboration request?

    Research interest: Robot welding, Laser welding/cladding,Joining of new materials. Proposal,funding application,project and experiments. Send me email through kernel.chen@gmail.com if interested

  • Huibing Wang added an answer in Membranes:
    How do you do your western blot normalization ?


    I'm working on a new project which involve "quantify" an effect on protein levels. As I am working with rat samples I have a lot of samples to pass through Western blot.

    In my previous lab I never had the chance to perform this step so right now I have a lot of questions. I wonder if I can compare different blots and how ?

    And I have to say that for some of my proteins I use different exposition time for the same membrane (I cut the membrane in different pieces) and depending on saturation. I try to be at the maximum signal before any saturation but for some of my protein of interest I can say that it will never be the case (signal too faint). Am I doing right ?

    Should I present my result as ratio of protein of interest on loading control and only then compare them. Or should I compare membrane per membrane and then mix all the results ?

    I don't know if I am being clear...

    Thank you

    Huibing Wang · Chinese Academy of Sciences

    I suggest that you do a BCA quantification before western-blot as gray scale of western-blot result is not so precise and not well repeatable, so a BCA quantification before western and then a  gray scale analysis of may modify the 

  • Has anyone proposed a comprehensive psychological theory of religion that is scientifically verifiable?

    Not counting brain spot theories etc., just psychological, cognitive, or behavior theories.

    Julian Wienert · Universität zu Lübeck

    Dear Steven,
    I attended a keynote once, given by Professor Crystal Park. She is incorporating religious beliefs and spirituality into health (psychological) research. This is absolutely not my field of interest, but maybe she defined or uses a suitable and comprehensive theory.

    Kind regards from Germany


  • What is the easiest method to identify the angular offset of the index (mark) pulse of an incremental encoder and the closest north pole on the rotor?

    Sometimes motor builders don't provide this important piece of information that is critical to Field oriented control of sinusoidal (AC) permanent magnet brushless motors. In this question I assume that the rotor angle is the angle between the direct axis of the rotor magnet and the axis of phase "A". If one could know this offset delta (and whether it leading or lagging the N-pole axis with respect to a given sense of rotation), it is then easy to decide the angle of the stator current vector necessary for FOC.

    Osama Arafa · Electronics Research Institute

    Thanks Gregory too much, your input is really helpful. Just for sharing ideas, we have gone through a different procedure. We have made the counter weight and the car load critically balanced such that the motor sheave could be rotated with hand. Then we applied a steady zero-angle vector from the inverter  (at current saturation limit) thus an assisted-rotor -homing (or alignment to the zero angle) could be done. We dismantled the old encoder, and prepared the new one with a mark on its rotor and housing that corresponds to its zero. Then we tightened the new encoder such that the zero marks on both its members are aligned . Now, the rotor at home position gives a zero angle by the encoder and it works fine

  • Irina Kaygorodova added an answer in MEGA:
    How to deal with this error message {Aligned sequences must be equal lengths (in line 28)} in Mega 6 Phylogenetic analysis ?

    Kindly tell me why I am getting this message in Mega 6 software while constructing a phylogenetic tree. 

    I have created a meg. file having my sequence along with 4 related sequences from genbank. but when I try to open this file in MEGA 6, it says "Aligned sequences must be equal lengths (in line 28). The software is easily opening its "example file named hsp20.meg"

    I have attached an image of the error message, kindly help me. I shall be highly obliged.

    Irina Kaygorodova · Limnological Institute, Irkutsk, Russia

    Look at the message of MEGA - you can see that your sequences have different length - L. donovani has 9 nucleotides in the last line whereas the previous sequence has only 7.


  • K. Karthik added an answer in Bacillus:
    How can I prevent Bacillus spreading?

    A colleague of mine has been having some trouble when plating Bacillus on TSA; some colonies randomly spread over the plate, making it impossible to get an exact count of individual colonies on the plate. Is there a way to prevent such spreading?

    K. Karthik · Indian Veterinary Research Institute

    Increasing the concentration of agar to 2-3% can prevent the spreading which we do for proteus

  • Bellel Nadir added an answer in Schottky Diodes:
    How can I explain very low short current density Jsc in schottky diode ?

    Organic/inorganic schottky diode structure.

    Bellel Nadir · University of Constantine 1

    SEE THIS SITE www.researchgate.net/publictopics.PublicPostFileLoader.html?id...


    Physique des Dispositifs
    C´edric KOENIGUER
    http ://koeniguer.perso.cegetel.net/ifips/ifips.html

  • Does metal ions affect the spectra of HPLC?

    The retention time of the sample (mainly organic acid) is in accordance with standard sample, but the peaks are not as symmetric as standard sample. Maybe, my sample contains some metal ions. Would these metal ions affect the shape of the spectra?

    Subhash C. Tripathi · Department of Atomic Energy

    Dear Mr Xinyan Dai

      I like the innocence of your questions, But please understand. Interference inHPLC means 2 things(1) Where it( metal ions) gets coeluted along with the  target analyte?

    if it is so then find the answer to point (2) below:

    (2) Does the spectra of Interfering metals ion present  overlap with that of targent       ( Organic)  analyte??

    also Remember or try to find out  the rough concentration of  and Extinction coefficient of metal ion( AL) in eluting media.

    Since you suggest presence of "some Al ions" Remember that ( my guess) Al doesnt have significant absorptivity and  even if it sconcentration range of  mg/L or approx 100 ppm, it wont be such a problem.

     I give due weightage to answers given by prof. Joan Vaccaro.

    All the best

  • What is understood, in terms of biosecurity and biosurveillance, by Early Warning Systems?

    My research group and me are inquiring about this question and we want to answer some isues about this topic, in addition to this general question, we want to know:

    -What is understood, exactly, by biosurveillance?
    -What is understood, in terms of biosecurity and biosurveillance, by Early Warning Systems?
    -From the point of view of biosurveillance, scientifics and experts, what is currently the role of citizenship?
    -There are tools, apps, guidelines, etc. whereby citizenship can collaborate or "enact" as alert system?
    -Where can we find documentation about this kind of issues?
    -What is a sentinel site or a sentinel web? and how it works?
    -What is the role of Internet into this new intelligence related with detecting pandemics and acting before it occurs?

    I have some stuff written about it in my blog: http://ebaes.blogspot.com.es/

    Thanks in advance, 


    Enrique Baleriola · Autonomous University of Barcelona

    This night I was thinking about the topic we are interested in, and I would rather know if you agree with the idea that people (lay citizenship) is understand as a new realm of risk (in terms of biosurveillance) due to the "flux" or the movement between boundaries. 

    I say this, because we want to confirm hypothesis of whether people can be "surveilled" and "surveillors" of the bios at the same time during and outbreak, for instance.

  • Rune W Berg asked a question in Model Theory:
    Collision of action potentials: annihilation or penetration?

    In axons, action potentials can move both in ortho-dromic (normal) direction as well as in anti-dromic direction, if stimulated in the right way. But what happens if two action potentials are generated simultaneously, one in the distal axon end and one at the soma, that are moving towards each other to collide? Will they penetrate (move past each other) or annihilate?

    According to classical Hodgkin-Huxley model and theory of neurophysiology they will annihilate due to the in-activation of the sodium conductance. This effect has also given rise to the experimental method called "the collision test", which is used to confirm axon projection from one brain region to another by means of antidromic stimulation. 

    Nevertheless, a recent paper claims that two colliding action potentials will penetrate just as two colliding waves on a sea of water:


    My question: Does anyone know the original literature about collision of action potentials? This must be back in the 1950'ties or 1940'ties. Who did the investigation and what are the publication references?  I have been trying to find the original papers, because I am sure that scientist investigated this back in those days. The only one I could find was this:

    I. Tasaki, Collision of Two Nerve Impulses in the Nerve Fiber, Biochim. Biophys. Acta 3, 494 (1949).



  • Lina Papadimitriou added an answer in iNOS:
    Is there an upregulation of some M2 markers while polarising macrophages to M1 and vice-versa?

    When I try to polarize murine BMDMs to M1, Arg-1 is simultaneously upregulated with other M1 markers. On the other hand, in M2 polarization protocols, iNOS and IL-6 upregulation is seen. Has anyone seen similar reports or results?

    Lina Papadimitriou · Foundation for Research and Technology - Hellas

    Hi Arya. Do you use FBS in your culture medium? I have faced similar problems when I used high concentrations of FBS (up to 10%). FBS contains many cytokines and growth factors (like TGF-b) which can preactivate and polarize immune cells including macrophages. Now I work with 2% FBS and everything seems better.

  • Atul Shinde asked a question in Constructed Wetlands:
    How to design a lab scale model of constructed wetland?

    I need to construct a pilot model of constructed wetland and going implement it in laboratory, how should I design it? Is there any thumb rule to design it?

  • Juerg Kuoni added an answer in Cancer Cell Culture:
    Can hormone-blockade eradicate a prostate cancer cell population?

    hormone blockade is generally followed by a sharp decrease of PSA to unmeasurable levels. This can mean that the cell population secreting PSA is destroyed or that the cell's ability to secrete PSA is blocked. Does anyone know a study showing the response of a prostate cancer cell culture to hormone blockade?

    Juerg Kuoni · heartcheck Zurich

    Basri Cakiroglu: histopathologic changes in what direction? More malignant, less malignant, leading to cell death? Would you please have a reference? Thank you!

  • Rüdiger Grote added an answer in Urban Environment:
    What are the emerging issues for urban environments and ecosystems i.e. potential threats and opportunities that are currently poorly recognized?

    We are having a workshop in Auckland in 2 weeks to consider urban pressures on the horizon.  The challenge is to think of new ideas, or issues poorly studied, rather than the usual problems or exacerbators of the usual problems. Your ideas would be welcome.