Science method

PET - Science method

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I would like to incorporate micro-capsules in Melt spun PET filament. As we know Melting point of PET is >260C. What micro-capsule coating material would be suitable for this process? Also are there ways to reduce melting point of PET for yarn formation without changing its properties ?
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Thank you Vadym Chibrikov for your suggestions i will surely look into it .
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Dear colleagues,
I received this question from a reviewer:
Among different metal ions and anions, why Question: the chemosensor exhibit high selectivity towards Cr3+ only?
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The chemosensor I used to detect Cr3+ ion is a Schiff-base, and to the best of my knowledge, the related papers do not explain clearly the reason why a molecule is a selective sensor towards a specific ion.
So, my response the following:
"The sensing mechanism and selectivity towards Cr3+ can be supported by computational calculations, which estimate the sensing capability of molecules mainly basing on intermolecular interactions and compatibility between ion size and the geometry of chelating site. Hence, the selectivity observed for Cr3+ ion can be explained by its interactional and geometrical affinity to the chelating site."
Despite our response, we received a second revision in which reviewer is asking the same question!
Anyone can help me please!
Waiting for your responses.
With Thanks
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The HSAB principle also plays a crucial role here. Cr3+ being a hard acid tends to bind stronger to the hard centers in the schiff base ligand due to hard-hard interaction.
Moreover, the cavity size produced by the ligand for the host-guest interactions is ideal for Cr3+ ion to strongly bind with the ligand. For other ions, the cavity size may not be suitable for the interaction to take place as that of Cr3+.
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I am looking for reflectance, transmittance and absorptance data for some transparent polymer materials (e.g. PE, PET...). I found this reflectance calculator https://www.filmetrics.com/reflectance-calculator where some data is available.
What is the role of "medium" and "substrate" in that calculator?
I choose for example air as medium and substrate, and PET of 250 nm in the midddle. The absorbance plot looks weird in that case: at the wavelength >300 nm absorbance = 0.
For PE it is just 0 for every wavelength, so a strait line. Im I choosing wrong medium and subbstrate? The idea is that the material is used as a wall of a e.g. greenhouse or some other constuction, so it is indeed surrounded by air.
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Thomas Mayerhöfer thank you very much!
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I've got all Dicom files of a dynamic PET scan, but I cannot get the single volume of each time point and calculate the SUVbw. Are there any solutions that can split the diocm files into individual volumes in Nifti format and compute the SUV for each volume?
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Hello, as Wayne told you, an easy solution is to do using PMOD, but if you don't have it a free solution is using FSL, using the command
fslsplit - split a 4D file into lots of 3D files
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I have seen many veterans who have been exposed to severe shock waves from artillery fire. Their MRI of the brain are showing some "non-specific" changes, but there history is very typical of prolonged post-concussive syndrome and even CTE. There are tens of thousands of veterans with this condition. They are not being properly diagnosed and treated. As far as I am aware of, besides an MRI study done at Walter Reed Hospital there are no other studies using more sensitive tests, such as SPECT or PET. 
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When we think about stroke, we always think of loss of function. However, there is no reason to not have a gain of function after a stroke. I believe the Japanese are looking into this very closely and I have come across anecdotal evidence for the same. This possibility can be the result of two processes. We know that around the age of 2, there are more synaptic connections than in the adult brain. PET scanning has also shown that at that age the brain has the highest metabolism ever in a person's lifetime. At the same time there is a lot of "pruning" occurring in the white matter. This pruning, though is being done in a very controlled manner, is nonetheless not different to the injury that occurs from a stroke. The other possible way for the gain of function after a stroke is to consider the CNS as a system. When a damage occurs to a particular area and we see a loss of function, it does not mean that the deficit was the function of that injured area. We can look at this system wise and say that the deficit we are observing is the coping mechanism of the remaining intact system. In this way, an injury can result in a gain of function of the remaining intact system. One famous example is that of Demosthenes, the great Greek orator. He used to stutter, but when he put some pebbles in his mouth his speech was fluent and he was known for his oration. In this case we clearly see how the system is able to overcome a deficit by employing different circuits. If the articulation was localized to a single area that was not functioning well and causing the stuttering, then putting pebbles in the mouth would not have helped Demosthenes. Thanks.
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At what AAA size would you consider Cardiac Nuclear PET/SPECT with Lexiscan over Dobutamine Stress Echo? (outpatient setting)
How important is the potential for a hypertensive blood pressure response with use of Dobutamine?
How important is the presence or absence of a previously placed graft?
What are other clinical factors on which you would base your decision?
-comments greatly appreciated!
Deborah Williams, NP 
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Thank you for setting up this question. It is funny that I did not discover it until five years after you first asked it here! My attitude has oscillated over this time and now I am more agreed with your conclusion. I thank Biswajit Majumder for pointing to an evidence-based response. I wonder if Asif Machhada alsoAsif Machhada has supportive literature as this is somewhat different to my anecodtal experience.
Interesting also that Lexiscan/regadenoson is not available in some parts of the world, still. I presume it applies equally to other vasodilator testing such as with adenosine and dipyridamole.
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Positron emission tomography generally shows imaging of the physiology of the tumor as well as its anatomy, which is superior. It is unique compared to other cross-sectional imaging such as computed tomography or computed tomography (CT) or computed tomography. CT scans or MRIs often can not detect changes at the cellular level if the PET scan is capable of immediate changes. Identify in patient cells.
In order to image the tumor using PET or other methods, differences in basic features established in physiological and Metabolic of tumors and normal tissues. These differences include tumor surface antigens compared to cell tissues. Generally grow and DNA precursors such as thymidine and the rate of protein synthesis in tumors often increase compared to normal tissues. transport and Mixing of various amino acids, as well as anaerobic and aerobic glucose levels, are observed in tumor cells. In a wide range of Tumor types Glucose intake increases significantly compared to healthy tissues. In a typical PET system they are separated by a lead or tungsten blade detection of random photons in one shot Match with photons detected in other shots. In the diagram below, I plotted the average positron emitted energy from several desired radionuclides. Which of these radionuclides is best for our purposes?
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The question you mention is very broad! As for which is so-called "better", it really depends what type of tumour you are testing for or evaluating. As we know, different types of tumours are better analysed with different types of PET scans and I know my colleagues generally think they (PET scans) are all the same but you and I know that is not true. Most commonly, they expect if someone is said to have had a PET scan, it most commonly refers to using F18-FDG and clinicians are often surprised when it turned out to be something else (!)
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I'm trying to measure TEER of HK-2 cells cultured onto collagen IV-coated PET inserts of 0.4 um2 pores. Nevertheless, when I measure the blank resistance I get a value that I think is too high (about 365 ohm). Is there anyone who did this measurement before that got a similar value?
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Hi Vale,
I am having a similar issue with polystyrene inserts 1.13cm^2 and 0.4um pore size in house coated with Rat tail collagen type 1. The values are high and increasing! it has been a long time back though, have you found an answer?
thanks
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I ground the PET film into fine powder. Grinding was done in constantly cooled environment using liquid nitrogen. Upon doing DSC, I observed that the crystallinity of the powder (sieved to different size ranges) increased over decreasing size range. What is the explanation of this? Thanks
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Thank you both for offering some explanation. I will also look into the reference cited.
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I try to prepare activated carbon from PET bottle but in many scientific articles mention the use of N2 atmosphere in pyrolysis. However, I only have Ar atmosphere available. Has anyone ever tried this in this atmosphere? Because it doesn't work for me in this atmosphere. Could it be besause of this atmosphere or temperature? I used a temperature of 500 ° C. Thanks for any answers.
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Les cpnditions operatoirr sont exact
Meme avec Ar
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Hi all,
do you know about any commercial service which offers CryoMilling?
We have a few samples of plastics (including e.g. PET) and soils, which we need to cryomill, but since we do not need this service regularly, there is not so useful for us to buy a cryomill. 
Thanks in advance for suggestions,
Jan
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The simple polymer tests in that image incited these questions to me-
  • Why would red-hot copper wire burns with Green flame when polyvinyl chloride (PVC) is burnt on it but orange flame in case of polystyrene (PS) and polyethylene terephthalate (PET)? Is the HCl generated from burning PVC generates Cu(II) compounds upon reacting with copper in case of PVC, but not in case of PS or PET? But doesn't Hydrogen have higher reduction potential than Copper (EMF series), and copper may anyways oxidize in air at high temperature to provide a green-blue flame?
  • Why acetone reacts with PS but not PET? Acetone's (propanone) central C atom is not as much electropositive as methanal (formaldehyde), but still it can undergo nucleophilic addition. But while one alkyl group (ortho-para substituent) enhances electrophilic substitution reaction tendency in case of benzene ring of styrene in PS, two carboxylic groups in terephthalate causes benzene ring to be deactivated for electrophilic substitution in PET. Is this reasoning okay or is there anything wrong with it?
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One side is looking at density - whether it sinks or floats in liquids of different densities - water, alcohol, etc. Geologists do this with minerals - but they use bromoform (2.6 g/mL)!
the other side is using chemistry and solubility - flame tests to show presence of chlorine in PVC, what solvents different polymers dissolve in.
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I have 9 positron emission tomography (PET) images of a patient, taken at different times. I want to calculate total disintegration (cumulated activity) but I don't know where to begin.
Has anyone came across this topic before? Is there a practical reference or step-by-step guide to it? What tools do I need?
Thank you for your time and attention.
Regards
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Hi Sara,
To begin with you have to build the time activity curve (TAC) from all 9 points of your data. An x axis for time/ duration while y axis as measured PET data. From there, just integrate the TAC and the total integrate result will be your cumulated activity in activity.time (example; MBq.s). If you devide your cumulated activity with your administered activity, you will get the residence time (for this example in sec). Hope this helps.
Best Regards,
Syahir
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hi
cell culture plates usually are of two types on the basis of the materials used in construction: PolyCarbonate(PC) and Polyethylene Terephthalate(PET)...what's the difference between them in terms of application and quality?
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Hi Sina Rahimi , I am currently doing testing on different material, also using PC and PET. Depending on the pore size (there are different available) you can do different assay on your cells. With bigger pore size, cells seeded on both sides on the membrane can also interact. I am using 0.4 um pore size (too small to allow cell to go trough). I am using inserts from MERCK company and I can say that both PET an PC are opaque and don't allow you to visualise cells under a phase contrast microscope. However, other company offers clear inserts (depending on pore density) so you can monitor your seeded cells. I hope this helps!
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The European Parliament has approved a ban on single-use plastics by 2021. Currently there is a growing concern about the environmental and health issues caused by plastic and micro (nano) plastics wastes. This ban approved by the European Parliament means a scientific and economical challenge for both plastic industry and society in general, so I would like to discuss some points about it with the RG community.
Which could be the best replacement materials / products or perspective to adopt on the single-use plastics issue, which nowadays are everywhere in the daily life? Are we scientifically / technically prepared for these changes? I also would like to know if there are new proposals to deal with this challenges, and of course, deal with the existing contamination of plastics and micro (nano) plastics.
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A ban on single use plastics came in to effect in Kenya. Though a big reduction was observed, there are still clothes, bread and other items which are still in use.
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I tape PET on glass substrate before spin coating, and peel it off after. But I am worried that the peeling part can affect the electrical properties of my films. So I wonder if anyone has a better idea? How does anyone else do the spin coat on PET? Thank you!
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Did you try double sided clear tape?
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Hi everyone,
May I ask if there any ideas to fix the PET film on the glass substrate for nanoindentation test? Because PET itself is not able to attach to the substrate, if we fix the film only by using tapes adhere on four sides of the square shape glass substrate, the film might dislocate during indentation causing the results to become inaccurate. Your ideas and suggestions will be much appreciated. Thank you
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Ok no problem. Your suggestion is much appreciated. Thank you so much.
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I have some files about PET-DAT in patients, having parkinson disease. And I use spm12 implemented in matlab15b for coregistration and spatial normalization of images and voxel-based comparison. But I do not know how to measure regional uptake values for region of interests, like putamen, caudate.
Can you offer some methods and Suggestions?Thank you very much for your help.
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You nees ROIs of the regions.
Marsbar will do the trick
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I have RM-BOD (biochemical oxygen demand) bottles with part number D1001 purchased from environmental express. They are disposable and made of PET resin. Are they suitable for preserving seawater samples for pH/Alk measurements?
Thank you in advance.
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Both answers are fine.
World over Pyrex bottle stands for standard good glass bottles, it is same as Borosil which is a name of a lead manufacturer in India and other places in the world.
Make the best from the best got in the vicinity of Institute..
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I am currently trying to make TADF OLED devices with graphene as an anode. I transfer graphene to PET substrate and dope it with HNO3. During the I-V measurements, I saw some sparkles and i cannot continue the measurement because of it breaks down. I think it is related with hole injection process but i cannot find a solution.What can i do to solve this problem?
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@Eda Alemdar Have you measured the conductivity of graphene films? It is likely the problem from your graphene films due to high resistivity or low conductivity, which causes the high resistance to inject holes in your devices. This very often causes burning out the devices when you apply a current.
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Hello,
I made the PET/PLA blend in our lab. Now I need a solvent for PET dissolution of this blend. Does anyone know solvents that dissolve PET and do not have any effect on PLA?
Regards.
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Dear Maryam,
4-Chlorophenol and 2-Chlorophenol are the best solvent for PET at 100˚ C, but PLA will be degraded at 100. If it is possible, you can solve PLA at THF at 40˚ C, then separate PET. Finally, by decreasing the temperature of PLA solution, PLA can be separated.
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We want to show the surface changes to PET and PLA plastics (in pulverized form) as a proof of the UV treatment. From what I understand ATR is useful for spectral analysis of a solid, but I read that it cannot be used for "hard" polymers/powders. Are PET and PLA compatible with this method or is there something else I should look into?
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Neither of those polymers are too hard to obtain good ATR spectra. If you do the experiments carefully and run control samples you should be able to see the chemistry changes. There are a few things to keep in mind. A diamond ATR will allow you to apply a lot more pressure to the sample and using a high pressure clamp will help. Depending on the amount of treatment, you may need to be careful of the penetration depth. If the ATR element you use gets too deep a penetration, the bulk material may "wash out" the spectrum of the treatment. And if you are planning to compare to library spectra make sure you take into account (or correct for) the wavelength dependent depth of penetration. I would strongly suggest reading this
as primer on ATR.
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Hi everyone, What are the best additives to decrease crystallinity of PET? I want to provide transparent sheets with 1cm thickness.
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Hola Antonio!
Que alegria que todo vaya bien! :)... Gracias a Dios por aca todo bien :).
Si! Ya pobre cambiando los tiempos y tuve muy buenos resultados, pero quiero probar con algun aditivo que me ayude aun mas :)..
Saludos!
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I have been looking for journals and books online about the topic of Tracer kinetics. Most text have information on PET systems . However, I have yet to come across text on tracer kinetics in non PET systems. Please do assist in the form of  journal articles. Thank you!
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Even if your question is three years ago, I think I will answer for this. In a nuclear medical world now almost exclusively devoted to PET, dealing with conventional nuclear medicine is still very current. First of all, since conventional techniques are not at all all overcome by PET but in many fields, such as cardiology and neurology, not only are they still current, but neither can they be substituted by PET in routine. We must also think about the real possibilities of using a PET system, in particular for the procurement of radiopharmaceuticals in poor and poorly served areas, unless there are abundant economic resources to establish a complete PET center with cyclotron and radiopharmacy. Therefore I fully agree with the colleague who wants to be informed about the SPECT radiopharmaceutical tracer theory. If you want, you can write me since I taught this subject for years at the nuclear medicine specializing school at the University of Rome.
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Will the crystal size be bigger or smaller?
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Above, rapid quenching is referenced as a better route to obtaining amorphous PET. What temperature drop is considered a rapid quench?
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Hi all, 
I have just cloned my gene into pET and would like to check if my gene is in frame. 
Can I just translate my sequence and then do a protein blast is that a proper way of doing it?
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I have the same questions, but these answers doesn't help me
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I actually have a question regarding bacteria detachment.
I am trying to detach E. coli bacteria from my polymeric surface after incubation the sample in bacteria suspension for 1-2 hours.
as I searched using SDS will help
after 1hour of incubation I took out the sample, rinsed in PBS 2 times to remove weak bounding and then covered the sample in 0.04% SDS solution and vortex for 30min at 1300rpm in 4C temp. At the end take out the sample and then harvest the cells for counting and optical density measurement..
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Bouke Boekema thank you!
Sonication is certainly a convenient choice However, cell damaging effects of ultrasounds is different depending on the microorganism as far as I studied. since the method I am trying to develop should be used for any species and strain type of the bacteria I thought using low concentrations of detergents such as SDS would be better.
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I have designed a flexible PET antenna at 16 GHz operating frequency in HFSS, which confirms the resonant point at 16 GHz. However, after printing using DMP 2831 inkjet printer with silver Nano inks and ensuring the better conductivity after sintering when I tried to measure the S parameters, I found that the resonance frequency shifts to 11.5 GHz from 16 GHz with -15 dB of return loss, whereas the simulated result was -40 dB. My design frequency is 16 GHz, however, the dielectric constant and loss tangent that I used based on 10 GHz (3.2 and 0.022) for Mitsubishi’s NB-WF-3GF100 PET film. Since PET has single sided coated surface I printed radiator and ground plane on the same side of the substrate and used waveguide port.
I am completely screwed up. Please advise me how I can rectify this problem?
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The main factor that determines the resonant frequency is the permittivity of substrate. Try to change the permittivity value in your simulation to study the significant effects on S 11 performance.
There are two possibilities;
1) Make sure the simulation is correct especially the amount of mesh given, properties on conducting elements such as conductivity and thickness, properties on substrate such as thickness, permittivity and loss tangent
b) When fabricating, make sure your printer can provide similar dimension likes the simulated design dimension
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Ideally the software would adjust the PET signal by tissue type and provide some normative values from healthy individuals.
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Just an add-on software from the previous answer could be the Analyze by the Biomedical Imaging Resource (BIR) at Mayo Clinic.
The only disadvantage is that it accepts images where the format has to be in Analize (.img and the respective .hdr).
Plus you have to create an object map of the brain for GM and WM in order to get concentration values.
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I am interested in doing an ROI-based analysis of ADNI FDG-PET data to examine regional metabolism in their control group. I am using a coregistered volumetric MRI to create anatomic ROIS and exporting these as masks to use on the PET data. Since I'm using ROIs created from each subject’s own MRI scan, is it still necessary to do a partial volume correction, or is that something you do only if you’re warping everyone’s images into a common space (e.g. MNI)? And, if I need to do partial volume correction anyway, is it a reasonable alternative to simply erode each MRI-based ROI mask by 1 voxel all around to avoid the issue, instead of doing a more complicated partial volume correction method (e.g. segmenting a coregistered MRI image, calculating a CSF dilution factor and then correcting the raw time-activity curve of the PET in each region)?
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My mistake on my previous answer I wanted to say that this method estimates an average radioactivity and not a homogeneous for the two background regions.
Sorry for my mistake and any misunderstanding caused.
In addition to my previous answer, the Müller-Gartner method will only correct for one region (most of the cases the GM) and will not treat the other regions of the brain.
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The fluorescent dye NILE Red had originally been used for staining of hydrophobic compounds like lipids. In the last years, NILE Red has been tested and proposed for the staining of microplastic particles of polymers like PE,PET,PS etc. I was wondering what interaction leads to the intercalation of NILE Red with those carbon based polymers on the molecular level?
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Are you sure that Nile Red intercalates, as opposed to just binding to the surface through hydrophobic interactions?
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Please let me know how to distinguish the quenching due to PET, FRET and Inner filter effect???
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Himanshu,
Sorry! I only know FRET!
Good luck!
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I have a multilayer film (A/B/C/PET/PE). PET and PE are the last layers. I want to laminate this multilayer film to another PE film in a PE to PE manner (A/B/C/PET/PE-to-PE). The lamination is not working properly. What could be the cause? Can PET affect the chemistry of PE
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Well, the answer to your question (problem) is stated; low energy surface of PET substrate.
Now, if you want to make the adhesion then you need to modify (denaturalize) the surface substrate as using laser beam, electrical discharge (corona), or making holes in the substrate.
Please, let us to know your thoughts please.
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im Currently working on it, can any one help me about this?
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Or are you talking about Polyethylene terephthalate (PET)?
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I have to measure the thickness of a coating on PET fabrics.
I'm trying to use Imaging ellipsometry, but I'm realizing it is quite hard.
Any suggestions?
Thank you in advance
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If the thickness is expected is around microns you can go ahead with surface profilemeter measurement. If its very thin few < 20 nm you can try AFM near the step of the film.
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I would like to determine the actual light transmittance of the three types of PET bottles that I am experimenting with. Any ideas on how this can be done without using the usual Light Transmittance Meter? Any laboratory within the SADC region that has capacity to determine light transmittance of PET bottles?
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agree with @ Branko Livada
regards
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I want know , there is a common procedure or dissolution agent for polyethylene terephthalate (PET)?
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If PET images with ground truth is available .. Please share me the link for the same.
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Dear Bijal,
You could find lot of images as a case presentation, or clinical inference or rare case report in pubmed. Those, images will have a detailed description of the cases.
Or you could contact Radiology, Nuclear Medicine department and they could provide you few samples if they to share the data.
Thanks
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Hi there,
I need normal FDOPA brain images to run a simulation can generate dynamic PET data where it is using input function from real FDOPA images. Plus, we could make a template to be a reference for further analysis. Can anyone please help me finding these? any help is appreciated.
Looking forward to hearing from you,
Best Regards,
Yasser
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Dear collegae,
Our group developed a 18F-FDOPA template for SPM automated normalisation. It is a symmetrical and adjusted to MNI-space template that you could download from: https://www.nitrc.org/projects/spmtemplates
Kind regards,
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We need to register neuroimages to test our neurodiagnostics sofwtare. Which apps or websites are you using?
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Try 3D-SSP Neurostat, it is a free download: https://neurostat.neuro.utah.edu. We use it for all our PET related Neuro Analysis. MIMNeuro and Analyze SISCOM are better packages that are commercially available for clinical Neuro analysis; they do not have any libraries of normal like Neurostat. You will have to develop your own cohort of normals for certain analysisi.
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Looking for a free softwar that can calculates PET indices from given inputs.
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Hello Folks,
I want to coat metal alloy on PET and PC sheet using Thermal vapor deposition. i have tried number of trials but there is no good adhesion between polymer and metal. So Please suggest your ideas.
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An Ar-O2 plasma pretreatment of your substrates before the deposition would raise their surface energy. This should be at least helpful for a better adhesion
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There are different types of diagnostic tests for Alzheimer's disease. as far as I know, one of them is positron emission tomography (PET) scanning. what exactly does cause the sign of the disease on a PET image? what percentage of Alzheimer's disease can be diagnosed by this procedure? do prescription drugs affect these signs after we take the test again?
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Hi,
Currently, International Working Group (IWG) and National Institute on Aging Alzheimer's Association (NIA-AA) has proposed several biomarkers as diagnostic criteria which includes cerebro spinal fluid (CSF) amyloid beta (Aβ) and tau, atrophy on MRI, glucose metabolism on [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) and fibrillar Aβ burden on amyloid PET.
There are few regions, which acts as definite Hallmark regions for AD. You could refer to below attached papers.
(11)C-PIB-PET for the early diagnosis of Alzheimer's disease dementia and other dementias in people with mild cognitive impairment (MCI)
Structural MRI and Amyloid PET Imaging for Prediction of Conversion to Alzheimer's Disease in Patients with Mild Cognitive Impairment: A Meta-Analysis
18F-FDG PET for the early diagnosis of Alzheimer’s disease dementia and other dementias in people with mild cognitive impairment (MCI)
FDG-PET for Prediction of AD Dementia in Mild Cognitive Impairment. A Review of the State of the Art with Particular Emphasis on the Comparison with Other Neuroimaging Modalities (MRI and Perfusion SPECT)
Biomarker-based prediction of progression in MCI: Comparison of AD signature and hippocampal volume with spinal fluid amyloid-β and tau
Biomarker-based prediction of progression in MCI: Comparison of AD signature and hippocampal volume with spinal fluid amyloid-β and tau
I hope these article will help you.
Further, regarding the medication you could look into these articles
Drugs for Alzheimer’s Disease: Are They Effective?
Pharmacogenomics and therapeutic prospects in Alzheimer's disease
Cholinesterase inhibitors for Alzheimer's disease
Gud Luck !!!!
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This could be done on the basis of some PET brain studies which would further strengthen your hypothesis.
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I recommend to look at the manuscript on this subject (in the Attachment). All the best.
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How can I get uniform ZnO seed layers on ITO/PET surface after cleaning through sonication by using isopropanol, ethanol and d.i water ?
I saw the Wettability of ZnO seed layers is not perfect on the ITO/ PET substrate. How can I improve, can anyone suggest me ?
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ITO/PET substrates can be treated using a plasma asher. The power and duration are critical to make the surface hydrophilic. The ideal power is 20W to 30W with the duration of 20s to 30s. If the power is too high, the plastic PET could melt. The cleaning procedure could be improved, too by using DI water with a detergent. Hope it helps.
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The goal of this Simulation is to validate the Numerical simulation method .
I am doing Stretch blow molding Simulation for water bottle with Abaqus using the real process settings.
The problem is, rate of expansion of preform is too high in simulation compare to the real process video ( we have developed the transparent mold !!) . the cavity pressure and end shape matches perfectly with the real process. but, the inflation is not matching throughout the process.
it would be very helpful if someone can put an ideas in answer section
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thanks @Ali...will consider ur suggestions..
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What forces are involved in sticking of films on substrates?
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The adhesion of a deposited material to the starter material depends much how far the surface of the substrate is clean and free of contaminants that passive the surface. The adhesion force depends the formation of chemical bonds between the the two materials. It can be promoted by a binding layer such as oxygen between silicon surface and aluminum. The presence of native silicon oxide layer before depositing aluminum helps forming aluminum oxide. And so you see that the presence of the native oxide promoted the adhesion between the two materials.
Also one can make post anneal the film to promote adhesion.
The adhesion is can be measured by many methods the simplest of them is the pull up test where one tries to pull up the deposited film.
Best wishes
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I would like to make a mixture of a smectic liquid crystal, with some kind of polymer, cure it in UV, and create a PDLC between two PET coated ITO.
Is it possible? if so, what is the smectic i should use, and the same for the polymer for good optical and adhesive properties?
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Thank you for the answer,
Is there a way to improve the adhesion.
For example adding some kind of UV polymer to the solution and curing it between the two ITO PETS?
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I wish to deposit gold thin film on PET substrates using magnetron sputtering. Since these substrates cant sustain high temperatures, i like to know whether these substrates can be mettalised using sputtering.
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Dear Eshwar,
The plasma temperature has different meaning. I think you are talking about substrate temperature, which depends up on applied power and distance between the gun and the substrate.
Yes, you can deposit gold on polymeric substrates but make sure the substrate temperature is less than M.P. of the polymeric substrate.
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I need opaque white PET films, about 0.2 mm thick with hydrophilic surface. Are such films used in any other common process ? Can anybody suggest a source to get these at cheap rate for population survey for hemoglobinopathies in rural India with low budget by thin layer agarose electrophoresis ?
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Thanks. Yes Dr. Thoma, this is the side effect of getting used to acronyms in science, and may cause confusion on a big platform like Research gate. Another such name for the same plastic sheet is BOPP. Further, use of common trade names like Mylar and Terylene- a fabric, deep rooted in our minds are some of the terms used for the same chemical to add to the confusion !
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The Standardized Precipitation Drought Evapotranspiration Index (SPEI) requires a Di term of the difference between precipitation and potential evapotranspiration (PET) on a weekly or monthly basis. I have Di for my 17-year time series, where each day of the time series represents ~1,000,000 30x30 meter squares in a city.
The formula for SPEI is attached and is straightforward. This should be easy to calculate in Matlab. W is -2ln(P), and P is 1-F(x). I don't understand how to calculate F(x). I read that to calculate F(x) I could fit the log-logistic distribution to the Di time series, but when I tried in Matlab this didn't work due to negative values (which are common since Di is Precipitation-PET).
Since the whole purpose of the math I attached is to standardize Di, would it be appropriate for me to detrend the time series and then to find the z-score? I could do that very quickly.
Any input on how to calculate F(x) would be appreciated.
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In quantifying the SPEI is needed to used a three parameter distribution, since in two
parameter distributions the variable (x) has a lower boundary of zero (0> x <∞), whereas in
three parameter distributions x can take values in the range (γ>x <∞, where γ is the parameter
of origin of the distribution), consequently, x can have negative values, which are common in
D series (Potop and Možný, 2011)
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How to make homogeneous metal oxide (TiO2 ) paste on PET/flexible plastic substrate for perovskite solar cell applications.
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Dear Anil,
I think you need to employ low temperature TiO2 films processing in term of using PET/flexible substrate. 
Here I attached good study about low temperature TiO2 from Prof Sargent's group with PCE above 20%.
Good luck. 
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Hi, I have grown primary nasal cells on semi-permeable trans-well (PET) inserts and would like to prepare a slide (for confocal microscopy). I imagine it has to be fixed and cut out and placed on the glass slide. Does anyone know how to fixate it on the slide without it moving around so its possible to stain it ? 
Your help is much appreciated. 
Thnak you!
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Thank you very much Joseph. Your help is much appreciated. 
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Power Electronic Transformer concept have various advantages over conventional transformer..I wish to know whether PET concept is implemented in India by Public or Private Power sector electricity company..
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Efficiency of power electronics transformer is more compare to conventional, as losses are not continuous, like constant(fixed) losses, more flexible(for voltage and frequency output) and in control of power by increasing or decreasing series and parallel modules with controlled firing  angle, using light beam. With advent in semiconductor technology now are used in power transfer circuits in industry and locomotives. Power electronics transformer concept, could be of great use, in gear less electric cars, with further research......
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Prices for plastic types like HDPE, LDPE, PET, PP, PA6.
I would like to compare the prices for primary and secondary material. 
Thank you very much!
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Hi, I'm young jin Hwang from hanyang university
I made GZO solution using sol gel method.
I coated GZO and AgNW on PET substrate using spin coating with 1000 rpm .
Finally, I made GZO/AgNW/GZO transparent electrode structure.
Using 4 point probe system, I measured GZO/AgNW/GZO electrode.
But It didn't measure. 
Using Non contact resistance system, It measured 100 ohm/square.
I want to know why it didn't measure using 4 point probe system.
pleas reply~~ please I want to know why.
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All your (4 electrical) contacts on sample should be electrically active, "all 4 alive", in concert. If ONE, and only ONE contact, is bad[1], then, you get, what you are asking for (your Q.).  So, check "by 2", the electrical contacts (EC), all (4-EC[1], one EC vs the 3-others, EC) EC, whether all, "by 2" EC, together, are alive[1].  If the Resistances' conditions : R1j < 1 MOhm,  (then is OK, for your case sample, GZO... electrode,  and) then check also, "by 2 EC" all (4, vs the 3-other) contacts for a linear (?)  i-V char.
If all, above, conditions, are "OK", then you might measure the (Van der Pauw[2]) resistivity[3].
1. Take the left one electrical contact "EC" (name it, as N#1_EC) and measure (check with a DMM) the values of the Resistances : R12, R13, R14. If any of the R1j is : R1j>1MOhm, for your case, then you have to repair it, the "j_contact".
2.  Van der Pauw : Sheet Resistance method                     ;        2a.  Performing Van Der Pauw Resistivity Measurements https://www.qdusa.com/sitedocs/appNotes/ppms/1076-304.pdf               2b. https://en.wikipedia.org/wiki/Van_der_Pauw_method    ;    2c. van der Pauw, L.J. (1958). "A method of measuring specific resistivity and Hall effect of discs of arbitrary shape"   http://www.extra.research.philips.com/hera/people/aarts/_Philips%20Bound%20Archive/PRRep/PRRep-13-1958-001.pdf    ;      2d. "A method of measuring the resistivity and Hall coefficient on lamellae of arbitrary shape"     http://electron.mit.edu/~gsteele/vanderpauw/vanderpauw.pdf    http://electron.mit.edu/~gsteele/vanderpauw/vanderpauw.pdf
3.  Take (more) care, about the Van der Pauw electrical contact "EC"-topology : 4 EC not in a single line, as is shown (in your illustrative schematic of 4 electrical contacts on sample_case __.pdf).
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Dear Expert
I have monitored streamflow, rainfall with another meteorological variable. While trying to do water balance of the catchment (Himalayan) following the equation P-Q=ET, it is not fulfilling the above equation. ET is being calculated using the PM method.
I am not able to find out the reason behind it. Can you please let me know the things that can be done.
Is there any problem to use ET or else I have to use actual evaporation. Please suggest me the conversion factor if any from PET to actual evaporation.
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The water balance is often done on water year to keep soil moisture changes small when done at low flow, low water table season.  Many points already made are appropriate.  The equation as you prefer is P (input) = Q + ET + soil moisture change + deep seepage (all outputs).  As mentioned, just about every factor, even if measured to some degree, is an estimate.  If the geology is tight, soil moisture change is small or accounted for, then the ET estimate can be made, but also difficult as specific to vegetation types, etc.  In some conditions, even condensation on plant surfaces can be a difficult to measure or account for input.  In some ecosystems, ET is the greatest output.  In karst systems with underground springs entering, it is possible for water input  to come from outside of hydrologic boundary, or water outputs to appear elsewhere.  If you tend to have loosing streams, water is removed from stream to replenish groundwater or aquifer.  In some channel types with coarse substrates, hyporheic flow will often go unmeasured when measuring Streamflow Q.  So considering the conditions of each water balance period, recognizing geology, soils, location of raingauges with respect to watershed, elevation, quality of measurements or estimates, all enter into a water balance analysis and help to ensure that the uncertainties are considered and addressed when possible.  Besides the hydrology, consulting with geology, soils, climate and plant specialists or information will help, especially if P-Q does not equal or come close to ET estimate.  If you did a water balance from Oct 1 to Sept 31, for each year, check for possibility of differences in soil moisture, with streamflow and recent rainfall as surrogates or indicators that there is likely a difference in soil and water table storage.  
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There are any effective methods to completely remove antimony from PET during the recycling process?
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Some researchers such as P.C. Beard had utilized Polyethylene tereepthalate(PET) film as the sensing element for ultrasound detection, but the sensitivity and bandwidth are both confined. Is there any other good method or improved means to detect ultrasound to reach to sensitivity limit and a larger bandwidth?
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What are the best candidate molecules for in vivo radiotracer (PET) imaging of aggregated alpha-synuclein? Are anybody aware of candidate small molecules, antibodies or small peptides which have been successfully labeled with radio-isotopes and tested in e.g. animal models or post mortem human brain tissue and shown promise (i.e. specificity for alpha-syn over beta-amyloid and tau protein)?
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Today i found a videi through JOVE which is entitled with "Bioluminescence Imaging of Neuroinflammation in Transgenic Mice After Peripheral Inoculation of Alpha-Synuclein Fibrils". i attached the link may it would be helpful for you.
Breid, S., Bernis, M. E., Tachu, J. B., Garza, M. C., Wille, H., Tamgüney, G. Bioluminescence Imaging of Neuroinflammation in Transgenic Mice After Peripheral Inoculation of Alpha-Synuclein Fibrils. J. Vis. Exp. (122), e55503, doi:10.3791/55503 (2017).
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I am looking for an ESL placement test that covers CEFR Levels A1 to B1. I have already considered PET and KET, but they cover a different range. Can you help?
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Dear Mr. Pedro, 
The British Council offers a very good test which is suitable for the level you are interested in, namely "The Aptis Test". I cannot provide you with a sample, but you can go to the site and see a series of samples. The good thing about the test is that one can order a customized version of the test according to the particular needs of your students. 
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Is there any open source software for simulating or calculating runoff using Monthly Rainfall, PET and Soil information of an area? 
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they're needed for heat transfer simulation.
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In cognitive state detection and analysis. We analyze spatio-temporal brain data from MEG, fmri, PET, EEG and so on, to detect the brain cognitive states. We need to know which one of these neuroimaging  techniques gives us more information. If there is a Convincing evidence on choosing one of neuroimaging techniques. fmri, MEG, PET, EEG, or what ?
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Hybrid fNIR-EEG is the best choice. I am working with it now. Dear, Osama Hourani, if you need we can discuss about it based on my capacity.
Regards
Md. Asadur Rahman
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How will you calculate the solvent percentage from 1H NMR. for example pet ether shows 2 protons at 1.26 ppm so how will you calculate the percentage. Mol. Wt. of product is 476.236
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Pet ether is a mixture of hydrocarbons so it is not possible to assign a single value to the pet ether. 
Generally, if you have a solvent like DCM which has one solvent peak you just integrate normally and compare the number of protons in the solvent to your compound.
Calculating yield is another thing, much easier to just dry the compound and retake the nmr
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Hello!
I need to deploy a membrane integrity test (bubble point test) for radioactive "vented filters" (Millipore Cathivex - PVDF - 0.22 µm - 25 mm) used in the terminal sterilization of radiopharmaceuticals.
My main problems are:
1 - mannipulation of radioactive filters (automatized procedures are desired);
2 - seal the vent (I have a Palltronic Starflow for performing of the integrity test. But I need seal the vent of filter, and this is a problem. How I can seal the vent?).
Since now I thank for the help.
My best regards,
Robson Petroni
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Thank you for your reply, it was most hepful.
Cheers
Sofia
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I am expressing a 37 KD protein in E. coli BL21 DE3 by Pet 26b vector. How can I reach the highest level of secreted recombinant protein.
I need the secreted soluble form for better purification and not going to lyse the cells due to endotoxin release. just need to reach the highest protein level in the medium.
Should I change my cell line to a commercial one? If yes what is the best option?
what is the best medium for reaching high levels of cell density in log state?
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Did you think to use the cell-free protein synthesis strategy. It will be helpful in your case.
there are E.coli and streptomyces -based CFPS systems.
with this technique the expression takes place without the use of living cells
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for PET or SPECT tracer development?
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Hi Markus, 
This might be prone to [11C]labelling:
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I have PET type of pouch case for Li-ion batteries. It seems that Al and Cu tabs do not stick well with PET. I use vacuum sealer and the sealing temperature is not controlled by user. Commercial hot melt adhesive tapes didn't work for me. What type of adhesive tape I should use?
Thank you for your suggestions.
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Thank you for your response. In my case, the most efficient way of sealing is adhesive tapes. I'd be appreciated if there's a kind of adhesive tape that adheres both metal foil and PET together. 
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After realign of PET data in spm (realign - est & res), I found part of cerebellum is disappeared in some PET data.
This problem did not happen before. 
How can I solve this problem? 
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Did you check that the whole of the cerebellum is there before reslicing?
That image looks to me like the unaligned image was tilted, and the bottom slices of the cerebellum missing, and spm has rotated it, expanding the field of view, but not interpolating outside the available slices. Hence the slightly jagged look to the bottom of the cerebellum
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I have got a fabric from china mentioning the composition percentage as- 86% PET and 14% OP. I know the meaning of PET but facing difficulties to know about OP. Could anyone suggest any information about OP?
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is it  organophosphorus?
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I'm trying to find out whether a movement-based music therapy affects the dopamine level of patients with Parkinson's disease. I would measure the dopamine level in patients' brain by a PET scan, but I haven't found an article that would specify what exactly 'normal dopamine level' means, what the specific numbers, units are, and how quantitative PET data are analyzed. I'd really appreciate it if someone could help me out and point me in the right direction.
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Your normal data will need to come from your own control group.  Fluorodopa PET scans have previously been used to compared striatal levodopa uptake in normal controls with that of subjects with idiopathic PD and manganese exposure induced parkinsonism so you can look at papers related to this work for some guidance on study design.  Your sample size will likely be small and so unless your effect is relatively large and variance small you will be unlikely to find a significant quantifiable difference between groups.   Please be sure to do a power analysis and determine necessary sample size before you start these studies. 
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Are there any citable data, about how much of polar fleece [AKA polyester fleece, micro fleece, polar wool, vega wool, velo vool, plush, velours, Vlies, Plüsch...] fiber products [typically blankets, outdoor clothing, carpets, etc.]. are made of poly(ethylene terephtalate) [PET] and how much are from other poly(esters) [if any] ?
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I am not sure but I think that there is some production in PLA. Ask your question to Corbion. I have doubts about the production in other polyesters like PBT or PEN.
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For the development of a PET-tracer targeting PDL1, we are looking for small molecules (MW <500) with high affinity (Kd/Ki < 10nM). Can anyone suggest a good lead or reference? Does anyone have personal experience with such molecules?
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there is no small molecule available at the moment, to the best of my knowledge, only groningen has an antibody-based tracer
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Hello, I am trying to functionalize PAN filterpaper (PAN microlayer on PET) with some Amino group? Is it possible? APTES will work for this purpose? Ideally I would like an aromatic amine functionalization.
Thanks
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I assume by PAN you mean polyacrylonitrile. APTES is not a great choice, it will be a crosslinked network, but it won't be covalently attached to the surface. Perhaps you could use a plasma source to activate it, then use a silane. The dopamine route is the same idea, it wont be a covalent interaction unless you activate it. Both of these are alkyl amines too.
For getting to your aniline derivative:
Amino benzophenone plus UV light would be an excellent choice, though it would only functionalize where the UV light penetrates.
For some fancier, but very robust and complete functionalization of your substrate sulfonyl azides plus thermal curing above 120C can functionalize anything with a C-H bond. For easy access to an aniline sulfonyl azide, you could deacetylate this: http://www.sigmaaldrich.com/catalog/product/aldrich/404764
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I am facing a problem in measuring intrinsic viscosity of PET using O-chlorophenol solvent and Ostwald viscometer. It is giving me different flow times when measured at a single time, even with solvent alone. I used chromic acid to clean all the glasswares. Can anyone suggest me any possible reason for this? 
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Dear Sir,
in this type of viscometer you MUST keep the same volume of solvant or solution in the reservoir at each trial. This is contrary to an Ubelhode viscometer.
If this condition is fulfilled, than it may the range of concentration used is too high. Regards
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does anyone have experiences with the direct influence of the reconstruction matrix on the SUV in µPET? should one correct for that?
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The larger the reconstruction matrix, the lesser the so-called tissue-fraction effect will be. Indeed this phenomenon is due to the fact that each image pixel may represent the contribution of different tissue, and is more pronounced with larger pixels / voxels. The only interest in going for a smaller reconstruction matrix is to reduce pixel noise level, but this will be at the expense of increased resolution (i.e., partial volume) effects, hence  potentially leading to lesser SUV values. It all comes down to that infamous accuracy / precision trade-off.