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  • Viljams Meliksetjans added an answer in Wind Power and Power Systems:
    What are Windmill technical part costs? Electrical generator, gearbox etc?

    Windmills with power of 800kW - 1 MW what could be the costs of their appliances inside the nacelle? I need just approximate numbers. One for offshore one for on-shore.  

    Viljams Meliksetjans

    Thanks for reply, I know about capital costs. But thats not the answer I wanted to read. What I wanted to know, because it is very hard to find the costs, is how much does inside appliances cost. By that I mean electrical generator, gearbox, jaw, inverter ect.  

  • Jagar Ali asked a question in BLOCKS:
    What is the best way to block the gas migration in cementing?

    How to achieve the minimum static gel strength?

  • Ranajee Ranajee added an answer in Time Series:
    Moving Averages of Stock Volumes really make sense?


    Till now I have been measuring the Volumes over moving averages of N-past days. And i realized how wrong I was.

    I feel, Volume is not a time-series data unlike price quotes. There is very high std deviation in volume data, sudden pulses, spikes and through are all there in volume data series. Moving averages captures trend effectivly if it's a time series.

    Hence, I feel the moving averages of Volumes for Any Time Period is not the right metric to compare with the Target day's Volumes.

    Any views please?

    Ranajee Ranajee

    Attaching a paper by Jonathan M. Karpoff for your reference. 

  • Markus Hösel added an answer in Organic Solar Cells:
    What are all Characterization needed for OPVs?

    We have been fabricating ITO/PEDOT:PSS/P3HT:PCBM/Al structure as a control for our system and I was wondering what are all tests that we need to completely characterize our fabricated structure. 

  • Sai Kalyan added an answer in EEGLAB:
    How can I report the power spectral density in EEGLAB as a number?

    i want to report power spectral density (PSD) in any band of EEG but when i plot the signal in EEGLAB, e.g in [4 8] Hz, in the figure the PSD mean is related to [0 8] Hz. (i use the tools menue and data statistics in matlab figure window)

    Sai Kalyan


    Is your question related to this following link?


  • María C. Fàbregas added an answer in Animal Behavior:
    What kind of interesting maladaptive behavior have you seen wildlife exhibit?

    I'm particularly interested in ecological traps and in unpublished situations. Thank you!

    María C. Fàbregas

    I have also observed the behavior Alfonso Balmoro mentioned here in South Africa.

  • Jan Andersen added an answer in Metrology:
    Extensiometer intercomparison - does anybody know about quality tests and intercomparrisons within extensiometers - length measurements?

    Does any laboratory arrange tests for intercomparison of extensiometers - or arrange cources with extensiometers?

    I have googled and asked arround but not found many possibilities right now.

    Kind regards,

    Jan/Metrology/FORCE Technology, Denmark.

    Jan Andersen
    Thank you. The measurement standard for extensiometers is ISO 9513, and the inspectors I support do these measurements often. - That is normally material testing machines - steel mostly. My problem is not measuring, it is to documet on a regulary basis that we do is correctly according to our measurement capabilities and procedures, because that is what I need to document according to our accreditation. I know that Aimo Pusa from Finland arranged something last year, but we could not participate. Probably I need to arrange it ourselves. Kind regards. Jan
  • Noor Haleem added an answer in Metal Matrix Composites:
    What is the best method to analyze the chemical composition of metal matrix composite? XRD analysis didn't give any change compared with base alloy.

    Please can any one help me?

    I fabricated four aluminum matrix composite with SiC and MgO, and I need the best method to find the exact chemical composition after casting.

    What is the best method to analyze the chemical composition of metal matrix composites?

    I used EDS, but the Si did not appear.

    Noor Haleem

    X-RF (Elemental Analyzer) is the best way to find the composition of you sample 

  • Avijit Ghosh asked a question in Budget:
    Do anyone have any suggestion regarding energy budget for FYM production?

    Do anyone have any suggestion regarding energy budget for FYM production?

  • Roberto Fernández de Luis added an answer in Inorganic Chemistry:
    ¿Does anyone Knows about any software that could compare the same asymmetric crystallographic unit and unit cells at different temperatures?

    ¿Does anyone Knows about any software that could compare the same asymmetric crystallographic unit and unit cells at different temperatures?

    Roberto Fernández de Luis

    Gracias Kenneth and Artem,

    Of course, I have calculate the bond distances and angles, even I have plot the thermal evolution of the cell parameters.

    I mean, after doing the strutural refinement with the single crystal data at diferent tempertaures I get the same structure (cif files), but at different temperatures. I don´t know how to overlap all the asymetric units and unit cells in the same picture to see visually which are the most important changes in the crystal structure.

  • Mohammad Taher Tahoori asked a question in Macrophage:
    Identification of Macrophage by immunocytochemistry?

    isolation of macrophages and confirmation of this cell in  liquid sample

  • Chapat Ludivine added an answer in Flow Cytometry:
    What is the best early T-cell activation marker for swine in Flow Cytometry?

    I will perform an intervention invivo and let the swine live for 10 hours and harvest my test samples(blood and Lymph node). i will perform Flow cytometry to look for change in the percentage of activated T-cells.

    I need recommendation of early activation antibodies to use.

    Chapat Ludivine

    Increase of CD4+CD8+ double positive cells can be a readout, it depends on the kind of activation

  • Shazia Aziz added an answer in English:
    How can I compare entry and exit level English for students on a UG course?

    Does anyone know an approach to compare students' UG entry level English language skills with their level after graduation? 

    I will know their IELTS score on entry.

    Shazia Aziz

    If you want to test their proficiency, you can conduct pretest and post test,asking them to write a composition in the beginning and one in the end of treatment/course and compare their scores using some standard testing score key

  • Tim C. Keener added an answer in Chemical Kinetics:
    How to find inlet duct velocity,inlet gas flow rate,gas density for a cyclone seperator?

    Feed of a Cyclone separator has 3 components, they are steam, moisture and STPP(Sodium Tri Poly Phosphate). To find Inlet duct area I'm having formula, A= inlet gas flow rate (kg/s)/(inlet duct velocity(m/s)*inlet gas density(kg/m3)). STPP is granular . For calculating the density, velocity and flow rate in above formula whether I need to include density, velocity and flow rate of STPP too. can anyone please explain how to calculate these three things for the above three components coming as feed.

    @117 deg Celsius feed,

    Water vapour(6.03kg/h;0.554kg/m3)

    steam(0.915 kg/h;1.026kg/m3)


    Tim C. Keener

    If it is a "dirty" gas stream you will have to use a S-Type pitot tube which is calibrated.  You will have to take your measurements upstream of the cyclone because the inlet may present problems in getting an accurate reading.  Use the upstream flow rate along with the molecular weight (see below) to find the mass flow rate.  You can then convert the flow rate for any changes in temperature, pressure, etc.,  in order to find a new volumetric flow rate at the cyclone entrance.  Use this data along with the dimensions of the cyclone to find the cyclone inlet velocity, etc.

    For the density, you will need to know the molecular constituents, not only the water vapor concentration.  Use an Orsat device to find the CO, CO2, O2, and the N2 by difference (this assumes the gas is from a combustion process), along with the water vapor percent to then calculate the flue gas molecular weight.  Then use the Ideal Gas Law to find the density.

  • Weina Wang added an answer in Quantum Mechanics:
    Can we use optB86b-vdw functional along with SOC?

    Dear RG user,


    I am working in 2D materials and new to the use of VASP software.

    For my studies i want to use OptB86b-vdw functional along with SOC. But, when i am using this functional + SOC, in my vasp output file, i am not able to find neither "Total vdW correction in eV" nor vdw_kernel.dat file is read during the calculation. But the keywords related to OptB86b-vdw
    GGA = MK
    PARAM1 = 0.1234
    PARAM2 = 1.0000
    AGGAC = 0.0000

    are read during the vasp calculations.

    But when i am using this functional without SOC, i am able to find both of them in my output file.

    Please help me to resolve this problem.

    Many thanks for help.

    with best regards,


    Weina Wang

    Hi, I also did the same calculations, and the same results reached. So i think it's not reasonable using optB86b-vdw functional along with SOC,becuase optB86b-vdw is a vdw interaction correction to standard DFT, an SOC is another correction to standard DFT. it can work using anyone of them,but it cannot woking mixing them.

    But I'm not sure. 

  • Luke Tudge added an answer in Prospective Memory:
    How can I make a prospective memory task more difficult?

    My ongoing task is to count the number of small and large squares, separately. My prospective memory task is to have participants respond with a different key press when they encounter a green square. 

    How can I make it harder for participants to identify PM targets (green squares) in this task?



  • Mostofa Shamim added an answer in DSC:
    Is there any explanation to non-dependency of fractional conversion of thermal reaction on heating rates?

    Generally, if we perform thermal decomposition reaction of a material with different heating rates, fractional conversion curves for different heating rates shift towards right with increase of heating rate. But when I perform thermal decomposition of cellulose with different heating rates, it does not follow the above rule. Can anyone provide me with any explanation to it?

    Mostofa Shamim

    Dear Dr. Kashmiri Deka,

    It is quite unexpected but interesting information. You have not provided the analysis details. I assume it is thermo-gravimetric analysis (as you mentioned thermal decomposition). Is it single stage or multi stage decomposition reaction ? Please provide the peak temperatures corresponding to different heating rates . Briefly provide the formula (or procedure) on how you get the fractional conversion data from a TG data.

  • Miguel Mompeán added an answer in Gaussian (Software):
    Could anybody explain me how i should write job file in Gaussian 09 to calculate UV spectrum with wavefunction methods like CC2 or ADC(2)?

    I would like to calculate UV spectrum in Gaussian 09 with wavefunction methods exclude simple HF but i could not find any information about how to write a job input file. Could anybody help me, please. Thank you. It is prefferable to calculate spectrum using cc2 method. 

    Miguel Mompeán

    I used them some time ago in Turbomole because they were not available in Gaussian (only TD, CIS & ZINDO)

  • Eva Hamilton added an answer in Atopic Dermatitis:
    Is there any insight for a curative treatment in the cause of pediatric atopic dermatitis?

    Apart from statutory moisturizers and palliative care leading to corticosteroidal suppresion or calcineurin- or Janus kinase targeted immunosupression, is there any hope on other kinase targets eg. TrkA in paper 25594427 attached, relevant to keratinocytes  or skin constituents with possibly less adverse effects? The catch usually is the chronic application setting and a reversible -take it, it stops- stop taking it, it comes back with a vengeance- feature, that would best be minimized.

    Is there any value in personalised prick/allegy screen test of an exhaustive antigen repertoire including clothing fibers, food constituents, urban pollutants, less established or suspected allergens?

    Taking another twist, eg. paper 26385242 attached, have any "Genetic variants and epigenetic alteration as tools for the molecular taxonomy of AD provided the background for personalized management" ?

    + 1 more attachment

    Eva Hamilton


  • Robert Kiss added an answer in Mind:
    The role of a drug's half-life in in vitro treatments and same half life in vitro and in vivo ?


    I test different drugs for cancer treatment in vitro for now. As I followed so far a previously set up protocol, it just came now into my mind, that the drugs half life might play a more important role than thought considering the duration of treatment before stopping and geting my result.  

    1) If my drug has a half-life of 50h, does it make sense to test it only 48h or do I definitely need to apply a treatment longer than the half life

    I think it is better to stay in these hours, to be sure to see the effect of all the drug, in real life, they might give a second dose after the first half-life time's over.....

    So if my drug has a half life of 6h, .. I'd rather do a shorter treatment or give a second/third dose ...right?

    2) The indicated drug's half -lives are usually referred to the half life in a human body, right ? Can I assume that it is the same in vitro ? I don't think so. 

    I would be very grateful for explanations, or links with references,

    Opinions in the lab are diverging....

    Robert Kiss

    To make short a potentially very long story, yes the half-life (HL) of your drug of interest is a crucial parameter to obtain in vivo anticancer activity.

    I do not think that you will obtainan "universal" response (accoding in your lab).

    The half-life of your drug in vitro does not relate to its counterpart in vivo because the metabolisation processes are not the same at all.

    You should perform murine and human hepatic microsome analyses to have an idea of the half-time of your drug.

    If the half-time is "long" (> 24 h in my experience), you should go with oral administration. If the half-time is short, you should go with i.v. administrations.

    Thus, you should determine the half-time of your drug in vivo following a single per os versus i.v. injection.

    If your per os availability is equal or higher than 25% of the i.v. bioavailability, you can go with oral administrations for your anticancer treatment. Otherwise i.v.

    If you go with oral administrations, you should go with one administration (very roughly) every half-time / 2.

    With an i.v. administration, every half-time.

    But you must first determine the maximal tolerated dose (MTD) in you rodent species.

    Once you have determine this MTD parameter (e.g. the dose that kills no mouse / rat in a group of 3-5 individuals after 28 days of observation, and without >20% loss of weight and "adverse clinical / behavioral effects" as compared to the control (untreated but receiving the vehicle + a "true" control group) group), you should administer your compound chronically about ten times after you have observable / measurable tumors every:

    * every HT/2 x MTD/2 if oral administrations

    * every HT x MTD/4.

    The idea is to cover tumor growth with a:

    * a one- to two-week treatment and 5-10 i.v. or oral administrations for rapid growing tumors 5-10 days after tumor grafting (depending on the model),

    * a three- to four-week treatment for slowly growing tumors. 

    These are parameters issued from my own experience and I guess that you will obtain soon a "bunch" of other responses!

    Good luck


  • Parida Aditya added an answer in Internet Studies:
    Do you get to feel a sense of attachment for the people you meet in a virtual community such as RG? How do you explain it?

    In an early, highly influential book in the field of Internet studies, The Virtual Community (1993), Howard Rheingold wrote that “the idea of a community accessible only via my computer screen sounded cold to me at first, but I learned quickly that people can feel passionately about e-mail and computer conferences. I’ve become one of them --added Rheingold--. I care about these people I met through my computer”.

    Online groups have some advantages over real, offline communities. A social networking site such as RG is joined by people from a unique diversity of backgrounds, countries and demographics. What brings us together is a common interest: research, science, a particular discipline or topic. We are able to communicate with each other and share and exchange information beyond constraints of space and time.

    But human relationships are not just a matter of information exchange. Feelings and trust are essential. Online communication has disadvantages in this respect, because it transmits much less nonverbal cues than face-to-face interaction: facial expressions, vocal intonations, gestures, postures and movements, on which mutual impressions and emotions are based.  

    To what extent can we talk about a “genuine community” if the relationships among its members lack at least some sense of attachment?

    “The poverty of social cues in computer-mediated communication inhibits interpersonal collaboration and trust”, said one of the main experts on social capital, Robert D. Putnam (Bowling Alone, 2000). Because of this, “computer-based groups are quicker [than real life groups] to reach an intellectual understanding of their shared problems”, but “they are much worse at generating the trust and reciprocity necessary to implement that understanding”. Putnam adds: “Building trust and goodwill is not easy in cyberspace”. Cheating would be more common online than offline.

    However, the current massive diffusion of social media has proven that “a major facet of social networking and part of its vast success” lies in “the communicational desires and motivations –the need to connect and relate to others” (Fenton, 2012, in Curran, J., et al.: Misunderstanding the Internet). This author notes that “social media have been invested with the ability to facilitate the development of strong relations with family members and friends and weaker relations with a range of acquaintances”.

    What are your views on these arguments?

    Parida Aditya

    RG while supporting the teaching and research community extremely well has also gradually enveloped into the some sort of common interest networking. Knowing persons of similar interest helps us to know with whom to interact and become friends. We get some good friends through this sort of networking and get opportunity of meeting some of them later. All these possible because what one writes in the virtual community normally reflects one's real personality. Once this bonding is developed, you feel attached with the person. The RG virtual community is growing well to create such bonding and doing a great job !!

  • P. Moncaleán added an answer in Botany:
    Pinus radiata proteins Data base?

    I would like to have access to a public data base of proteins  to compare expression of proteins in Pinus radiata. Someone can help me?

    P. Moncaleán

    Thank you very  much¡¡¡

    Best Regards

  • Michael Schnekenburger added an answer in Western Blot:
    ChIP trubleshootings in DNA detection with bioanalyzer

    I have performed a ChIP experiment and I have shared DNA ( 200-500 bp) and I checked if I have well immunoprecipitated the transcription factor of interest by Western Blot (and I succed in this). When I have tried to check the quantity and quality of the chromatin IP with the bioanalyzer It seems that I didn't succeed in immunoprecipitating the chromatin. Have someone already experienced this? Any suggestion? It may seems impossible not to have immunoprecipitated anything. (I have already tried ith the same protocol before and it worked so I don't what happens this time).

    Michael Schnekenburger

    How do you know you shared your DNA to 200-500 if not detected?

    Then the quantity of DNA immunoprecipitated by CHIP is quiet low, so it sounds difficult to see it without any amplification. Furthermore, how did you manage your DNA from IP to analyse it?

  • Abhishek Ranjan asked a question in Graphene:
    What can be the possible ways of increasing efficiency of solar cells using graphene?

    Graphene having excellent properties can be utiized for solar cells and thus efficiency of a solar cell can be increased.

  • Kebede Kassa added an answer in GHG emissions:
    How can Africa Benefit from the Cop21 Agreement?

    The International Community has adopted a commendable Agreement on tackling climate change in Paris last December. While the deal has a number of ambiguous provisions and non-binding provisions, the document is very progressive and has galvanized the consensus of all the UN member states, perhaps for the first time ever when such concurrence is achieved at this scale. 

    The question is how can Africa, with virtually no contribution to global warming in terms of GHG emission and given its very limited capacity to implement the Intended Nationally Determined Commitments (INDCs) benefit from the Agreement and take active role in its realization of the Paris Agreement in the coming 15 years.

    Kebede Kassa Tsegaye, PhD

    Team Leader for the Formulation of the IGAD Regional 

    Climate Change Strategy (IRCCS)

    Kebede Kassa

    I thank both of you for your contributions. Prof, I started writing my reflections on the population issue three days ago. However, lost the draft while in a hurry to board on a plane. You made interesting observations on that subject, but not many policy/decision-makers seem to be concerned so much with the demographic dynamics of climate change.

    Surely, scientists, notably the IPCC, have underscored the magnitude of the human factors. However, the emphasis seems to tilt on the economic side of the equation and less on the numbers. How can we explain this in the context of a world which will soon have to put food into 9 billion mouths? How can we plan for the population of tomorrow while we are not even able to meet the needs of the present generation even with the existing level of industrialization, agricultural intensification and increase exploitation of resources, particularly water and forest resources? 

    As someone having been involved in the population and development agenda (including RH, FP, etc) at regional and international levels, I always argue that these questions remain unaddressed, despite sporadic efforts by some of the UN agencies, NGOs, CSOs and IGOs. I therefore want the discussion to also revolve around these.


  • Brian Thomas Foley added an answer in NCBI:
    Can anyonw help me to find the complete sequence for plasmid pRG970?

    I am trying to find out the full length sequence for above mentioned plasmid. I could not find in ncbi. Can anyone please tell me which site I should use? I will be grateful for any valuable suggestions.

    Brian Thomas Foley

    The linked paper describes the construction of the plasmid.  It does not say they sequenced it.

  • Abhishek Sharma added an answer in Transgenic Plants:
    How to determine copy number of a gene via Absolute Real Time PCR?

    I want to check the copy number of a gene in transgenic plant through Absolute Real Time PCR ? Can any body suggest me the perfect way to determine copy number of Inserted gene through ABSOLUTE REAL TIME PCR ?

    Abhishek Sharma

    Thank you so much Sachin and Jack for your helpful suggestions. 

  • Krishnan Umachandran added an answer in Work-Life Balance:
    Can anyone please tell me what are the major challenges of work-life balance for care workers in UK? and suggest particularly relevant readings?

    With changing work patterns, workforce dynamics, pay and employment conditions, the flexible nature of care work is causing difficulties in maintaining work-life balance for the care workers in UK. Other than the common challenges, what are the special challenges that particularly may be faced only by the care workers? What could be the burning issue in the near future considering the national context?

    Krishnan Umachandran

    WHO Healthy Workplace Framework and Model: Background Document and Supporting Literature and Practices

    A healthy workplace is often seen as a very controlling environment, and it is often seen  one where the risks are controlled and inspections take place and hazards are prevented. But there is also the other understanding which is the health promoting environment where workplaces are giving opportunities for promoting health and preventing ill health.

  • Md Azizur Rahman asked a question in Nephrotic Syndrome:
    How can we measure appropriate weight of a child with nephrotic syndrome whose previous weight is not recorded ?

    To prevent steroid toxicity