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  • Adri de Klerk added an answer in Chalcones:
    Anyone can suggest a method for synthesizing chalcone grom vanillin and 4-chloroacetophenone?

    I've been working with vanillin and 4-chloroacetophenone to synthesize chalcone. I tried to stir and reflux it but no chalcone was formed but there is oily thing that didn't dissolve in aquadest or ethanol. I stir it for 5 minutes, 15 minutes, 30 minutes, 1 hour, 2 hours, and 1 day but the results were same. The reflux I did at 60°C results a chalcone but I think it were burned because the color was black. And I refluxed it at 35°C but there were no precipitate. Anyone can help me resolve this? Any alternatibe method I should use to synthesize chalcone from that precursors? Thank you

    Adri de Klerk

    Maybe it is necessary to protect the hydroxy of the vanillin first.

  • Kokkuvayil Sankaranarayanan Anil Kumar added an answer in Pedogenesis:
    Are acid soils truly chemically degraded?

    Acid soils develop under humid tropical (HT) climatic environment with a loss of some major nutrient elements, and thus the development of acidity in soils is considered to be a sign of chemical degradation. While estimating the area degraded by acidity, tropical Indian soils with strong (pH < 4.5) and moderate acidity (pH 4.5–5.5) only were considered.  About 6.98 m ha area is affected by soil acidity, which is about 9.4% of the total geographical area of India.

         Soils of HT climate in the states of Kerala, Goa, Karnataka, Tamil Nadu, Western Ghats and north-east hills (NEH) areas are strong to moderately acidic Alfisols, Ultisols and Mollisols   and their further weathering in HT climate would finally end up in kaolin dominated Ultisols with considerable amount of layer silicate minerals. Thus siliceous nature of the HT soils (especially the Ultisols of Kerala) is reflected in the SiO2:R2O3 (1.4–5.0) and SiO2:Al2O3 (1.8–6.0) ratios (Pal et al., 2014), suggesting an incomplete desilication process. The amount of SiO2 and its molar ratios are comparable with some of the Oxisols reported from Puerto Rico, Brazil, and other regions of the World. However, in the acidic Alfisols, Ultisols and Mollisols, the process of desilication no longer operates in present day conditions because the pH of the soils is well below the threshold of∼9.

         The OC rich Ultisols have less Al-saturation in surface horizons due to the downward movement of Al as organo-metal complexes or chelates, but have higher base saturation than the sub-surface horizons due to addition of alkaline and alkaline metal cations through litter fall, and there is no desilication and transformation of kaolin to gibbsite. In view of contemporary pedogenesis, it is difficult to reconcile that Ultisols (especially of Kerala hitherto considered to be of international reference for laterite) would ever be weathered to reach the Oxisols stage with time frame as often envisaged by the pedologists.

         Such OC rich acid soils are not kaolinitic as they are dominated by kaolin mineral (a mixed mineral) as their clay CEC is > 24 cmol (p+) kg-1 determined by BaCl2-TEA for total acidity plus bases by NH4OAc, pH7 method). These favourable chemical and mineralogical endowments help support the economically important forest and horticultural products, cereal crops, tea, coffee and spices. In view of the present successful and economically viable various land uses, it would not be prudent to class them as chemically degraded soils.

         The above knowledge is available through a recent review (attached) (Pal et al., 2014. Catena 121:260-278). But it is now made open for inviting valuable and useful comments/ suggestions of our esteemed colleagues all over the globe to accept or reject the finding that ‘acid soils are truly not degraded and never loses their usefulness’ even under adverse HT climatic conditions, and with suitable managements they show enough resilience in producing food and fibre for human sustenance.

    Kokkuvayil Sankaranarayanan Anil Kumar

    Ishall share the 2ND research papers which are part of the SQMS REPORT FOR SOUTH INDIA

  • Mudasser Habib asked a question in LPS:
    LPS extraction from Pasteurella multocida

    Hi everyone, Can anyone share a step-wise protocol of LPS extraction from Gram Negative bacteria.

  • G.E. Christidis added an answer in Mineralization:
    Is this Stockwork?

    I have recently visited a mineral occurrence with the following general characteristics:

    Pervasive argillic alteration in a subvolcanic intermediate rock, sulfide veinlets (partly oxidized), sulfide-bearing quartz veins, mineralized breccia, anomalies (or rather high amounts) of copper and gold, etc.

    As a whole, this occurrence seems to demonstrate the general features of an epithermal and /or a porphyry type of mineralization.

    An interesting feature to me was the presence of sets of parallel sulfide veinlets which in some cases, have been crosscut by other sets of parallel sulfide veinlets.

    I wonder, if this type of texture could be considered stockwork? Please see the attached pictures.

    I ask this, because some colleagues believe these are not stockwork because they are not randomly distributed in the rock.

    I appreciate any comment or experience in this regard.

    G.E. Christidis

    Dear Mr Nezafati

    The term stockwork describes a network of veinlets, usually (but not always) associated with alteration processes linked with mineralization. So yes your photos most probably belong to stockwork.

    Kind Regards

    George Christidis

  • Nazir Hussain added an answer in Aquaponics:
    Why do salt affected soils continue to pose potential threats to food security?

    Salt affected soils globally cover over 800 million ha (8-10% of of world land area), with a significant proportion of cultivated land is  salt affected . Such soils are characterized by salinity and sodicity of various demensions , the origin of which can be traced either geogenic or lithogenic or even combination of both. It is uncommon sight  to see , a soil once reclaimed is put to use for better crop production and added to the  main stream of  cultivated soils , though  still called as reclaimed soils. In this background , i put up following questions to my learned colleagues to contribute handsomely and benefit all of us:

    *Why dont we consider calcareous soils as a part of salt affected soils  ?

    * Why salts do not accumulate in grains or edible parts of plants ?. What are the mechanistic insights for such physiological events? 

    * Do we have sensors to  directly measure the salinity and sodicity in field? Or , alternatively , Is there any field diagnostic kit available for appraisal of salinity or sodicity right in the field?

    *Which type of reclamation is more sustainable from environment point of view?

    * How do you see the role(s) of salt tolerant microbes in reclamation and post-reclamation scenario of salt affected soils?  

    * What is the best method of artificial recharge of ground water?

    * What is the system of rice intensification , and what magnitude of success , it holds in salt affected soils?

    * How do you see the success of bio-saline agriculture ? Is saline aquaponics  potentially promising ?

    *How do you see the emerging issues on salinity and sodicity getting vitiated by consequences of climate change? How shall we reorient our objectives in this context?

    Thanks and regards 

    Nazir Hussain

    Yes, Dr. Kumar salinity is a predominant problem of arid and semi-arid regions. Causes of salinity do not exist in Humid regions unless salinity is produced by highly saline water irrigation from industry.

  • Artur Krężel added an answer in Hyaluronic Acid:
    Side reaction between thiol groups and MES Buffer?

    Hello everyone,

    I am working on the thiol functionalization of hyaluronic acid. Is there in general any side-reaction going on between MES-buffer and free thiol groups when i am dialysing my thiolated hyaluronic acid?

    Artur Krężel

    Hi Thomas. Indeed, the oxidation of your thiolated-HA might be a problem, especially during long dialysis at neutral pH. To decrease the efficiency of oxidation reaction you may decrease pH of your dialysis buffer, unless it is fine for your product. Rate of thiol oxidation decreases significantly when pH is slightly decreased. In general, pH buffer should be around one unit below pKa of the thiol. Another possibility to avoid the thiol oxidation is the incubation of your thiol-HA together with TCEP (2-(cerboxythyl)phosphine). It is great reducing agent, which in generally reduces all disulfide bonds. It can be use for most buffers including MES. Good luck!

  • Teun van Haaren asked a question in Education:
    Control variable non-significant after addition of related variable, can anyone explain to me the relationship? (mediator/spurious?)

    Can anyone explain to me why educational level of the parent is non-significant when educational level of the child is included in the analysis.

    Educational level of the parent significantly influences Y (attitude of the child), however after controlling for educational level of the child it does not influences Y anymore. Can anyone explaine me this relation?

  • Timur Shaimov asked a question in SAFE:
    How do you think: is it safe to reducing the interval between injections of ranibizumab to two weeks?

    Our recent study revealed AMD-related CNV recurrence during anti-VEGF therapy after 14 days of follow-up. It will be very interesting if we try to reduce interval between injections to two weeks. I didn't find evidence that it is unsafe.

    Dear colleagues, I want to hear you opinion...

  • Erdi Erdoğan added an answer in Action Research:
    Hi, can we use "action research" design without identification any problem situation? For example, to try new teaching method?

    Hi, can i use "action research" design without identification any problem situation? For example, to try new teaching method?. Can i apply action research design to new teaching method like experimental design? Thank you.

    Erdi Erdoğan

    Thanks for your all contributions,

    Best Regards ...

  • Research Student asked a question in Ethidium Bromide:
    PEI DNA polyplex low transfection rate?

    I'm transfecting breast cancer cells a gene of interest using PEI polyplex. Although my zeta potential of my PEI-dNA polyplex is good, and that  EtBr assay demonstrate lower fluorescence for PEI polyplex than PEG polyplex and control (just free DNA). The transfection rate is still very low for PEI polyplex (in the third graph) even though its suppose to demonstrate significantly higher transfection rates than PEG polyplex and control (free DNA). Also, my PEG polyplex shouldn't affect transfection rate, but I got a lower transfection rate (in the third graph) than even the control (free DNA). Transfection rates data are found using flow cytometry  to see the gene expression. 

  • Hossam Altaher added an answer in Water Sampling:
    Any simple method to measure the concentraions of heavy metals in a water sample ?

    i want to measure the concentration  of some heavy metals

    Hossam Altaher

    The simplest method is using Atomic Absorption Technique. But you have to have the lamb for each metal you want to detect. You can contact Dr. Tarek Akle in College of Science/Alex. He is expert in this area.

    Best luck in your research.

  • Mudasser Habib added an answer in Bacterial Cells:
    Which is the best way to extract lipopolysaccharides from bacterial cells?

    which is the best way to extract lipopolysaccharides from bacterial cells

    Mudasser Habib

    Hi Yaoqin Hong, Can you share a step-wise protocol of LPS extraction from Gram Negative bacteria. I am planning extraction from Pasteurella multocida.

  • Hazim Hashim Tahir added an answer in Critical Thinking:
    What Is critical thinking? Is it beneficial or harmful? How is it acquired?

    In many contexts critical thinking appears to be in very short supply. Whether in the field of politics, or education, or among adherents of one religion or the other people seem to swallow wholesale the view points of the establishment. Sometimes too one finds a magical and fatalistic approach to issues of life; suggesting that's the way it is meant to be and nothing can change it. In this background it is hard to imagine how there can be a better world. The question is: What is critical thinking? Is it beneficial or not? Why is it so scarce everywhere? How can it be transmitted and acquired in school,  out of school, as part of lifelong learning?

    Hazim Hashim Tahir

    Dear Colleagues,

    Good Day,

    "How is critical thinking beneficial in the decision-making process?

    • Firstly, critical thinking is a process as such the first benefit would be order, being able to address the "problem" intellectually as opposed to emotionally.
    • Critical thinking enables you to make scientific assessments weigh things, allot values, determine probabilities and the like
    • Critical thinking enable you to see the matter from different vantage points: in terms of logic, social acceptability, political viability, law, common sense, natural order, or 'this is my house' rules, or any other established norm set.
    • Critical thinking enables you to appreciate past performance, and to value experience
    • Critical thinking enable you to be more confident in your decision because it was well reasoned."....

    Please, see the link  

  • Mahmoud Fathi Maklad asked a question in Date Palm:
    How can increase and production the more number of male spath ( Bunches) in the male date palm trees ?

    How can increase and production the more number of male spathe ( Bunches) in the male date palm trees ?

  • Anroop Nair added an answer in In Vivo Experiments:
    Can anyone suggest how much DMSO can be given to mouse by oral gavage without causing any harm?

    I need to dissolve Vardenafil HCL in DMSO (Solbility 2mg/ml DMSO) in order to administer in a mouse (20mg) via oral gavage. That means I have to administer Vardenafil in almost 100 micro gram of DMSO by oral gavage. 

    I was wondering what is maximum safe dose of DMSO to administer in a mouse by oral gavage?

    I really appreciate any suggestion in this regard.


    Anroop Nair

    The oral LD50 for DMSO is ~7 mL/Kg, Means the safe dose is ~0.7 ml/kg for mouse. Consider diluting DMSO with water if possible.

  • Yoshinori Shiozawa added an answer in Tourism:
    Does anyone know of any survey data regarding post-earthquake effects of expats living in foreign countries, and also tourism businesses?

    I am teaching at the Prefectural University of Kumamoto in Kumamoto, Japan, the location of the most recent big earthquakes here. I am interested in conducting surveys in two areas: 1) foreign residents regarding English information during and after the earthquakes, and 2) tourism businesses regarding post-earthquake effects and how to revamp the tourism industry after an earthquake. I wondering if anyone has similar data or knows about similar studies. 

    Yoshinori Shiozawa

    Dear Jeffrey Stewart Morrow,

    your research is extremely helpful to the people damaged by natural disaster.  I remind of tsunami in Phuket, Thailand, 2004. I have no concrete information but Phuket is an internationally  famous tourist resort, you may find the history how it was recovered after Tsunami.


  • Dushyanth Kumar asked a question in ANSYS:
    What are mechanical properties of Resin LY556?

    I am analyzing a composite material by using ANSYS Mechanical APDL so as to provide the material properties in the APDL i need them

  • Tihomir Nikolaev Tsanov added an answer in Polymerization:
    Does the depletion interaction just exist between particles and polymer ?

    the depletion interaction has been proved exist in colloidal system, I am thinking whether it exist between different polymer or the same polymer with different molecular weight ?

    Tihomir Nikolaev Tsanov

    I worked with P E O many years ago. What is the ratio (%) of low and high molecular weight polymers? Moreover, both mixing itself and interaction processes depend on the solutions' concentrations, at least. The temperature also affects them. Most probably, your low MW P E O should not be compacted. Have success and best wishes! 

  • Anicet Beauvais added an answer in Mineralogy:
    Does depth control the nature of mineral alterations?

    Weathering and alteration are usually near surface phenomena.

    I am observing rocks collected from>100 meters depth...which are highly altered.

    what kind of alterations are prominent at greater depths?

    what are the factors the govern this kind of alterations?

    Is it structure/ mineralogy or something else?

    Anicet Beauvais

     Asoori, If you refer to supergene weathering, may be you know the manganese ore deposit of Sandur in Peninsular India. We recently show that supergene cryptomelane as old as 35 Ma crystallized between 100 and 140 m depth. Also peridotite of New Caledonia are deeply weathered with occurrences of Ni rich lizzardite, talc, Ni-smectite and goethite among others minerals at depths > 100 m (Co rich Mn oxyhydroxides like lithiophorite or asbolan also crystallize at such depths). Another point is that meteoric waters warm up when moving down, leading to specific minerals to form, which do not result necessarily from pure hydrothermalism but rather from exothermic water-rocks interactions. Best wishes, Anicet

  • Harald G. Dill added an answer in Volcanic Geomorphology:
    What features help discern pyroclastic flow deposits from surge deposits?

    I have attached a few pictures below, wondering if people might offer their interpretation about some rhyolite tuffs in central Washington. I'm interpreting the first two photos from section of surge deposits, and the last two photos from a section of block and ash flow deposits. The tuff section in the last two photos contains large 5-7 m vitric blocks, presumably transported from near the source? Any feedback, or start of dialogue much appreciated!

    + 3 more attachments

    Harald G. Dill

    Dear Mrs. Patridge,

    If you are a novice in pyroclastic deposits but have some knowledge in sedimentology apply what you have learnt for arenaceous and fluvial deposits to what you suspect of being  a surge deposit. Pyroclastic flow deposits are more difficult to interpret due to the complex mode of transport and the welding process which may be occur in these deposits also known as ignimbrites and nuees ardentes. For a more detailed interpretation I refer to the textbook: Fisher,R.V., Schmincke,H.-U. 1984. Pyroclastic Rocks. Springer-Verlag, 196 pp which is still worth to be consulted in a case like that.

    You may also download the paper "DILL, H.G., TECHMER, A., BOTZ, R., DOHRMANN, R. and   KAUFHOLD, S. (2012) Hypogene and supergene alteration of  the zeolite-bearing pyroclastic deposits at  Tell Rimah, Jordan, and rift-related processes along the Dead-Sea-Transform Fault System during the Quaternary.- Journal of Volcanology and Geothermal Research,  239-240: 49-68.

    It may provide you with some kind of a guideline how to deal with such pyroclastic deposits (of economic interest) in the field, from the bird’s eye view and the laboratory.

    As far as the interpretation of your images are concerned I concur with Mr. Lages, even if I am a bit reluctant to hand down remote-controlled diagnosis of this kind.

    I wish you much success


  • Stelios Ioannou added an answer in Power Supply:
    How to connect two programmable power supply (Tektronix PSW 4005) in series for using it above the upper voltage protection limit??

    I want to apply a constant current across the electrolyte solution of HF and acetic acid. The programmable power supply has the limit of 30V, 5A. When I apply the current above 1A, the voltage reaches above the voltage protection limit and hence the voltage level is clamped to 30V and the current become less than the desired limit, not under the constant mode. What is the solution to use the power supply for this type of problem?? Is it possible by using series connection of similar power supplies??

    Stelios Ioannou

    It sounds like your power supply is limited to an constant output power of 30 Watts.

    This implies the following:

    At voltage of 30v the maximum current will be 1A

    At voltage of 15v the maximum current will be 2A

    At voltage of 6v the maximum current will be 5A

     From what I know, you can NOT use power supplies in series. The solution is to buy a higher Power Rated power supply. For example, for 5A at 30V it implies a rated power of 150W.

    You can also look into custom made circuit solutions using Power Transistors.

    Let me know if you have more questions.

  • Reza Mahdavi added an answer in Poultry:
    Amino acid transporters?

    Dear researchers,

    Does anyone have any reference or an article (review) about the types of intestinal amino acid transporter and its actions in poultry other than article entitled absorption of amino acids and peptides by C. R. Krehbiel and J. C. Matthews).


    Reza Mahdavi


    This article that professor Wong sent me very useful for those who wants to know more about amino acid  transporter.

  • Dr. A. K. Malik added an answer in Supply Chain:
    Is there a framework of supply chain costing?

    is there a defined framework for the application of strategic cost management in the supply chain 

    Dr. A. K. Malik

    see the attachment for frame work of scm.

  • Allahbakhsh Joiya added an answer in Transgenic Plants:
    Inconsistent transgene expression among transgenic lines under a constitutive promoter in plants?

    I transformed a 6His tag fusion gene driven by  AtUBQ10 promoter and expressed it in Arabidopsis. In T1 transgenic plants, first I used genotying to confirm they were real transgenic plants; In order to obtained trangenic lines with a decent transgene expression for study, I used western blotting against 6His antibody to check protein expression of this gene among T1 transgenic plants. Surprisingly, only ~10% transgenic lines showed strong protein expressions, the rest showed weak expressions. Is it often the case for you?

    What could be the reason for the inconsistency of expressions among individuals??

    Are there other genes that do not express when under a constitutive promoter?

    Thank you!

    Allahbakhsh Joiya

    Hii Yuan, Many factors are worth considering here. The expression of introduced gene can be temporally as well as spatially regulated. Finding a stable transgene (with same bahaviour over generations) is not that easy. As we know that every individual plant carries a different transformation event, so its behaviour will be different. As Prof. Yuan-Yue described, you need to find out copy number of the lines, take care of this factor. Also remember 35S has also been reported for differentially regulation. Please see the litearute, same might be case with uniquitin. You may need to find homozygous line over a cycle of selections (+/+, +/- and -/-) in order to obtain a stable transgene. Good luck

  • Surabhi Jain asked a question in Microorganisms:
    I want to grow my microorganisms in low pH range. is there any problem if I mix HCL IN NUTRIENT broth?

    when i am mixing HCL to make pH 3, the color of nutrient is changing.

  • Magdy Eisa Saafan added an answer in Auditory Hallucinations:
    Are there any distinctions between auditory hallucinations and tinnitus?

    Because, definition they mean the same, so is quoted in Otolaryngol Clin N Am 36 (2003) 249–266.

    Magdy Eisa Saafan

    Tinnitus is used to describe noise in the ear or head. May be pulsitile sound synchronised with heart beats, may be machinary windy or roaring soind

    auditory hallucination is commonly used by psychiatrists to descibe false percoption of non existing sounds. Comonly formed sounds likie speach words and usually indicates psychological disorders

  • Budiatman Satiawihardja added an answer in Fermentation Biotechnology:
    How do we calculate hydrogen yield using TSVS in the fermentation process?
    I am working on hydrogen fermentation from a plant. I have obtained the accumulated hydrogen from GC measurements and daily gas sample collection, but now would like to calculate the hydrogen yield using TSVS or TOC. So, if anyone could help, I would be grateful.
    Budiatman Satiawihardja

    Dear Mishma,

    I had got an experience doing carbon balance in lysine production process using continuous culture system. You should create an equation for the carbon balance in which input = output. Any component carrying carbon atoms either at input or output should be identified, then written in the equation total input = total output. The carbon fractions in each compound containing carbon should be calculated, both in the liquid phase and in the gas phase, then check whether total carbon fractions of input = total carbon fractions of output. That's all.

    Best regards,

    Budiatman Satiawihardja

  • Somayyeh Asgari added an answer in Graphene:
    How do you get accurate results with HFSS for graphene simulation?
    I am trying to simulate a simple graphene printed dipole antenna with HFSS. Because of frequency dependent conductivity of the graphene, the antenna is very small in comparison to lambda/2 metallic dipole and it should operate with surface plasmon TM mode. I use lumped port excitation. The problem is that I can't find the resonance of the antenna. Which challenge with similar designs should be taken into account ? What do you recommend to check and might be wrong to get accurate results?
    Somayyeh Asgari

    You should choose an electric dipole point source and its axis should be perpendicular to the graphene layer. Maybe, if you shrink your mesh size, you will get better results... In each direction, your mesh size should be 0.1 of the dimansion

    Why don't you simulate your structure with lumerical or comsol?

  • Dr. A. K. Malik added an answer in Nonlinear Optimization:
    Utility Function ? (please introduce some utility functions) ?

    I'm going to use an utility function in my nonlinear optimization model. (for asset allocation problem)

    It can be logarithmic function like :  log(cTx) (C transpose X)

    Please introduce me some other popular utility functions except log.

    Dr. A. K. Malik

    See the attachments for utility functions.

  • Matthieu Cristelli added an answer in Behavioural Economics:
    How can we quantify investor sentiments in equity markets ?

    I am working on a project involving stock price estimation, so I want investor sentiments or behavioral bias to be an independent factor, impacting stock price movement. So, are there any means by which I can quantify this variable ?

    Matthieu Cristelli

    Have a look at this paper as well https://scholar.google.com/citations?view_op=view_citation&hl=en&user=fnFoz8gAAAAJ&cstart=160&sortby=pubdate&citation_for_view=fnFoz8gAAAAJ:kNdYIx-mwKoC and previous work by Misako Takayasu. Hope it can help.