Explaining the natural and anthropogenic factors driving glacier recession in Kashmir Himalaya, India.

Glaciers across the Kashmir Himalayan region are melting at an accelerated pace compared to other regions across the Himalayan arc. This study analyzed the recession patterns of nine glaciers in the Kashmir Himalaya region over 28 years between 1992 and 2020 using satellite images and field measurements. The recession patterns were correlated with debris cover, topographic factors, and ambient black carbon (BC) concentration at glacier sites. HYSPLIT model was used to track the air mass sources at a 7-day time-step from September 1, 2014, to September 28, 2014, over the selected region. All nine glaciers revealed high recession as indicated by changes in the area (average recession: 20.8%) and snout position (~ 14 m a-1). The relative percentage of debris on each glacier varied between ~ 0% (clean glacier) and 43%. Although the investigated glaciers lie in the same climatological regime, their topographical behavior is dissimilar with mean altitude ranging between 4000 and ~ 4700 m asl and the average slope varying from 17 to 24°. All the investigated glaciers are north-facing except G3 (southerly aspect). Our results indicate anomalously high ambient BC concentrations, ranging from 500 to 1364 ng m-3, at the glacier sites, higher than previously studied for glaciers in the Himalayas and neighboring Tibetan Plateau. The backward air-mass trajectory modeling indicated both local and global sources of particulate matter in the study area. A comparative analysis of BC measurements and glacier recession with the studies conducted across high Asia indicated the influence of BC in accelerating the melting of glaciers in the Kashmir region.

Towards understanding various influences on mass balance of the Hoksar Glacier in the Upper Indus Basin using observations.

Mass balance is a good indicator of glacier health and sensitivity to climate change. The debris-covered Hoksar Glacier (HG) in the Upper Indus Basin (UIB) was studied using direct and geodetic mass balances. During the 5-year period from 2013 to 2018, the glacier's mean in situ mass balance (MB) was - 0.95 ± 0.39 m w.e. a-1. Similarly, the glacier's mean geodetic MB from 2000 to 2012 was - 1.20 ± 0.35 m w.e. a-1. The continuously negative MB observations indicated that the HG is losing mass at a higher rate than several other Himalayan glaciers. The glacier showed increased mass loss with increasing altitude, in contrast to the typical decreasing MB with increasing elevation, due to the existence of thick debris cover in the ablation zone, which thins out regularly towards the accumulation zone. Rising temperatures, depleting snowfall and increasing black carbon concentration in the region, indicators of climatic change, have all contributed to the increased mass loss of the HG. During the lean period, when glacier melt contributes significantly to streamflow, the mass loss of glaciers has had a considerable impact on streamflow. Water availability for food, energy, and other essential economic sectors would be adversely affected, if, glaciers in the region continued to lose mass due to climatic change. However, long-term MB and hydro-meteorological observations are required to gain a better understanding of glacier recession in the region as climate changes in the UIB.

The satellite observed glacier mass changes over the Upper Indus Basin during 2000-2012.

Decadal glacier thickness changes over the Upper Indus Basin in the Jammu and Kashmir Himalaya were estimated using the TanDEM-X and SRTM-C Digital Elevation Models (DEMs) from 2000 to 2012. In the study area 12,243 glaciers having 19,727 ± 1,054 km2 area have thinned on an average of - 0.35 ± 0.33 m a-1 during the observation period. The highest thinning of - 1.69 ± 0.60 m a-1 was observed in the Pir Panjal while as the marginal thinning of - 0.11 ± 0.32 m a-1 was observed for the glaciers in the Karakoram. The observed glacier thickness changes indicated a strong influence of the topographic parameters. Higher thickness reduction was observed on the glaciers situated at lower altitudes (- 1.40 ± 0.53 m a-1) and with shallower slopes (- 1.52 ± 0.40 m a-1). Significantly higher negative thickness changes were observed from the glaciers situated on the southern slopes (- 0.55 ± 0.37 m a-1). The thickness loss was higher on the debris-covered glaciers (- 0.50 ± 0.38 m a-1) than on the clean glaciers (- 0.32 ± 0.33 m a-1). The cumulative glacier mass loss of - 70.32 ± 66.69 Gt was observed during the observation period, which, if continued, would significantly affect the sustainability of water resources in the basin.

Analytical Expressions for the Mixed-Order Kinetics Parameters of TL Glow Peaks Based on the two Heating Rates Method.

The two heating rates method (originally developed for first-order glow peaks) was used for the first time to evaluate the activation energy (E) from glow peaks obeying mixed-order (MO) kinetics. The derived expression for E has an insignificant additional term (on the scale of a few meV) when compared with the first-order case. Hence, the original expression for E using the two heating rates method can be used with excellent accuracy in the case of MO glow peaks. In addition, we derived a simple analytical expression for the MO parameter. The present procedure has the advantage that the MO parameter can now be evaluated using analytical expression instead of using the graphical representation between the geometrical factor and the MO parameter as given by the existing peak shape methods. The applicability of the derived expressions for real samples was demonstrated for the glow curve of Li2B4O7:Mn single crystal. The obtained parameters compare very well with those obtained by glow curve fitting and with the available published data.

An Analysis of Single Nucleotide Substitution in Genetic Codons - Probabilities and Outcomes.

BACKGROUND: Single nucleotide substitutions (SNS) in genetic codon are of prime importance due to their ability to alter an amino acid sequence as a result. Given the nature of genetic code, any SNS is expected to change the protein sequence randomly into any of the 64 possible codons. In this paper, we present a theoretical analysis of how single nucleotide substitutions in genetic codon may affect resulting amino acid residue and what is the most likely amino acid that will get selected as a result. METHODS: A probability matrix was developed showing possible changes and routes likely being followed as a result of base substitution mutation causing changes at the translational level for the amino acid being encoded. RESULTS: We observe that in event of single base pair substitution in a given amino acid; a chosen set of amino acids is theoretically more probable to be resulted suggesting a directional rather than a random change. This study also indicates that for a given amino acid coded by a number of synonymous codons, all synonymous codons will result into same list of amino acids in case of all possible SNS at three positions. CONCLUSION: The present work has resulted into development of a theoretical probability matrix which can be used to predict changes in amino acid residues in a protein sequence caused by single base substitutions.

Prolonged Impacted Denture in the Esophagus: A Case Report and Review of the Literature.

Foreign body ingestion and aspiration is among the most common causes of emergency department visit associated with high morbidity and mortality. Ingested and aspirated denture is rare conditions being scarcely reported in the literature. We herein report a 57-year-old man who presented with 2-day history of liquid and solid dysphagia who was diagnosed to have impacted denture in esophagus since 3 years prior to presentation. He was diagnosed to have esophagus adenocarcinoma and had undergone esophageal radiotherapy. The denture was removed successfully using esophagoscopy and the patient was discharged after 48-hour care with good condition. To prevent accidental ingestion, dentures should be made to fit properly. Damaged or malfitting dentures should be discarded and replaced. Patients should be strongly advised against wearing them during sleep-time.

Investigation of temporal change in glacial extent of Chitral watershed using Landsat data: a critique.

Himalayan glaciers are showing consistent signs of recession similar to glaciers elsewhere in the world with the exception of slight mass gain or stability in Karakoram. Deficient knowledge regarding the processes controlling the glacier dynamics together with remoteness, rugged terrain, insufficient in situ measurements, unsuitable datasets, and scanty network of meteorological stations has always been a big challenge in projecting future glacier dynamics in the region. Here, we present a number of scientific concerns regarding the appropriateness of data sets and methods adopted by a study carried out by Naeem et al. (2016), published in the journal of Environmental Monitoring and Assessment to investigate and project glacier dynamics in Chitral watershed using Landsat data. The use of predominantly snow and cloud covered satellite images especially for 2006 and 2007 strongly questions the glacier fluctuation estimates put forth by the authors. The inferences from existing scientific literature suggesting robustness of semi-automatic methods for glacier mapping challenge the use of unsupervised classification approach for delineating glacier extents as adopted in Naeem et al. (2016). Considering the scientific concerns and loopholes in the study by Naeem et al. (2016), the glacier fluctuations in Chitral watershed need to be reassessed.