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The distribution and hydrological significance of intact rock glaciers in the north-west Himalaya
No full textIntact rock glaciers are common periglacial landforms that occur in cold alpine mountains and are often considered indicators of alpine permafrost. They can be both active and inactive, but both have ice in them and can be hydrologically significant. Little is known about the distribution of the rock glaciers in the Himalaya at basin-scale and content of water that can be hydrologically significant during the water-stressed months. We have found 967 intact rock glaciers covering an area of 306 km2 in the river basins of Beas, Chenab, Ravi, Sutlej, and Yamuna. Out of these, around 77% are moraine derived and the rest are talus derived. Most of them occur in the elevation between 4000 and 4500 m having a slope of 10� to 30� with a westerly and south-westerly aspect. They start occurring from 3220 to 6206 m, in places with ?10�C to 10�C mean monthly temperature and within 50�100 cm of average monthly precipitation. Their alignment suggests that these rock glaciers occur in the area with low to medium incoming solar radiations. These rock glaciers are generally found where the general rock types are low-grade metamorphic rocks and feldspar-rich intrusive granites occurring beyond the Main Central Thrust in the Higher Himalaya. Finally, we calculated about 8.5 billion m3 volume of water (ice water equivalent) stored in them, considering 60% of the volume of rock glaciers is ice. � 2022 Elsevier B.V., All rights reserved
Two-staged multi-effect distillation for energy efficient brine concentration
No full textMulti-effect distillation (with or without a membrane, MEMD/MED) can achieve a high product recovery in a single pass of feed and is therefore the preferred technology for brine concentration towards zero or minimal liquid discharge. The specific thermal energy consumption of MED/MEMD systems decreases with increasing number of effects (N) since condensing steam is used internally to drive further evaporation multiple times. However, increasing N is limited by the boiling point elevation of the saline brine. This study proposes multi-staging of a parallel-feed MEMD system, with initial treatment in a first stage with high N followed by further brine concentration in a second stage with low N, to save approximately 35 % energy and 17 % on the specific product water cost compared to conventional single-stage operation. A flexible design of industrial forward-feed MED is also proposed such that it can be operated in either 4-effect or 8-effect mode by controlling valves. Such a design enables reducing the energy consumption by up to 40 % when the effluent treatment load is low, through temporally multi-staged operation, as opposed to a conventional 4-effect system which operate for fewer hours when the treatment load reduces. Multi-staging of MED offers an additional degree of freedom to improve the energy efficiency of the energy-intensive brine concentration processes
Phase Separation in Biological Systems: Implications for Disease Pathogenesis
No full textPhase separation is the phenomenon where distinct liquid phases, within solution, play a critical role in the organization and function of biomolecular condensates within cells. Dysregulation of phase separation has been implicated, which can be witnessed in various diseases including neurodegenerative disorders, metabolic syndromes, and cancer. This review provides a comprehensive analysis of the role of phase separation in disease pathogenesis, which focuses on single amino acids, carbohydrates, and nucleotides. Molecular mechanisms underlying phase separation are also discussed with specific examples of diseases associated with dysregulated phase separation. Furthermore, consideration of therapeutic strategies targeting phase separation for disease intervention is explored
Investigation of atmospheric clouds and boundary layer dynamics during a dust storm in the Western-Indian region
No full textThis study investigates the dynamics of atmospheric clouds and boundary layer due to a sudden dust storm over Ahmedabad (23.02° N, 72.57° E), a Western-Indian region, during the pre-monsoon season on May 13, 2024. The storm was triggered by the outflow from convective systems originating in southwest Gujarat and southeast Rajasthan, combined with the significant deepening of the thermal low core over Ahmedabad, which generated strong near-surface winds and initiated the dust storm. These systems and the dust storm were captured by the INSAT-3D satellite and MODIS instrument on NASA's Aqua and Terra satellites. The ground-based Ceilometer Lidar backscatter profile showed an abrupt change in the mixed layer height (MLH) from ∼2.5 km to about 250 m during the storm due to attenuation of the signal by heavy dust load. The MLH, ∼2 km on 12 May (previous day), shallowed to ∼800 m on 14 May (post dust storm day), with increased backscatter indicating high dust concentration. Vertical visibility dropped to 340–660 m during the dust storm. During the storm, relative humidity near the surface increased from 29% to 48% due to moisture transport by frontal system along the density current pathway, while near-surface wind speeds peaked at around 6–10 m/s. After the storm, deep convective clouds formed with a vertical extent of ∼11 km, resulting in approximately 19 mm of rainfall with nearly 15 mm falling within just 1 h indicating the dust-cloud interaction. This study highlights the impact of moist convection and subsequent dust storm on clouds and boundary layer dynamics, emphasizing the importance of ground-based instruments, satellites, and reanalysis datasets in atmospheric monitoring. Understanding the causes, mechanisms, and consequences of dust storms is critical for mitigating their effects and adapting to the changing climate patterns that may influence their frequency and intensity
Synthesis of high-performing metal-organic framework derived CuO- Co3O4 nanoparticles as electrode material for hybrid supercapacitor
No full textA series associated to Rankin-Selberg L -function and modified K -Bessel function
No full textZagier, in 1981, conjectured that the constant term of an automorphic function associated to the Ramanujan delta function, i.e. y12Σ ∞ n=1 τ2(n)e-4πny, has a connection with the nontrivial zeros of ζ(s). This conjecture was finally proved by Hafner and Stopple in 2000. Recently, Chakraborty et al. extended this observation for any normalized Hecke eigenform over SL2(Z). In this paper, we study the infinite series Σ ∞ n=1 cℓ f (n)nν/2Kν (y √ n) for ℓ = 1, 2, where cf (n) denotes the nth Fourier coefficient of a normalized Hecke eigenform f(z) and Kν represents the modified Bessel function of the second kind of order ν. We generalize a recent identity of Berndt et al. We also observe that the aforementioned series corresponding to ℓ = 2 has a connection with the nontrivial zeros of ζ(s)
Observations of the Quiet Sun during the Deepest Solar Minimum of the Past Century with Chandrayaan-2 XSM: Elemental Abundances in the Quiescent Corona
No full textElements with low first ionization potential (FIP) are known to be 3-4 times more abundant in active region loops of the solar corona than in the photosphere. There have been observations suggesting that this observed "FIP bias"may be different in other parts of the solar corona and such observations are thus important in understanding the underlying mechanism. The Solar X-ray Monitor (XSM) on board the Chandrayaan-2 mission carried out spectroscopic observations of the Sun in soft X-rays during the 2019-2020 solar minimum, considered to be the quietest solar minimum of the past century. These observations provided a unique opportunity to study soft X-ray spectra of the quiescent solar corona in the absence of any active regions. By modeling high-resolution broadband X-ray spectra from XSM, we estimate the temperature and emission measure during periods of possibly the lowest solar X-ray intensity. We find that the derived parameters remain nearly constant over time with a temperature around 2 MK, suggesting the emission is dominated by X-ray bright points. We also obtain the abundances of Mg, Al, and Si relative to H, and find that the FIP bias is ?2, lower than the values observed in active regions. � 2021 Elsevier B.V., All rights reserved
On Cohen-Macaulay Posets of Dimension Two and Permutation Graphs
No full textWe characterize Cohen-Macaulay posets of dimension two; they are precisely the shellable and strongly connected posets of dimension two. We also give a combinatorial description of these posets. Using the fact that co-comparability graph of a 2-dimensional poset is a permutation graph, we characterize Cohen-Macaulay permutation graphs
Synthesis and characterization of Tinospora Cordifolia (Giloy) loaded biopolymer films for food packaging
No full textPlastic pollution is a concerning issue affecting the environment and human health globally. Food packaging with conventional plastics is one of the major contributors to plastic pollution. To address this issue, polysaccharide films, known for their biodegradable properties, are being explored as an alternative to food packaging materials. In this study, we developed a chitosan-based biopolymer film loaded with purified Tinospora cordifolia powder using the solvent casting method for food packaging applications. The characterization results confirm the successful incorporation of Tinospora cordifolia powder into chitosan film, by showing the intermolecular hydrogen bonding, changing the film’s nature, and altering the film’s morphology. Water absorption results exhibited improved water resistance, while water vapor permeability (WVP) increased with the addition of purified Tinospora cordifolia. A reduction in the UV-vis transmission value is observed with the addition of Tinospora cordifolia, offering enhanced protection against harmful UV light in food products. The film demonstrated thermal stability in temperature sweep and thermogravimetric analysis (TGA) results. The DPPH and H2O2 radical scavenging assays showed an increase in antioxidant activity of the filler and films correspondingly with an increase in the concentration of Tinospora cordifolia powder, confirming the film’s good antioxidant properties, and Tinospora cordifolia also enhanced antibacterial effects against gram-positive bacteria (S. aureus). Food packaging and coating tests with green chillies, bananas, and eggplant demonstrate prolonged shelf life and confirm excellent soil biodegradability of 98%. Therefore, the chitosan film loaded with Tinospora cordifolia exhibits significant potential for the food packaging industry