75 research outputs found

    Observations on the monsoon prawn fishery in Kerala

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    The ban on trawling in Kerala from June 15th to July 30th coincides with the southwest monsoon. During the period fishermen venture into the sea with their traditional/motorised crafts and gears such as thermocol boats (Alapuzha) and Thanguvallom (Ernakulam and Thrissur). The latter is operated with outboard engines and operate up to 8 km from the shore. The thermocol boats fish very near the shore (up to 3 km). The gear operated are ring seines or thangu vala and gill nets. The unique phenomenon in the monsoon season known as mud-bank or ‘chakara’ is characterised by calm areas close to the shore

    Adhesion of alumina surfaces through confined water layers containing various molecules

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    When two surfaces confine water layers between them at the nanoscale, the behaviour of these confined water molecules can deviate significantly from the behaviour of bulk water and it could reflect on the adhesion of such surfaces. Thus, the aim of this study is to assess the role of confined water layers on the adhesion of hydrophilic surfaces and how sensitive this adhesion is to the presence of contaminants. Our methodology used under water AFM force measurements with an alumina sputtered sphere-tipped cantilever and a flat alumina single crystal, then added fractions of ethanol, dimethylformamide, formamide, trimethylamine, and trehalose to water, as contaminants. Such solutions were designed to illuminate the influences of dielectric constant, molecular size, refractive index and number of hydrogen bonds from donors and acceptors of solutes to water. Apart from very dilute solutions of dimethylformamide, all solutions decreased the ability of confined water to give adhesion of the alumina surfaces. The predicted theoretical contribution of van der Waals and electrostatic forces was not observed when the contaminants distorted the way water organizes itself in confinement. The conclusion was that adhesion was sensitive mostly to hydrogen bonding network within water layers confined by the hydrophilic alumina surfaces

    Experimental search for super and hyper heavy nuclei at cyclotron Institute Texas A&M University

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    The question "How heavy can an atomic nucleus be?" is a fundamental problem in nuclear physics. The possible existence of island(s) of stable super-heavy nuclei has been an inspiring problem in heavy ion physics for almost four decades. This paper is focused on the experimental search of Super/Hyper Heavy Elements (SHE/HHE) conducted at the Cyclotron Institute, Texas A&M University. A novel experimental idea and experimental set up introduced for this research will be presented

    Methylation screening of the TGFBI promoter in human lung and prostate cancer by methylation-specific PCR

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    <p>Abstract</p> <p>Background</p> <p>Hypermethylation of the <it>TGFBI </it>promoter has been shown to correlate with decreased expression of this gene in human tumor cell lines. In this study, we optimized a methylation-specific polymerase chain reaction (MSP) method and investigated the methylation status of the <it>TGFBI </it>promoter in human lung and prostate cancer specimens.</p> <p>Methods</p> <p>Methylation-specific primers were designed based on the methylation profiles of the <it>TGFBI </it>promoter in human tumor cell lines, and MSP conditions were optimized for accurate and efficient amplification. Genomic DNA was isolated from lung tumors and prostatectomy tissues of prostate cancer patients, bisulfite-converted, and analyzed by MSP.</p> <p>Results</p> <p>Among 50 lung cancer samples, 44.0% (22/50) harbored methylated CpG sites in the <it>TGFBI </it>promoter. An analysis correlating gene methylation status with clinicopathological cancer features revealed that dense methylation of the <it>TGFBI </it>promoter was associated with a metastatic phenotype, with 42.9% (6/14) of metastatic lung cancer samples demonstrating dense methylation vs. only 5.6% (2/36) of primary lung cancer samples (<it>p </it>< 0.05). Similar to these lung cancer results, 82.0% (41/50) of prostate cancer samples harbored methylated CpG sites in the <it>TGFBI </it>promoter, and dense methylation of the promoter was present in 38.9% (7/18) of prostate cancer samples with the feature of locoregional invasiveness vs. only 19.4% (6/31) of prostate cancer samples without locoregional invasiveness (<it>p </it>< 0.05). Furthermore, promoter hypermethylation correlated with highly reduced expression of the <it>TGFBI </it>gene in human lung and prostate tumor cell lines.</p> <p>Conclusion</p> <p>We successfully optimized a MSP method for the precise and efficient screening of <it>TGFBI </it>promoter methylation status. Dense methylation of the <it>TGFBI </it>promoter correlated with the extent of <it>TGFBI </it>gene silencing in tumor cell lines and was related to invasiveness of prostate tumors and metastatic status of lung cancer tumors. Thus, <it>TGFBI </it>promoter methylation can be used as a potential prognostic marker for invasiveness and metastasis in prostate and lung cancer patients, respectively.</p

    Facile route to conformal hydrotalcite coatings over complex architectures:a hierarchically ordered nanoporous base catalyst for FAME production

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    An alkali- and nitrate-free hydrotalcite coating has been grafted onto the surface of a hierarchically ordered macroporous-mesoporous SBA-15 template via stepwise growth of conformal alumina adlayers and their subsequent reaction with magnesium methoxide. The resulting low dimensional hydrotalcite crystallites exhibit excellent per site activity for the base catalysed transesterification of glyceryl triolein with methanol for FAME production

    Technical Issues Related to the Use of Fly Ash and Slag During Late-Fall (Low Temperature) Construction Season

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    The potential for scaling of concrete pavement containing fly ash is one of the durability concerns which imposes restrictions on the use of fly ash in paving applications in Indiana during the period of low temperatures (e.g., the late fall construction season). These restrictions increase the cost of paving projects, and occasionally, results in seasonal cement shortages. The objective of this study was to develop a better understanding of the scaling mechanism through a series of laboratory tests that focused on the role of material properties and length and temperature of curing in controlling scaling. Additionally, an attempt was made to simulate field conditions in the laboratory and to relate these results with performance of concrete pavement. Concrete mixtures were prepared with two different slumps using material combinations that had previously shown high susceptibility to scaling. These mixtures were used to study the influence of the length of moist curing and drying periods on scaling of fly ash concrete, exposed to normal and low early-age temperatures. The scaling studies were supplemented with microstructural and chloride ion penetration tests to assist in the interpretation of these results. To study the influence of temperature of curing, fresh properties and scaling were measured for low temperature cast and cured specimens. To understand the behavior of actual pavement constructed in late fall, large size insulated specimens were prepared at low temperature in the laboratory, for scaling and other relevant studies. In relating laboratory scaling results to field performance, wide differences have been observed indicating severity of laboratory scaling test (ASTM C672). Extensive literature review and telephone survey was conducted to collect information regarding field scaling performance of pavements with supplementary cementitious materials. Based on above information and further laboratory studies, five main parameters are suggested to resolve the apparent discrepancies between laboratory results and field observations. Simultaneously, a risk analysis approach was used to determine the probability of scaling in Indiana. It was determined that probability of initiation of scaling for a typical pavement is only 0.5%. It was further concluded that, for replacement levels 20-25%, fly ash can be used to produce scaling-resistant concrete during late fall paving season for climatic conditions similar to that encountered in Indiana
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