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  • Does anybody know about any protein that is solubilized at low temperatures (e.g. -20 ºC)?

    I want to know if a insoluble protein could be solubilized at low temperatures. Does anybody know any case reported in literature?

    Many thanks.

    Stoyan Stoychev · Council for Scientific and Industrial Research, South Africa

    In what buffer do you resuspend the protein to do the polyacrylamide analysis? And presumably the protein will have to be thawed prior analysis? 

  • What is the difference between anodic and cathodic Micro Arc Oxidation?

    what is the difference between anodic and cathodic Micro Arc Oxidation?

  • Is there any relation between groundwater pollution by sewage and increased uranium concentration in groundwater?Are there references on this subject?

    I could not find any reason or references about this subject

  • Deepesh Velachery 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?

    Deepesh Velachery · Central Pollution Control Board

    Higher agar concentration (3% or more) may do the trick.....it worked fine for me.

  • Debashree Tagore asked a question in Adsorbents:
    If a biosorption process follows Temkin isotherm does it also have to follow Langmuir or Freundlich? Or temkin is completely independent?

    My adsorbent is a dried biological material that adsorbs a solution

  • Abbas Fazel ANVARI-Yazdi added an answer in Nano:
    Does anyone deal with sintering of 3Y-YSZ nano sized particles?

    I had sintered many samples prepared using 3Y-YSZ nano size powder by PAS machine. SEM results for all samples showed an unusual microstructure. Also EDS detected that Cl is one of the compositions of the starting material. Details are available in attached document. Does anyone guess what is/are the problem/s?

    Abbas Fazel ANVARI-Yazdi · Materials and Energy Research Center

    it is an unusual phenomena. but keep try to do that under vacuum circumstances. which company you purchased this Nano powder? you synthesized that? or commercially bought? 

  • What is Alexithymia?

    Alexithymia is a personality construct characterized by the sub-clinical inability to identify and describe emotions in the self. The core characteristics of alexithymia are marked dysfunction in emotional awareness, social attachment, and interpersonal relating. Furthermore, individuals suffering from alexithymia also have difficulty in distinguishing and appreciating the emotions of others, which is thought to lead to unempathic and ineffective emotional responding. Alexithymia is prevalent in approximately 10% of the general population and is known to be comorbid with a number of psychiatric conditions. (Source: Wikipedia)

    A recent article on Alexithymia is given in the enclosed link.

    Your views on Alexithymia are welcome - Dr. Sundar

    Béatrice Marianne Ewalds-Kvist · Stockholm University

    Dear Sundarapandian Vaidyanathan,

    My favorite definition:  

    Difficulty in recognizing and describing one's emotions, defining them instead in terms of somatic sensations or behavioral reactions.
    [G. a- priv. + lexis, word, + -thymia, feelings, passion] Elaboration:

    Quote from below attached reference: Clinical observations have led to the proposal that  alexithymia actually subsumes at least two subtypes (Larsen, Brand, Bermond, & Hijman, 2003; Moorman, Bermond, Albach, & van Dorp, 1997). So-called Type 1 alexithymia refers to the prototypic or classic alexithymic person who has little experience or display of emotion, minimal emotional awareness and verbalization, and a pronounced external orientation. Such people are emotionally neutral or bland, place little value on psychological processes, and relate to others in a rigid, machine-like fashion. In contrast, the so-called Type 2 alexithymic person experiences and expresses heightened levels of negative emotion but has difficulty identifying and labeling his or her own feelings and is confused, overwhelmed, feels numb, or acts out when aroused. If these subtypes are valid, then one might view Mr. A. as manifesting Type 1 alexithymia, whereas Ms. B. shows Type 2.

    J Pers Assess. Dec 2007; 89(3): 230–246.
    The Assessment of Alexithymia in Medical Settings: Implications for Understanding and Treating Health Problems
    Mark A. Lumley, Lynn C. Neely, and Amanda J. Burger

    Abstract. The construct of alexithymia encompasses the characteristics of difficulty identifying feelings, difficulty describing feelings, externally oriented thinking, and a limited imaginal capacity. These characteristics are thought to reflect deficits in the cognitive processing and regulation of emotions and to contribute to the onset or maintenance of several medical and psychiatric disorders. This article reviews recent methods for assessing alexithymia and examines how assessing alexithymia can inform clinical practice. Alexithymia is associated with heightened physiological arousal, the tendency to notice and report physical symptoms, and unhealthy compulsive behaviors. Alexithymic patients may respond poorly to psychological treatments, although perhaps not to cognitive-behavioral techniques, and it is unclear whether alexithymia can be improved through treatment. Interpretive problems regarding alexithymia include its overlap with other traits, whether it is secondary to illness or trauma, the possibility of subtypes, and low correlations among multiple measures.

  • Nand kishor Roy asked a question in Gold Nanoparticles:
    Are Gold nanoparticles toxic to cancer cells ? Also, in which solvent it can be dissolved for cytotoxicity study???

    I have biosynthesized GNPs and wanted to check their cytotoxicity to cancer cells. But after dissolving GNPs in PBS buffer, particles settle down after some time. Please suggest.

  • What I am doing when the author of paper said wash with water and ethanol in chemical synthesis?

    for remove  undesirable ions.

    I dont know the percent of ethanol and water or if they mixed together or not?

  • Jose Meseguer added an answer in Chondrogenesis:
    Is there any advantage of using a serum-free culture medium for chondrogenesis?

    When I search through the litterature for 3-way differentiation of MSCs, there seem to be a tendency for growing MSCs for chondrogenesis in a serum-free media, and instead add supplements like ITS+ premix.

    But I cannot find any arguments for it, so do You know the reason for it?   

    Jose Meseguer · Centro de Investigación Príncipe Felipe


    You should not do the adipo and osteogenic differentiations with medium+fbs. There are specific kits to do the differentitations without serum and adding the specific factors for the induction. 

  • What are the applications of data mining in the municipality?

    What are the applications of data mining in the municipality?

    Actually, what are the applications of artificial intelligence in the municipality?

    Based on polling and data which are gathered from other resources.

    Lütfiye Kuşak · Istanbul Aydin University

    Hi Vahid,

    Maybe this article can be useful for you..

    Data Mining Solutions for Local Municipalities
    Gözde Bakırlı, Derya Birant, Erol Mutlu, Alp Kut, Levent Denktaş and Dilşah

  • 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!

    Vivian M. Nguyen · Carleton University

    Thank you everyone! This is very helpful!!

  • Oluwole Alfred Olatunji added an answer in Cost:
    What is the most common approach Cost to calculate project contingency allowances besides traditional best guess methods?

    please. if possible, give some justifications on why it is common and what factors influence their suitability 

    Oluwole Alfred Olatunji · Curtin University Australia

    Probability distribution method? Read the work of Peter ED Love and David Baccarini

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

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

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

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

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub · University of Massachusetts Amherst

    Erkki, would you be willing to say that any systematic pattern-to-sign mapping is a code?

  • What type of solvent is suitable for bio-glass to study cytotoxicity?

    solvent to dissolve the bioglass powders 

    Abbas Fazel ANVARI-Yazdi · Materials and Energy Research Center

    your question is not clear.

    MTT assay as an in vitro examination is the most practical procedure to study toxicity of bioglasses.

    what do you want to know exactly?

  • K. M. Singh added an answer in RG score:
    RG score and impact points should be considered by Universities for selecting faculties?
    It is always a tough task for universities to select the best faculty. RG score and impact points of scholar may reflect underlying talent and potential of the candidate. So, RG score and total impact points may be used as criteria to select the best faculty by universities.
    K. M. Singh · Indian Council of Agricultural Research

    RG score can not be a true indicator of a scholars worth simply because it is not transparent enough and keeps on changing over time. Till it is known the way it is calculated and what type of contribution gets how much weight is made clear, Further, we already have a system in place to judge the contribution of a scientist/ teacher, it has to be superior to be adopted as a measure to judge them.

  • FC Prinsloo added an answer in Solar Modulation:
    Can anyone help with the design of Floating platform for Solar power plant in lakes?

    I am currently working on designing a Floating structure for Installation of Solar modules in lakes. What are the factors to be considered ? Any technology or designs available for the same? Which is more reliable in long run (20 years) HDPE/FRP or Bamboo structures? Which one is cost effective? Whether the platform can be made flexible to adjust to the local water depth variation during different climatic conditions? 

    FC Prinsloo · University of South Africa

    Dear Sudhakar

    floating bamboo is an excellent idea, it will be cheap and will be a natural low cost building material to construct the solar structure.  You would however have to do tests to see how the structure would be deformed as a result of heating and cooling or drying over time.

    this review on floating photovoltaic structures references a number of installations and is worthwhile to quickly browse through these


    You should also read this article on the Kerala reservoir awaits floating solar farm


    where they plan to install floating solar on water reservoirs using the Kyocera floatation devices to fix the solar panels.



  • Does special education for children with intellectual disabilities in India meet international standards?

    Thanks in advance for your replies.

    Dr. Akhilesh Kumar · Vardhaman Mahaveer Open University

    Dear E. Blaurock-Busch sir although disability is more prevalent among poor people but usually disability may occur in an individual regardless of his/her prosperity or poverty. Poor as well as rich all need to be made aware of all these. It is the responsibility of the signatory state to make their people aware about Human Rights and Disability Rights. Thanks a lot to all of you for taking active participation in  discussion and probing such fundamental questions.

  • N. J. Manju added an answer in Anammox:
    Why is the concentration of ammonia in my reactor is decreasing while nitrite is increasing?

    I am trying to establish anammox bacteria to coexist with ammonia oxidizers. Can someone explain to me why the concentration of ammonia in my reactor is decreasing while nitrite is increasing consistently, and suggest what l could do establish the system.

    N. J. Manju · Garden City College

    Aerobic ammonia oxidizers may be dominating the system, try to limit oxygen supply.

  • P. K. Gautam added an answer in Climate Change:
    Is there any relationship between climate change and Environmental Components?

    What is climate change?

    P. K. Gautam · University of Hyderabad

    yes ! Indeed !!

    In order to understand these environmental parameters' impact on climate change you should go through paleoclimate literature which suggest that there have been climatic changes in the past due to temperature, rainfall, sunlight etc. These are also considered as boundary conditions to understand their impact on climate change in past. It is also appreciable that similar phenomena  are responsible for recent climate changes also.

  • Is Extra Sensory Perception (ESP) for real?

    Often times, we hear about para-normal activities such as Extra Sensory Perception (ESP), etc. What does Science about ESP? Can ESP be real?

    Your comments are welcome.. Muchas Gracias.. - Dr. Sundar

  • Quddusi Bashir Kazmi added an answer in Amphipods:
    Who can help me with material form the amphipod species listed below?

    Amphilochoides boecki Sars, 1892 
    Amphilochoides serratipes (Norman, 1869)
    Cressa dubia (Bate, 1857)
    Deflexilodes subnudus (Norman, 1889)
    Dulichia tuberculata (Boeck, 1870)
    Eusirus longipes Boeck, 1861
    Hyperoche medusarum (Kroyer, 1838)
    Iphimedia minuta G.O. Sars, 1882
    Jassa pusilla (Sars, 1894) 
    Lafystius sturionis Krøyer, 1842
    Lembos websteri (Bate, 1857) 
    Leucothoe spinicarpa (Abildgaard, 1789)
    Melphidippella macra (Norman, 1869)
    Menigratopsis svennilssoni Dahl, 1945
    Metopa borealis Sars, 1882
    Metopa solsbergi Schneider, 1884
    Microdeutopus versiculatus (Bate, 1856)
    Monoculodes norvegicus (Boeck, 1861)
    Orchomenella minuta (Kroyer, 1846)
    Pleusymtes glaber (Boeck, 1861)
    Socarnes vahlii (Kroyer, 1838)
    Synchelidium tenuimanum (Norman, 1895)

    Quddusi Bashir Kazmi · University of Karachi

    presently I can tell  only about Leucothoe spinicarpa which occurs in Pakistan

  • Is there a previuos studies say that there is a relationship between internal marketing and total quality?

    I'm MBA student and I'm preparing to my research about relationship between internal marketing and total Quality in any sector, and I'm looking for a litreture and previous studies

    Rahul Pratap Singh Kaurav · Prestige Institute Of Management

    Dear Sharif,

    You can see my paper, How Internal Marketing Produces Quality in Tourism and Tourism Related Businesses? abstract is available on research gate. If you found it suitable for your purpose then let me know and I will send you full paper. 

  • John George Hardy added an answer in Film:
    How to maintain 50% RH in a desicator?

    I have kept a polymer film inside,temperature being 23 degree celsius

  • Hossein Javadi added an answer in Quantum Physics:
    What are the physical properties of vacuum?

    According to quantum mechanics, the vacuum state is not truly empty but instead contains fleeting electromagnetic waves and particles that detonate into and out of existence. Also, in conventional quantum physics, the origin of zero-point energy is the Heisenberg uncertainty principle. How we can describe quantum vacuum without using the uncertainty principle?

    Hossein Javadi · Islamic Azad University

    Dear Azzam
    "What is the vacuum? Is it empty?" No, vacuum is full of color charge and magnetic color that virtual photons are made up of them.
    Also, time dilation depends to the nature existence. Lorentz transformation is not able to explain beyond the speed of light.

  • Ben Morton added an answer in Anesthesia:
    A formula to calculate Pa02 from Sp02%, anyone have any recommendations?

    I have Sp02% and Fi02%, and I want to calculate a Pa02/Fi02 quotient. Is it possible to calculate a Pa02 from Sp02%? If yes, does anyone have any reliable formulas?

    Ben Morton · Liverpool School of Tropical Medicine

    Pandharipande paper not bad for this


  • Mahdi Izadi added an answer in FLUENT:
    How does Fluent calculate the variables that are not mentioned in boundary conditions?

    In Fluent, when pressure outlet boundary condition is mentioned, we are usually mentioning only the value of the pressure at that boundary, but it is also necessary that even velocity should be mentioned at that boundary due to the very basic elliptic nature of NS equations. Or in other words boundary of the domain should be completely closed for the variables to be found. So how does fluent calculate the other variables at that location internally? (For steady state case)

    Mahdi Izadi · Iran University of Science and Technology

    Dear abhey
    To be honest I couldn't digest your question but I think your answer is in SIMPLE,SIMPLEC,piso and etc. algorithms in which we couple continuity to find pressure in a staggered mesh and solve another equation.I hope this link initiate to solving your question.



  • Brian Thomas Foley added an answer in Toxins:
    How can I find the toxin motif in a toxin gene?

    Hi, I have a sequence of toxin genes of a bacteria. I would like to find out the motif that is toxic and if there is any bioinformatics approaches to it?

    Brian Thomas Foley · Los Alamos National Laboratory

    http://www.ncbi.nlm.nih.gov/pubmed/23805259   describes a crystal structure of a different Clostridial leukocydin.     I BLASTed the CctA protein against the protein databases and it is indeed most similar to a protein annotated as alpha hemolysin from Clostridium botulinum.  But this annotation seems to be from complete genome, by similarity to other alpha hemolysins from other bacteria.  So, there is probably no structure/function information on the Clostridial proteins, but there is enough similarity to the other alpha hemolysins that I would trust that this is truly an alpha hemolysin, and if you dig through the dozens of other alpha hemolysins, there is probably one that has been studied for structure/function.


    is the link to the protein families database on the alpha hemolysins.  From there you can see a sequence alignment and 3D structure.  The next step would be to align your proteins to those already in this alignment, so you can see where your amino acids map onto the structure.