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- 2Opamp - Integrator has been saturated if the input voltage is D.C, why?
Currently i am designing a closed loop system using a PID controller in Analog (usign OPAMP), the basic objective to maintain a constant D.C voltage across a load, if i give the input of PID controller as D.C voltage (the difference between set voltage and the reference voltage), the OPAMP(integrator) has been saturated. So, what is the solution to built a PID controller for D.C voltage control.
The integrator gives a zero voltage, if the mean value of the input signal is zero.Following
- 4Can Bayesian methods be used to account for possible bias (of uncetrain size and direction) of the data?
The usual Bayesian analysis takes a prior and updates it to a posterior, using some given data (and a probability model -> likelihood). The prior represents what we already know (believe) about the model. There is nothing like an absolutely uninformative prior, but there can be priors with very high information content (like sharp peaks at a particular hypothesis).
Now consider the experiments to measure the speed of light from Michelson and Morley. The data shows systematic differences between runs and experiments. Given we knew this variability and performed only a single experiment, how could we include the knowledge about the variabilty between experiments? I suspect that this should give wider credible intervals.
As I understand do "non-informative priors" like Jeffreys prior still assume that the data is "globally representative", so the posterior tells me what to expect given my particular experiment, but it ignored that I know that a further experiment would likely give me a different estimate.
I know that a possible solution was to actually perform several Experiments, but here I want to consider the case that I have some konwledge about the variability between experiments but that I can not actually perform several experiments [due to contraints on availability, money].
Another example: a hospital investigates the effect of a particular treatment of its patients. The data is representative for this hospital, but it is well known that the effects will vary between hospitals. If this information is available (at least approximately), is it possible to consider this in the analysis of the data that was obtained only from a single hospital?
Thanks, Keith, the paper looks interesting. I need to digest it...Following
- 2Any advice on why there is no band on gel for sample, but band for +ve control and poison PCR?
I have crushed up woodlice, serial diluted and spread plated and have growth of fungus on SDA+antibiotics.
I have also done a DNA extraction and run PCR with fungal primers, bacterial primers and have no band for the woodlouse DNA, I ran a poison tube with woodlouse DNA and the positive control and I got a band, meaning there is no inhibitor in the woodlouse DNA.
For the DNA extraction I used a kit that said to elute into DES water, I found that the samples degraded in the fridge so eluted into TE buffer, would this cause a problem, some has mentioned TE buffer being a chelator and may bind to mg and prevent the extraction from working?
I have no idea what to do now, anyone know why it may not be binding to the primers?
I would suggest that since you have been advised to use DES water. Try it. You have seen that due to binding of EDTA in TE buffer to Mg it is inhibiting your reaction.Following
- 3Does anyone know a cationic polymer like Eudragit RS-100 for Nanocapsules, but biodegradable?
I will start to work with nanocapsules and need to use a cationic polymer, like Eudragit-RS100. But, we will spray dry these nanocapsules to use in pulmonary route. As we know, Eudragit RS-100 is not a good candidate because it is not biodegradable and can be stored at the pulmonary branches. Anyone know a polymer like EUDRAGIT - RS100, but biodegradable? Thanks in advance.
Poly-L-Lysine (PLL) is another possibilityFollowing
- 11To crown or not to crown endo-treated teeth?
Many of us are faced with the question of whether to crown or not to crown endodontically treated teeth. Any guidlines or criteria available in literature?
I always tell my students:' more dentistry more trouble'. Or another one: 'look on the panoramic radiograph which tooth in the mouth of the patient has the worst prognosis: it is often the most expensively treated tooth with a crown....'.
In other words: try to avoid overtreatment, think minimally invasive and base your decission on individual risk assessment. What do we know?
- Endodontically treated teeth have a higher risk for unfavourable fracture
- More tooth reduction leads to higher risk for tooth loss and restoration failure
- Bruxism, caries risk have a higher impact on restoration longevity then materials.
So if a first molar has an mod restoration and much tissue left buccaly and lingually, I would preferably make a minimal invasive restoration. If the tooth is heavily loaded (bruxism?) make a cusp capping restoration, If your good in direct techniques, make it direct, if you're good in indirect techniques, do it indirect (combined with Deep Margin elevation?). In a high caries risk situation, go for minimally invasive solutions, more direct restorations are probably more favourable. If the endodontic treatment is done on a crowned tooth, go for a new crown (when the old crown has failed, otherwise, go for a repair).
One cannot say which solution is the best, it's all dependant from risk assessment, the wishes of the patient, and trying to be as minimally invasive as possible. And of course which skills you have as a dentist.Following
- NewTo what extent really the emmisivity changes with changes in surface roughness ?
For example, I have a thick sheet of teflon for which emissivity to be checked. It is worn out at some abrasive environment, leading to surface roughness in microscopic scale. How the emissivity of the surface compare before and after it was worn out ?Following
- 7Is there such a thing as a business case for corporate social responsibility?
It’s not just about getting better at what we do – addressing impacts throughout our supply chain – it’s about striving for the best, creating value for the business and innovating for a better world (A Definition of CSR by Nike in Andrew Crane, Dirk Matten and Laura J. Spence, 2014 - CSR Readings & Cases)
I do not think so. The main reason is because there is not regulatory framework behind CSR (this is as not being compulsory for companies). Also, there is a divergence between SMEs and Big companies in terms of resources (human factors and timing as well as financial resources). Consequently, I do not think that we could extrapolate from one case study to build up conclusions.
I am adding the same answer I provided to another colleague about CSR from a critical perspective:
Since CSR is not a standard (as defined by IFRS; IASs and ISAs), the fact that a company does not publish disclosures regarding CSR does not necessarily imply that there is not fully or partially CSR considered (for example in terms of social or economical aspects). CSR disclosures are voluntarly for entrpreises in Europe and are cost and time consuming. SMEs may apply for example an environmental aspect since SMEs tend not to have enough resources (human factor or economical-timing) to write further notes.
CSR are normally published by big companies because they have resources to do so, but again some information may not be disclosure deep enough.
I would also highlight another aspect of CSR commonly forgotten (it may potentially recent) that it is the institutional one. This is specific regulatory framework applied to some companies due to be performing in very specialised sectors that may be regulated (energy) or sectors that affect the social welfare in specific countries (connectivity in terms of airports such as in Norway, etc.) that may imply tailored standards or sections of them and it is essential to reflect this as part of CSR.
I wish this helps, AneFollowing
- 8Is there any membrane-impermeable cell tracker (tracer) which shows fluorescence only inside the cell?
I'm searching for a cell tracker/tracer which is non-fluorescent outside the cell and cannot cross cell membranes freely. Once the dye is brought inside the cell it should remain there and gain fluorescence.
Has anyone worked with something like that?
Thanks in advance
According to the description i cannot use it because it crosses the membrane freely (prior to the esterase cleavage).Following
- 18What is the best way for assessment of management support in success of an organization?
What is the best way for assessment of management support in success of an organization?
To summarize in two words: "Follow ISO55000",Following
- 7How can I calculate x and y coordinate of any color in CIE 1931 color space chromaticity diagram?
I want to calculate x and y coordinate of a given color in CIE 1931 color space. What is the practical formula for that? I am attaching herewith the information I got from internet
In order to calculate x, y coordinates we need to calculate X,Y and Z which is called the tristimulus values of a color.
You can find different matrixes to convert XYZ to RGB as well as RGB to XYZ based on various standards (Adobe RGB, Apple RGB, CIE RGB, ...) here:
- 1Can anyone recommend a questionnaire on sexual abuse and resilience?
can anyone suggest a questionnaire on sexual abuse in childhood and resilience?
Check these papers out if they are of use for you:Following
- 2If curcuminoid or curcumin is oxidized, does it produce benzo-quinone?
As far as I know, hydro-quinones and benzo-quinones have at least two hydroxyl groups and oxygens, respectively, bonded to one phenolic ring.
But the structure of curcumin or curcuminoid have only one hydroxyl group to each phenolic ring. So I'm guessing oxidation of curcumin doesn't produce quinones. But can't be sure... Does anyone help..?
I think what Rafik has replied is pretty precise. Now it is upto you to find out whether benzoquinone is finally produced or not.Following
- 3Why cannot my bicistron express?
hello, I built a Bicistronic P450 and CPR plasmid in pcw vector. It could not work well while the gene be constructed in pcw can express well respectively. I notice that the second gene can express in this bicistron. Does it mean that the first gene has expressed, but without activity?(I didnot do an SDS-PAGE)
Another question: Does the length of link sequences between two genes will affect the first gene‘s expression？
PS: my internal sequence TAATAGGTACCTAAGAAGGAGATATAATATG
bolds are stop codon and start codon; italics are RBS.
Thanks for Kevin and Jolanta. I will run a SDS-PAGE.Following
- 2Can I get exact weight percentage of any metal from EDS analysis for a catalyst sample?
If the catalyst contains different metal oxide. Then is it possible to know exact weight percentage of the metals? If not, then what is the exact technique to know that percentage?Following
- 1Can someone help in the DNA sequencing technique and recommend a book and a program for the sequence analysis?
Plz i want some help in the DNA sequencing technique, so any recommendation for a book and a programe for the sequence analysis???
- The knowledge on biochemistry on DNA and genes is most essential for DNA analysis
- it comprises of finding a gene
- it states about the comparison of that gene or genome with other gene or genome or protein etc.
- books like Author wood curren etc will guide you much on this topic
- 10What is the negative value obtained in Langmuir Isotherm Model? Is there any specific range for b constant so that the value is logical?
Hi. I have random questions regarding Langmuir Isotherm Model.
1) What does it means if I have negative intercept value for Langmuir Equation in the graph of:
Ce/qe = 1/Q (Ce) + 1/Qb
2) How do I know whether the obtained value of b constant is logical or not?
To be blunt, I would answer this new report in the same way as before.
Have you repeated the experiment at least three times to confirm that you get what seems to be the same raw data? Have you considered other models to fit your data? Have you done non-linear regression analysis on all experiments to get fitting values and their standard uncertainties? Have you propagated the uncertainties in fitting values and the experiment uncertainties to know the true confidence in your work?
With so many options for interpretation, no one can tell you what your results really mean. We can however tell you what you need to do to figure it out yourself.Following
- NewHow Much Mathematics is There in Early Mathematics Education?
I would like to hear your opinion about the current state of how much mathematics is there really in the mathematics education in primary schools today.Following
- 7Narrative inquiry: can anyone direct me to an example of a narrative interview guide?
I have developed a narrative interview guide drawing on Clandinin et al's (2007) three commonplaces but it would be useful to see other examples. Plus in narrative inquiry does anyone have a link to literature about giving the interview schedule to the participant prior to interview? I thought I would but have no evidence to support this. helen
many thanks for this generous reply and I very much appreciate the information and expertise. Thank you I have the text that you highlight and will re visit Andrews stories. In a previous study I used collaborative action research study and I was aware that when I met a group of experienced nurses that before we could begin our work on developing the study it was important for them as a group to share stories about various experiences. I always timetabled time for this over our next few meetings. On reflection this was not a new phenomenon as I began to recognise storytelling among my lecturer colleagues too. This seemed to be a way that nurse teachers shared meaningful experiences and I was very much part of this storytelling activity myself. I had already gathered some narratives from the older generation in my family and the power of the story and its content became more meaningful as I began to plan the empirical element of my Prof Doc programme. My study focuses on the career and educatonal experiences of nurse teachers and when I discovered the work of Clandinin and Connelly (via Dewey) the approach resonated with me strongly and led me to investigate this mehodogy more closely. I have developed two interview questions to initiate stories with participants and have included some follow up questions when the story comes to a natural end
· what were your hopes, desires, feelings (temporality)
· who were the people, factors involved (sociality)
· can you tell me about the environment/location where this took place (place)
I will not know the potential participants (three from across the UK hopefully) and I thought that once they have contacted me and we arranged date for interview I could forward the questions as a way of initiating a relationship by being transparent in my approach. Hence my original question, but I could not find any evidence for doing this. I hope to meet Jean Clandinin in Glasgow next year at the qualitative methods conference and I have submited an abstract for this. An opportunity to travel to Alberta and participate on a course on narrative inquiry would be fantastic but unfortunately not likely for a number of reasons. Great you may visit Ireland next year and a catch up may be possible depending on location in Ireland and dates and times. Once again thank you for such an encouraing reply Lynn. Best wishes helenFollowing
- 7How to generate Gaussian noise with certain variance in MATlab?Can anyone explain how to generate Gaussian noise, speckle and impulse noise at different variances and standard deviation values? Please help me.
SD = sqrt(1/n*sum((X-XMean)^2)); %Biased estimator.
RMS = sqrt(1/n*sum(X^2));
SD = RMS for XMean = 0 (which is the case for white Gaussian noise),
I don't think you need a reference for that. Hope that answers the question.
- NewDid anyone works with word-net affect or its related?
please i need your help in working with such database and how it handles with Arabic language, also how to implement it using any of software language?
- 3Has anyone applied SPSS tests to their antioxidant & antibacterial activity of compounds or extracts?
Has anyone applied SPSS tests to their antioxidant & antibacterial activity of compounds or extracts?
I agree with both Joao and Abdelrahim.Following
- 7Is it necessary to run stationary (panel unit root) test for panel data?
Is it necessary to run stationary (panel unit root) test for panel data? When the T =30years and N =15.
Check the following papers. The first one does not deal with cross sectional dependence. For a review and application look at the last article. You can find it in the internet /researchgate readly. Good luck.
Im, K., Pesaran, H., and Y. Shin, (2003), “Testing for Unit Roots in Heterogeneous Panels,” Journal of Econometrics, 115, 53-74.
Pesaran, M. Hashem (2004) “General Diagnostic Tests for Cross Section Dependence in Panels” Cambridge Working Papers in Economics, No. 435, University of Cambridge, and CESifo Working Paper Series No. 1229.
Pesaran, M. Hashem (2007) “A Simple Panel Unit Root Test In The Presence Of CrossSection Dependence” Journal of Applied Econometrics, Vol.22, 265-312.
Lopcu, K., & Ateş, S. (2009). Income Convergence between Turkey and EU Regions: A Panel Unit Root Approach. In Anadolu International Conference in Economics.Following
- 1Any guidance on the procedure to get the natural frequency of a plate with general boundary condition?
Pse guide on the proceedure to get the natural frequency of a plate with general boundary condition?
what is the shape of the plate and how general the boundry condition? other wise the problem is rather siple and classical eigenvalue in structural mechanicsFollowing
- 8What does FFT transform affect on the acceleration unit? Is it m/s2 in frequency domain?
I have a signal in time domain, actually, acceleration was calculated in time domain and the acceleration changes between [-4,4] m/s2. Then I did an FFT on the signal and converted to frequency domain; but the amplitude of acceleration in frequency domain is between [10e-4,1]. Why this difference? Is acceleration normalized during the FFT transform or not?
What will be the difference between unit of both the domain?
I don't know how you would interpret the spectrum of acceleration data. Why not stay in the time domain? What was your motivation for frequency-domain analysis?Following
- NewDental Mangement in The 22q11.2 Deletion Syndrome?
A 22q11.2 distal deletion is a rare genetic condition caused by a tiny missing part of one of the body’s 46 chromosomes – chromosome 22.
What is Dental Mangement in The 22q11.2 Deletion Syndrome?Following
- NewAre you interested to joint research?
Dears, if anyone interested in sentiment analysis or emotion mining research, and willing to do joint research, kindly contact me by inbox Thank youFollowing
- 4Can anyone suggest any Eye Tracking device (with weblink) for conducting cognitive experiment?
I am looking for an Eye Tracking device to conduct cognitive experiments. Easy to understand the interpretation language is the first prerequisite. It would be a nice help if some one can send me any web link with price and shipment procedure. I would like to buy this device for my Dhaka University Memory Research Unit (DUMRU), Dhaka, Bangladesh.
To spot the best device suitable for your experimental purposes, you may specify more features such as sampling rate and analysis qualiy. For low cost devices, "gazepoint eye tracker" works well. Tobii and SMI are high end brands with a relatively higher cost and more preferences regarding technical features. Good luck.Following
- NewHow do I extract DNA from Human Placenta for analysis of PMS2 gene?
I have never worked with human placenta before and now as my final year dissertation that is that type of sample that is going to be provided. I also have to do a business plan but I cannot find anywhere how much would cost me to get a sample of human placenta. Any help? Also what are the best kits ?
- NewEvanescent Waves From Newtonian Optics to Atomic Optics??
Hi everyone you know there is less literature about the Evanescent field i have found a very good book which is written by F.de Fornel the link is as attached but unfortunately i and my friends have no access to that book and also i have requested author to give me book through Research Gate but she did not give me feed back so please send me this book if you have access i shall be very thankful to you for this.Following
- NewAre there any publications mentioning formant transition durations between VV (vowel-vowel) and CV (consonant-vowel) syllables?
Does anybody know what the average duration of a vowel to vowel formant transition is compared to a consonant to vowel transition?
Check the references to these papers out if there is something useful for you:Following