121 research outputs found

    Distribution, biomonitoring and conservation studies of pyrenocarpous lichens in India

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    India is represented by the occurrence of the 382 species of pyrenocarpous lichens belonging to 49 genera and 12 families. Pyrenulaceae with six genera and 102 species is dominant family followed by Porinaceae with six genera and 88 species. Pyrenocarpous lichen genus Pyrenula with 82 species exhibits its dominance over Porina with 72 speĀ­cies. A total 25 pyrenocarpous genera are represented by a one or two species. The Western Ghats region exhibit rich diversity of pyrenocarpous lichens in India. The pyrenocarpous lichens commonly grows on smooth bark of trees or sometimes on rock, soil or leaves in tropical and temperate region of the country

    Development of ETD Repository at IITK Library using DSpace

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    Establishing an ETD repository at any organization having large volume of these is really a challenging task. As the Indian Institute of Technology Kanpur had started its research programs from 1963 onwards, we have over 9000 of M.Tech and Ph. D theses in different areas of Science, Engineering, and Humanities & Social Sciences. We have completed the digitization of all submitted theses. Our ETD powered by DSpace with more advanced features like crosscollection search, linking to referred IITK theses, user friendly design and customized work flow for different modes of submission of theses to ETD etc.. In this paper, we clearly explain and share the experiences we have gained from the digitization to accessing ETD, and the challenges we faced, enhancements we incorporated with special emphasis on technical developments, and the lessons we have learnt during the various stages of development of our project for ETD

    Chalcogen Assisted Enhanced Atomic Orbital Interaction at TMDs - Metal Interface & Chalcogen Passivation of TMD Channel For Overall Performance Boost of 2D TMD FETs

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    Metal-semiconductor interface is a bottleneck for efficient transport of charge carriers through Transition Metal Dichalcogenide (TMD) based field-effect transistors (FETs). Injection of charge carriers across such interfaces is mostly limited by Schottky barrier at the contacts which must be reduced to achieve highly efficient contacts for carrier injection into the channel. Here we introduce a universal approach involving dry chemistry to enhance atomic orbital interaction between various TMDs (MoS2, WS2, MoSe2 and WSe2) & metal contacts has been experimentally demonstrated. Quantum chemistry between TMDs, Chalcogens and metals has been explored using detailed atomistic (DFT & NEGF) simulations, which is then verified using Raman, PL and XPS investigations. Atomistic investigations revealed lower contact resistance due to enhanced orbital interaction and unique physics of charge sharing between constituent atoms in TMDs with introduced Chalcogen atoms which is subsequently validated through experiments. Besides contact engineering, which lowered contact resistance by 72, 86, 1.8, 13 times in MoS2, WS2, MoSe2 and WSe2 respectively, a novel approach to cure / passivate dangling bonds present at the 2D TMD channel surface has been demonstrated. While the contact engineering improved the ON-state performance (ION, gm, mobility and RON) of 2D TMD FETs by orders of magnitude, Chalcogen based channel passivation was found to improve gate control (IOFF, SS, & VTH) significantly. This resulted in an overall performance boost. The engineered TMD FETs were shown to have performance on par with best reported till date

    Role of Serine/Threonine Kinase 11 (STK11) or liver kinase B1 (LKB1) Gene in Peutz-Jeghers Syndrome

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    Peutz-Jeghers syndrome (PJS) is a well-described inherited syndrome, characterized by the development of gastrointestinal polyps and characteristic mucocutaneous freckling. PJS is an autosomal prevailing disease, due to genetic mutation on chromosome 19p, manifested by restricted mucocutaneous melanosis in association with gastrointestinal (GI) polyposis. The gene for PJS has recently been shown to be a serine/threonine kinase, known as LKB1 or STK11, which maps to chromosome subband 19p13.3. This gene has a putative coding region of 1302 bp, divided into nine exons, and acts as a tumor suppressor in the hamartomatous polyps of PJS patients and in the other neoplasms that develop in PJS patients. It is probable that these neoplasms develop from hamartomas, but it remains possible that the LKB1 or STK11 locus plays a role in a different genetic pathway of tumor growth in the cancers of PJS patients. This article focuses on the role of LKB1 or STK11 gene expression in PJS and related cancers

    An overview of vaccine development for COVID-19

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    The COVID-19 pandemic continues to endanger world health and the economy. The causativeĀ SARS-CoV-2 coronavirus has a unique replication system. The end point of the COVID-19 pandemic is either herd immunity or widespread availability of an effective vaccine. Multiple candidate vaccines - peptide, virus-like particle, viral vectors (replicating and nonreplicating), nucleic acids (DNA or RNA), live attenuated virus, recombinant designed proteinsĀ and inactivated virus - are presently under various stages of expansion, andĀ aĀ small number of vaccine candidates have progressed into clinical phases. At the time of writing, three major pharmaceutical companies, namely PfizerĀ and Moderna, have their vaccines under mass production and administered to the public. This review aims to investigate the most critical vaccines developed for COVID-19 to date

    Dietary Crocin is Protective in Pancreatic Cancer while Reducing Radiation-Induced Hepatic Oxidative Damage

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    Pancreatic cancer is one of the fatal causes of global cancer-related deaths. Although surgery and chemotherapy are standard treatment options, post-treatment outcomes often end in a poor prognosis. In the present study, we investigated anti-pancreatic cancer and amelioration of radiation-induced oxidative damage by crocin. Crocin is a carotenoid isolated from the dietary herb saffron, a prospect for novel leads as an anti-cancer agent. Crocin significantly reduced cell viability of BXPC3 and Capan-2 by triggering caspase signaling via the downregulation of Bcl-2. It modulated the expression of cell cycle signaling proteins P53, P21, P27, CDK2, c-MYC, Cyt-c and P38. Concomitantly, crocin treatment-induced apoptosis by inducing the release of cytochrome c from mitochondria to cytosol. Microarray analysis of the expression signature of genes induced by crocin showed a substantial number of genes involved in cell signaling pathways and checkpoints (723) are significantly affected by crocin. In mice bearing pancreatic tumors, crocin significantly reduced tumor burden without a change in body weight. Additionally, it showed significant protection against radiation-induced hepatic oxidative damage, reduced the levels of hepatic toxicity and preserved liver morphology. These findings indicate that crocin has a potential role in the treatment, prevention and management of pancreatic cancer

    The viral capsid as novel nanomaterials for drug delivery

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    The purpose of this review is to highlight recent scientific developments and provide an overview of virus self-assembly and viral particle dynamics. Viruses are organized supramolecular structures with distinct yet related features and functions. Plant viruses are extensively used in biotechnology, and virus-like particulate matter is generated by genetic modification. Both provide a material-based means for selective distribution and delivery of drug molecules. Through surface engineering of their capsids, virus-derived nanomaterials facilitate various potential applications for selective drug delivery. Viruses have significant implications in chemotherapy, gene transfer, vaccine production, immunotherapy and molecular imaging

    Albumin Nano-Encapsulation of Piceatannol Enhances Its Anticancer Potential in Colon Cancer Via Downregulation of Nuclear p65 and HIF-1 alpha

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    Piceatannol (PIC) is known to have anticancer activity, which has been attributed to its ability to block the proliferation of cancer cells via suppression of the NF-kB signaling pathway. However, its effect on hypoxia-inducible factor (HIF) is not well known in cancer. In this study, PIC was loaded into bovine serum albumin (BSA) by desolvation method as PIC-BSA nanoparticles (NPs). These PIC-BSA nanoparticles were assessed for in vitro cytotoxicity, migration, invasion, and colony formation studies and levels of p65 and HIF-1Ī±. Our results indicate that PIC-BSA NPs were more effective in downregulating the expression of nuclear p65 and HIF-1Ī± in colon cancer cells as compared to free PIC. We also observed a significant reduction in inflammation induced by chemical colitis in mice by PIC-BSA NPs. Furthermore, a significant reduction in tumor size and number of colon tumors was also observed in the murine model of colitis-associated colorectal cancer, when treated with PIC-BSA NPs as compared to free PIC. The overall results indicate that PIC, when formulated as PIC-BSA NPs, enhances its therpautice potential. Our work could prompt further research in using natural anticancer agents as nanoparticels with possiable human clinical trails. This could lead to the development of a new line of safe and effective therapeutics for cancer patients
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