ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.
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- Do you agree with Stephen Hawking's recent conclusion that black holes don't exist? Black holes don't exist. I published this many years ago. Cantor's Universe doesn't allow the concept. Stephen Hawking now came up with the same conclusion. Read: http://www.spektrum.de/news/es-gibt-keine-schwarzen-loecher/1222059 In my opinion he is right this time. What is your opinion? Was he right then or is he correct now?
Sorry for the second question, but how does this mostly philosophical argument relates to the existence of black holes?Following
- Jacqueline Maisonnave asked a question in Application of MSC in veterinary medicineArthritis treatment with Allogeneic MSC
Chronic or acute arthritis treatment with allogeneic MSC is it successful?Following
- What are the proper Human Resource practices to ensure Job Satisfaction of the employees of commercial banks?
To Know the proper HR practices.
Thank you so much sir (Kamal Eddin Bani-Hani).Following
- How much does it matter to ligate coding sequences with upstream regions (including promoters, etc) without scar?
How much does it matter to ligate coding sequences with upstream regions (including promoters, etc) without scar?
I'm always very cautious about that, trying not be bring restriction sites between the coding sequence and the promoter region (from -1 site to the upstream sequence) when ligating them. Does it matter so much?
I know that the RBS in bacteria are very important and conserved. Many experiments does not seem to care about it and use restriction assembly, why?
These days I've been working with a yeast (eukaryotic). I haven't checked much, but also know some reports about the importance of the -3 site on efficient expression. Still, most people use restriction assembly. I'm in doubt that using that, the translation efficiency will be affected. The scanning model of eukaryotic translation doesn't explain why translation initiation is affected by adjacent regions of AUG.
More is to be revealed by structural biologists about initiation codon recognition, but now from the occurrence of consensus sequence and results of mutational experiments, I assume the sequence context is important. In fact, the promoter region (just upstream of the ATG site) displayed high similarity with the S.cerevisiae consensus sequence near the ATG site, though the promoter is from another yeast.Following
- Are there methods for alleviating purity concerns (other than hand washing)? I'm working on a research project that examines different types of judgments from social conservatives and social liberals. In one study I show that priming liberals with purity concerns make their judgments look more like conservatives' judgments. In a follow up, I want to test if the converse is true: can tamping down purity concerns make conservatives' judgments look more like liberals' judgments? Thanks for the help!
Interesting idea. If you look for other purity concerns, why not having a look at symptoms of Obsessive-compulsive disorder (OCD), especially the washing part? http://www.ocdtypes.com/washing-ocd.php
So maybe too much purity leads to more liberal views in conservatives? Alternatively you could prime conservatives with examples of injustice, which could either increase their justice or reduce their purity - or both. Especially if the latter happens, let me know.
- Agarose gel problem with miRNAs
I did a gel electrophoresis with my SYBR Green qPCR products (starting material is miRNAs) on agarose gel. First I tried 4% agarose gel with TBE buffer, but I wasn't able to observe anything on the gel. In addition, the blue shade of the loading dye on the gel was disappeared during the electrophoresis after some point. Then, I tried to decrease the agarose concentration and prepared 2.5% agarose gel. The same thing happened. No visible bands. I do not observe anything even for the DNA ladder. (I did not forget to add EtBr). Any recommendations?Following
- What is the fundamental difference between a workflow and a business process in the context of process (or workflow) automation? It is not clear to me how to distinguish them. e.g. When should I talk about a workflow model vs. a process model?
Hi, I am doing some research on the field of Business Process Automation and when searching for clarifications on the differences of workflows andI have found this view which is quite simple: "When describing a workflow, which is an executable process"(HOFESTEDE, 2009).
If we take into consideration that:
1. part of the BPM life-cycle is Business Process Modeling and that it can be done in different levels of abstraction.
2. When we model the business process in the most detailed level (execution level), then we have a workflow.
3. The execution means ”precise business process descriptions are used to guide the performance of business activities”(HOSTEDE,2009)
As brought to us by HOSTEDE(2009):
“as a consequence of the explicit representation of tasks and their
chronological dependencies, as well as the involvement of resources in
the execution of these tasks, it is easier to adapt business processes in
order to react in a timely manner to environmental changes, for example,
market fluctuations or legislative adaptations.”
“ Monitoring capabilities provide scope for rapid detection of problems
and subsequent escalation, while post-execution log analysis (i.e.,
process mining) can provide a solid basis for process improvement.”
A workflow will give us(HOSTEDE, 2009) :
“- the individual activities (or tasks) and their execution order,
- data that is to be entered and passed on,
- and the way resources are involved.”
This logic corroborates partially with Hans-Georg Fill when he says: "worflows are technical realizations of business processes". The logic that workflows represents a business process sustains, the only difference is that we add all the elements of interaction in a business process.
By definition we can say that a workflow is just a sequence of activities performed to produce an output.
When were are talking about Business Process we can say that it a sequence of activities performed to produce value.
This differ from Saleem Malik's view simply because when we are talking about workflow, as the name suggests, we are not talking about just flow, we are also talking abut "Work". Which means not only transfers, but transformations in a process. Therefor it can be characterized as a process by definition.
So when we are talking about Business Process and Workflow we are talking about processes. Following this logic when I say Business is when I see a process under a value creation point of view and when I say workflow is when I am talking about a process in its execution level with focus on the output of this process.
We could say that the workflow is how a Business Process gets standardized. Any business process only gets standarized when we have modeled it to its execution level.
This view is in alignment with Adrian Egli's conclusions: "if you like to understand a process in details such for manufacture, software development, ". However I would not not separate a Business Process from a Workflow. Because as pointed out by all, a "Workflow is just a Business Process in detail" (execution level).
Hans-Georg Fill : "Workflows are usually seen as technical realizations of business processes.". Attention to the word "realization", meaning "brought to reality", meaning "step-by-step" = Execution Level.
Muhammad Riaz: " Workflow is used to automate..." And you can only automate if you capture all the relevant elements and interaction on an execution level to give the order on what and how to perform to the Information system.
Adrian Egli: "if you like to understand a process in details ". Here details follow the logic when the author presented: "what you need todo, step-by-step".
Pedro Sobreiro: "it is also possible to make the decomposition of business processes, e.g. from high level and intrinsically related to value chain (or should be) until work level (human or machine)"
So by taking all the definitions provided by the researchers on this media and relating the ideas by them presented to the fundamental idea stated by HOSTEDE(2009) "a workflow, which is an executable process" we have the a Workflow is a level to which a Business Process can be modeled.
From now on I will call a Business Process in its Execution Level as a Workflow.
(Workflow: is a representation of a Business Process in its execution level)
Modern Business Process Automation: YAWL and its Support Environment Hardcover – November 30, 2009
by Arthur H. M. ter Hofstede (Editor), Wil van der Aalst (Editor), Michael Adams (Editor), Nick Russell (Editor)Following
- Reliability Statistics: Where did I go wrong? Help dear colleagues....
My Cronbach Alpha stated -0.656. The note below says: The value is negative due to a negative average covariance among items. This violates reliability model assumptions. You may want to check item codings.
What does this mean?
I recommened to follow the links given by our friends Costas, Abedallah, and BehrouzFollowing
- How to resolve two almost overlapped peaks in Metabolites 1H NMR apart from pure shift experiments.
Almost completely overlapped peaks with similar splitting pattern.
I am just wondering do you need just resolve the peaks (measure chemical shift and coupling) or you have to quantify both of them also?Following
- How does a commercial bank can gain competitive advantage from their rivals?
Need to know the procedures of gaining competitive advantage of a commercial banks.
By recruiting more customers through incentives and rewardsFollowing
- What do I have have to do to get a good SDS PAGE of glomalin?
I tried to make the SDS PAGE following the protocol of this article, and I have not gotten down proteins. Could you help me and give me some advice. Thank you
Hi Carolina, Even though I dont know exactly what your problem is, I would try these 1- make sure you load enough protein, 2- check the current and voltage of the gel electrophoresis apparatus, and 3- mixing the protein with appropriate SDS sample buffer and boil it for 4-5 min. I hope that would help. Good luckFollowing
- What were the causes of fish kills in your lakes, rivers, coastal waters and oceans? Fish kills can be defined as any sudden and unexpected mass mortality of wild or cultured fish over a short period of time. It could be due to pollution or contamination of waters or a combination of natural and human induced stresses in the environment. Climate change (rise of temperature) and projected increase in the frequency of algal blooms may also increase fish kills. Fish kills can occur due to a number of reasons including the following: abrupt change of temperatures (winter fish kills/summer fish kills), accidental spills; acid mine drainage (AMD), acid sulfate soils (wetlands and floodplains), algal blooms (cyanobacteria, dinoflagellates), ammonia (NH3) toxicity, anoxia, black water events, bush fire ash, crowding, climate change (rise of temperature), cold water pollution, cold stress, dam operation, dissolved solids, diseases, droughts, environmental stress, eutrophication, floods, herbicides, high temperature stress, hydrogen sulphide (H2S) toxicity, hypoxia, life cycle event, low temperature stress, metals (toxic), municipal sewage, oil spills, nutrient pollution, overturn of lakes, pesticides, pH (low), parasites, power generation water discharge, red tide, salinity, spawning activities, toxins, turbidity, underwater explosions and upwelling. Fish kills are very visible events which cause considerable interest and concern to the public. Fish kills could be an indicator of environmental stress, a declining of aquatic ecosystems health or water quality problems or water pollution or contamination of water etc. Question: What were the causes of fish kills in your lakes, rivers, coastal waters and oceans?
Recently, I hear that many tons of fish in Nile river kills due to waste water discharge and also high concentration of ammonia in river.Following
- AOA, Dr. Mazhar, I would like to have a copy of the full text of this article.
Also, I am curious to know how the thickness of an individual film was monitored and controlled?Following
- What is a interpretativerserch paper
I am not familiar with this kind of paper work, i am about to write one however, i need guidanceFollowing
- I wanna some traning to enhence performance of football player Following
- Why would the amygdala be more active during a congruent Stroop trial, compared to an incongruent?
I have conducted an fMRI study comparing recovered anorexia nervosa patients to healthy controls on an emotional stroop task. The task consists of fearful and happy faces, overlaid with either the word 'fear' or 'happy'. Thus, a given trial can either be congruent (face and word match) or incongruent (face and word mismatch). The task was to designate if the face was happy or fearful, ignoring the word. Reaction time data showed that it takes longer to respond to incongruent trials compared to congruent trials, which we expected.
However, the fMRI analysis shows that, for the control group, participants had more bilateral amygdala activation during congruent compared to incongruent trials (as shown by the extracted beta weights from left and right amygdala). I expected more amygdala activation for incongruent trials (thinking that an emotional conflict conveys more saliency). I am struggling to understand our observation.
Does anyone have any comments regarding this finding? All comments are highly appreciated!
Thanks for the comments!
1. Steve: I doubt that it has something to do with emotional memory encoding, as congruent and incongruent trials are identical in all respects, except for the fact that the word and picture may either match or mismatch.
2. Davood: I also suspected that it might have something to do with the "double fear" information. However, this is not the case. The left and right amygdala respond equally to both types of congruent trials (that is, regardless of picture and word combination). It seems that the congruency between the picture and the word in itself leads to a heightened amygdala response.
It could be that the congruency between word and picture are more "salient", leading to increased amygdala activation. Incongruent trials however, convey a conflict which are processed in other areas, such as ventral anterior cingulate.Following
- R: automatically determine sensible newdata in lm.predict
I'd like to have or write a function that automatically provides "adjusted predictions" for a linear model. For simplicity I could accept that the models must not have any interactions. With "adjusted predictions" I mean that the predictions are for the values of a specific predictor ("target predictor") are calculated with all factros at the reference levels and all metric predictors at their mean values (these cal be determined from model frame).
For this task the function has to find a sensible range for the continuous target predictors. This is relatively simple when the predictors are untransformed. However, I have not found any solution for transformed predictors.
model = lm(Y ~ A + log(B) + exp(C) + sqrt(D) + poly(E,3))
I will not consider other transformations (like I(.)). The given model is just an example. It could look different, with different variable names and transformations.
To get the adjusted predictions for a target predictor the desired function should be called like
predictions = calcPrediction(model, "C")
to the fitted values varying the values of the variable "C" while all other variables (A,B,D,E) are fixed.
My problem is to set up (automatically, given only the model passed as argument to the function) the required data.frame "newdata" for lm.predict. This data.frame must have the colnames "A","B","C"...= the names of the variables. How can I extract the variable names from the model? The names I can extract all contain the transformations/functions.
The second problem is to find an appropriate range for the target predictor. model$model contains the values used by lm, and they are transformed. To determine the range for newdata I need the untransformed values. How can the applied transformation be undone (automatically)?
I hope this was understandable...
Thans in advance for any help!
Shane, thank you for the answer. However, either I did not understand your answer you you did not get my problem...
I do have the model (as a result from lm). I do not call lm().The model I have has the parts $model and $terms (an all other gimmicks of an lm-object).
This is what I have.
Now condider, as example, I want to predict the response for the given range of a predictor (let's call it D) by a call of
newDF is a data.frame containing the values of all predictors. I want all predictors in the model (expect D) have the reference level or the mean (as in model$model). This is no problem so far. The problem is to set the values for D. When the model was Y ~ ...+D+.... then it would be simple:
get the range of the values in model$model[,"D"] and create a sequence of equally spaced values of a desired length covering this range. That's it.
But when the model was Y~...+log2(D)+... then I could still find the corresponding column in model$model, but there are the log2-values given, and in newDF I would need the values on the linear scale.The sequence of values for log2(D) can be obtained as explained above. But eventually in newDF I must give these values on the original scale (D, not log2(D)). So these values need to be back transformed (here by 2^x). I do not know how to find the inverse function automatically. I could programm a larger case-structure checking every possible function and providing then applying the corresponding inverse transformation. But this is extremely ugly and it won't work with functions that are not known (and, for instance, how would I invert poly(D,3)?).
So I want a smart work-around for this (and it would be an optional plus if it also would invert "unknown" functions. I am not sure if something like this is possible at all. I did not find anything yet. Therefore I am asking.Following
- How to clean paraffin wax off counters and equipment.
I am working with paraffin wax, and it gets everywhere when I am finished working with it. Is there any good solutions or techniques that are good at cleaning them off surfaces.Following
- What are the specific areas of interest when studying the 'form' and 'content' of contemporary ceramics products?
Art Historical analysis involving 'form' and 'content' usually generate controversies on how it should be rightly judged and graded. This is because research topics involving 'form' and 'content' are, perhaps, have multidimentional approaches that in most cases weaken the essence of the research. While 'form' represents the external features and general appearance of an art work, the 'content' is the meaningful interpretations that the researcher puts forth to match his/her projections. But this is mostly the case in fine art researches involving painting, sculpture, installation art, drawing, etc. Since most (if not all) ceramics products are supposedly utilitarian in nature, under going a study of form and content may require specific areas of concentration to arrive at a good analysis.
If the ceramic piece transmits a message, the concepts of form and content may be applied as in the study of any other work of art. If not, the relevant dichotomy would be form/function. Often all three concepts, form, content, and function, may apply. (These reflections may also be applied to the study of architecture.)Following
- What is the difference between Granite and plagiogranite rocks
Plagiogranite rocks is related with Ophiolite while granite rocks notFollowing
- Where can I find a prostate cancer dataset?
I am looking for a dataset with data gathered from African and African Caribbean men while undergoing tests for prostate cancer. In particular the dataset should have patient information such age, ethnicity, family history etc, urinary symproms, other prostate cance related symptoms and results from tests such as PSA, Gleason, DRE etc. If anyone holds such a dataset and would like to collaborate with me and the reseach group (ISRG at NTU) on a prostate cancer project to develop risk prediction models, then please contact me.
The SEOM, ESMO, ASCO and NCCN guidelines are very good summaries. The SEOM, -Spanish Society for Medical Oncology- toghether with the ICO, Catalan Institute of Oncology, e-oncologia, and the Girona University have a module based, on-line crash course in Medical Oncology, 750 hrs of credits, that contains a highly detailed Prostate Cancer Module, with very good information about individualized care according to subtle differences in tumor stage and biology.
Classic texts, as 'de Vita Principles and Practice of Oncology' do contain lots of good info. Urology societies all over the world also issue their own guidelines on Prostate cancer management. Vollmer RT has addressed many important issues in Prostate Ca. It depends on the level of complexity and how deep you want going in the subject, i.e, on your needs, my level is a bit above a last years' resident. . Hope it's useful. Regards.Following
- Is a Likert-type scale ordinal or interval data? I've heard arguments that a Likert-type scale is ordinal data. I've heard arguments that this type of data is interval data. Some believe it is quasi-ordinal-interval data. Which exactly is it?
the example you constructed is exactly what I would call a high stake situation, where formally strict treatment is indicated. So, we seem to be on the same page. Except, maybe, that in such a situation I would never rely on just three items.
However, we academic hardliners may rant about such practices, but that won't stop pragmatically oriented people from doing it. Or have you ever heard of a case where someone sued a human resource specialist because of mistreating test data?
So, what can we do about it? Constructing examples that show potential misuse or bias is one thing. But, do we have
(1) procedure to test relevant measurement properties
(2) quantification of bias that occurs in typical high stake situations (preferably expressing it as losses)
- How do I remove para amino toluene from 3,5 -bis(tolyl carbamoyl)phenyl pivalate?
I synthesised [3,5 -bis(tolyl carbamoyl)phenyl pivalate] by reaction of 5-acetoxyisophthalic acid with para amino toluene and according TLC i have an exess of Para amino toluene. Moreover, i used DMAP and DIC as a catalyst.
Well, in general we use 1M sulphuric acid or a 2M HCl to remove anilin derivatives during our workup (for example in the synthesis of quite stable imins), I would give that a try. If you think this could be to strong you could try a saturated ammoniumchloride solution to wash you organic phase. Check all your phases by TLC to be sure were to find your impuritiesFollowing
- What is the best solvent system to run crude plant extract on TLC? I am working with Verbenaceae family plants. What is the best solvent system to run crude extract on TLC?
I have used toluene: Methanol (8:1, v/v) mobile phase with 10% methanolic sulphuric acid as derivatizing reagent (366 nm) and Toluene : Hexane (9:0.5, v/v) for crude plant extracts of some verbenaceae members. Hope it works
Also the suggestions made by all these members should be taken into consideration when developing HPTLC fingerprints.Following
- Is there a good resource out there for determining correlations between dental diseases?
Basically, I am looking for resources that may help determine the likelihood that an individual would have, say, an abscess, given the fact they have severe carious lesions. Something that might give a "correlation coefficient" or something. ThanksFollowing
- Could other groups of beta-hemolytic Streptococcus, in addition to group A (Lancefield's classification), produce antistreptolysin-O?
In one of our researchs, one patient with positive throat culture for Group B Streptococcus, presented reagent ASO, in a titer of 800 U/Tood. Could other groups produce ASO? Is it an occasional finding? Or did the patient present a previous infection by Group A Streptococcus in the last six months?
PMID 1452695, Tyler SD, 1992, points that all GASt produce SLO, and no other strains or bacteria have this toxin. As a matter of curiosity in the 70's, Madrid Clinico de san Carlos Hospital, a yearly research meeting, they presented studies on the functions of different parts of Antibodies, coming from a patient suffering a Multiple Myeloma that secreted Anti Strepto Lysin O.
I had a pair of angry parents in my office because their kid had sustained ASLO titers in the region of 200, and a predecessor in the place was injecting Penicillin periodically to the boy. If I remember well, their image was that SR Penicillin had to be given until ASLO titers decreased to near zero, situation was solved by referring the case to an specialist in ENT, but the idea that treating the ASLO or treating an active infection is a confuse mix may remain.
How often should ASLO assesment be repeated, and how safe is considering that an steady ASLO titer, in the absence of acute phase markers, such as CRP, reflects a non-active, memorial condition remains dubious to me.
- Which type of connection is used in distribution transformer?
Zig-Zag connection is very useful connection, for grounding transformer, as is use ful, in blocking third harmonics and its multiple.For main municipal lavel, distribution transformer(Dz), secondary side unbalanced loading(load shering bet. phase) of distribution system, would be more convenient to taken care of. The normaly used connection for distribution transformer is Dy.Following
- Why doing Mantel test instead of a glm? What about multiple testing?
I am currently doing an analysis where I have to do multiple Mantel tests. Concerning the problem of multiple Testing I am thinking of "rolling out" the matrices to vectors and then just do a GLM. But is that a valid analysis? And if not, is there any Mantel Test framework for multiple testing?
sounds really promising. Seems like its possible to just fit dissimilarity matrices instead of vectors in the adonis model. And thanks for the hint concerning mantel tests, I will definitely have a look at that.Following
- In large organizations, often managers fail in their job, but just survive; some excel. Why so? Any research?
The chances of managerial failure in larger organizations is observed as higher than is the case in SMEs. What do you think makes the managerial function in such organizations more difficult?
Dear Debi, interesting theoretical point I must confess, and I could not agree more. Unfortunately, in practice reality is much different. I think it may be worse in SMEs since for managers. At least this is what I have experienced in my working life. Perhaps it might be too risky to generalise, it depends on a host of other things.
Overall I am thankful to you for your very keen thoughts.Following