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  • Sally Irwin asked a question in ADD:
    Looking for answers about quantifying Genomic Bacterial DNA using Qubit

    The Qubit techs told me that there are problems due to supercoiled DNA (more common in Circular chromosomes like Bacteria) and the dye used in Qubit readings attaching to the DNA is a consistent manner. Has anyone had this problem and if so how did you get around it?  I have thought about these possible solutions and wonder if anyone else is doing this?

    1. Denature DNA to uncoil and then add dye - but not sure how long after denature to add dye or if dye might interfere with DNA strands coming back together?

    2. Nick DNA (too much work)

    3. Using a Bacterial DNA standard that I guess we assume has some supercoiled copies?

  • Derui Liu asked a question in Kymography:
    Anyone could show me how to track particle movement trajectory using ImageJ? If there is a simplified Manual, would you please share with me?

    I recently collected some data in terms of a plasma membrane located protein complex movement, and I try to find a way to kymography there movement and also their trajectory and veilocity. Could anyone help me with it?

  • Khairun Nisaa asked a question in Lysis Buffer:
    How should I select the pH of the lysis buffer to study the expression of interferon gamma based on its isoelectric point (pI)?

    I am trying to express interferon gamma in E. coli system. I used the lysis buffer with 200mM NaCl,5% SDS,1mM DTT, 0.25mg/ml Lysozyme, 50mM Tris, pH 6.8 and also pH 8. Along with this buffer I did sonicate my samples. I assume that the problem could be in selecting the proper pH of the lysis buffer.

    Induction protocols were general, such as 0.5mM IPTG, tried for 37C-4hrs, 37C-6hrs, and 20C-12hrs.   

    I would appreciate if anyone could guess where the problem is. 

  • Laura Fuentes added an answer in Indigenous Studies:
    Any suggestions on studies about aboriginal resilience?

    I would like to know if exist any study trying to explain the resilient process inside to the first nation. For be more exact in front of climate change and role perspective.

    Laura Fuentes

     Thank you so much!!

  • Rachel Messer added an answer in Longitudinal Studies:
    Does anyone knows studies / reviews about methods to reduce attrition or drop-out in longitudinal studies ?

    Does anyone knows studies / reviews about methods to reduce attrition or drop-out in longitudinal studies ?

    Rachel Messer
    1. Capaldi & Patterson (1987). An approach to the problem of recruitment and retention rates for longitudinal research.
    2. Book edited by Magnusson & Bergman (1990/1993). Data Quality in Longitudinal Research.
    3. Young et al. (2006). Attrition in longitudinal studies: Who do you lose?
  • Timothy McTighe added an answer in Hip:
    A case of 17year old fracture dislocation with OA hip

    34 year male,history of closed fracture dislocation left hip 17 years back. now presented with pain left hip last 6 months ,limping since 15 years

    on examination
    left hip 30 degree FFD, further flexion upto 50
    20 degree adduction deformity
    rotations painful just jog of movt present

    measurements left side 9 cm apparent shortening
    4 cm true shortening ,which is supra trochanteric
    these are the x rays n CT scan
    2nd x ray is taken after squarring pelvis

    plz discuss regarding the management options

    Timothy McTighe

    A very interesting and challenging case. I would agree with most comments about THA assuming no infection. As Dr. Long has stated the protrusio is a significant problem. One should be as prepared as possible. I would suggest scans and having a model made prior to surgery for evaluation. You certainly do not want to be surprised during the case. Possible acetabular custom implants might make this reconstruction easier. Newer technology and 3_D printing are helpful. I would also have deep profile shells (+6mm) and lateral inserts along with Dual-mobility style available.

    I also agree with Dr. Long on the use of modularity on the femoral side. Most of my experience is in the S-Rom Modular Stem which has stood the test of time and offers great flexibility in treating femoral offset and femoral version problems. However today there are a number of very good modular revision stems available. I have attached a couple of references.

    • [Show abstract] [Hide abstract]
      ABSTRACT: Thirty-eight oblong bilobed noncustom uncemented, porous-coated titanium acetabular components were used to reconstruct failed hip arthroplasties with large superior segmental acetabular bone deficiencies. No structural bone grafts were used. All patients were followed up for 2 to 5 years (mean, 3 years) after the operation. One patient (whose socket rested primarily on a structural bone graft from a previous procedure) had revision surgery for acetabular loosening. No other patients have had revision surgery or had another ipsilateral hip operation. At latest followup, 35 patients had no or mild pain and two patients had moderate pain. Two implants migrated more than 2 mm in the first year, then stabilized. On the latest radiographs, two implants had bead shedding, but there was no measurable migration or change in position. For selected patients with large superolateral acetabular bone deficiencies, this implant facilitated a complex reconstruction, provided good clinical results, and showed satisfactory stability at early to midterm followup in most patients.
      Clinical Orthopaedics and Related Research 03/2000; 371(371):154-60. DOI:10.1097/00003086-200002000-00019

    + 5 more attachments

  • Stefan Kurtenbach asked a question in Exosomes:
    Optimal exosome RNA library prep?

    I am a little confused on what to focus on. miRNAs are the most important, but there are longer RNAs in exosomes too... is there a way to sequence both at the same time? Or would it be better to do that separately? Why?

  • Joachim Breternitz added an answer in XRD Analysis:
    How accurate is Quantitative analysis using High score Software?

    Dear Scholars,

    I have calculated amount of two phases present using X'Pert High score software. However, I am not sure how much accurate my results are? Though the results are fairly matching with the observed XRD patterns. Can anybody comment on the accuracy by which the software calculate the percentage of phases. Is that data enough accurate to publish?

    Thanking you


  • Kenneth M Towe added an answer in Geophysics:
    What is the cause of this warming?

    In Sept. 2015, Ukrainian Central Geophysical Observatory  fixed just three temperature records in Kyiv.

    1)            Maximum temperature+35,7°C  was in Sept. 2.  This day was the warmest September since 1881.

    2)            Also on this day on 6,5°C was exceeded and pre-historical significance of the average daily temperature, which was fixed in 1938. The average temperature reached +29.1°C.

    3)            In addition, 3 September in Kiev was fixed very warm night of 1881 to that date. Night temperature is not dropped below + 20,6 ° C and thus on exceeding 3,1°C prior to the historical significance of this day in 1899.

    P.S. Most water wells disappeared. This has not been a long time !!!

  • Seyede Faeze Alavi asked a question in Proteoglycans:
    Does the positive ions in cartilage have negative effect on its compression load?

    We know that one of the effective things on compression load in cartilage is due to the repulsion of negative ions which are on the Proteoglycans, but on the other hand the cartilage is inactive due to the positive ions.

    Does the positive ions cause any disorders on this work of Proteoglycans? How?

  • Kornel Mikołajczyk added an answer in Muscle Fatigue:
    Does anybody have a method for measuring momentary muscle fatigue/muscle failure with eccentric muscle actions?

    I am looking for a method to measure momentary muscular fatigue with pure eccentric muscle actions.

    I am curious if anybody has a validated method for monitoring this?

    Kornel Mikołajczyk


    Tremor measurement can be a method of assessing muscle fatigue. Please ask my peer from Józef Pilsudski University of Physical Education, he made quite a lot research about it. You can find him on Research Gate: Jan Gajewski.

    All good to you,


  • Mohamed A. A. Mahdy added an answer in ImageJ:
    How can I plugin cell counter image J into image J?

    Can someone provide the link that explaining plugin step by step?

    Mohamed A. A. Mahdy

    Hello Friedrich, thanks for the links 

    I have question regarding the paper about automatic cell counting. Is it fit only for cell culture or can be used for paraffin sections?

  • Amanda Fitz asked a question in Bubble:
    Flouromount G lets in air as it dries, any solutions?

    For preparing IHC slides of rat brain sections, we mount with Fluoromount G, but it is common knowledge in the lab that over time it lets in air bubbles. Does anyone have any tricks to prevent or stop this? 

  • Mario Humberto Guzmán added an answer in Heterogeneous Catalysis:
    How to control the selectivity of a heterogenous catalyst?

    Is there any specific method which can control the selectivity of heterogenous catalyst?

    Mario Humberto Guzmán

    As far as i know an efficient way to determine the relevant parameters for selectivity relies mainly on the reaction mechanism, even so the textural properties may affect the transports phenomena, there is a intrinsic mechanism determined by the chemical interaction between reactives, catalyst and products. Based on this, in order to control selectivity for a catalyst, we have to improve the stabilization of intermediaries prefferently for the desired reaction route, and stablish an equilibrium between the intereaction Catalyst-reactive, catalyst-intermediary, catalyst-product, catalyst sub-products.

    I know i'm quoting just a few aspects but those are the ones I think are chemically relevant.

  • Baleni Khuthala asked a question in Foundations:
    The effects of using home language in all subjects in the foundation phase

    I would like some assistance in my research

  • Gábor Orgován asked a question in Spectrometers:
    Does anyone know the approximate price of a 900 MHz NMR spectrometer?

    I could not find any data about it.

  • Andrew David Lyle Nelson added an answer in Recombinant Protein Expression:
    Has anyone a protocol for the transformation of moss (physcomitrella patens) by an agrobacterium system?

    I am looking for protocol in transformation of moss (physcomitrella patens) for recombinant protein expression. Please guide me here. Thank in advance.

    Andrew David Lyle Nelson

    Hi Peyman,

    If transient expression is your only option, and you need to do it in physco, then transforming protoplasts and then collecting protein after a few hours is probably your best bet.

  • Sheeraz Ali added an answer in Discourse Analysis:
    How do I teach text and critical discourse in an EFL academic context?

    Dear All,

    I have viewed articles, books, and research papers on crtical discourse analysis. This is an interesting area of language teaching but how to teach critical discourse is somewhat practical. Therefore, researchers are requested to send Teaching activities for the practice teaching critical discourse. 

    Sheeraz Ali

    Dear Arif Jawaid and Georgette Nicolas Jabbour,

    Thanks for your valuable inputs. I am here more concerned with practical implications showing or suggesting activities

    The one is suggested by Mr. Jawaid that I usually practice in my class.


    Sheeraz Ali. 

  • K. Kassner added an answer in General Relativity:
    Does the bending of light describe the curvature of spacetime or the curvature of space relative to photons?

    The bending of light is happening according to general relativity because light follows the curvature of spacetime. This is what the standard text books of GR said. If we look to the problem from photons frame, what the photons encounter in their path in different gravitational potential that lead them to bend? Do they follow the space time curvature or space curvature?

    K. Kassner

    Light does not follow three-space geodesics. It follows null geodesics of spacetime.

    Even light needs time to go from A to B. So it cannot be restricted to three-space.

  • Khandoker Mahmudur Rahman added an answer in Retrieval:
    What are the various ways to store and retrieve survey data for research work?

    It is required to know the ways by which data can be organized to ease of further retrieval and analysis.

    Khandoker Mahmudur Rahman

    Adding to Charles' answer, the advantage of saving as SPSS data file (sav format) is that you can easily convert it to Excel or CSV format that may help you in further analysis through other tools like using SEM, Excel macros like moderation and mediation and so on. SPSS data file is relatively flexible to convert for using in other programs when needed. And, always back up your data! Free cloud storage like google drive, onebox or skydrive could be some of the options.

  • Jernej Polajnar added an answer in Applied Entomology:
    Are there any studies out there on brightness suppressing insect activity on a daily scale?

    We found in our recent study (in prep.) an indication that the daylight's brightness suppresses activity of a nocturnal/crepuscular insect, not any other environmental factor. In other words, the period of inactivity matches exactly the peak of brightness, while peaks of temperature/humidity and wind speed don't match as nicely.

    Are there any existing studies that we can cite to support this assertion? It's not central to our research question, but would be useful to elaborate. The only references I could find deal with seasonal patterns of activity entrained by daylight duration on longer time scales. But what about diel patterns of activity? Any pointer would be much appreciated.

    Jernej Polajnar

    Dear Dr. Mushtaq, I am interested in your project and I can probably give you some pointers if you send me the details, but it is probably best to move this discussion to private mail. Please contact me through the ResearchGate messaging and I will give you my work e-mail address.

  • Pär L Pettersson added an answer in S2 Cells:
    Using S2 cells for tetramer induction using CuSO4, protein yield has been low, is it possible the stock CuSO4 (more than 2 yrs old) has gone bad?

    Making tetramer using S2 cells

    Induction is with copper sulfate 

    Protein yield should be higher than what it currently is according to protocols and other lab members who have made it previously

    Using previously made stock CuSO4 that has been on the shelf for a while

    Determined that protein is not being lost in the wash steps of purification.

    Pär L Pettersson

    Are you eluting the Ni-NTA with imidazole or histidine?
    You can strip the Nickel from the column with EDTA and see if the protein comes out with it (if is in fact there from the beginning at all, and given that the "unwanted" binding is caused by the Ni-protein interaction). Too low ionic strength may cause "unwanted"-nonspecific binding. How much salt (NaCl or KCl) do you have in the sample?

    There is no EDTA in your samples or buffers, right? Because that will strip the Ni and your protein will go straight through.

    Do you have a method to quantitate your protein in the harvest (before purification) as well after purification, so you can do a balance sheet and compare how much you actually put in, with how much you get out?

  • Abdulelah Ahmed Thabet added an answer in Herbal Medicine:
    How to choose solvent for soxhlet extration?
    In the solvent extraction solvents like methanol, ethanol etc. are being used, but on what basis are these solvents being used?
    Abdulelah Ahmed Thabet

    Dear all
    I need your help?
    I will extract polyphenols from a plant sample by soxhlet with methanol .
    What is the best protocol for extract a plant sample by soxhlet with methanol?
    could you suggest the procedure,time required, temperature, weight of the sample and the volume of the solvent ( methanol)?

    Thank you in advance

  • Gina Dembinski added an answer in Geneious:
    Which is better Genemapper or Geneious?

    I have used genemapper to analyze data from my previous lab work. I have the option of using geneious for my recent SSR genotyping. Which gives a better result? Should I stick to genemapper or should I switch to geneious? Thank you

    Gina Dembinski

    Hi Suzzy,

    I agree with José, GeneMarker from SoftGenetics is a great software tool.  It is more user friendly, we have used it in our lab as the primary software to analyze custom SNP data, AFLP data, and microsatellites.

    Good luck,

    Gina Dembinski

  • Mary Vidhya asked a question in Digital Watermarking:
    Increasing data capacity in image watermarking means?

    Any ideas in how to increase data capacity in digital watermarking

  • Michael jeremy Shapiro added an answer in Protein Solubility:
    How do i test if a protein is soluble or insoluble on a sds page gel?

    the simplest way is to lyse the cells, spin down hard,  takeout supernatant in other tube, then how much adding 5x sds buffer to resuspend the pellet ??! (in order to make the loadings comparable).

    Michael jeremy Shapiro

    Perhaps you are just trying to determine how well your protein is solubilized by your lysis buffer?  In this case, you could resuspend the pellet in the same volume of lysis buffer that you used for the cells, then add the same volume of 5x SDS buffer.  If you then load the same volumes of the supernatant and pellet, you will get an idea of the distribution of your protein.  However, if you want to make quantitative conclusions about the distribution of your protein for a publication, then you definitely need to control for total protein content as Hediye suggested or formulate another control (this really depends on the goal of your experiment).  Note that when you add the 5x sample buffer to the insoluble material, it may become very viscous.  In this case, you can shear it by passing through a 28g needle or use sonication.  Good luck.

  • Vivek Negi asked a question in Source Apportionment:
    I have 14 data sets for 5 location in an area in terms of elemental profiles, then what possible source apportionment method can be used effectively?

    What model to be used given 14 data sets are available for receptor sites? (given source profiles are available and major sources are known) Will CMB work with only 14 data sets of only elemental concentration??

    Any other alternative to find re-suspended dust and combustion sources impact quantitatively??

  • Maranda Marvin added an answer in Child Behavior:
    What data analysis strategy should I use when measuring the relationship of one predictor variable and four outcome variables?

    Hi!  I am studying the cognitive distortions of mothers (IV-predictor) and how they relate to these four DV-outcome variables: 1) maternal perceptions of child behaviors, 2) competence in implementing early intervention strategies, 3) stress levels, and 4) depression levels.

    The main purpose of my study is gaining an understanding of how parent-specific cognitive distortions relate or are associated to the outcome levels of these four dependent variables.  All variables will measured on test measures specific to the construct (values).

    Maranda Marvin

    Thank you all for the solid direction and encouragement!