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  • Askhat Sydikhov added an answer in Stereo Vision:
    4
    If i have a number of objects in an image, how do i use stereo vision to pick the biggest/largest very fast/within no time?

    Dear Experts,

    I am new to computer vision/stereo vision and i am wondering how i could use this to compare object sizes in an image to determine the largest/biggest within no time. Motivation should be how human eyes are able to tell the biggest/largest very fast without necessarily making pairwise comparisons.

    Thank you 

    Askhat Sydikhov

    Derdus M Kenga 

    I think this wouldn’t be as fast as recognition by a human. First things which will slow the program (imho):

    1. Detecting an objects

    2. Calculating their areas and comparing with each other

    For human size recognition is fast because we don't need to make accurate calculations. We have the "database" about sizes of common objects, so we can compare them with each other. Also we can detect an object and imagine the distance to these objects very fast.

  • Szun Szun Tay added an answer in Lentiviral Vectors:
    2
    Is the use of the Clontech Lenti-X 4th generation lentiviral system essential for lentiviral production using pLVX-AcGFP-C1 lentivectors?

    Having produced a fusion protein lentiviral vector (GFP in-frame with the gene of interest), using the Clontech pLVX-AcGFP-C1 vector I now want to produce these in to a lentiviral system. However the lab has the typical 3rd generation packaging and envelope plasmids, but this lentiviral vector from Clontech is apparently only compatible with their 4th generation Lenti-X system. So I was wondering if this is a real incompatibility issue, and if so we will go ahead and purchase the Lenti-X system, and thus does anyone have any experience with optimizing the Lenti-X system? Any thoughts or experience greatly appreciated.

    Szun Szun Tay

    I too am looking for some answers as to whether the Lenti-X expression vector is compatible with the 2nd or 3rd generation packaging system. 

    The Clontech datasheet says that their 4th generation Lenti-X supplies 5 plasmids: 1. pTre-gag-pro, 2. LTRHIV-vpr-pol, 3. pCMV-VSVG, 4. pMV-tet-off, 5. pTre-tat-ires-rev

    So tat is supplied on the 5th plasmid and should work with a 2nd generation lenti transfer vectors when pPAX2 + pMD2-G is supplied. Is this right?

    With regards to compatibility with 3rd generation expression vectors, they mentioned: We have not tested all vectors, but in principle, any HIV-1-based vector should be efficiently packaged using this system, and higher titers compared to a 3rd-generation packaging system should be obtained. For example, when a ZsGreen1 cassette was cloned into the pLenti6/V5 vector (Invitrogen)—a vector that lacks the WPRE and cPPT/CTS sequence elements and utilizes self-inactivating (SIN) LTRs—titers of >3 x 107 IFU/ml were obtained as determined by flow cytometry. Since the Lenti-X system utilizes Tat transactivation, HIV-1 LTR-based vectors will generate higher titers than those containing other LTRs. Vectors lacking WPRE and/or cPPT/CTS sequences yield consistently lower titers than Clontech® pLVX vectors.

    Invitrogen says The pLenti-DEST vectors contain the following elements:
    • Rous Sarcoma Virus (RSV) enhancer/promoter for Tat-independent
    production of viral mRNA in the producer cell line (Dull et al., 1998)
    Modified HIV-1 5′ and 3′ Long Terminal Repeats (LTR) for viral packaging and reverse transcription of the viral mRNA (Dull et al., 1998; Luciw, 1996)
    Note: The U3 region of the 3′ LTR is deleted (∆U3) and facilitates self-inactivation of
    the 5′ LTR after transduction to enhance the biosafety of the vector (Dull et al., 1998)
    • HIV-1 psi (Ψ) packaging sequence for viral packaging (Luciw, 1996)
    • HIV Rev response element (RRE) for Rev-dependent nuclear export of unspliced viral mRNA (Kjems et al., 1991; Malim et al., 1989)

    Any comments appreciated!

  • Gayathri Narasimhan asked a question in Palmitic Acid:
    New
    Anyone knows how to dissolve palmitic acid?

    Hi i am trying to dissolve palmitic acid to use it with cardiomyocytes. Can anyone help me out?

  • G. Sankaranarayanan added an answer in Engineering Thermodynamics:
    5
    Anyone have a thermal property table of isobutane R600a?

    organic heat recovery fluid

    G. Sankaranarayanan

    Dear Anoop,

    isobutane R600a? in ASHRAE handbook page 30.48

    in  2009 ASHRAE Handbook—Fundamentals (SI). available in website.

    bye

  • Vasudevan Sankar added an answer in ArcGIS:
    19
    How to detect LULC changes using ArcGIS?

    I am PhD student at University of Pretoria. Could you please assist me with tutorials for analyzing LULC changes for my study area using ArcGIS?  I do not have basic knowledge for GIS and Remote Sensing. Please email the tutorials to maggiemunthali2004@yahoo.com

    Vasudevan Sankar

    you may learn to image rectification, suppose you may have using with toposheets first do geo-rectification and then do with image to image rectification(toposheet and landsat imageries), until that you can be calculate  the change detection(area) whether gain or loss.

    all the best

  • Laboni Ahsan asked a question in Transdermal Patch:
    New
    Is there any pharmacy in India selling generic transdermal patches for Fentanyl?

    I need to buy some transdermal patches for Nicotine, Fentanyl, Nitroglycerin, Scopolamine, Sumatriptan generic one for research purpose. Preferably want to buy from India as I am going to visit there. Also anyone has done any experiment on this type of patches will be appreciated to contact.

  • Rajinder Singh Brar added an answer in Cancer Biology:
    2
    How we do cytoxicity for water preserved in plastic bottles?

    Can somebody tell me the best method for measuring cytotxicity for water preserved in plastic bottles?

    Rajinder Singh Brar

    Put sterilised water on growing tissue culture repeatedly and see cytopathic  affects like dead cells, less growth etc.

  • Kerrie Clover added an answer in Test Development:
    2
    Procedural Anxiety - what's the best measure/predictor?

    I'm looking to test / develop a screening tool to predict which patients are going to find medical procedures extremely stressful.

    We are working specifically with people with head and neck cancer about to undergo radiotherapy using an immobilisation mask.

    I'd love to hear from others who have tried to measure this concept - in oncology or elsewhere (eg CT / MRI). Medline doesn't appear to have a good keyword for this so it's a little hard to search.

    Interested in suggestions on the best measure of anxiety "on the day" - what are people's experienced of the State subscale of the STAI?

    Many thanks

    Kerrie Clover

    Thank you, very interesting!

  • Thomas Fitzgibbon added an answer in Dendrites:
    12
    Is this DiI staining valid or specific?

    I placed DiI crystals into the hilus of P10 mice horizontal sections (vibratome). I think the first image is from the CA3 region, and I can't tell if these are dendrites/axons or background, whereas the second image clearly has spines and does not belong near the CA3 region but is somewhere else in the cortex (can't tell right now where).

    + 1 more attachment

    Thomas Fitzgibbon

    in developing tissue you may also see a number of small processes on axons, or if near their terminal site these will normally be club like endings, some processes may look similar to spines..

  • Sagar Polisetti added an answer in Fatigue:
    2
    How to obtain the forces for an automotive component's fatigue test (rigidly clamped) from a FEM model where loads are applied using inertia relief?

    Inertia relief method is used to determine loads and estimate fatigue life for an automotive part. Would like to use these derived loads for fatigue testing of the part in a lab where the part would be rigidly clamped to the fixtures for loading. Usage of same loads directly lead to different reaction loads, load paths and hence different failure modes. How to derive the test loads from the FE model using inertia relief?

    Sagar Polisetti

    We're trying for a real time test in a lab.

  • Amila Zuko asked a question in 454 Sequencing:
    New
    What could be the reason for these strange chromatograms (see attachment) after DNA sequencing?

    Lately I'm getting failed DNA sequences and strange sequence peaks in my chromatograms when trying to sequence my plasmid (see attachments).

    With a previous mini prep sample, the following protocol did work (with the same primers). Now with the midi prep from the same sample/ and after a mini prep of an insert ligation into the same plasmid I'm having problems. I've tried this three times now. Very rarely I get short reactions (which correctly align with plasmid sequence), but mostly it fails. This is the protocol:

    -----

    For DNA I use purified plasmid: ± 500ng/ul; 1.90 260/280; 2.24 260/230. I also ran it on agarose gel (undigested and digested) and band sizes were as expected.   

    Primers: ± 20bp, Tm: 58-60C, 40-60% GC, I've avoided primers that make dimers/hairpins and I've checked if the primers have a single binding site on the plasmid

    For the PCR reaction: 500ng DNA, 3.2 uM primer, 5x Seq. Buffer, 1ul BigDye 3.1, filled up with water until 20ul

    Run PCR: 96C for 1', [96C for 10", 50C for 5" and 60C for 4']x25, 15C forever

    DNA purification: adding to the PCR reaction 2ul EDTA 125mM, 2ul NaOAc 3M, 70ul 100% EtOH. Invert and incubate 15' @ RT. Spin down 14000rpm @ 4C for 20'. Discard sup and rinse pellet with 200ul 70% EtOH. Spin down 14000rpm @ 4C for 5'. Discard sup and air-dry for 5'. Resuspend pellet with 20ul HiDi form amide and incubate 2' @ 95C. Transfer on ice for 3' and transfer to 96well. Input in ABI 3100-Avant sequencer and run the machine.

    Its not the machine since my colleagues do get good sequences and as far as I know we're using the same protocol. 

    -----

    I'm now sending these samples to a sequencing facility to run the reactions. But any ideas on why my reactions fail?

    + 1 more attachment

  • Marcus Wolff added an answer in Performing Arts:
    9
    What are the disadvantages of using western music notation to transcribe indigenous non-western ethnic music and what can be used as an alternative?

    Western music notation used widely in transcribing and notating non-western music. Well, it looks a media beside the oral transmission of music which can help grasping structure of a certain type of music, but it is not. Western music notation forces its limitations in transcriptions and through the history the notated version remains as the document or “original version” against changes take place in oral versions over time. It is in spite of modifications the written version already got through transcribing musical sound to written notation.

    Marcus Wolff

    I agree with many points posed by R. Jones, Tellef Kvifte and John Griffiths. Cognition and semiotics studies show that the western notation reflects only part of what is perceived by a western interpretant (to use a Peircean concept). So when dealing with non-European musical traditions, especially with complex and sophisticated traditions such as Persian and Indian classical music, we must ask ourselves if we want to colonize them by imposing a listening and an interpretation based on Western perceptions or if we want to consider the native notations and highlight their own perceptions (that can be different and revealing). In my case the experience of learning to read Indian notations was quite revealing about the conceptions of time and timbre, uncommon in Western music systems.

  • Francis Arthur Buttle asked a question in CRM:
    New
    Who is doing the best independent research on Social CRM?

    Social CRM is management of the customer life-cycle (acquisition, retention, development) through social media, such as Facebook, Twitter, LinkedIn and YouTube. Tech vendors and consultants have a vested interest in telling good news stories, but who is doing independent research? And what is being discovered?

  • Muttipati Appala Srinuvasu added an answer in k-means:
    5
    How can we implement normalization in k-means using bigdata?

    How can we implement normalization in k-means using bigdata?

    Muttipati Appala Srinuvasu

    Hi Pavithra.

    You can use Apache Heam for big data, below links will help you,

    + 1 more attachment

  • Stella Pitts added an answer in Behavioural Science:
    11
    Do students fear theory?

    In the social/behavioral sciences, many students (and many teachers) seem to have difficulty understanding what theory "is" and how to work with it. It seems strange that we use something all the time, yet have so little understanding of it. What is your experience? Is there a "fear of theory" and why?

    Stella Pitts

    I enjoy reading different kinds of theories. 

  • Marcelo Guimarães Silva added an answer in Plantar:
    2
    Foot plantar pressure system?

    Review about foot plantar pressure measurement system; 

    Best system?

    Different between systems?

    Marcelo Guimarães Silva

    In addition, I send another paper to you.

  • Paul-Emile Poleni asked a question in Yeasts:
    New
    How to perform a deletion mutation in S Pombe ?

    I tried to perform a deletion mutation in fission yeast using the 2 step PCR method. The target gene should be replaced by KanMX6.Can I have a reliable and detailed protocol?Thank you in advance for your help.

  • Tengfei Zhang added an answer in k-means:
    5
    Is c-means same as k-means in clustering algorithm context?

    The k-means concept states that every cluster must contain at least k elements.

    The c-means concept states that there should be exactly c number of clusters. 

    So, according to me these two concepts are different.

    Also, how do we categorize these two classes of algorithms? Means they come under supervised or unsupervised category?

    Tengfei Zhang

    Actually, there is no strict distinction between k-means and c-means recently. We can look at Google Scholar and use search for “fuzzy k-means” and "fuzzy c-means", there are 57900 and 74700 results respectively.

  • Muhammad Naeem Butt asked a question in ESL:
    New
    Can any one please suggest theoretical framework for research on ESL?

    I am preparing interview questions on ESL and require theoretical framework for its construction. i would be asking non-native students studying English in UMass about their experience pertaining to  curricula, teaching methodologies and interference of mother tongue during English language learning. 

  • Muhammad Naeem Butt asked a question in Second Language Acquisition:
    New
    Can you please send the work on "Introducing second language acquisition" by Saville Troike?

    book or article  the same 

  • Vishal Vijayan added an answer in Mangroves:
    11
    How mangroves control climate change?

    Mangroves control super cyclone  and also sequester carbon

    Vishal Vijayan

    Marine vegetated habitats including mangroves occupy only 0.2% of the ocean surface, but contribute 50% of carbon burial in marine sediments. Their canopies dissipate wave energy and high burial rates raise the seafloor, hence stabilizing the rising sea level, coastal flooding, erosion and wave action that are major allied with climate change.The restoration and conservation use of vegetated coastal habitats for coastal protection provide a promising strategy, delivering significant capacity for climate change mitigation. (PLEASE SEE THE ATTACHED ARTICLE FROM NATURE).

  • Mohammed B. Effat added an answer in Mobile Phones:
    3
    How to measure the capacity and data of charge and discharge of the recycled LiCoO2 ?

    We are investigating  the recycling of cathode and anode materials from spent mobile phone batteries containing LiCoO2 active materials.  First, we would like to know the experiments used to measure the capacity and data of charge and discharge of the recycled cathodic  LiCoO2 .  Second, we would like to cooperate with other researchers, who have this facility, to do the measurements of charge/discharge data.

    Mohammed B. Effat

    Salam Alykom Prof. Sayed

    I think this technique can be appropriate, please find:

    http://www.sciencedirect.com/science/article/pii/S0378775302000800

  • Graeme E Pile added an answer in Fertilizers:
    26
    What will be the fate of beneficial microbes if crops are nourished with chemical fertilizers alone?

    Nothing details

    Graeme E Pile

    Dr Hepperly & Kalra. In New Zealand we have been able to get dairy farmers to change the way they grow the grass which they graze their cows on. They normally apply urea every 20 days onto pastures the cows have just grazed. Now they apply fertilisers and biological products that stimulate the biology in the soil.

    We have been able to measure this by using the scientific method developed by Dr E Ingram, Orgeon. The soil food web counts the bacteria and Fungi in the soil and monitors the results over a 12 month period.

    We have seen the Fungi increase 20 times from very low levels. This was due to chemical fertilisers being applied to the dairy farmer over the last 10 years.

    Now the pastures have more clover in them and the cows are producing more milk with the farmer spending less money - making more profit.

    It is great to read you comments above to further understand how we have achieved these results. Look forward to further comments.

  • Paul Brown asked a question in Re-Sampling:
    New
    'Poptools' function call from within an excel macro?

    'Poptools' is a great add-in for MS Excel for simulation and re-sampling stats (www.poptools.org), but how can I call a Poptools function (e.g. Monte Carlo simulation) from within an Excel macro?

  • Rafik Karaman added an answer in Organic Chemistry:
    1
    What could be the effects of electron withdrawing groups over adsorption behavior?

    What could be the possible effects of electron with drawing groups ,if present in reactive dyes such as, in echriochrome black T.

    Rafik Karaman

    Dear Aiman,

    The following paper entitled " Comparative study on reaction selectivity of azo dye decolorization by Pseudomonas luteola" by Hsueh & Chen, JOURNAL OF HAZARDOUS MATERIALS 141(3):842-9 · APRIL 2007, studied the effect of electron withdrawing groups on the color (absorbance) of Echriochrome black T, methyl orange, Congo red and methyl red. The following abstract summarizes the study results:

    ABSTRACT

    This study is to inspect how the variation of molecular structures and functional groups present in our model azo dyes (i.e., Congo red, Eriochrome black T (EBT), methyl orange, and methyl red) affects biodecolorization capability of Pseudomonas luteola. The most viable decolorization was found at pH 7-9 and the optimal cellular age for the most effective decolorization was 7 days after static incubation in dye-free cultures. In decolorization, the maximal absorption wavelength in UV-vis spectra for the different dye-containing cultures shifted from visible light range towards the ultraviolet visible range. Methyl red was not decolorized in contrast to methyl orange, Congo red, and Eriochrome black T. The sulfonic group para to azo bond (-N=N-) in methyl orange was a strong electron-withdrawing group through resonance to cause an enhancement of color removal to be easily biodecolorized. As a charged carboxyl group on methyl red is at ortho position (i.e., in the proximity) to azo bond, this led to a complete inhibition to decolorization. However, decolorization of Congo red and EBT in the absence of charged group (e.g., hydroxy or amino group) near azo bond was not completely repressed like methyl red. Thus, the presence of electron-withdrawing groups as the substituents on azo dyes enhanced decolorization capability for biodegradability. In addition, Monod kinetic model provided better predictions to all dye decolorization at initial short periods of time due to negligible intermediate formed at initial short time duration, but significant intermediate accumulation took place at longer period of time. In contrast, the decolorization performances of methyl orange at 400ppm and EBT at 230ppm were significantly less than those predicted from the Monod kinetic model likely due to accumulated intermediates exceeding the threshold levels for feedback inhibition.

    To view the full publication, please use the following link:

    https://www.researchgate.net/publication/6839705_Comparative_study_on_reaction_selectivity_of_azo_dye_decolorization_by_Pseudomonas_luteola

    Hoping this will be helpful,

    Rafik

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: This study is to inspect how the variation of molecular structures and functional groups present in our model azo dyes (i.e., Congo red, Eriochrome black T (EBT), methyl orange, and methyl red) affects biodecolorization capability of Pseudomonas luteola. The most viable decolorization was found at pH 7-9 and the optimal cellular age for the most effective decolorization was 7 days after static incubation in dye-free cultures. In decolorization, the maximal absorption wavelength in UV-vis spectra for the different dye-containing cultures shifted from visible light range towards the ultraviolet visible range. Methyl red was not decolorized in contrast to methyl orange, Congo red, and Eriochrome black T. The sulfonic group para to azo bond (-N=N-) in methyl orange was a strong electron-withdrawing group through resonance to cause an enhancement of color removal to be easily biodecolorized. As a charged carboxyl group on methyl red is at ortho position (i.e., in the proximity) to azo bond, this led to a complete inhibition to decolorization. However, decolorization of Congo red and EBT in the absence of charged group (e.g., hydroxy or amino group) near azo bond was not completely repressed like methyl red. Thus, the presence of electron-withdrawing groups as the substituents on azo dyes enhanced decolorization capability for biodegradability. In addition, Monod kinetic model provided better predictions to all dye decolorization at initial short periods of time due to negligible intermediate formed at initial short time duration, but significant intermediate accumulation took place at longer period of time. In contrast, the decolorization performances of methyl orange at 400ppm and EBT at 230ppm were significantly less than those predicted from the Monod kinetic model likely due to accumulated intermediates exceeding the threshold levels for feedback inhibition.
      Full-text · Article · Apr 2007 · Journal of Hazardous Materials
  • Jazeel Hussein asked a question in Galaxy:
    New
    What is the rotation curves equation of early-type galaxies?

    can any one tell me how to calculate the rotation curves in early -type galaxies (elliptical-lenticullar)? can I use the same equation for spiral galaxies?

  • Chanakya P Rijal asked a question in Teaching and Learning:
    New
    Is there a conference going on anywhere with an aim to promote collaborative Teaching Learning in the Universities?

    What is collaborative teaching learning? What are its main elements? What benefits and impacts? Approaches for collaborative teaching learning? Environment required? Competence required?

  • Gabriel Garduño-Soto added an answer in Science Education:
    99+
    Why do science students get taught so little about the scientific method?
    Both at school and university in science the student is taught a lot about biology, physics or chemistry but very little about the different (good and bad) ways of doing science.

    Why is it so late in a person's scientific life when they are told about things like inductive reasoning and the better ideas of Karl Popper (falsificationism)?

    I found out about these things while reading "What is this thing called science" by Alan Chalmers.
    Gabriel Garduño-Soto

    Hello all.
    I have recently known about these Noam Chomsky talks, maybe it will contribute to understand at the roots the original question
    (Why do science students get taught so little about the scientific method? ) that is:
    To whom it matters that science students get taught about the scientific method?:

    https://www.youtube.com/watch?v=DbMP-cy1INA

    https://www.youtube.com/watch?v=XQceytpvKAc

  • Agarwal Priti asked a question in Paraformaldehyde:
    New
    What fixation will allow the visualization of GFP fluorescence on the membrane of germ cells in C. elegans gonad?

    I have tried using 1%, 2% and 4% paraformaldehyde. It retains the flourescence on the oocyte membrane and embryos, but is not at all good on the other germ cells within the gonad like meiotic and mitotic germ cells. Has anyone tried fixing membrane marker tagged with GFP within the gonad?

  • Rudy Situmeang added an answer in Gels:
    1
    How to prepare FTIR sample of gel beads?

    I want to analyze the gel beads on FTIR. The problem is that how to prepare the sample.

    Rudy Situmeang

    Hi Aditya,...You can see these articles (Iranian Polymer Journal
    17 (12), 2008, 899-906 ; and  Int. J. Pure Appl. Sci. Technol., 3(1) (2011), pp. 35-43) regarding on the FTIR analysis of gel beads.....good luck