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Sensitivity of Vegetation Type to the Simulation of Land Surface Conditions in the Foothills of Himalayas: Evaluation with In-Situ Observations and Reanalyses
No full textThe Uttarakhand state of the Indian Himalayan region is primarily occupied by needle-leaf and broad-leaf forests Understanding the behavior of a land surface model (LSM) to different vegetation types and forcings is crucial to configuring LSM for this particular region, which is the aim of the study. Various reanalysis products (ERA5-Land, IMDAA, GLDAS, MERRA2, and NEP FNL) are validated against in situ observations at three stations (Kosi-Katarmal, Kantli, and Gangolihat stations) to find the best forcing, and ERA5-Land performed the best. Therefore, one-dimensional Noah-multi parameterization (Noah-MP) LSM is forced with ERA5-Land analysis and IMERG rainfall during 2011–2021. Three vegetation types (Deciduous needle-leaf forest, Evergreen broad-leaf forest, and Barren/Sparsely vegetated type) along with no-vegetation type are considered in LSM and referred to as EXP2, EXP3, EXP4, and EXP1, respectively. Note that the vegetation types in EXP2 and EXP3 are closely related to the actual vegetation observed at in- situ stations, while EXP1 and EXP4 provide sensitivity of land surface conditions to the tree density. The diurnal variation of soil temperature (ST) from EXP2 and EXP3 reasonably agrees with in-situ observations and is better than global/regional analyses, unlike EXP1 and EXP4. EXP2 and EXP3 are comparable for surface sensible and latent heat fluxes in pre-monsoon and southwest-monsoon seasons and could be due to matching with vegetation type and density. The Noah-MP soil moisture (SM) is overestimated (~ 0.09 to 0.15 m3 m-3) against observation, comparable with ESACCI and CYGNSS (− 0.065 to 0.03 m3 m-3) on daily and monthly scales. The SM variations are marginal among the seasons, unlike the ST and surface fluxes. The Noah-MP simulated evapotranspiration is comparable to in-situ observation in EXP2 and EXP3. The study demonstrates the value of LSM in simulating land-surface processes when driven by correct vegetation type, density, and best forcing
Regional Land Surface Conditions Developed Using the High‐Resolution Land Data Assimilation System: Challenges Over Complex Orography Himalayan Region
No full textThe Uttarakhand state of India has been witnessing spatiotemporal variations in heavy rainfall, posing landslides, avalanches, and risks to livelihood and infrastructure. The complex terrain (ranging 250–~7500 m) and weather in this part of the Himalayan region pose difficulties in maintaining land surface observations, thus creating uncertainties in surface energy and hydrological processes. The present study demonstrates the value of the high-resolution land data assimilation system (HRLDAS) integrated at 2 km grid spacing from 2011 to 2021 over Uttarakhand and validated against in situ, satellite, and reanalyzes products. Diurnal variation of sensible heat flux (SHF), and latent heat flux (LHF) are closer to the in situ observations (−35 to 64 Wm-2) than the global and regional analysis (−125 to 129 Wm-2 and −40 to 172 Wm-2) during monsoon season. The HRLDAS soil moisture (SM) is overestimated against in situ and exhibited less error against European Space Agency Climate Change Initiative (ESACCI) (0.02 m3 m-3 with 30%) and Cyclone Global Navigation Satellite System (CYGNSS) (−0.02 m3 m-3 error with 21%). The HRLDAS performs better for soil temperature (ST) with high correlation and less bias (0.94°C and −0.34°C) than the GLDAS (0.83°C and −0.61°C) and IMDAA (0.86°C and 2.2°C), when verified against in situ observations. The spatial distribution of HRLDAS shows maximum ST in the southern parts and minimum ST in the northern parts of the Uttarakhand region and is consistent with the GLDAS and IMDAA during monsoon. HRLDAS shows lesser biases in net radiation (12 Wm-2), SHF (−10 Wm-2), and LHF (9.7 Wm-2) compared to GLDAS (25, −17, 10.3 Wm-2), and IMDAA (38, −11, 16 Wm-2), respectively. Besides the performance, the HRLDAS products represent better spatial heterogeneity than the coarser global and regional analysis and are useful to initializ
Effect of shear flow on the electric polarization of a Sm- <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mi>C</mml:mi><mml:mo>*</mml:mo></mml:msup></mml:math> liquid crystal
No full textThe electric polarization of ferroelectric Smectic-C*(SmC*) liquid crystal is always measured on static samples confined between two fixed electrodes. Here, we study the effect of shear flow on the electric polarization of a SmC* liquid crystal. We observe three distinct regimes in the shear rate-dependent polarization curve. At a low shear rate, the polarization increases rapidly. In the intermediate shear rate range, polarization tends to saturate, and at sufficiently high shear rates, the polarization decreases. The results are discussed based on smectic layer orientations under the combined effect of shear flow and probe electric fields
Minimizing radiative and nonradiative energy leakage in red-light-absorbing supramolecular nanoassemblies to boost oxidative photocatalytic activity in water
No full textHarnessing abundant red-light, which constitutes a significant portion of solar radiation, to energize oxidative transformations is an economic and eco-friendly strategy for sustainable chemistry. Given this consideration, red-light-absorbing J-type nanoassemblies based on a donor–acceptor–donor (D–A–D) building block (BrTPA-Py) with 4-bromo-N,N-diphenylaniline as the donor and pyrazino[2,3-b]pyrazine-2,3-dicarbonitrile as the acceptor have been developed in aqueous media. The strategic incorporation of bromine atoms at the periphery enhanced spin–orbit coupling and restricted nonradiative/radiative decay through bromine⋯bromine noncovalent interactions. Due to the synergistic effect of strong charge-transfer characteristics, presence of bromine atoms and restricted inter/intramolecular motion, rapid intersystem crossing (ISC) is facilitated in BrTPA-Py nanoassemblies, enabling the activation of aerial oxygen through type I (electron transfer) and/or type II (energy transfer) pathways upon irradiation by red-light. The remarkable photosensitization potential of BrTPA-Py nanoassemblies has been unveiled to catalyse the oxidation of phosphines and hydroxylation of arylboronic acids under red-light irradiation, which is unprecedented. This investigation presents a simple design strategy to propel advances in sustainable photocatalysis by regulating the dynamics of excited state under low-energy radiation through the incorporation of halogen atoms in the backbone of the building block with strong charge-transfer characteristics
TCL-628: Prevalence of T-cell lymphomas at the All India Institute of Medical Sciences (AIIMS), New Delhi, India
No full textContext:
T-cell lymphomas (TCL) constitute a heterogeneous category of non-Hodgkin lymphomas (NHL) originating from T lymphocytes and natural killer (NK) cells. They constitute roughly 5% to 10% of all lymphomas inWestern regions and 15% to 20% in East Asia.
Objective:
Adequate data concerning the occurrence and distribution of the T-cell non-Hodgkin lymphoma (T-NHL) subtype are insufficient from India, as indicated by the WHO 2016 classification. Setting, Design, and Participants: This is a retrospective analysis of newly diagnosed patients with NHL treated in the Department of Medical Oncology at AIIMS, New Delhi. Over the course of a decade (2014–2023), a total of 1,800 cases of adult lymphoma (defined as those affecting individuals aged ≥18 years) were recorded. Final tally: 250 cases (14%) of NHL were T-cell–related. The most common subtype of peripheral T-cell lymphoma is PTCL-NOS, which accounts for 90 cases (36%) of the total. Anaplastic large cell lymphoma (ALCL) is the second most common subtype at 24%, followed by extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKTL/NKTCL) at 29 cases (12%), T-cell lymphoblastic lymphoma at 20 cases (8%), angioimmunoblastic T-cell lymphoma at 10 cases (4%), enteropathy-associated T-cell lymphoma at 2%, follicular T-cell lymphoma/hepatosplenic T-cell at 2%, T prolymphocytic leukemia at 0.8%, and three cases that were undescribed (1%). Approximately 10% of all T-cell lymphomas are cutaneous T-cell lymphomas, which accounts for 25 cases. Mycosis fungoides (MF) was the most common one, which was present in 17 cases (7%); followed by Sezary syndrome at 3 cases; lymphomatoid papulosis at 2 cases; and primary cutaneous anaplastic large cell lymphoma, subcutaneous panniculitis-like T-cell lymphoma, and cutaneous gamma delta T-cell lymphoma at 1 case each, respectively.
Conclusion:
The most common subtype of PTCL was PTCL-NOS, followed by ALCL and extranodal NK/T-cell. The incidence of T-cell lymphoma in the Indian population is higher than in the Western population and lower than in the East Asian population; potential factors include variations in viral infections (eg, EBV), genetic susceptibility, and environmental impacts
MuSARCyto : Multi‐head self‐attention‐based representation learning for unsupervised clustering of cytometry data
No full textCytometry enables simultaneous assessment of individual cellular characteristics, offering vital insights for diagnosis, prognosis, and monitoring various human diseases. Despite its significance, the process of manual cell clustering, or gating, remains labor-intensive, tedious, and highly subjective, which restricts its broader application in both research and clinical settings. Although automated clustering solutions have been developed, manual gating continues to be the clinical gold standard, possibly due to the suboptimal performance of automated solutions. We hypothesize that their performance can be improved via an appropriate representation of data from the clustering point of view. To this end, this work presents a novel unsupervised deep learning (DL) architecture wherein an efficient cytometry data representation is learned that helps discover cluster assignments. Specifically, we propose MuSARCyto, a multi-head self-attention-based representation learning network (RN) for the unsupervised clustering of cytometry data, utilizing a fully-connected representation network backbone. To benchmark MuSARCyto against the state-of-the-art cytometry clustering methods, we propose a cluster evaluation metric adjudicator score (Adn), which is an ensemble of prevalent cluster evaluation metrics. Extensive experimentation demonstrates the superior performance of MuSARCyto against the existing state-of-the-art cytometry clustering methods across six publicly available mass and flow cytometry datasets. The proposed DL achitectures are small and easily deployable for clinical settings. This work further suggests using DL methods for identifying meaningful clusters, particularly in the context of critical immunology applications
Corrigendum: Strong
No full textThe proof of [2, Lemma 5.1] is incomplete as it relies on some results in [4], the proof of which contains a gap. The goal of this note is to give a complete and self-contained proof of [2, Lemma 5.1]
Reproductive status modulates colour preference and multimodal cue integration in host plant location by butterflies
No full textButterflies utilize visual, odour and tactile cues, individually or in combination, to navigate their surroundings and make decisions. The effectiveness of these cues varies based on distance and context. Colour is a crucial visual cue across multiple behavioural contexts, including when searching for oviposition sites. We investigated the multimodal integration of information and its modulation of colour preference in the common emigrant butterfly, Catopsilia pomona. Specifically, we tested their preference towards green colour in different scenarios including during the phase in which they are expected to prioritize finding host plants for oviposition. We offered virgin and mated females and males a choice of four colours including green. We show that mated females prefer green but only in the presence of the odour of their preferred host plant. Virgin females and males, irrespective of mating status, preferred colours other than green. Our results suggest that host plant odour and colour are both salient cues for butterflies, and butterflies use them synergistically to find leaves to oviposit on. The sex-specific preference towards green, and the finding that green is preferred only under some contexts, highlights the adaptive plasticity of colour preferences in butterflies
Nanosciences meets ecology: Evolution of stealth nanostructures in insects
No full textIt is difficult to imagine a world without vision - eyes are everywhere around us. The evolution of vision has undeniably been one of the most profound events in the history of life on earth. Animals use their visual system to find food, shelter and mates, as well as in myriad other behaviours that enhance their fitness. On the other hand, vision is also an enemy for multitudes of prey animals that are hunted by visually-guided predators. For such prey animals, avoiding being perceived by the visual system of their potential predators is just as vital as is vision for predators. The earth has witnessed billions of prey species through evolutionary time, and today, some of the most striking adaptations are those that prey animals have evolved as a response to selection by predation. 'Camouflage' is an umbrella term that includes strategies to prevent detection or recognition (Ruxton et al. 2018). For instance, many prey match the colours and patterns of the background, i.e., background matching (Endler 1978). Others have colour patterns that break up the appearance of their body, i.e., disruptive colouration (Thayer 1909). Yet others closely resemble objects that are inedible to their predators, i.e., masquerade (Cott 1940). Camouflage can also involve other sensory systems such as olfaction such that chemically camouflaged prey may escape detection (Ruxton 2009)
High-Temperature Synthesis of Colloidal CH<sub>3</sub>NH<sub>3</sub>PbBr<sub>3</sub> Perovskite Nanoplatelets and Nanocubes
No full textColloidal CsPbX3 (X: Cl, Br, I) and FAPbX3 (FA: formamidinium) perovskite nanocrystals (NCs) are well explored for their size-, shape-, and surface-dependent optoelectronic properties. However, colloidal MAPbX3 (MA: CH3NH3+, methylammonium) perovskite NCs are relatively less explored, even though MAPbBr3 nanoplatelets were the first halide perovskite NCs reported in the literature. Often, the synthesis temperatures of MAPbBr3 NCs are restricted to ∼65 °C, keeping in mind the thermal instability of the MA precursor solution. Here, we advance the synthesis of MAPbBr3 NCs in a nonpolar medium by increasing the synthesis temperature in the range of 120–160 °C. Colloidal MAPbBr3 nanoplatelets with thicknesses of 1.9 and 2.3 nm are prepared at 120 and 140 °C. It is to be noted that for the nanoplatelets, the molar ratio of MA:Pb is <1, along with a significant contribution from capping organic ligands. Further increases in the synthesis temperature to 160 °C lead to the formation of MAPbBr3 nanocubes with a photoluminescence quantum yield of 70–80%. The temperature-dependent control of the size and shape of colloidal MAPbBr3 NCs results in tuning the quantum confinement of excitons, yielding wavelength-tunable optical properties. This temperature-driven control of the size and shape of MAPbBr3 NCs expands their potential for optoelectronic applications