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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  • Jerson Mosquera Pretelt added an answer in Gaussian:
    How can DFT calculation from gaussian contribute to my research about doping TiO2?

    Can DFT calculation from gaussian predict or explain the result of doping from TiO2 with metals?

    Jerson Mosquera Pretelt · University of Antioquia

    I want to calculate nanoparticles.

  • Abdullah A. Mohamed added an answer in Security:
    I aim to design on-line IDS by using nsl-kDD data set. is there any way to extract the features of NSL-KDD from a real packet?
    NSL-KDD features consist of 42 features, divided into three classes TCP header, domain and 2-Minette connection. The first type is extracted easily, but the last tow type i can't seem to get. Is there any tool, program language lib. C#.net or other that could be of help?
    The feature is shown below.
    10 hot no. of hot indicators
    11 number failed logins no. of failed logins
    12 logged in (discrete)
    13 number compromised no. of compromised conditions
    14 root shell
    15 su attempted
    16 num root no. of root accesses
    17 num file creations no. of file creation operations
    18 num shells no. of shell prompts
    19 num access files no. of operations on access control files
    20 num outbound cmds no. of outbound commands in an ftp sessionc
    21 is host login (if the login belongs to the hot List)
    22 is guest login
    23 count no. of connections to the same host as the current connection in
    24 srv count no. of connections to the same service as the current connection in the past two seconds
    25 Serror rate % of connections that have SYN errors
    26 srv Serror rate % of connections that have SYN errors
    27 rerror rate % of connections that have REJ errors
    28 srv rerror rate % of connections that have REJ errors
    29 same srv rate % of connections to the same ser-vice
    30 diff srv rate % of connections to different service
    31 srv diff host rate
    32 dst host count
    33 dst host srv count
    Abdullah A. Mohamed · University of Mosul

    thanks Mr. Mahdy. I will.

  • Eugene Khaskin added an answer in Ligand:
    Can two Pt(IV) complexes exchange chelating ligands?

    In other words, can the following reaction occur?

    (L1)Pt1(IV) + (L2)Pt2(IV) -> (L2)Pt1(IV) + (L1)Pt2(IV); where L1 and L2 are two similar chelating ligands and Pt1 and Pt2 are two distinguishable Pt(IV)-centers.

    Any references would be extremely helpful

    Thanks!

    Eugene Khaskin · Okinawa Institute of Science and Technology

    Yeah, they are chelating ligands; it would be pretty hard to have non-chelating aryls or alkyls as ligands. The Pt(II) is d16 and has some empty coordination sites. It probably attacks the Pt(IV) ligand. It might be analogous to a simple SN2 reaction if the geometry allows. You should take a look at Julia's papers with Mirica and Tobias Ritter's work on Pt(III) mononuclear complexes and dimers respectively. They can disproportionate to Pt(II) and Pt(IV) and this is probably how the exchange of ligands happens. There is Me coupling that occurs there too, to give ethane, but that's a bit different. 

  • Can I get help with the identification of this silkworm pest?

    A new pest observed in Soalu - a food plant of muga silkworm in Kalimpong hills. I request  help for identification of the pest. 

    David J. W. Morgan · California Department of Food and Agriculture

    Could be Gibbovalva quadrifasciata. see https://www.flickr.com/photos/bettaman/3961181890/ and eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/9845/1/40_p1-133.pdf

  • Huda Atiya asked a question in Cell Line:
    What is the maximum volume of 4T1 cells into the mouse mammary gland by intraductal injection?

    I am reading about 4T1 cell line and I want to know how much can I inject intraductally without causing any damage for the network.

  • David Spector added an answer in Anxiety Disorders:
    Chronic stress leads to anxiety or depression?

    Chronic stress can lead to anxiety in some people, while it can lead to depression in others. Some people with chronic stress may experience both anxiety and depression. It seems not clear how stress, anxiety, and depression contribute to each other. How can we interpret these different combinations of co-morbidity?

    David Spector · Natural Stress Relief, Inc.

    Mariam Ahmad, while I agree with your conclusion, some of your statements are in error, and readers should not accept them as fact.

    "While chronic stress like PTSD is considered lifetime and life threatening disorder with no hope of leaving the mental institution,"

    This is most certainly incorrect. Current research in PTSD is showing dramatic benefit, both for outpatient maintenance and for actual cure, by the mental technique known as transcending, specifically as taught by the Transcendental Meditation organization (I have no relationship with TM). CBT, which you also mention, has had some (but limited) success in treating PTSD. Also, peer support groups are helpful in maintenance of PTSD. This is not a disorder that necessarily requires a lifetime of incarceration in a mental institution.

    "The person undergoing depression is most likely to be put under ECT in not once but daily therapy."

    This statement, also, is completely incorrect. ECT is only one of many effective interventions for the various forms of depression. It is most effective for drug-resistant depressions, where it frequently provides rapid and lasting relief. For most patients, it is more appropriate to start with a mix of psychotherapy and antidepressant medication. This is well-known information, so your mistakes are really not excusable. I say this with respect, but with deep concern that your statements might be taken by some readers as authoritative.

  • Salina Abdullah added an answer in Teaching Methods:
    Can anyone share with me your experience or any related information on framework-based teaching of ifrs?

    best teaching method? sources of information?

    Salina Abdullah · Universiti Teknologi MARA

     Hi! thank you for sharing. really appreciate it..i will try to check later..

  • Ramon Quintana added an answer in Bureaucracy:
    How might responsible decision making be encouraged?

    How might responsible decision making be encouraged?

    It seems universal and timeless that for any organization, people who 'rise' to positions of authority and management are very often ill-equipped to perform their functions.  They often are very vague or even clueless regarding the best goals of the organization. Being proficient at obtaining power does not appear to correlate well with knowing how to perform one's responsibilities. This is often seen in industry, government bureaucracy, politics, and I would suspect in laboratory management and in any other organization one might care to name. It's an unfortunate circumstance of the human condition. (Unfortunately I would also have to add irresponsible leadership in religious organizations in this problem as well.  We often do not "practice what we preach.") 

    At any rate, incompetent management can almost certainly come to mind in many research and related organizations.  The people who most need to listen and learn, don't.  A famous example of someone trying to solve this problem may be found in the odyssey of W. Edwards Deming in the last century. He did not have much luck in the US.

    So what can be done to encourage more responsible leadership?  I think that good  leadership has most often occurred at levels below that of the ones with the most control, and that this is a further frustrating factor.  It is very difficult to have responsibility and no authority to perform it. How do we encourage better management and decision making?  How do we encourage a more cooperative and less antagonistic environment, when people often take control because they are egotistical by nature?

    Though this seems an obviously universal problem, circumstances and emphases vary.  Perhaps some anecdotes (no names, please), though hardly a scientific study, may stimulate some ideas for creative problem solving.

    - Thank you.   

    Ramon Quintana · University of California, Los Angeles

    One way to circumvent "bad decision" making at any level is to "automate" the decision making process. This is where good rule making comes in. You can engineer the process as they do in many technologies, through actual changes in the machinery. You can also instutiionalize the good decisions. We've done this in our own society through laws and even the constitution. 

  • Is energy minimization really needed for a typical MD simulation?

    Does energy minimization really needed for a typical MD simulation? I think the energy become minimum during for example NPT run. Am I ok?

    Roman Belousov · The Rockefeller University

    In statistical mechanics of equilibrium and non-equilibrium steady states the initial state  is irrelevant. Therefore, as most of the standard text books on MD suggest, you don't need even to worry about some "random" placement of atoms, you can arrange the configuration in a perfect arrangements of a cubic lattice, say, and the simulations will take care of it. The kinetic energies of initial state, though, are usually made consistent with the desired temperature, but even that is not always required, depending on the MD method in use. It is however recommended that the system is aged a bit, before you start actually doing any measurements. That is, just let it evolve for a short time, and then take the final state as the initial state of a new simulations, where the actual measurements are conducted.

  • Xinfu Gu added an answer in Bravais Lattice:
    In martensitic transformation in steel, why should we consider BCT by joining the face centered atoms of FCC even though FCC has higher symmetry?

    FCC has 3 fold symmetry but BCT doesn't. So why should we draw a BCT inside a FCC and name it as martensite. A reverse can also be done where we can draw BCT and they get a FCC out of it. If so in 14 bravais lattices there should be no BCT. How should we overcome this?

    Xinfu Gu · Tsinghua University

    Hi Bolmaro, I donot doubt about the statement (one have different way to plot different unit cell for the same structure), and just try to explain it. The drew *BCT* and FCC is the same lattice  but different way of draw unit cell like I show in the first figure. 

    BTW, for general BCT structure, one can not draw FCC structure from it, because BCT has lower symmetry. 

  • Adam Langlois added an answer in Anisotropy:
    What does the value of "r" signify in a steady state emission anisotropy measurement? What is the range for the "r" value?

    I am making some steady state emission anisotropy measurements.  To do this I am measuring the emission spectrum of my sample (at a single excitation wavelength under continuous excitation).  I make four measurements:

    1. Vertical excitation / Vertical emission             (I_VV)
    2. Vertical excitation / Horizontal emission         (I_VH)
    3. Horizontal excitation / Vertical emission         (I_HV)
    4. Horizontal excitation / Horizontal emission   (I_HH) 

    Once this is done I apply the equation:

    r = (I_VV  -  GxI_VH) / (I_VV  +  2GxI_VH)   

    where: G =  I_HV / I_HH   (correction for the emission gratings)

    This measurement is done at both 298K and at 77K in 2-methyltetrahydrofuran.  At 298K we observe almost no change in the anisotropy (a value close to zero is obtained for all wavelengths).  At 77 K (in a glassy matrix) we see a very different result (as expected as the molecule is immobilized in solution).

    The problem that I have is that I know do not know how to interpret these results.  Most books talk about excitation anisotropy an time-resolved anisotropy. I need to know what the r-value signifies for the measurements that I made.  Also what is the range of r-values for this type of measurement?

    I have attached a document to further show that we are seeing in our measurements.  Any help would be appreciated.  

    Adam Langlois · Université de Sherbrooke

    I took the advice given to me and made a measurement onf the anisotropy for Rhodamine 6G in Glycerol (as done in the EdInst. booklet.  The Booklet does not give the excitation wavelength so i just excited at 490nm as this seemed to be an appropriate wavelength.  

    I was able to re-produce the curve that is given in the booklet using my measurement method.  

    Note also that I made the measurement first in a 1cm cuvette (and reproduced the literature) I then made the same measurement in an NMR tube which i place in an EPR dewar (without liquid nitrogen) and again was able to reproduce the same anisotropy curve.

    From this we can conclude that the round nature of the NMR tube/dewar assembly does not lead to a significant depolarization of the light .

    Also the method that I am using seems to work.  

    We are now checking the alignment of the polarizers with a scattering solution.  

  • Van Van Than asked a question in Income:
    What is the function of the wave transmission coefficient on a sand-filled geotextile submerged breakwater?

    What is the function of the wave transmission coefficient (Kt, required reduction of incoming waves) on a sand-filled geotextile submerged breakwater?

  • Ousmane Sadio added an answer in NS2.:
    How do I Implement a dual stack gateway in NS2?

    I have a scenario in my master thesis that it is part of an smart city project including some mart home. every home have some sensor nodes in it to detect the different level of gases inside. homes are connected to each other via multi hop routing . so I need a dual stack gateway in every home to support both zigbee and wifi protocol and be able to connect to the home nodes with zigbee and connect to the other gateways with Wifi. I don't have any clue please guide me how to implement this dual stack gateway in NS?
    Regards,
    Behnaz

    Ousmane Sadio · Ecole Supérieure Polytechnique, Dakar

    You can also try to work in a real environment by using Arduino, Raspberry Pi... as Xbee Internet Gateway.  You can easily make changes to the proposed source codes.

  • Hailee Rogers asked a question in Western Blot:
    Has anyone tried to revive fixed tissue for western blot?

    I am specifically working with human brain tissue. Most of the tissue has been in formalin for 2-10 years. I have read a couple papers claiming to have revived their tissue with certain heating+buffers protocols. I have tried a few protocols and have gotten very poor protein quantities in my western blots.

    Any suggestions or information about formalin-fixed tissue would be very helpful!

  • Kathleen D Toohey added an answer in Roman History:
    Do you know anything about any paper or article written about Roman societas (partnership contract) ?

    I am conducting research about this topic (more accurately about actio pro socio) and i need some clues.

    Kathleen D Toohey · International Arthurian Society (North American Branch)

    Another good starting point might be J A Crook's book, Law and Life of Rome, which does have some detailed discussions on Societas and related legal topics.  (See Index.) 

  • Hailee Rogers added an answer in Housekeeping Gene:
    What is a suitable housekeeping gene for human brain tissue?

    I know beta-actin is pretty univerally used. As well as GAPDH. But for human brain tissue, is there a better housekeeping gene? I need this especially for neurodegenerative disorders and autism.

    Hailee Rogers · University of California, Davis

    Thanks! Those papers are very helpful.

  • C. Allen asked a question in Recording:
    Station locations and effective operation dates for those stations used to calculate the ISC-GEM records, particularly post 2009?

    Can someone please provide the list of station locations and effective operation dates for those stations used to calculate the ISC-GEM records, particularly post 2009?

  • Nancy Ahmed added an answer in Oral Gavage:
    What are the complications associated with oral gavage and cause death in mice?do they include stomach gas accumulation?

    I had 2 mice dead after oral gastric intubation, and after dissection I found huge gas accumulation in the stomach in both of them but also I found in one of them space filled with pus between muscle fibers of its left shoulder (which I don't know its cause also).

    Nancy Ahmed · Assiut University
    • Thank you Dr.Juliana , about fasting, I did not know about it at all besides how can I do this daily before gavage. How does this affect on the gavage success?

    I would be so grateful if you send me the texts and the sites you mentioned

  • 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 we 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 and inaction are 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 quick fix 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 quick fixes 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.

    Raveendra Nath Yasarapu · Technische Universität München

    Mike:

    IMHO, intellect is secondary. The Soul/Spirit is paramount. We/Science have/has barely scratched the surface.

    Regards

  • Kire Jakimoski asked a question in ns-3:
    Does anyone has experience with vertical handovers in ns-3 simulator?

    Heterogeneous mobile and wireless networks.

  • Amir Navidfar added an answer in Composite Material:
    what is the Structural advantage of carbon nano particle reinforced composite ?

    I want know which properties nano particle reinforcement enhances in composite .

    Amir Navidfar · Istanbul Technical University

    your question is unclear, but Carbon nano particle, especially carbon nanotubes can improve mechanical, electrical and other properties of polymer base nanocomposites.

  • Anyone knows a case of a social-ecological system illustrating the human capacity of learning and deliberate transformation to increase resilience?

    I am searching a paper on a case of a SES (social-ecological system) that illustrates the human capacity of social learning, enabling deliberate transformation of the SES, for example to a higher scale of governance, thereby possibly increasing resilience. I am looking for an example for any kind of deliberate transformation, e.g. in urban management, fisheries, forest management, protected areas, community building, etc; it doesn’t have to be a governance scale transformation, but ideally a system that undergoes the adaptive cycle phases and where a deliberate transformation led or might lead to increased resilience. Does anyone know of any such case? Thank you.

    Tobias Luthe · Hochschule für Technik und Wirtschaft in Chur

    Thank you so much David, Adriana, Pascal, John, Patricia, Yvette, Lea - I see there are so many more great examples out there and will further explore your recommended literature. I guess an idea for a new paper could arise from this, comparing empirical cases of SES resilience increments by governance transformation....

  • Is there any literature on equivalence?

    Specifically I will be examining the impact of event sponsorship on brand image looking at 1 music event and 1 sporting event. Ideally I need to choose events that are equivalent in terms of attendee profile, image etc. As such I would like literature that speaks to equivalence and how objects are treated when there isn't equivalence.

    Tricia-Anne Morris · The University of the West Indies at Mona

    Hi Christophe thanks so much for responding. I have reviewed some of the congruence literature but am yet to come across anything that deals with equivalence. Is there a particular author or paper you can suggest? Thanks again

  • Jose Ramiro Bertieri Quintero asked a question in KPO:
    Outsource of R&D services?

    I am working in a research proposal to identify the key factors to outsource R&D services, the objective is build a framework for an regional strategy of KPO sector (knowledge process outsourcing) , can you referr or share experiences or documents about this, thanks a lot

  • Julian Hill asked a question in Stasi:
    What is currently known about winter stasis in goats?

    Winter stasis is a complex multi-factorial syndrome observed in goats where weight gain falls rapidly during the winter - we currently do not understand the drivers that result in this phenomenom 

  • Wayne Wood asked a question in Frameworks:
    Are there any theories or frameworks about creating and evaluating frameworks?

    I am doing a research paper on the creation of a new framework for a specialist discipline.

  • Dean Whitehead added an answer in Papers:
    Should scientific meetings give scientists 5' or longer for presenting papers?

    At the currently ongoing  EFORT meeting scientists are allowed only 5 minutes for presenting their research findings. This used to be longer. In my opinion 5min is way too short. What is your opinion?

    Dean Whitehead · Flinders University

    Agreed - 5 minutes might be fine for presenting summary of say 'pilot' studies - but to present findings from full studies is unrealistic an probably not that meaningful. The idea of presenting research findings is to 'celebrate' them in terms of their complexity, findings and impact. That can't be done in 5-minutes. You might as well present your studies as just bullet-list points. To add to it - what about Q & A's to follow?

    On the other hand, 20 minutes (with 10 minutes Q & A) used to be a 'standard' - and that can be too long. Somewhere in between 5 and 20 minutes is preferable.

  • During the transcription process of qualitative interviews, how do I deal with the multiple language responses obtained during the interviews?

    For an instance, during the interviews, if any response (or a fraction of it) is received in a language other than English. How do we enter such portions in the transcripts.

    If we need to Translate such portions to English, please elaborate on the aspects to be taken care of.

    Thanks in advance

    Zeljko Stojanov · University of Novi Sad

    I agree with Noman Mohammad about ensuring trustworthiness through member check. Comments from the people that are the source of your data is the key factor for ensuring semantic equivalence of original and translated text and validity of your findings.

    You can also read the following article:

    Fenna van Nes, Tineke Abma, Hans Jonsson and Dorly Deeg.Language differences in qualitative research: is meaning lost in translation? European Journal of Ageing, December 2010, Volume 7, Issue 4, pp 313-316. doi: 10.1007/s10433-010-0168-y.

    Regards,

    Zeljko

  • Sheridan Clare Mayo added an answer in Crystallins:
    How can I determine the index of diffraction lines for a novel organic crystalline semiconductor?

    I want to determine the hkl, for each XRD diffraction peak together with the interplaner spacing for powder of a novel organic crystalline semiconductor.

    Sheridan Clare Mayo · The Commonwealth Scientific and Industrial Research Organisation

    If the materials are crystalline within the layers, the combined structure will have a powder pattern which is something like a sum of the individual powder patterns. However which such a thin sample it will be very weak. Also with such thin layers you will likely get strong preferred orientation effects and peak broadening due to the small thickness. You could use indexing software to try and index the peaks of the individual patterns for the separate materials and use the results to try and identify peaks in the pattern from the combined layered material.

    What are you hoping to learn from the powder diffraction analysis?