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  • Raewyn Billings added an answer in Multiplex PCR:
    Is there a software that can suggest which primer combination should go in a multiplex PCR?

    I have designed 30 oligo pairs and found out that some of them can build dimers. I would like to use a software to help me suggest which of the 30 oligos can be in one pool and which should go into a different pool. Maybe a total of 5 pooling mixes.

    Raewyn Billings · Pathology North

    I have used Mprimer, it worked well for one set of primers.

  • Muhammad Imran added an answer in Business Models:
    Is there any business model available in open literature for low temperature district heating?

    Can someone provide the reference for low-temperature district heating business model? The business model should balance the mutual interests of the company, customers and nation. 

    Muhammad Imran · Korea Institute of Energy Research

    Dear Dr. Zahid H. Ayub, 

    Thank you for the comprehensive reply. I have included the list of the successful district heating projects that are either using the heat pump or low-temperature heat source for district heating in my report. "Drammen Fjernvarme District Heating Project" was one of those projects. It is a great pleasure to know that you were part of that project. It is the world largest heat pump district heating facility after Helsinki District Heating, Finland. The total heating capacity of Helsinki District Heating is 16.8MW and cooling capacity is 18.1MW which uses the Unitop® 50FY heat pump provided by "Friotherm" with the full load capacity of 20MW each. Currently, we have the similar project, utilization of sea water for district heating with the heat pump. I would like to contact you in future regarding our project, specifically related to evaporators and condensers of the heat pump. Thank you so much for your valuable suggestion and time.

    Best Regards


  • Carole Rushton added an answer in Positive Psychology:
    Can you help me with my mixed-methods research dilemma ?

    I am beginning a research project where I conduct 3 to 4 individual interviews (30minutes) with older subjects in nursing homes suffering from depression. In line with positive psychology, we will be discussing difficult moments/periods in their past and exploring the positive qualities/ressources/traits that enabled them to get over these difficult periods. The hypothesis is that these sessions will lower depression and increase positive affect. The scales to measure this are the CES-D depression scale, the Positive and Negative Affect Schedule and Diener's Satisfaction with Life scale. Measures will be taken pre and post intervention and then at 7 weeks to see how well the results were sustained.

    One problem I have is that I suspect that because they are depressed they will have difficulties identifying the positive qualities they had that enabled them to get over the difficulty. I want to avoid orienting the discussions or being the one to point out the qualities they demonstrated : ideally I should only guide them to see these aspects themselves. Does anyone have a recommendation for a good practical qualitative research methods guide that could help me with this aspect of the interviewing ?

    Problem 2 : what do you think of the scales I've chosen ? The goal being to pinpoint that it is the effects of the intervention (i.e. identification of positive traits in past situations of adversity) that lowers depression and increases positive affect.

    Problem 3 : I recognize the biais that the interviews and the rapport created between myself and the participants in this therapeutic context could in and of itself be the factor that lowers depression and raises positive effect. I do not see how to distinguish in the results the effects of the intervention and the therapeutic relationship. Does it seem feasible in a thesis research project to simply identify this biais ?

    I truly would appreciate your help with this. Unfortunately my thesis professor has not been able to give me enough guidance with this dilemma. Any recommendations are welcome !

    Thanks in advance


    Carole Rushton · Griffith University

    Holly, sounds like a really nice project.  Are normative and positive psychology mutually exclusive? I am not a psychologist but maybe what is normative is also positive...whatever positive is? The intervention is the therapeutic relationship. As a community health nurse, it was my relationship with isolated older people that was the therapeutic to them. You/we are the tools of our trade. I wonder if being too reductive can obscure the ways things work relationally i.e. the challenge will be sustaining the 'positive' outcomes of the study through positive relationships.

  • Thomas Wayburn added an answer in Climate Change:
    Is it time we shift emphasis from technological solutions to climate change & focus on the 'Human Dimension'?

    Is it not obvious that nature can heal itself, if only left alone, and it is we humans who need regulation? Many natural parks managers do just that; seal off the area from human interference to let nature heal and recover. It is classified as 'Strict Nature Reserve"by IUCN. Complacency and inaction are not advocated here, as many have misunderstood, but the shifting of focus from technology to the human being. As technology is no match for human greed, isn't introspection & restraining ourselves more relevant than developing more technology, which caused the mess in the first place, by making it easy for a few to consume more? Since technology is only a short term quick fix which fails after a short time, isn't the real problem our addiction to material consumption & our lack of understanding about human nature? Isn't developing more technology sustaining the addiction instead of correcting it, leading to more complex problems later on, needing more complex technological quick fixes like higher drug dosages, more ground troops & equipment, (along with their debilitating side effects) in the future? Isn't this the vicious addiction circle we are trapped in? As researchers, do we merely buy more time with technology OR go to the very root of the problem, the human being?

    A lot of hue and cry is made about climate change and the environment in general. Public and private money is poured into research to study its effects on the environment, sustainability etc. Should we study nature or ourselves?

    " Our studies must begin with our selves and not with the heavens. "-Ouspensky

    Human activities have been found to have a direct correlation to climate change and its impact on the environment(I=P x A x T, the Ehrlich and Holdren equation), in spite of what some complacent sections say to protect their own self interests.

    We hardly know about Human nature. We can scarcely predict human behavior. We need to find out why we think like we do and why we do what we do and why, in spite of all knowledge and wisdom, consume more than what we need, in the form of addictions to consumption and imbalance not only ourselves but also the family, society and environment around us..
    Humanity is directly responsible for all the unnatural imbalances occurring on the planet. Yet we refuse to take responsibility and instead focus on climate change, or fool the public exchequer with a 'breakthrough in renewable energy just around the corner'. We scarcely know what drives human beings. If we had known, all the imbalances around us would have had solutions by now, given the amount of money plowed into finding such solutions. Are we blindly groping in the dark of climate change because we don't know the answers to our own nature?
    Is it not high time we focus on what makes us human, correct our consumptive behavior and leave nature to take care of climate change? Why focus effort on 'externals' when the problem is 'internal'- 'me'?
    Aren't we addicts denying our addiction and blaming everything else but ourselves?

    " We are what we Think.

    All that we are arises with our thoughts.

    With our thoughts, we make the world." - Buddha 

    IMHO, We don't need to save the World. It is enough if we save ourselves from ourselves. The need of the hour is not vain glorious interventions, but self-restraint and self-correction!

    The Mind is the Final frontier.

    Thomas Wayburn ·

    Alastair et al.

    As long as we are striving for scientific accuracy, let me suggest that what we are consuming is NOT energy but availability, that is, energy corrected for entropy – either Gibbs availability (H – ToS) or Helmholtz availability (U – ToS).  When availability is entering or leaving our control volume (system), we use Gibbs availability; when referring to an accumulation within the control volume, we use Helmholtz availability.  These expressions drop right out when we subtract our entropy balance (Second Law) multiplied by the temperature of the environment – whether it be the nearest readily available practically infinite thermal reservoir or deep space – from our energy balance (First Law).  Thus, we have a combined First and Second Laws of Thermodynamics in which balance equations are closed by a “lost work” term that accounts for irreversibilities.

  • Litty Varghese added an answer in Photo:
    Distinction of photo thermal and photo chemical reduction of material?

    Which technique is the best to distinguish between photothermal and photochemical reduction of material?

    Litty Varghese · Swinburne University of Technology

    Thank you. I will have a deeper thinking on it.

  • Hui Fei added an answer in Drug Compounding:
    Which tools can plot inter-hydrogen bonding interactions graph?

    i want to plot total number of inter-molecular H_bond interactions between the drug compounds and target protein like below mentioned link.


    kindly guide me by using which software this plot can draw.

    Hui Fei · Zhejiang University

    hi,sidra , i have used“DISCOVERY STUDIO”to plot the Hbonding betwen residue acids and substrate,maybe it may help you

  • Sudev Naduvath asked a question in Education:
    What are the essential qualities of a good educator?

    What are the essential qualities of a good educator?

  • Marilou Barrios added an answer in RNA Isolation:
    Is the RNA concentration(e.g 200ng/ul) too low for RT-PCR?
    I got the following concentrations of RNA from C6 cells using nanodrop. I added 50ul of nuclease free water before measuring concentration. Are the samples contaminated as 260/280 ratio below 2?
    Marilou Barrios · University of Melbourne

    Thanks everyone. This thread answered all of my questions in mind. I also got a very low RNA yield and was wondering if it will be enough for cDNA synthesis. I used TapeStation to view the quality of my RNA samples. I'm gonna try nanoDrop to know the A260/280 and A/260/230 ratios. I did TrizolLS extraction of my exosome samples and then passed it through miRNEasy kit to isolate the RNA. For some odd reason I saw that my RNA samples contain some contamination. I'm not sure if it's DNA, protein or chloroform? I'm hoping to have a better idea after nanodrop.

  • Tawa Dambe asked a question in Health Policy:
    THe study of health policy. would or may anyone highlight the procedures in proposing a Health Policy?

    Health Policy. Please High light the procedure in proposing a health Policy?

  • Raewyn Billings asked a question in Multiplexing:
    Does anyone know program that will multiplex my primers into pools? I have around 180 primer pairs i need to pool in around 5-7 plex reactions?

    I have tried Mprimer, it works for only 1 gene of primers. I Have primers for 3 other genes and MPrimer wont work on them.

  • Adamu Usman Mohammed added an answer in Arsenic Speciation:
    What is the simplest method to analyse arsenic speciation ?

    Can any one suggest a simple method of analyzing arsenic speciation 

    Adamu Usman Mohammed · Abubakar Tafawa Balewa University

    Thank you very much ma Jie for your contribution, I am grate for the paper attached

  • Magda Toda added an answer in Differential Geometry:
    Is there this book in English "Darboux' Leçons sur la théorie générale des surfaces et les applications géométriques du calcul infinitésimal."?

    Darboux' Leçons sur la théorie générale des surfaces et les applications géométriques du calcul infinitésimal.

    Magda Toda · Texas Tech University

    Interesting - look what others had to say about this :-)


    Best of luck.


  • Suseel Jai Krishnan added an answer in Heat Conduction:
    How do I calculate heat flow through refractory layers?

    I want to design Furnace refractory lining. I know about inside temperature, outside desired temperature and general refractory lining parameters ( e.g, density of different linners, heat conductivity and thickness etc). I need to calculate temperature drop across different refractory layers. Is there any formulation?

  • David Charles Wright-Carr added an answer in H Index:
    What number in the h-index is considered to be a "passing grade" these days by hiring committees?

    Of course this must vary widely among disciplines, institutions, and regions. Does anybody have an example, preferably mentioning these three variables to provide context?

    David Charles Wright-Carr · Universidad de Guanajuato

    Thanks, Daniel and Avishag. Your answers are helping me understand this bizarre new numbers game.

  • Amos Yanda added an answer in Age Groups:
    What are the influences of potts disease in PNG?

    What causes Spinal TB, the age group that are affected, risk factors and its influence.

    Amos Yanda · Divine Word University

    Is there any studies regarding pott's disease & its etiology?

  • Anirudh Kumar Satsangi added an answer in Subjectivity:
    What paper is your best ?

    You rate a certain paper of yours as the best. But your RG peers download your other paper the most, finding the subject and your answer as more attractive. So, what paper is your best ?

    Anirudh Kumar Satsangi · Dayalbagh Educational Institute

    Meditation and Psychoanalysis; Mathematical Formula for Spiritual Quotient and Emotional Quotient as Indicator of Level of Consciousness and Black Holes and Indian Scriptures are among my best papers.

  • Kedar Mandakhalikar added an answer in Biofilms:
    How might I differentiate between planktonic bacteria from biofilm?

    I want to quantify biofilm forming bacteria so I let E coli form a biofilm on silicone catheter for 48hr, then wash the catheter in PBS with vortexing to remove planktonic bacteria. Then I sonicate to extract biofilm and plate the sonication supernatant to get a count. I am not sure though that the count I get is all of the biofilm formed in 48hr or some biofilm was washed off during vortexing.

    On the other hand, if I directly sonicate, then there is a false increase in the count because of planktonic bacteria.

    Is there a way to extract biofilm without losing it or without an interference from planktonic bacteria? Does vortexing disturb biofilm formed on silicon surface? 
    I am grateful for any help regarding these questions. 

    Kedar Mandakhalikar · National University of Singapore

    Thanks Hadeel!

  • Jingwen Zhang added an answer in Glutathione Reductase:
    How can I delete NADPH from cells?

    Hi guys,

    I am studying the mechanism of glutathione reductase (GR) inhibition.

    My drugs can inhibit GR activity but don't affect its protein level. 

    NADPH can reduce the disulfide bridge at GR active site and then enable GR to reduce GSSG to GSH. Therefore, to see whether the reduced form of GR is required for GR inhibition,  I wanna to delete NADPH to prevent reduction of the active site, and see whether my drug still have inhibitory effects on GR.

    However, I can't find an inhibitor for NADPH, or siRNA. There is NADPH oxidase (NOX) available, but NOX may generate ROS which may disturb my experiments.

    Kindly suggest!


    Jingwen Zhang · National University of Singapore

    Dear all,

    Thanks for the kind replies, very appreciated!

    @Roberto and  Daniel, PPP inhibitor is a great idea!! I'd like to try it, but I also concern about its side effects as mentioned by Roberto.

    So I may try  to see drug-enzyme reactions in a non cell-based assay, as suggested by @Martin. I'll do it according to this paper (Mol Biosyst. 2009 Sep;5(9):1013-24). In this system, NADPH can be deleted by just not adding it to the reaction buffer.

    Hopefully I can do this assay in a correct way ^^, because I'm not a chemistry person~ Anyway, thanks again for all the help!


  • Mark Chi Ho Ng added an answer in Quantitative Data Analysis:
    How do I get the Partial Least Squares modelling program?

    want to use it for my some data analysis 

    Mark Chi Ho Ng · Hong Kong Shue Yan University

    SmartPLS 3 can have one month free trial. You can decide to use 2 or 3 after trial.

  • Tee Guidotti added an answer in Vinyl Chloride:
    What is the chemistry of vinyl chloride in fires?

    Vinyl chloride is a pyrolysis (not a combustion) product of poly(vinyl chloride) and may be formed by chlorine reacting with hydrocarbon in fires. PVC generates lots of chlorine as it decomposes in a fire. However, the usual references for chemical composition of fire atmospheres do not report VC concentrations. What is the chemistry, because VC is obviously being liberated from heated PVC?

    Is it being consumed by combustion as quickly as it forms by pyrolysis?

    Is the detection method deficient in studies that fail to report it? (Some methods have problems with two-carbon hydrocarbons.)

    Is the reaction between chlorine and ethene kinetically unfavorable, for some reason?

    I have not been able to find the answers in the references I've checked.

    Tee Guidotti · Occupational + Environmental Health & Medicine

    Yes, I am aware of the paper. I already have that reference in my files and it confirms that VC should be present at detectable levels in fire smoke. I can see how it can be formed by simple addition. However, when the composition of fire smoke is analyzed, it is not reported. I think that VC is rapidly oxidized and it is probably consumed too quickly in the fire to show up. However, can find no reference for this. I would be grateful for more complete documentation of VC in fires, but I guess that Huggett and Levin (1987) is the best we have.

  • Amos Yanda asked a question in Compression:
    Are there any studies regarding the compression of spinal TB?

    Are there any studies regarding the compression of spinal TB?

  • Amos Yanda asked a question in Etiology:
    What are the etiology of the pott's disease & its influence in png?

    what are the causes of spinal TB & its etiology, factors, signs & symptom?

  • Nabeel Ali Bakr asked a question in Mathematics:
    How do you choose between two doctors ... first made 100 surgeries and failed with 10 ... the second made 10 and failed with only 1?

    If we treat the problem mathematically, then 10/100 = 1/10 but if we want to make a decision related to life, what would we choose?

  • Yuan-Yeu Yau added an answer in Information Technology:
    Without the use of modern information technologies to conduct research work possible?

    Dear collegues,thank you very much in advance.

    Yuan-Yeu Yau · Northeastern State University

    Information technology benefits great to modern life in many areas, including researches. But it also has its weakness. These include that people can hack into it to steal valuable research results, personal ID, trade secretes, important data..etc. The security of  this technology need to be improved.

  • Carlos Soto added an answer in Linear Programming:
    How can I ensure graph connectivity using LP or MIP formulation?

    Linear programming (LP)  or mixed integer linear programming(MIP) 

    Carlos Soto · Instituto Tecnológico de Ciudad Madero, (ITCM)

    You can look at the paper "A Survey of Graph Layout Problems", there are defined a wide variety of  linear programming models for graph problems.
    And the paper "Variable neighborhood search for the Vertex Separation Problem" implements an integer programing model for vertex separation problem. In Section 3 you can see the model. In this model the graph is represented as a permutation. The variable yu,vp,q = 1 if there is an edge from u to v. In this paper you can find more information and a extended explanation.

    I hope this can help you.

    PD: Both articles are aviable as pdf in scholar google.

  • Lisa Corcoran added an answer in Immunohistochemical Staining:
    What is the reason for irregular staining of antibody in IHC?

    What is the reason for irregular staining of antibody in IHC? Like in my case, in few animals the Immunohistochemistry was very good with layer specific staining (layer 2/3, layer4 and layer5) ,but in other animals IHC there is irregular staining and not layer specific. What would be the reason for this? In the cytochrome oxidase staining for all the animals I found blood like capillaries making me think that the perfusion is not that good. Is improper perfusion resulted in irregular staining of IHC in few animals? The problem of capillaries is in all the animals. But why only few animals IHC are layer specific and good and why not the same with other animals IHC

    Lisa Corcoran · Vectus Biosystems

    Do the sections dry out when you stain with antibody or between wash steps? Use a humidity chamber fro all steps Fixation thickness may not penetrate down through the tissue the whole way. We have used in situ fixation in the past with a hepranised saline (warm) before hand and then fixed with bouins fixative. The tissue was then removed and placed in more bouins for 4hrs then changed to 70% ethanol. Do you use antigen retrieval? If so check the pH of antigen retrieval solution at the end of the treatment and also look at the use by date of the coated slides. Your sections may not be sitting flat. Also try using a pap pen to surround your tissue. Good luck and hope this helps.

  • Alejandro Figueroa added an answer in Bag-of-Words Model:
    How might I generate a random bag of words model?

    I have a co-occurrence network of words. This network is markedly different from random network (The network properties are statistically different ). In order to further investigate this network, I want to compare it with a bag of word model. What will be the best way to generate such random model which perhaps retains original  number of edges ?

    Alejandro Figueroa · Yahoo! Research Latin America

    What do you want to do?

    bagging features?


  • Lisa Corcoran added an answer in Trizol:
    Is there any way to increase RNA concentration ?

    Hi all,

    I wanted to real time PCR for part of my studies. Past few weeks i am trying to isolate RNA from my animal (aquatic animal). For each time i can get around 100 micrograms of rna per ml. Is that enough to do cDNA synthesis? My protocol is as follows

    50 animals were homogenized in 750 microlitre of trizol

    chloroform 1/5 volume of trizol was added and incubated in rt for 5 min

    centrifuged at 12000 rpm for 15 min

    to the supernatant isopropanol 2/3 volume of trizol was added

    centrifuged at 12000 rpm for 10 min

    to the pellet 500 microlitre of 70% ethanol was added

    centrifuged at 12000 rpm for 10 min

    pellet was air dried and dissolved in 12 microlitre of RNase free water

    sample was heated to 70 C for 5 min and stored at -80 C

    Lisa Corcoran · Vectus Biosystems

    Thanks Murugadas

  • Paul Milham added an answer in Soil Chemistry:
    How we can perform soil bio-availability test in plants under metal stress despite in presence of its chelated, bound or any other form?

    Working on effect of Arsenic stress in plants.

    Paul Milham · University of Western Sydney

    Hello Deepak,

    Please refine your question.  It is unclear whether you want to know bioavailability of plant As to humans eating the plants or you are asking something else.

    Kind regards,Paul.

  • Usama Al-sari added an answer in Regression Analysis:
    How might I deal with suppressions in multi-variable adjusted model (regression analysis)?

    Suppressions can be defined as “a variable which increases the predictive validity of another variable (or set of variables) by its inclusion in a regression equation,” a suppression effect would be present when the direct and indirect effects of an independent variable on a dependent variable have opposite signs.

    I run a logistic regression with number of selected confounders, all these confounders are important to include in model (some confounders are statistically important and others are important from the medical point of view). I got a situation in which the relationship between my independent variable and a dependent variable (adjusted OR) becomes larger from the unadjusted one. By analyze each confounder alone, I found that number of these confounders act as suppressions.

    The question now, how  should we deal with this result? Should we accept the result as it? Or maybe better to exclude the suppressions in my model?

    Thanks all

    Usama Al-sari · University of Bristol

    Thanks all for these valuable replies

    I did a lot reading about this topic, however, I cant find a direct answer for my question. In my data (observational study), the unadjusted relation between my IV and DV is positive with significant P value, by adjusting to confounders the relation still positive (sig P value) but with higher OR. I believe that all the included confounders are important and exclude any one may lead to obvious bias.

    For example: My IV (memory) and the DV (fracture), alcohol one of these confounders that acts as suppression, I believe that such confounder is important to include from the medical point of view even if alcohol not statistically related with the memory or fracture.