<p>Shiv Nadar University is a comprehensive, multidisciplinary, research-focused, and student-centric University offering a full range of academic programs at the undergraduate, postgraduate and doctoral level. With state-of-the-art infrastructure, the University comprises of academic wings, sophisticated labs, international standard sports facilities, amphitheaters, auditorium, conference rooms and smart classrooms. The University&rsquo;s goal is to become internationally recognized for the quality of its research and creative endeavors and their applicability to improving quality of life, generating new insights and expanding the boundaries of human knowledge creativity. Committed to excellence in teaching, research and service, the University aims to serve the higher education needs of India and the world beyond.</p>

Shiv Nadar University

(SoNS) School of Natural Sciences

In this report, the issue related to nanoparticle (NP) agglomeration upon increasing their loading amount into metal-organic frameworks (MOFs) has been addressed by functionalization of MOFs with alkyne groups. The alkynophilicity of the Pd2+ (or other noble metals) ions has been utilized successfully for significant loading of Pd NPs into alkyne functionalized MOFs. It has been shown here that the size and loading amount of Pd NPs are highly dependent on the surface area and pore width of the MOFs. The loading amount of Pd NPs was increased monotonically without altering their size distribution on a particular MOF. Importantly, the distinct role of alkyne groups for Pd2+ stabilization has also been demonstrated by performing a control experiment considering a MOF without an alkyne moiety. The preparation of NPs involved two distinct steps viz. adsorption of metal ions inside MOFs and reduction of metal ions. Both of these steps were monitored by microscopic techniques. This report also demonstrates the applicability of Pd@MOF NPs as extremely efficient heterogeneous catalysts for Heck-coupling and hydrogenation reactions of aryl bromides or iodides and alkenes, respectively.

Chemistry

World University root node

Inorganic Chemistry

High Loading of Pd Nanoparticles by Interior Functionalization of MOFs for Heterogeneous Catalysis

Ga71 NQR, magnetization and specific-heat measurements have been performed on polycrystalline Ge-doped FeGa3 samples. A crossover from an insulator to a correlated local moment metal in the low-doping regime and the evolution of itinerant ferromagnet upon further doping is found. For the nearly critical concentration at the threshold of ferromagnetic order, xC=0.15, (1/T1T)71 exhibits a pronounced T-4/3 power law over two orders of magnitude in temperature, which indicates three-dimensional quantum critical ferromagnetic fluctuations. Furthermore, for the ordered x=0.2 sample (TC≈6 K), (1/T1T)71 could be fitted well in the frame of Moriya's self-consistent renormalization theory for weakly ferromagnetic systems with 1/T1T∼$\chi$. In contrast to this, the low-doping regime nicely displays local moment behavior where 1/T1T∼$\chi$2 is valid. For T→0, the Sommerfeld ratio $\gamma$=(C/T) is enhanced (70mJ/moleK2 for x=0.1), which indicates the formation of heavy 3d electrons.

Physics

Fulltext

Physical Review B

Towards ferromagnetic quantum criticality in FeGa3-xGex: Ga 71 NQR as a zero-field microscopic probe

The microscopic magnetism in the helical, conical and ferromagnetically polarized phases in an itinerant helical magnet, MnSi, has been studied by an extended 29Si NMR at zero field and under external magnetic fields. The temperature dependence of the staggered moment, MQ (T), determined by the 29Si NMR frequency, $\nu$(T) and the nuclear relaxation rate, 1=T1 (T), at zero field is in general accord with the SCR theory for weak itinerant ferromagnetic metals and its extension to helical magnets. The external field dependence of resonance frequency, $\nu$(H), follows a vector sum of the contributions from the atomic hyperfine and macroscopic fields with a field induced moment characteristic to itinerant magnets. A discontinuous jump of the resonance frequency at the critical field, Hc , between the conical and the polarized phases has also been found, which suggests a first order like change of the electronic states at Hc.

Journal of the Physical Society of Japan

Chiral magnetism in an itinerant helical magnet, MnSi - An extended 29Si NMR Study -

The Cu-catalyzed oxidation of ketones with O2 has recently been extensively utilized to cleave the $\alpha$-C-C bond. This report examines the selective aerobic hydroxylation of tertiary $\alpha$-C-H bonds in ketones without C-C cleavage. We set out to understand the underlying mechanisms of these two possible reactivity modes. Using experimental, in situ IR spectroscopic and computational studies, we investigated several mechanisms. Our data suggest that both C-C cleavage and C-H hydroxylation pathways proceed via a common key intermediate, i.e., an $\alpha$-peroxo ketone. The fate of this peroxide dictates the ultimate product selectivity. Specifically, we uncovered the role of hppH [=1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine] to act not only as a base in the transformation but also as a reductant of the peroxide to the corresponding $\alpha$-hydroxy ketone. This reduction may also be accomplished through exogenous phosphine additives, therefore allowing the tuning of reduction efficiency toward higher driving forces, if required (e.g., for more-activated substrates). The likely competitive pathway is the cleavage of peroxide to the $\alpha$-oxy radical (likely catalyzed by Cu), which is computationally predicted to spontaneously trigger C-C bond cleavage. Increasing the susceptibility of this deperoxidation step via (i) the removal of reductant (use of different base, e.g., DBU) or the modulation of (ii) the substitution pattern toward greater activation (substrate control) and (iii) the nature of Cu catalyst (counterion and solvent dependence) will favor the C-C cleavage product.

Journal of the American Chemical Society

Factors That Control C-C Cleavage versus C-H Bond Hydroxylation in Copper-Catalyzed Oxidations of Ketones with O2

Cancer of large intestine is commonly referred as colorectal cancer, which is also the third most frequently prevailing neoplasm across the globe. Though, much of work is being carried out to understand the mechanism of carcinogenesis and advancement of this disease but, fewer studies has been performed to collate the scattered information of alterations in tumorigenic cells like genes, mutations, expression changes, epigenetic alteration or post translation modification, genetic heterogeneity. Earlier findings were mostly focused on understanding etiology of colorectal carcinogenesis but less emphasis were given for the comprehensive review of the existing findings of individual studies which can provide better diagnostics based on the suggested markers in discrete studies. Colon Rectal Cancer Gene Database (CoReCG), contains 2056 colon-rectal cancer genes information involved in distinct colorectal cancer stages sourced from published literature with an effective knowledge based information retrieval system. Additionally, interactive web interface enriched with various browsing sections, augmented with advance search facility for querying the database is provided for user friendly browsing, online tools for sequence similarity searches and knowledge based schema ensures a researcher friendly information retrieval mechanism. Colorectal cancer gene database (CoReCG) is expected to be a single point source for identification of colorectal cancer-related genes, thereby helping with the improvement of classification, diagnosis and treatment of human cancers. © The Author(s) 2016.

Life Sciences

Database

CoReCG: A comprehensive Database of genes associated with colon-rectal cancer

Rice hybrids are known to withstand moisture deficit stress better than their parental purelines. To study the effect of water deficit stress in rice hybrids, in terms of productivity related traits and physiological parameters pertaining to drought stress, 22 rice hybrids and their parental lines were evaluated under well irrigated and water deficit conditions. Sixteen F1 hybrids showed positive heterosis over their respective mid-parental means for yield and spikelet fertility. Pusa 6A and Vandana was the best cross combination for developing high yielding hybrid rice varieties under drought since they had the highest positive standard heterosis and heterobeltiosis for grain yield, spikelet fertility and membrane stability index (MSI). Among the physiological parameters, MSI was found to reflect the drought tolerance ability of a genotype (pureline/hybrid) better. A set of 60 genome-wide SSR markers were used for prediction of heterotic potential of genotypes under well irrigated and water deficit conditions which revealed that genetic distances and spikelet fertility had a positive and significant correlation. © 2016, Indian Society of Genetics and Plant Breeding. All rights reserved.

Indian Journal of Genetics and Plant Breeding

Physiological and molecular basis of water-deficit stress tolerance in F1 hybrids and their parental lines in rice

Multifunctional reduced graphene oxide (RGO) coated cloths were prepared through the thermal treatment of GO coated cloths without using any harmful reducing agent. The effect of heating temperature on the wetting properties of the cloths was also monitored through contact angle measurement. The highest contact angle 141° was observed for the RGO coated dense cloth while the highest contact angle exhibited by the RGO coated sparse cloth was 130°. The as prepared RGO coated cloths were utilized as a filter and an absorbent for oil/water separation. The RGO coated sparse cloth was utilized as a filter for the separation of an oil/water mixture while the dense cloth was utilized as an absorbent for the selective absorption of oil from water. RGO coated cloths were also explored as an antibacterial agent and the effect of the microstructure of coated cloths on their antibacterial properties was also investigated. The cloth with the dense structure exhibited higher antibacterial activity compared to the sparse cloth. A significant loss of percentage viability up to 98\% was achieved using the RGO coated cloth, proving it highly efficient as an antibacterial agent, which makes it a suitable bandage material for the dressing of open wounds. Apart from being antibacterial, the RGO coated cloths are also hydrophobic in nature so they can protect wound from water and atmospheric moisture which is not possible with ordinary bandages. © 2016 The Royal Society of Chemistry.

RSC Advances

Multifunctional reduced graphene oxide coated cloths for oil/water separation and antibacterial application

Microsomal prostaglandin E synthase-1 (mPGES-1) is a membrane protein which plays crucial role in arachidonic acid metabolism, in the catalysis of PGH2 to PGE2. It is a potential drug target involved in variety of human cancers and inflammatory disorders. In the present study we made an attempt to identify crucial amino acid residues involved in the effective binding of its inhibitors at the active site. Molecular docking and Structure Activity Relationship (SAR) studies were performed. In the present study 127 inhibitors having significant variability in parent scaffold were considered. The results clearly indicated that in the GSH and PGH2 binding site Arg70, Arg73, Asn74, Glu77, His113, Tyr117, Arg126, Ser127, Tyr130, Thr131 and Ala138 consistently form crucial interactions with inhibitors of different classes/scaffolds. These findings are consistent with that of existing reports on the active site residues pivotal at mPGES-1 active site. Further analysis suggested that out of all important amino acid residues identified; Arg73, Asn74, His113, Tyr117, Arg126, Ser127, Tyr130, Thr131 and Ala138 play a crucial role in hydrogen and π-π interactions. The identified amino acid residues can act as target sites for the design and development of drug candidates against mPGES-1. © 2016 Elsevier B.V.

International Journal of Biological Macromolecules

Insights into the structure activity relationship of mPGES-1 inhibitors: Hints for better inhibitor design

Drought and salinity are the major factors that limit chickpea production worldwide. We performed whole transcriptome analyses of chickpea genotypes to investigate the molecular basis of drought and salinity stress response/adaptation. Phenotypic analyses confirmed the contrasting responses of the chickpea genotypes to drought or salinity stress. RNA-seq of the roots of drought and salinity related genotypes was carried out under control and stress conditions at vegetative and/or reproductive stages. Comparative analysis of the transcriptomes revealed divergent gene expression in the chickpea genotypes at different developmental stages. We identified a total of 4954 and 5545 genes exclusively regulated in drought-tolerant and salinity-tolerant genotypes, respectively. A significant fraction (∼47%) of the transcription factor encoding genes showed differential expression under stress. The key enzymes involved in metabolic pathways, such as carbohydrate metabolism, photosynthesis, lipid metabolism, generation of precursor metabolites/energy, protein modification, redox homeostasis and cell wall component biogenesis, were affected by drought and/or salinity stresses. Interestingly, transcript isoforms showed expression specificity across the chickpea genotypes and/or developmental stages as illustrated by the AP2-EREBP family members. Our findings provide insights into the transcriptome dynamics and components of regulatory network associated with drought and salinity stress responses in chickpea.

Scientific Reports

Transcriptome analyses reveal genotype- and developmental stage-specific molecular responses to drought and salinity stresses in chickpea

DNA, in addition to the canonical B-form, can acquire a variety of alternate structures, such as G-quadruplexes. These structures have been implicated in several cellular processes in animals. In this study, we identified different types of G-quadruplex forming sequences (GQSes) in 15 sequenced plants and analyzed their distribution in various genomic features, including gene body, coding, intergenic and promoter regions. G2-type GQSes were most abundant in all the plant species analyzed. A strong association of G3-type GQSes with intergenic, promoter and intronic regions was found. However, G2-type GQSes were enriched in genic, CDS, exonic and untranslated regions. Further, we identified GQSes present in the conserved genes among monocots and dicots. The genes involved in development, cell growth and size, transmembrane transporter, and regulation of gene expression were found to be significantly enriched. In the promoter region, we detected strong co-occurrence of Telobox, ERF, MYB, RAV1B and E2F motifs with GQSes. Further, we validated the structure formation of several plant GQSes, demonstrated their effect on stalling in-vitro replication and revealed their interaction with plant nuclear proteins. Our data provide insights into the prevalence of GQSes in plants, establish their association with different genomic features and functional relevance.