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  • Sergei Esipov added an answer in Monetary Theory:
    Are there any papers or books which examined historical change of the concept "hoarding"?

    I am wondering why the concept of hoarding has disappeared after Keynes's General Theory. Are there any economists who tried to extricate the concept of Hoarding after Keynes?

    The concept of Hoarding was once one of the most important ones. For example, it was an essential part of D. S. Robertson's framework of his monetary theory. However this concept does not play any conspicuous role in the economics after Keynes. It was practically wiped out from economics. As I have observed in my post of December 13, 2014 to my own question "Is saving necessarily invested or not? How can this contradiction in Keynes be solved?", it seems that Keynes's Liquidity Preference concept has replaced and wiped out the concept of Hoarding.

    I am thinking to save the concept of Hoarding and coin it anew as an essential part of the monetary theory of productions. In that purpose, I want to know the conceptual history of the this notion.

    Sergei Esipov · Quant Isle Ltd

    Dear Yoshinori,

    To consider your question (does 'hoarding' cause an increase in vigor, and in chances of default) one notes that both of these changes are measurable quantities. The economic 'vigor' is a vector of variables (e.g. inflation, labor costs, unemployment rate, payrolls, labor force participation, GDP, housing, and interest rates), and so is the default rate. These observable variables depend upon time and anticipate future quite differently, so that to make a step one should simplify. If I understand correctly, at the level of split real economy/financial economy, no difference remains between the economy and 'a firm'.

    This hypothetical firm has assets, and it is engaged in production, generating a periodic income. The income services layers of debt, and some of it remains. The remaining part, if positive, can be a measure of 'vigor'. If it is negative, it could be a measure of default. The issue of 'hoarding' is then the issue of restructuring the debt by borrowing more money to maintain asset viability. It anticipates that in a world of cheap commodities the return on assets might improve, thus justifying 'hoarding'. This is not exactly Modigliani-Miller, because, volatility of the components has to be considered. It is not a DRI-econometrics either because an effective description reduction is attempted where only a few key flows are taken into account.

    Not sure that I understood you correctly, so please feel free to comment if you have time.

    Best, S.

  • Kamal Eddin Bani-Hani added an answer in Reading:
    Have you come across any readings on participants' drop outs during research that I can refer to?

    I am looking for references that discusses about students' dropping out from research especially of long-term research. Your kind response is appreciated.

    Kamal Eddin Bani-Hani · Hashemite University

    See also this article titled: Special Report / Why Students Drop Out. Amy M. Azzam

    at this link:


  • Is it possible to differentiate between Mycoplasma contamination and cell debris?

    I have been using mouse mammary adenocarcinoma cells and I have recently observed black dots. I was doing Puromycin-kill curve and so the cells were treated with Puromycin. I am not sure if the black dots are cell debris or mycoplasma. I also have untreated one where the black dots are very less in number compared to the treated ones. Been going through lot of related questions.. I would say they are irregular in shape, not moving and are adhered. I have not done DAPI yet to check for mycoplasma.. 

    Anuroop Venkateswaran Venkatasubramani · Institute of Genetics and Molecular Medicine

    Hi Patrick!! I am using DMEM medium.. Does usage of different medium have any influence?

  • What splits us up?

    What renders common communication so difficult at times? What makes solidified human relations scarce and unusual sometimes?

  • Mingqing Wang added an answer in Digital Holography:
    How can I reconstruct a clear image plane digital hologram?

    As far as I know, the angular spectrum method is a good idea, but I cannot get a clear reconstructed image. Could you give me some advice?

    Mingqing Wang · Beijing University of Aeronautics and Astronautics (Beihang University)

    Dear professor Garcia-Monreal

    The object is a clear Chinese character. As far as I am concerned,the object is diffuse because of the exsistance of fringe pattern. At the same time, I agree that there are  very high frequencies in the hologram. But  I have no ideas to remove them. Could you give me some ideas? By the way ,may I have an example of image plane digital hologram of your group? Thank you so much for all the help that you have been giving me.

  • Vladimir Joukov added an answer in Centrosome:
    What protocol can I use for the pre-fixation permeabilization of adherent cells in culture?

    For years we have had occasional need to permeabilize cells prior to fixation and later use in immunofluorescence studies. This lowers cytosolic staining and increases our ability to see some centrosomal or mitochondrial proteins, either endogenous or over-expressed proteins. We have used saponin at 0.02-0.1% for 1-5 min in PBS or culture medium. But lately our results are quite inconsistent and we are also seeing changes to mitochondrial morphology, one of the things we are studying. Does anyone have a protocol they like, that yields consistent results, and ideally with minimal perturbation to organelles?

    Vladimir Joukov · Harvard Medical School

    We had good results with the permeabilization protocol from Mary Dasso’s lab (Joseph et al., J. Cell Biol. 2002, 156:595-602). Cells are permeabilized for 3-4 min at 22ºC in 0.005% digitonin in “transport buffer”: 110 mM potassium acetate, 20 mM HEPES (pH 7.3), 2 mM magnesium acetate, 0.5 mM EGTA, 2mM DTT, + protease inhibitors (filter the solution before use) followed by paraformaldehyde fixation. The digitonin stock solution is at 50 mg/ml (5%) in DMSO, stored at –20ºC. We found this protocol to be particularly useful to lower the IF signal from soluble cytosolic proteins, e.g. in protein overexpression experiments.

  • S. G. Tan added an answer in Peer Review:
    When does a rejection of a scientific paper become beneficial to the author? Have you experienced a rejection that worked out for your good?
    All of us go through this experience. We love our research, we work very hard at it. We want to share it with the scientific community and the lay people. But, sometimes our paper is not accepted. Two of 3 reviewers came back with some comments that may not be called for.
    When does a rejection work out for your good? What were the circumstances? Please share for the mutual benefit/s of our RG community.
    S. G. Tan · Putra University, Malaysia

    Rejection of papers is part and parcel of academic life. Young or matured researchers we have all experienced it. Treat it as a learning experience and you will not feel frustrated.

    Have a Blessed Christmas & New Year 2015 to Miranda et al. Cheers.

  • David Collins added an answer in Biostatistics:
    Can somebody recommend a text book for biostatistics for health sciences that for undergraduates, that is simple, clear and cover important topics?

    Can somebody recommend a text book for biostatistics for health sciences that for undergraduates, that is simple, clear and cover ALL the important topics? Thanks

    David Collins · Virginia Polytechnic Institute and State University

    Although I've used this book in a graduate level class, it is VERY help and easy to follow so I would still recommend for undergraduates:

    Biostatistics: A Foundation for Analysis in the Health Sciences, 10th Edition by Wayne Daniel and Chad Cross. It really is a great book and covers many important topics and great examples. 

  • Ping Kwan asked a question in Hippocampus:
    How to store the animal body for later use?

    In regard to the preparation of acute brain slices, animals are anaesthetised, confirmed areflexia, and then decapitated. In my case, if I am going to study the hippocampus, then only the regions containing the hippocampus will be prepared as acute brain slices while other parts of the brain (e.g. cerebellum) and the rest of the body will be discarded.

    As I think it is so wasteful that those precious discarded parts/tissues/cells can actually be reused in other studies/applications (e.g. make primary cells) especially my animals are not transgenic, I was wondering whether there is a way to preserve this parts. The ultimate storage will be in the -80C freezer.

    Thank you very much in advance.

  • Abhijit N Kadam asked a question in XPS:
    How much powder sample is required for XPS analysis?

    I am  going to characterize

    powder sample by using XPS

  • Are there any Maple experts interested in research collaboration?

    I am looking for people who are fairly knowledgeable with Maple to do some collaborative research in Algebra. No knowledge in Algebra is necessary however. The programming will be very basic and will consist of creating short programs that generate elements and classify them into disjoint sets. 

    Jose Luis Ramirez · Universidad de Carabobo, UC

    I have worked with Maple, I'm not an expert but we can do some works

  • Do you know research in the field of cognitive science on the subject of knowledge creation?

    I am researching if space can foster innovative thinking and would like to know if there is any literature on knowledge creation in the field of cognitive science?

    Jorge Frascara · University of Alberta

    I cannot remember literature on the topic, but I know by experience and have read that visual experiences help develop thinking models and strategies. Vision is an extension of the brain, so, it's no wonder that the link exists. Sensory depravation environments have been conceived as a form of torture that finally destroys your capacity to think straight. Conversely, it follow that rich visual experiences might help feed brain strategies. Think of a man that all his life is facing a bookcase: quite likely he will organize his ideas in shelves, or in a cartesian double entry model. I could go on for a long time on this, but I guess you get the gist. I will appreciate it if you find something of the sort in cognitive psychology and pass the info back to me. Best regards, Jorge

  • How can we integrate theory of planned behavior with Elaboration likelihood Model for advertising research?

    My research topic is "Attitude towards Controversial Advertising : Developing a new model by generational cohort "by adapting Dr Waller -A proposed Response Model for Controversial Advertising.The suggested underpinning theories will be Theory of planned behavior (TPB)and Elaboration Likelihood Model(ELM).I am looking at how to integrate TPB & ELM? Grateful for any comments and advice.Thank you very much.

    John Ch'ng

    Raj Dash · Indian Institute of Management Bangalore

    TPB is an extension of TRA.

    Can you please elaborate on your question?

  • Isaiah Owusu Gyan added an answer in Graphene:
    What is the difference between the CNT and graphene? Ie can I take published instructions for CNT and use them to create graphene?

    I read something interesting on CNT and I wonder if I can use this procedure to make graphene.

    Isaiah Owusu Gyan · University of Idaho

    I could see that previous answers are trying to address your question from a wide array of properties. This is because you did not name the specific instructions you are talking about. From my understanding, you read something interesting on CNT and you are wondering if you can use that procedure to make graphene. This means, you may be talking about graphene synthesis and whether it is possible to adopt a CNT synthesis method you have read about and not that you wish to make one from the other. Obviously, CNT and graphene have same graphitic sp2 backbone. The CVD method of synthesis is common to both materials however, the fact that the method results in tubes for CNT and planar sheet(s) for graphene means that, the conditions are different.

    If you can post exactly what you mean, maybe you can get further help.

  • Samantha Bernardo added an answer in Maternal:
    Can somebody recommend a free instrument measuring maternal sensitivity that would be appropriate for infants with multiple disabilities?

    I am looking at mother-infant interaction in young children (aged 7-15 months), with hearing impairment and other additional/complex needs, using video recording of dyad's interaction. 

    Samantha Bernardo · University of Sydney

    Yes, the 'free' part is what I've found to be difficult. Thank you for this!

  • Victor Rodov added an answer in Cucumber:
    Has anyone scientific results about benefits of shrink-wrapping of cucumbers ?

    I need Information about physiological postharvest behaviour of the fruit with and without wrapping. Attributes like colour, firmness, weight loss, decay are of interest. 

    Thanks a lot

    Victor Rodov · Agricultural Research Organization ARO

    See the reference below. In its literature list you may find some earlier papers on his subject. 

    Rajinder Kumar Dhall, Sanjeev R. Sharma, B. V. C. Mahajan. 2012 Effect of shrink wrap packaging for maintaining quality of cucumber during storage, Journal of Food Science and Technology ,Volume 49, Issue 4, pp 495-499

  • Siddhi Joshi added an answer in Marine Sciences:
    Does anyone have some experience with outreach for a Crowdfunding of a Science Projector and could help with it?
    We started a crowdfunding campaign on indigog recently and we still need some help regarding outreach. we already wrote to a lot of newspapers and radio as well as some blogs, but most of them did not get back to us. Does someone has maybe some tips or do know a journalist who might be good to approach? Check out our Ocean Sampling Day Project on indigogo!
  • By which mechanism dose Phenoxybenzamin increase cardiac output?

    Most heart receptors are innervated by β adrenergic receptors and Phenoxybenzamine is a potent α-adrenergic blocker, so it has no effect?

    Kamal Eddin Bani-Hani · Hashemite University

    The increase of cardiac rate and output produced by phenoxybenzamine is principally mediated by baroreceptor reflexes acting through sympathetic cardiac nerves or circulating catecholamines.

    Please see:


  • Kazuo Ohnishi asked a question in Happiness:
    Best microplate for anti-peptide ELISA?

    Peptide antigens are difficult to be immobilized on the surface of ELISA plates.

    There are several methods for the immobilization, such as NHS-reaction, epoxy-reaction etc.

    I would be very happy if somebody can tell me which method is the best for peptide-immobilization to ELISA-plate, in terms of the efficiency for antibody accessibility.

    Thank you very much in advance.

  • John Tarus added an answer in E-Learning:
    Which new hybrid filtering recommendation technique is suitable for e-learning that can address cold-start problem?

    Which new hybrid filtering recommendation techniques is suitable for e-learning that can address cold-start problem? I need a technique especially that can be hybridized with collaborative filtering or content based while putting into consideration the heterogeneous nature of e-learning content which includes text, images, audio and video as well as the sequence of acquiring knowledge in learning.

    John Tarus · Moi University

    Thanks Salina Jeptoo, that is a good suggestion that may solve the problem in question. Combining content based and collaborative is a bit old technique but the other two can work. Was also thinking something like Sequential Pattern Mining which may take care of the learners nature of acquiring knowledge in sequence.

    Alfredo & Douglas, what I am looking for is a new technique for automatic recommendation of learning resources to learners in an e-learning environment using an hybrid approach. So the question is which technique can be hybridized with collaborative filtering to give better performance and accuracy while solving cold start problem at the same time.

  • Do you think whether it is proper to connect gravity exclusively with the speed of light?

    Since the beginning of the twentieth century the speed of light is thought to be fundamental to gravitation and its transmission effectiveness. Mathematical physics seeks whether this idea is sufficient for explanation of all phenomena related to mass attraction. Is a change of position needed? What is your opinion?

    George E. Van Hoesen · Global Green Building LLC

    Even Albert Einstein had his wind taken from his sails about the cosmological constant only have us revisit it after his death and say well we still need to use the constant or the equations do not work correctly.  So if we still thought that the new way left no room for the old then we would have been wrong.  Is this the type of thing we are arguing about? 

    Also there are different ways to look at everything under the sun.  Say the light postulate could be seen differently but no one will admit it..

  • Can anybody suggest standards in vocational training for people with disabilities?

    Hi! We are working in a Project trying to define standards for training to employment, vocational training for people with disabilities.

    We are looking for different standards based on types of disability, and related to Methodology, Resources and Equipment and Infrastructure reviews or articles were welcomed if anybody knows.

    Thanks in advance!!!

    N. McClennahan · Arcadia University

    When you think about equipment, that sounds like assistive technology would come into play. That would have to be individualized so that the standards would need to be highly generalized, while keeping in mind that a one size fits all approach would be out of the question. I would think that this would pose a challenge in creating standards for a group in which there are so many variables to consider with so much individualization included in the specifications for example. Here is a links to web sites that list sources and suggestions that may be useful to you:



  • Can anyone tell me in what respect legendre polynomial is better than chebeyshev , while using for polynomial approximation?

    Can anyone tell me in what respect legendre polynomial is better than chebeyshev , while using for polynomial approximation?

    R. C. Mittal · Indian Institute of Technology Roorkee

    In polynomial approximation, Legendre polynomials are not better than Chebychev ones in the sense that the interpolation error is minimum only when you select nodes as zeros of Chebychev polynomials. However, error in Legendre polynomial is less. Both them do not exhibit Runge phenomenon which generally happens in case of equispaced points interpolation.The Legendre polynomials are useful in finding solutions of Laplace equation in Spherical coordinates.

  • Kamal Eddin Bani-Hani added an answer in Tea:
    What are the medicinal benefits of lemon tea?

    Some excerpts from the article: "Medicinal benefits of lemon tea" by Mala Srivastava:

    "Tea is a good calorie-free substitute for sugary beverages, according to the Harvard School of Public Health. If you add a squirt of lemon juice to your tea, it will not only enhance its flavor but will also provide multiple health benefits. For example, if you are experiencing nasal congestion, drinking lemon tea can help to decongest your blocked nose, reports the University Health Service of Rochester University.

    Vitamin C Benefits

    One fluid ounce of lemon juice contains 12 milligrams of vitamin C. Water-soluble, vitamin C helps fight free radicals -- rogue molecules that damage your DNA. Free radicals may contribute to the development of diseases such as cancer and heart disease, notes University of Maryland Medical Center. By counteracting the negative effects of free radicals, vitamin C helps decrease the risk of developing cataracts by 80 percent, according to the book "The Secret Benefits of Lemon and Honey: Secret Guides.” In addition to healing wounds, vitamin C helps maintain and repair your teeth and bones. Moreover, your body requires this antioxidant to form collagen, a protein used to build skin, blood vessels, cartilage and tendons.
    Bioflavonoid Quercetin

    Citrus fruits, such as lemon, are one of the primary dietary sources of quercetin. A flavonoid, quercetin protects the insulin-producing cells in the pancreas from the damaging effects of free radicals. In addition, quercetin has an anti-inflammatory effect, as it helps stabilize the cells that release histamine in your body. Histamines are chemicals that trigger allergic reactions. According to the American Cancer Society, quercetin can inhibit the growth of cancer cells and can help promote apoptosis, a type of cell death. Animal studies have shown that quercetin may exhibit a protective effect against certain types of cancer, especially colon cancer.

    Blood Sugar Control

    High blood sugar occurs when your body produces inadequate amounts of insulin or when it cannot utilize insulin properly. Hesperidin, a compound in lemons, can modify the function of enzymes that affect your blood sugar levels, according to a study published in the January 2010 issue of the “Journal of Clinical Biochemistry and Nutrition.” This not only shields your body from the early stages of diabetes but also helps avert diabetes complications if you already have high blood sugar. Additionally, hesperidin has cholesterol-lowering effects.
    Powerful Limonoids

    A study published in the “Journal of Nutrition” in April 2005 revealed that lemons contain compounds called limonoids that have the potential to impede the growth and development of cancer cells. Not only did limonoids decelerate the growth rate of cancer cells, but they also enhanced cancer cell death when tested against human cancer cells. The study further states that these anti-cancer agents have free-radical scavenging activities."

    Your views are welcome! Thank you - Sundar

    Kamal Eddin Bani-Hani · Hashemite University

    Dear Sundar,

    Lemon juice and lemon tea are very healthy drinks and excellent substitutes to sugary beverages and soft drinks. It has a prophylactic and treatment potentials. A lot of the benefits of lemon are mentioned in your question. Thank you

  • Roja Raman Mekalathur added an answer in IDL:
    How do I perform IMF analysis to find the harmonics using MATLAB or IDL?

    What is IMF or EMD?

    Where is it actually needed?

    Where can I stop IMFs?

    Roja Raman Mekalathur · Academia Sinica

    I feel IMF and EMD are similar functions. They are generally used to extract the different periodicities and natural forcings like QBO,ENSO, Solarcycle ext hidden in the original time series. For more details follow https://www.clear.rice.edu/elec301/Projects02/empiricalMode/

  • Louis Depasquale added an answer in Elderly:
    Which is the best test to prevent falls in the elderly?

    I need a simple protocol that can be used in large populations

    Louis Depasquale · Good Samaritan at Shervier New York

    TGUT is very do-able but possesses ceiling effects and is not very discriminating nor responsive or sensitive to change at high performance levels. Pardassaney et al, Pai et al, Schoene, Arnold and other recent studies have ID limitations of TGUT in active older adults in particular.  Because a test is "do-able" doe not translate into useful. Perturbation assessment, stepping responses,reactive postural responses need assessment. Developing effective stepping responses at body weight forces of the magnitude of at least 10 % TBW will provide protection against falls.  Individuals 65 years and older should be tested for reactive stepping annually to determine % TBW effective stepping limits in AP directions. In my 40 year experience, RIPPS % TBW measure best ID fall risk and provides  quantitative, serial clinical decision making for older adults. TUGT, Gait Speed,Single limb stand time, Tandem stand time are ineffective measures of fall risk alone or in combination. Add  four square step test Tinetti to that list as well for active older adults.

    I n separate studies, Pai, Martinez, Mille, Carty, Mansfield and DePasquale provide orientation to stepping and perturbation assessment.

  • Farzane Gh added an answer in Circuits:
    Whats the real behavior of rc circuits?

    In series RC circuit with dc power supply the maximum capacitor voltage should be equal to power supply but in my experiments it's less than expected value and it's proportional to resistor, while in theory it's not reasonable. Please tell me your opinions.

    Farzane Gh · Materials and Energy Research Center

    Hello everybody. I should apologize for my late response due to some involvements. but as Cyril had anticipated, in a moment I faced a collection of ideas and it was great. I read them carefully. Thanks a lot for your attention.
    I didn’t use a specific circuit arrangement, But I would explain about my instrument and data. Rectification process was done with a power supply with single phase AC source and as Barrie said, I think the kind of this process is important.
    For measuring capacitor voltage, I used both analog and digital scopes and deviation from ideal values (after 5 time constant) was almost the same. So I think using electrometer, in spite of it’s benefits, is not the final solution in my case.
    Then It seems that I should pay more attention to capacitor leakage resistance as Sujit and the others said. But what’s the range of this leakage in various capacitors and how can I get rid of this loss? With negative resistance theory of Cyril? perhaps ;)
    They are my experimental data in two cases:
    1) capacitor and resistor are both variable and are series with a power supply that I explained.
    C=100 pF
    R=100 Kohm
    V=10 V
    Measured voltage of capacitor by scope (after 5 tao) is 6 V (and this measured voltage was a function of resistance just) So I should conclude that capacitor leakage resistance is 0.15 Mohm If we use this equality: Vc=V*Rc/(R+Rc)
    2) after changing the capacitor I used a ceramic ones and a constant resistor:
    C=0.01 MicroF
    R=0.24 Mohm
    Measured voltage of capacitor was 3.4 V. So capacitor leakage is 0.51 Mohm.
    Are they reasonable values and do you think that just resistance leakage is response of this deviation?