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- 3Silicon wafer flow away or cannot get a homogenour layer?
I was trying to use silicon wafer to do a master, I never had any problems before until rencently I realized that I cannot get a homogenous layer of omnicoat and SU-8, what could be the problem? Do you think is vacuum, temperature or humidity?
The SU-8 layer is never homogenous. In fact, it is thinner in the middle and thicker towards the edges. Depending on the application, this is often a non-issue (tolerance of 3D structures). To minimize this non-uniformity, you have to center the wafer, and also make sure the deposited SU8 is as symmetrical as possible (just wait and let it become a puddle. don't spin right away).
Also, before spinning, although it may seem redundant, it is good to clean it with acetone, propyl alcohol, methanol, then water. Afterwhich, you bake at 100 degrees celsius, in order to remove excess water. This water from the environment, may cause SU8 to "slip" on your wafer.Following
- 22Is there Godel's Incompleteness Theorem in Physics like in Mathematics?
The holy grail of Physics is the Unification Theory called by Weinberg as the "Final Theory". When finally discovered, perhaps it can:
1. Unify all fundamental forces in nature.
2. Explain the Hierarchy Problem
3. Explain all Cosmological Problems
5. Gives us the right Quantum Interpretation
but can such theory derive all fundamental dimensionless constants in nature out of pure number and explain the true nature of time?
I agree with Claude Pierre Massé and some other opinions here, but they refer only to the (dominating) mainstream paradigm of so-called "positivistic science" (or "shut up and calculate"). Although this one invariably presents itself as the only possible kind of truly scientific knowledge, this is not true at all. As a matter of fact, this is the simplest possible "model" of reality (its zero-dimensional, point-like projection) with the maximum degree of deviation from the unreduced dynamics of natural structures (it is shown rigorously). The exact, intrinsically complete and totally unified description of reality is possible and has been realised (including ALL levels of reality, not only that of elementary particles), with its properly extended mathematical basis. Godel's incompleteness remains a mathematical curiosity (of usual abstract mathematics), while in the unreduced description of reality some temporary "incompleteness" can be found rather in a trivial form of yet inaccessible experimentally levels or regions of the world (while the accessible ones are described completely, without postulated "mysteries" and "dark matters", being only artifacts of the artificially reduced conventional description). All references with further details at https://sites.google.com/site/unifiedcomplexity/.Following
- 3What are the clinical implications of Acoustic Change Complex (ACC)?
I want to know about the clinical implication of ACC. Thanking You!
In my view, the so-called ACC is simply a P1-N1-P2 complex (in adults) elicited to the second stimulus (the change stimulus) in a 2-stimulus sound. ALL P1-N1-P2 responses are CAEPs to a change in an "ongoing" sound. Under more-typical situations, the ongoing sound is the background silence or noise. However, there are many studies showing P1-N1-P2 response to a frequency change or intensity change, for example, in an ongoing tone.
The "ACC" paradigm is typically one where a change is introduced in the middle of an initial stimulus. Really not so different from the above, except that the "ongoing" sound, the initial stimulus, is a transient stimulus that also elicits a P1-N1-P2.
As for clinical applicability: The presence of an "ACC" response indicates the brain has the capacity (i.e., information) to detect the changed stimulus. This does not mean it actually detects (signals) that a change has occurred. The ABSENCE of an "ACC" response is not useful clinically. Thus, the clinical usefulness of the "ACC" is currently very limited.Following
- 1Do you know technology classifications or categories?
I want to describe on a generall level how technological change impact on different technologies of an organization. I hope, there exist a kind of categorization schema for various kinds of technologies independently from any industry affiliation.
Accoding to khalil (2000), there are 6 classifications of technology namely new, old, medium, high, low, and appropriate technologies.
While there are 4 components of technology: technoware, infoware, humanware, & orgaware.
With many terminologies in MOT, levels of technology also exists interm of incremental-radical, exploitation-exploration, etc.Following
- NewHow can I experimentally measure surface charge density of ion-exchange membrane?
I wish to know the surface charge density of some commercially available ion-exchange membranes by means of a practical method in lab.
Thank you in advanceFollowing
- 1What is Yours opinion about Alternative Impact Factor?
Several journal metrics are calculated. The first metric is an alternative impact factor which is based on Google Scholar's citation count.
The journal impact factor (JIF) normally referred to is the proprietary journal impact factor from Thomson Reuters calculated based on the Web of Science (WOS) and published in the Journal Citation Reports® (JCR). We call this the JCR®JIF. DOAJ writes: "There is only one official, universally recognised impact factor that is generated by Thomson Reuters; it is a proprietary measure run by a profit making organisation. It runs against the ethics and principles of open access." This journal has no JCR®JIF, but an alternative Google-based impact factor.
This certainly sounds like an interesting idea. There has been substantial comment on ResearchGate regarding the misleading nature of the commonly used 'impact factor.' There will still be problems with interpretation, but apparently less opportunity for possible commercial misuse with a new factor such as you note here. Having the "factor" more directly linked to the author sounds useful. However, I wonder if down the road, the size of an audience might also be considered. When we write for more advanced topics, the possible number of downloads and citations is diminished. Also, I know I have a number of self-citations which probably should not count as much. But these refinements might come later. Meanwhile, I think your suggestion is excellent.
Cheers - JimFollowing
- 12How come metonymy remains a poor sister with regard to metaphor?
How come (conceptual) metonymy remains a poor sister with regard to (conceptual) metaphor?
A sign is which may or may not be arbitrary can be a referrant for many nouns as well as verbs!
- 5How temperature inside the building can be reduced while it is being ventilated by tromb wall??
I have designed a tromb wall for a single room.The outside temperature is very high thus the air coming from window has very high temperature and the person inside is feeling uncomfortable (when I check the PMV in CFD).how the air can be cooled?? give suggestions
The schematic diagram of the room looks like as it is attached here
Thanks to all, it helped a lotFollowing
- 3Anyone working in the field of AYUSH intervention in palliative care, or end of life care?
I am searching for research literature and scholars working on Indic perspectives on end of life care. Can anyone who has been working or published in this area may kindly share their experience and published work? Thank you.
Developing an innovative model of palliative care in the community in brazil
Santiago Rodríguez Corrêa, Mauro AlmeidaFollowing
- Pierre Ferreira do Prado added an answer in Artificial societies:3Can anyone point me to a mathematical/computational PROOF that the combination of two artificial societies is itself an artificial society (or not!)?
Such a proof requires, of course, precise mathematical/computational definitions of “artificial society”, “combination”, and all other more specific concepts/properties involved.
Note that such a theorem should surely make no reference to the possible use of artificial societies as models of human societies.
For the established idea of an "artificial society" see, for example, the on-line journal JASSS: Journal of Artificial Societies and Social SimulationFollowing
- NewAre there outcome measures or research studies for physical therapy protocols in inpatient rehab specifically bariatric stroke patients?
Designing an inservice for an inpatient rehab that recently had a bariatric patient with a left sided stroke. I want to see if there are any established protocols in place or research studies that back up specific interventions that can be utilized in this setting.Following
- 12If you are analyzing a narrative data, what and how do you analyze it? What are the elements of the narrative that you will be looking at?
How would you interpret the narrative data if your participants or the text involve people from different background. What are the sets of measurements that you will be looking at?
It is just for class paper but I may develop a research study out of it. thanks for your interest in my paper.Following
- 19How can I find clear sky days in a year using meteorological measurements, primarily using GHI (Global Horizontal Irradiance) measurements?
Please suggest clear sky models/techniques/formulas which can be employed using a dataset containing the following given meteorological measurements to identify clear sky days in a year.
- Daily Global Solar Radiation (GHI) : Avg,Max,Min
- Daily Extraterrestrial Solar Radiation : Avg
- Daily Air Temperature : Avg, Max, Min
- Daily Relative Humidity : Avg, Max, Min
- Daily Sunshine Duration : Avg, Max
- Daily Wind Speed : Avg, Max, Min
I intend to implement the suggested equations/formulas/models in matlab.
Your problem does not have accurate solution even if you have set up a precise definition of what is a clear-sky because your data is not sufficiently resolved in time. I backup the answer of Chris Gueymard and Frank Vignola on the use of a model predicting the irradiation under cloudfree sky, a so-called clear-sky model
As written by my colleagues, such models need inputs that you may not have though they are likely available. Given your objective, you may find an interest to use the McClear service available at http://www.soda-pro.com/web-services/radiation/mcclear.
It is a service covering the world that delivers time series of irradiation that would be observed in a specific site under clear sky conditions, with a time step ranging from 1 min to 1 month. The Global, Direct and Diffuse Horizontal Irradiation, as well as the Beam Normal Irradiation are provided. The data are available from Jan. 2004 up to current day-2. Inputs about atmosphere properties are taken automatically from the MACC (now CAMS) database. MACC: Monitoring Atmosphere Composition and Climate, a series of European-funded projects. CAMS: Copernicus Atmosphere Monitoring Service, an operational program to deliver info and data on several properties of the atmosphere (mostly aerosols and gases) and other data, among which solar irradiation at surface.
Access to data is free and unlimited provided you have registered. You may also be interested in knowing that this service obeys the Web Processing Standard of the OGC and that you may call it automatically (after registration). Help may be found at http://www.soda-pro.com/help/macc-rad/automatic-access.
Details on the model may be found at http://www.atmos-meas-tech.net/6/2403/2013/amt-6-2403-2013.htmlFollowing
- 9How to increase the yield of islets isolated from RAT?
We are injecting collagenase NB8 to the pancrease,
17 minutes in 37 bath,
Filter the suspension through a 425um diameter wire mesh
Use Histopaque to seperate the cells
and wash twice.
Do self sedimentation 6 times..
and yield only 300 islets.
How can I improve the method?
Selection of enzyme and species is important. It is important to choose an enzyme and species it pairs well with. For Rats (Wistar, Lewis, SD) we have found Collagenase XI (Sigma) at 1.5 mg/mL in HBSS works well.
Some common steps to check:
1. Pancreas distension is full, indicating injection was into common bile duct not hepatic artery. Hepatic artery injection will result in islet being preferentially digested instead of the exocrine.
2. Digestion time optimization (12-15 mins). You will probably due 3 rats at once. So, the first one at 12 min digestion, take out conical tube and with one hit about 80-100% of the pancreas should fall apart. If it does not, then digest a little and then stop reaction. You will know to extend your digestion time for the other tubes.
-You can also take dithiozone, and take a sample of the digested pancreas extract to see if intact islets are staining purple. If small fragments are staining, then you have overdigested. If you see trapped islets, then you are not digesting enough. Dr. Nunemaker's comments about islet roughness also apply.
3. Gradient purification tips. Following washing cells, pour out wash into gradient beaker. Then place conical tube, inverted, onto paper towel and let drain for about 30 sec. This will help remove excess water from tissue and help your purification.
4. Did gradient purification work as intended. Following gradient purification with histplaque, collect "other" supposedly non-islet fraction. Stain with dithizone to see where islets are ending up.Following
- 2Is there a valid methodology of identifying non-functional over-reaching or overtraining syndrome in athletes after-the-fact (i.e. no baseline test)?
I've been doing background literature and come across a number of hormones and other metabolites that may be effective at diagnosing overtraining syndrome or non-functional over-reaching. I'm interested in biomarkers that can be assessed at a basal rate. We won't have the ability to take someone through an exercise test over the course of the assessment. Can any experts offer an opinion? Thanks!
Hormonally people still use the basal free T to C ratio, but controls on confounders have to be tight. Years ago I used prolactin and still think it may be useful, but.....Following
- NewIs that a bad idea to use BFAST R package for MODIS LAI timeseries smoothing (noise removal)?
In fact BFAST is designed for seasonal and trend detection in a timeseries. However, I'm wondering if it can also be applied for noise removal that is by excluding the reminder values from the break down. Then the filtered timeseries would be a sum of the seasonal and trend components.
- 11Does anyone know about egg axis in turtles?
Could you please explain about egg axis in marine turtle? How to position the egg in order not to change the axis when one have to move it to the artificial breeding ground? Can we see the axis from external morphology of the egg? Cheers.
To my knowledge, embryo development haven't started yet within this early period, thus the egg axis hasn't established yet.Following
- 2If binaural interaction starts at brainstem; then why don't we see a bigger/clearer BIC in wave III of ABR?
Also, how reliable are BIC responses? Stollman et al (1996) article mentions a detection rate of 95-97%. Any personal or clinical experiences?
What do you mean by "reliable"? If by reliable you mean present and easily detectable in all normal listeners, a main issue with the ABR BIC is that it is small in amplitude and sometimes hard to see in background noise (especially since the subtraction procedure results in the waveform noise increasing 1.4X noise). One must ensure sufficient trials are recorded to ensure waveform noise is 1/3rd to max 1/2 the amplitude of the BIC.
As already noted, BICs for MLRs and especially N1-P2 are much larger in amplitude. Numerous pubs have shown this, for example:
Picton, T. W., Rodriguez, R. T., Linden, R. D., & Maiste, A. C. (1985). The neurophysiology of human hearing. Human Communication Canada, 9, 127-136
McPherson, D. L., & Starr, A. (1993). Binaural interaction in auditory evoked potentials: brainstem, middle- and long-latency components. Hearing Research, 66, 91-98.
Fowler, C. G., & Mikami, C. M. (1996). Phase effects on the middle and late auditory evoked potentials. Journal of the American Academy of Audiology, 7, 23-30.
If by "reliable", however, you refer to how well it determines normal vs impaired binaural processing. Well, there are few data concerning this and certainly far too few data for it to be used clinically. See for example:
Levine, R. A., Gardner, J. C., Fullerton, B. C., et al. (1993). Effects of mulitple sclerosis brainstem lesions on sound lateralization and brainstem auditory evoked potentials. Hearing Research, 68, 73-88.
Pratt, H., Polyakov, A., Ahronson, V., et al. (1998). Effects of localized pontine lesions on auditory brain-stem evoked potential and binaural processing in humans. Electroencephalography and clinical neurophysiology, 108, 511-520.
Delb, W., Strauss, D. J., Hohenberg, G., & Plinkert, P. K. (2003). The binaural interaction component (BIC) in children with central auditory processing disorders (CAPD). [Comparative Study]. Int J Audiol, 42(7), 401-412.
He, S., Brown, C. J., & Abbas, P. J. (2012). Preliminary results of the relationship between the binaural interaction component of the electrically evoked auditory brainstem response and interaural pitch comparisons in bilateral cochlear implant recipients. Ear Hear, 33(1), 57-68. doi: 10.1097/AUD.0b013e31822519ef
Hope this helps.Following
- 1Tellurium like (CdTe, CoTe, NiTe, MnTe) can be used as a biosensor or not?
Tellurium and metal tellurides
Cf. (e.g.): https://www.jstage.jst.go.jp/article/analsci/25/6/25_6_773/_articleFollowing
- 7Hello! Please I need to know how to estimate the Albedo and the emissivity for a urban area (a district)?
I found in an article that they estimated the Albedo and the emissivity from the land use cover CORINE (carissimo,B.,Dupont,DE., Musson-Genon, L., Marchand, O., 1995. Note de principe du code Mercure version 3.1 EDF-DER, HE-3395007B.) but I can't find it. Thank's for your help.
Mr. Naveen Kalra, you said that we can get info on albedo and emissivity from the site recommended by Mr. Fernando Allende Álvarez. I visited the website but I couldn't get any information that I need. If you could help I'll be very grateful.
- 5How to determine the sample size for a nationwide Population based study?
I'm designing a population-based crossectional study in which want determine the required sample size. I'm targeting pregnant women or women who have recently given birth and whose child is less than a year old. I do know the prevalence of the key outcome variable in study setting which I want to determine. However, I don't know the study population. I have calculated the sample size using raosoft sample size calculator or sample size formula for cross-sectional studies and the value is around 350. I want to conduct the study in four urban and four rural settings. I want to use the four major cities in my country and randomly select one rural setting that is close to each of these four cities. I consider the sample size of 350 to be too small.
How can I determine a larger sample size which I can proportionally distribute among these four regions?
Thanks in advance for your helpFollowing
- 3Pipe fish from Arabian Gulf
Can anyone help me with the identification of these pipe fishes collected in Kuwait, Arabian Gulf.
The specimen in the lower photograph has ca. 31 dorsal-fin rays, so it is probably not C. investigatoris which is supposed to have 19-24 dorsal-fin rays.
It is difficult to guess what it actually is, as several important characters are not visible in the photographs. It might be the Makran pipefish Bryx analicarens Duncker 1915 which has 27-33 dorsal-fin rays. Some species of Corythoichthys may have more than 30 dorsal-fin rays as well.Following
- 24Transcription factor binding site prediction?Which is the best online software for predicting transcription factor binding site on given sequence?
Hi Misha, I just pasted as FASTA sequence into ConSite, selected CREB from the available TF choices, clicked "analyze", then selected "sequence view " from the left hand side menu option. This shows my sequence with all the CREB binding sites. Some of them contain the half-sequences you were looking for. Depending on the length of your sequence this may be one way to check your sequence fairly quickly.Following
- 7What is the best method to separate unentrapped hydrophobic drug from a liposome formulation?
To find the amount of drug entrapped in a liposome, which is the best method! Dialysis or centrifugation or any other? also, please specify how we could be sure to discriminate the amount of unentrapped drug and/or released drug from the liposomes using dialysis bag.
The protocol is very simple. I equilibrate the swelled gel filtration resin (Sephadex G-75 or Sepharose 4B, for example) with the desired buffer at room temperature, then pour it into an open-top column with a stopcock at the bottom and let it settle. The size of the column depends on the sample volume. I am working with samples of 100-200 µl, so I use a 0.8 x 20 cm column. If you want to elute the column at 4oC, put it into the cold room and let it cool down. Otherwise, you can elute it at room temperature. Apply the sample to the top of the column and let it drain in, then elute by gravity with the same buffer used to equilibrate it. Keep the flow rate low for better separation. The liposomes will elute in the void volume. You may be able to see them come off the column because of their turbidity. Small molecules will elute later.
The larger the sample, or the more low-molecular-weight material you need to remove, the larger the column you should use. Long, thin columns give better separation than short, wide ones. Don't use a column that is larger than necessary because the larger the column the more dilute the liposome fraction will be.Following
- 3I am trying to conjugate antibody to PLGA nano particles. What will be the recommended molar ratio for the reaction?
PLGA molecular weight : 30000 Da
I will be using EDC: NHS chemistry and absorption.
The main problem that I am facing is when i searched for the papers the recommended amount of antibody is 400mcg/ml to 1mg/ml. I need to order the antibody and so I needed a starting point so I could plan my purchase accordingly. And if the amount required is too much it will be very coyly for us as thhe cost of antibodies is too much,Following
- 1What could cause a bright band in electrophoresis gel of PCR product?
I have a PCR product made of 2 pieces. I am doing site direct mutagenesis of an enzyme. I use PCR to create the 2 parts. I purify the 2 parts using a cleanup kit. I then run PCR a second time to assemble to the 2 parts and amplify them.
When I run on a gel so that I can cut out the appropriate band and purify for further processing, it is stuck in the well. I see some slight smearing down the lane, but most of it is in the well. There is no evidence of the 2 parts that were used as there are no bands present for the parts.
The combined gene is about 1200 bp, the parts are about 950 and 250 bp. I use a 1% gel. The 260/280 ratios were 1.86 and 1.87 for the 2 PCR parts used. I am using Bullseye Taq, but never had a problem like this in the past.
I have searched and most say it is a protein or some other contamination. But being a purified PCR products and primers, I don't see this as the case.
Could I have overloaded the well with too much product?
Any thoughts or suggestions would be appreciated.
is it possible that there is a homologous region of the 2 fragments that allows multiple concatenation thus a very long product formation from the 2 parts. The very long product would move slowly from the well. This could be tested by pcr of primers at the ends of the 2 pieces...if it produced a ladder of too long amplimers that could be the problem . Possibly restriction digest of your 2nd pcr product ( unpurified ) might provide a clue also if the wrong sizes were producedFollowing
- 1What are the formulas applied to calculate H2O2, MDA, POX, Total free amino acid and water soluble & insoluble proteins in plant tissues ?
I have the absorbence values and I want to calculate concentrations of H2O2, MDA, POX, Total free amino acid and water soluble & insoluble proteins.
I made the standard curves for each one of them, i need the final equations to obtain the concentrations and activities?
final equation : you need to enter your values for standard curves in excel , then you you make the option add trendline..you obtain your equationFollowing
- 2Are there examples of graphene based metal composites for mechanical applications?
Synthesis of composite using graphene,graphene oxide and metals.
You could consider our publications:Following
- 50What is the best or suitable protocol to detect the accumulation of reactive oxygen species in cell culture?I measure intracellular ROS using DCFH-DA, a peroxide/ redox-sensitive fluorescent probe. After treatment, neuronal cells were washed with cooled PBS on ice and loaded with 50 uM of DCFH-DA at 37 C in dark for 45 minutes. Then, cells were washed and scraped into PBS and centrifuged at 5000 g for 3 minutes at 4 C. Cell pellets were resuspened in cooled PBS and the fluorescent intensity was measured using microplate reader at ex 485 and em 535. Is this protocol OK?
I used it in my paper Alaimo et al., 2011. Neurochem int. I measure total ROS with DCF.Following
- 2Does anyone know where I could get a hold of a manual for the HP 1090 HPLC?
The instrument seems to be in working condition but I would like to replace the auto sampler with a simple manual injector. This way it should not require N2 gas to operate the auto injector. A Manual would be a great help.
By some miracle someone in my department had held on to a copy so I am good now.Following