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  • Does someone knows articles about the application of economics model in software maintenance?

    I am doing a literature review in this topic and collecting nice papers as the seed pool. Thank you.

    Wishnu Prasetya · Universiteit Utrecht

    Well, not really in maintenance, but maybe this gives some information:

    "What is your software worth?"

  • Bruno Lopes added an answer in Microbial Taxonomy:
    How can I classify bacteria to species level?

    I have 16S gene sequences and some of them are quite different. When I create a tree using mega I can see that they are closely related but not very close? Whats the criteria for classifying bacteria to species level?

    Thanks in advance.

    Bruno Lopes · University of Aberdeen

     Thanks everyone for all your replies

  • Laurent Reynaud added an answer in Raspberry Pi:
    How can one configure Raspberry Pi with Camera and output on computer?

    Hi All. I want to work on Raspberry Pi interfacing with camera. I need to see the output on computer. As a novice in Raspberry Pi, I need to get guided. Any help would be highly appreciated.

    Laurent Reynaud · France Telecom - Orange Labs

    Hi, by computer I assume remote computer.  There are several methods to stream the raspivid output to a remote computer, including the following approaches: the use of VLC (cvlc) over RTP/RTSP, the use of GStreamer pipelines (gst-launch), or even send a raw H.264 flow over netcat to you remote computer. May I suggest the following resource which documents (in the general lines) those methods: https://youtu.be/sYGdge3T30o


  • Randy Kummer asked a question in Flame Retardants:
    Flame Retardant Mechanisms?

    Looking for information regarding Thermoset and Thermoplastic Flame retardant Material mechanism Particularly containing Montmorillonit materials?

  • Georgios Antonoglou added an answer in Vitamin D:
    What is the meaning of 1,25(OH)D/25(OH)D (serum concentrations)?
    Is there rationale behind studying the ratio of serum 1,25(OH)D/25(OH)D if one can control for the seasonal variation of 25(OH)D?
    Georgios Antonoglou · University of Oulu

    Hi Jean!

    Thanks a lot for your comment on this thread. Can I ask what is the method and kit you are refering to? Indeed, it does not sound promising if one third of what you detect is actually not 1,25(OH)D.



  • Which is the best test to determine the minimum dimensions to keep after a Principal Component Analysis?

    In particular when there is no clear "elbow" in the scree plot and when to explain 70% of the variance in the data you need to keep more than 8 principal components.

    Francisco Prieto-Castrillo · New England Complex Systems Institute

    Thanks for the tips! They are all very helpful. My variances against the PCs drop like: 21.7715 9.6007 3.9219 3.2721 2.4053 2.0386 1.4773 1.2586 1.2080 0.9716 0.9252 0.8587 0.8162...resembling a power law. There is a sort of sharp drop from PC2 to PC3 but the fall is smooth. I was looking for some criteria implementable in R.  

  • Barry Turner added an answer in DOM:
    Does anybody have previous experience of obtaining full court transcripts of trials (preferably Rape) for the purpose of PhD research exploration?

    I'm currently designing a mock trial simulation and require a trial transcript to ensure it is as realistic as possible. The ritual of how judges address juries and other court personnel in rape trials (or any trials for that matter) is what I'm hoping to get access to - please help if you can

    Dom Willmott

    Barry Turner · University of Lincoln

    Obtaining full court transcripts is very expensive.  There are better ways to ensure that your mock trial is realistic.  I teach on court procedure, criminal evidence and especially on the special circumstances surrounding sexual offence trials.  

    The trial transcript would not give you the full picture but a practising criminal lawyer could.  I have been out of practice for a few years now but the ritual has not changed since Crown Courts were introduced in the 70's.  I can give you a blow by blow account of a rape trial if you like but it would take a while and would be easier if we could meet. 

  • Arshad Khan added an answer in Quantum:
    What is fluorescent quantum yield and how do you calculate it?

    What is fluorescent quantum yield and how do you calculate it? Are there many procedures and if there are which one is more accurate?

    Arshad Khan · Southeast University (China)

    Thanks Mr.Avinash Mithilesh Singh

  • Behrouz Ahmadi-Nedushan added an answer in Men:
    When you hear the words "black and white" what ideas that run in your mind?

    "black and white" are two opposite words include for example the white men and black men it indicates the color of the skin, "black and white" also indicates the good and evil, love and hate, peace and war ........

  • Yahia Hadj Seba added an answer in Sputtering:
    How does the base pressure influence the Sputtering deposition?

    I want to deposit metallic Silver for contact by sputtering method. will the properties change if the base pressure is not good

    Normal my sputtering system maximum pressure it goes is around 2.2 X 10-5 mbar after admitting argon during deposition I am maintaining the pressure of 3.2 X 10-3 mbar

    Base Vacuum should me more than  10-7 - 10-8 mbar for metal deposition. But normally we are depositing the materials at low pressure by sputtering method

    How the base pressure will affect the metal film properties

    Yahia Hadj Seba · University of Science and Technology Houari Boumediene

    Base presure in ordre of 10^-5 in good you cane reduce the base pressure by  introducing a heater system in you chamber. This heater system should be placed in the substate holder. This heating system enables  chamber degassing.

    To degas the substrate holder and the substrates in an effective manner it is necessary that the heating temperature is greater than that of deposition .

    This degassing operation is performed in order to reduce or eliminate the impurities , particularly oxygen.

  • Is It possible to design a motor with high torque and low speed?

    In  my practical application requirement i want higher torque and at lower speed motor is  it possible to design a normal PERMANENT MAGNET DC MOTOR to a high torque dc motor with change some modifications in winding and permanent magnets ?   

  • Sarit Charuchaibovorn asked a question in Primer:
    How to check the large dna sequence (in expression vector) ?


    I want to check gene sequence that is a large size (3.7kb). This gene is located in MCS of pQE9 vector (Qiagen). 

    How many primers that i should design for check full gene ?
    Do i need to sequence double strand (using both forward primer and reverse primer)

    Thank you for your suggestion

  • Have primate species other than Homo sapiens engaged in acts of aesthetic creation?

    For several years some scholars have accepted the engraved pieces of ochre from Blombos cave in South Africa, at least one of which has a geometric cross-hatched pattern, as evidence of early modern human aesthetic creation (ca. 75,000 BC). See: Henshilwood, Christopher S.; d’Errico, Francesco; et al., “Emergence of modern human behavior: Middle Stone Age engravings from South Africa,” in Science, new series, vol. 295, no. 5558, February 15, 2002, pp. 1278-1280 (http://www.sciencemag.org/content/295/5558/1278.abstract?sid=da7c3755-b2bc-4ced-93da-2c024c50b1fd, access: March 14, 2015).

    The recent discovery of similar engravings on shells on Java, from ca. 500,000 BC -that is, long before the emergence of modern Homo sapiens-, suggests that aesthetic creation evolved gradually. See: Joordans, Josephine C. A.; d’Errico, Francesco; et al., “Homo erectus at Trinil on Java used shells for tool production and engraving,” in Nature, December 3, 2014 (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature13962.html, access: March 14, 2015).

    Suggestions that chimpanzees make aesthetic decisions while painting are intriguing. See the following texts and video:





    Can anybody point me toward additional studies on aesthetic creation by nonhuman primates, either in the archaeological record or among our contemporary primate cousins?

    David Charles Wright-Carr · Universidad de Guanajuato


    A good example of significant asymmetry within a roughly symmetrical structure is the human (and non-human primate) brain, with its hemispheric lateralization; this has profound implications for understanding aesthetic creation.

    Thanks for the "science" quotes from Close. It's sad that most people, indeed many within the academic community, don't see the radical nature of this perspective and its potential for transforming our understanding of things across traditional disciplinary boundaries.

  • Bushra Javed asked a question in Java:
    Anyone has used DB Toolkit to remove duplicate sequences?

    I am using Java coding to mark and remove duplicate sequences, it's working perfectly fine for me but supervisor asked me to use DB toolkit. I have two duplicate sequences in my file, but DB toolkit is not showing any error. Is DB toolkit is reliable?

  • Ayyaz Ahmed Bhatti asked a question in Semen:
    What is the best method for semen collection in rats?

    There are some methods like rectal stimulation and electric stimulation for semen collection... i have to take samples more than once from rat... so any suggestion of a method with minimum hazard to rats

  • Vasim Akram asked a question in Power System Dynamics:
    Do any one have "Y. N. Yu, Electric power system dynamics. New York: Academic Press, 1983."?

    Electric Power System Dynamics

  • Fatma Özkan asked a question in Listening:
    Is there any difference between to hear and to listen from the perception verbs in term of semantics?

    Is there any difference between to hear and to listen from the perception verbs in term of semantics?

  • Erica Kistner added an answer in Biological Control:
    What are your thoughts on using Biological control as a countermeasure against invasive alien plants?

    The "enemy release hypothesis" is an often documented mechanism by which alien plants become invasive. There are opinions of using native enemies (may be modified) against these weeds in invaded ranges? Are there examples where such control strategies have worked? And is there any future for the approach

    Erica Kistner · University of California, Riverside

    Good points everyone. Applied biological control is an important component in Integrated Pest Management programs. Hoddle 2004 provides a great overview on this topic. Biological control has changed dramatically over the last 100 years. In the US, exotic biocontrol agents have to undergo extensive safety testing and get federal apporval  before they are released in the field. They are often specialists that only attack the target pest.

  • Sulasy Rohmy asked a question in Water Quality:
    Does anyone have information about Puntius denisonii breeding ?

    1. What is the  suitable technic for breeding them?

    2. What are the conditions? (environment and water quality)

  • What concentration of tamapin/apamin is suitable for behavior test?

    Hi all,

    Do you guys have any idea to use the tamapin/apamin in behavior experiments? I want to use this drug to block the SK2 channel and see the effect in learning behavior. I am not sure which concentration and how should I administrate this drug in the primary motor cortex of mouse. Does any one have done before?



    MOHAMMAD SHAHID · George Washington University

    Thank you guys for your comments. I got some good publication though these links. Hope these will be very helpful for me.

  • Mehdi Hedayati added an answer in Foam Cells:
    How can I oxidize LDL for effective in vitro foam cell formation in THP1 cells?

    Can anyone help me with a standardized protocol on oxidation of LDL? We have fetched LDL from Sigma-Aldrich. There are varied protocols related to it which has left me confused. If anyone could help.

    Mehdi Hedayati · Research Institute for Endocrine Sciences

    Dear Anandita,

    Usually, oxidizing metal ions (e.g. Fe or Cu) use for in Vitro oxidizing LDL. Briefly:

    LDL (100 pg protein/ml) incubates with either 6 pM FeSO4 or 10 pM CuSO4 in tissue culture wells for up to 24 h at 37°C in triplicate at the indicated pH value. This gives a final concentration of EDTA of 5 microM and a net concentration of CuSO4 of 5 microM taking into account the EDTA concentration. EDTA-copper complexes are inactive as regards LDL oxidation in simple phosphate buffers but Low concentrations of EDTA do not inactivate FeSO4 in
     simple phosphate buffers. For details please see attached file.




  • Arnold Trehub 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.

    Arnold Trehub · University of Massachusetts Amherst

    Ravinder: "You are correct  that we are dealing with a 3 D volumetric space. [1] However that at neuronal level cannot sense, think and act without an central anatomical coordinator .I believe that Thalamus deserves that status . Allowing that status to thalamus sets the stage for solving the puzzle . [2]"

    1. There is no question that the thalamus is the principal brain structure/hub for receiving exteroceptive and interoceptive sensory patterns and projecting them to all cortical modalities in thalamo-cortical feed-forward feed-back loops. There is also no question that the thalamus serves as an important sensory gating and modulating mechanism. But I don't know of any evidence that the thalamus represents 3D space from the fixed locus of perspectival origin that is required for subjectivity.

    2. If you look at Fig. 16.1 in "Overview and Reflections" on my RG page, you will see a depiction of some the mechanisms that are needed to "sense, think and act". I don't think that there is evidence that the thalamus has all of these mechanisms.

  • Sok Heng Lay asked a question in Time:
    Time Trends Vs Time Dummies?

    Can I include both time trends and time dummies when running panel data? What is the difference between them? I think that my data may have problem of unit root.

  • Seth Agbo added an answer in Professional Identity:
    How do pre-service teachers develop a sense of professional identity?

    Teachers and Researchers are said to have distinctive discourses and artefacts although there is teaching involved. Student teachers are "caught" in both domains at the point of practicum. It is a contested site that requires further investigation especially in ESL context where they are also learners of English.

    Seth Agbo · Lakehead University Orillia Campus

    Kaarthlyalny, you’re very right about how the politics of education may stifle teacher development. Research indicates that teachers that mindlessly follow ministry and school board policies are usually not effective teachers. A BBC news article, “What Makes a Good Teacher" states clearly that effective teachers are those that practice what is known as “creative subversion”, that is, effective teachers are those who do not slavishly follow policies but creatively adjust them to meet the needs of their students. Similarly, in his book, “I Won’t Learn From You”: And Other Thoughts on Creative Maladjustment, Herbert Kohl speaks of “creative maladjustment” as “subversion of the system that most good teachers do” (p. 128) and goes on to define creative maladjustment as “examining the nature of the life you are expected to lead as a teacher and sorting out what is sensible and beneficial to your students from procedures meant simply to keep things under control” (p. 131). It is part of the concept of reflexive subjectivity for teacher candidates to reflect on what makes sense and what doesn’t in dealing with one’s students and adjusting accordingly to meet their needs. In that case, my students explore issues as how to deal with the politics of education. It is true that creative subversion and/or creative maladjustment can land beginning teachers in trouble, but there are ways to get around it, which is the subject of another discussion. For convenience, I provide the link to the BBC article below and a full reference to Herbert Kohl’s book.


    Kohl, Herbert (1994). “I Won’t Learn From You”: And Other Thoughts on Creative Maladjustment. New York: The New Press.

  • Is kalman filter an adaptive filter?

    mathematics of the filter says it has two parts ,first one is estimating and second one is predicting. I am having doubt in prediction part. How it predicts the next step?

  • Abhijit Mitra added an answer in Insects:
    What is the easy research methodology to study on species replacement?

    I would like to work on species replacement of indigenous insects in an area where invasive species of insects have become more abundant but population of indigenous insects have become very less infesting in a commodity. What is the easy research methodology to study on species replacement?

    Abhijit Mitra · University of Calcutta

    You can see this in google

  • Ramon Quintana added an answer in Probability:
    What is the relationship between randomness and probability?

    Are randomness and probability independent of one another, or does one depend on the other, or are they different expressions of the same thing?   

    Ramon Quintana · University of California, Los Angeles

    All: (My two cents)

    We cannot resolve philosophical questions about randomness from purely abstract notions in mathematics or computing. We must look at the world and see how it operates. Is the world fundamentally deterministic or intrinsically random? We usually think of determinism and chance as two opposite and incompatible states. For instance, deterministic algorithms cannot produce true intrinsic randomness. And likewise, intrinsic randomness alone should not produce algorithmic order. If these two are incompatible can they nevertheless work together? Intuitively, it seems paradoxical that determinism and chance could operate together. You would think that one defeats or “dilutes” the other. However, it is possible that algorithmic programs in Nature could be “goosed” by the intrinsic randomness of quantum physics. This would avoid the twofold paradox of obtaining intrinsic randomness from deterministic processes, or algorithmic order from absolute randomness.

    To tease apart the paradox, consider a pair of metaphorical "quantum coins". The quantum coins adhere to all the Bell Theorem requirements. This includes choosing the position of either coin at random. That is, “the measurement choice must be random.” The quantum coins also exhibit individual indeterminism. We can toss either coin separately and get heads 50% of the time. However, the quantum coins have a sort of deterministic correlation. If entangled, when “measured or observed” they will always exhibit the opposite side. As such, they appear deterministically linked. Is this a mix of chance and determinism in one system of coins? Is this the case of an “event influenced by another event” while remaining intrinsically random?

  • Dr.Chandrakant Naikodi asked a question in Complexity:
    What is the complexity of finding all possible combinations of numbers to reach a given sum?

    What is the complexity of finding all possible combinations of numbers to reach a given sum?

  • Anatoliy A. Khapugin added an answer in Articles:
    How can I download a research article?

    Please let me know - How can I download an article

    Anatoliy A. Khapugin · Mordovian State University

    Dear Vineet Sikarwar!
    What concrete articles do you want to download?

  • Filip Sabo added an answer in ERDAS:
    Can anyone tell me procedure to make a decision tree for Landuse Classification using GIS, ERDAS or other software?

    Actually i want to make make landuse using Supervised classification using ground truth data.But i faced a problem,many pixel of other crops they classify in Bare land. Therefore is it possible i made threshold or model that assign Specific pixel values to definite class. 

    Filip Sabo · University of Novi Sad

    You can also try with QUEST in ENVI (see attachment). Or, If you don't have ENVI you can use Erdas expert classification or knowledge engineer to build up your classification.