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Surface energy balance changes impact on hydrometeorological variables over Indus-Ganga-Brahmaputra
No full textOver the past decades, the estimation of changes in climate and energy mass balance of Earth’s surface has become crucial. The Himalayas, in the South Asian region, are highly vulnerable to precipitation and hydrological/hydrometeorological balance/change. It will significantly affect freshwater availability and the associated sectors of these habitats. The understanding of these changes in hydrological balance for water resource management; identifying the water-sensitive areas; etc. over three major Himalayan river basins, Indus-Ganga-Brahmaputra (IGB), are considered. The geomorphological features, seasonal variability, topographic and geographical differences, landuse/landcover heterogeneity, etc. are distinctly different among them. These in conjugate interaction with above atmosphere induce different feedback mechanisms and processes. Precipitation, turbulent fluxes, evaporation, potential evaporation etc., are considered to assess surface energy balance and different thermodynamical processes. Nonparametric Mann-Kendall method for trend analysis, while the Pettit test for change point detection is employed over data period of 1950–2020. Based on the change point year 1981, the difference in mean precipitation between the periods 1982–2020 and 1950–1981 shows a decreased during monsoon and post-monsoon over GRB and BRB. Interestingly, the change years of potential evaporation and evaporation are highly correlated with monsoon in BRB while the same is weak for GRB. It shows the impact of land use type of the two basins where BRB has more forest cover than of GRB. A lead-lag relationship between the Bowen ratio and different hydrometeorology variables is seen. Present results on changes are important and will be useful for planning and policy for societal benefit viz., better water resource management, potential impacts due to climate change, etc. This study helps policymakers in better understanding of the changing precipitation pattern which will help in formulation of new policies for agriculture and sustainable use of water resources
Two-Way Tuning of Whispering Gallery Mode Resonance of Dual-Frequency Nematic Liquid Crystal Microdroplets
No full textNematic liquid crystals whose dielectric anisotropy changes sign above the crossover frequency are known as dual-frequency nematic liquid crystals (DFNLCs). Here, we report experimental studies on the whispering gallery mode (WGM) optical resonance in fluorescent dye-doped DFNLC microdroplets. The microdroplets are dispersed in a phospholipid-doped glycerol, forming a radial director structure. We investigate the effect of the amplitude and frequency of the applied electric field on the morphology and WGM resonance. We show that the WGM resonance can be tuned by changing the amplitude of the applied field at a fixed frequency and by varying the frequency at a fixed amplitude. Our experiments demonstrate that dual-frequency nematic liquid crystals provide new opportunities for tuning WGM resonance with frequency where the ability to tune by the amplitude of the electric field is limited
Targeting sub-cellular organelles for boosting precision photodynamic therapy
No full textAmong various cancer treatment methods, photodynamic therapy has received significant attention due to its non-invasiveness and high efficiency in inhibiting tumour growth. Recently, specific organelle targeting photosensitizers have received increasing interest due to their precise accumulation and ability to trigger organelle-mediated cell death signalling pathways, which greatly reduces the drug dosage, minimizes toxicity, avoids multidrug resistance, and prevents recurrence. In this review, recent advances and representative photosensitizers used in targeted photodynamic therapy on organelles, specifically including the endoplasmic reticulum, Golgi apparatus, mitochondria, nucleus, and lysosomes, have been comprehensively reviewed with a focus on organelle structure and organelle-mediated cell death signalling pathways. Furthermore, a perspective on future research and potential challenges in precision photodynamic therapy has been presented at the end
Investigating the role of palliative care education in improving the life quality of women with breast cancer
No full textConsidering the high prevalence of breast cancer and its effect on the life quality of affected people, the current study was done to investigate the role of palliative care education in improving the life quality of women with breast cancer. In this clinical trial, 46 breast cancer patients were randomly selected and placed in two intervention and control groups. The control group of routine care and the intervention group additionally received 4 weeks of designed training care. The Missoula quality of life questionnaire was completed before, immediately after, and one month after the intervention for both groups. Data analysis was done by independent t-test, paired t-test, and chi-square with SPSS version 23 software. Based on the obtained results, the average quality of life scores of the intervention group patients after and before the intervention had a statistically significant difference (P = 0.003) and this difference was not significant in the control group (P = 0.67). In addition, there was a statistically significant difference in the average quality of life scores of the two control and intervention groups immediately and one month after the intervention (P<0.0001). From the results of this study, it can be stated that palliative care training can improve the life quality of breast cancer patients, so the systematic and comprehensive provision of this care can be improved by training them with an emphasis on the centrality of the patient's role
Synthesis and Optical Properties of Organic‐Inorganic Hybrid [(18‐Crown‐6)K][MoOCl<sub>4</sub>(H<sub>2</sub>O)]
No full textCrown ether anchored organic-inorganic hybrid halides have been recently reported as interesting luminescent materials in the visible region of electromagnetic spectrum. Is it possible to develop such crown ether anchored hybrid materials for near infrared emission? Motivated by this question, we designed a new hybrid material, namely, [(18-Crown-6)K][MoOCl4 (H2O)]. 18-Crown-6 ether bound with K+ form the cationic part [(18-Crown-6)K]+. The K+ of [(18-Crown-6)K]+ electrostatically interacts with Cl- of the anionic part [MoOCl4 (H2O)]-, forming the hybrid crystal [(18-Crown-6)K][MoOCl4 (H2O)]. It crystallizes in orthorhombic crystal system with Pnma space group. The Mo(V) possesses one d-electron (d1) in C4v point group symmetry in the [MoOCl4 (H2O)]- polyhedra. This electronic configuration leads to multiple spin-allowed d – d transitions along with a ligand to metal charge transfer (LMCT) resulting into multiple optical absorption bands in the near UV-visible-near infrared (NIR) region. The lowest energy d – d transition via 2E ( d1xz , dyz )/ 2E ( dxz, d1yz ) → 2B2 ( d1xy ) leads to NIR PL with peak at 952 nm, but with a poor intensity at room temperature
Sub-seasonal to seasonal (S2S) prediction of dry and wet extremes for climate adaptation in India
No full textExtreme climatic events have considerable impacts on society, and their prediction is an essential tool for climate change adaptation. A reliable forecast of dry and wet extremes is crucial for developing an early warning system and decision-making in agriculture and water resources. Sub-seasonal to seasonal (S2S) forecasts can be valuable for climate adaptation in water resource and agriculture sectors due to their extended range forecast ability and accessibility of different hydrometeorological products. However, the utility of these S2S models’ forecasting capabilities is limited to a certain lead time, rendering them unsuitable for decision-making. We comprehensively examined the prediction skill of nine global S2S prediction models for precipitation and dry and wet extremes over India during the summer monsoon season (June to September). We find that ECCC, NCEP, and UKMO perform better than the other S2S models in predicting dry and wet extremes during the summer monsoon (June-September) in India. Our findings show that the better-performing S2S forecast models can be used to predict wet and dry extreme events several weeks ahead during the summer monsoon season. The extended range forecast system (ERFS), which is currently operational in India, provides better forecast skills for dry and wet extremes than most of the S2S models. However, S2S models provide an extended lead time forecast compared to ERFS. Therefore, a combination of ERFS and better-performing S2S models can be utilized in the early warning of dry and wet extremes at longer lead times
Drivers of Widespread Floods in Indian River Basins
No full textWidespread floods affecting multiple subbasins in a river basin have implications for infrastructure, agriculture, environment, and groundwater recharge. However, the crucial linkage between widespread floods and their drivers remains unexplored for Indian subcontinental river basins. Here, we examine the occurrence and drivers of widespread flooding in seven Indian subcontinental river basins during the observed climate (1959–2020). The peninsular river basins have a high probability of widespread flooding, compared to the transboundary basins of the Ganga and Brahmaputra. Favorable antecedent baseflow and soil moisture conditions, uniform precipitation distribution, and precipitation seasonality determine the probability of widespread floods in Indian river basins. The widespread floods are associated with large atmospheric circulations that cause precipitation in a large part of a river basin. Our findings highlight the prominent drivers and mechanisms of widespread floods with implications for flood mitigation in India
A novel demodulation and selection pilot power trade-off for codebook-based irs with imperfect channel estimates
No full textThe codebook-based scheme for intelligent reflecting surfaces (IRSs) provides flexibility in controlling the training overhead. In it, the reflection pattern with the largest received signal strength is selected from a pre-specified codebook and configured at the IRS. We analyze a training scheme that exploits a novel trade-off between the powers allocated for selection pilots, which are used to select the reflection pattern, and the demodulation pilot, which is used to estimate the channel for demodulation. We develop a novel selection-aware estimator of the beamforming gain of the selected reflection pattern. We derive a tight bound for the achievable rate and an elegant closed-form expression for the beamforming gain. These account for the impact of imperfect channel estimates on the selection of the reflection pattern and the coherent demodulation of the data symbols. The proposed scheme achieves a higher rate than conventional schemes by allocating substantially different powers to the selection and demodulation pilots and data symbols
Tuning the electrocatalytic activity of pd nanocatalyst toward hydrogen evolution and carbon dioxide reduction reactions by nickel incorporation
No full textElectrochemical H2generation and CO2reduction address the energy and environmental crisis plaguing the world. An efficient electrocatalyst would require the lowest overpotential for these reactions. Given its position on the volcano plot near platinum, palladium presents itself as a viable alternative for the hydrogen evolution reaction (HER). However, the activity is limited by a high overpotential. It is also a good electrocatalyst for the CO2reduction reaction (CO2RR) due to the favorable position of the d-band center. Nevertheless, the CO poisoning of the active site results in low electrocatalytic stability. Herein, we report a Ni-incorporated palladium catalyst, NiPd, which reduces water to H2at a very low overpotential of 25 mV η10). Furthermore, it reduces CO2to formate with a very high faradaic efficiency of 97% at a potential of -0.25 V (vs RHE). DFT studies show that Ni inclusion leads to the facile activation of CO2due to a bent adsorption configuration at the catalyst surface. The NiPd catalyst exhibits a strong and stable performance for HER (400 h) as well as for CO2RR (9 h) with high structural integrity as proven by postreaction characterization studies
Computational Assessment of Skull Base Osteomyelitis due to Post-Covid Mucormycosis
No full textThe purpose of this study is to explore colored visualization of grey-scale CT data as a viable method for early detection of skull base degeneration caused by the cerebral progression of Mucormycosis. In addition, the work also aims to assess the pattern of such degeneration from the retrospective data of subjects. CT data of five Mucormycosis patients and five subjects with intact skull bases are used, and grey-scale-based 3D modelling and material characterization of the skull base are performed. Colored contours of Young's modulus over the skull base are generated. The visualized results are corroborated with the help of a numerical comparison of material properties in the different sub-regions of all the skull bases. Both deficiency and degeneration of the bone were visualized, which were primarily confined to the median skull base in all five cases. The observations were corroborated by the comparison of the mean modulus of the median sub-regions with their lateral counterparts (Case #1-5: 84.2%, 72.1%, 58%, 34.7%, and 35%). On the contrary, the material properties were largely uniform in the control group data. The study highlights the aspect of significant silent bone degeneration of the skull base and its effective visualization using material property contours. It elucidates that the medial skull base, which is in proximity to paranasal sinuses is the most vulnerable target for Mucormycosis