Currently microorganisms are best identified using 16S rRNA and 18S rRNA gene sequencing. However, in recent years matrix assisted laser desorption ionization-time of flight mass spectrometry ...(MALDI-TOF MS) has emerged as a potential tool for microbial identification and diagnosis. During the MALDI-TOF MS process, microbes are identified using either intact cells or cell extracts. The process is rapid, sensitive, and economical in terms of both labor and costs involved. The technology has been readily imbibed by microbiologists who have reported usage of MALDI-TOF MS for a number of purposes like, microbial identification and strain typing, epidemiological studies, detection of biological warfare agents, detection of water- and food-borne pathogens, detection of antibiotic resistance and detection of blood and urinary tract pathogens etc. The limitation of the technology is that identification of new isolates is possible only if the spectral database contains peptide mass fingerprints of the type strains of specific genera/species/subspecies/strains. This review provides an overview of the status and recent applications of mass spectrometry for microbial identification. It also explores the usefulness of this exciting new technology for diagnosis of diseases caused by bacteria, viruses, and fungi.
Nitrate is an important pollutant found in environmental samples. Nitrate and nitrite pose various environmental as well as health hazards. Different methods of determining nitrate in various ...environmental samples developed during previous years include spectrophotometric, chemiluminescence, electrochemical detection, chromatographic, capillary electrophoretic, spectrofluorimetric methods. Out of these, methods based on spectroscopic detection of nitrate have been discussed in this review article due to their easy availability, high sensitivity, low detection limit, economical and facile nature. Methods based on spectrophotometry, Raman Spectroscopy, IR and FTIR Spectroscopy, atomic absorption spectroscopy (AAS), fluorescence spectroscopy, chemiluminescence, mass spectroscopy, molecular emission cavity analysis (MECA), electron paramagnetic resonance spectrometry (EPR) and nuclear magnetic resonance spectroscopy (NMR) have been reviewed. The basic principle, detection limits, detection range, RSD%, sample throughput/h, advantages and disadvantages have been discussed.
Display omitted
•Spectroscopic methods for detection of nitrate and nitrite have been reviewed.•Their basic principle, advantages and disadvantages have been mentioned.•Detection limits, detection range, RSD%, sample throughput/h have been tabulated.•Literature survey of more than 200 research papers has been presented.
Global average temperature increase during the last century has induced species geographic range shifts and extinctions. Montane floras, in particular, are highly sensitive to climate change and ...mountains serve as suitable observation sites for tracing climate-induced biological response. The Himalaya constitute an important global biodiversity hotspot, yet studies on species' response to climate change from this region are lacking. Here we use historical (1849-50) and the recent (2007-2010) data on temperature and endemic species' elevational ranges to perform a correlative study in the two alpine valleys of Sikkim. We show that the ongoing warming in the alpine Sikkim Himalaya has transformed the plant assemblages. This study lends support to the hypothesis that changing climate is causing species distribution changes. We provide first evidence of warmer winters in the region compared to the last two centuries, with mean temperatures of the warmest and the coldest months may have increased by 0.76±0.25°C and 3.65±2°C, respectively. Warming-driven geographical range shifts were recorded in 87% of 124 endemic plant species studied in the region; upper range extensions of species have resulted in increased species richness in the upper alpine zone, compared to the 19(th) century. We recorded a shift of 23-998 m in species' upper elevation limit and a mean upward displacement rate of 27.53±22.04 m/decade in the present study. We infer that the present-day plant assemblages and community structure in the Himalaya is substantially different from the last century and is, therefore, in a state of flux under the impact of warming. The continued trend of warming is likely to result in ongoing elevational range contractions and eventually, species extinctions, particularly at mountaintops.
The reliability of the communication link is quite common and challenging to handle as the topology changes frequently in vehicular ad hoc networks (VANETs). Another problem with VANETs is that the ...vehicles are from different manufacturers. Hence, the heterogeneity of hardware is obvious. These heterogeneity and reliability problems affect the message dissemination in VANETs. This paper aims to address these challenges by proposing a robust routing protocol capable of ensuring reliable, scalable, and heterogeneity-tolerant message dissemination in VANETs. We first introduced a hybrid hierarchical architecture based on software-defined networking (SDN) principles for VANETs, leveraging SDN's inherent scalability and adaptability to heterogeneity. Further, a road-side unit (RSU)-assisted cloud-based location-aware hybrid routing for software-defined VANETs (SD-VANETs) that we call RC-LAHR was proposed. RC-LAHR was rigorously tested and analyzed for its performance in terms of packet delivery ratio (PDR) and end-to-end delay (EED), along with a comprehensive assessment of network traffic and load impacts on cloud infrastructure and RSUs. The routing protocol is compared with state-of-the-art protocols, Greedy Perimeter Stateless Routing (GPSR) and Opportunistic and Position-Based Routing (OPBR). The proposed routing protocol performs well as compared to GPSR and OPBR. The result shows that the EED is reduced to 20% and the PDR is increased to 30%. The network reliability is also increased up to 5% as compared to the OPBR and GPSR.
Digital change detection techniques by using multi-temporal satellite imagery helps in understanding landscape dynamics. The present study illustrates the spatio-temporal dynamics of land use/cover ...of Hawalbagh block of district Almora, Uttarakhand, India. Landsat satellite imageries of two different time periods, i.e., Landsat Thematic Mapper (TM) of 1990 and 2010 were acquired by Global Land Cover Facility Site (GLCF) and earth explorer site and quantify the changes in the Hawalbagh block from 1990 to 2010 over a period of 20years. Supervised classification methodology has been employed using maximum likelihood technique in ERDAS 9.3 Software. The images of the study area were categorized into five different classes namely vegetation, agriculture, barren, built-up and water body. The results indicate that during the last two decades, vegetation and built-up land have been increased by 3.51% (9.39km2) and 3.55% (9.48km2) while agriculture, barren land and water body have decreased by 1.52% (4.06km2), 5.46% (14.59km2) and 0.08% (0.22km2), respectively. The paper highlights the importance of digital change detection techniques for nature and location of change of the Hawalbagh block.
Alzheimer's disease (AD) is a psychological, biological, or developmental disorder that affects basic mental functioning. AD is generally affiliated with marked discomfort and impaired social, ...professional, or other crucial aspects of life. AD is predominant worldwide, but a disparity in prevalence is observed amongst nations. Around 3/4 of people with Alzheimer's disease are from underdeveloped nations, which receive only 1/10th of global mental health resources. Residents of each community and age category share their presence in the overall load of AD. AD is a multifactorial disease impacted by numerous environmental, genetic, and endogenous elements. Heteromorphic interactive downstream cascades, networks, and molecular mechanisms (inflammation and immune network, cholinergic deficit, lipid transit, endocytosis, excitotoxicity, oxidative stress, amyloid and tau pathology, energy metabolism, neuron and synapse loss, and cell death) have been isolated, imparting a non-dissociative contribution in pathogenesis of AD. In the CNS, the structural organization of cholinergic neurons can give a novel insight into the mechanism of new learning. The alleviation of central cholinergic transposal following destruction in the basal forebrain cholinergic neurons precipitates a decline in neurocognitive symptoms visible in AD patients. The brain of patients suffering from AD exhibits plaques of aggregated amyloid-β and neurofibrillary tangles containing hyperphosphorylated tau protein. Amyloid-β triggers cholinergic loss by modulation of calcium and generation of cell-damaging molecules such as nitric oxide and reactive oxygen species intermediates. The present review focuses on the pathogenic mechanisms related to stages, diagnosis, and therapeutic approaches involved in AD.
Two conformational polymorphs of 5-methyl-2-(2-nitrophenyl)amino-3-thiophenecarbonitrile (ROY) exhibited similar morphology but strikingly different mechanical flexibility, where the yellow needle ...(YN) is exceptionally elastic while orange needle (ON) is highly brittle. Similar to color differentiation, the distinct bending behaviors of YN and ON polymorphs are linked to different molecular conformations. Aided by crystal structural analysis, interaction energies, topology, nanoindentation, and elastic constant calculation, this study reveals new structural insights that explain the strikingly different mechanical behaviors of the two polymorphs.
Microplastics (MPs) as emerging persistent pollutants have been a growing global concern. Although MPs are extensively studied in aquatic systems, their presence and fate in agricultural systems are ...not fully understood. In the agricultural soils, major causes of MPs pollution include application of biosolids and compost, wastewater irrigation, mulching film, polymer-based fertilizers and pesticides, and atmospheric deposition. The fate and dispersion of MPs in the soil environment are mainly associated with the soil characteristics, cultivation practices, and diversity of soil biota. Although there is emerging pollution of MPs in the soil environment, no standardized detection and quantification techniques are available. This study comprehensively reviews the sources, fate, and dispersion of MPs in the soil environment, discusses the interactions and effects of MPs on soil biota, and highlights the recent advancements in detection and quantification methods of MPs. The prospects for future research include biomagnification potency, cytotoxic effects on human/animals, nonlinear behavior in the soil environment, standardized analytical methods, best management practices, and global policies in the agricultural industry for the sake of sustainable development.
Display omitted
•Microplastics are considered as emerging persistent pollutants.•Approximately 32% of plastics produced are available in terrestrial environments.•Annually, 4.8–12.7 Mt of terrestrial plastic wastes enter the ocean.•Sources, fate, and ecological risks of microplastics in soils are elaborated.•Extraction and characterization methods of microplastics in soils are emphasized.
Nitric oxide (NO) is a multifunctional signalling molecule and a neurotransmitter that plays an important role in physiological and pathophysiological processes. In physiological conditions, NO ...regulates cell survival, differentiation and proliferation of neurons. It also regulates synaptic activity, plasticity and vesicle trafficking. NO affects cellular signalling through protein S-nitrosylation, the NO-mediated posttranslational modification of cysteine thiols (SNO). SNO can affect protein activity, protein-protein interaction and protein localization. Numerous studies have shown that excessive NO and SNO can lead to nitrosative stress in the nervous system, contributing to neuropathology. In this review, we summarize the role of NO and SNO in the progression of neurodevelopmental, psychiatric and neurodegenerative disorders, with special attention to autism spectrum disorder (ASD). We provide mechanistic insights into the contribution of NO in diverse brain disorders. Finally, we suggest that pharmacological agents that can inhibit or augment the production of NO as well as new approaches to modulate the formation of SNO-proteins can serve as a promising approach for the treatment of diverse brain disorders.
PDF
