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  • Ever tried using a Walz Diving-PAM to measure DO?

    Dear all,

    I am searching for a reliable method to measure DO in situ to study sponge primary productivity in the Caribbean. We have a Walz Diving-PAM available and I am wondering if there is a way to include oxygen measurements? Perhaps by connecting to a DO optode or by using ambient fluorescence? Your opinion is greatly appreciated!

    Kind regards,
    Mischa Streekstra

  • Tausif Alam added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Tausif Alam · University of Wisconsin–Madison

    Marc:

    "If (retinoid system) is ... a coherent functional entity which kind of experiments could be carried out to show fMRI images of it as in Fig 6?"

    The above assumes that the difference will be discernible by fMRI.

    Let's say you scanned the entire brain as someone waved about Arnold's fancy triangle through a slit and you saw nothing convincing in fMRI results. Would you conclude that Arnold's model is useless or completely invalid? 

  • Alia Amer Hegazy added an answer in Daylighting:
    How daylight and outside view can help long-stay patient's well being in hospital?

    How can we reduce the length of stay of patients through these 2 factors. Patients can be classified under any category but mostly "long stay patients" and their benefits.

    Alia Amer Hegazy · Helwan University

    Dear Franza, 
    this research discusses the link between day lighting and well being of patients from infection control perspective... if patients are safe, this will promote their well-being.. Hope it will be useful.

    Alia

  • Amanda Medeiros added an answer in Primer:
    How can I check the large DNA sequence (in an expression vector) ?

    Hi,

    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

    Amanda Medeiros · Universidade Federal do Rio Grande do Norte

    To be sure that all the gene will be covered and that you´ll have good quality sequencing data, I design one pair of primers to each 600 bp. Preferentially, with a overlap of around 100 bp between the amplicons generated by each pair of primers. For the first set of primers 5´, It´s interesting to use primers that can amplify since the MCS. 

    Good luck! 

  • Pavel Pazdera added an answer in Organic Chemistry:
    Can anyone suggest a solvent for this case?

    Regards.

    Needs to develop the synthesis of a particular compound and a intermediate includes in its structure a 12C hydrocarbon chain separating two pyrimidine rings. This compound is a insoluble solid in heptane, hexane, DMF, DMSO, chloroform. Can somebody suggest a solvent for this case? if possible using a solvent structurally simple to use as NMR-Solvent?

    Pavel Pazdera · Masaryk University

    and D2O or trifluoroacetic acid?

  • Asim Biswas added an answer in Centrifuges:
    Can anyone help me to determine the centrifuging time by stokes law?

    I am using Sorvall Legend RT+ centrifuge with 500 ml centrifuge bottle instead of tube. I need to determine centrifuging time by stokes law but I cant understand how I will find the distance from the surface of the liquid in the centrifuge tube to the center of the axis of the centrifuge and distance from the particles in the centrifuge tube to the center of the axis of the centrifuge.

    Asim Biswas · McGill University

     D=((18η ln (Rf /Ro ) )/((ρp - ρf )ω^2  ))^(1/2)/t^(1/2)

     Where η is the viscosity of the fluid

    ρf is the density of the fluid

    ρP is the density of the particle

    Ro is the starting radius of rotation

    Rf is the ending radius of rotation

    ω is the rotational speed (radians/second)

    t is arrival time at Rf (location of detector)

    From here you can calculate the diameter of the particle or the time it takes to settle the particles in the centrifuge tube.

  • Is it meaningful to fit an asymmetric distribution with multiple Gaussians?

    Dear researchers,

    This is a silly question but I have got to ask anyway.

    How would you parameterise an asymmetric peak? Would it be meaningless if I were to fit it with multiple Gaussians? Any suggestions on how I should extract my data?

    I have no experience 

    Thank you.

    Faizani Mohd-Noor · The University of Warwick

    Great, thank you Ollie! You're a great help, as always!

  • Pavel Pazdera added an answer in Amines:
    How can I prepare a schiff base of an amine with formaldehyde for the amine moiety that has a Boc protected amine also?

    I have moiety that having Boc protected amine as well as free amine and I want to prepare the shciff base of that free amine grp with formaldehyde?
    Reaction does not proceeding to completion, i can not use here acidic condition as it may lead to boc deprotection. I also tried to use basic condition but reaction not going to completion...so suggest me suitable reaction condition..

    Pavel Pazdera · Masaryk University

    for inspiration see using nonBroenstedt acid catalyst :https://www.researchgate.net/publication/267390365_Comparative_Studies_of_Catalytic_Application_of_Cerium%28III%29_Chloride_and_Resin_Supported_Cerium%28III%29_in_Domino_Syntheses_of_15-Benzodiazepine_and_13-Diazine_Skeletons

    or

    https://www.researchgate.net/publication/265959505_Synergism_of_Metal_and_Organocatalysis_in_Condensation_Reactions_of_Aromatic_Aldehydes_with_Anilines_Affording_Imines_Effect_of_Catalysts_on_the_Base_of_a_Supported_Cerium%28III%29_and_Proline

  • Usha Haley added an answer in National Culture:
    Does a tribe or national culture influence a company in deciding exporting and importing product?

    Our business management program is researching in cross culture decision making related with exporting and importing product around Asia,west europe,eastern europe,arab,africa and australia.

    We want to extends and apply hoefstede theory and eager to have international collaboration with other researcher around the world ask i stated above. As a started i need your opinion on this question  and possible joint research with our team.For pre-elemenary research power distance index cover most area of South East Asia and tendency of long term to short term as the influence of information and communication technology through mobile and social media.

    What do you think on tribe and nation culture that influence a company in a country decision to export and import product

    Usha Haley · West Virginia University

    I have added the cite to my answer.  The chapter deals with the building blocks of culture. 

  • G. Bothun added an answer in Climate Change:
    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? 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 is 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 quickfix 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 quickfixes 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.

    G. Bothun · University of Oregon

     And of course

    The proposed Incision across Nicaragua to allow even larger container ships to pass coupled with a likely navigable Arctic ocean for a couple of months per year will serve only to increase per capita consumption.

  • If a person had one serotype of dengue then gets Chikungunya virus, are they more likely to get hemorrhagic fever?

    I was in the field in S America when two team members got dengue, one for the first time. The professor had had another serotype in Africa and had severe hemorrhagic fever and the sheets were soaked in blood and the fever of 106 didn't break for over 5 days.

    Alfonso J. Rodriguez-Morales · Universidad Tecnológica de Pereira

    Interesting Terri. I have read and probably all you did, the first paper from Gorgas Institute in Panama on CHIK, which is in advance publication at AJTMH few days ago. In any case attached.

    Best wishes,

    Alfonso.

  • Ariel Linden added an answer in Tobit:
    How to test heteroscedasticity in tobit model using stata-12 and if found, how to solve it?

    how to test heteroscedasticity in tobit model using stata-12 and if found, how to solve it?

    Ariel Linden · University of Michigan

    there is a user written program in Stata called tobithetm: Tobit Multiplicative Heteroscedasticity Regression. You can download it from within Stata by typing:

    ssc install tobithetm

    There are other approaches to testing for heteroscedasticity in your data, but they are not straight-forward.

    I hope this helps

    Ariel

  • Susann Auer added an answer in cDNA:
    Does the q-PCR efficiency depend on the cDNA samples?

    I have had some preliminary evidences showing different q-PCR efficiencies (HKG and target genes) for different cDNA samples, using the same pair of primers. I reckon that, theoretically, efficiency of the HKG and target genes must be constant in every sample, but in my preliminary results, E encompasses from 85 to 95%. I'd like to know which could be the reason of the differences. RNA samples come from woody plant leaves. Thank you! 

    Susann Auer · Institute of Plant Physiology

    Dear Rafael,

    A difference from 85 to 95 % is rather small and therefore neglectable IMO. What you see could be a "natural" pipetting error or the normal degradation process of your cDNA rather than a real inhibitor.

    Keep in mind that cDNA degrades over time even when stored at -80°C. If you planned wisely you won' t freeze and thaw your samples but use a fresh aliqout for each qPCR. Using the same aliquot again for several PCRs and thawing it more than three times can definitely lower your PCR efficiency.

    I experienced that when I did semi-quantitative RT-PCR - samples that had been reused showed a weaker signal on the gel in each following PCR. Using a new aliquot for each PCR eliminated the problem. 

    As mentioned above of course there still could be a contamination in your samples. It is very likely that you have co-isolated non-plant RNA as well and that this alien RNA/cDNA interferes with your qPCR. This problem is well known from samples out of soil like roots - a tissue I am working on. Here, humins can cause trouble in the PCR. Of course secondary plant metabolites can be diadvantageous as well but I would start to think int that direction only if your RNA or efficiencies are really bad or you cannot detect any transcription at all - which is not the case for you.

  • Sophia Lavergne asked a question in Open Field:
    Searching for video tracking software for open field tests. Very low contrast b/w subjects and background, so need to track manually. Any suggestions?

    I performed and recorded these tests in the field so my subjects blend in very well with the forest floor -- making automatic detection nearly impossible. I had ok success with a PanLab trial but I'm wondering if there are any good (and hopefully open source) alternatives.

  • Raouf HAJJI added an answer in Cholesterol:
    Does anyone have experience in using statins for giant coronary artery aneurysm after Kawasaki disease?

    My patient had Kawasaki d. when he was 4yo, at that time, he had a giant aneurysm on left coronary artery, I've been using aspirin and anticoagultion since then, and now the aneurysm is calcifying (no thrombosis), his LDL cholesterol is 128mg/dl and he is on cholesterol diet since he was 5yo. Would anyone use statins for this patient?

    Raouf HAJJI · Sidi Bouzid Regional Hospital - Ibn Aljazzar Medicine Faculty of Sousse- Tunisia

    Dear F.Leite,

    It is a great and interesting question.

    It is a very difficult case for many reasons: 

    1. the patient age

    2. the rarety of the disease

    3. the severity of complication: the coronay anerysm

    4. the family background

    For all of these features, I think it is reasonable to try statins in this patient, especially when we look to the litterature where we found its very good impact because of its actions on lipid metabolism and endotheliul dysfunctin.

    see these links

    http://www.ncbi.nlm.nih.gov/pubmed/24599612

    http://www.ncbi.nlm.nih.gov/pubmed/25124974

    https://www.jstage.jst.go.jp/article/circj/72/10/72_CJ-08-0121/_pdf

    http://www.wjpch.com/article.asp?article_id=672

    I hope all these comments can be usefull for your patient.

    Best Regards,

  • Hamid Eslahi asked a question in Smart Metering:
    What is a smart meter?

    I would like some information on smart meters.

  • Tibor K. Pogány added an answer in Bessel Function:
    Does any one know how to compute definite integrals involving zero oreder first kind modified bessel function ?

    i want to compute integral of f(x) which is defined as

    f(x)=e(-ax)* I_0(b*(x^ 0.5))

    where

    I_0 is zero order first kind modified bessel function.

    and, the integral is done from x=0 to x=+\infinity

    i know the answer in the case of zero order first kind bessel finction (J_0), but im not sure to use the transformation from unmodified to modified. i would be really grateful to have your comments.

    Tibor K. Pogány · University of Rijeka

    Dear Omid, 

    the integral is actually the Laplace transform of the modified Bessel function $I_0(b \sqrt{x})$ (of zeroth order having argument $b \sqrt{x}$. Use the series representation of $I_0$, the exchange the order of summation and integration, and the result is (in TEX written):

    $$ \int_0^\infty e^{-ax} I_0(b \sqrt{x}) dx = a^{-1} e^{b^2/(4a)} .$$

    Regards, 

    Tibor

  • Cancer a mere matter of luck? Or is there something under-appreciated?

    It has been all over in the news lately: The majority of cancer is obtained by bad luck, not by lifestyle or inheritance. See attached. 

    Really? The data appear solid and they make sense, but the conclusion seems a bit premature: the observations are based on established risk factors in the USA and I assume (let the experts please come forward!) that these risk factors are based on occurrence. This means we do not see all those cases where the patient's immune system adequately takes care of the anomaly. 

    How does occurrence of cancer relate to failure of the patient's immune system, and can we monitor this based on adequate biomarkers? How will the statistics and the conclusions change when this factor is included in the analysis?

    Björn L.D.M. Brücher · Theodor Billroth Academy

    Thanks to Andrey and everyone. This discussion is highly appreciated, but I try focusing again on the main topic and I would be more happy, if in terms of important statements, the primary references will be provided, e.g. ”….they are secreted by 5-20% of dying cells”. Maybe I overlooked it, if so, I apologize.

    However I want focusing on the main aspects in terms of cancer as – as Jan wisely chose the title of this exchange “….is there something underestimated….”.

    I agree entirely there is a wide bi- or better multi-directional influence. I further agree that there is a difference in terms of in vitro versus in vivo aspects and for sure missing views on this may contribute to the missing of 80% of reproducibility in research in general. This part of the discussion is getting less clear, as some different aspects in cancer are mixed up:

    Carcinogenesis (the process how a cancer cell develops) with cancer (already developed cancer cell) and also not with its progress (growth as well as tumor spread). I may allow focusing at least my discussion by taking the different aspects of such into account, otherwise I would assume, the distinguished reader gets irritated. Getting back to your point I concentrate in the following on the process of development of cancer cells (carcinogenesis) and why the hype in terms of genomics, genes, chromosomal instability, polymorphisms did not help so far and won’t do so. The following show which important views had been completely underestimated:

    Either DNA, nor genes are blueprints only, those who consistently try educating future generations of scientists as well as in terms of critical thinking make a huge mistake. We should not concentrate on those marketing / promotional strategies anymore. For reminding us about the nonsense of that hype, we may get more down-to-earth by reminding us about the following:

    Measurements of the mutagenesis of cells grown in culture yield values of approximately 2×10−10 single base substitutions per nucleotide in DNA per cell division, or 1×10−7 mutations/gene/cell division. An even lower number has been demonstrated in cultured stem cells [Loeb LA: Endogenous carcinogenesis: molecular oncology into the twentyfirst century–presidential address. Cancer Res 1989, 49(20):5489–5496, Cervantes et al.: Embryonic stem cells and somatic cells differ in mutation frequency and type. Proc Natl Acad Sci U S A 2002, 99(6):3586–3590].

    Taking into account this very low mutation frequency, it seems reasonable to question whether or not the spontaneous as well as the assumed triggered mutation rate in normal cells is sufficient to generate the large numbers of genetic alterations observed in human cancer cells. Even if one were to assume that a cancer arises in a single stem cell, then the spontaneous mutation rate would only be adequate to account for less than one mutation per tumor which led to the hypothesis of the need for a “mutator phenotype”, which might induce many more mutations through the induction of genetic instability-a hypothesis not yet proven [Wogan GN et al.: Environmental and chemical carcinogenesis. Semin Cancer Biol 2004, 14(6): 473-486].

    The other aspect which – at least from my perspective – should be taken into account is understanding (or better starting to understand) the multi-directional information signaling – there is not just an in- to outside, there is an increasing understanding of out- to inside signaling:

    Enzymes can mutate even antibodies: apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3 (APOBEC3)) can also mutate antibodies by a yet-unidentified mechanism [Halemano K, Guo K, Heilman KJ, Barrett BS, Smith DS, Hasenkrug KJ, Santiago ML: Immunoglobulin somatic hypermutation by APOBEC3/Rfv3 during retroviral infection. Proc Natl Acad Sci USA 2014;111:7759-7764].

    We already know the mechanism of gene control by long non-coding RNA (lncRNAs) mediated repressor occlusion; this group also identified the COX-2-lncRNA, PACER, as a new potential target for COX-2-modulation in inflammation and cancer [Kramczyk et al. Elife. 2014 Apr 29;3:e01776]. Just one more argument: Lysyl oxidase-like 2 is critical to tumor microenvironment (and metastatic niche formation in hepatocellular carcinoma) [Hepatology 2014;60:1645–1658]. Please be aware that LOX modulates the ECM and also cell migration and growth [Mammoto T, Jiang E, Jiang A, Mammoto A: ECM structure and tissue stiffness control postnatal lung development through the LRP5-Tie2 signaling system. Am J Respir Mol Biol 2013,  49(6):1009–1018].

    Why is this signaling so important?

    In this regard it is important taking the studies in the blind mole rat, Spalax, into account: such revealed that the fibroblasts in this species suppress the growth of human cancer cells in vitro [Manov et al: Pronounced cancer resistance in a subterranean rodent, the blind mole-rat, Spalax: in vivo and in vitro evidence. BMC Biol 2013, 11:91] and decrease the activity of hyaluronan synthase 2 [Tian et al.: High-molecular-mass hyaluronan mediates the cancer resistance of the naked mole rat. Nature 2013, 499(7458):346–349.]. This species was also resistant to chemical carcinogenesis (!!).

    These data constitute evidence that fibrosis is necessary for establishing the PCN (pre cancerous niche) stage, an intermediate stage on the path from a normal cell to a cancer cell. Additionally, it has been shown that necrotic wounds induced in Spalax by chemical carcinogens heal with no sign of malignancy [Manov et al: Pronounced cancer resistance in a subterranean rodent, the blind mole-rat, Spalax: in vivo and in vitro evidence. BMC Biol 2013, 11:91], a finding that supports our hypothesis that the PCN stage is key to the transformation of a normal cell to a cancer cell. So, if a species (as Spalax) lives for about 30 years and does not develop cancer, even when exposed to known chemical carcinogens (!) someone may take into account that in the absence of the pre-cancerous niche, no cancer cells can form.
     

    It makes – at least to me – not much sense still trying concentrating discussions in terms of carcinogenesis on genes, chromosomes, polymorphisms, instabilities, (I also provided the number prior within this discussion). It should not be a fitting in of the genomic or somatic mutation theory our priority, it should be our critical thinking for getting into the understanding carcinogenesis. For this, someone needs the willingness seeing these variables (genes, chromosomes, polymorphisms, instabilities) not as holy grails anymore.

  • Mary C R Wilson added an answer in Grounded Theory:
    What is the best way to operationalize grounded theory?

    Since many conceptual thoughts are embedded in memos ( which -according to Charmaz- remain private and unshared), I wonder how to best operationalize the steps taken before the Integration of the abstract analyses in the grounded theory?

    You asked about how memos had been incorporated into PhD theses. It was 10 years since I wrote this but if it is of any relevance to your question, this is from my Methods chapter; I was using constructivist GT:

    " . . . I wrote memos to record my ideas about the patterns emerging; these started life as hand-written jottings that I returned to, with further thoughts as they occurred to me. This has been termed by Charmaz389 as an 'on-going dialogue with self' [:1169] which, she suggests, helps the researcher to rise above individual cases and identify patterns [:43]392. After I had accumulated a collection of memos, I added them to my research diary."

    I then gave an example of two of a series of memos as a (text) box, thereby acknowledging the recording - and subsequent use - of memos, but did not use 'raw' memos as data for my thesis.

    398. Sandelowski M. Focus on qualitative methods: sample size in qualitative research. Research in Nursing and Health 1995; 18:179-183.

    392. Charmaz K. Grounded theory. In: Smith JA, Harré R, Van Langenhove N, editors. Rethinking Methods in Psychology. London: Sage Publications; 1995: 27-45.

    But I'm not sure that this really answers your question,

    Mary

  • Kesavan Ekambaram asked a question in Gromacs:
    How to find which dssp version works with gromacs 5.0.2 version ?

    I have installed gromacs 5.0.2 version and tried to perform secondary structure analysis ,but there was a fatal error showing use -ver option . i tried using the -ver 2 in the command line still its showing same error . Finally i installed dssp 2.0.4 version in usr/local/bin/dssp but still the error persists .

  • Francisca Okeke asked a question in Climate Change:
    What should we worry about in global climate change?

    What is the root cause of climate change? how is the change affecting human lives on earth?

  • Inês Pita added an answer in Protein Fractionation:
    Is anyone familiar with a protein concentration method for western blotting?

    Hello!

    I'm using a new protocol for subcelular fractioning for rat striatum and frontal cortex. Unfortunately, I'm obtaining little protein in fractions (nuclear, sinaptosomal and non-sinaptosomal), especially in the striatum. I already used a pool of the cerebral regions but it's not enough.

    Thank you

    Inês Pita

    Inês Pita · University of Coimbra

     Christopher, the TCA protocol is aplyed after tissue homogenization, right? After TCA I'll do the protein quantification followed by denaturation , correct?

  • When it comes to simultaneity is Einstein correct or is Dingle correct?

    Albert Einstein claimed in 1905 that a single event can occur simultaneously at different times within two inertial reference frames moving relative to one another. In 1950 Herbert Dingle argued that different times cannot be simultaneous. I have analysed this conflict by deriving the Lorentz equations using both points of view. According to this analysis Dingle must be correct. See youtube presentation of this analysis at  https://youtu.be/4XLYzhHQ64Y

    Valentin Danci · Science

    Charles wrote: "inertially connected? and green ideas sleep furiously I suppose. Actually clocks are used to define reference frames."

    No, clocks cannot be used to define anything by themselves. It's the inertial motion + a coordinate system, which together define an inertial reference frame.

    >> "- a light ray - which cannot be connected, nor linked, not correlated with
    >> any other reference frame, because light is an independent phenomenon."

    "Ahh, now we have it. A light ray is not emitted by its source. Well you have managed to bring down the whole of technology in the modern world with that one, Valentin."

    No, it's only you who managed to show once again you poor understanding of the simplest written language. Plus you showed again your ignorance about Physics, as light's propagation through space does not depend on the motion of the emitter. That means for an observer who receives a light pulse that he cannot estimate where the source actually is located, at the very moment of reception.

  • How can I improve short circuit current in Dye Sensitized Solar Cells?

    The solar cells we are making are having good voltage arouen 350 to 500mV but current is low in microAmpere. How to improve current. we are using low cost dyes such as rose bengal and eosing y.

    Eyüp Fahri Keskenler · Recep Tayyip Erdoğan Üniversitesi

    You may use wafer thickness as 10-25 nm.

  • Yolani Furunek asked a question in Cowpea:
    What is the effect of cowpea and lablab residues in soil fertility?

    what factors will influence the decomposition of the residues ?

  • Emily Hopewell asked a question in Irradiation:
    Has anyone converted from 137Cs irradiation to X-Ray irradiation? If so, what kind of validations were performed?

    I am looking for comparison studies between 137Cs and X-ray radiation sources/

  • Prerna Bansal added an answer in FASTA:
    Is it correct to perform homology modelling of a particular length of fasta sequence rather complete fasta sequence?

    is it correct to perform homolgy modelling of a particular length of fasta sequence rather complete fasta sequence?

    Prerna Bansal · University of Delhi

    its becoz the rest part of fasta sequence does not have suitable template to make model while the other for which it is available has been found to be crucial in its activity. thats y need to do homology modelling. so is it correct...?

  • What is physical meaning of the energy bandgap of the semiconductor materials?

    According to the vegard's law, the band gap of Sin(1-x)Gas can be varied by changing the ratio of InAs. I would like then to know if the bandgap energy is linked to the fracture binding energy of semiconductor materials.

    Eyüp Fahri Keskenler · Recep Tayyip Erdoğan Üniversitesi

    Basically, it is associated with bonds of elements. If you would like to break an electron in the bond, you should give an energy to electron which is enough to break it in crytal structure. This energy is Eg. Indirectly you can change this value as dopped a different ionic radii atom etc.