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  • What is your experience with degrowth and the critique of growth/development?

    I have just been to a conference on degrowth (this one: http://leipzig.degrowth.org/en/) - and left somewhat confused. On the one hand, degrowth is presented as an academic approach with well-known researchers such as Joan Martínez-Alier or Hartmut Rosa defending it. On the other, those guys understand themselves as a social movement with political demands (to reduce growth, to start a transition and so on). While degrowth does relate to my own research (on the concept of Good Life, Buen Vivir or Sumak Kawsay), it seems to be a discourse that tries to integrate everything (just like a social movement would do) - at the same time, the theoretic "core" of degrowth appears quite limited, reduced to certain economic and philosophic ideas.

    What is your experience with degrowth? Does your research relate to it, do you participate in the development of this discourse/approach?

    Terry Leahy · University of Newcastle

    De-growth must be seen as part of a more general approach to the current predicament. I have been calling this approach "radical reformism". It aims to maintain key aspects of the capitalist economy (wage labour, a lot of private ownership of the means of production, the market) while adapting this drastically to the requirements of a zero growth economy. The aim is to arrive at a transition without provoking a violent response from the capitalist class and without the necessity of a revolution. For an extended discussion of some of the problems of this approach see: The New Environmentalism and its Critics at www.gifteconomy.org.au

  • Shivraj Yeole added an answer in CATIA:
    Is it possible to model a human skull in CATIA?

    If yes, what is the procedure of modeling? If not, which softwares can be used for doing so?

    Shivraj Yeole · VNR Vignana Jyothi Institute of Engineering & Technology

    Thanks @Volodymyr Mavrych Sir

    Is it possible to do direct modeling or reverse enegineering in these softwares?

  • Holger Wille added an answer in Scrapie:
    Is anyone acquainted with axon degeneration in Prion related diseases or any other neurodegenerative diseases in Vitro?

    In my lab we working on Prp scrapie 106-126 amino acid sequence.

    Holger Wille · University of Alberta

    The prion protein peptide 106-126 is often used for in vitro toxicity assays, but it is only a rough approximation to the real PrPSc and what happens with this much larger protein. There are a lot of papers published with PrP106-126, they would be a good starting point.

  • How chattering could be eliminated in second order sliding mode control by taking sliding surface having relative degree two?

    higher order sliding mode control

  • Shann S Yu added an answer in Nanoparticles:
    RGD or DGR, which one can bind intergrin?

    Hi everyone, recently I have been trying to conjugate the RGD peptides onto my nanoparticle in order to target the intergrin. But when I was to use EDC/NHS to react with the N terminal of the RGD, I am not sure whether to buy GGGRGD or GGGDGR (G is my N terminal and would react with COOH -containing ligands already  bound to my NPs) Should I buy GGGRGD or the other instead?

    Thanks for answering.

    P.S the GGG sequence acts as spacer.

    Shann S Yu · École Polytechnique Fédérale de Lausanne

    To answer your question, you will need to buy GGGRGD or RGD. You can consider getting GGGDGR as a negative 'scrambled' control peptide which should not bind your cell types of choice.

    I will also add that a major problem of your strategy is that using EDC/NHS will crosslink any NH2 groups you have with existing COOH. Since "D" in RGD is aspartic acid, you risk the chance that you will create polymers of GGGRGD or RGD. Therefore, make sure you do a two step reaction:

    1. EDC + NHS + nanoparticles with COOH groups. Purify with Sephadex column to remove side products and unreacted stuff.
    2. Immediately add GGGRGD or RGD peptide .

  • Holger Wille added an answer in Protein Extraction:
    What is the difference between SDS and sarkosyl?


    I am trying to understand the difference between SDS and sarkosyl detergents in protein extraction/fractionation. I use sarkosyl (1%) to separate soluble and insoluble protein fractions. In an experiment where protein extraction was performed under non-denaturing conditions (i.e without SDS in the extraction buffer) I am able to detect dimers and trimers of my protein of interest which are resistant to the 0.1 % SDS of the SDS-PAGE. These oligomers appear either in the soluble and insoluble protein fraction and the only explanation that I can give is that these dimers are partly resistant to the concentration of sarkosyl used but continue to be resistant to SDS (0.1%), since they continue to appear in the soluble fraction (supposedly denatured by 1% sarkosyl but not ot 0.1% SDS?). This only makes sense if sarkosyl is less strong than SDS. I can't find any good reference comparing both detergents and the function of sarkosyl in protein fractionation. can someone shed some light on this subject?

    Holger Wille · University of Alberta

    SDS clearly is the stronger detergent, since it is commonly used to denature proteins prior to gel electrophoresis.

    Sarkosyl is also a strong detergent and can denature many proteins, but leaves others unchanged.

    If you use 1% sarkosyl and 0.1% SDS that creates a big difference as well. Your sample could easily bind a lot of the SDS, effectively dropping the concentration below the CMC and hence removing all SDS micelles. With 1% sarkosyl this wouldn't happen so quickly. Something to keep in mind.

  • Do probiotics improve your reproductive health and reduce your age of puberty?

    Our observations on mice and poultry birds reveals that Axone (fermented soybean) reduces age of sexual maturity, increases reproductive efficiency and harmonize humoral immunity.

    Marie-Chantal Canivenc-Lavier · French National Institute for Agricultural Research

    I think that the effect of fermented soybean  is due to phytoestrogens present in soy, namely oisoflavones : Genistein exposure (low doses)  during pregnancy also increase the litter size and reduce the age of puberty in rodent s.  Isoflavones are also antiinflamatory molecules. Genistein and daidzeine are the major isoflavones of soy, but daidzeine is  metabolized in equol, a strong estrognic chemical,  by intestinal microorganisms, but only 33% - 50% of human population can excrete equol. But, the specific bacterial species in the colon involved in the production of equol are yet to be discovered to lmy knowledge.

  • Timna Garnett added an answer in Streams:
    What hardware equipment can you recommend for capturing and streaming audio and video from lectures (microphones, webcams, streaming devices)?

    We plan to record and stream video from lectures (room for 20 students, one teacher with notebook connected to data projector). Can you recommend hardware for capturing voice of teacher and students and video of teacher and image from data projector? We do not need to record teacher and signal from data projector separately. Do you have experience with special hardware for capturing and streaming of lectures?

    Timna Garnett · Flinders University

    I recommend the Yeti Blue microphone which can pick up multiple directions of audio (lecturer and students). 

    Video is harder. For some a simple HD webcam is useful, but wont suit everyone's space.

    Streaming lectures usually requires software that has been provided by the university (like Echo 360). Of course there are other tools like Google Hangouts which can stream video of lecturer or screen and webinar/virtual classroom programs which stream both (Adobe Connect). 

  • 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

    Scott: I noted that animals " "are used to establish and maintain dominance relationships, to discourage parasites and cheats, to discipline offspring, and to maintain cooperative behavior." You replied that humans should strive to be better than animals as if you did not look at these qualities...what is so wrong with discouraging cheats and disciplining children?

    I said nothing in my post that would indicate that I was suggesting that humans adopt the morals of animals...but indeed, in many cases that would be a step forward. (It is a bit of a false assumption that animals are basically selfish and humans are not, anyway, as if religion were all about our needing to overcome our selfish, animalistic nature) .

    In any case, my point was that there if research beauty and truth as largely being products of evolution for purpose, we will certainly need to note the homologues between primates in general, and that of earlier hominids and modern homo sapiens. I presume this is a reasonably appropriate way to do research.

  • Jonathan Coulter added an answer in LNCaP cells:
    How can I make my LNCaP cells survive?

    I am growing LNCaP cells now but it seems like they are sick.

    After I thawed a cell stock, I only did two subcultures, and they look sick. They have many black dots around the cell and RPMI badge is dirty. I don't think my media is contaminated as other cells I grow with the same RPMI look fine. This problem consistently occurred and my cells eventually die by clumping. It keeps on making ugly clumps and the cell becomes a bit skinny. I tried to subculture the cell after the media change but they couldn't adhere to the plate.

    One thing I am suspecting is that I might be resuspending the cell more than enough? But again I have been doing the experiments with LNCaP before and it was all fine. But now it is being a big problem and I cannot do anything with it.

    Can anyone please help me?

    p.s. I always leave the cell with a high density as they grow the best in that condition.

    Jonathan Coulter · Johns Hopkins University

    Hi Suzy,

    One way to test whether the "black dots" are a problem is to take some of your medium and add it to a sterile cell culture dish. Simply incubate it alongside your other cells in the incubator to see if anything grows. If not, it is most likely cellular debris, as others have mentioned. I have noticed this in my LNCaP cultures as well, and it does not seem to be problematic.

    One concern could be that keeping them at high density can affect their growth and expression of genes. I recommend not letting them become too confluent, which can affect viability and growth rate.

    Best of luck!

  • Rashad Abdul-Ghani added an answer in Regulations:
    Should academic promotions have a minimum time requirement?

    Full-time academic staff is eligible for promotion if they fulfill all eligibility requirements for promotion. Promotion regulations differ from a university to another. What is the time requirement in your university? What is your opinion about the minimum time requirement?

    Rashad Abdul-Ghani · Sana'a University

    Thank you Prof. Mahfuz. You tackled an important problem in our institutions. In my university, to be promoted from assistant to associate professor, the least required interval is four years. Sometimes, one can publish the required number of papers within a short time, but have to wait until he/she passed the stated interval. I think our universities should change their policies to encourage competitive achievements.

    Kind regards,


  • Remi Cornwall added an answer in MATLAB:
    Does anyone share a simple script using Keithley 2400 with Matlab?

    Hi I'm trying to do a simple script that measures current vs time for a fixed voltage using a Keithley 2400. Does anyone have a simple script they could share on how to do this? So far I am able to connect to the Keithley and set the voltage, but am having difficulties in recording measurements.

    cheers, Rob

  • My S. cerevisiae conditional deletion mutant is dead on FOA but still alive on glucose where it should be dead too! Any idea?

    Hi there,

    I have cloned an essential Sc gene under GAL1 promoter control on a URA3 plasmid (2µ) to generate the conditional genomic deleted strain. As expected, the deleted strain is dead on GAL+ FOA, but it's alive on glucose even after several restreaks! I was wondering about GAL1 promoter leakage on glucose. But I can't see any protein by WB on glucose though (the plasmidic gene encodes for a myc-tagged protein)... Any idea or similar experience? Thanks.

    Dominique Liger · Université Paris-Sud 11

    Thanks for more comments!

    Christoper, I don't have anything growing on FOA which means the presence of the plasmid is essential (ie. there is no suppressor mutation).

    Evelyn, the GAL1 promoter comes from a commercial plasmid which I suppose correct and yes I've made the PCR control you mentioned.

  • What ways do you recommend to evaluate the economical justification of a future renewable energy project?

    I wanted to justify dairy farmers to establish a bio-gas digester in an inside nutrient cycling (INC) system?

    Paria Sefeedpari · University of Tehran

    Dear Susantha Jayasundara,

    I found your information very helpful and constructive. I ask for your further assistance on this subject.

    Great thanks!

  • Dorian Aur added an answer in Intelligence:
    Where is the intelligence in AI?

    Like many others, I am very enthusiastic about artificial intelligence, but the more I studied the AI, the less intelligence I found in it. What I found was classification, pattern recognition, and regression. Is there any hope for real AI to be developed in the future? Is it still correct to call AI AI?

    Dorian Aur · Stanford University

    Excellent, subtle question.  In fact it can be   extended to bio-inspired techniques , Natural  intelligence seems to be  differently generated , different computational principles

  • Ian Eagleson added an answer in Qualia:
    What role has anticipation in consciousness?

    Philosophers says the brain is an anticipation machine. I miss this statement in the present discussions of consciousness on RG. Is there any interrelation of consciousness, Qualia and anticipation?

    Ian Eagleson · Delaware County Community College


    You hit on a crucial point. Our experiences are, we presume, to a great degree qualitatively the same between persons. However, each person has his own numerically distinct experience. (To share this numerically distinct experience would constitute a phenomenon of self-disintegration or something like that. For you to share my numerically distinct experiences would be for you to BE, at least in part, me.)  

    To address your Inuit example, the qualia proponent will say that every color sensation is or contains a quale, and that this is true no matter how finely or crudely articulated one's color categories are. The sensation of pain, of course, is the standard case of last resort for the qualia proponent. Few believe in powers of empathy so acute that someone could literally feel another's pain. Perhaps we might image someone who claims to be an actual empath. "I feel his pain," he says. We respond: No. You have your own pain; he has his. What you are claiming is that your pain is qualitatively identical to his. (And what we would ask is, how do you know that?  If the answer boils down to: well my pain receptors are firing in a like manner, the qualia proponent simply says THAT is not the quale, i.e.that is not the pain.)

  • How do I measure allele frequency in a population?

       I have two different alleles and they have small differences (usually differ in 3 to 20 bp, the largest difference<150 bp). We want to measure their frequency in a population(500-3000 individuals), and we have considered several ideas, such as sequencing them one by one, or using HRM(High-Resolution Melting) to distinguish them. Do you have any idea how to measure it in a  fast way?

    Younes El Goumi · Université Hassan 1er

    Hi Zhao,

    As you work on TALEN you must do a sequencing to give credibility to your work, sequencing can gives you more details. In my opinion

    good luck 

  • Michael Palmer added an answer in Magnesium:
    Does anyone know of a technique similar to microCT that can distinguish isotopes of the same element?

    What technique could one use to create a 3 dimensional image/composition analysis of a material that is made of two isotopes of the same element? For instance, if I make a disc of magnesium, and then coat it with a thin layer of a magnesium isoptope, what technique/instrument could I use to tell me the dimensions/volume/area/thickness of the isotope layer, and could also render an image that differentiates the two? The only thing I have found is neutron scattering (XRD for isotopes), but I want a volumetric analysis....

    Michael Palmer · University of Texas at Arlington

    Thank you everyone! I am looking at your suggestions now.

  • Jan Martinek added an answer in Macrophage:
    What are the functions of macro-phage M2a, M2b and M2c?

    Could anyone help me to find out  the functions of macro-phage M2a, M2b and M2c? I know the function of M1, but for M2 it seems more complicated than M1. I have found some papers list the M2 (a,b,c) functions, but it is vague and unclear. One of the papers is "TRENDS in Immunology Vol.25 No.12 December 2004."

    Jan Martinek · Baylor University


    As others already mentioned the M1/M2 paradigm is not complete, but also the M2 a, b and c groups can be quite confusing in the literature. A group of well known research in the field are trying to change and update this macrophage nomenclature. You can check it in this paper....

  • How can you model evaporation with heat generation from wall and gas flow at the inlet over the water?

    Hi, I am trying to model evaporation of water with heater and there will be inert gas flowing from the inlet. What model is to be used for this type of situation? Is anyone dealing with same type of evaporation problem?

    Hasibul Alam · University of Nevada, Reno

    Hi Roland,

    I am using fluent's condensation-evaporation model for doing this. My main problem is the air-water surface boundary condition. Do I have to declare the surface as interface? or pressure outlet? and another thing is, the water will be evaporating with time and the air-water surface will be moving down as the amount of water will be reducing and volume of vapor will be increasing. So how can I define that motion of air-water surface or boundary?

  • Denis Pinha asked a question in Microsoft Project:
    What is the most common used tool for practical project scheduling with resource constrained?

    Primavera and Microsoft Project software are well known and used in practical applications. However, when resources are scarce and shared along different activities, to level resources becomes cumbersome. In that situation what is the best commercial tool?

  • M.s. Boucherit added an answer in Transformers:
    Can we use auto transformers instead of field rheostats to control field current in DC motors?

    If not, why?

    M.s. Boucherit · National Polytechnic School of Algiers

    It is impossible to use an autotranformer.

    The DC machine uses a Direct Current, but the auto transfomer (like the transformer) provides AC power.

    To control DC motors we must use converters.

  • Tarik Qassem asked a question in R:
    Dataset management in R?

    Are you able to suggest any R package that is good in managing huge datasets?

  • Brahim Bouali added an answer in Language:
    The effect of language skills (learning of language) on learning math ??

    Language learning and acquire skills helps in understanding and applying math skills. Math also a kind of language and mixed with general language as medium of learning

    Brahim Bouali · University of North Carolina at Charlotte

    Dear Joe,

    You are right. I was wrong. I think my interest in quantum mechanics blinded my eyesight-the observer's paradox again. By the way when you apply partial derivatives in Einstein's field equations or Schrodinger hydrogen atom it becomes really complex and funny..

    Anyway, I hereby retreat my offensive words and ask pardon from all the pure math community-it is always good to know..


  • Tarik Qassem added an answer in Long-Term Memory:
    Is there research on long term memory deficits in individuals on Paxil?

    looking for new research

    Tarik Qassem · Ain Shams University

    Dear  Bianca, 

    I think the question is biased (assuming a negative unidirectional relationship between paroxetine "Paxil" and memory). 

    The reason I am saying that is depression is associated with cognitive impairment. Depression is also a risk factor for developing alzheimer's disease. 

    However, you will fine a file that has the result of a quick search on Pubmed. 

    Best wishes, 


  • James F Peters added an answer in Medieval History:
    How did Greek arithmetic give rise to Liber Abaci arithmetic?
    See above.
    James F Peters · University of Manitoba

    In addition to the observations by @Ioannis M. Vandoulakis on Liber Abaci and Greek arithmetic, it should be observed that the Fibonacci sequence is closely related to the golden ratio, which dates  back to Euclid's Elements.    The Liber Abaci, Fibonacci sequence and golden ratio are thoroughly examined in

    N. Kowalsky, Mathematics in Nature, 2012:


  • David Jensen added an answer in Chitosan:
    How can I encapsulate FITC-BSA or FITC-dextran in a polymer matrix (as for example chitosan)?

    I want to encapsulate FITC-BSA or FITC-dextran to study its fluorescent properties and the distribution of protein in a polymer matrix. 

    David Jensen · US Synthetic

    This publication may be of help:


  • Emergency MAD (Maximal Anal Dilatation) for acute fissure in ano. Is it still the practice ?

    Most cases of acute anal fissure don't respond to conservative measures

  • Dmitry Burakov added an answer in Banking Sector:
    What is the minimum acceptable ratio of the volume of banks’ credit to the GDP?

    The volume of banks' credit to the Gross Domestic Product (GDP) is used as an indicator to the participation of banking sector in the economy of a country. What is the minimum acceptable ratio of the volume of banks' credit to the GDP?

    Dmitry Burakov · Finance University under the Government of the Russian Federation

    Well, honestly that's a diffucult one to answer. Some state that the maximum should be 100%. Anything more is above the market demand to produce and realize goods and services which are accounted in GDP. The minimum then must be linked with marginal efficiency of loans granted. If not enough, then the unsatisfied high quality demand for credit would be too high. The problem of measures could be solved by determining the share of informal credit market or the share of commercial credit as a percent of GDP (substitutes for bank credit). Also the correlation of interest rate with credit supply may help. If interest rate is high then supply of credit is rationed.

    Well, simplifying one can say that the minimium acceptable ratio (in numbers) is specific to each country.

    Hope that the answer would be useful.

    Best wishes,

    Burakov Dmitry.