Q&A

ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

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  • Bimo Hernowo added an answer in Architectural History:
    In your opinion, what is the best book on "History of Cities"?

    I like very much the book (1980) "The History of the City", MIT Press by Leonardo Benévolo, but I would like others indications.

    I thank if  are also suggested books on the history of specific cities.

    Thank You very much.

  • C. Lewis Kausel added an answer in Work-Environments:
    Does technology have a role in influencing the Quality of Work Life (QWL)?

    The QWL as strategy of Human Resource Management has assumed increasing interest and importance.There are divergent views as to the exact meaning of QWL.

    QWL is viewed as that umbrella under which employees feel fully satisfied with the working environment and extend their wholehearted cooperation and support to the management to improve productivity and work environment.

    With technological developments , the work place has changed drastically , so also the  life of employees  . Do you feel  QWL has changed?

  • Oleg B. Gadzhiev added an answer in Transition:
    Why has an error happened to find the transition state using qst2 ?

    Hi everyone

    I have a problem to find the transition state from molecule cjycoo-cdo to molecule ycoc(oj)-cdo. My calculation taken 7 hours. but finally error happened. Below are my input and output files. Can I get some valuable information from my output file ? and how to find my TS structure? Thank!

    Bruce 

  • 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

    Marc:

    "Then, you seemed not to comment the rest of my post."

    There is no "seemed", it is quite obvious.  ;)

    "What I deduce..."

    Might I add incorrectly?   ;)

    "...that you are happy to denigrate my saying when you disagree with it but never admit that you agree with me when it is the case: I wonder why?"

    Marc, there is a huge difference between disagreeing with someone about their ideas and denigrating them. I have tried to clarify to you earlier how I always keep that distinction in my mind but somehow you cling to the notion that a disagreement with your ideas is a personal insult to you. We obviously evaluate things quite differently. As a solution to this problem, I only see one realistic option: not to comment on your posts at all. Ask and I shall stop.

    If do not comment on your posts (or portions thereof) with which you feel that I should have agreed, please do not get your overactive imagination in high gear. There is no grand schemes or fiendish plots - try to relax a little!  ;)

  • Sizyoongo Munenge added an answer in SPSS:
    How do i Import Data from Excel into SPSS ?

    Im trying to import data from excel sheet  to SPSS but its failing. 

    The response am getting is "text value unmapable in the current server locale.

    Thanks in advance

    Sizyoongo Munenge · Belgorod State University

    Katrien Oude Rengerink ·

    Thank you so much

  • Vivek Patel asked a question in Dimethyl Adipimidate:
    What is the protocol for for crosslinking proteins using Dimethyl adipimidate?

    we are planning an experiment where we crosslink the protein complex in neuronal cultures and want to run them on gel. Does any one have experience with Dimethyl adipimidate and its protocol. I tried looking up but could not find anything.

    Thanks

  • Armando Nappi added an answer in Functional Morphology:
    Can you suggest papers about skull functional morphology?

    I'm searching papers about functional morphology of mammals skull.

    Can anyone help me? Thanks Armando

    Armando Nappi · Museo civico di Storia naturale, Italy, Morbegno

    Functional morphology and food, more specifically

  • Marcos J. Montes added an answer in Atmospheric Correction:
    How to calculate FWHM values for Hyperion data?

    I am using FLAASH module in ENVI software for atmospheric correction of Hyperion data. It asks about FWHM values which I am not sure how to calculate. I have an ASCII file and in the first column I have given the wavelength values. In the second column, I am supposed to give FWHM values. How to do that??

    Marcos J. Montes · United States Naval Research Laboratory

    One source of Hyperion FWHM is at the USGS web site; see, for example 

    http://eo1.usgs.gov/sensors/hyperioncoverage

    or

    https://eo1.usgs.gov/documents/Hyperion_L1G_EO1-DFCB.v.1.pdf

    Depending where you got your Hyperion data (and whatever processing you've already done., such as removing bad/uncalibrated bands), you may need to edit the list to include only the spectral channels that are present

    So, you'll need to copy the values from one of the sources above, and add it to the ASCII file with the wavelengths. And, of course, make sure the units are whatever is required for your software, usually wavelengths and FWHM both in micrometers or both in nanometers.

  • Carlos Enrique Acuña Escobar added an answer in Higher Education Research:
    How are faculty using the Bloom's Digital Taxonomy in higher education?

    The original Blooms taxonomy has been revised and an additional Digital taxonomy has been developed to accommodate for the integration of technology in today's 21st Century classrooms (F2F and online). But how are faculty using the digital taxonomy in delivery of their technology-enhanced learning and teaching?

    Carlos Enrique Acuña Escobar

    Here they go.

  • Jan Philip Kraack added an answer in Spectrometers:
    Do UV-VIS spectrometer take care of reflectance?

    Trying to obtain absorption coefficient from absorbance data. (HP 8453 Spectrometer). When a UV-VIS spectrometer measures absorbance as

    A = log10(I0/I)

    how does it determine that the loss in the intensity of light is only because of absorption?

    Is absorbance a true measure of absorption?

    What happens to the absorbance when a sample is mostly reflecting so most of the light is reflected back to the source rather than to go towards the sensor?

    Do UV-VIS spectrometers have this reflectance correction?

    Jan Philip Kraack · University of Zurich

    When you measure the absorbance of for instance a dye dissolved in a liquid, measured in a cuvette, what you do in the simplest way is (i) to measure the cuvette with the neat solvent and take the intensity as I0 and (ii) measure the dye dissolved in the same liquid in the same cuvette and take it as I. Despite the fact that you have reflectances at each interfaces, these do not matter because you do the measurement two times and calculate the ratio. 

    However, when you do a measurement of a solid sample, e.g. trying to measure the pure absorbance of the cuvette itself, what would be done is soing the two measurements with and without cuvette. Here, you have the reflectances at the interface only in one measurement, so what you actually calculate is not true/total absorbance. However, you can correct the spectrum for reflectance if you assume normal incidence and you precisely know the refractive indey of your material, e.g. silica. The spectrometer does not correct for reflectances automatically.

  • Vahid Nasiri asked a question in Leishmania major:
    Could anyone take ocular leishmanisis?

    Dear researchers,

    I have a question about accidental leishmaniasis !

    The Last day I was working on my recent experiment on a new vaccine against cutaneous leishmaniasis and unfortunately I do all of my research steps lonely ,thus , when I was injecting live stationary pathogenic leishmania major to foot pad of BALB/c mice suddenly some drops of parasites suspension Sprinkled from the syringe to my eye!

    I washed my eye immediately, but I want to know that I can take ocular leishmaniasis!!

    It seems impossible because the eye environment condition is not suitable for this parasite, but, I want to know your opinion.

    Thanks for your comments.

    Best

    Vahid

  • Imre Horvath added an answer in Reverse Engineering:
    How can we measure the performance of reverse engineering?

    The performance of reverse engineered system

    Imre Horvath · Delft University Of Technology

    I am pleased to share these seminal papers with everyone interested:

  • Robert Shuler added an answer in Riemannian Geometry:
    Why didn't QM and gravitation merge yet?

    I've read in a very interesting paper of Prof. Norbert Straumann

    "Einstein’s impact on the physics of the twentieth century"

     reporting:

    ___________________________________________________________

    In the work of Yang and Mills (1954) GR played no role. In an interview

    in 1991 Yang recalled:

    “It happened that one semester [around 1970] I was teaching GR, and I

    noticed that the formula in gauge theory for the field strength and the formula

    in Riemannian geometry for the Riemann tensor are not just similar

    – they are, in fact, the same if one makes the right identification of symbols!

    It is hard to describe the thrill I felt at understanding this point.”

    (Zhang, 1993, p. 17)

    ___________________

    According to this affirmation the structure of the Macro and MIcro are similar and both follow Geometrodynamics. Why didn't they merge in a unique equation then?

    They definitely individuated a background which allows everything to happen (the ACTION)Higgs field, space-time, but according to the results they didn't manage to describe it well enough yet...  it might be due also to the fact that both of them describe time reversible laws, GRT is a classical deterministic theory... Where is the Arrow of time???

    Robert Shuler · NASA

    Stefano, I just didn't see the answer posted by anyone as to what the difficulties are.  In each of the numerous areas in my survey (which included some I was not previously aware of, like N=8 gravity), the difficulty in another one is cited as justification for efforts.  Looks like that could go on forever in a circle if no one considers them all at once.  I thought that was what you were asking ... what is THE difficulty, not just for one particular approach.  I have not given that answer, of course.  I just summarized what each said about the others as justification for their own work.

    As far as Lorentz invariance, in the previous post I pointed out it is not applicable to gravitational "interactions" which can only occur through non-Lorentz spacetime curvature.  AND, that particle theorists are generally ignoring it (by ignoring the no interaction theorem).  So they do allow evolution.

    I did notice that only one approach, loop quantum gravity, even remotely considers how space-time might be constructed.  It is not a big object in quantum gravity research, and for all but one group not even a little one.  I did not mention Verlinde's theory, because it has gained no more traction than various unnoticed postings by wanna be's such as myself here on RG, but he "may" pay some attention to this goal.  Mostly the objective is to predict scattering results which could be tested in an accelerator or in the natural environment (via CMB for example), without regard to how these might add up at a large scale to make space-time.

    I was just trying to dig up helpful background information for the question, and your question does interest me.  If it is not helpful to you, ignore it.  : )

  • Hediye Erdjument-Bromage added an answer in Outlier Detection:
    Does someone have (a) data set(s) with replicate measurements (spectra) for the same water sample?

    To test several methods of outlier detection and share the results.

    Hediye Erdjument-Bromage · Memorial Sloan-Kettering Cancer Center

    Hi Mathieu,

    Are you thinking of elemental measurement with ICP-MS?

  • David L Morgan added an answer in Questionnaire:
    Can Cronbach's alpha be used to set up a threshold in order to drop items in questionnaires?

    I am currently working on a project regarding to the relationship between physical ability and levels of dementia. We are using different questionnaires to evaluate the levels of dementia. We want to compare the reliability between those questionnaires using cronbach's alpha and further dropping some  redundant items. 

    For example, we have the cronbach's alpha increased by 0.1 if we dropping 1 item form the questionnaire. How can we implement the distribution of cronhach's alpha to conclude that the dropping is valid?

    David L Morgan · Portland State University

    Alpha is a measure of reliability. Retaining an item that would lower the reliability of the scale means the scale would have more random error than if the item were omitted.

    In particular, alpha consists of only two quantities: the average correlation among a set of items and the number of items that go into that average. If alpha goes up when an item is deleted, that means that average correlation among the remaining items is notably higher than the average of the full set that includes that item. 

  • Katrin Domsch added an answer in Chromosome Conformation Capture:
    Can someone explain the differences between the different 'chromosomal confirmation capture' technologies (3C vs 4C vs Hi-C)?

    .

    Katrin Domsch · Universität Heidelberg

    I just know this good review: Wit and Laat, 2012, A decade of 3C technologies: insights into nuclear organization. 

  • Edem Utibe added an answer in Lignocellulosics:
    How does DTG give the information of lignocellulosic constituents in biomass?

    Nowadays, lignocellulosic composition can be determined by using thermogavimetry analysis. However, there is some limitation on it, for example lignin information cannot be obtained. On the other hand, we also can perform a wet chemical method to obtain more reliable result. My question is which method is suitable? Is it better to perform both wet method and TGA method? How does DTG can give the information of lignocellulosic constituents in biomass?

    Edem Utibe

     DTG  curves  (obtained from thermogravimetric curves) are frequently applied to biomass to evaluate pyrolysis kinetics.There is usually  a qualitative conformity between t he; hemimicellulose, cellulose and lignin decomposition and the peaks values seen in the DTG curve

  • Peter T Breuer added an answer in Semigroup Theory:
    Does anyone know what the following type of languages are called (A language is a subset of the free monod A* over a finite alphabet A)?

    A language L over a finite alphabet A is any subset of A*, where A* is the free monoid generated by A. (A* can be identified by the set of all words over A, including the empty word.) Imre Simon defined piecewise testable languages using the congruence relation ~as follows. A language L  over a finite alphabet A is piecewise testable iff for any words v and w in A*, v ~m w implies that v is contained by L if and only if w is contained by L. (The definition of the congruence ~m I don't include here.)

    I am just wondering if anyone knows about whether there exists any terminology to describe those languages, which have a modified version of the above property. Namely, is there any name for those languages L over a finite alphabet A, which are such that for any words v and w in A*, if v ~m w and the first letters of v and w, respectively are identical then v is contained by L if and only if w is contained by L.

    Peter T Breuer · Birmingham City University

    The difference appears to be that the set of "length-m subwords" is itself larger, if one takes subword in the generalized sense. 

    But once one gets down to smaller size subwords in any sense, they don't discriminate (for in or out of the language) at all for a word of length at least length m, since the decision is already made on the length-m subwords .. in whatever sense one is using the term.

    And the words of length less than m are just a finite list, so I don't see that one has to worry about them overmuch.

    The point, I think, is still that one can decide whether a word is in the language or not by looking to see if it has one of a certain finite set of length-m subwords (whatever sense one has for the term), if it is of length at least m itself. And if it is of length less than m one can check with the finite list.

  • Mahdieh Akbari asked a question in AVR:
    Which resource provides clock pulse to AVR timers if CS02-00=6?

    Which resource provides clock pulse to AVR timers if CS02-00=6?

  • Fikrat Hassan added an answer in Love:
    Are there a drawbacks or problems of the love to the family, relative, and friends?

    The natural life need the love with  the people that live with you, in the house , work, town , friends, and relatives. Sometime, some of them , lovers or relatives or friends,   try to take advantages and achieve gains by exploits the relations with you without the right. As a result, your lover, relatives, or friend become a burden to you.

    Fikrat Hassan · University of Baghdad

    I think the love brings safety life and make your work more actively. Confront people with love and smile make life easier for you instead of annoyance. Without wrath possible that peace reigns.

  • Tushar Kanti Ray added an answer in ARIMA:
    What are the definitions and differences between "Precision" and "Accuracy"?

     Accuracy means getting a result that is close to the real answer. Precision means getting a similar result every time you try. But there is still ambiguity in the usage of terms "Precision" and "Accuracy" in English.

    Suppose we want to select among different models (say ARIMA and ANN) for forecasting certain time-series data using some criterion (e.g., RMSE, MAE, AIC, R, etc.). It generally reduces to a comparison of errors between the two models using testing data! So, in such applications:

    1) Which criteria is more appropriate to use?

    2) Are we talking about a measure of precision or accuracy here? 

    Tushar Kanti Ray · State University of New York Upstate Medical University

    As far as my understanding goes I agree with you totally on the  differences existing between accuracy and precision.that you initially mentioned. Thank you. Tushar

  • Jennifer Gibbons added an answer in RNA:
    How to calculate the concentration of miRNA?

    once we have isolated total rna using kits like mirVana , we use total RNA as starting material for cDNA synthesis.But it won't give the concentration of miRNA in the isolated total RNA. So, how should we calculate initial miRNA template concentration so as to interpret qPCR results accurately?

    Jennifer Gibbons · United States Army

    Generally small RNAs (including miRNA) is 10% of the total RNA yield. I would calculate that from your total RNA yield. The only way I know to determine the "miRNA" (in reailty small RNA) concentration is to isolate the small RNA, then do OD260.

  • Joydeep Pal added an answer in Gonadotropins:
    Does anyone know what a suitable hormone to reproduction koi fish is? And what dose should be injected?

    Ovaprim or HCG or gonadotropin.

    Joydeep Pal

    OK the dose calculation is like this :

    W (in kg) X0.5 mL/kg = mL of Ovaprim required or

    W( in lbs) X 0.5 μL/gram = μL of Ovaprim required.

    Cheers Javed!

  • Sergei Sergeenkov added an answer in Inversion:
    What can MOKE technique tell us about conventional and unconventional superconducting materials?

    It is well-known that the symmetry of the nonlinear optical susceptibility is strongly affected by a magnetization or an external applied magnetic field. Thus it is of considerable interest to extend the symmetry analysis of the nonlinear magneto-optical response to the superconducting state for different symmetries of the superconducting order parameter. A symmetry dependent contribution to the magneto-optical response without tunneling contact results in optical second harmonic generation. Although it is, due to the gauge invariance, impossible to measure the phase of the superconducting order parameter without tunneling contact, it is still possible to measure its symmetry, not solely its magnitude. Due to the surface sensitivity of nonlinear optics for systems with bulk inversion symmetry, one can take advantage of the broken inversion symmetry at the surface. This is of interest, because Cooper pairing, together with the always present spin-orbit coupling, is then no more purely singlet- or triplet-like. The interference of the singlet and triplet pairing states, which is linear in spin-orbit interaction, leads to the symmetry sensitive contribution of the nonlinear optical response for systems in an external magnetic field. Can anyone illuminate me more about this?

    Sergei Sergeenkov · Universidade Federal da Paraíba

    Artur, it's a good one.

  • Adel Eldenglawey added an answer in Semiconductor Physics:
    How difficult is to measure the temperature dependence of energy gap in semiconductors?

    I have found there are experimental references on temperature dependence of the energy gap in semiconductors. How difficult is to measure this experimentally and how relevant is this for the semiconductors community? What about measurements in ultra-thin layers such as graphene?

    Adel Eldenglawey · Taif University

    Please check the attached file

    the web site of this chapter is:

     http://www.amazon.de/Structural-optical-electrical-properties-As-Se-Tl/dp/3844398430

  • Jennifer Gibbons added an answer in RNA Yield:
    Can someone help me figure out why I got RNA Yields <10ng/ul using miRNeasy Kit?

    I am using the miRNeasy kit to extract RNA from PMBCs stored in RNAlater.

    Cells are pelleted at 300g, Supernatant containing RNA later is removed and cell pellets are flash frozen on dry ice, before proceeding with addition of lysis buffer and homogenisation.

    I know the protocol says perform the phase separation at 12000xg, 4C, however we do not have a chilled microfuge capable of these speeds. I have tried it at room temperature at 12000xg and at 4C at 5000 xg. The phase separation has seemed fine, as i have been able to obtain an aqueous phase with no issues.

    I have attempted to increase my final concentration by warming up my RNase free water for eluting out the RNA from the column, reusing the elute from the first elution a second time to increase concentration and allowing the RNase free water to incubate for 10minutes on the spin filter membrane.

    On a few sets of extractions I have accidentally used the column and reagents from the RNeasy Mini kit instead of the miRNeasy kit, while still following the miRNeasy protocol, replacing Qiazol with Buffer RLT and RWT with RW1. I cant understand why these have given fairly good yields. but the miRNeasy kit is giving me a majority under 10ng/ul.

    Any help would be greatly appreciated, particularly with regard to how to perform the phase separation step and why RNeasy is giving me such substaintially better results.

    Our service user would prefer to also obtain miRNAs so just switching the RNeasy isn't a great option, but if its all we can do, it is all we can do.

    Thanks in Advance

    Jennifer Gibbons · United States Army

    miRNeasy would purify small RNAs, whereas RNeasy can purify total RNA. Small RNAs are ~10% of the total. So, is your miRNeasy yield ~10% of the RNeasy yield? If so, that is normal.

    Hopefully Qiagen tech support can give you a detailed answer. I know in general the only difference between purifying small RNA and total RNA is the alcohol concentration during column washes.

  • Katrin Domsch added an answer in Gene Knockout:
    How do you select for single and double knockout in the Crisper/CAS9?

    We are planning a gene knockout experiment using origene gene specific crisper knockout. We were wondering of the best way to select for double knockout without doing southern blot? will FISH do it or do you have a better way?

    Thanks

    Katrin Domsch · Universität Heidelberg

    You can also try a T7 endonuclease I assay to identify which of your lines contains a mutations. And finally I would also recommend sequencing.

  • David L Morgan added an answer in Qualitative:
    Is it possible to set hypothesis for qualitative data?

    in the process of analysing data collected, it was discovered that all are qualitative and contemplation is on to state and possibly test hypothesis

    David L Morgan · Portland State University

    I agree that one would not begin with hypothesis if the goals of the research were exploration and discovery, but not all qualitative research has to pursue those goals.

    As for using hypotheses, I mentioned earlier that one could begin by predicting patterns that would or would not be present in the data. For example, if are you indeed interested in meaning, then you might predict that men and women will assign different meanings to the same event. Or, if you are doing comparative case studies, you might predict that a given set of factors will have more influence in one set of sites than in other sites.

    I also agree with Jochen that "We always work with assumptions about our empirical object, some of which are theoretical... Making them explicit and being ready to overturn them any time is a good way of starting any research project, including a qualitative one." No one enters the research setting as a blank slate (tabla rasa), so it is rather better to be reflexively aware of one's prior assumptions, and many of those assumptions can easily be stated in the "if... then... " format of hypotheses.

  • Jabar H. Yousif added an answer in Traffic Accidents:
    Is there any database or sites that offer car accident data?

    Number of the studies discusses the role of information technology in the prevention of car accidents in order to reduce the number of accidents through data analysis and to find effective solutions to ensure reducing the loss of life and equipment. How we can get like this data which include the number of car accident in world and its factor.

    Jabar H. Yousif · Sohar University

    Thanks yusuf for your answer.

    regards

  • Ramona Vijeyarasa added an answer in Social Transformation:
    From a feminist perspective, how is it best to understand both waged and unwaged women's work in contemporary financialised capitalism?

    Especially, social transformations with respect to social reproduction—including transformations to the measurement and valuation of domestic labor.

    Ramona Vijeyarasa · University of New South Wales

    Hi David, You may be interested in some of the work that ActionAid has done on women's unpaid care work and time use diaries to measure and value this work. You can read our report Making Care Visible here: http://www.actionaid.org/publications/making-care-visible

    Best wishes,
    Ramona