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  • Pande Gde Sasmita J. added an answer in Aquaculture:
    Between Aeromonas salmonicida and A. hydrophila which one is more virulent on Perca fluviatilis ?
    I want more articles on that topic.
    Pande Gde Sasmita J. · Ghent University

    FYI, in A. hyrophila and A. salmonicida virulence point of view, maybe you can check also the paper by Natrah et al, 2012, Vet Microbiol 159: 77-82

  • Kathy Sias added an answer in Likert Scale:
    How can I account for missing data on an 18 Item Scale?

     My Likert scale is missing data (Skipped Questions). If only 1 - 2 variable items are missing, can I still use the remaining data for that case to reach a final score (by weighting?, Mean? etc)

    Kathy Sias · Florida International University

    Todd Little at TTU covers this - it is in his area of expertise.  He is on research gate and you might be able to see his articles there.  He has also recently published a book Longitudinal SEM.  If you are still stuck next summer, he teaches a STATS Camp and addresses this in his intro to SEM class.  

  • John S Wishnok added an answer in Helium:
    What is the optimal value of the gas pressure in the mass-spectrometer?

    What, in your opinion, is the optimal value of the gas pressure in the mass spectrometric analyzer of helium leak detector in terms of increasing the sensitivity of measurements?

    1. The ion current increases at relatively high gas pressure in the analyzer chamber. The output signal and the sensitivity of the device rise in this case.
    2. On the other hand, the ion mean free path is reduced when the pressure increases. The probability of ions recombination grows.

    Can we analytically derive the optimal value of the gas pressure in the mass spectrometer in order to achieve high sensitivity?

    John S Wishnok · Massachusetts Institute of Technology

    These approaches are always fascinating - and fun - but there are usually unanticipated realities, so it's probably more efficient in the long run to determine the optimal parameters by experiment rather than trying to calculate them.  (You'd have to do that anyway in order to know if your calculations worked.)

  • Joanna Hammond added an answer in Lymphoma:
    Does anyone have any information on outcomes for a patient with no extra nodal or bone marrow involvement?

    Rectal Mantle Cell Lymphoma. Treatments or watch and wait?

    Joanna Hammond · University of Florida

    Negative bone marrow,negative PET scan,negative LDH,all other labs normal.Disease limited to the rectal mucosa and mucosa of ileocecal area.Pt asymptomatic 1 year since initial diagnosis.Pt opts not to treat but wait and watch,and follow up in 1 year for further testing.Any thoughts?

  • What are the prerequisites of capacity building programs in professional communication?
    I am doing research in developing capacity building programs for professional communication. After a literature survey I am able to find only capacity building programs in vocational skills. Can anyone help me with the prerequisites of capacity building programs in soft skills?
    Indira Nair · Carnegie Mellon University

    The work of Professors Suguru Ishizaki , David Kaufer , Baruch Fischhoff and others at Carnegie Mellon may be useful for various facts of this:




  • Mike R Clark added an answer in Hybridoma:
    Does anyone know why a hybridoma culture turn red and not yellow?

    I have a IgG secreting hybridoma. Unexpectly, when the cell number increase, the culture turn red and the cells are not happy. Any suggestions?

    Mike R Clark · University of Cambridge

    Hi Linda, yes of course if all the cultures in an incubator are turning purple it can be a sign of  low CO2 in the incubator. However I think in this case it sounds like a more specific phenomena associated with only some hybridoma clones and not others, even when they're being cultured in the same incubator and in the same media and conditions. That was certainly my experience in the past. If the cells are breaking down glutamine or other amino acids as a principle source of energy, then they may be producing some ammonia or other basic metabolites, which means the media doesn't acidify and turn yellow as expected.

  • Indira Nair added an answer in Software Engineering:
    What are the latest developments in green software engineering and sustainable software engineering?

    Recent research in green and sustainable software engineering.

    Indira Nair · Carnegie Mellon University

    some possibly useful discussions:






  • Jagpreet Kaur Gill asked a question in Encapsulation:
    Sol gel encapsulation

    Hey, i am trying to see the effect of various matrices on encapsulation of my enzyme. For a start, i am doing it with BSA and i tried the method described by Mohidem and Mat (2012). The problem is when i finish sonicating TEOS with water and HCL i see 2 phases, one clear at the bottom and white gel like at the top. I am not sure if this is normal, after that when i add my protein with the buffer, it doesnt gell in 5 minutes (as described by the paper). I am not sure where iam going wrong, what i do see is that after addition of the buffer the white layer is on the top and the clear at the bottom. and the gel doesnt form its still runny in consistency. Please help.

  • Dieter Schneider added an answer in Theology:
    Can someone insert a comment about the Spirit’s work in activating conscience, particularly among the unevangelized people?
    Does God intervene or reveal Christ miraculously to the unevangelised in all cases? How much can one know and believe without hearing the gospel? What is the efficacy of implicit faith towards salvation?

    John Calvin Institutes springs to mind - unsurpassed!

  • Aliasghar Abbasi asked a question in Foresight:
    How do we generate scenarios using Backcasting method?

    In the field of foresight, we use backcasting to generate scenarios or only identify the best path?

  • Does somebody know this plant?

    Please help me, Thanks

    Jiří Danihelka · Masaryk University

    Euphorbia marginata!

  • James Matthews added an answer in Small Molecules:
    Combination treatment target identification

    I've recently conducted/validated a small molecule screen looking for synergy between an RTK inhibitor and a panel of small molecules. I have two strong hits that appear to be targeting the same thing, but there is no immediate clear mechanism between these two compounds and the RTK. Are there any ideas for identifying the mechanism of synergy without individually analyzing each pathway downstream of the RTK?

    James Matthews · Victoria University of Wellington

    What was your synergy measurement? Cell death? Pathway activation?

    The hit compounds might not target the RTK pathway, but the likelihood of this is determined by how you have measured synergy.

  • Andrea Zupunski added an answer in microRNA:
    Which are the best programs for microRNA target prediction?

    So far I have tried TargetScan and PicTAr, but I would like to compare results with other programs.

    Andrea Zupunski · Medical University of Graz

    Thank you for suggestions! I will try it out.

    Best :)

  • Ahmad Zafari added an answer in Plastics:
    Can twinning result in strain hardening exponent value more than "1"? If so , why?

    Few fcc materials exhibits dual slope plastic deformation, one due to slip and other due to twin or twin formation. Why it results in n>1?

    Ahmad Zafari · University of Melbourne

    Twining plays a significant role in changing texture, since it leads to atomic planes rotation. So, depends on the texture strain hardening behavior of the material your are arguing about will be different.

  • How can I get the JCPDS index cards of ZnS Quantum dots and CdS quantum dots?

    X-ray diffraction of CdS QD and ZnS QD

    Edward Andrew Payzant · Oak Ridge National Laboratory

    @Jolly Antony: you need access to a licensed ICDD database to get these entries, or you can contact ICDD directly. If you are simply looking for structures (CIF files) and want to try a free/open database, you can easily get the results you are looking for at www.crystallography.net   Another good crystal structure database is the ICSD.

    @Uma Maheswara Rao Seelam: You can only get these if your XRD software includes a licensed copy of the ICDD database. Without the database, MDI's Jade for example cannot access or search/match such database entries.

    An interesting point is that the two previously answers are different! There are many entries for the same compounds and one must be careful that the selected one is appropriate.

  • Max Perez added an answer in Waves:
    What is the fundamental difference between modulation instability(MI) and Four Wave Mixing (FWM)?

    The standard text books say that MI and FWM are the different descriptions of the same phenomenon. These say that the MI is the temporal description of the breaking of a CW into pulses. The same thing when viewed in frequency domain manifests itself in the generation of symmetric sidebands around the pump and this is called FWM. But I have doubts regarding that when multiple FWM process is described, why the MI and FWM are treated differently?

    Max Perez · Instituto Potosino de Investigación Científica y Tecnológica

    In my opinion, the MI is generated by a pulse which propagates with high intensity and the pulse is compressed, which causes the generated FWM.

  • Malek Amiali added an answer in Lyophilization:
    Does anyone know anything about the lyophilization (Freeze-Drying) of fruit juices?

    I currently work on lyophilization of fruit juices, but I saw that the final product is sticky and it cannot be converted into powder. Do you think that several agents are needed for this process (such as maltodextrin)???

    Malek Amiali · École Nationale Supérieure Agronomique

    What is the temperature of freezing that you are using, it must between -70 to -80C for about 24-48h depending of the volume of the fruits or sample,,,

  • Koen De Winter added an answer in Digital Imaging:
    How can I find the surface area of an uneven closed 2D image?

    The image is drawn on paper and at times a digital image, how to find out the surface area?

    Koen De Winter · Université du Québec à Montréal

    I realize that you would prefer to do this digitally but one of the simple ways is to make a copy and cut it out and compare the weight of it with the weight of one square dm of the same paper..

  • 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

    Francesca: As Andrea and Barry and Stephen Anderson have noted (did you read the article?), the Golden Rule is merely one humanly-created framework amongst many for describing the dynamics involved in ethical/moral interactions among some social groups. There is nothing "Golden" or objective about it, despite its colorful label. We could just as well analyze and describe  moral dynamics of societies in terms of reciprocation, social justice, capitalism, socialism, sacrifice, duty, group survival, etc.

    None of these approaches is particularly better than the others and none would completely subsume the others. All such approaches are conceptual artifacts and thus not externally objective. They are also subjective and arbitrary in terms of how they are measured when applied to real-life situations. So I am not sure where you are going with the term...?? Perhaps you might transpose this vague, rather colloquial term to a more academic term.

    No, I did not actually first bring up gender-related issues of maleness, nor did I bring up the issue of feminism. I merely pointed out that you had yet to demonstrate that any criticism of your scientific reasoning was suspect because the criticism and/or those who made the criticism were part of or representative of some alleged male-oriented Western scientific view.

    It seems that you deny making gender-related comments or to clarify your statements about "Men", and their supposed lack of ethics, their arrogance, and their insensitivity to Life and Reality in comparison with women. 7 days ago in the same post you stated that:

    "Dear Barry, Larry and Filippo, I am speechless about your Arrogance, which is completely unethical...I find the masculine Side here very arrogant, which is an Attitude typically associated to the so called Western Science, if not even to the so called Western World...Life Experience and the feminine Life Experience related to, so called Fatherhood and Motherhood, which maked Women, Mothers, definitely more sensitive, about Life and its whole Reality, than Men"

    These are really scathing remarks against particular men in this forum, about men and fathers in general, and even about the alleged masculinity of Western science and the entire Western World!  Certainly it appears to me that your objection to the comments made by other posters has a lot to do with the fact that they are males.

    I did not call you a feminist. It seems to me that your gender-related attacks are unjustified. I am wondering what exactly you meant by such remarks. Are you suggesting that the Western scientific view is myopic or biased, or that such prejudice has led to unfair criticism of your own claims, e.g. that the heart has a bundle of nerves that provides a center of awareness and moral goodness?

    What specific remarks, exactly, were made by men, as you have obviously stated, that were so insensitive, unethical, and arrogant? And, most importantly, on what basis do you think that these remarks were made because the person or persons or Western scientific community who spoke them were male or had "masculine" characteristics?

  • What precaution should be taken when using ion-selective electrodes?

    Recently several ion-selective electrodes, such as those for NH4, NO3, Cl, F. K, Ca, etc, are becoming available. If I understand it correctly, these electrodes measure ion activity, meaning ionic strength of the solution and ion pairing or complexing would effect the reading. Are these electrodes really measuring free ions? and how can we keep the ionic strength of the solution constant (easily and quickly), yet avoiding ion pairing or complexing?

  • How does social networking sites effect consumer decision making process?
    Consumer decision making process often get changed due to various factors .
    Kenneth C. Adiele · Centre for marketing management and Entrepreneurial research (CMMER.)

    The importance of social  networking sites in influencing consumer decisions cannot be over emphasized. Today, due to the Internet the world has become a global village. Through social networks especially the Facebook  friends, relatives and colleagues can  post and advertise their products and services on line specifying the product's features and advantages.This advertently could make  a prospect to reconsider  his earlier decision.More so, we must  not fail to recognize peers influence in decision making. This most time can be facilitated through the social networks. for instance the purchase of mobile phones and even IPads  and Tablets can be influenced by  one's social and political class.Therefore, it is expected that marketing organizations should maximize the advantages offered by the social networks to increase their sales and level of business viability.

  • David Spector added an answer in Visual Perception:
    What is the relationship between visual perception, stress and anxiety?

    What is the relationship between visual perception and stress, anxiety? What is the mechanism visual perception causes the these effects?

    David Spector · Natural Stress Relief, Inc.

    Glenda, What is the antecedent of 'they' in "especially so if they are an anxious male"? It's ambiguous.

  • How does exercise build bone through stimulation of mesenchymal stem cells?
    Lab studies show how MSC respond to the dynamic physical environment.
    Janet Rubin · University of North Carolina at Chapel Hill


  • In the Big-M Method (Linear Programming), how big should M Be?

    Assume that you have the LP problem: Max z = c'x - M Sum[ y_i ] 

    subject to Ax + y = b, b > 0, x > 0, y>0.

    Assume that y is a vector of artificial variables. What is the smallest M to guarantee that, if the problem has an optimal solution, all y's are non-basic variables in the optimal solution?

    Clearly, one does not want to use an arbitrarily large value for M because of rounding errors.

    Paul R. Yarnold · Optimal Data Analysis LLC

    Hi, Noel,

    Thank you for your reply.

    Fortunately, as I see things, you and I are in complete agreement.

    The problem you describe, and the problem that I describe, are identical. What you call "smallest values" is what Rob and I call "lower bounds".

    This article sets M to its smallest values: http://odajournal.com/2013/09/19/two-group-multioda-a-mixed-integer-linear-programming-solution-with-bounded-m/ 

    Copies of the article are also available from Research Gate, and from:  http://ODAJournal.com 

  • What are the standard radiological exams done before shoulder replacement?
    X-rays only, CT, MRI?
    Thomas Adejoh · Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria

    As  long  as  surgery  is  contemplated,  plain  X-Ray  is  not  adequate. Aside  bones,  muscles,  tendons  and  ligaments  must  be  put  into  consideration. X-Ray  definitely,  cannot  give  better  resolution  than  CT  and  MRI  in  these.

  • How to confirm whether a cell line is MCF7??

    I am working with a cancerous cell line and i want to confirm whether it is MCF7.  Is there any method to do it?? Is there any biological marker which i can look for conformation?

    Mercedes Bermudez · Universidad Nacional Autónoma de México

    I agree, if you want to be absolutely sure it is better a snp signature.

  • Why are specific elements, especially alkali atoms like Sodium being used in Bose-Einstein condensates?

    Despite my attempts to find an answer to this question in various papers,the problem remains unanswered to me. They just cite we use this atoms but never to mention why!

  • Catalina Mira added an answer in Molecular Cloning:
    Has anyone ever placed a His tag between two fusion proteins and got great purification?
    I am designing a new construct and have always had the his tag on the C-terminus, I as I think this leads to the best expression. However on new construct I have a fusion protein added to increase solubility. I have designed it as M-6histag-SolubleProtein-Thrombin-AggregationProne protein. I was wondering if anyone has had the 6-his tag between the proteins in their fusion design and still had excellent purification. I would like to use:
    Any thoughts?
    Catalina Mira · Texas A&M University

    I am trying to make a construct with the His tag placed at the C terminus right after the MBP, in this way:  Aggregation protein_enterokinase cleaving site_MBP_6X His tag

      Is this a good strategy?

  • Fernando Gonzalez Leiva asked a question in Hydrology:
    What is the difference between prediction and forecasting in hydrology?

    Forecasting and Prediction