50 research outputs found
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In situ formation of catalytically active graphene in ethylene photo-epoxidation.
Ethylene epoxidation is used to produce 2âĂâ107 ton per year of ethylene oxide, a major feedstock for commodity chemicals and plastics. While high pressures and temperatures are required for the reaction, plasmonic photoexcitation of the Ag catalyst enables epoxidation at near-ambient conditions. Here, we use surface-enhanced Raman scattering to monitor the plasmon excitation-assisted reaction on individual sites of a Ag nanoparticle catalyst. We uncover an unconventional mechanism, wherein the primary step is the photosynthesis of graphene on the Ag surface. Epoxidation of ethylene is then promoted by this photogenerated graphene. Density functional theory simulations point to edge defects on the graphene as the sites for epoxidation. Guided by this insight, we synthesize a composite graphene/Ag/α-Al2O3 catalyst, which accomplishes ethylene photo-epoxidation under ambient conditions at which the conventional Ag/α-Al2O3 catalyst shows negligible activity. Our finding of in situ photogeneration of catalytically active graphene may apply to other photocatalytic hydrocarbon transformations
An observational study to find association of serum vitamin B12 and folate level with neonatal weight at a tertiary care centre
Background: In developing countries like India, low birth weight is a challenging and important public health problem as it has adverse effect on growth and development of children. Vitamin B12 and folate are micronutrients essential for normal foetal growth and development. Maternal folate and B12 concentrations have been positively associated with birth weight. The aim of this study was to evaluate maternal folate and vitamin B12 status in pregnant women in third trimester of pregnancy and to find their relation with foetal birth weight.Methods: 171 pregnant women in their third trimester with live singleton pregnancy were included in the study. S. vitamin B12 and folate levels were measured and results were analysed.Results: Mean maternal vitamin B12 level in mothers with LBW infants was significantly lower than that of mothers of ABW infants (143.23±91.79 vs 188.8±109.64 respectively pâ€0.001) and mean maternal folate level in mothers with LBW infants was lower than that of mothers of ABW infants (8.46±8.94 vs 9.96±12.57 respectively p=0.054). There was a weak positive but statistically significant correlation between baby weight (kg) and S. vitamin B12 (rho=0.24, p=0.002) and S. folate (rho=0.17, p=0.029).Conclusions: The present study confirms that maternal low vitamin B12 level and low S. folate levels are associated with low birth weight so during antenatal visit women should be screened for vitamin B12 and folate deficiency and vitamin supplementation should be continued throughout the pregnancy
A conserved SNP variation in the pre-miR396c flanking region in Oryza sativa indica landraces correlates with mature miRNA abundance
Role of Herbal Medicine in Cardiovascular Activities
Herbal medicine has gained substantial attention for its potential role in supporting cardiovascular health. This chapter explores the intricate interplay between herbal compounds and cardiovascular activities, shedding light on their mechanisms of action and therapeutic applications. With a historical backdrop of traditional herbal medicine, the prevalence of cardiovascular diseases serves as a compelling backdrop for the investigation. The chapter delves into the multifaceted mechanisms by which herbal compounds influence the cardiovascular system. Notably, herbs exhibit vasodilatory effects, contributing to blood pressure regulation, and harbor potent antioxidant and anti-inflammatory properties that collectively mitigate oxidative stress and inflammation within the cardiovascular milieu. Furthermore, certain herbs intricately modulate lipid metabolism, holding promise in the management of dyslipidemia. A thorough analysis of well-known herbal treatments clarifies each one's unique contributions to cardiovascular health. Hawthorn is revealed to be the champion of heart health, and garlic demonstrates its mastery of cholesterol reduction. Ginkgo Biloba is notable for its capacity to improve circulation, and turmeric demonstrates powerful anti-inflammatory properties. The chapter also looks at herbal medicine's potential as an intervention for regulating fluid balance, arrhythmias, and hypertension. Examined is the potential for resveratrol-rich plants and green tea to protect against heart disease. Along with considerations for safety, interactions, and future study, the symbiotic relationship between stress reduction, adaptogenic herbs, and heart health is also discussed in this article. This chapter concludes with a thorough examination of the crucial part herbal medicine plays in cardiovascular health. The complex interaction between herbal substances and circulatory functions, from mechanisms of action to clinical applications, shows promise for a more integrative and holistic approach to cardiovascular car
Influence of Nutrient and Weed Management on Growth, Yield and Energetics of Maize
A field experiment entitled âInfluence of nutrient and weed management on growth, yield and bioenergetics of maize (Zea mays L.)â was conducted in agricultural research farm of Lovely Professional University, Punjab. The investigation was laid out in factorial randomized block design with three replications, aimed to study the impact of nutrient and weed management on growth attributes, yield attributes and bioenergetics of maize. The treatment consisted of three nutrient management treatments viz., T1 (100% N through Recommended dose of fertilizer), T2 (75% N through RDF and 25% N through vermicompost (P and K recommended doses)), T3 (75% N through RDF and 25% N through Farmyard manure) (recommended doses of P and K)); three weed management treatments, viz, W1 (control), W2 (Atrazine @1 kg a.i/ha + Tembotrione @110 g a.i/ha), W3 (Live mulching with cowpea). The results of the experiment revealed that among the nutrient management treatments, significantly higher growth attributes, yield attributes, energy output, energy efficiency index was observed with treatment T2 (75% N through RDF and 25% N through vermicompost) and the lowest was observed in treatment T1 (100% N through RDF), the pooled data suggested that yield was significantly highest in treatment combination T2W2 (75% N through RDF and 25% N through vermicompost along with Atrazine @1 kg a.i/ha + Tembotrione @110 g a.i/ha)
Plasmon-driven synthesis of individual metal@semiconductor core@shell nanoparticles
Most syntheses of advanced materials require accurate control of the operating temperature. Plasmon resonances in metal nanoparticles generate nanoscale temperature gradients at their surface that can be exploited to control the growth of functional nanomaterials, including bimetallic and core@shell particles. However, in typical ensemble plasmonic experiments these local gradients vanish due to collective heating effects. Here, we demonstrate how localized plasmonic photothermal effects can generate spatially confined nanoreactors by activating, controlling, and spectroscopically following the growth of individual metal@semiconductor core@shell nanoparticles. By tailoring the illumination geometry and the surrounding chemical environment, we demonstrate the conformal growth of semiconducting shells of CeO2, ZnO, and ZnS, around plasmonic nanoparticles of different morphologies. The shell growth rate scales with the nanoparticle temperature and the process is followed in situ via the inelastic light scattering of the growing nanoparticle. Plasmonic control of chemical reactions can lead to the synthesis of functional nanomaterials otherwise inaccessible with classical colloidal methods, with potential applications in nanolithography, catalysis, energy conversion, and photonic devices
Hidden duplicates: 10s or 100s of Indian trials, registered with ClinicalTrials.gov, have not been registered in India, as required by law.
BackgroundThis study's primary goal was based on the fact that since 15 June 2009 it has been mandatory to register regulatory trials running in India with Clinical Trials Registry-India (CTRI). Were all such trials, registered with ClinicalTrials.gov (CTG) after 2009, that included India as a location, also registered with CTRI? We first had to determine how to correctly identify a trial that was registered in both the registries, but that lacked the relevant secondary ID. Therefore the secondary goal of this study was to identify the best method to do this.MethodsWe used a control set of 1013 trials that cross-referenced a record in the other registry. We used two algorithms to-in a blinded fashion-identify CTRI matches for the 1013 CTG records. 80% of the predictions were correct. Using the same methodology, we identified matches for the CTG trials without known CTRI matches. We then used a logistic regression model to predict which of these matches were correct.Results(i) 3664 CTG records listed India as a location, but did not list any CTRI ID, and were not identified by any CTRI records either. (ii) The best single field to find a CTRI match for a CTG trial was the title field. (iii) Between 50 and 300 of 581 relevant CTG trials were not registered with CTRI.ConclusionsThis is the first study to use hidden duplicates to determine that the law on trial registration has been broken (in India). Similar studies need to be done for trials run in other countries
New Nano Architecture for SERS Applications
Silver silica gold sandwich nanoparticles were synthesized
by a multistep seeded growth process and were characterized by UVâvis
spectroscopy, transmission electron microscopy, and X-ray diffraction.
Gold islands allow passage of light through the crevices into the
silica layer, and the silver coreâsilica shell behaves like
a mirror, thus reflecting the light incident on it. These structures
facilitate light amplification due to mixing of light waves from the
multiple reflections. Sandwich nanoparticles show SERS enhancement
of âŒ10<sup>6</sup>. This enhancement factor is 6-fold larger
in magnitude than that of similar nanoparticles without the silver
core under identical experimental conditions
Cooperative Sybil Attack Detection in Privacy Preserved VANETs
Abstract In VANET, many attacks rely on having the attacker generate multiple identities to simulate multiple nodes, this is called the Sybil attack. By creating a large number of nameless identities, using them to gain large influence to the system. Utilizing social relationship among trajectories according to the similarity definition of two trajectories, Footprint can recognize and therefore dismiss "communities" of Sybil trajectories. But it is not sufficient for detection of Sybil attacks due to cooperation between the trajectories. In this paper, we propose a light-weight and scalable framework to detect Sybil attacks. To prevent a vehicle from abusing the pseudonyms to launch a Sybil attack, hashing is used. In our objective system, the Department of Motor Vehicle provides vehicles with a unique pool of pseudonyms, used for hiding a vehicle's unique identity. Vehicle pseudonym is stored in RSU. Now RSU evaluate hashed values and then determine pseudonyms of same pool to decrease Sybil attack our proposed schema mainly focus on detecting Sybil attack and provide security