Q&A

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  • What is the relationship between transformational leadership and innovation?

    I want to know if it is relevant to study the impact of transformational leadership on innovation by introducing organizational learning as mediator variable.

    Mahmoud Zouaoui · University of Manouba, Tunis, Tunisia

    Hi Caterina,
    Organizational learning is conceived in the sense of Organizational learning capabilities (OLC), defined as "the organizational and managerial characteristics or factors that facilitate the organizational learning process or allow an organization to learn".

    Factors as experimentation, risk taking, interaction with the external environment, dialogue and participative decision making.
    (Dibella et al., 1996; Goh and Richards, 1997; Hult and Ferrell, 1997; Yeung et al.,1999).

  • Israa Albarazanchi added an answer in Omnet++:
    I would like download JDK 1.6, can I get help?

    I would like download JDK 1.6 for OMNET++. How can I install JDK 1.6 under OMNET++? Can get help?

    Israa Albarazanchi · VIT University

    wt about this site ?

    http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

    wt i chose ?

    Windows x64 54 MB jdk-8u45-windows-x64-demos.zip 

    please need help

  • Bojana Coso added an answer in Affect:
    Is there any evidence of the lower BOLD signal for depression compared to normal people?

    Is there any evidence of the lower BOLD signal (or the whole brain signal) for depression compared to normal people?

    or is there any evidence of the lower brain signal for negative affect compared to positive affect? 

  • András Bozsik added an answer in Heritage:
    Can a Society really be Established and Sustained on Ignorance?

    The threatened, and in sadly too many cases destruction of world heritage sites by religious fundamentalists robs not only our generation of knowledge and culture but those to come.  

    This is not a new phenomenon, iconoclasm ironically predates the latest outbreak many centuries before Islam, so this cannot be a manifestation of Islam in any form. 

    Can a society or civilisation be established and sustained on ignorance and dogma or is it doomed to fail?

    András Bozsik · University of Debrecen

    Dear H. Chris,

    Dear All,

    Dictators or statesmen should not know physics, biology, mathematics, and not even mathematical modelling. I do not think that capitalist politicians were better educated in science than the communists. Lenin spoke several languages and was finely educated philosophically. Trotsky spoke also 2 or 3 languages and was an excellent chess player.  Dictators and leading politicians are mainly sly, ruthless and cruel. They know very well how to manipulate people and this is plentifully sufficient. This kind of people can easily find well educated people who are willing – for some money - to work for them.

    I think there is only one thing what politicians should know: to be able to distinguish good and bad. I think they were and are able to see the difference. This means, they are not ignorant, simply egoistic and without ethics.     

  • Dear Colleagues could any one tell me the difference between ferroelectric and Electret ?

    Dear Colleagues could any one tell me the difference between ferroelectric and Electret ?

    Doris del Carmen Rivero Ramírez · Instituto Superior de Tecnologías y Ciencias Aplicadas

    Ferroelectric materials have hysteresis. They are characterized with hysteresis loop and the remnant polarization. I suggest you read more about these materials on:
    1. Xu, Y. "Ferroelectric Materials and Their Application". Amsterdam: North-Holland, (1991).
    2. Bernard Jaffe, William R. Cook and Hans Jaffe. "Piezoelectric ceramics". Academic Press London and New York, (1971).

  • Somayeh Izadi asked a question in Iran:
    Can we use c-band data for estimation of above ground biomass in woodlands?

    We know l & p bands data are better than c-band data for estimation of AGB, But l & p bands data not available for woodlands in Iran.

  • Why are underground structures less susceptible to seismic damage during earthquakes?

    Through my research I noticed this observation in a lot of papers

    Alexandre Ribó · Ministerio de Salud, El Salvador

    Moreover,if the structure is located in the seismic bedrock it does not be subjected to the seismic site effects amplifications related with soil layers.

    You can read more about differences between seismic bedrock and engineering bedrock here:

    http://iisee.kenken.go.jp/net/yokoi/bedrock/

    http://seismo.geology.upatras.gr/MICROZON-THEORY1.htm

  • Can ethics be measured objectively?
    Ethics, ethical committee, ethical approval and other ethical related words are extensively used on Researchgate and other places. How to define and measure ethics in objective bases?

    Tomy

    There also exists  a CIF clause and that is "Carriage,Insurance,Freight" more expensive but sure..

  • What is an effective corn Nitrogen availability test?

    What do you think is the best measure of N availability to corn in a humid temperate climate?

    Susantha Jayasundara · University of Guelph

    Hi Jessica,

    I am assuming that you want to know an ‘effective soil N availability test for corn’ that can be used to decide how much N fertilizer need to be applied.

    If that is correct, the most widely recommended soil N availability test for corn in humid temperate climate is: Pre Side-dress Nitrogen Test (PSNT).

    That means: taking representative soil samples from top 30 cm soil depth at about 4-6 leaf stage of corn and determining the Nitrate-N (NO3-N) concentration in these soil samples.  Once we know the NO3-N concentration in the soil at a particular site, we can use a reference guide such as the Table 1-24 found in the link here:

    http://www.omafra.gov.on.ca/english/crops/pub811/1fertility.htm#nitrate

    Different regions in the US Midwest and in Canada use different reference guides to interpret this test for making N fertilizer recommendations for corn.  A brief comparison on how the PSNT is used in different States in the US can be found in the following link:

    http://www.spectrumanalytic.com/support/library/rf/Presidedress_Nitrate_Nitrogen_Test_University_Summary.htm

    I hope this information would be helpful.

    -SJ

  • Can anyone suggest article regarding the remedy for groundwater contamination by engine oil?

    I need some information about groundwater pollution by engine oil and find the inexpensive ways to treat them.

    Carly Hyatt Hansen · University of Utah

    These papers offer comparisons of a few approaches for remediation of oil-contaminated groundwater, and touch on costs. Are you only interested in economic cost, or environmental costs as well?

    Bioremediation of Petroleum oil Contaminated Soil and Water
    Jain, P K; Gupta, V K; Gaur, R K; Lowry, M; Jaroli, D P; et al. Research Journal of Environmental Toxicology5.1 (Jan/Feb 2011): 1-26.

    Comparison of biostimulation and bioaugmentation for remediation of soil contaminated with spent motor oil
    S. Abdulsalam M.Sc, PhD, I. M. Bugaje M. Eng., PhD, S. S. Adefila M.Sc, PhD, S. Ibrahim M.Sc, PhD

  • Where can I find District wise data of irrigation infrastructure developed in Maharashtra especially after green revolution (Ancillary data) ?

    I want to find Irrigation potential developed in Maharashtra for every district specially after 1950's till date along with area under various crops varieties?

    Where can I find such data?

  • Amit Dharia added an answer in Creep:
    The creep of materials and what does it mean?

    The creep of materials and what does it mean?

    Amit Dharia · Transmit Technology Group, LLC

    Creep is slow deformation under constant stress.  Think of power cables or water carrying pipes or even metal screw fastener in plastics..  They are under constant stress.  When you apply constant stress, until entanglements uncoil, there will be no effect but once that is done, material will "give in".  Creep is very important property for durable items.  The way we determine is by hanging dead weights on molded or extruded samples and follow % elongation as function of time.  Anything which will reduce molecular mobility, i.e. increase molecular weight, attraction between molecules, increase Tg, adding reinforcement, increase hydrogen bonding will increase creep resistance.  While adding anything that increase free volume like plasticizers, degradants, elastomeric softeners will reduce creep resistance. 

  • What are the lake water quality pollution control measures?

    Lakes are getting polluted, if same condition getting prolonging entire world in danger.

    Cynthuja Partheeban · North Carolina State University

    Lake pollution is generally caused by various sources. Export of nutrients through drainage water from agricultural lands is one of the major ways to create eutrophic condition which is the major driver for hypoxic zone. To reduce the nutrient export in the lakes, drained water can be treated for nutrients by various management practices such as denitrifying woodchip bioreactors, constructed wetlands, and controlled drainage.

  • Enrique Valderrama added an answer in Sputtering:
    Why is 13.56MHz used in RF sputtering?
    How is this frequency achieved?
    Enrique Valderrama · Oral Roberts University

    agree I love that book. :)

  • Does anyone recommend decent books, articles on radical Third World movements that use violence to achieve regime change and redraw colonial borders?

    I need this to support the following proposition I make:

    While shedding considerable light on the myriad of ideational, political and socioeconomic forces that fed the rise of ISIS, Arab scholarship on ISIS’s origins remains highly impressionistic and not firmly anchored in social sciences theories about the rise of radical movements that deploy violence not only for the purposes of regime change but also to redraw colonial borders.

    Ibtissam Ahmad Klait · Lebanese American University

    Here is another book attached! pls check it!

  • Why does dilution of homoeopathic medicines enhance their potency? Is this not against scientific phenomena?
    I have been told by homoeopathic practitioners that dilution and potency of homoeopathic medicines is inversely proportional. This means the higher the dilution the more potent the medicine will be and vice versa. I have doubts which may be due to my bias because personally I did not find any experience of homoeopathic medicine effective.
    Steingrimur Stefansson · HeMemics Biotechnologies Inc.

    Hi Prem, so you agree with  Kent? 

    Bacteria have nothing to do with disease?

    Germ theory of diseases is bogus?

  • Brian David Fisher added an answer in Data Analysis:
    What is Visual Analytics ?
    Visual Analytics tools which are used to analyze economic data
    Brian David Fisher · Simon Fraser University

    Certainly there are many who use  visual analytics for marketing buzz, but it is actually  a defined term. It is "the science of analytical reasoning facilitated by interactive visual interfaces" "illuminating the path: an R&D agenda in visual analytics" (electronic version at  http://vis.pnnl.gov/pdf/RD_Agenda_VisualAnalytics.pdf ) that is the subject of Visual Analytics Science and Technology (VAST) a large IEEE conference. 

  • Matthew Hoy added an answer in Pastoralism:
    I am looking for academic papers on the redactional and soci-historical questions on the narrative of the healing of the Leper?

    I am looking for academic papers on the redactional, socio-historical, cultural, literary, theological and pastoral questions regarding the narrative of the Healing of the Leper.

    I need to find sources as soon as possible to make amendments to my Masters thesis as my supervisor has requested i find additional theory on the above.

    Matthew Hoy · University of Johannesburg

    Thank you both SO much, Michal your articles are amazing and David, to answer your question I have.

    God Bless you both!

  • Mario Valentino added an answer in Brain Imaging:
    Why would my cleared tissue sections become more opaque upon mounting them on slides?
    I am clearing (with glycerol) thick (~160um) mouse brain tissue sections. They appear nearly transparent in the vial upon clearing but once they are mounted on Superfrost plus slides, they are no longer transparent. Any suggestions?
  • Yue Lu added an answer in Alexa Fluor:
    Does vector mouse to mouse IgG blocking reagent works with invitrogen Alexa fluor conjugated secondary antibodies?

    Hi, I'm recently working on immunostaining for Pax7 in mouse muscle cryosections. The primary antibody is mouse IgG1 anti-Pax7 (DSHB) and it seems the only antibody working in mouse with a Mouse to Mouse (MOM) IgG blocking reagent. I tried the Vector MOM IgG blocking buffer followed by blocking with 15% goat serum, anti-Pax7 overnight and Invitrogen goat-anti-mouse IgG1 for 30min. It turned out that there was very intense non-specific background. I got this protocol from a Nature paper and also tried different dilution of primary and secondary antibodies but all didn't work. Does anyone have experience with the mouse to mouse kit?

    Yue Lu · Virginia Tech

    Thanks Bryon!  Actually I only used the mouse Ig blocking reagent rather than all the components in the MOM kit in my protocol. Maybe that's the reason. In addtion ,did your lab used glycine to quench the aldehyde in sections after the fixation?

  • I have a chromatogram of my sample and I have standards. Now what?

    Hello everybody!

    I am initiating my research on HPLC. I have used a C18 Accucore column, A gradient program of 40 min (60min in total) using as eluents MeOH (A) and Water(B), both acidified with formic acid 0,1%.

    My samples have 0,5mg/ml of concentration. My standards(11) concentration are 1mg/ml...of course the peaks i see in my samples are quite smaller. I injected a sample with the mixture of all standards in order to identify them in the run.

    Ladies and gentlements...what is now the best procedure to analyse and identify (if possible) some of the peaks?!

    All were injected in 3x, but it seems to me that are some deviations of peaks in some situations....not very happy with this?

    Can anybody suggest me a way of solving my problem? Also, is there a free software to treat chromatograms (actual software is chromeQuest) and possible do statistical treatment?

    Thank you very much

    Joana P. A. Ferreira · University of Lisbon

    Hello!

    Abdur and Vítor, I am using a UV-DAD analyser, so i will just have the option of comparing the RT and UV profile!

    I thought there would be available a software for analysis of chromatograms FREE...anyone knows one?

  • Shrinidh Joshi asked a question in Nitrite Reductases:
    Can anybody suggest how to measure Nitrite reductase activity in Cells?

    I am using Human MNCs and want to measure the Nitrite Reductase activity present in the cell. I am certain about the release of NO, by means of DAF-FM sensitive signals produces by cells (I have used Flow cytometry to measure the signal). I want to confirm the origin of NO. From previous experiments, I doubt that source of NO is not NOS enzyme but it may be Nitrite reductase and I want to confirm this. 

  • Should one consider the C-C Lennard jones interaction for a single layer graphene?

    Should one consider the C-C Lennard jones interaction for a single layer graphene?

    Zacharias G. Fthenakis · Foundation for Research and Technology - Hellas

    This is rather a technical question. A way to do it, is not to consider any VdW interactions between neighbouring atoms, lets say, up to 4th nearest neighbours in the chain. Thus, VdW interactions would occur only for 5th or higher nearest neighbours of a certain atom of the polymer chain. You may also use a cut off distance as the range of VdW forces, thus avoiding interactions if the interatomic distance is higher than that cut off distance.

  • Amit Dharia added an answer in Formic Acid:
    Does anyone know about polyamide 66 (Nylon66) Hansen solubility parameters (HSP)?

    There are different values reported in the literature!

    The strange thing is that formic acid is an excellent solvent for PA66, but all the reported HSPs are far different from those for formic acid. The R-value (gyration radius, dissolution distance) for formic acid with respect to reported PA66 HSPs is even greater than two, but it dissolves PA66 readily! While, regarding HSPs, it should not dissolve!

    Any explanation/suggestion?

    Amit Dharia · Transmit Technology Group, LLC

    Solubility Parameter for Nylon 66 is 13.6 (cal/sec**1/2)and formic acid has it 13.5. So it will dissolve.  However, Nylon has very strong hydrogen bonds and Solubility parameter will not make much sense. 

  • Umut Eser added an answer in Online Learning:
    Has anyone used Prediction Suffix Tree (PST) before?
    What is the advantage of using PST in online learning if the speed is not important?
    Umut Eser · Harvard Medical School

    Just off the top of my head:

    1. Memory efficiency

    2. parameter estimation, esp. for the sequences not contained in the training list. 

  • Karina Tonon added an answer in LC-MS:
    How can I separate two isomers oligosaccharides using LC-MS?

    Hi, I'm developing an LC-MS method for the quantification of 15 human milk oligosaccharides but I'm having trouble separating two isomers (LNT, lacto-N-tetraose and LNnT, lacto-N-neotetraose). I want a good resolution between them, affecting as little as possible the other oligosaccharides.

    I'm using as mobile phase water and acetonitrile, both with 0.1% formic acid and a Hypercarb column (100x2.1mm, 3u, Thermo Scientific). The LC gradient is 0-12%B in 21 min; 12-40%B in 32 min; 40-100%B in 37 min; 100%B in 42 min; 0%B in 43 min, keeping at 0%B up to 55 min. I've tried several changes in the chromatography, but the best I got is in the image attached.

    Does anyone have an ideia what I could try?

    Karina Tonon · Universidade Federal de São Paulo

    Hello, thanks for the help!

    Rosana, I tried to soften the gradient in several ways. I've used 1.5; 1.0 and 0.5%B/min and what I got were two peaks even more united... I don't understand why.

    Ken, in the attached chromatogram I did exactly what you suggested, kept the isocratic gradient of 12%B for a few minutes, but I didn't get a complete resolution. However, it was the best result I obtained so far.

    Miloudi, honestly I don't understand about chiral membranes. I don't know if it applies in human milk oligosaccharide analysis, because I didn't find any reference in the literature.

    After much effort in optimizing the method, I got a great sensitivity and resolution of other 5 groups of isomers. The only problem is the separation of LNT and LNnT, which I expected to manage with little change in the gradient, but nothing seems to work ...

  • Björn Drobot added an answer in Fluorescence:
    How can I correct the fluorescence measurements due to inner filter effect in protein-ligand systems?

    Some works correct with a factor which take into account the absorption data of the ligand and others works use the absorption data of the protein-ligand complexes. Which would be the correct form? We are performing measurements with constant protein concentration, i.e. vary the ligand concentration.  

    Björn Drobot · Helmholtz-Zentrum Dresden-Rossendorf

    If it is possile to work in diluted solutions it is often not important to consider the inner filter effect. In most cases fluorescence signals are orders of magnitudes higher than absorbance.

  • Can anyone identify the object that was found in the lower Jurassic sediments and whose size is 5-10 μ ?

    The object (more objects) was found in the examination of of calcareous nannofossils in the Lower - Middle Jurassic sediments. It can be a part of the nannoplankton body. Thank you for your help :-)

    Angela Baldanza · Università degli Studi di Perugia

    Dear Silvia,probably is a fragment of small size Nannoconus, the first specimens occurred in the middle-upper Jurassic, Nannoconus minutus (?)

    Best wishes, Angela

  • Is there an existing research on how a person's digital persona affects his ability to obtain credit?

    I am interested in hearing from those who may have insights into credit-scoring systems or other methods for evaluating creditworthiness based on social media and other online content of the individual.

    Andrea Lee Negroni · American University Washington D.C.

    Thank you, I have read several things about Lenddo. Some of the small business lenders are acknowledging using social media references, but I haven't got any confirmation from consumer/home mortgage lenders.