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  • Mirza Arshad Ali Beg added an answer in Carbonates:
    Is it advisable to add FeSo4 in the preparation of HCl solution in carbonate analysis ?

    the acid attack in carbonate analysis produce Co2 gaz which may comme from the oxidation of organic matter, so  i was wondering if the FeSo4 can eliminate this oxidation and by which mechanism it can do so?

    Mirza Arshad Ali Beg · Research & Development Consultants, Karachi, Pakistan

    Yes, HCl reaction/titration will give you inorganic carbonate and bicabonate and will not oxidize the organic matter. You may have estimate the carbonate and bicarbonate and organic matter by standard procedures, one wof which may involve estimation of soluble carbonate and bicarbonate. The other may require dehydration followed by desiccation and finally incineration from which you will find out the moisture content, the organic matter and the carbonate content.

    Mirza Arshad Ali Beg  

  • Haidar Raimy asked a question in Acceleration:
    What the error means ? and how to overcome this error?

    I'm trying to run a (dynamic,explicit ) analysis by using acceleration input in BC . However, there are two major errors popped up :

    i. The ratio of deformation speed to wave speed exceeds 1.0000 in at least one element. This usually indicates an error with the model definition. Additional diagnostic information may be found in the message file.

    ii. There are a total of 22 excessively distorted elements

    For information, i have turned on the "distortion control". Does anyone know what is the possible cause ? how to overcome these issues?

    Helps needed, best regards.

  • Ajit Behera asked a question in Magnetron Sputtering:
    How to make free-standing film from a constraint thin film?

    Suppose we are depositing NiTi on Si substrate by magnetron sputtering. Give me different type of process, How I can make a freestanding film from that constraint film. When I am going to etch the substrate, I am getting irregular geometry, which is not good to get a perfect result. So suggest me some idea about this.

  • What's the best heterologous expression system for recombinant expression of fungal Feruloyl esterases?

    Most well-characterized feruloyl esterases are fungal enzymes which usually require eukaryotic expression systems, such as Pichia pastoris system. On the other hand, bacterial feruloyl esterases can be made accessible through recombinant expression using well established Escherichia coli systems. E. coli expression system is suitable for protein engineering and high-throughput structural analysis

    Christoph Kulmann · Universität Bremen

    It may be worth trying expression in E. coli. With some luck, you may get your results much faster than in P. pastoris. Optimizing expression in P. pastoris can be very time-consuming.

    I suggest you do a very thorough research of the relevant literature. You must know the size of your protein (there are upper limits for expression in E.coli), you must check for post-translational modifications and any influence in different codon usage between the organisms. If your protein is rather small and does not have many modification sites and if the codon usage of E. coli does not destroy any critical sites, then an expression in E. coli may be worth a try (secretion into the medium, if possbible).

    But you are well advised to set yourself a limit. If expression in E. coli is not successful after X months, you should switch to another system. Pichia pastoris is one option, Saccharomyces cerevisiae another one. There are also expression systems available for Schizosaccharomyces pombe and Trichoderma sp. 

    It depends to a great degree on your time-frame and available ressources. Do you want to establish an expression system in your own lab, do optimizations on your own or do you need it to be done rather quickly, in a narrow time-frame?

    If you ask the right people, maybe you can have your expression done in hands already experienced in a specific expression system. Offering "cooperation", for example co-authorship for the resulting paper or some kind of payment is always a good idea. ;)

    Good luck.

  • Ofer Erez asked a question in Derby:
    Are you the one that can help us?

    My name is Ofer Erez.

    I am a 53-year-old psychotherapist practising in Israel, specialising in the treatment of adolescents and parental guidance.

    For the past 8 years, I am also an Ed.D (Doctor of Education) student at Derby University, UK, conducting my research in Israel.

    I am appealing to you for help, as I believe my supervisors are seriously impeding the completion of my research.

    The attached letter is a description of my experience as a student there.

    I would be grateful to receive any kind of advice or help with this issue, as all my efforts through the formal channels at the university have failed.

    Yours Sincerely

    Ofer Erez (Doctoral student)

    M.Sc. @ C.B.T @ Derby University

    Kelim Shluvim-diagnosis, treatment and supervision, LTD. 

  • Xiyao Long added an answer in RNA Splicing:
    Are the inclusion of exons during RNA splicing independent from each other, even they are adjacent?

    I'm wondering that if we have exon 1, 2, 3, 4, 5. Is the inclusion/exclusion of exon 2 and exon 3 independent of each other during alternative splicing? 

    Xiyao Long · University of Illinois at Chicago

    Thank you very much for your answer. The inclusion of an exon then may affected by the acceptor site of its preceding intron, but not tool much about the receptor site of its preceding intron (in another word the inclusion of its previous exon). Is this how the reasoning goes?  

  • Zeeshan Haider added an answer in Photodegradation:
    How can I Calculate Apparent Quantum Efficiency For Broad Band or Panacrhomatic Radiation ?

    I am studying photodegradation of Rhodamine B (RhB) dye under visible light irradiation. I want to calculate Apparent Quantum Efficiency of RhB degradation model. I have found an expression as follow  

    Apparent Quantum Efficiency (AQE) = (dx/dt)/(d[hv]inc/dt).  [ref: Chem. Rev.1995,95,69-96).

    dx/dt can be considered as rate of change in RhB concentration.

    (d[hv]inc/dt) can be referred as photon flux or total optical power incident on the sample.

    I need to find out d[hv]inc, for specific radiation intensity for example 10 mw/cm2.

    I came to know that it is easier to find out the value of photon flux d[hv]/dt for monochromatic source of light (single wave length radiation). However when incident radiation is broad band or rang of wavelengths, in this case how can i convert radiation intensity into photon flux. ?

    Thanks for having look on query !

    Zeeshan Haider · Sogang University

    Professor Adela E. Croce, Thanks for suggestion.

  • Md Anwar Hossain added an answer in Strabismus:
    What is the management for teenager sufferring recent onset transient concomitant exotropia ?

    What is the management for teenager sufferring recent onset transient concomitant exotropia ?

    14  y.o. girl's parents revealed  2 yeras ago strabismus in her dauther- transient alternating exodeviation dominantly in her left eye, more prominent when girl is tired.

    VA 1.0

    Concomitant strabismius 10-15 degree . Anterior and posterior without abnormality. The girl has headaches without localization Neurologist reject any pathology.

    What is your opinion ?

    Md Anwar Hossain · Combined Mil Hospital,Dhaka, Bangladesh

    Thanks Eric. Nice explanation. What should be your principle of treating high exophoria. What about treating patient w orthotptic/adverse prism treatment How to  combat central suppression What may be the status of BSV?How do you develop firm stereopsis in this patient?

  • Can anyone recommend me a measurement scale that can measure teachers' beliefs about assessment / evaluation in school?

    I need to identify the conceptions of assessment that teachers of primary and secondary have about classroom assessment practices.

    Zorena Leatherbury · Capella University

    I have found this link that may give you insight on how teachers conceptions and perspective of assessment may be clouded because of lack of training or other barriers that may or may not influence assessment practices. 

  • Eddie Seva See added an answer in Import:
    Are you happy with your job?
    • Do you live in a good environment at your job?
    • What does make your job different than the other ones?

    I'm happy at my job, because I can talk to my students, and teach, but the most important part at my work is that I learn a lot with my students or with my son.

    Your opinion is always important, furthermore, you are important.

    Eddie Seva See · Bicol University

    Yes because I'm working on what I wanted and want to work on. The returns just follow proportionately to my happiness.

  • Azlan Muharam added an answer in GPU:
    Can anyone comment on the performance of using FPGA and GPU for image processing ?

    In term of time, latency, throughput,area and slicing

    Azlan Muharam · Universiti Tun Hussein Onn Malaysia

    many thanks for those ideas and comments really appreciated.

  • Can someone point me towards some recent research on muscle activation and muscle re-education techniques?


    I am looking for research on various muscle activation and muscle re-education techniques within the fields of physical therapy or sport science and kinesiology. 

    I am writing an article on prehabilitation techniques for trainers and athletes.

    Any and all recommendations will be greatly appreciated! Thank you-


    Mohanakrishnan Jagadevan · Jawaharlal Institute of Postgraduate Medical Education & Research

    If its sports rehab then PNF techniques could be handy and effective in reeducation

  • Can anyone give me the correct time for measuring of absorbance after adding buffers (pH1 & pH4.5) in determination of total Anthocyanin?

    I am conducting an experiment to quantification of total anthocyanin in Tea (Camellia sinensis) using spectrophotometric method. I took absorbance at 520nm and 700nm with two buffers (pH=1 and pH=4.5) as formula mentioned in Journal of AOAC International vol. 88:5 1269-1278 (Lee et al, 2005) in determination of total Anthocyanin.

    According to formula Absorbance (A)= (A520nm – A700nm)at pH 1.0 - (A520nm – A700nm)at pH 4.5

    Literature suggested to take absorbance within 20-50 min of preparation. But absorbance is increasing continuously with the time (even less than 20min) at both 520 nm & 700nm only in pH=4.5 buffer. As a result of higher absorbance values, final value become negative (difference between Abs at pH=1 and pH=4.5). Please anybody explain this incident or suggest any other spectrophotometric method for quantification of Anthocyanin in Tea.

    Jeevan Dananjaya Kottawa-Arachchi · Tea Research Institute Sri Lanka

    Thank you Sir.

  • Is there any drug, which can induce cancer cell differentiation?

    I would like to know about cancer cell differentiation. After inducing differentiation it may reduce tumorigenicity. If somebody can provide reference article and reference drug, that would be very helpful for my research. Thanks in Advance.

  • Thi Xuan Chu added an answer in SU-8:
    Problem when spin coating dilution of SU-8 3050:Cyclopentanone = 1:4.2 in volume?

    I would like to obtain SU-8 layer of about 400 nm thickness in Si wafer. For this purpose, I mixed SU-8 3050:Cyclopentanone=1:4.2 in volume with magnetic agitator for 15 min. This dilution was spin coated on Si wafer at 500 rpm for 5s; slope 5 s; 3000 rpm for 30s. The Si substrate was cleaned with acetone, IPA, de-ionized water and put on the hotplate at 150oC for 10 min before spin coating. The obtained SU-8 base layer was not uniform. When observing in the microscope, it seems that there are many small droplets on the surface of Si wafer. Anyone can help me to overcome this problem to obtain a uniform SU-8 base layer with 400 nm thickness on the Si wafer?

    Thi Xuan Chu · International Training Institute for Materials Science

    Dear Dr. Tillmann Krauss,

    I tried to add more SU-8 3050 (SU-8 3050:CP=1:2), there were less droplets on the surface. So I wander if the problem comes from the SU-8 ratio? Do you think that the SU-8 3050 was too diluted with ratio 1:4.2? I also tried to let the mixed solution several hours before spinning for degasing but nothing has changed. However, I will try the vacuum application and inform you.

    The substrate was heated at 90oC after the spinning. Yes, the droplets appreared just after the spinning,

    Thank you very much for your time and help.

    Best regards,

    Chu Thi Xuan

  • Maria Garcia added an answer in Primer:
    Do I need two sets of primers for each gene for the Fluidigm gene expression array?

    I have conflicting recommendations from Fluidigm tech support and users as to whether it is worth it to run each gene with two sets of primers. I am running a 96.96 gene expression array on multiple mouse tissues. With wet lab testing available, it seems like overkill to use two sets for each gene. But because each chip is so expensive, it might be worth it to investigate my top genes of interest more thoroughly. Any recommendations?

    Maria Garcia · North Georgia College and State University

    Considering that the chips are quite expensive, I do think that it would be beneficial to run each gene with 2 sets of primers. Good luck!

  • Milankumar Prajapati asked a question in PVDF Membrane:
    Does it really matter, which side of PVDF membrane after transfer for probing and exposing it for imaging ??

    Western blot.

    Transfer using PVDF or Nitrocellulose.

    Is it recommended to probe ab on facing side (the side that is facing gel) and take image on facing side ??

    Or it doesn't matter at all which ever side is ?

  • Why do HIV patients carry higher risk of allograft rejections in Kidney transplantation?

    Why do HIV patients carry higher risk of allograft rejections in Kidney transplantation?

    Any suggested biological evidence, or reasoning explained by immunology or animal models?

    Thank you

    Deborah Jean Verran · Royal Prince Alfred Hospital

    There are two hypotheses as outlined in the discussion section of the recent publication in the NEJM of the South African experience of transplanting deceased donor kidneys from HIV +ve donors into HIV +ve recipients.


  • Can anyone suggest me some literature about the load balancing and different load balancing algorithms in cloud computing?

    I need some good material about load balancing so that i could get some general idea about what it is and what are the different load balancing algorithms. 

    Yaik Boon Ooi · Universiti Tunku Abdul Rahman

    Which type of load balancing are you referring? Load balance the VMs between the physical hosts? Load balance the no. of. services in between VMs ? or Load balance incoming service requests between different services? =)

  • Could you please suggest some papers to support my thesis, see thesis below?

    Thesis: A person’s level of emotional intelligence will have an impact on how they respond to bullying in the workplace. I'm looking for any papers that relate to my thesis statement especially in the areas of types of work place behaviours i.e. interpersonal and intrapersonal behaviours, emotional intelligence, the negative effects of workplace bullying i.e. physiological and physical harm, the negative impacts on the work environment and those that witness workplace bullying, and how to respond to workplace bullying i.e. management, prevention and the approaches used to address workplace bullying.

    Also, I would greatly appreciate any other areas you think my essay should focus on this essay is due in a weeks time so am very busy researching.

    Thanks for taking the time to read this


    Shenae Tompsett · University of Southern Queensland

    Thank-you everyone for your responses,

    You have produced some very credible sources that I am looking into know as we speak.

    I sent a copy of my essay plan to my lecturer and she has advised me that the topic sentences are about bullying, not about emotional intelligence.

    So, I am going to tease out the elements of EI to show how they can help with bullying.

    Each topic sentence will be a reason why peoples level of emotional intelligence influences how they respond to bullying in the workplace.

    Could you please send me any other credible sources you think will help support my argument  and would greatly appreciate any other feedback you may have for my essay.

    Thanks again,


  • Tausif Alam 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.

    Tausif Alam · University of Wisconsin–Madison


    "I don't know how to consider such a comment but it doesn't look very friendly."

    I really wish you wouldn't overanalyze inconsequential things.

  • Kenneth M Towe 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 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 is 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 quickfix 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 quickfixes 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.

  • Sonja Hess added an answer in Iodoacetamide:
    Can a threonine residue suffer alkylation?

    A threonine residue can be alkylated during a alkylation process using iodoacetamide if occurs overalkylation in the protein?

    Sonja Hess · California Institute of Technology

    Any nucleophile can be alkylated, thus threonines can be alkylated.

  • Maria Garcia added an answer in Crayfish:
    How do I prepare dried or lyophilized DNA without using any sophisticated device?

    I am working with fresh crayfish gill samples from the field and would like to run PCR to look for mitochondrial DNA gene 16s. I have to lyophilize the DNA without an expensive machine- just want a simple method that works correctly.

    Maria Garcia · North Georgia College and State University

    Thank you all for your suggestions.

  • What are the recent trends in benthic productivity studies in estuarine systems?

    Can i know recent trents in benthic productivity studies in estuarine systems..?

  • Is anyone familiar with forage fibre analysis of NDF and ADF solution?

    Does anybody know of a good recipe for creating a neutral detergent solution for NDF analysis via reflux digestion (as by Van Soest).

    Thank you.

    Ricardo Augusto Mendonça Vieira · Universidade Estadual do Norte Fluminense

    Dear one, the standardized procedure is:

    Mertens, D. R.  Journal of AOAC International, Volume 85, Number 6, November 2002, pp. 1217-1240(24).

    Remember, fiber (aNDFom) is an empirical measure determined exclusively by OPERATIONAL CONDITIONS. Therefore, results, if one wants to produce comparable results, at least, must follows the standardized procedures exactly.

    If you do not want to use the reference method above, the Reference Van Soest et al is an important one, because he provides the 8M Urea solution for pre-soaking amilaceous feeds and emphasize the facultative use of sodium sulfite. Nevertheless, the use of Amylase is mandatory too. The problem with amylase, however, relies on the fact that it also contains fibrolytic activity. That´s why Mertens (2002) provide the way for stadardizing the amylase solution to clear enough starch without damaging fiber.

    Please check the recommendations for nomenclature on fiber provided by the editorial board of Anim. Feed Sci. Technol.

  • Kenneth M Towe added an answer in Cremation:
    Is anyone doing research on contaminants from crematorium/cremation process?

    I am looking to compare/discuss patterns of metals distribution in soils, vegetation, birds and small mammals in areas near the vicinities of crematorium, including associated human health risks in North America (Canada), Asia and Europe. I am open to collaborating with researchers from any country interested in following this line of inquiry.

  • Andrea Menegotto asked a question in Todo:
    ¿Cómo fue el entrenamiento?

    Hola Joaquim. Tengo un par de dudas en relación a cómo fue el entrenamiento en el experimento. ¿Cuántas veces estuvieron expuestos a la misma asociación de sonido/imagen, solo seis en total, o se repitió en cada bloque, o sea 24 de entrenamiento y 6 de prueba? Todo el entrenamiento fue en una sola sesión de 25 min, o los bloques estuvieron separados en el tiempo? Gracias por la aclaración!

  • Nitin Varma added an answer in Text Mining:
    Will anyone please suggest about sites that generates freely downloadable data in text/csv/xls format (other than Google Trends)?

    I need the sites that generates and shows human interest data over time based on the keywords. I don't need the business sites like Alexa or Compete where I have to put the website as query. I prefer the websites like Google Trends where I can generate the time-graph using some keywords. Will you please suggest some names?

    Nitin Varma · Indian Institute of Management

    Partha, I hope the following sample data-sets will be of use for your current needs:


    They have some demos which seem to be in line with what you are looking to do.

  • What is the purpose of using frequency window 1 kHz to 1 MHz, while measuring/analyzing the dielectric constant of any material?

    I frequently seen that people check the frequency dependence of dielectric constant of materials in frequency range of 1 kHz to 1 MHz. What is the purpose of this frequency range or simply in which applications this frequency range is important. please tell different frequency ranges for different applications.

    Pramod Kumar Sain · Malaviya National Institute of Technology Jaipur

    Dear Dr. Nobre and Dr. A. Kumar:

    Thank you for your helpful answers

    Please guide for one more thing.. In a perfectly dielectric material when we increase the frequency the dielectric constant decreases due to the mismatching in the relaxation time and field frequency and concurrently what should be happen to  dissipation factor? (it should be decrease as I think)... 

    In polymer composites filled with conductive particles, the dissipation factor increases with increasing frequency below a critical filler concentration (below this the composite shows dielectric nature), but beyond this critical concentration (here the composite becomes conductive) the dissipation factor decreases almost linearly, Why?