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  • Tony Nguyen added an answer in Micromanipulation:
    Which Micromanipulator do you recommend for Pronuclear microinjection?

    I am planing to do Pronuclear Microinjection. Could you give me recommendation for Micromanipulator?

    Do I need a electronic controlled device for this purpose, or would a manual/mechanic micromanipulator be suitable?

    Thank you.

    Tony Nguyen

    Hi Mulyoto

    Thank your for your response.

    On most of the publication I have read, they used a electronic/motorised micromanipulator (Eppendorf Transferman). Do you know if a mechanical Micromanipulator can also be used for Pronuclear injection?

    And another question: Do you really nead 2 Micromanipulators? Due to our budget, I am thinking of buying only one Eppendorf Transferman for injecting, and one "Scientifica LBM-7 Manual Manipulator" for holding of the oocyte.

    What do you think?

    Best Regards


  • Tatiana Bruni asked a question in Academic Development:
    Is anyone aware of any studies on teaching general critical though and skills in Foreign Language classes at elementary level (in Higher Education)?

    In Higher Education curricula, in particular in LAS colleges, enhancing students’ critical thinking skills is one of the core goals. Usually one of the challenges teachers face is that college and university students have already (some) skills for critical thought, but in foreign language classes, in particular at beginner level, they miss the language proficiency to articulate well they thoughts.

    So often teacher have to resort to have discussions and pieces of writing in the native language or in the communication language of their class. This can sometimes be detrimental to the language acquisition process. On the other hand, if students don’t feel that they have sufficient linguistic instruments to express their ideas, they might experience frustration and feel as foreign language classes are not contributing to their academic development like other (content) courses, and they will tend to prioritize studying and working for other classes.

    I am looking for research and good practices on how to develop critical thought using the target language at low levels of proficiency, to avoid resorting (too much) to for example using English.

    Thank you in advance. Tatiana

  • David Alcantara asked a question in Animal Production:
    Can anyone suggest me where I could find some statistics on slaughterhouse waste in Europe?

    I need to know:

    - total slaughter house waste

    - % of the different animal by product (category 1, 2 and 3)

  • Manohar Sehgal added an answer in Calcium Citrate:
    How can I extract calcium citrate from an aqeueous solution containing magnesium citrate and calcium citrate ?

    Want to obtain calcium citrate precipitate 

    Manohar Sehgal

     My submission is:

    Will the presence of CaCl2  make  the  mixture solution slightly alkaline [ pH=7.2] or  acidic[ pH less than 7]?

  • Michael Alexander Kurz added an answer in Big Bang:
    Are particles created from the energy released during the Big Bang? During expansion, does the energy continuous converted into matters?

    We have learnt from the big bang cosmology that all the particles was created after the big bang explosion. My question is that whether these particles was created from the energy released due to the big bang? If yes, the energy density must be decreases during the course of expansion as it is continuously converting into masses or matters. Again if it happens so, the mass of universe must be increasing with time or expansion.

    Please some give some light on it. I'm working on a solution of Einstein's field equations and I got an expanding solution with an initial singularity. As the time increase to future, its mass and radius increases. So I need to explain the increase in mass with time.

    Michael Alexander Kurz

    Dear Newton,

    curved space-time and matter are maybe two sides of the same medal, where matter (and any other form of positive energy) is associated with an attractive force (gravitation), whereas space-time is associated with a repulsive force. In my model, the big bang is nothing else than the formation of a single Planck-particle, which can be regarded as the smallest particle of matter or as the smallest quantum of curved space-time. Every Planck-time, a new Planck-particle is created too. Please note, that the radius of a Planck-particle equals ist own Schwarzschild-radius, so that the primordial universe has a radius that equals ist event horizon and ist energy density equals the critical density. The increase in matter of one Planck-particle per Planck-time also increases the Schwarzschild-radius, so that radius and Schwarzschild-radius of the universe are always the same. This might explain, why we have now a flat universe with an energy density equalling the critical density. Please also note, that the assumed production rate of matter and space-time produces exactly the observed radius and energy-content of the nowadays universe.

    If curved space-time is a form of negative energy and creates a repulsive force, it will cause the universe to expand. In order not to corrumpate the law of energy preservation, a corresponding amount of matter has to be created too. Or from the other side of the medal: If the energy in universe increases, ist Schwarzschild-radius increases too. In order not to corrumpate the law of energy preservation...

    A quite interesting side aspect of a repulsive force caused by curved space-time will also be, that it will prevent a black hole from collapsing to a singularity! Collapsing matter and curved space-time will hold each other at an equilibrium in a sphere of the corresponding Schwarzschild-radius.

    The correlation of physical constants with the age and radius of the universe also solves another problem. If t and R are zero, these constants are not defined, which means, the zero state (the singualrity) is physically not defined and therefore not part of our universe.

    All the best


  • Belgroune Brahim added an answer in eLearning:
    Is there any data base of interaction traces?

    please, if there any one that he is working on the analysis of interaction traces (in elearning). thank you to send me data base of interaction traces to use it in my research.

    Belgroune Brahim

    Thank you

  • Paul Whybrow added an answer in Content Analysis:
    In a qualitative study, how do you content analyze response that has both positive and negative statement; that contains the "BUT" or "DEPENDS"?

    For example, on a topic of whether reward can encourage a person to share his/her knowledge, an informant said: "Yes it can. But rewards should not be exercised because it encourage people to be "subsidized" to do good things". OR

    "Depends but not always. Most crucial is the environment, peers and relationship".

    So, in the analysis, it would be easy to categorize the solid "YES" and "NO" response. But where and how the above case should go in?

    Hope anyone can share their view and knowledge on this. Thanks!

    Paul Whybrow

    I would suggest that good qualitative analysis would not try and force yes/no categories ever!  Such polarisation would be to prep data QUANT analysis! 

    I would suggest sticking with meaningful key words - eg "ENVIRONMENT" "PEERS" for example.

  • Jyotima Kanaujia added an answer in Seismic Tomography:
    What are the statistical analysis can be performed for (seismic tomography) synthetic test images regarding their resolutions?

    which type of statistical analysis can be performed on the resulting suite of some test images, yielding a quantitative measure of the portions of the image that are well-resolved?

    Jyotima Kanaujia

    Dear Michele,

    Thank you very much for detailed information on the topic.  This is very useful. Yes I have done Checkerboard test and inversion with varying selected data set, inversion multiple starting models. Now you have suggested Jack Knifing, I want to know more about it. May I request you to please provide me some relevant information about it, if possible? 



  • Dr. B Sairam added an answer in Seismic Tomography:
    How can I apply masks on tomographic images?

    I have some images from my tomographic inversion results. I want to apply a mask on the images in a manner that I can trace manually a polygon for some selected area and then mask the anomalies located outside that polygon (for example, using a transparency tool, 50-70%). I have no idea how to do it. Any help regarding this would be appreciable. 

    Dr. B Sairam

    There is option available in the Surfer software also.

  • Praveen Kumar added an answer in Schizonts:
    Does anyone have any Plasmodium synchronization tips?

    I am trying to get my plasmodium falciparum parasites synchronized to a 1hr time frame. I do a treatment of 5% sorbitol at 15hpi, then repeat at 5hpi. At 48hpi I run them through a MACs column to purify bursting schizonts, allow to grow for 1 hour and purify with sorbitol to get young rings. It seems as though my sorbitol treatments are too efficient because I still have schizonts and trophs in my culture when I should only have the young rings. Any have suggestions on how to make my window of synchronization tighter without putting stress on the parasites? Thank you in advance!

    Praveen Kumar

    Check if you can use this protocol:


  • László Lichtenstein asked a question in Carpathians:
    Does anyone know any archaeological evidence in Britain about the Sarmatians who were arrive after AD.175 from the Carpathian basin?

    Does anyone know publications, articles of this topic?

    I would like to get information about finds, artifacts in Britain who has got close connection, parallel with Sarmatian finds from the Carpathian Basin. Burial customs etc.  

  • Mohamad Ivan Fanany added an answer in Human-Computer Interaction:
    Which are the fast acceptance rate journals in which character recognition can be communicated?
    Which are the fast acceptance rate journals in which character recognition can be communicated?
    Mohamad Ivan Fanany

    Dear Sreeraj,

    Recently, I did a little research on Computer Science (including Computer Vision, Pattern Recognition or Image Processing) Journals List, Review Speed, Impact Factors, and Open Access Fee from Elsevier, Springer, and Hindawi. Please find them at the attached links.

    Hope this would help.


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  • İhsan Basaran asked a question in Acetals:
    Has anyone ever achieved a click reaction in acetic acid or acetic acid-organic solvent mixture ?

    Altough I already know that click reaction is not pH sensitive still wonder if any reasearch with click reaction in acetic acid solution was made or not.

  • Theodore Kapellos asked a question in Epigenetics:
    Does anyone know of a reliable promoter epigenetic control prediction software?

    I would like to have an idea of the epigenetic control potential of my gene of interest in inflammatory conditions in macrophages. I was wondering whether there is any prediction software available for use online.

  • Khalid Alshail asked a question in Seawater Desalination:
    I'm looking for a program to compare the cost of desalination (MSF-MED-RO)?

    I'm looking for a program that can compare the cost per cubic meter per day for the main different seawater desalination technologies?

  • René Schlegelmilch added an answer in Working Memory:
    Is anyone familiar with the literature review of working memory ?

    Psychological research on modality differences suggests that
    verbal material presented aurally and visually is processed in
    different parts of the memory system.

    Do these different parts of the memory system fall under the phonological loop, suggested by Baddeley ? Because the Visuo-Spatial Sketchpad is used for non-verbal input, Am I right ?

    René Schlegelmilch

    Hi Sami,

    they do not fall under the "phonological loop", because it is a different theory, than the Cognitive Theory of Multi Media Learning (Moreno, Mayer), where the modality effect is investigated.The phonological loop however is just one component in the MultiComponent Model by Baddeley and Hitch. However, a question like: "Does the phonological loop only provide verbal input and storage OR is it ALSO the place of a modality specific verbal processing" is valid, but not new. See  below:

     I attached two papers from my former Professor Ralf Rummer. Who was investigating the question, why there is a modality effect. He takes the question you make into account. In these papers you will also find an overview which theory makes assumptions on how this effect might occur. As well as alternative reasons. At his page you will find more contributions regarding the question you ask.

    (There is also a textbook, which will help you differentiating between diffrent accounts: "Models of Working Memory" by Miyake & Schah.)

    Best, René

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  • Matilde R Chacon added an answer in microRNA:
    Anyone know how to normalize miRNA expression levels from Culture Media?

    We would like to measure two selected miRNA expression levels in cell culture media of polarized THP_1.  Some people use an spike in mirna, but I wonder if this is an OK procedure.

    Matilde R Chacon

    Thanks a lot Timothy!!

  • Hazim Hashim Tahir added an answer in Language:
    What do you say about "Music is the Food of the Soul? how would the music effect our life?

    it has always been said that music is the language of feeling and of passion, as words are the language of reason. Now the nature of man consists in this, that his will strives, is satisfied and strives anew, and so on forever. Indeed, his happiness and well-being consist simply in the quick transition from wish to satisfaction, and from satisfaction to a new wish.

    Many things we love the most aren’t that good for us. However, music is one definite exception to that rule. If we ate music, it would taste like chocolate cake, but it’s actually nutritious—food for the soul, and the mind. No one would turn down a slice of chocolate cake that made you healthier (a marketing executive’s dream!), and not many people can say that they don’t enjoy music. Convincing your child to play music instead of just listening to it may seem as impossible as getting them to eat their broccoli, but the payoff is inarguably sweet.

    Hazim Hashim Tahir

    Dear Colleagues,

    Good Day,

    I would like to bring an interesting article related to the oldest musical instrument that it has been mentioned so many times in the holy "Bible".

    Ancient Harp from Ur 

    The earliest harps and lyres were found in Sumer, 3500 BC, and several harps were found in burial pits and royal tombs in Ur. The oldest depictions of harps without a forepillar can be seen in the wall paintings of ancient Egyptian tombs dating from as early as 3000 B.C. which show an instrument that closely resembles the hunter's bow, without the pillar that we find in modern harps.

    In ancient times the harp was played with the hand while walking. It had multiple strings and sometimes a sounding board, as with this harp excavated in the ruins of ancient Ur, where Abraham originally lived. 
    Notice this harp has 11 strings with a nicely ornamented sounding board with a ram's head at the end. 

    Isaiah 23:16 - Take an harp, go about the city, thou harlot that hast been forgotten; make sweet melody, sing many songs, that thou mayest be remembered.

    Psalms 147:7 - Sing unto the LORD with thanksgiving; sing praise upon the harp unto our God:

    Genesis 4:21 - And his brother's name [was] Jubal: he was the father of all such as handle the harp and organ.

    Psalms 98:5 - Sing unto the LORD with the harp; with the harp, and the voice of a psalm.please, see these lovely pictures of harps:

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  • Kavita Singh asked a question in Creatine:
    Has anyone ever found a discrepency in the level of cholines observed through in vivo 1H-MRS and in vitro 1H-MRS of rat brain in any pathology?

    The choline levels obtained by in vivo MRS are ratios with respect to creatine, however when i compared absolute, then too this discrepancy was observed. The in vitro MRS data shows reduced choline and in vivo shows increase in choline. What could be the probable reason for this?

  • Alex Russell added an answer in Data Aggregation:
    How do I proceed with SPSS as it cannot compute Spearman's Rank because one of the variables is constant?

    Hello all,

    I want to use Spearman's Rank Correlation to to measure association between two constructs - Culture and Ethics. I have coded  the Likert Scale data and aggregated the responses from the several questions in the questionnaires into two sets (Culture and Ethics) using the median values of responses from each question. However, in one of the Construct of 7 questions the median values are the same number (2). Now SPSS will not perform Spearman's Rank Correlation for the two Construct because 'one of the variable is constant'. Am I right to have used median values? What did I do wrong? How do I remedy this?

    Many thanks! 

  • Jagruti Meshram asked a question in Biopolymers:
    What are the advantages of ester for wound dressings?

    Biopolymers having COOH and OH undergo esterification reaction observed in most of the biopolymers used for wound dressing. If ester is not formed and only mixture is formed between the 2 polymers. whether it will affect the property of wound dressing.    

  • Emilia Marsellou added an answer in EViews:
    How do I estimate a cointegration relation with exogenous varibales?


    I am estimating cointegration relationship among variables. However, one of the variables is exogenous whilst the remaining variables are all endogenous. I wanted to ask if anyone can advice me on how to estimate this cointegration relationship in Eviews or using any other software.

    Thank you. 

    Emilia Marsellou

    Hi, in Eviews there is a space for exogenous variables (not c or t, but dummies etc) in the Johansen cointegration test. However, critical values may not be valid. 

  • Béatrice Marianne Ewalds-Kvist added an answer in Likert Scale:
    What study design was used in this study?

    The question asks 1) What type of design did the current study use. 

    I first thought it would be qualitative methods as there is a questionaire aimed at 15 year olds who drop out of sports clubs after school. The author wants to measure enjoyment and low competences, as independent variables and the dependent variable being there age, 15.

    But within the questionnaire there is a likert scale aimed from 1-7; 1 being disagree completely, and 7 being I agree completely. 

    The Hypothesis: There would be a significant difference between scores on Enjoyment compared to Perceived Competence.

    I've been looking at levels of data nominal, ordinal, interval and ratio but there is no clear indication of the correct test. 

    I'm currently looking at Mann Whitney test or Kruskal Wallis test. 

    Could anyone give me any suggestions?

    Béatrice Marianne Ewalds-Kvist

    Dear Paul, 

    What is the design then in this case?

  • Artur Burzynski added an answer in DNA Purification:
    Why RNase Solution is not working (Wizard Genomic DNA Purification Kit)?

    I performed bacterial DNA isolation using Wizard Genomic DNA Purification Kit, but the A260/A280 absorbance ratio is showing results above 2.10 (indicating high RNA presence). Can I perform another bath incubation at 37° C for 60 minutes to solve this problem?

  • Euan Johnstone added an answer in BCA Assay:
    What is the best method for quantifying the total protein concentration of secretome samples from prostate cancer cell line samples?

    I grew up multiple prostate cancer cell lines at multiple seeding densities and incubated them for 72 hours. After 72 hours I substituted the normal culture media for Chemically Defined Chinese Hamster Ovary media (CDCHO GIBCO) and incubated them for a further 72 hours. I then collected the CDCHO and tried to run a BCA protein determination. Unfortunately the blank as well as all the standards (using CDCHO as a diluent) gave very high readings, often bigger than my actual secretome samples. This leads me to believe that there is something in the CDCHO that is interfering with the BCA assay.

    Does anyone have any experience when using CDCHO or secretomes when calculating the total protein content? If so what method would you advise (such as Bradford or Lowry assays) and can you tell me what might be interfering with the BCA assay?

    Kind regards,


    Euan Johnstone

    Hi Everyone,

    So after being very silent for the past few weeks (I had to figure this out and give 2nd year tutorials), I have had some success.

    Thanks Maria I found an interesting modified Bradford assay that seems to have worked (Linked below)

    Thanks for the suggestion Avinash. Ideally that would be perfect but I'm also running a parallel study to identify precipitation methods which will aid MS/MS downstream so I wanted to determine the protein concentration prior to each precipitation method.

    Thanks Laura. I've taken a look at similar lists before and unfortunately makeup of the chemically defined media we bought from Gibco is kept very secretive so we actually didn't have any reference to go on to what was actually in there. That being said there is definitely something in there that interferes with the BCA assay.

    So to combat all of this I found some papers on secretome analysis alluded to the use of the Bradford assay.  I went one step further and used a modified Bradford assay (given below). I then further modified it to use the smallest amount of sample possible to reduce wastage (20ul) while keeping the Bradford concentration the same. The results were fairly promising and managed to detect the protein concentration in complex samples. We will only really know how accurate they were once I've completed the analysis on my protein precipitation experiments.

    So in conclusion it looks as if the Bradford method can work if samples are diluted and the amount of Bradford reagent is reduced and measured at two different wavelengths (as described in the paper below). I'll keep everyone updated on my progress. 

    Have a great Friday,



  • Ivo Carneiro de Sousa added an answer in Literary Theory:
    Can anyone recommend introductory material on literary theory and analysis of literary texts? It would be better if it covers various approaches.

    I need it for teaching at undergraduate level for learners. Your effort will highly be appreciated.

    Ivo Carneiro de Sousa

    Yes, Prof. Manuel Antonio is right since Peter Barry book is excellent and has plenty of pedagogic suggestions. Although my e-book copy is not particularly good, I send it to you.

  • Mario Helmis added an answer in Dentistry:
    Does somebody know how to prove/explain scientifically the antibacterial effect of copper dental cements?
    The antimicrobial activity of copper has been known for its healing properties since antiquity.
    Towards the end of the 19th century zinc phosphate dental cements with added low-water soluble copper salts at low concentration have been generally used and their effectiveness has been proved through clinical studies.
    Mario Helmis

    Try Liquid culture or agar diffusion test with species your interested in. For Liquid culture testings start with a low optical density to follow species growth.

  • Béatrice Marianne Ewalds-Kvist added an answer in Domperidone:
    What are the possible benefits of combining PPI with Domperidone?

    Are there any studies or analysis of rationale of combining these Drugs?

    Béatrice Marianne Ewalds-Kvist

    As you see it is not always a blessing!

  • Béatrice Marianne Ewalds-Kvist added an answer in Dramaturgy:
    Can anyone help me to define the main concepts of Wendy Wasserstein's dramaturgical discourse?

    Can you help me to define the main concepts in Wendy Wasserstein's dramaturgical discourse?

    Béatrice Marianne Ewalds-Kvist

    Not really I just tried to help you:)

  • Marta Załęska-Kocięcka asked a question in SCR:
    How to interpret KDIGO criteria for periprocedural AKI?

    I would like to ask you for help in interpretation of KDIGO criteria for AKI in periprocedural settings.

    I have problem with criterium: increase in Scr by at least 26.1 mg/dl within 48 hours, when applying it to periprocedural AKI. Does the increase need to appear within 48h with baseline as reference? Or may the reference be a postprocedural measurement. Below you can find examples of both scenarios:

    PATIENT1: baseline Cr: 100 mmol/l;
    postprocedural Cr: 0h: 105 mmol/l; 12h: 110 mmol/l; 24h: 140mmol/l

    PATIENT2: baseline Cr: 100 mmol/l;
    postprocedural Cr: 0h: 80 mmol/l; 12h: 110 mmol/l; 24h: 120mmol/l

    In both cases there is Scr increase over 26.1 mmol/l but in PATIENT 1 the reference is baseline and in PATIENT it is 0h.
    Do they both have periprocedural AKI according to KDIGO criteria or is it only the first one?

    Looking forward to your replies