Pyrophyllite is a 2:1 layered silicate with interest in ceramics, refractories, and several other important applications. In this work, an investigation into the thermal behaviour of several natural and purified pyrophyllite samples, including a pyrophyllite clay, has been conducted. A previous characterization of these samples has been carried out by AA, XRD, thermal analysis by thermo-dilatometry and DTA-TG, surface area, and SEM-EDX. Thus, relevant chemical, mineralogical, thermal, and textural data of these samples have been obtained. As a second step of this investigation, the thermal behaviour of these pyrophyllite samples has been investigated by XRD and SEM after several thermal treatments at 800, 1100 and 1150 °C during 24 h. The formation of dehydroxylated pyrophyllite as a crystalline phase in the samples was established after 1050 °C by XRD, and its permanency above this temperature, with little changes in morphological features, as revealed by SEM. When thermal treatment was progressive at higher temperatures (1300 °C) the following was evidenced by XRD: (a) the formation and crystallization of mullite (3Al2O3·2SiO2), with a progressive destruction of dehydroxylated pyrophyllite, and (b) the formation of cristobalite (SiO2). This later phase was formed by crystallization of the amorphous silica, detected as a hump by XRD, which is segregated in the solid-state reaction of formation of mullite. This treatment produces a new microstructure with elongated and needle-like crystals of mullite according to SEM observations. All these results have been found of interest for the preparation of ceramic materials, mullite-based ceramics, and refractories using these pyrophyllite samples.
This review aimed to synthesize evidence from 2010–2024 on the nutritional status of adult tribal populations in India, with a focus on Chronic Energy Deficiency (CED) as assessed by Body Mass Index (BMI). Given the persistent health disparities among India’s Scheduled Tribes (STs), the study sought to examine geographic patterns, sex differentials, and contextual determinants of undernutrition across major tribal regions of the country. A systematic literature search was conducted using Google Scholar, PubMed, and JSTOR to identify peer-reviewed studies on adult tribal nutrition in India published between 2010 and 2024. National datasets—including the Census of India (2011) and the National Family Health Survey (NFHS-5, 2019–2021)—were used to provide demographic and health context. Eligible studies reported BMI-based nutritional assessments using the WHO (1995) BMI classification (CED defined as BMI < 18.5 kg/m2). Forty-four studies met the inclusion criteria. Extracted data were summarized by region, tribe, sex, and CED prevalence. The review reveals pronounced regional and sex-based disparities in CED among tribal adults. Northern and Northeastern tribal groups exhibited highly variable CED levels, ranging from very low in the Apatani (≤2%) to extremely high among Gujjar and Bakerwal women (90.7%). Eastern India showed consistently elevated CED, particularly among the Bhumij, Lodha, Kheria, and Santal tribes, with female CED often exceeding 50%. Central and Western tribes—including the Gonds, Kharwar, Mawasi, and Tadvi—displayed widespread undernutrition driven by food insecurity, poverty, and limited healthcare access. Southern India showed critical CED prevalence among Jenu Kuruba and Koraga adults (>90%), while island populations such as the Shompens exhibited low CED but high anaemia burdens. NFHS-5 corroborated these findings, indicating serious national-level CED prevalence among ST adults (18.4% in men, 25.5% in women). Across regions, coexisting burdens of anaemia, tuberculosis, hemoglobinopathies (e.g., sickle cell disease), leprosy, and vector-borne diseases further compounded poor nutritional status. Adult tribal populations in India experience disproportionately high levels of CED, shaped by intersecting structural and cultural determinants including poverty, geographic isolation, gender inequality, food insecurity, and limited access to health services. The wide regional variability underscores the need for targeted, culturally informed, region-specific nutritional interventions. Strengthening surveillance, improving healthcare accessibility, and promoting community-engaged, bottom-up health strategies are essential for reducing disparities and achieving national commitments to the Sustainable Development Goals, particularly the mandate to “Leave no one behind”.
Climate change is exacerbating extreme weather events in West Africa, threatening water resources and livelihoods. The Koliba-Corubal transboundary basin (Guinea-Guinea-Bissau), located primarily outside the Sahel region, constitutes a major freshwater resource for the area. This study analyzes the future daily variability of extreme rainfall and temperatures in this basin using CMIP6 projections. Four climate models (GFDL-ESM4, MPI-ESM1-2-HR, UKESM1-0-LL, IPSL-CM6A-LR) under the SSP1-2.6 and SSP5-8.5 scenarios were used. Six extreme precipitation indices (R99p, Rx3day, Rx5day, SDII, CWD, R20mm) and four extreme temperature indices (TN90p, TNx, TX90p, TXx) were calculated for three time horizons (2021–2050, 2051–2080, 2071–2100) and compared to the reference period 1985–2014. Extreme precipitation decreases considerably in both scenarios (under SSP1-2.6, −45.4% for R99p and −42.0% for Rx3day compared to the reference period 1985–2014), with a marked downward trend at the beginning of the period followed by an increase around 2100 under SSP5-8.5 (R99p: −37.4%; Rx3day: −20.2%). Concurrently, extreme temperatures are increasing significantly, particularly under SSP5-8.5, where TN90p is projected to increase by 169.7% by 2071–2100. Mann-Kendall tests confirm significant trends for most indices under the highest emissions scenario. The spatial distribution shows marked heterogeneity, with higher values in the central mountain areas. These results underscore the urgent need to adapt water resource management strategies and agricultural policies in this transboundary basin in the face of the projected intensification of climate extremes by the end of the century.
We aimed to quantify contemporary changes in physician Medicare reimbursement for surgical and transcatheter valvular procedures. Publicly available 2015–2023 data from the Centers for Medicare & Medicaid Services were used to identify annual physician reimbursement fees for four procedures: surgical aortic valve replacement (SAVR), transcatheter aortic valve replacement (TAVR), mitral valve repair (MVr), and MitraClip. Physician reimbursement fees were adjusted for inflation into 2023 U.S. dollars. Changes over time were analyzed using linear regression to account for differences in average annual U.S. dollar decline, average annual percent change, and total percent change over the study period. Reimbursement for surgical and transcatheter valve procedures declined by a combined total of 28.5%: 25.8% SAVR, 34.2% TAVR, 25.8% MVr, and 28.3% MitraClip. They corresponded to average annual percent changes of −3.7% (SAVR), −5.1% (TAVR), −3.7% (MVr), and −4.1% (MitraClip)—representing a collective decline in reimbursement fee per patient of $784.96 (SAVR), $624.73 (TAVR), $823.54 (MVr), and $706.12 (MitraClip) over the nine-year study span. Over the last decade, physician reimbursement for surgical and transcatheter valve procedures has significantly decreased, potentially threatening access to quality cardiac care within the heart team approach.
Thrust-vectoring UAVs can realize decoupling of position and attitude compared with conventional quadrotors due to the ability to change thrust direction, and are used to perform various complex indoor and outdoor missions. However, existing trajectory generation frameworks are mostly for quadrotors with fixed thrust direction and a coplanar surface, and do not consider the dynamics of thrust-vectoring UAVs. To address this, this paper proposes a multi-objective trajectory generation method for thrust-vectoring UAVs in constraint space. By parametrically modeling the constraint space, the method considers the effects of environmental boundary constraints and platform dynamics characteristics on the collision constraints and motion decoupling of the trajectory, and comprehensively optimizes the trajectory’s indicators of stability, speed, and safety to plan the states and input actions of the flight trajectory. Meanwhile, a trajectory generation evaluation system is proposed, given that compared with the conventional quadratic objective function, the proposed method is effective in reducing the attitude change of the trajectory, improving the rapidity and safety, in which $$L_{\theta}$$ and $$L_{r i s k}$$ are reduced by 70.4% and 19.1%, respectively. Meanwhile, by comparing with the conventional quadrotor, the advantages of the thrust-vectoring in decoupling motion are quantified, especially in reducing the attitude change during flight, the pitch angle of the generated trajectory is reduced from ±30° to within ±20° degrees, which exerts the motion decoupling advantages of the thrust-vectoring.
