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Dear scientific community,
i am currently trying to make more sense of the voluntary disclosure theory and the associated models. As far as i understood, the theory relies on the principal agent theory and incorporates the benefits for a company to reveal and provide more information then required by the lawmakers and other authorities. My questions are:
- Can the additional corporate reports and blog posts on sales, strategic partnerships or other aspects of the enterprise evolvement be assigned to this theory? Or is this theory strictly for accounting/ market popolicymaking?
- Is there any good literature review or paper describing the state of research on this theory?
- Is there any known paper transferring this theory into the setting of any kind of ecosystems such as platform ecosystems?
- Is there any research call to instantiate this theory for specific entrepreneurial phenomena?
I would be thankful for any advice.
Thank you a lot in advance.
Best Regards
Dimitri Petrik
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One of my paper on theory applied in Voluntary disclosure.
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Hello everyone,
I got a very confused result here. I treated cell with a drug which cause mTORC1 inhibition. In my western blot result, it shows, the redused mTORC1 group also showed a reduced the total protein level of P70S6K.(band density was quantified)
I wondered is it resonable to explain this results with the down-regulation of p-mTOR cause reduced p70S6K protein synthesis?
Thank you!
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Thanks for your answer, however what really bothers me here is not only p-p70s6k is down-regulated (which is normal under mTORC1 suppression) the total protein level of p70S6K also reduced. I don't know that can not expected because of a suppression of p70S6K protein sythesis or not since down-regulated mTORC1 will leads to a supprssion on protein sythesis.
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Among the plethora of biological modifications of proteins and nucleic acids, why is the phosphorylation process so universally abundant?
That is, compared to a variety of other possible molecular groups, is there a specific reason for biological systems to adopt phosphorus groups to the extent they do?
Is this just because of the abundance and metabolic economy of this group, or are there other considerations involved (e.g., bond energetics, physical properties, solubility etc.)
Or is this question itself misplaced? Please clarify!
Thank you :)
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Phosphorylation is not the only frequent post-translational modification found in proteins: acetylation is also fairly common. Since such modifications require a high-energy substrate to transfer the modifying group, and nucleoside triphosphates or acetyl-CoA being such common substrates, it is not surprising that phosphorylation and acetylation should be frequently found among modified proteins
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Dear fellow researchers,
while drafting an article about the importance and interlay of previous knowledge and learning with (multiple) external representations (combinations of text + pictures or diagrams etc.) Stumbled numerous times over cases of Expertise-Reversal-Effects, that seem not be explainable in the conventional terms of the Cognitive Load Theory (CLT) so far.
So, I would like to share these findings with you and to invite you to think about alternative explanations.
What is the Expertise-Reversal-Effect (ERE)?
The core idea behind the CLT is, that the better one's previous knowledge is organized (as chunks), the lesser one's working memory is loaded when solving problems or learning new contents. This holds true for most of the experimental observations. However, in some cases, high previous knowledge (HPK) leads to lesser performance outcomes than of participants with low previous knowledge (LPK). This effect is called the Expertise-Reversal-Effect (ERE): HPK learner profit less or even not from a specific treatment than their LKP counterparts.
How is the ERE explained in terms of the Cognitive Load Theory (CLT)?
For explaining this contradiction, CLT also proposes an executive moment of previous knowledge, that guides search & find processes. Those cognitive procedures could conflict with the instructional format as well as previous knowledge can conflict with the presented contents. So, as Slava Kalyuga states, "if external guidance is provided to learners who have sufficient knowledge base for dealing with the same units of information, learners would have to relate and reconcile the related components of available long-term memory base and externally provided guidance. Such integration processes may impose an additional working memory load and reduce resources available for learning new knowledge."
The fact that previous knowledge may induce additional cognitive load would explain lesser (absolute) learning outcomes of HPK learners with a specific treatment in comparison to their HPK counterparts without treatment. It would also explain lesser learning gains compared to their LPK counterparts with treatment (in case ceiling effects can be excluded).
However, it is difficult to follow this explanation for the case that HPK learners with treatment show lesser (absolute) learning outcomes than their LPK counterparts as this implies (by the interpretation of the CLT) that the instructional treatment must have had an enormous effect on cognitive load, overcompensating any advantages of previous knowledge.
Which evidences and limitations of the explanation given by the CLT have been observed?
There are convincing examples that undoubtedly trigger a cognitive conflict between the mental models of the participants and the presented information like in Schnotz & Bannert:
However, these experiments heavily (and intentionally) manipulated previous or presented knowledge to yield their effects. Most treatments we are much less pervasive and therefore their effects in terms of interference between previous knowledge and presented content (including treatment) should be milder. Furthermore, the ability to ignore treatments like signaling by color coding is not taken into account by CLT, it is however been demonstrated by eye tracking studies of Richter and Scheiter:
In this study, recall performance of HPK and LPK learners with that simple treatment equals, while for participants without treatment differ significantly as expected (cf. Fig. 3). The same for the comprehension measures in Richter, Wehrle & Scheiter (cf. Fig. 3):
Even more intriguing are findings by Kragten, Admiraal & Rijlarsdam, who report on an analysis of difficulties without any treatment of diagrams that low cognitive demanding diagrams (i.e. diagrams with low complexity) are even slightly better been understood by LPK than HPK learners. (Diagrams with high complexity instead show the expected characteristics.) Moreover, diagrams with unfamiliar conventions AND that poses high cognitive demands are being significantly better understood than those of eighter complex or with unfamiliar conventions (cf. Fig. 2):
These are some of the ERE findings that are particularly surprising and, in my humble opinion, cannot been explained in plausible way within the framework of CLT.
Is a Dual Processing hypothesis a sufficient candidate for explaining these findings?
Reading the book “Thinking fast and slow” by Daniel Kahnemann, I came across the hypothesis (to my knowledge originated by Stanovich and West) that there are two cognitive processes been postulated that govern problem solving and decision making in economics. According to that theory most cognitive processes in daily live (and learning) are done on an automated base relying on previously acquired cognitive schemata (system 1). These processes require minimal mental effort but are prone to errors. However, if system 1-processes do not lead to a sufficient solution or intentionally attention is shifted to the given problem, system 2 kicks in and starts deeper elaboration processes. So, perceiving hard to solve problems or being forced to shift focused attention to a given problem should significantly decrease error rate. Also see:
This theory has been recently applied to several fields, however to my knowledge not to learning and teaching so far and especially not to multimedia instructional design and external representations.
So my Questions for Discussion:
  • In your opinion, is there a need for an alternative explanation of the Expertise-Reversal-Effect? (And why do you think so?)
  • In your opinion, is the Dual Processing Theories a good candidate to explain the given data or are there even better ways to do so?
  • In your opinion, how to predict an ERE before the experiment based on CLT or any other theory?
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What do you think about the balance between exploring widely different designs vs. local optimization at different levels of biology (genomics, transcriptomics, proteomics, anatomy, etc.)? Which levels are more or less modular or plastic?
In the endocrine system, for example, one feels that having tropic hormones (i.e., those controlling the release of other signaling hormones at other glands) may offer a finer and perhaps more robust regulation, compared to a being where all hormones were non-tropic. However, the anatomic location of elements in these networks is not trivial. For example, in the renin-angiotensin-aldosterone system, renin is produced in the kidney, and aldosterone eventually exerts its effects in the kidney as well. However, the intermediate step by angiotensin-converting enzyme (ACE) mainly occurs in the lungs, which could introduce a delay in the regulation.
Do we have good explanations for the sites of production and action of different hormones in the body? Are there common principles to be learned as optimized by evolution in this respect? Or are happenstances/contingent evolution stronger determinants?
Thank you for sharing your thoughts!
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We used to associate G proteins to most beneficial receptor functions & β-arrestin proteins to GPCRs internalization/signaling termination … But, do you think β-arrestins could contribute to GPCRs’ desired effects? Alternatively, could G proteins contribute to the development GPCRs’ side effects?
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Hi guys,
the big problem in the field is the semantical imprecision. What do people really mean when referring to beta-arrestin-mediated signaling? What exactly is this? Is it arrestin-modulation of G protein signaling or arrestin signaling in the absence of G protein activity, ie truly G protein-indepedent signaling? For the latter there is no proof in the literature, however arrestin contribution to G protein signaling has been seen by many. If we use arrestin signaling for both scenarios, no surprise there is confusion. Inititially I liked the idea of arrestins signaling in their own right but I am afraid it is no more than a preconceived concept that does no longer hold since we have the tools to really challenge the concept. The signaling bias literature is full of papers with unsupported claims and I predict it will take years for our field to recover because some proponents of arrestin signaling are very protective of the arrestin transducer model. You cannot imagine that publishing my paper was close to impossible, I was caught in a mafia of people who tried everything to kill my paper. A nightmare for the first author, he left academic science, he was disgusted...
Anyway, when you read literature, be critical, don't believe every word of a high impact paper, look at the data and dare to come up with your own interpretation! We all have the same data in the bias field, what differs is our interpretation!
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i want a software to detect the n-terminal, hydrophobic, and c-terminal regions of signal peptides.
any one knows???
thank you
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How does the awareness that plants are intelligent can help plant scientists? May it be a new school of thought in realm of plant studies?
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Dear Jetty, very nice to hear from you again and thanks for the attached papers. As a matter of fact, I think not a separate school but a new school of thought is needed to confer plant blindness. I think if scientist can consider plants as an intelligent creature, then new approaches may be adapted to deal with plant biology issues. The fact that plants can learn and develop memory is very important I believe!
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I don't understand why in much article and book about VLC IM-DD it's written that one can use an OFDM + QAM modulation. 
The trick should be the hermitian simmetry imposed on the transmitter but, if i impose that the signal becomes real.
If the signal is real how can i transmit a QAM? How can i receive the phase?
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The OFDM is done in the Electrical domain and not on the intensity of the light. The modulated OFDM signal should be real (Hermitian symmetry ensures it) to drive the LED.
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Take a look at the notch signaling pathway in human from KEGG : https://www.genome.jp/kegg-bin/show_pathway?hsa04330
What is Fringe activating? It is not pointing to another gene or protein, it is pointing to an interaction. What does that mean?
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Fringe genes are glycosyltransferases which fucosylate the transmembrane receptor, modulating Notch signaling.
You might find more in this review: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4174579/
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Hi I am confused about the concept of signal quality index. what is signal quality index? what is the relation between signal quality index and signal strength? can we determine signal strength from signal quality index?
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As Martín Martínez stated, I don't think there is a unique definition of a signal quality index. However, if you consider for example the field of (biomedical) signal processing, by a signal quality index you usually mean a value between 0 and 1 (or 0 and 100%) that indicated how "good" (free from noise and other artifacts) the signal of interest is.
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I want to find the magnitude and phase of electric power signal i-e x(t)=220.cos(2.pi.60+pi/5) Using DFT in MATLAB  using sampling frequency 1kHz.
but I am confused about how to acquire one cycle of the sampled signal then apply DFT on that.
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You can use the functions abs and angle to obtain magnitude and phase.
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Ultrasonic backscattering signals analysis in solid media
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Hello Mario, I am not sure if you are still interested in this problem. I have gone through the codes and to be honest, I could not find any issue. However, using 'calc_scat' function in place of 'calc_scat_all' helped me to get around the problem. Please see attached the resulting figures. According to my understanding, both functions should give same results for piston transducer. I am not sure why we are getting different results. I will be happy to hear about your opinion on this.
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Steroid hormones are usually transported in the blood stream by carrier proteins. At their target cells they are released and can then either bind to surface receptors or diffuse through the plasma membrane due to their lipophilic nature. In the cell they are bound to receptors that enter the nucleus and influence gene expression. Some aspects of this model are not clear to me:
1.) How do carrier proteins in the bloodstream "know" when to release the hormones? How are target cells recognized? The ability of steroid hormones to directly pass the plasma membrane makes specificity somewhat difficult to achieve.
2.) So most steroids can pass through the plasma membrane because they are lipophilic. But then they have to travel through the hydrophilic cytoplasm to reach their destination. Are steroid hormones amphiphilic? Or are they immediately bound to a receptor protein once they pass the plasma membrane?
3.) If steroid hormones are capable to pass the plasma membrane they should also be able to pass the nuclear membrane without being bound to a receptor protein, yet this does not seem to be the case. The lipid composition of plasma and nuclear membrane is different, but can this explain the differential diffusion behaviour of steroid hormones?
4.) How are steroid hormones that have served their purpose removed from the cell? Are there deactivating enzymes? If yes, how are these regulated? Or can the steroid hormones, once released from their receptors, simply diffuse out of the cell? If this is the case, how is a "re-binding" of the hormone to another receptor protein prevented?
I would appreciate if somebody could help me with these questions and/or point me to literature that explains these processes in more detail.
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The mechanistically specific answers to your questions are complex and better answered by others. However, generally speaking:
1. Carrier proteins do not need to know when to release steroid hormones because the binding affinity between steroid hormones and their serum carriers is not very high. The off rates are probably high. When you think about the hypothalamic-pituitary-gonadal or hypothalamic-pituitary-adrenal axis, this makes sense. Serum cortisol or serum estrogen is more or less equally present throughout circulation. Its target effects are dictated by the presence of the receptors rather than the mobility of the ligand (since the ligand is everywhere).
2. The distance between the plasma membrane and various organelles looks quite large in a textbook, but this is for ease of depiction. In reality, many cells contain leaflets of ER and Golgi that are in close proximity to the PM and nuclear envelope. Moreover, in target tissues, the expression level of cognate receptors is relatively high such that there is a high probability that the steroid will collide with one of its receptors upon entering the cell.
3. I do not know if steroids can penetrate the nuclear envelope. Even if they could, they would not be able to influence transcription without being bound to their respective nuclear hormone receptors. It would not surprise me if their solubility in PM and nuclear envelope were different. All lipids are not created equally, and steroid hormones are significantly more hydrophilic than their parent cholesterol.
4. In most instances, steroids are cleared from circulation by dehydrogenases, reductases present in mitochondria and ER of the target tissue or elsewhere. Since the on/off rates of steroids are high, yes, there is continual diffusion in and out of cells. And as the serum levels of various steroids drop, eventually the intracellular level in target cells also drops. This is not only relevant for steroid degradation, but also for synthesis. For example: in early pregnancy, maternal cortisol is rapidly oxidized/inactivated by fetoplacental 11-beta-hydroxysteroid dehydrogenase 2 (11-HSD2). However, toward term, 11-HSD-1 expression increases in the chorioamnion, which reactivates cortisol and promotes a placental H-P-A feed-forward surge that ultimately triggers parturition. See this publication for more information:
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What is the best way to convert RF signals into energy . 
How we can store this energy for future use ?
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I have a plant with transfer function, I design a PID Controller and the output response of the plant along with controller can be obtained with Ziegler method.  What is meant by control signal, how to get response for it?
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It is the input to the plant, which may also incorporate the actuator transfer function, along with other model elements.
Take a dc motor as an example, with a voltage input and an rpm output:
In an open-loop configuration, with no feedback and no controller, you would set the voltage input "manually" to get the rpm that you want.
In a closed-loop configuration, with feedback and a controller, the controller is fed an error signal (the difference between the actual and the desired rpm), and the controller "works out" the voltage that should be applied for you.
For the response of the control signal U(s), I am assuming you mean with respect to a unit step change in the refernece input R(s) i.e. the desired rpm. This might be required if you want to check that your controller doesn't output crazy values, for reasonable inputs. So instead of the usual Y(s)/R(s) transfer function rearrange your transfer function for U(s)/R(s).
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What would be the confidence level of points selection for the quantification of area under a signal ?
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area of lightining
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while the data acquisition process is made with EEG signal, ordinary differential equations is enough to model that?  
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he EEG signal itself has several components separated by frequency. Delta waves are characteristic of deep sleep and are high amplitude waves in the frequency range 0≤f≤4 Hz. Theta waves occur within the 4-8 Hz frequency band during meditation, idling, or drowsiness. Alpha waves have frequency range 8-14 Hz and take place while relaxing or reflecting. Another way to boost alpha waves is to close the eyes. Beta waves reside in the 13-30 Hz frequency band and are characteristic of the user being alert or active. They become present while the user is concentrating. Gamma waves in the 30-100 Hz range occur during sensory processing of sound and sight. Lastly, mu waves occur in the 8-13 Hz frequency range while motor neurons are at rest.he EEG signal itself has several components separated by frequency. Delta waves are characteristic of deep sleep and are high amplitude waves in the frequency range 0≤f≤4 Hz. Theta waves occur within the 4-8 Hz frequency band during meditation, idling, or drowsiness. Alpha waves have frequency range 8-14 Hz and take place while relaxing or reflecting. Another way to boost alpha waves is to close the eyes. Beta waves reside in the 13-30 Hz frequency band and are characteristic of the user being alert or active. They become present while the user is concentrating. Gamma waves in the 30-100 Hz range occur during sensory processing of sound and sight. Lastly, mu waves occur in the 8-13 Hz frequency range while motor neurons are at rest.Hope it may be possible
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I have generated a DMT signal on AWG (tektronix 70002A) and then used it to modulate LED(the signal is DC-biased to have voltages above LED threshold).
The signal after photo detection is captured on oscilloscope along with the back to back signal from AWG (A direct coax connection between AWG and oscilloscope).
For back-to back connection, the Sampled data from oscilloscope (25000 sample points) is compared with the input DMT signal shape. It is observed that the input DMT signal can be reconstructed by using the samples between 15227 to 16384. Fig1. Thus the start and end points are identified within the above range.
But the signal after photo-detection (Fig2.) is totally unidentifiable for the corresponding start and end points. Will the aforementioned sample points are the start and end points for the detected signal? Does the delay due to optical and coaxial lengths create significant shift in the start and end points between the signals? Any better method to identify the start and end of the DMT signal?
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DMT is very sensitive to the symbol timing errors, so a standard synchronization is essential. The distortions from LED and PD limited the feasibility of identifying the symbol head or timing delay precisely through the method you mentioned above. 
Hope the reference will help you out.
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For example the molecular ion of R4NCl and R4NBr or R4NOAc would have same or different retention time in LCMS or HPLC?
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Hello Dr. Wahab, I should not share any of my research data, but I can answer all your questions. MS are same for two peaks. The peaks are very close - partially overlapped. I know amines can show multiple peaks - I have seen that many times. The sample was not overloaded (concentrations was low) and sample was prepared in 50% MeCN/H2O (same solvent system as the mobile phase).
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Generally, PID controller holds set of input set point which helps to reduce error rate (e). Further it gains the output signal (u). But Still there is a confusion, that how it is used in DC Motors.
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Hi Dr. Success,
I think that control textbooks like Aström & Murray – “Feedback Systems”, Dorf & Bishop – “Modern Control Systems”, Franklin, Powell, Emami-Naeini – “Feedback Control of Dynamic Systems”, Nise – “Control Systems Engineering”, and Ogata – “Modern Control Engineering”, are very helpful on the subject of PID control design.
If you are looking for papers, you are advised to search them at the following links using keywords that are relevant to your research project (which I believe that you know much better than me):
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its looking like i have very low Q range signal and particle have so much polydispersity .so the intenty showing me no damping .Is that normal in SAXS intensty?
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What device? What did you expect? Give an example of the function intensity - the scattering vector. Specify your question.
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I am modulating an OOK signal(square wave) of 100 MHz. The electrical signal after photodetection shows a frequency of 20 MHz. The amplifiers used in my system are capable of handling 100 MHz.
Can someone help me understand this difference ? Is this due to LED non-linearity or does the ratio 1:5 has some significance?
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Hi, I started the experiment from low frequency square wave (5 MHz) and obtained the following result(green-direct signal from AWG) and (pink-Signal after photodetection). It shows that there is some phase shift(delay) and also distortion. But I do not understand why the peaks are not uniform in their amplitude?
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and if i modify the above ckt so that cap will discharge during off period of clock and it will charge during on period?
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Dear Biswajit,
Your circuit configuration resembles that of the pass transistor logic with the clock controls the pass transistor whose drain is connected to VDD and its source is connected to a load capacitor. The circuit resmbles also the dynamic RAM cell in case of write one operation with the capacitor in this time is the bit storage element. As Joerg n described when the clock gets high with a voltage = VDD it will be on conducting current and charge the load capacitor to a a maximum voltage = VDD- Vth with Vth threshold gate to source voltage that is required to make the transistor start conduction. The output voltage will remain almost constant with time since any loss of charges will be refreshed by the next positive clock pulses.
As for the operation when one discharge the load capacitor in the off period of the clock, since one discharges the load capacitor in the off period of the clock , it will be charged during the pulses of the clock as described in the previous state. The output voltage on the capacitor in this case will resemle that of the clock except the rise and fall times may be larger and the maximum output voltage level will be lower than VDD by the threshold voltage.
Best wishes
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I am measuring a photoresponse of graphene devices using lock in preamplifier SR830. I would like to analyse the photoresponse dependence on back gate bias. As an easy solution, I've used computer controlled Keithley 2636B. However, whenever the bias is changed on Keithley it makes massive spikes in the signal detected by lock in. I've tried varying the chopping frequency, no result. I am quite confused, since I am not sure why this is happening. I've contacted Keithley, but unfortunately they were not helpful. I've contacted Stanford research but never got their reply. The set up configuration is as following: source/drain of the photodetector are connected as A and B for the lock in to provide A-B measurement, the drain and back gate are connected to the Keithley. It should be noted that drain has both lock in preamp and Keithley connected, this contact is also put on the ground.
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Hi Jose,
Thanks a lot for your interest in my problem, I've updated my question including the information on the set up. Please let me know whether this helps. Thanks!
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How to calculate PESQ (Perceptual Evaluation of Speech Quality) Score of any noisy speech signal, especially, whose speech signals which have sampling frequency 12 kHz.
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I want to train a machine learning model which can evaluate one's visual fatigue level caused by 3DTV though EEG signals. The problem is subjects can not evaluate themselves properly.
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It's not really my area of expertise but my first naive idea is:
Provided you can modify the content presented by 3DTV, you could present certain objects (numbers, icons, etc) in a less than obvious way (hidden in a pattern, presented by weak differences of colors, etc), at alternating locations, and only for a certain time, with breaks between appearances. Then you could instruct your subjects to press a button each time they have recognized one of these objects (known to them beforehand). The delay between appearance of an object and reaction of the subject might be proportional to the sum of visual fatigue and general fatigue. By adding tasks not related to visual perception (press another button if a distinctly audible signal is heard) you could measure the general fatigue, and subtract it from the delay of the visually triggered tasks, resulting in a measure for visual fatigue alone.
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my research includes finding the optimal values for the gains of PI controller...my model results on different max. overshoot of error signal for different gain values...however, the steady state error and the settling time seem to be unchanged for the gain ranges settings...can anyone help me find other parameter or constraint to judge the error signal other than the max. overshoot, the settling time, or the steady state error?
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Hi Mariam Abbadi
Please find attached one of my latest publications. In the Section VI-C: "Performance Comparison", you can find the equations and application of the following performance indexes:
* Mean Absolute Value (MAV) of the error,
* RMS value of the error,
* RMS value of the applied torque.
* The integral of the absolute error (IAE)
* The integral of the squared error (ISE)
Finally, it shows the line of best fit $l = mt + b$, with $m$ the slope and $b$ the offset, for each error signal. The line of best fit can be used as a prediction of the error behavior and was computed using the MATLAB function polyfit, which fits a line to the data in a least squares sense.
You can also compute the Integral of the Time Squared Error (ITSE) and the Integral  of the Time Absolute Error (ITAE). 
You can find further details about these indexes on the Book Modern Control Systems, Dorf, 12th Ed.
Best regards,
Carlos Aguilar-Avelar.
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Is it possible that there is a kind of amplifying mechanism, that just like EDFA to amplify 1550 nm optical light, to amplify ultrasound signal?
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Yes, it is possible. Key word for Google search is SASER
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In most of the voltage control loop applications, the input variables to a PI controller are reference voltage and actual voltage and the output is usually a current signal. How the controller converts the difference of two voltage signals to current signal?
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Is it possible to send electrical signale through a single conductor without electrical ground ?
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It is possible provided there isn't any DC component in your signal. Beside wave guides you could use transmission lines (single wire lines or Goubau lines). However with transmission lines, both at the sender as well as at the receiver you need an additional element with sufficient capacitance (another line, a sufficiently large piece of metal, etc.) in order to provide or receive the charge moved by the sender / moved through the receiver into or away from the line.
I don't think an axon is a valid example because there are electrochemical / physiological processes involved; and the propagation mechanism of axons includes a current through the inside as well as through the medium at the outside of the axon, so one could argue that this is a two-conductor-propagation resp. that the surrounding of the axon serves as some kind of "ground".
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- would the signal be noisy with desalted oligos? Tm around 60C.
We tend to use P32 as a radioactive label for the probe.
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the efficiency of prosphoramidite base addition is very high and oligos of hundreds of bases can now easily be made. The rate of fail additions is less than 0.5% so the amount of shortmers generated in oligos around 20-30 bases is very low and the shortmers will not anneal at the annealing temperature of 60c so I think it will be fine to use desalted oligos
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Hi everybody,
I've made a stable line for a Flag-tagged protein.
While the signal of the protein is very strong by immunoblotting, I've no signal when I blot for Flag. The positive control (a transient overexpression of another vector flag-tagged) is fine, so my antibody works.
I'm wondering if it is a matter of recognizing the epitope and, if yes, what I can do to let the antibody to bind the flag.
Thanks to anyone can help me!
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 Elena: The expected flag tag signal on your overexpressed protein may not be detectable due to many possible situations: 1. the tag is there but is hidden in the fused protein thus escaped detection; 2. the tag is not there due to degradation during biosynthesis.  This can happen either at N- or C-termini.
For (1), try to boil for 15 min in SDS/bMSH prior to loading to SDS-PAGE, and for (2) perform a peptide sequencing or MS detection for a purified fusion protein.  Good luck.
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 Which type of NAE in moss? 
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Guy Dutau,  thank you for your response
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Is there any database, from where I can collect stress ECG signal (Like MIT-BIH database)?
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Use MGH/MF waveform database in which ECG signals comprise of a broad spectrum of physiologic and pathophysiologic states. By getting into description of header file or describe record through physionet ATM tool, you can select the required record. 
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I am trying to analyze a 27 Al MQ MAS NMR spectrum of alumina but I have doubts about signals. I want to talk about the experiment and the information that I can obtain about it. 
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Thanks a lot!
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If I can also establish LOQ using a calibration curve, is it OK if my lowest level is <10 signal to noise? Or will this introduce error into my method?
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Your lowest concentration must be LOQ. Calculating LOQ by using the calibration curve gives always lower results, because the effect of the real sample is not taken into account. In chromatography is advised to establish LOQ using real signal to noise ratio.
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I would like to know which software is the most commonly used or recommended for this analysis.
Best regards,
Cristian
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I recommend to use rstudio software for this analysis and better result
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I know this depends in part on the sensitivity of the antibody, but is there a general range of ug or ng that is considered appropriate for getting a good signal? 
I don't have a manifold so I will be manually dropping 1-5uL, protein concentration is roughly 2mg/mL.  
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Hello, Jackson
It depends of the characteristics of your protein (purity, antigenicity, etc) and your Dot blot protocol (one detection antibody or doble antibodies, the substrate, etc). As Mr. Martin told you, you can do serial dilutions and try with a pilot assay, including a negative control. In our lab we had detected concentrations of tetanus toxoid as low as 0.1 ug/ml, and even less. Maybe in your case, a concentration around 0,5 ug/ml (application 5-10 ul) should be enough. If you want, you can include the starting material as control. Be sure to keep space between this control and the samples, because when the concentration is to high, usually it produces an enlarged spot.
I hope these suggestions help you.
Best regards
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Developed an amplifier circuit to power up the speaker with a signal generated from function generator in the audio frequency range with manually changing amplitude and freq. of the signal. Now I have to find the speaker cone displacement using any method. I am currently looking at current sense circuit(Low side). But not able to understand the result! Can anyone tell me the feasible method to measure the exact displacement of speaker cone? 
I also want some relationship with applied signal amplitude with displacement of speaker cone?
Please help.
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Do you have access to an accelerometer (or a LASER vibrometer or anything similar) and can you generate harmonic signals at different frequencies?
With an accelerometer you will be able to measure the acceleration of the speaker cone at a given location, which, when divided by -w^2 (w is the angular frequency in rad/s), gives you the displacement. 
a(t)=-w^2*x(t)
If you want to avoid affecting the frequency response due to the added mass, I would suggest using a miniature piezoelectric accelerometer (this can cost between 300 and 500 GBP) placed as close as possible to the centre of the piston (I would avoid placing it at the membrane).
I suppose that you can use a signal generator, but I am assuming that you do NOT have a spectrum analyser. In that case, what you need to do is to use a Stepped-Sine signal. This consists of applying harmonic signals (sine waves) at consecutive discrete frequencies. This can be a bit time consuming, depending on your frequency range, bandwidth and intended spectral resolution.
A transfer function could then be determined from the ratio between the amplitude of the response sine wave and the amplitude of the applied signal.
Assuming the system is linear, you can validate your results by repeating this process for different applied signal amplitudes.
Not sure this helps, as you will need to have some equipment available to measure the displacement of the cone (I am assuming it is a piston speaker).
Good luck!
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Some special type of proteins (opsins) play major role in sensing color  in eyes. what is the molecular structure of theses proteins and what is the mechanism of sensing of intensities and colors/wavelengths. How the opsins convert photo signal into electrical signal?
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Thanks Mr. Morad Amir Ahmad..
I want to know the mechanism.. how actually light signal gets converted into the electrical signal..
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For a single wireless link monte carlo simulation the decision variable is
Conugate( h.y) where h is channel coefficient any is received signal.
What is the decision variable for full dulpex relay simulation
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what are advantages/disadvantages of adding gaussia luciferase on N terminus than on C terminus of the protein of interest.
and would it work if I attach the gluc signal peptide at the N- terminus of the protein of interest and leave the gluciferase on the C- terminus of the protein of interest?
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To be safe, you should build both constructs and test them out. It is a matter of protein folding. Some work well when it attach to the N-terminus of your protein-of-interest, some work well when it attach to the C-terminus.
See a similar discussion on RG:
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Hi, in GSM localization  application, can anyone tell me the relationship between the signal noise measurement and the variation in signal distance.
My research field is Localization Based Services in GSM system using fingerprinting method. Which is based on the signal distance computation.
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Localization of a transmitter, just on the basis of a standard equation is fraught with many a possible loopholes. The relative measurement method or shadowing model will give better results.
Even then, a factor of uncertainty must be added to make the results realistic. This variation can be Gaussian or some other pattern. The variation has to be considered to take care of fading.
The best way to work out the variation is to take a number of readings and finding the variations from the calculated readings. RF communication and prediction is a pretty challenging task.
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I want to calculate the antisymmetry of an ultrasonic crack signal. Please guide me that how can I do that?
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It should be possible to put the pulse through a Fourier Transform after normalising the signal and measure differences in the side lobes due to distortion.
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I am studying how different filter parameters affect the perception of timbre in synthetic vowels. I have been using a sawtooth signal, which is good a signal, but sounds a bit harsh and not quite 'organic' to my liking.
Can you suggest a better synthetic (reverse-filtered ?) alternative to the sawtooth wave for filter shaping?
I wonder if we can agree upon a certain voice source - and take it as a standard for synthetic vowel stimuli? That would be a step towards further parametrization of stimuli used in psychoacoustic study of vowels and timbre perception.
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Да, статья интересная. рекомендую. Хорошо, если бы пригодилась описанная мною модель ИГВ при моделировании такого рода эффектов. В любом случае информируйте меня о результатах Ваших исследований. Мой приватный адрес: lobbormef@gmail.com
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How to decide or select a signal peptide for the overproduction of monoclonal antibody? what are the factors to be taken care of when selecting the signal peptide? answers with example will be of great help.
Thank you.
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As you consider changing the leader sequence I guess you are not using the hybridoma cells  for production.  The best sequence depends primarily on the expression system you are using. Using  Google Scholar to search for "Recombinant antibody production" https://scholar.google.ch/scholar?hl=en&q=recombinant+antibody+production&btnG=&as_sdt=1%2C5&as_sdtp=
shows many relevant papers, you can further narrow down the search according to your requirements.
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hi
signal peptides are commonly protein-specific, I wonder if there is "general" signal peptides which can be used among plants. Hereby, it would enable more convenient protein expressions in various plants.
Your responses would be really appreciated.
Thank you.
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To the best of my knowledge, signal peptides are not protein-specific (although the 'performance' of same signal peptide can vary significantly from one protein to the other). Can you provide an example of a protein-specific signal peptide?
If what you are looking for is a signal peptide that works consistently well regardless of the polypeptide it precedes then no, I think such a thing does not exist.
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Hi all,
I wanted to do the small signal analysis of NE 39 bus system for my research. Is there any software for doing the same? Could anyone guide me on how to do the same?
Thanks in advance
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Dear Joice
I suggest you to use Power System Toolbox (PST), which is developed for transient studies as well as small signal stability.
PST is free. you can download PST from this link.
good luck
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In some trial I found that using Katz fractal dimension I get 4 or 6 for two dimensional data? Is it correct if I use it as feature of the signal?..
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I repeatedly get very low plasmid after isolation recently. I tried using 3 different kits but the problem persists. I usually put my cultures for growing over night and isolate the plasmid the next morning. Any body has faced this problem before? this is specifically getting serious because every time i send my samples for sequencing they return them back cuz there was no signal or very weak signal due to the low quality/OD of my plasmid. 
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Yes Cigdem Ozen  is right.
Dear Shirin,
Plasmid you are using can be low copy plasmid. So increase in the culture volume will give you better yield. Another reason can be, if you are isolating plasmid from Agrobacterium strain rather than E.coli than you grow it for longer time to get enough plasmid for sequencing.
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I am working on a map of metal sorption in microbial samples. The basic method is to use a specific fluorescent probe to label the target metal ions, which could be excited with the proper laser, followed by the collection of the fluorescent signal to map the native spatial distribution of these metals. Hopefully this could transform the fluorescent intensity to target metal concentration. But to calibrate the signal intensity to different metal concentration is always difficult since there was no clear evidence that they process linear relationship between these. So, has anybody ever done such calibration before or have any ideas to prevent fluorescent deviation during your test?
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You may need to generate a look-up table for your samples. Non- linearity could result from background fluorescence, photo-bleaching during the calibration titration, or a non-linear response of your detector (for example, a photo-multiplier tube in photon counting mode becomes non-linear as signal intensity increases and photons hit the tube more "simultaneously"- multiple photons are counted as a single photon)
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Hello!
I did some in vitro digestions according to the INFOGEST (Minekus) protocol. When I analysed by immunobloting the different aliquots of the digestion I observed "background" signals that correspond to the size of the various digestive enzymes: pepsin but specially intense are the signals from trypsin and chymotrypsin (these last ones of a similar size of my protein of interest). 
I found some publications where is described that enzymes such trypsin and chymotrypsin can actually break up the substrate and produce chemiluminiscence...
Does someone know a way to avoid this?
Thank you in advance!
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thanks a lot for your answer! Actually I used Pefabloc to inactivate the enzimes, immediately after taking the aliquot (5 mM pefabloc in the aliquot)... that is why I didn´t understand those signals in the immunoblots... but they really match up with the digestive enzymes´sizes!
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I am modulating an optical signal with carrier frequency (1 GHz to 20 GHz). At lower carrier frequency (1 GHz), the side-bands are separated by low distance. But the distance becomes higher when the carrier frequency increased (20 GHz). How can I explain this phenomena with Fourier transform?
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@Siam Uddin: "Why the side-bands are shifted gradually for incremental modulation frequency?"
Sideband separation in GHz is equal to modulation frequency in GHz.  If the modulation frequency increases gradually, the sideband separation increases gradually by the same amount.
In terms of wavelength:
Separation = wavelength2 x modulation_frequency / velocity_light
At wavelength 1550 nm and 20 GHz modulation frequency, sideband separation is 0.16 nm.  How does this compare with your simulations or measurements?
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Which portion of the Ultrasonic Time Signal (Ref.attached file) could be considered for analyzing it for microstructural damages?
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The attached signal sims to be a CODA wave wich is a resultant after multiples scattering at the surface of the transucer. It contains shear waves and preassure waves. You should read about "Coda wave interferometry" technique to detect damage.
The short answer for your question is: you should use the whole signal.
Considering a coda wave, the signal contains randomly localiced information about the structure. Normaly to detect damage the people use 2 signals one after and one before of some small strultural change. An then they compare them using the coda wave interferometry to localize the damaga or the structural change.
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Hello, what  I want to ask: How do you decide which area of the tumour ist the best for counting? How do you go on with, if there in one slide  are areas without any signals, for example good signals in the periphere and no signals in the center ? How do you  interpretate, if there are only green ( control ) signals , is it loss of 1p or 19q, or will we have to do it again ?
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Thank you very much for your answer.
I think, it  will help us a lot in our diagnostic.
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A signal is transmitted by the transmitter and multiple rays arrive at the receiver as a result of reflections (from the flat obstacles), diffraction (from the edges of obstacles) and scattering.
How do I find the number of clusters in this condition?
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The following document may help you:
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I have generated my dataset.Now i want to train them with ANN tool of 
MATLAB.
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Thank you Aparna for your positive feedback.
yes i also agree with you delta variation (from current amplitudes) for say few steps (in the slope) if compared will giventhe required distorted region of signal.
Let me attach my file,that will show you what i want to do.I have highlighted some imp portions in pdf file.Esp a
ANN for detection(.pdf) is my main file
Rest are some reference papers.
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I started working on DSP  TMS320F28335, in pin configuration I have a set of five pins of ADC given as input of +5V to -5V, and other sset of pins ADC given as 0 to 3V. but how to proceed to give sinusoidal input to the DSP. Is it really possible to give AC signals to ADC converter
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the ratio of two 100k pot helps u in deciding the scale factor. And second stage acts as simple sign converter.
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The transient nature of the radio meteor event makes FFTs unsuitable for analysis and I am looking for alternative techniques.
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@ Muhammad Zubair Ahmad
Many thanks for bringing the CMOR work to my attention.  There is certainly much work for me to scrutinise.. 
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Hi, actually I'd like to apply the machine learning technique to extract the human intention from the EMG signals. Maybe some of you have already collected such kind of data, and I'd be very grateful if you could share it with me. Thank you in advance.
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Thanks a lot ))
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Hi,
I'm currently trying to run cudaica after using pca to reduce the number of dimensions using the following process:
- remove mean
- define number of components explaining 90% of the variance
- whiten
- ica using whitened signal
My problem now comes with trying to compute the projections from the output, and then how to reconstruct the data with the original numbers of channels.
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Dear friend
Once you have the components of the original data points, you can plot the data using n-dimensional space plots.
That will give you a clear picture.
Cheers
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ocean medium
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How is your question connected to the problem under discussion? I think, we started with one-dimensional problem...
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I am working on a research work on transmitting ECG signals compressed by Compressed sensing over wireless body area network . The signal is affected by noise and small scale fading. The normalized mean square error is used to estimate the quality of the reconstructed signal at the receiver. When I run the same m file in matlab several times, I obtain different values for the mean square error, although the same channel signal to noise ratio is used. I think this is reasonable, do you agree? If so, how can I obtain a signal value to represent the quality of the reconstructed signal at the receiver?
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Thanks a lot Mohammed Mobien , Bo Li and Яков Аронович Рейзенкинд .
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What might cause a recombinant protein not to be secreted to the extracellular matrix otherwise getting stucked in the cell. This is a domain of a recombinatly expressed extracellular protein and everything seems to be fine with the signal peptide sequence and cells looks healthy
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Most protein have latency associated peptide which holds the proteins at ECM through protein protein/carbohydrate interactions. When the activation signal comes, either it lose interaction or cleaved to release active secretory protein. This cleavage is usually made by matrixmetalloproteinases (MMPs). So it is likely that it is not cleaved, so still stuck to ECM and hence you see it in cell lysate.
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hi dear all.assume that a chaotic signal is received from the two different noisy channels. can we measure the effect of noise on a chaotic signal using the Lyapunov exponent? or you prefer another statistical or feature extraction method? thanks
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Dear Majid, 
I can recommend you to use the measure, proposed in the papers attached. This measure is connected with positive Lyapunov exponents, but enables one to determine the degree of noise influence on both regular and chaotic systems.
Best regards,
Sergey
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i have problem to measure the parameter of the signal (Frequency,Amplitude, Initial phase shift) which lower than 1Hz (ex. 0.1Hz ,0.01Hz).
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Sample for a longer period.
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I have a task to Implement boundry scan and Verify IO Pads of My design using P1500 Bcell, But as we dont have dedicated state machine for P1500 protocol as we have for 1149.1 protocol. so I want to use 1149.1 state machine and p1500 Bcell at IO pad level so is it possible??
I am not getting exact signal mapping from 1149.1 to 1500 protocol.
If anyone knows about this then let me know please....
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yes i am getting at 1149.5 with slight variations in p1500B cell
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Dear Researchers, 
Anyone can help in defining the 1-bit compressive sensing, I have some difficulties to understand how it works exactly. Is the algorithm can be applied to analog/digital signals?
Thanks,
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Recovering sparse signal from the sign of the linear measurement
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I am Infiltering my BiFC constructs along with a localization marker. The localization marker has RFP. I can very clearly see RFP signal, but I am not able to find GFP signal so far. I have already repeated my experiments three time. Any suggestions?
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I am not a plant experts but GFP signal is pH-sensitive. keep in your mind. i do not ask trivial questions like expression of proper constructs in tissue, etc.
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Hello every one, I am trying to obtain the spectrum of non-uniform sampled signal.  
Suppose the signal is sampled approximately every 10 micro seconds, and satisfies the Nyquist-Shannon sampling condition. The sampling points are:
(0±sigma)ms, (11±sigma)ms, (21±sigma)ms, (29±sigma) ms.
Where 0, 11, 21, 29 are the center of the non-uniform sampling (which are known), and sigma is the jitter level.
How can I get the spectrum of a signal with this kind of characteristic? Can I polyfit the signal and resample it? How the sigma affect the spectrum?
Welcome to discussion and thank you very much for your help.
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Look at the Lomb-Scargle method.
Also look here, if you use MATLAB:
For some reason I cannot attach an .m file here. If you are interested in a Matlab function to calculate the Lomb-Scargle periodogram, please email me at fss1@le.ac.uk and I will send it to you.
Best
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I want to create a global system to comunicate arduino and android app with a database and webpage.
First i got the raw signal from a biomedical device and store in a microsd in the arduino, next i want to send this signal via bluetooth to a android app, next save this signal in a database.
Finally i want to create a webpage that can comunicate with this Database as the android app.
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I would suggest that you upload all data from the arduino to the web server using REST protocol. this server side can be written with any programming language but I would suggest PHP or Python, since they are easy to wire up. Date cant be sent to server by adding an ethernet or Wi-Fi shield to the arduino or even with a gsm module.
Then using bluetooth doesn't become necessary again. U can write an android program to get the latest latest data when to click a refresh button or using AlarmManager you can fire up an event which retrieves the data from the the web server to your mobile device via REST. Easy Peezy.
Cheers, Goodluck.
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I have made predictive current control for dc to ac two level 3 phase. When doing THD analysis i get 8.39% whereas 5% is acceptable. How can i get the desired THD levels
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@Vishal Charan
You can try following 
1. Increase the switching frequency.
2. Check the harmonic numbers present in the current. Accordingly design filter remove those harmonics.
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Hi, I am looking into some signaling lipids from marine copepods and just found out that they are present in fresh water copepods too. Now I am trying to get  samples of  from different species. So my question is if someone has freshwater copepods of a known species in the lab and can spare me a few?
Best wishes /Erik
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Hi Erik, we do have in our laboratory but the problem is posting it across to you from Nigeria. However, if logistics & directions are provided by you , we can send it across.
Best regards.
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I am working in EEG signal by matlab I use(EEGLAB) I have a data about(5*2886000), but I have those 3 questions:
1.Is it better if we have more channel in EEG signal?
2. We have 5 row(5*2,800,000) can we change row to bigger than 5 , provided that the data does not change?
3. Why we use 5 five steps(5 times) for sub band to separate(High path and Low path)? what happen if we use more or less than 5 times ?
does it has any relation with Gamma, Beta, Alpha, Theata?
 
thanks...
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Thanks for you all
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I have sEMG data I want to apply EMD to extract features in time frequency domain. I decide to take mean frequency and power spectrum density of my IMF. how can I get frequency range of my each IMF?
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Hi, 
You can use the following work which defines instantaneous frequency such that it is always positive and valid for all kind of mono and multi component signals.  Matlab code is also available.
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which protein gets phosphorylated by PKczeta in nFkB signaling?
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Thanks Michael
I got the answer fallowing your suggestion.
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I am using PVDF/nitrocellulose membrane for blotting. I have tried different ELCs( ECL Pierce, ECL Prime and Super Signal Femto) to have better signal, and tried different exposition times. Also, I have rinsed my membrane with TTBS (tbs 10x +900ml dH2o +1ML tween20) more and less times than normal protocol. If I rinse more, frequently I have lost signal. If I rinse less than normal protocol, more dirty background appears. May I ask your recommendations on this problem how I can solve this problem? Thanks in advance.
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Dear Yalcin
I appreciate that. It is kind of you. Your answer is very helpful for me.
Thanks in advance.
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How to measure the noise of the transimpedance circuit by using the oscilloscope?shorting the interveting input terminal or opening it? And the bandwidth was measured by applying a sinusoidal signal with a resistor of several MΩ to the input,and then observe the attenuation of output voltage from the oscllloscope with the change of the sinusoidal signal frequency.This measurement way is right or wrong?
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Barrie:
Firstly, I should explain that the circuit have been designed and the photo detector is the photomultiplier.
The circuit design referred to the book "Photodiode amplifiers op amp solutions". It consists of two stage amplifications: the first stage has an op amp, a feedback resistor R1 and a feedback capacity C1; the second stage is a voltage amplifier. To meet the high gain requirement, the R1 used the metal film resistor of 100k. The C1 prevents the oscillation and reduces the noise, but it would be limit the bandwidth. The noise calculation learned from the book “Operational Amplifier Noise Techniques and Tips for Analyzing and Reducing Noise”. Can you explain the “superposition methods”? I want to learn these methods and use them.
After calculation, I used the oscilloscope to measure the noise of the circuit, but I not sure if the input terminal should be short or open it. A professor told me that a 1G ohm should be as the input resistor in series because the extremely large resistor would be produce the extremely small current noise. And then when this small current noise flows the circuit, the total output noise approximately regard as the noise floor of the circuit.      
Now I am using the spectrum analyzer to measure the noise, so I desire for some advices from you.
Thank you very much!
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Hi, 
In Statistical signal processing, lot of research is based on complex analysis. Many techniques and methods are transformed to complex domain. Whereas complex information is only important in form of magnitude and phase. So whats the difference in using magnitude information or real and imaginary information of the data?  Why is phase important? What the difference of the signal that is added with phase information and without phase information?
Appreciate your comments
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Let us consider two dimensional problems, where the power of complex analysis can be seen quite directly.
If a function f(x,y)=u(x,y)+ i v(x,y) is differentiable at z0=x0 + i y0 then at this point ux=vy and uy = -vx is satisfied. These are Cauchy-Riemann conditions. This immediately has a important consequence for quantum theory. It means that the quantum mechanical wave function (which has to be differentiable)  is analytic everywhere.
When z=x+i y and f(x,y)=u(x,y)+ i v(x,y), then if f(x,y) is an analytic function it immediately implies that u(x,y) and v(x,y) should satisfy Laplace's equation. This is directly related with Physics because then both real part and complex part of an analytic function (such as the wave function) must be harmonic. Example: The free particle wave function e i k.r .
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we do not have the fundamental frequency
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I still do not understand your task. The Fourier coefficients are not estimated but calculated according to the formulas. These formulas do not require knowledge of the fundamental frequency. If you want to evaluate the spectral content of the signal, estimate its power spectrum (Digital Spectral Analysis: With Applications (Prentice-Hall Series in Signal Processing by S. Lawrence Marple)).
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Hello,
We are trying to monitor in vivo proliferation of CD4+T cells by using CFSE labelled cells. This is what we tried so far without any success.
We purified total CD4+T cells or naive CD4+T cells from CD45.1+ mice spleen using Miltenyi kit. Then we label the cells with CFSE . We took a small aliquote of CFSE labelled cells and surface stained them with CD3 and CD4 antibodies. From that we know that the cells are very pure ( more than 95% live, 97-98% CD3+CD4+) and we saw a very bright  and narrow peak of CFSE. Right after CFSE labeling, we counted the cell number and injected either 4 million or 10 million of labelled cells in SCID mice (also cd45.1 back ground) by IV injection. Then we took down  the the SCID mice either day 2 or day 5  after injection. When we checked the spleen and blood cells  of the SCID mice for CFSE signal, we didnt see any signal above background, also we noticed less than one percent of CD3 and CD4+ cells. We are trying to solve this problem. Any suggestions will be highly appreciated.
Thanks.
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Hi there, 
did you by any chance have any depleting antibody clones in your MACS sort protocol (e.g. GK1.5 for CD4?) That could lead to loss of your cells in vivo.
Were your SCID mice congenic or could rejection be an issue (B6 vs. Balb/c)?
I agree with Simon that you get strong proliferation after injection of T cells into lymphopenic hosts and it might make sense to use CFSE concentrations that yield an initial staining signal beyond the range of the cytometer channel. However, at day 2, cells shouldn't have divided so often that you can't see the CFSE signal any more (which can track up to 6-7 generations). As Simon says, the CFSE MFI drops initially even without proliferation not only in vivo but also if you culture the cells.
Which concentration did you use? On the contrary, high concentrations might also by cytotoxic. You could try alternative tracking dyes although it should also work with CFSE. Did you check viability right after CFSE labelling? You could as a control also stick some cells in culture with CD3/CD28 activation to sort out whether your problem is the CFSE labelling or rather in vivo or inject unlabelled cells into a control animal to see if they yield higher absolute numbers.
Good luck,
Jakob
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I am working in glow discharge plasma system. Frequency of my experimental signals are 400-600Hz..I have found FIFO memorise is used for delaying a system. Can anyone suggest the electronic specifications? Is there any other method can be used for the purpose?
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It depends on your need and the strength of the signal.
May be attched design would be useful. Also, you may check the feasibility using your FIFO system. Else look for some degita delay generator.
Good luck.
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I am using FFT algorithm for a transient signal.
If I dont use average for FFT, my frequency signal is not true?Is it necessary to use average in FFT?
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Dear,
FFTs and the Power Spectrum are useful for measuring the frequency content of stationary or transient signals. FFTs produce the average frequency content of a signal over the entire time that the signal was acquired. For this reason, you should use FFTs for stationary signal analysis or in cases where you need only the average energy at each frequency line. 
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I want to extract modal parameters fro
I am using circlefit method but my modal constants(phi(1)*phi(2)) are not mass normalized and I have only FRF graph. how can I do it?
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Dr.Ghaderi
Thank you very much. your guidance was very helpful.
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We are trying to classify different waveform (1-D signal). So far we are trying Pearson correlation with the training samples, and it is working reasonably well. However, we are facing few issues:
1. The testing waveform is concatenated (in a continuous manner) and different waveform have different length. So, selecting a window length for correlation is a problem.
2. Because of the variable length of different waveform, if we classify one waveform wrong, the alignment of the rest of the waveform is messed up. So, the classification of the rest of the wave does not work well.
Is there any better way to classify waveform/signal other than correlation? What would the machine learning approach for this problem? What are the common features for classifying 1D signals?
Thank you so much.
regards,
Haider
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You can read about Dynamic Time Wrapping, which can overcome problem of varying lengths.
I think this paper (which deal with more complicated problem) might give you some ideas how to tackle the problem
Park, Alex S., and James R. Glass. "Unsupervised pattern discovery in speech." IEEE Transactions on Audio, Speech, and Language Processing 16.1 (2008): 186-197.
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Already my senior scholar developed SODAR software using vc++, but i want design a software using C# 
Is there any possibilities to design a software to find wind direction(vertical,horizontal), facsimile record,received signal in time domain,frequency domain in SODAR signal using C# or Java
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Yes, you can do it. There are number of inbuilt functions in VC++. For these, you write your own programs. It all depends on your expertise in C++  / java. Best of luck
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We measured signal X in two methods(M1, M2), and we want to compare the two signals Xm1, Xm2. What's the best method to measure the similarity between the two signals and the information content, in other words, how can we approve that the measuring methods didn't affect the content of signals ? do we need to measuring similarities or studying information content?.
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The Bland-Altman test is often performed to determine if the quantitative values measured by the two techniques fall within a desired precision of each other. If you are not interested in the quantitative values from the two different measurement methods, then correlation is often sufficient, depending on your exact needs.
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I am working on analog schematics using Cadence Virtuoso. While simulating the testbench, I specify certain rise and fall time for particular frequency. Is there any range of rise/fall time related to the frequency of the input signal I should use?
Thanks in advance.
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Thanks both of you. I would like to explain a bit more.
I am working on standard cell library. My work is to test each n every cell to make it optimized. I am working on 28nm technology and barring few exceptions; the L in my design is restricted to 48nm. My interest is to check at different frequencies. 
@Danilo; thanks for your input. Is there any physical reason behind such relations?
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Hi guys,
I recently used anti c-myc antibody purchased from Sigma (C3956) to do whole mount immunostaining. However, the signal appered somtimes. In most cases, no signal. Does anybody know this? Which antibody do you use? Any suggestion is welcome. 
Thanks a lot!
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Hi,
You can check a free antibody database at Labome.com. For c-myc antibodies, you can check the following link: http://www.labome.com/review/gene/human/c-Myc-antibody.html. For example, Santa Cruz has mouse anti-human monoclonal (9E11) and rabbit anti-human polyclonal (N-262) antibodies, suitable for IHC. Also, Invitrogen offers mouse anti-human monoclonal (9E10) to c-myc for IHC (reference: Ludwiq et al. Nature 2003). In addition, Abcam offers rabbit monoclonal (Y69) antibody (reference: Simeone et al. PLosOne 2014). I hope this comment was helpful.
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We have problems with in situ hybridization(no signal) when using DIG-labeled riboprobes but not when using biotin-labeled. Dig probes worked just fine for many years until this year. Does anyone have the same problem?
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Here. I am using frozen sections much more often.
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In the paper linked they normalize their signal using the equation sumt(Re(Rc(t)))Rc(t) = 1. However this is the first time that I've seen such a normalization. Does anyone know to use this normalization equation? Because when it comes to normalization I thought it was meant to divide the signal or vector by its norm but this method is new to me. Any help is appreciated. 
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 For instance if i have two physiological signal (ECG,BCG) for example, how can i accurately measure similarities between them? Is mutual information an option? Please help me out.
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In the beginning i did not get the required correlation coefficient for my  ECG and BCG data, the values were too low -0.06 etc., but I tried this only because ECG and PPG signals were compared similarly (atleast HRV analysis). Hence thought mutual information could help but I was not sure.
Now i seem to get a good value for cross correlation coefficient itself. I had missed a peak or two in my previous analysis. :)
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I would be grateful if someone could recommend me some good introductory resources to the application of graph theory analysis to EEG signals.
Thank you in advance
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I am a research scholar of I.S.M dhanbad, my research area is sensor development. I got non linear out put signal like quadratic so i want to change in linear so any one have idea please give me.
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There is simple square root amplifier circuit based on OpAmp and feedback with MOSFET. Figure 16 on link
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hello researcher, i just want to ask if the discrete wavelet transform can extract each individual harmonic frequency alone of a distorted signal or it only extracts the fundamental??
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Term fundamenal frequency is for Fourier transform, where we have very large support fuction for basis functions. In case of DWT we use small support fuction and  you will get  smoothed signal (low-pass filtering) and resulf of high-pass filtering, which are denoted earlier as  low frequency and high frequency components. In you know only Fourier transform, try to read about short-time fourier transform - wavelets are kind of similar, but they have another basis functions. About experts - I use DWT since 2003 and we can talk about frequency response, low-pass and high-pass filtering in DWT.  You can try to use set of filters to get the signal in desired frequency band like in image https://en.wikipedia.org/wiki/Wavelet_transform#/media/File:Jpeg2000_2-level_wavelet_transform-lichtenstein.png. So you can check if something exists at desired frequency.
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There are many ways to normalize data. When it comes to neuronal activity indicated by GCaMP, which way is better considering the biological meaning?
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Hi Qian,
I am not sure why (perhaps a founder effect), but the most traditional way to report Ca2+ indicator signal is dF/F0. 
However, a change in that measure tells you very little in terms of biological activity (it's just a relative approximation of the concentration of calcium). You'll likely benefit from further processing to infer the underlying activity.
For example, nonnegative matrix deconvolution is often used to estimate the spike trains that cause the calcium signal increase. 
Edit: just saw you are interested in GPCRs so likely not using GCaMP strictly to infer spike activity but rather to see the GPCR activity. For that there is no need to deconvolve. See for example this publication from a member of my lab.
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Dear all, 
I am wondering if there is anyway to develop a positive control for ROS generation study in plants. In principle, I have higher signal in stressed plants compared to non-stressed but our concern is to validate if the signal really associated with ROS. So, I am just wondering how can I generate ROS in healthy plants and then compare the strength of signal with both stressed and non-stressed plant parts. Do you have any suggestion(s)?
Thanks in advance.
Muhammad
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Abiotic or biotic stress in plants trigger ROS generation . One may, however, use methyl viologen (paraquat) that generates superoxide and eventually hydrogen peroxide as positive control. More interesting would be to use inhibitors of cell wall bound NADH-peroxidase (salicylhydroxamic acid, sodium azide) or plasma membrane bound NADPH-oxidase (diphenylene iodonium chloride, imidazole) that inhibit generation of hydrogen peroxide or superoxide, respectively, as negative control that would help to check if the signal ROS-specific.