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  • Can anybody give me paper or case study that use caption evaluation method on cityscape, signscape, streetscape or anything about city of image?

    In order to know the relation or interaction between people and their built environment. Not only the caption method, any method is ok

  • Oxygen carrying oxygen preservation solution?

    Hey all,

    Does anyone have any suggestions for organ preservation solutions that can carry a significant amount of oxygen (> 25 % whole blood)? Most crystalloids (e.g., UW, Celsior etc.) can carry some but not enough for my purposes.

    Thank you



    Judocus Borm · Reinier de Graaf Groep

    -1- Animal research has been done in the past on a number of fluorocarbons as oxygen carriers.

    -2- Also "arificial blood" using hemosomes [haemoglobin contained in erythrocyte sized artificial membranes has been tried [as a solution to the need for 'universal' blood that can be given withouth typing and matching].

    With regard to the latter, the following link is useful and critical:


    With regard to my first option: various liquid breathing experiments have been done, even in humans.

    What I wonder, is, whether it would be possible to combine the fluorocarbonic approach with the hemosomic approach: making "hemosomes" or better renamed "hemosome-like" small droplets of a suitable fluorocarbon, embedded in a suitable [phospholipid] membrane. I think that kind of system leaves you more and easier controllable parameters to optimize its properties for your purposes and avoids handling hemoglobin / recombinant hemoglobin, thereby avoiding a considerable lot of potential issues if it is to be used in humans [easier registration and easier approval procedure].

  • Miloudi Hlaibi added an answer in LC-MS:
    How to separate two isomers oligosaccharides using LC-MS?

    Hi, I'm developing an LC-MS method for the quantification of 15 human milk oligosaccharides but I'm having trouble separating two isomers (LNT, lacto-N-tetraose and LNnT, lacto-N-neotetraose). I want a good resolution between them, affecting as little as possible the other oligosaccharides.

    I'm using as mobile phase water and acetonitrile, both with 0.1% formic acid and a Hypercarb column (100x2.1mm, 3u, Thermo Scientific). The LC gradient is 0-12%B in 21 min; 12-40%B in 32 min; 40-100%B in 37 min; 100%B in 42 min; 0%B in 43 min, keeping at 0%B up to 55 min. I've tried several changes in the chromatography, but the best I got is in the image attached.

    Does anyone have an ideia what I could try?

    Miloudi Hlaibi · Faculté des Sciences Ain Chock - Casablanca

    You can use the technique of chiral functionalized polymeric membranes is a very promising technique

  • A.A.P. Paraskevopoulos added an answer in Inductor:
    Is there any mutual inductance between the inductors in the equivalent transmission line model ?

    In the following figure of an equivalent TX line model is there any mutual inductance between the inductors?

    A.A.P. Paraskevopoulos · National Technical University of Athens

    Dear Mr. Ray, as I can figure out, you are refering to the distributed line model, where current and voltage are not examined as in most circuit cases, because here the electromagnetic wave and the wave impedance take place. The distributed parameters are taken into consideration in order to determine the wave impedance of the line. If this is the case you may not consider mutual inductances.

    On the other hand, if the wave phenomenon is not taken into account and the line is being considered as a normal circuit, then, YES, there is a mutual inductance between reactors. For instance in a 3phase line, each line has an inductance, but there is also a mutual inductance between lines, or even between line and earth. 

    If the line is not long and/or the frequency is low the mutual inductance could be calculated. If the line is too long or the frequency is high, then the wave effect takes place, the circuit elements are embeded into the wave impedance and the mutual inductance may be ignored. 

  • Sergio Ferro added an answer in Citrates:
    How can I prevent formation of sediment when hypochlorous acid mixes with citric buffer?

    I added hypochlorous acid (prepared and filtered from calcium hypochlorite solution) into a citrate buffer (mixture of 3M citric acid and 3M sodium citrate, ratio 40:60). I found that a layer a hard, solid, white sediment at the bottom. I suspect the sediment is calcium citrate.

    Any idea what's the sediment? How to prevent the formation of sediment? 

    Sergio Ferro · University of Ferrara

    I have no direct experience with calcium hypochlorite: what happens when you dissolve it in water? Maybe a precipitate of calcium hydroxide is formed, together with hypochlorous acid

    In that case, your procedure would be correct. However, I would check the pH with a pH-meter: if the solution is alkaline (as I think), you are still working with hypochlorite and a correction of pH is needed. Adding a small amount of sulfuric acid may be of help: calcium sulfate precipitates, and hypochlorous acid is formed. This addition must be done with care: if an acidic local pH is obtained, chlorine may evolve.

  • Which algorithms one can use for matrix inversion (for beamforming application MVDR/LCMV) in Fixed Point ?

    I have implemented beamformer(MVDR/LCMV) for speech enhancement in matlab, now I am trying to convert it to fixed point implementation. during the weight calculation step correlation matrix inversion is required, but in fixed point implementation  correlation matrix inversion is not giving correct results(may be due to very small values in correlation matrix).

    Eduardo Aguirre Romero · Instituto Tecnológico de Sonora

    if the valúes of the correlación matriz are too small, you try to increase the amount of bits that you are using for represent the fraccionary part and to use full precission in your operations. Also, you can observe the SQNR after each math operation in order to identify where are you increase the fraccionary bits.

  • Jiateng Guo added an answer in 3D Reconstruction:
    How could I make 3D reconstruction from just images, and what key technologies and research areas does it involves?

    How could I make 3D reconstruction from just images, and what key technologies and research areas does it involves?

    This is not like traditional photogrammetry technology, it depends on computer vision. 

    Like PhotoScan software, load images, and directly obtain dense point cloud to conduct 3D reconstruction, without any other interactive operations. 

    How could I implement it? what key technologies and research points are there? Thank you.

    Jiateng Guo · Northeastern University (Shenyang, China)

    You can try the software "VisualSFM" based on multi-view 3D reconstruction technology, by which you can reconstruct 3D models from just series of photo images. http://ccwu.me/vsfm/

  • What is the impact of xylem and phloem pH on the mobility of nutrients in plant body?

    Xylem and phloem pH might differ among species and environmental conditions. Is this pH affect the mobility of nutrients within plant body? If Yes then Why... Explain please....

    Francisco José García Breijo · Polytechnical University of Valencia

    Some studies shown that nitrate and total ionic concentrations (cations+anions), and the proportion of cations influenced xylem pH such that xylem pH increases as nitrate and total ionic concentrations decrease, and the proportion of cations increases (DOI:10.1093/jxb/err370). Also osmotic stress conditions can influence the pH of the xylem. The pH value of xylem sap increased under osmotic stress.

  • How to compare the model simulated spatial pattern with observed one? If inconsistency is found, how to design a feedback to improve the simulation?

    How to compare the model simulated spatial pattern with observed spatial pattern? And, if inconsistency is found, how to design a feedback to improve the simulation?

    Thomas Buchsbaum · Triemli City Hospital

    In medical physics a concept called Gamma Analysis is used to compare dose distributions to each other. The basic idea is to combine a distance-to-agreement measure (spatial shift) with a error of output measure, in some sense similar to a total least squares approach.

    The original papers are by Daniel A. Low. (attached)

    If your space-dependent output variable is continuous this approach might work very well also for your problem.

    The spatial-averaged gamma values or the fraction of points fulfilling a certain gamma criterion could be used as an objective function for optimizing your simulation model (parameters).

    [Alternatively you could try to define your specific likelihood function ("How likely is it to find your measured spatial distribution given that the expected distribution equals the simulation output). (I think, if you consider independently normally-distributed output and space errors that would lead to something similar to the Gamma value described above)]

  • Anyone knows a case of a social-ecological system illustrating the human capacity of learning and deliberate transformation to increase resilience?

    I am searching a paper on a case of a SES (social-ecological system) that illustrates the human capacity of social learning, enabling deliberate transformation of the SES, for example to a higher scale of governance, thereby possibly increasing resilience. I am looking for an example for any kind of deliberate transformation, e.g. in urban management, fisheries, forest management, protected areas, community building, etc; it doesn’t have to be a governance scale transformation, but ideally a system that undergoes the adaptive cycle phases and where a deliberate transformation led or might lead to increased resilience. Does anyone know of any such case? Thank you.

    Erin Gleeson · Universität Bern

    Hi Tobias,

    I don't think this answers your question directly, but you might find the attached paper by Sendzimir et al interesting (e.g., fig 10).

    Your question attracted my attention because it's something we are quite interested in at the Mountain Research Initiative here in Bern. We currently have four major "efforts" we are trying to encourage the mountain research community to focus on, one on assessing sustainable mountain development and the other on developing a more systematic and synthetic approach to understanding the structure, function and evolution of agency and governance in mountain regions. Your question is quite relevant to both! If you get some more helpful answers, please share!

    I see you're in the MRI database- great! Will you be attending the Mountains of Our Future Earth conference in October? It would be great to have some more perspectives from the social sciences in particular.


    (MRI Regional Networks Development and Communications)

  • Mehmet Onal added an answer in FactSage:
    Does anyone has access to TDNucl database of Factsage?

    If so, could you please share the thermodynamic data of ternary compounds of FeO1.5-BO1.5 and FeO-BO1.5 binary systems? There are 5 of them in total and I would like to introduce these compounds manually to Factsage.

    Mehmet Onal · University of Leuven

    Dear Ming,

    My email address: mehmetalirecai.onal@mtm.kuleuven.be

    I will be waiting for your email. Many thanks!



  • Kamilia Laarej asked a question in Platelets:
    How to make sure that your platelet population is not contaminated by leukocytes, what is the best way to isolate total RNA from platelets?

    RNA isolation from platelets for miRNA studies.

  • Miloudi Hlaibi added an answer in RID:
    What is a good method to separate a peptide fraction from a large amount of lactose and other sugars?

    Currently, I use prep C18 LC, but I'd like a simpler method. Basically, I'm working with a powder that is 97% sugar and 3% peptides. I want to get rid of the sugar and just keep the peptides. Is there any non-chromatography approach to do this. Some sort of precipitation, perhaps? Or a liquid-liquid extraction. 

    Note: these peptides are too small to precipitate with Ethanol, they are just fragments of bigger proteins, maybe 5-50 AA in length. 

    Miloudi Hlaibi · Faculté des Sciences Ain Chock - Casablanca

    Try using the technique of size exclusion chromatography  (SEC) with an adequate column

  • Can anyone suggest how I can start work on T1 weighted MRI brain images using VBM?

    Please suggest how I can start work on T1 weighted mri brain images using VBM?

    Amirhussein Abdolalizadeh · Tehran University of Medical Sciences


    There are many tools that can be used for Voxel-based Morphometry, e.g. FSL and SPM. If you're not familiar with linux and batch coding I suggest you use SPM, which is a MATLAB based toolbox (you can find the latest SPM [SPM12] and installation notes here: www.fil.ion.ucl.ac.uk/spm/).

    There's a toolbox which can be installed within SPM named VBM (http://www.neuro.uni-jena.de/vbm/). Note that if you're going to use this VBM toolbox, it would be better to install SPM8 rather than the SPM12, to avoid some unexpected errors.

    I myself prefer using the SPM12 itself and follow the steps being told by Joseph above. It uses some new registration methods that are more reliable. Note that the "New Segment" is available under the name of "Old Segment" in SPM12.

    You can use this manual for Voxel-Based Morphometry. Old, but gold:



  • Where can I find information about the design of the chassis of a harvester?

    can anyone help me on where to find information for the design of the chassis of a harvester, patents ,papers articles or some other means of obtaining information about it

    Govind Autee · Marathwada Institute of Technology

    Umakant Bastewad, FEA CAE Engineer at John Deere

  • Can video capture tool help to improve learning of higher education students?

    We are adopting different e-learning tools to support our classes. Video capture tools are also one of them. Can we use these tools to support students who are weak in understanding the lecture? Can it improve cognitive empowerment of the students in higher education?

    Fiona Ellis-Chadwick · Loughborough University

    Hi  Habib, Thanks for the info, that's useful. We have many students from SE Asia on our masters programmes and I must agree for these learners to be able to go back to look at lecture content is really beneficial. I'll check out the software. 

    We are developing a new blended learning design for our New Masters in Marketing programme and intend to do some research into effectiveness of different approaches and use of technology before we role it out to the other programmes. 

    Will be happy to share results and findings. 

    All the best


  • Weiwei Wu added an answer in Peeling:
    Why does the layer of PS peels off from the glass substrate after a drop casting?How can I avoid peeling?

    I tried to prepare some PS films using drop casting method. I dissolved 0.1g PS in 10ml THF, heated in a water bath and then drop casted it over a glass slide. The layer gets peel off from the substrate after drying it. Can anyone help me to avoid peel off problem in my coatings?

    Weiwei Wu · Technion - Israel Institute of Technology

    I think that it depend on the density of the solvent. If the density is too large and  let your PS film float on it's surface, the film will be peel off from the glass surface.

  • Suzie Kuan added an answer in 4-Aminobenzoic Acid:
    Does anyone synthesized diimine ligand from 4-aminobenzoic acid with 2,3-butanedione?

    I had try synthesized it with the addition of formic acid as catalyst and methanol as solvent according to a journal (attached)but yet i failed. What is the main problem I failed and does it have other method?

    Suzie Kuan · University Malaysia Sarawak


    Thank for your suggestion. I had synthesize the diimine using methyl-4-aminobenzoate and diacetyl in ethanol with a catalytic amount of acetic acid in the reaction . At the end i get a crystallize product and it is still methyl-4-aminobenzoate. My first attempt is to synthesize this diimine with ester group but since i failed to do so that why i wonder if i change the group to COOH according to the journal would success yet i still failed. 


    I would try to synthesize it without formic acid and give you feedback soon. Thank so much for the suggestion.  Dry condition as in dry solvent is it very important to get the product? If i not using dry solvent would it affect my result where is no reaction occur between the two reactant?

  • Sorb Yesudhas added an answer in Fullprof:
    How to rietveld XRD powder pattern by Fullprof or GSAS?

    I am studying in SrTiO3. However, I do not know how to Rietveld the crystal structure of the sample. Anybody can help me? Thanks.

    Sorb Yesudhas · Jawaharlal Nehru Centre for Advanced Scientific Research

    For Fullprof you need dat file (which is the raw data) in dat format. You have to create a pcr file, for that, you require structural information of the sample. For example, lattice parameter values, space group, X-ray wavelength and wyckoff positions. See the attached edpcr manual to create pcr file. After creating the pcr file, you have to adjust the scale factor, background and zero correction (instrumental). Then refine the lattice parameters, U, V, W and X to refine the widths, then assymmetric parameters, preferred orientation and finally wyckoff positions, thermal parameters and occupancy. This will come only through practice. Refine the above parameters together whenever required. Check the values of fitting parameters (should be less than 10) and goodness of fit (ideally it should be 1). Best of luck.

  • Ajeet Pratap Singh added an answer in Tamoxifen:
    What is the effective dose of tamoxifen to induce the recombination of CreERT2 in adult zebrafish?

    We want to induce recombination in the tail fin but we don´t have experience about tamoxifen treatments in adult zebrafish

    Ajeet Pratap Singh · Max Planck Institute for Developmental Biology

    Dear Martin,

    Sorry for overlooking that detail: we dissolve 4-OHT in absolute alcohol (Ethanol). This way, a 5mM stock solution is prepared and stored at -20C in small alliquots in a dark box. 4-OHT is light sensitive. Working concentration is 5microM. So just when I want to induce Cre, I add appropriate amount of the stock solution in fish rearing solution and kee the fish at 28C for about 1-2 hours.



  • Ram Nath Mishra added an answer in mRNA Expression:
    Can anyone suggest why I couldn't get a stable result when detecting ID1 mRNA expression by Q-PCR after BMP treatment?

    Recently, I tried to detect ID1 mRNA expression by Q-PCR after BMP treatment, However, I could not get stable result in every independent experiment (same treatment). There was no problem with RNA quality . So, why?

    Ram Nath Mishra · Independent Researcher

    You may try the following

    The Journal of Neuroscience, 25 August 2010, 30(34): 11426-11434; doi: 10.1523/JNEUROSCI.2570-10.2010                                                                                     Id Gene Regulation and Function in the Prosensory Domains of the Chicken Inner Ear: A Link between Bmp Signaling and Atoh1
    Andrés Kamaid

    Bone morphogenetic proteins (Bmps) regulate the expression of the proneural gene Atoh1 and the generation of hair cells in the developing inner ear. The present work explored the role of Inhibitor of Differentiation genes (Id1-3) in this process. The results show that Id genes are expressed in the prosensory domains of the otic vesicle, along with Bmp4 and Bmp7. Those domains exhibit high levels of the phosphorylated form of Bmp-responding R-Smads (P-Smad1,5,8), and of Bmp-dependent Smad transcriptional activity as shown by the BRE-tk-EGFP reporter. Increased Bmp signaling induces the expression of Id1-3 along with the inhibition of Atoh1. Conversely, the Bmp antagonist Noggin or the Bmp-receptor inhibitor Dorsomorphin elicit opposite effects, indicating that Bmp signaling is necessary for Id expression and Atoh1 regulation in the otocyst. The forced expression of Id3 is sufficient to reduce Atoh1 expression and to prevent the expression of hair cell differentiation markers. Together, these results suggest that Ids are part of the machinery that mediates the regulation of hair cell differentiation exerted by Bmps. In agreement with that, during hair cell differentiation Bmp4 expression, P-Smad1,5,8 levels and Id expression are downregulated from hair cells. However, Ids are also downregulated from the supporting cells which contrarily to hair cells exhibit high levels of Bmp4 expression, P-Smad1,5,8, and BRE-tk-EGFP activity, suggesting that in these cells Ids escape from Bmp/Smad signaling. The differential regulation of Ids in time and space may underlie the multiple functions of Bmp signaling during sensory organ development.

  • Bilal Succar added an answer in BIM:
    Can anyone help with statistics or materials regarding public client's interest in BIM?

    Apart from a new report of McGraw HIill Construction on BIM value for owners, I found it difficult to find information regarding public sector client's interest in BIM. Could you please give me some hints for that?

    It would be great if such information is investigated in Australia.

    Bilal Succar · University of Newcastle

    Hi Luan,

    Sure, feel free to contact me anytime.


  • Khaled Ahmed added an answer in Twitter:
    How can I collect data from Twitter for analysis?

    How can I collect data from Twitter for analysis?

    Khaled Ahmed · Cairo University

    you can work in two path static data set using 


    or dynamic real time data access to social media website API like Twitter API or Facebook API

    For analysis part you can use Google API, Alchamey API for NLP 

  • Should one consider the C-C Lennard jones interaction for a single layer graphene?

    Should one consider the C-C Lennard jones interaction for a single layer graphene?

    Sayyed Jalil Mahdizadeh · Ferdowsi University Of Mashhad

    How we can specify that the VdW interaction occur between Carbon atoms in a same chain when it is folded not neighboring Carbon atoms?

  • Govind Autee added an answer in Distribution Theory:
    Has anyone come across some case studies that address collaboration activities in the area of distribution logistics?

    It can be any form of collaboration in the area of distribution logistics. Thx.

    Govind Autee · Marathwada Institute of Technology

    Recent one seems to be "Design and scenario assessment for collaborative
    logistics and freight transport systems"


  • What is the best method for a life cycle impact assessment of products e.g environmental or food product like fish?

    Detailed methods, procedures including applications will be appreciated.

    Maria Iudicello · Euro-Mediterranean Institute of Science and Technology

    It must be understood first of all what the allocation criterion (economic or mass) of the impacts most suitable according to the type of product or process that must be considered.

  • Jan Willemson added an answer in Encryption:
    How can I implement elliptic curve encryption and decryption in java?

    Actually ,I am looking  the code for implementing elliptic curve cryptography(encryption and decryption) in java.

    Jan Willemson · Cybernetica

    I would also say that Bouncy Castle is the most widespread Java crypto library. It is definitely advisable to use standard libraries instead of writing your own. ECC is rather non-trivial to implement to avoid side channel attacks, nasty special cases etc.

  • Yang Hu added an answer in Laurates:
    How can I measure the concentration of sodium acetate, sodium laurate and sodium stearate?

    I want to measure the concentration of sodium acetate, sodium laurate and sodium stearate in solution, but they didn't have a characteristic absorption peaks in a UV spectrophotometer.

    Yang Hu · Universidad Autónoma de San Luis Potosí

    Thanks for the answers, I'm wonder is that possible to add some reagents into the solution to generate a new bond with sodium acetate, sodium laurate or sodium stearate. Then I can detect this new bond with a UV spectrophotometer

  • Juan Casado added an answer in Coprecipitation:
    Could anyone help me with products in coprecipitation of differente metal salts?

    I would like to synthesis Fe-based catalyst by coprecipitation. K and Mo may be added to the solution but I don´t know what oxides I´m going to obtain.

    In the precipation reaction an aqueous solution of NaOH are added dropwise up to reach pH 8, the solution is aged for 1 hour and the temperature of the whole process is 70ºC.

    Almost FeNO3 is converted into Fe2O3 but I´m not sure about what happens with KNO3. The K phase is important to calculate the metal atomic ratio of the final catalyst.

    Juan Casado · Autonomous University of Barcelona

    Assuming that, the answer you wanted is easy: follow the procedure of the cited reference...

  • Does anybody know why a mixture of zinc oxide and a silver nanoparticle solution changes its color from white to dark brown over time?

    The solution was mixed in a 1:1 weight ratio and has been kept in absence of light. Nanoparticles are suspended in ethylene glycol. Wasn't it supposed to be stable?

    Santa Chawla · National Physical Laboratory - India

    I agree with John Texter about oxidation of silver being the reason for change of colour.