Q&A

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  • Is there any recommended tutorials to teach beginners how to collect and analyse software engineering data?

    Is there any recommended tutorials to teach beginners how to collect and analyse software engineering data?

  • Which are the economic and social development perspectives for Africa within the Millennium Development Goals?

    Donors; Tied Aid

    John Mukum Mbaku · Weber State University

    I am sorry to disagree with you, but the MDGs, like other externally orchestrated policies, do not really have much relevance for a lot of countries or communities in Africa. Newly-developed countries such as South Korea, did not achieve their levels of development by relying on externally developed policy goals. South Korea's development and to a great extent, that of the People's Republic of China, can be traced to internally constructed policies, those that were fully cognizant of each country's specificities, its common historical experiences, its areas of comparative advantage, etc. A country cannot achieve genuine development by relying on externally generated policy initiatives.

    Most African countries follow the MGDs in order to have access to foreign resources and not necessarily because they believe that these policies are necessarily consistent with local values and aspirations. Of course, this is not the first time the international community has tried to impose policy on the African countries. Do you recall the IMF and World Bank initiated structural adjustment programs (SAPs)? Despite the fact that many African governments embraced them with a lot of enthusiasm, they did not provide many benefits for the people. Instead, the people who benefited from them were the elites who were charged with implementing them. The MGDs are not any different. 

    Like the SAPs, a lot of the foreign actors who support the MGDs and actually supply African countries with the resources to implement them are not doing so for purely humanitarian reasons. Perhaps, you are not aware, but there is a new scramble for Africa and many developed countries, including China (PRC), Japan, the United States, and the European Union, as well as South Korea, are seeking ways to improve their trade and investment in Africa. This is the true reason for the renewed interest in partnerships between these external actors and Africa. Such partnerships are not likely to benefit Africa if their definition remains essentially the purview of foreign actors.

  • Which journals or sites are good for looking at dental attrition and dental issues in Egyptian mummies with reference to x rays or CT's?
    I'm looking at dental attrition in Egyptian mummies using x rays, I want to find other examples of x rays that show abscesses, severe attrition. I have found a few mentioning them or showing the odd image but they are mainly non royal. But I would prefer a database so I can have comparison images. If they are not x rays or CT's it's not important, as long as they are royal or elite Egyptian mummies because that is what my research is based on.
    Jaime González-Gómez · University of Veracruz

    Something related...

    http://www.ncbi.nlm.nih.gov/pubmed/19464646

  • R. Judkoff added an answer in Microcontrollers:
    Does anyone have experience with a solar tracking sun position lookup table?

    In some PLC based solar trackers, real-time processing speed is too limited to use astronomical algorithms in high accuracy sun tracking. In precise solar tracking, a lookup table can be pre-calculated and the solar vector values (sun azimuth rotation and sun elevation altitude) stored in the lookup table or spreadsheet. With a pre-established lookup table, a PLC can obtain the position of the sun at any time and then the direction of tracking mechanism is adjusted to point to the direction of the sun, much like tracking preset waypoints in (solar) navigation in a time-synchronous manner. Was hoping researchers can share practical challenges or complications with Eprom type lookup tables in PLC or microcontroller environments.  

    R. Judkoff · National Renewable Energy Laboratory

    I suggest you contact Ibrahim Reda at the National Renewable Energy Lab for an answer to this question. His email is:

    Ibrahim.Reda@nrel.gov

  • Do you think that digital technologies can stimulate an increased interest in reading and writing and or increase the level of literacy within a society?
    In some developed countries, functional illiteracy continues to be a very serious problem, partly due to their crisis in education.. Do you think digital technologies might influence an increase in the level of literacy - particularly among children. In countries where illiteracy has historically been a persistent problem, Book publishers have been making efforts to give their books away to poorer children who have access to the internet because they believe that by introducing children to online stories these children will eventually be encouraged to read 'classical' books.
  • Wes Raikowski added an answer in Linguistics:
    Is human thought a form of internal speech or is it independent of language?
    Can it be that, by necessity, all psychological faculties are innate and learned, biologically restricted and socially constructed at the same time? At the end, the human body is (innately) pre-structured to interact with the world external to it. Is it possible, therefore, that most discussions about Sapir-Whorf hypothesis are just a case of simple misunderstanding?
    Wes Raikowski · Griffith University

    Dear András,

    Thanks for your reply to my comments.

    Re: “As I understand, your standpoint is related to 2D maps defined on a preexistent neural network, organized in sensory modalities (SM) and motor modalities (MM), which can realize a (probable large) number of associations.”

    What is associated are the parts of various sensory maps first within their own modality, then between various modalities. Together they form a network. But this is not the network in your sense (connection between nodes) but the associative network between bits and pieces of various maps each of which codes spatial patterns.

    Re: ‘How do you envisage the formation of these associations?
    By associative (Hebbian) learning.

    Re: “How are these 2D maps evoked and linked in a succession during a chain of thought?
    By means of simulation. This means that human memories and thoughts are not the connections between the neuron cells as such, but the activation of those connections. The chain of thought/memories is a temporal sequence in which the simulations are activated.

    Re: “the processing patterns (PP) are evoked in the cortex as multidimensional structures”

    I devoted a lot of time to the issue of direct coding of dimensions in the brain. The idea of such a mechanism is very attractive – one would be able to perceive 1, 2, 3, and any other higher dimension directly. I concluded that the networks alone cannot represent spatial relationship so essential for living. If we use the distance between nodes/elements as a relationship then no coherent “image” of space can be created. Nocturnal owls provide a convenient example

    ( http://en.wikipedia.org/wiki/Coincidence_detection_in_neurobiology ).

    The neurons are arranged in a way that amplifies the time differences of the sound reaching two spatially separated ears. Detecting a difference alone, however, does not “record” spatial relations for which one would need a map of like elements. Only when the interaural time differences (ITD) are associated with a position of the head/eyes a sense of spatial relations emerges.

    Re: “But the multidimensional approach offers some advantages and flexibility which could be interesting if someone tries to construct a model of the cognitive process.”

    Indeed, the model proposed by you is attractive. But I find it confusing in light of what I know about the nerve system anatomy and physiology. I like simple (simplistic?) engineering explanations like the model of binaural coincidence detection offered by Jeffress.

    Regards, Wes

  • Deyan Ge added an answer in Geometric Morphometrics:
    How could I determine the number of semilandmarks to include in analysis?

    I am trying to analysis a open curve by using semilandmarks, however, the reviewer said that I use too many semilandmarks, and suggest to test the sensetivity for the number of landmarks included in Geometric Morphometric analysis. You know, the number of semilandmarks is different in different dataset, so I could not use Procrustes Anova. I think about ANOVA of PCA scores, bending energy, ect. Would some one please give me some suggestions on this? Thanks!

    Deyan Ge · Chinese Academy of Sciences

    Dear Philipp and Micheal, thanks again for your attention.  For my situation, the start point and end point are easy to localize, they are homologous among specimens, the entire region I want to study has large morphological change, but they are all derived from the lateral side of the same bone in different species. This region is taxonomically and functionally important. In the first version of the MS, I used 148 semilandmarks along this curve and with the start point and end point as fixed landmarks. The reviewer suggested that I need to test out the number of semilandmarks to include  in analysis. I wonder whether there is a better way to digitize this region. And how could I determine the number of landmarks (should I use landmarks, instead of semilandmarks?) been sampled along this region? Thanks again.   

  • Sandeep Gandikota asked a question in Building:
    How to Initiate a change in India for sustainability?

    How does a country like India initiate a change to their perspective from building very affordable and economical houses to building green and sustainable homes?

  • TiO2 target changed colour after pulse laser ablation why? infact it was white but after illumination its colour changed to steel grey?

    i have deposited TiO2 with pulse laser deposition system at room temperature and 10 e -6 pressure infact thin film was fabricated but the target has changed colour from white to steel grey where laser was incident.Can anyone suggest the reason for it? the laser wavelength was 532. 

    Amir Abidov · Kumoh National Institute of Technology

    Vacuum has reducing property. Your target's stoichiometry changed due to formation of oxygen vacancies. Now you have TiyOx non stoichiometric TiO2. Reduced Tio2 can have blue, grey and even very dark colors.

  • If water contaminated by the F, SO4, Na, Mg, Total Hardness and Fe, then suggest me best method (low cost) for the treatment of water ?

    Water Treatment with Low Cost budget 

    Henrik Rasmus Andersen · Technical University of Denmark

    There is no cheap method to treat all these parameters. You have to use reverse osmosis membrane filtration.

    Could you consider if all the parameters are needed. E.g. Mg is very unlikely to be harmful.

  • Shakeel Rehman added an answer in Network Coding:
    Why is the physical layer network coding(PLNC) compared to XOR operation?

    This is a technique performed during relaying. Say, for example, in a two way relay channel or bidirectional relay network the relay performs PLNC. This is given with XOR operation in mathematical expression. At relay, the electromagnetic interference of two nodes causes PLNC. This is what is given in research papers(IEEE Journals).

    Pls substantiate the analogy. How does PLNC relate to XOR?

    Shakeel Rehman · Iqra University

    there is another may be related term ANC analog netwrok Coding. what is the difference between ANC and PLNC. does PLNC is for digital signals?

    if we suppose CSI is available then can we can get other terminal signal for two-way system in which both terminals signals get added with awgn noise at relay terminal we perform XOR and get other terminals signal with awgn in case of Amplify and forward. please correct

  • Amy Maynard added an answer in mtDNA:
    Could someone suggest a good protocol for mtDNA amplification?

    Hi,

    I'm trying to amplify mtDNA but I always obtain very different results in terms of efficiency (most of the time the short fragment is not amplified).

    The primers I'm using are:

    Long fragment (8.9 kb)
    Mitolong_for 5’-TCT AAG CCT CCT TAT TCG AGC CGA-3’
    Mitolong_rev 5’-TTT CAT CAT GCG GAG ATG TTG GAT GG-3’

    Short fragment (221 bp)
    Mitoshort_for 5’-CCC CAC AAA CCC CAT TAC TAA ACC CA-3’
    Mitoshort_rev 5’-TTT CAT CAT GCG GAG ATG TTG GAT GG-3’ 

    Any suggestions will be very appreciated. Have a nice day! Deb.

    Amy Maynard · Missouri State University

    I was using Taq polymerase if it makes any difference. 

  • Selvaraju Sivamani added an answer in Expert Design:
    How to form the optimization by the expert design?

    I've tried to optimize formula of beverage by expert design.

    Selvaraju Sivamani · Kumaraguru College of Technology

    Please elaborate the problem statement.

  • Selvaraju Sivamani added an answer in Social Work:
    Is there any website / citations to get articles for social work research?

    Are there any website / citations to get articles for social work research?

    Selvaraju Sivamani · Kumaraguru College of Technology

    Dear Researcher,

    Please find the link to explore refereed journals in social work research:

    http://ip-science.thomsonreuters.com/mjl/publist_ssci.pdf

    You can search for opt journal and then for articles.

    Best Regards,

    Sivamani S

  • What are the virulence factors of Zaire ebolavirus?

    I am looking for the virulence factors of Zaire ebolavirus to truly understand the nature of the pathogen.

    Juan H. Macías · Universidad de Guanajuato

    I think these paperes could be helpful. Kind regards.

  • As anyone used or know good papers on artificial neural networks as a classification method for work events?

    Hello everyone,

    I am conducting a study in which I pretend to relate work events with emotions and I'm doing so with neural nets. So, as far as I know, I can interpret each hidden node as a "category" (or a factor) where related events group together before generating outputs. It's similar to a classification system, but resorting to a non-linear method. Now, I searched and searched for previous studies that did something similar, regarding classification of events in organizational research and classified them with neural nets but apparently there are none. Does anyone know of enlighting researches that followed this same method?

    TIA

    Ali Chaibakhsh · University of Guilan

    See:

    Fault Diagnosis of Nonlinear Systems Using a Hybrid Approach, Sobhani-Tehrani, Ehsan, Khorasani, Khashayar, Springer, 2009.

    Computational Intelligence in Fault Diagnosis

    Palade, Vasile, Bocaniala, Cosmin Danut (Eds.), Springer, 2006.

  • Thepthida Mounlasy asked a question in Laos:
    Is there any document for the revolution of urban planning change in southeast Asia?

    Currently looking for more  urban planning information in specific country such as Laos. Both information about its history and architectural study in each period.

    Thanks

  • Can anyone send me information about ethnobotanical studies conducted in urban settings?

    I have some funds to study traditional knowledge of immigrant groups in urban settings. The references are scarce.

    María Claudia Luján · National University of Cordoba, Argentina

    Am currently doing a PhD in urban and rural ethnobotany (Córdoba, Argentina). The subject is vast. Specifically you need ??. Sorry my English is very bad. Greetings.

  • Catarina A. Marques added an answer in Gene:
    What does it mean when a gene cannot be knocked out?

    efforts to knock out the msp-2 gene in plasmodium have been unsuccessful.What does that mean with respect to the gene?

    Catarina A. Marques · University of Glasgow

    Hello, Plasmodium is haploid, so only one allele to KO. I guess if several strategies are employed and you can't ever get a KO it might suggest that the gene is essential. The problem is that it is never the most convincing way of saying "it is essential", you are never 100% sure if the parasite can't live without the gene or the transfection rate is too low, or something went wrong with it. And the problem in Plasmodium is that you transfect the parasites in the blood stage, and an essential gene in that stage might not be so in the other stages. I would look at papers that have been successful or attempted KO genes for more info. Also, I think that there are some groups working on conditional KO systems, I would take a look at them as well. Good luck.

  • Selvaraju Sivamani added an answer in Xylose:
    What methods are best for quantifying glucose and xylose a broth culture?

    I am doing research on bioethanol production from xylose but HPLC is not within my reach for now. I want to know which other methods are good for quantifying glucose and xylose in the mixture of the two (cofermentation).

    Selvaraju Sivamani · Kumaraguru College of Technology

    Dear Reasearcher,

    I suggest you to use orcinil method for xylose and GOD=POD for glucose estimations.

    Best Regards,

    Sivamani S

  • Ahmad Basirul Subha Alias asked a question in Abaqus:
    I have a quick question about the modeling simulation using ABAQUS. How can I model the interaction and contact properties for the bolt-nut fixture?

    I have this one cylindrical steel chamber, and have to load its internal surface with simultaneous thermal-mechanical stress (The chamber wall model is attached). What I want to look at is the effect of these stresses at the interface where different materials i.e., the steel and fused quartz (the material for the optical window) meet, as well as the temperature distribution across the chamber thickness.

    Therefore, I need to model the interaction properties for the two materials in contact, and also I need to precisely model the interaction for the bolt-nut fixation surfaces in order for me to quantify the level of tensile stress experienced by each bolt-nut fixture during the loading.

    Anyone who are familiar with interaction modelling in Abaqus could please lend me a hand on this? I am very sure that your expertise with respect to my particular problem here is second to none!

    Thank you in advance.

  • Martin Forde asked a question in Ethanol:
    Great siRNA transfection efficiency, but no knockdown with validated positive controls?

    I'm performing reverse transfection on SH-SY5Y using Viromer Green, and I get wonderful transfection efficiency (90+%). See picture (RFP labeled siRNA fluorescence overlapped on phase contrast image).

    However, when I qPCR for KO I see no knockdown for any of my siRNAs. It's odd, because I had previously validated this protocol for two of my siRNAs and they worked fine (>50% KO with low standard errors, replicated across multiple biological replicates, at multiple time points, with a clear and significant dose response curve). So I know that at-least two are targeting my transcript fairly well.

    For qPCR, I'm using TaqMan chemistry with best coverage primer probe sets. I'm extracting total RNA with Directzol (column-based RNA separation from Trizol reagent), and cDNA synthesis with MultiScribe.

    Almost everything in my protocol is identical to what I performed in the validation. The only thing that is different is that I forgot a step in the RNA extraction process. In particular, Directzol indicates to homogenize cells in Trizol, add an equal volume of ethanol to the homogenate, run through column, several ethanol washes, and elute in water. This time around, I forgot to add ethanol to the homogenate. Stupid move on my part, I know. Obviously, it precipitates the nucleic acids out of solution, so that they more readily interact with the column. However, I still recovered a good deal of pure RNA, which was lower though roughly consistent with my yields from the validation. So I reran my extraction protocol with the ethanol addition and my yields were somewhere between 1.5-2x greater. 

    My question is would this necessarily be a causative issue with the lack of KO in the TaqMan experiment? I'm testing this hypothesis in the next couple days, but I would like your input to see if this reasoning is solid. If it's not then maybe I can save some reagents. I just find it odd that I got a decent quantity of high quality RNA from the extractions without the ethanol precipitation. Plus, when I run the cDNA from these batches I still get good amplification curves (all thresholding between 15-25 cycles) with little variability between technical and biological replicates. So I don't think it's an issue with cDNA synthesis or the assay itself. Could the lack of ethanol precipitation bias my pool of total RNA? Wouldn't any bias that results from RNA loss in the extraction process be relatively random? In turn, shouldn't I still be able to see my KO effects at the mRNA level? Or could the lack of ethanol precipitation cause the total RNA pool to be of lower quality? I've ran samples on both nanodrop and qubit, and both my 260/280 & 260/230 are consistently between 2-2.1.

    Any ideas or questions to help me work through this would be greatly appreciated?

    Marty

  • Dorian Aur 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.

    Dorian Aur · Stanford University

    Don't you think there would be a major ethical issue?
    Any type of real progress raises (more or less)  new ethical issues. Even building cars raised major ethical issues see http://en.wikipedia.org/wiki/Locomotive_Acts quite different than ethical issues today , e.g. global warming.

    One can build Frankenstein, I prefer a different version where such machine would be "laughing of the mechanic aspects of its being" see Louis Brassard 
    https://www.researchgate.net/post/Can_we_build_a_conscious_machine

    Could you do this without knowing the mechanisms of the paradigm?
    Clearly, we cannot do it using digital computers, we do not have "the algorithm" and we might not have anything in the next fifty years since  consciousness does not appear to be computable see arXiv:1405.0126
    What I'm proposing is just to use "the physical mechanisms" it can be done fast, a reliable solution to instantiate conscious states. Please read http://dx.doi.org/10.13140/2.1.2286.5608 Questions and Answers part

    Importantly, we didn't try Sputnik, man on the moon, Higgs, internet just to display our knowledge about physical laws 

    A conscious (intelligent) machine would not be just  a scientific  breakthrough (e.g. Higgs particle) it has  many useful applications see the manuscript  Q&A part http://dx.doi.org/10.13140/2.1.2286.5608

  • Elizah Nagombi added an answer in Chytridiomycota:
    Who can provide chytrid fungus isolates?
    I'm an MS Biology student from the Philippines and currently working on chytrid fungus in frogs. I would like to ask who/which laboratories can provide Batrachochytrium dendrobatidis isolates for students/researchers like me? If possible, what are the necessary actions or requirements I would need to prepare for this matter?
    Elizah Nagombi · New Guinea Binatang Research Centre

    Our swabs sample from Papua New Guinea are sent to South Australian Museum for checking of the fungus. You can try contact Steve Richards there for any chances of collaboration. Best, Elizah.

  • What is a suitable culture media for ethanol production test and a reliable biochemical method to estimate the produced ethanol?

    We are working on yeast isolates and are interested to screen high ethanol producing isolates. Since the number of isolates is quite high ( >200), it is not possible for us to analyze the whole set with GC-MS. Hence we are looking for a reliable biochemical method to separate high ethanol producing isolates first, later, which will be subjected to GC-MS analysis.

    Kindly note, the potassium dichromate and sulfuric acid method [Caputie A, Ueda M, Brown T (1986). Spectrophotometeric determination of ethanol in wine. Am. J. Enol. Vitic, 19:60-65 ] is not effective at our current laboratory environment, and hence cannot be adopted. If anyone can suggest any other methods, it would be a great help.

    Thank you.

    Selvaraju Sivamani · Kumaraguru College of Technology

    Please find the attached file:

  • Mannan Nouri added an answer in Dyes:
    How does CyQuant Direct compare to CyQuant NF? Could somebody please share their experiences?

    I am contemplating using a CyQuant line of dyes from Life Technologies (LT). But there are two types which are confusing me: CyQuant Direct and CyQuant NF. From their description, the only difference seems to be that the Direct needs the removal of a supernatant in a well-plate format. I was further confused by a tech rep from LT who told me CyQuant just gives you a total count of live and dead cells, contrary to what I read in the description.

  • David Harris asked a question in Biomimicry:
    How can biomimicry significantly improve global sustainability in urban design?

    Time is constant, but our earths resources are not. Over 4.5 billion years our natural environment has existed on planet earth yet we must adapt to climate change and a growing global population. Using nature as a model, we must adapt and change our mindset and attitude in response to architecture and urban design.

    Biomimicry may have all the answers... how?

  • Tina W Wey added an answer in Behavioral:
    Is there a database for behavioral datasets?

    I was wondering if anyone could suggest a data archiving equivalent to GenBank or TreeBASE for the storage of different types of behavioral data (e.g., activity budgets, social networks, diet, track logs); both as a source for comparative data, but also as means of storing data for the long term after publication. Thanks in advance for any suggestions,

    Jan

  • Micronucleus assay performance?

    Why is fetal calf serum necessary for this assay? When performed from bone marrow why do the cells need to be re-suspended in FCS? The methanol fixation is done after smears are made...so I don't see the point of using FCS! 

    Nikola M Stojanovic · University of Niš

    Dear Raymond thank you for your answer.

    Im using mice for this test and i have tried to do it with HBSS-BSA and with citrate solution. The HBSS-BSA worked fine (in control groups) no cell were attached to each other on the opposite all that happened in citrate solution.

    I have stained the slides with both Giemsa and Feulgen method and I just  glanced on those slides...didnt have time to devout to detailed analysis jet! But thank you for the guides and I will read the paper before further experiments most certainly. Also fluorescent dying is to expensive for our conditions for the moment.

  • Reginald L. Bell added an answer in Back:
    Can the reviewer request new additions or amendments to the article before publication?

    After doing all the amendments requested by reviewer, and after sending the article back to the editor. Does the reviewer have the right to request new amendments to the article?

    Reginald L. Bell · Prairie View A&M University

    I believe it is possible to find flaws in any published work. Therefore, at some point in time the editor must be brave enough to draw the line and publish an article that has been accepted for publication. The authors bare the risk of criticisms once the work is published. After a certain point, requests for major changes are unreasonable.