Publications by authors named "Bisht G"

Infections linked to Acinetobacter baumannii are one of the main risks of modern medicine. Biofilms formed by A. baumannii due to a protective extracellular polysaccharide matrix make them highly tolerant to conventional antibiotics and raise the possibility of antibiotic resistance.

View Article and Find Full Text PDF

Climate change can alter wetland extent and function, but such impacts are perplexing. Here, changes in wetland characteristics over North America from 25° to 53° North are projected under two climate scenarios using a state-of-the-science Earth system model. At the continental scale, annual wetland area decreases by ~10% (6%-14%) under the high emission scenario, but spatiotemporal changes vary, reaching up to ±50%.

View Article and Find Full Text PDF

Fine quaternary single-domain Heusler alloy nanoparticles with a composition of FeCoGaAl have been synthesized using a simple template-less chemical route for the first time. calculations and standard models have been used to analyze and interpret the experimental findings. The synthesized nanoparticles with an average crystallite size of 42 nm exhibited high saturation magnetization (>5 f.

View Article and Find Full Text PDF

There has been a lot of interest in antimicrobial peptides (AMPs) as potential next-generation antibiotics. They are components of the innate immune system. AMPs have broad-spectrum action and are less prone to resistance development.

View Article and Find Full Text PDF

Light-absorbing particles (LAP) deposited on seasonal snowpack can result in snow darkening, earlier snowmelt, and regional climate change. However, their future evolution and contributions to snowpack change relative to global warming remain unclear. Here, using Earth System Model simulations, we project significantly reduced black carbon deposition by 2081-2100, which reduces the December-May average LAP-induced radiative forcing in snow over the Northern Hemisphere from 1.

View Article and Find Full Text PDF

There is a rising tide of concern about the antibiotic resistance issue. To reduce the possibility of antibiotic-resistant infections, a new generation of antimicrobials must be developed. Antimicrobial peptides are potential alternatives to antibiotics that can be used alone or together with conventional antibiotics to combat antimicrobial resistance.

View Article and Find Full Text PDF

We have discovered spin-state transition (= 2 to= 5/2) of Co ions due to Mg substitution in the CaCoOapparent in the magnetic susceptibility, x-ray photoelectron spectroscopy (XPS), and first-principles study. We also examine the effect of Mg substitution on the magnetic and electronic structure of CaCoOby first-principles calculations. It involves generalized gradient approximation with Coulomb interaction () in exchange-correlation energy functional.

View Article and Find Full Text PDF

Herein we describe a new approach for end-to-end cyclization to construct macrocycles through the inter/intramolecular dehydrogenative coupling of alcohols and ketones in the presence of a Ru-MACHO catalyst. This method is highly atom economical and sustainable and can be used for many substrates. Additionally, this method results in the generation of only water as the byproduct.

View Article and Find Full Text PDF

A base-free and acceptorless Ru-catalyzed dehydrogenative approach has been developed for the synthesis of -heterocycles by using 1,3-dicarbonyls and amino alcohols through a domino sequential enamine formation and intramolecular oxidative cyclization strategy. This unified approach is also applicable for the synthesis of O-heterocycles involving 2-hydroxybenzyl alcohol as a coupling reactant via consecutive C-alkylation and intramolecular cyclization steps. The present protocol is general for the synthesis of varieties of biologically important scaffolds, such as tetrahydro-4-indol-4-one, 3,4-dihydroacridin-1(2)-one, and tetrahydro-1-xanthen-1-ones derivatives using a single catalytic system, viz.

View Article and Find Full Text PDF

A molecular-level description of the aqueous nanochannels in lyotropic liquid crystals (LLCs) is crucial for their widespread utilization in diverse fields. Herein, the polarity and hydrogen bonding effects of LLC water molecules have been simultaneously explored using a single probe, 4'-N,N-dimethylamino-3-hydroxyflavone (DMA3HF), by the unique multiparametric sensitivity of the excited state proton-coupled electron transfer (PCET) phenomenon. The decreased ESIPT efficiency and the significantly retarded ESIPT dynamics (>20 times) of DMA3HF in the LLC phases suggests the dominant influence of strong hydrogen-bonded solute-solvent complexes that leads to a high activation barrier for ESIPT in the mesophases.

View Article and Find Full Text PDF

An efficient and new approach for the synthesis of spirooxindole 2H-azirines via intramolecular oxidative cyclization of 3-(amino(phenyl)methylene)-indolin-2-one derivatives in the presence of I and Cs CO under batch/continuous flow is described. This method is mild and facile to synthesize a variety of spirooxindole 2H-azirines derivatives in gram-scale. Furthermore, we have synthesized spiroaziridine derivatives from spirooxindole 2H-azirines derivatives via addition of Grignard reagent.

View Article and Find Full Text PDF

Background: Alcohol abuse is a major problem worldwide and it affects people's health and economy. There is a relapse in alcohol intake due to alcohol withdrawal. Alcohol withdrawal anxiety-like behavior is a symptom that appears 6-24 h after the last alcohol ingestion.

View Article and Find Full Text PDF

Objectives: To determine the prevalence of foot problems and its related associations in different regions across India among people with Intellectual Disabilities (ID) stratified by age and gender.

Method: A survey was done among a randomly chosen sample of 1517 Indian inhabitants (8-50 years of age) residing in different regions of the country under the drive named Healthy Athlete (HA) Fit Feet Screening Program of Special Olympics Bharat. Chi-Square test is used to draw an inference of prevalence of different foot conditions among the population from different age groups and from different genders.

View Article and Find Full Text PDF

Background: Ubiquitous presence of Mycobacterium fortuitum and ability to cause infections in human beings, hints toward its integral resistance against environmental and host stress conditions. With an aim to identify genes responsible for adapting in vitro acidic stress of M. fortuitum, in the previous study, TnphoA random mutagenesis identified acid susceptible mutant MT727, with mutation in ribosomal maturation factor encoding gene rimP, to be mutated.

View Article and Find Full Text PDF

Mycobacterium fortuitum has emerged as a nosocomial infectious agent and biofilm formation attributed for the presence of this bacterium in hospital environment. Transposon random mutagenesis was used to identify membrane-proteins for biofilm formation in M. fortuitum.

View Article and Find Full Text PDF

The current trend of increment in the frequency of antifungal resistance has brought research into an era where new antifungal compounds with novel mechanisms of action are required. Natural antimicrobial peptides, which are ubiquitous components of innate immunity, represent their candidature for novel antifungal peptides. Various antifungal peptides have been isolated from different species ranging from small marine organisms to insects and from various other living species.

View Article and Find Full Text PDF

A novel and efficient transition-metal-free approach for the exclusive synthesis of -3-(aminobenzylidene/aminoalkylidene)indolin-2-ones in high yield from 2-oxindole and aryl/alkyl nitrile in the presence of LiOBu and 2,2'-bipyridine system is described. In addition, we disclosed a new approach towards the metal-free fluorination using selectfluor and the C═C bond cleavage using CuI and environmentally benign O.

View Article and Find Full Text PDF

Silicon germanium (SiGe or SiGe) is an important semiconductor material for the fabrication of nanowire-based gate-all-around transistors in the next-generation logic and memory devices. During the fabrication process, SiGe can be used either as a sacrificial layer to form suspended horizontal Si nanowires or, because of its higher carrier mobility, as a possible channel material that replaces Si in both horizontal and vertical nanowires. In both cases, there is a pressing need to understand and develop nanoscale etching processes that enable controlled and selective removal of SiGe with respect to Si.

View Article and Find Full Text PDF

Acinetobacter baumannii is one of the clinically important nosocomial pathogen that has become resistant to most of the conventional antimicrobials. Biofilms formed by A. baumannii are difficult to eradicate, thereby highlighting the need for new therapeutic options to treat biofilm associated infections.

View Article and Find Full Text PDF

We can learn about the interactions between nanoparticles (NPs) in solution and solid surfaces by tracking how they move. Here, we use liquid cell transmission electron microscopy (TEM) to follow directly the translation and rotation of Au nanobipyramids (NBPs) and nanorods (NRs) adsorbed onto a SiN surface at a rate of 300 frames per second. This study is motivated by the enduring need for a detailed description of NP motion on this common surface in liquid cell TEM.

View Article and Find Full Text PDF

Graphene Oxide (GO) has been extensively studied in the field of biomedical sciences as one of the most promising biomaterials due to its exceptional physiochemical properties. Experts have long favored anticancer drug cocktails over single drugs, given that the former may provide a more balanced molecular basis for novel chemotherapeutic strategies. Here, we investigated a combinatorial anticancer drug treatment involving the well-proven anticancer drugs quercetin and gefitinib and compared it with gefitinib and quercetin loaded separately onto polyvinylpyrrolidone (PVP)-functionalized graphene oxide (GO-PVP).

View Article and Find Full Text PDF

is an important human pathogenic NTM, which resists stress conditions inside macrophages by exploitation of specific genes. TnphoA-based transposon mutagenesis was employed to identify membrane genes responsible for survival of under such stress conditions. A library of about 450 mutants was constructed after electroporation of vector pRT291 into wild-type .

View Article and Find Full Text PDF

We report here 16S rRNA-based bacterial diversity existing during freezing conditions in a high-altitude Himalayan lake through sequencing a 16S rRNA gene amplicon data set. A total of 121,857 high-quality reads were obtained; 40.78% of the bacterial population was classified to the genus level, while 1.

View Article and Find Full Text PDF

Ru(ii)-NHC catalyzes α-olefination of 2-oxindoles using diaryl methanols in the absence of an acceptor. A wide array of symmetrical and unsymmetrical diaryl methanols undergoes dehydrogenative coupling with 2-oxindole selectively to generate various substituted 3-(diphenylmethylene)indolin-2-one derivatives in good yields and produces environmentally benign by-products, H2 and H2O. This methodology was successfully applied for the synthesis of a bioactive drug i.

View Article and Find Full Text PDF

One-pot wet-chemical synthesis is a simple way to obtain nanoparticles (NPs) with a well-defined shape and composition. However, achieving good control over NP synthesis would require a comprehensive understanding of the mechanisms of NP formation, something that is challenging to obtain experimentally. Here, we study the formation of gold (Au) core-palladium (Pd) shell NPs under kinetically and thermodynamically controlled reaction conditions using in situ liquid cell transmission electron microscopy (TEM).

View Article and Find Full Text PDF