Application of Fluorescent CQDs for Enhancing the Performance of Solar Cells and WLEDs

Carbon quantum dots (CQDs) are emerging as promising materials for applications like flexible or transparent solar cell, white light emitting diodes (WLEDs), etc. due to their low cost, eco-friendliness, substantial absorption coefficient, wide absorption spectrum, tuneable optical properties, good charge transfer/separation ability, good quantum yield and large two-photon absorption cross-section. They have been employed in solar cells as active absorbing layers, electron acceptors/donors, electron sinks, electron transporting layers (ETL), hole transporting layers (HTLs), dopants, and interlayer spacing. Consequently, such solar cells have exhibited enhanced performance. In contrast to commercial rare-earth phosphors and traditional semiconductor quantum dots (SQDs) (usually toxic), CQDs exhibit wide range of emission characteristics [full width half maxima (FWHM) > 80 nm]. Interestingly, the emission characteristics of these nanomaterials are tuneable which makes them suitable for WLEDs applications. Red-CQDs are gaining importance as they are required to realize the warm WLEDs. Though a lot of work has been done to modulate the properties of CQDs in order to enhance the performance of solar cells and WLEDs, there are immense possibilities to further exploit the potential of CQDs in these applications

Phenylalanine-Rich Peptides Potently Bind ESAT6, a Virulence Determinant of Mycobacterium tuberculosis, and Concurrently Affect the Pathogen's Growth

BACKGROUND:The secretory proteins of Mycobacterium tuberculosis (M. tuberculosis) have been known to be involved in the virulence, pathogenesis as well as proliferation of the pathogen. Among this set, many proteins have been hypothesized to play a critical role at the genesis of the onset of infection, the primary site of which is invariably the human lung. METHODOLOGY/PRINCIPAL FINDINGS:During our efforts to isolate potential binding partners of key secretory proteins of M. tuberculosis from a human lung protein library, we isolated peptides that strongly bound the virulence determinant protein Esat6. All peptides were less than fifty amino acids in length and the binding was confirmed by in vivo as well as in vitro studies. Curiously, we found all three binders to be unusually rich in phenylalanine, with one of the three peptides a short fragment of the human cytochrome c oxidase-3 (Cox-3). The most accessible of the three binders, named Hcl1, was shown also to bind to the Mycobacterium smegmatis (M. smegmatis) Esat6 homologue. Expression of hcl1 in M. tuberculosis H37Rv led to considerable reduction in growth. Microarray analysis showed that Hcl1 affects a host of key cellular pathways in M. tuberculosis. In a macrophage infection model, the sets expressing hcl1 were shown to clear off M. tuberculosis in much greater numbers than those infected macrophages wherein the M. tuberculosis was not expressing the peptide. Transmission electron microscopy studies of hcl1 expressing M. tuberculosis showed prominent expulsion of cellular material into the matrix, hinting at cell wall damage. CONCLUSIONS/SIGNIFICANCE:While the debilitating effects of Hcl1 on M. tuberculosis are unrelated and not because of the peptide's binding to Esat6-as the latter is not an essential protein of M. tuberculosis-nonetheless, further studies with this peptide, as well as a closer inspection of the microarray data may shed important light on the suitability of such small phenylalanine-rich peptides as potential drug-like molecules against this pathogen

Dengue Virus Serotypes 1 and 2 Responsible for Major Dengue Outbreaks in Nepal: Clinical, Laboratory, and Epidemiological Features

Dengue virus (DENV) is expanding toward previously nonendemic areas. DENV has recently been introduced in Nepal with limited information. We report the clinical features and serotype distribution of DENV in Nepal during the 2010 outbreaks. A total of 1,215 clinical dengue cases at two major hospitals of central and western Nepal were investigated. Demographic, clinical, and laboratory parameters were recorded. Serum specimens were tested for DENV by IgM/IgG enzyme-linked immunosorbent assays (ELISAs) and reverse transcription polymerase chain reaction (RT-PCR). We confirmed DENV infection in 403 (33%) patients from 12 districts with an estimated case fatality rate of 1.5%. DENV infection was more common in adults (87%) and urban settings (74%). We detected all four serotypes but DENV-1 and -2 were mainly responsible for major outbreaks (92%). Overall, 60% of all DENV infections were secondary and 17% were severe dengue; both being more frequent among the DENV-2 infections. Rash, bleeding, abdominal pain, hepatomegaly, elevated liver enzymes, and thrombocytopenia were significantly more common in severe dengue compared with nonsevere infections. We also confirmed the expansion of dengue to hill urban areas (DENV-1 and -2), including the capital Kathmandu (altitude, 1,300 m) though > 90% cases were from southern plains. Differential clinical and laboratory features probably help in clinical decisions. Multiple serotypes circulation and elevated secondary infections pose potential risk of severe outbreaks and deaths in the future. Therefore, a country with recent dengue introduction, like Nepal, urgently requires a systematic surveillance and appropriate control measures in place to respond to any disastrous outbreaks

Search of an equation of state for nanomaterials

642-650An effort is made to search a suitable equation of state (EOS) model for the nanomaterials. Six EOS models based on different physical origins viz. Brich-Murnaghan model, Murnaghan model, Kumar model, Vinet model, Freund and Ignalls model and Tallon model are used to study the compression behaviour of thirty one nanomaterials. The results are compared with the available experimental data. It is concluded that the Murnaghan model performs well for the materials considered in the present paper for the pressure ranges considered in the experimental studies of these materials. It is also discussed that the Murnaghan model may be obtained using different concepts

Facial pain - An enigma

It is well known, pain is the most common reason why people seek healthcare. Pain is a personal, unpleasant sensory experience reflecting the physiologic, biologic, genetic and psychosocial factors. Some orofacial pain conditions are very complex and perplexing. With regular diagnosis, misdiagnosis and medical interventions which unfortunately later prove to be deceptive, such atypical orofacial pains are seemingly untreatable and puts the physician in a fix. In this article various facets of orofacial pain, peripheral mechanism, central sensitization, the absurd referral patterns and altered peripheral receptive field of chronic odontogenic pain are discussed with ample clinical evidences implicating the fact that all trigeminal pains are not trigeminal neuralgic pains. Treatment by classic drugs for trigeminal neuralgia in such cases cause more harm than any benefit to the patients. This article depicts cases showing how unremitting pain in trigeminally mediated areas secondary to dental causes is a unique challenge for the doctor and patient alike

Facial pain - An enigma

It is well known, pain is the most common reason why people seek healthcare. Pain is a personal, unpleasant sensory experience reflecting the physiologic, biologic, genetic and psychosocial factors. Some orofacial pain conditions are very complex and perplexing. With regular diagnosis, misdiagnosis and medical interventions which unfortunately later prove to be deceptive, such atypical orofacial pains are seemingly untreatable and puts the physician in a fix. In this article various facets of orofacial pain, peripheral mechanism, central sensitization, the absurd referral patterns and altered peripheral receptive field of chronic odontogenic pain are discussed with ample clinical evidences implicating the fact that all trigeminal pains are not trigeminal neuralgic pains. Treatment by classic drugs for trigeminal neuralgia in such cases cause more harm than any benefit to the patients. This article depicts cases showing how unremitting pain in trigeminally mediated areas secondary to dental causes is a unique challenge for the doctor and patient alike

Metabolomics and its role in plant pathology

Metabolomics is one of the most eminent and newly emerging omic sciences. It is a powerful tool to study metabolic changes that occur in an organism. Plants produce a wide range of metabolites and the study of these metabolites can answer a number of questions that arise in the minds of researchers. Change in the metabolites is the most important feature in a genetically modified plant or plant interactions with pests, pathogens and the environment. Plant pathogen interactions are amongst the most biochemically complex mechanisms and pose a great challenge in front of plant pathologists; metabolomics not only play a great role in deciphering these complex interactions but also the study of certain defence-related metabolic changes can be utilized in a number of ways to protect the plant from the harmful pathogens. The science of metabolomics utilizes a number of techniques to study the wide variety of metabolites. This review will give a brief about the various techniques used in metabolomics and how some of these techniques have been successfully utilized in the field of plant pathology.La métabolomique est l’une des sciences omiques les plus éminentes et les plus récentes. Elle constitue un outil puissant pour étudier les changements métaboliques qui se produisent dans un organisme. Les plantes produisent un large éventail de métabolites et l’étude de ces métabolites peut répondre à un certain nombre de questions que se posent les chercheurs. La modification des métabolites est le caractère déterminant dans une plante génétiquement modifiée ou dans les interactions de la plante avec les ravageurs, les pathogènes et l’environnement. Les interactions entre les plantes et les pathogènes sont parmi les mécanismes les plus complexes sur le plan biochimique et constituent un grand défi pour les phytopathologistes; la métabolomique joue non seulement un rôle important dans le décryptage de ces interactions complexes, mais l’étude de certains changements métaboliques liés à la défense peut être utilisée de plusieurs façons pour protéger la plante contre les pathogènes nuisibles. La science de la métabolomique utilise un certain nombre de techniques pour étudier une grande variété de métabolites. Cette revue donne un aperçu des différentes techniques utilisées en métabolomique et comment certaines de ces techniques ont été utilisées avec succès dans le domaine de la phytopathologie

Evaluation of Solanum lycopersicum L. genotypes for high temperature stress tolerance employing temperature induction response technique

680-689Solanum lycopersicum L., an important vegetable crop (Tomato) in most regions of the world, is affected by high temperature stress at various stages of its growth. Likely increase in periodicity of high temperature episodes under climate change conditions would further affect the tomato production. To sustain productivity and yields under climate change situations, there is an urgent need to develop suitable cultivars as an adaptation strategy. For this endeavour, identification of high temperature tolerant lines for crop improvement is a prerequisite. Hence in the present study, temperature induction response (TIR) technique was employed to evaluate thermotolerance in 52 tomato genotypes. Two day old seedlings were subjected to an initial induction treatment i.e., gradual temperature increase from 33-43°C for 3 h followed by 50°C for 3 h as challenging temperature. Wide variability was seen for seedling survival and vigour. In genotypes IIHR-2202, IIHR-2836 and IIHR-2841 seedling survival was as high as 90%, while H-329, H-371, IIHR-2745 and H-335 showed least reduction in growth and also had better seedling vigour index. Of the 52 genotypes, 21 were identified as tolerant, 12 moderately tolerant and 19 susceptible. This TIR technique is simple, quick and less expensive than whole plant screening. Hence, it could be used by plant physiologists and plant breeders for screening seedlings at an early stage in the phenotyping and crop improvement programmes