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  • Moumita Sarkar added an answer in Gene Amplification:
    Can anyone help me out with amplification of full length 3Kb fragment of a mouse gene?

    Hello dear all,

    I am trying to amplify a 3kb fragment of a mouse gene through mouse gDNA using KOD Taq Pol. Initially I did not get any amplification but later after I played around through varied gradient, I got an amplification of 1.5Kb which I then cloned and sequenced and found that the obtained fragment was matching with the partial second half region of desired 3kb fragment. Now I have been trying to amplify the first half of  desired 3kb fragment using reverse primer designed within the already amplified second half fragment and forward primer designed using the reference nucleotide seuence file, but I am not getting the any amplification. Kindly help me out with different approaches to try for and solve this issue... 

    Moumita Sarkar

    I too feel that you may have problems with  the integrity of the template DNA which is preventing the amplification of the 3 kb. Set your PCR reaction with higher annealing temperatures. Also redesign another set of  primers.

  • Victoria Wu added an answer in Matrigel:
    MCF10A acini recovery from matrigel for RNA isolation?


    I am trying to recover my acini for RNA isolation from matrigel. However, even after incubation in the Corning® Cell Recovery Solution (Product #354253), I find that there is "goop" or gel when I try to pellet my cells. The incubation was on ice for 1h. The centrifugation was at 200g for 5 min at 4 deg. I am unable, as a result, to recover the acini efficiently for lysis and RNA isolation. Any advice would be appreciated.

    Victoria Wu

    Sorry I misunderstood the question, have you tried to trypsinze the cells off of the matrix?  You can try to incubate in trypsin, shake to loosen the cells from the matrix, check under the scope to see if you see any cells/clumps being released and if you do suck off the trypsin with the cells and then spin down to recover the cells.

  • Jan Engmann added an answer in Elevated Temperature:
    Is there Mark-Houwink parameters for polysaccharides in DMSO at 40 °C?

    Dear all,

    is there any literature about the Mark-Houwink parameters (K and a) for polysaccharides (pullulan, amylose, or similar) in DMSO at elevated temperatures (mostly 30 or 40 °C)?

    Thanks in advance.

    Jan Engmann

    If not readily available in the published literature, I would be surprised if Mark-Houwink parameters for DMSO are easy to find. Walstra ("Physical Chemistry of Foods") and Lapasin & Pricl ("Rheology of Industrial Polysaccharides") give M-W parameters for polysaccharides in aqueous solution which you can use as guidance, of course under the assumption that solvent quality of DMSO is comparable to that of water for your solutes.

  • Stephen Politzer-Ahles added an answer in Interlinguistics:
    What languages share the same characteristics with Basque in case of numerals and nouns?

    In Basque when you say "five euros" you do not add the plural morpheme to the noun which follows the number, thus you say "bost euroØ" (i.e. five euro). In questions when you are asking the quantity, you do not need any plural marking either, e.g. "Zenbat etxeØ dago?" (i.e. "How many apple?"). I would like to know what languages share the same characteristics with Basque.

    Stephen Politzer-Ahles

    Chinese languages and Turkic languages

  • Hein Van Gils added an answer in Marine Ecosystems:
    How can I measure the environmental impact of the coastal cities in the coastal and marine ecosystems in a easy and fast way?

    I need to measure the impact of coastal cities in the coastal-marine ecosystems but I am searching the best way to do it  fast and easy.

    What do you recomend? What are the possibilities in terms of practical and theorical areas, methodologies, etc.?

    Please, recommend me aspects to consider.

    Thanks in advance...

    Hein Van Gils

    From the perspective of a city planner and/or EIA practitioner: raw (untreated) sewage (e.g Dakar today; until 20 years ago most European coastal cities). Luckily sewage dumping backfires in case of affluent residents or tourist at city beaches.

    Do not forget the positives. For example, seals (San Francisco, Walvis Bay and Cape Town) and penguins (Cape Town) may thrive in cities/harbours, 

  • Papiya Chakraborty added an answer in Cellular Immunology:
    For polarizing monocytes to M2 macrophage using tumor cell supernatant, how long it should be cultured?

    For polarizing monocytes to M2 macrophage using tumor cell supernatant, how long it should be cultured? I read somewhere that it should be polarized for 6 days but is that the ideal culture period? If yes then how often the media should be changed? Please suggest!

    Papiya Chakraborty

    Thank you for your suggestions.

  • Yuri Mirgorod added an answer in Propolis:
    Is there anyone who works on the oil and oil in water emulsions?

    I would like to work on fish oil and propolis emulsions. What is the best extraction method to prepare this emulsion? 

    Yuri Mirgorod

     Dear IIknur:

    Your system will work well polyethylene oxide gel. The molar mass PEO and the ratio of the components should be selected experimentally according to your task.

    Best Regards.

  • Sulthan A asked a question in Stock Pricing:
    How Stock returns/returns becomes a continuous variable?

    It is known that the stock prices or value of other financial instruments has its own tick size and so they are discrete variable in nature. But I read that the returns of stock market is a continuous variable and not sure how?

    Because, the return is the difference of the same stock price. so, still it is the difference of the tick size which also remains to be a certain number. So how could a stock returns becomes a continuous variable.

    source where i read stock returns are continuous: http://financial-dictionary.thefreedictionary.com/Discrete+random+variable

  • Vijaya Bodiga asked a question in Nanoemulsions:
    Which type of palm kernel oil esters can be used for nanoemulsions?. Please specify the source?

    which esters (Methyl/epoxy alkyl / PEG-6 ester) are best for preparing palm kernel oil ester for nanoemulsions using spontaneous emulsification method?

  • Vijaya Bodiga asked a question in Nanoemulsions:
    Which type of palm kernel oil esters can be used for nanoemulsions?. Please specify the source?

    which esters (Methyl/epoxy alkyl / PEG-6 ester) are best for preparing palm kernel oil ester for nanoemulsions using spontaneous emulsification method?

  • Sarabjeet kour Sudan added an answer in Protein Expression:
    What can be the reason of not getting induction in expression hosts ??

    I am trying to clone a gene and go for protein expression. But it is not getting induced . Although  I checked my insert by digestion and then by sequencing before doing transformation in expression hosts but still no results . please suggest me 

    Sarabjeet kour Sudan

    ohk i will do it definitely and then proceed further .......

  • Romer Castillo added an answer in Higher Education:
    What are the main topics in a description of a higher education system?

    When you look at a higher education system, which aspects build the story of that system?

    Romer Castillo

    Higher education system can be described by the inputs (e.g. enrollment, school facilities, instruction, faculty, etc.) and/or by the outcomes (e.g. success of graduates in professional examinations, employment, etc.). Hence, higher education system can be inputs-based, outcomes-based or a mixture of the two.

  • Praman Kumar added an answer in Water Resources:
    How can illegal mining be controlled to manage natural water resources?

    Protection of water resources.

    management of wetlands .

    improper land use.

    Praman Kumar

    The question of stopping illegal mining would be in the interest of the politicians and if any law exists for the protection of natural habitats/resources and the politicians are willing as well then our task should be identifying the areas of illegal mining for which the technology - aerial imagery can be useful. The approved miners may sometimes exceed their boundaries with or without knowledge and even this will be illegal. first with the surveyor the approved sites are to be demarcated on the site according to the coordinates and the aerial imagery studies further helps in unapproved sites (illegal mining) and the approved exceeding their boundaries.

    further such people have to be penalized as per the laws and further controls like employing the local tribes/people in safeguarding their resources and if the same people are involved in illegal mining then they should be counseled and alternative opportunities have to be provided.

  • Atiqa Khan asked a question in TASSEL:
    How to perform confusion matrix using ROIs in ENVI 52?

    I have ROIs from a high resolution imagery and i want it to compare with Tasseled cap/NDVI/NDBI. My question if we analyse the pixel values (lets say, 0.187) of Tasseled cap/NDVI/NDBI against those ROIs, and then classify these Tasseled cap/NDVI/NDBI using "Raster color slice in ENVI", then generated confusion matrix/kappa coefficient in this way is consider as "Correct" or not?

    This process is acceptable scientifically or not? 

  • Aniket Sengupta added an answer in Cloning:
    How does good quality cDNA appear on a gel?
    I am unable to amplify the band of my interest from the new cDNA, whereas the old cDNA used to give a very prominent band at 60 degrees. I have repeated the reaction umpteen number of times, with all the new reagents but no amplification still. What could be the problem?
    Aniket Sengupta

    Also, if you have already not, ensure that the starting amount and quality of RNA for both cDNA synthesis reactions are comparable. If the transcript is of low abundance and one tube had a much lesser RNA to start with, you might just miss the transcript.

  • Yuan-Yeu Yau added an answer in Arabidopsis:
    How can I control fungus in soil during growing of arabidopsis?

    How can I control fungus in soil during growing of arabidopsis?
    arabidopsis grown in plant growth room

    Yuan-Yeu Yau

    Hi Rahul,

    Attached is a PDF regarding the ins and outs of how to grow Arabidopsis. PDF is prepared by ABRC (Arabidopsis Biological Resource Center). https://abrc.osu.edu/seed-handling

  • Akram Abdulameer Abbood Al-Khazzar added an answer in Photovoltaic Systems:
    PV vs CSP solar technologies?

    The energy demand has increased exponentially during the last decade and should reach 50 TWh in 2050. It is admitted that in the future, renewable energy sources should replace fossil fuels and reduce GHGs emissions which are responsible of climate change. The huge solar potential  is pushing investments toward CSP and PV technologies [1]. The two technologies are now in an open competition but PV is still leading with a comfortable ranking as a third source of Renewable energy. CSP technology still needs technical and economical improvement although it’s thermodynamically consistent.

    Akram Abdulameer Abbood Al-Khazzar





  • Vladimir Puzovic asked a question in Athletes:
    Knee degenerative changes in young athletes?

    Dear professors and colleagues,

    Is it common that MRI of knee of female athletes aged 17-20 years, beside different acute injuries, shows degenerative changes? In last 6 months majority of female athletes of mentioned ages, that I needed to recover had them.

    If the MRI of 17 years old female athlete shows non injured ACL but with degenerative changes, what is the risk of ACL rupture, is it drastically increased... ?

    Every discussion and advice is welcome.



  • Khaled Tafran added an answer in Democracy:
    Does freedom (democracy) promotes individuals' altruism and/ or volunteerism?

    Does freedom (democracy) promote individuals' altruism and/ or volunteerism?


    any empirical evidence?

    Khaled Tafran

    hi Renzo Bianchi,

    i use freedom house definition; political freedom and civil liberties.

  • Daniel Einor added an answer in Psychology:
    How may I compute a meta-analysis in STATA when only odd ratios are provided?

    Hi everyone,

    I'm currently attempting to run a meta-analysis using STATA but some articles I have only provided OR so I converted the 2 x 2 contingency from the other articles into an OR also. However, I don't have the 95% CI calculated.

    I am interested in understanding what commands I should input into STATA to run it. 

    Thank you!

    Daniel Einor

    Hey, Hatty!

    I also found the CampbellCollaboration Website quite useful for converting various effect sizes. these guys rock!  http://www.campbellcollaboration.org/resources/effect_size_input.php


  • Smita Chaudhry added an answer in Survey Methods:
    Can independent continuous variable be used along with manipulated categorical variables in an experimental design?

    I have some doubts regarding designing an experiment with manipulated and un-manipulated independent variables. I would be grateful to get your inputs and suggestions.

    I am using  an experimental vignette survey method, using a 2 * 2 between subjects design. There are three independent variables out of which two are being manipulated and are categorical variables. The third independent variables is a continuous variable which I am measuring through items based on a description in the questionnaire. There are four versions of the questionnaire based on the two manipulated variables. All are measuring the same independent variable (based on the same description in all versions) along with the dependent variable.

    The independent continuous variable is of primary interest for the research.The focus is on finding the impact of the manipulated variables on the relation between independent and dependent variable.

    Can I use such a design?

    I have not come across any papers which use a similar design. It would be great if you can refer some similar papers and give your feedback,

    Many Thanks


    Smita Chaudhry

    Thanks a lot for your feedback. It has been really valuable !

  • Moumita Sarkar added an answer in Western Blot Analysis:
    How can I remove irregular spots in western blot result ?

    Here my western blot result.

    I always get similar problems.

    How can I remove the irregular spots?

    Moumita Sarkar

    I agree with Sibylle and with Anastasia regarding the ECL. You may restandarize the blocking---like increasing the blocking time or concentration of the blocking reagent. Also look into the washing steps after 2ndary antibody incubation.

  • Shagos G S added an answer in PET:
    What would cause false positive PET in vertebra?

    new diagnosis oropharyngeal cancer with one small area of uptake at T12, unlikely to be metastatic but trying to explain other possible reasons for positive PET

    Shagos G S

    Inflammed schmorl's node,severe degenerative changes,recent osteoporotic collapse,traumatic fracture,facet joint arthropathy,infection etc are few causes of non metastatic uptake in spine in FDG PET scan.

  • Vasu Duraisamy added an answer in Sustainable Agriculture:
    The soils are calcareous and sodic. Cotton and Red gram major rain field crops. Groundwater is poor in quality. What could be the management options?

    The yield levels of crops are also low

    Vasu Duraisamy

    @ Dr. Subba Rao

    Dear Sir,

    Many thanks for your valuable suggestions. The major problem in the study area (Thimmajipet mandal, Mahabubnagar district) is water availability. The MAR is around 450-550 mm and poorly distributed. Groundwater is the only source of irrigation and water harvesting is a tough ask because of poor rainfall. Since the water availability is very low the use of amendments like gypsum is a challenge and the calcareousness aggravates the problem. Anyhow, I will try to weigh in your suggestions and explore the possibility of implementing to a maximum possible extent.

    Thanks and regards. 

  • Mihai Prunescu added an answer in Decoherence:
    Is there a Wave Function of the Universe?

    Different physicists disagree on whether there is such a thing as the wave function of the universe.

    - In favor of its existence is the fact that, in the Big Bang picture, all particles (and hence downstream objects) were correlated at the inception of the Universe, and a correlation that has existed at some point in the past ever so loosely continues thereafter since full decoherence never truly sets in. A number of pictures  - Ghirardi-Rimini-Weber, Bohm, even Hugh Everett, et al., - demand that  the existence of the wave function of the universe, denoted Ψ(U).

    - Two main categories of objection however belie its existence.

    The first category ultimately boils down to a not very solid rejection of non-separability, i.e. to an argument that a full separation between an observer and an observed must always be upheld if any observation or measure is to be objectively valid, and a wave function ascertainable.

    The second argument is more compelling, and says that if Ψ exists, then Ψ(U)=Ψ(Ψ,U) in a closed, self-referential loop. Ψ has thereby become an non-observable, unknowable, and as such better relegated to the realm of metaphysics than physics.

    What say you?

    Mihai Prunescu

    I have no idea about the probability of a black hole collision in an interval of 100 earth years, but it looks that there are also many black holes:


    I even wonder if by the estimation of dark matter the black holes have been considered or not. Are they counted to normal matter or to dark matter? The phrase "most of them are unknown and cannot be localized" is not ecouraging at all.

  • Pouya Kamalinejad added an answer in CMOS:
    What is the Best way to connect the bulk terminal in diode connected PMOS?

    I am trying out a CMOS rectifier. I did built a diode connected half wave rectifier and it works fine.

    The doubt which I am getting now is, how important is the bulk connection in diode connected transistor (PMOS).

    Consider a PMOS with Gate-drain (GD) connected, and the bulk connected to source terminal (SB). Now the question is which of these connection form the P and N terminal of the diode and how is it determined.

    Which junction in transistor, the diode characteristic is used. Is it drain-bulk, source-bulk of gatedrain-source junction.
    Can anyone brief on it ?

    What is the Best way to connect the bulk in diode connected PMOS for rectifier application? - ResearchGate. Available from: https://www.researchgate.net/post/what_is_the_Best_way_to_connect_the_bulk_in_diode_connected_PMOS_for_rectifier_application [accessed Feb 8, 2016].

    Pouya Kamalinejad

    Herman's answer explains it clearly.

    Just to add a few quick points:

    In case of a rectifier, the voltage on the drain side will go higher than the source for some portion of the negative cycle of the input (though by definition, it is not drain any more, lets still call it "drain" by convention as it is tied to the gate). 

    Basically there is not a short answer as to which side is a better option to connect your the terminal to.

    - For a simple design where you do not care much about the turn-on voltage of your diode (Vth of PMOS), simply connecting it to the output side (source) is the safest way to go.

    -If your input level is small and you want to partially cancel the threshold of the diode connected PMOS switches/diodes, you may want to tie it to a lower voltage. The catch is, such static threshold cancellation (i.e., connecting body to a low voltage) although helps in forward conduction cycle, increases the leakage (due to lower Vth) in reverse conduction. In extreme cases, what you lose is more than what you gain. The best approach is to set the body voltage dynamically and according to S-D voltage. Take a look at differential-drive rectifiers where you can connect the gate and the body of switches to the complementary (180 shifted version) of input. 

    Short answer:

    1- High input level where turn-on voltage is not a concern: connect to output side(intermediate output for multi-stage)

    2- Small input level where turn-on voltage is to be (partially) cancelled: connect to lower voltage and watch for latch-up, or tune it dynamically.

  • Praman Kumar added an answer in Consumption:
    What is the impact of reduction in water requirement on development ?

    If we reduce the consumption of portable water then what is the impact on development.

    Praman Kumar

     Hello Avinash

    I think you are asking about potable water meant safe for drinking purpose.

    from an individual point of view no body wants to stress their body physically and mentally by consuming less water. 

    and no organisation or institution asks any community or an individual  to reduce consumption.

    yes if potable water can also be understood as domestic water supplied by a local body - that case if community or a town has reduced its consumption - the efficient ways they subject it for domestic purpose - may have a significant impact - like the town expenditure will be reduced for every unit of water treatment before supply and every unit of waste water treated before released. overall tax burden on citizens will reduce. but such consumption reduction is possible by increased awareness in water management at citizen level - this awareness instigates need for innovative technology in the market - that consume less water with same or better output. so technology enhancement may be expected.

    Also the local region saves its thermal resources (if they are source of electricity) and reduces corresponding pollutants. 

    This reduction in water consumption may also meet the irrigation deficits in the water source areas further may enhance the local regions agricultural production. If that saved water is diverted to the small and marginal farmers then that would be an inclusive development.

  • Chhuon Sopheavy asked a question in Pharmacognosy:
    What is the importance of pharmacognosy as a branch of pharmacy?

    Please try to explain the answer to this question. Thanks

  • Romer Castillo added an answer in Academic Writing:
    How to improve in academic writing?

    Dear RG colleagues, I thank you in advance any suggestions to improve in academic writing.

    Do you also find difficult to write about technical & scientific issues?

    Do you believe that the practice of academic writing is always welcomed to express ideas and concepts in technical & scientific papers correctly, concisely and clearly?

    Romer Castillo

    Academic writing can be improved by constant reading, writing and re-writing. The research and academic community always welcome ideas and concepts in all disciplines that are put into writings and our profession tells us that such writings should be correct, concise and clear.

  • Zaidi Embong added an answer in Hydroxylation:
    Did inhibitor that contains with hydroxyl component can contribute as anti corrosion coating on the metal surface?

    Corrosion science, oxide coating

    Zaidi Embong

     Thank you Prof Dr Rana..