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Increased anthropogenic-induced aerosol concentrations over the Himalayas and Tibetan Plateau have affected regional climate, accelerated snow/glacier melting, and influenced water supply and quality in Asia. Although sulfate is a predominant chemical component in aerosols and the hydrosphere, the contributions from different sources remain contentious. Here, we report multiple sulfur isotope composition of sedimentary sulfates from a remote freshwater alpine lake near Mount Everest to reconstruct a two-century record of the atmospheric sulfur cycle. The sulfur isotopic anomaly is utilized as a probe for sulfur source apportionment and chemical transformation history. The nineteenth-century record displays a distinct sulfur isotopic signature compared with the twentieth-century record when sulfate concentrations increased. Along with other elemental measurements, the isotopic proxy suggests that the increased trend of sulfate is mainly attributed to enhancements of dust-associated sulfate aerosols and climate-induced weathering/erosion, which overprinted sulfur isotopic anomalies originating from other sources (e.g., sulfates produced in the stratosphere by photolytic oxidation processes and/or emitted from combustion) as observed in most modern tropospheric aerosols. The changes in sulfur cycling reported in this study have implications for better quantification of radiative forcing and snow/glacier melting at this climatically sensitive region and potentially other temperate glacial hydrological systems. Additionally, the unique Δ33S-δ34S pattern in the nineteenth century, a period with extensive global biomass burning, is similar to the Paleoarchean (3.6-3.2 Ga) barite record, potentially providing a deeper insight into sulfur photochemical/thermal reactions and possible volcanic influences on the Earth's earliest sulfur cycle.

The extent to which stratospheric intrusions on synoptic scales influence the tropospheric ozone (O3) levels remains poorly understood, because quantitative detection of stratospheric air has been challenging. Cosmogenic 35S mainly produced in the stratosphere has the potential to identify stratospheric air masses at ground level, but this approach has not yet been unambiguously shown. Here, we report unusually high 35S concentrations (7,390 atoms m-3; ∼16 times greater than annual average) in fine sulfate aerosols (aerodynamic diameter less than 0.95 µm) collected at a coastal site in southern California on May 3, 2014, when ground-level O3 mixing ratios at air quality monitoring stations across southern California (43 of 85) exceeded the recently revised US National Ambient Air Quality Standard (daily maximum 8-h average: 70 parts per billion by volume). The stratospheric origin of the significantly enhanced 35S level is supported by in situ measurements of air pollutants and meteorological variables, satellite observations, meteorological analysis, and box model calculations. The deep stratospheric intrusion event was driven by the coupling between midlatitude cyclones and Santa Ana winds, and it was responsible for the regional O3 pollution episode. These results provide direct field-based evidence that 35S is an additional sensitive and unambiguous tracer in detecting stratospheric air in the boundary layer and offer the potential for resolving the stratospheric influences on the tropospheric O3 level.

This paper starts with a brief background of the link between creativity and education, including the beginning of the most recent interest in the two. There is a short summary of the reasons for this renewed interest. This is followed by a discussion into the dissatisfactions over current education and its changing role in the light of increasing importance being accorded to creativity. Lastly, evidence in educational policy documents from around the world is presented to show the steps being taken for implementation of creativity in education.

Any policy reform in education is highly effective when it is planned and implemented "holistically" and yet, it is the most challenging way forward. Many countries in Asia have reformed their English language policies and syllabi in the last two decades due to the increasing value of the language worldwide. Motivated by a "communicative approach" to English language teaching, Bangladesh was one of the countries that launched such a reform in the 1990s. However, this reform has been criticised for imposing the changes on teachers without preparing them sufficiently. More importantly, there is limited evidence as to how much the secondary English language assessment system is aligned with the changes introduced in the curriculum. In order to explore this gap, a medium-scale study was conducted in 38 secondary schools in Bangladesh, following a mixed methods approach. The findings highlighted a "mismatch" between the intended English language learning outcomes and current assessment practices, including the resulting challenges faced by the teachers. This paper argues that language education reform is likely to fail if the assessment system is not aligned with the curriculum.

In the Least Economically Developed Countries (LEDCs), School Based Teacher Development (SBTD) is sometimes advocated as a potential mechanism for improving the classroom practices experienced by millions of children in a complete school system, as quickly as possible. Robust evidence is required for approaches to be implemented with some confidence by Government development agencies, such as the UK Department for International Development (DFID). SBTD has a long history stemming from ideas of school-based curriculum development, which underlay the ideas on teacher-as-researcher, and is typically advocated in the developed world based on a view of the teacher as a professional. How might such notions play out, and to what effect, in LEDC contexts? This article examines the issues at stake in introducing SBTD in LEDCs, by examining: the nature of the evidence for various forms of teacher development, the nature of SBTD in particular and the evidence for its effectiveness. The latter issues will be illustrated through examination of English in Action (EIA, www.eiabd.com), a large-scale SBTD programme for primary and secondary English language (EL) teachers serving government schools across Bangladesh. (Contains 8 figures and 6 tables.)

Background: Individuals with COVID-19 may experience respiratory collapse due to severe bilateral pneumonia. Because there was a substantial threat of infections during biopsies, histological samples are rare. Objective: The present study aimed to assess the histomorphological alterations in the lungs affected by COVID-19 using a CT scan and lung ultrasonography. Methodology: We conducted a prospective observational study on individuals who had severe COVID-19. Twelve exploration zones were created from the thorax to link lung ultrasonography (LU) and CT-scan findings. Each block was split into 7 cuts of 2.5µm thick sections. Specimens for Histology were stained with Weigert-Van-Giesson (to evaluate elastic fiber architecture) and Masson's trichrome eosine and hematoxylin, (for collagen deposition and fibrosis). SPSS 20 was used for the analysis of the data. Results: The patients' mean age was 61.65 ± 12.57 years, with 96% of them being male. A total of 179 thoracic areas were examined in 25 individuals who underwent evaluation using both thoracic LU and chest CT scans. B2-lines were the most common LU finding (49.7%). Ground-glass opacity (GGO), was the most common CT-scan result (31.3%). Findings from a pathological CT scan were frequently seen when B2-lines or C-lines were found using LU (positive predictive value, PPV, 85.1%). Diffuse alveolar damage (DAD) accounted for 75% of the histological samples, while persistent interstitial inflammation (25%). Conclusion: Lung Ultrasonography (LU) frequently reveals B2-lines and C-profiles in patients experiencing severe COVID-19 and respiratory impairment. These findings often correspond to various CT patterns and histological outcomes such as Diffuse Alveolar Damage (DAD) and lung fibrosis. LU holds potential in predicting prognosis, assessing response to therapy, and optimizing the necessity for CT scans. [ABSTRACT FROM AUTHOR]

Background: Preoperative surgical planning assumes a central role in avoiding catastrophic outcomes of a surgery in the field of renal transplantation, and other urological procedures. This study was aimed to study the different anatomic patterns of human renal venous system. Methods: It is a descriptive cross-sectional study including 50 adult male cadavers with well-preserved kidneys, renal vasculature and the inferior vena cava. Cadavers with deformed or congenitally anomalous kidney, evidence of surgery, solitary kidney, tumours of kidneys or injured renal vessels / inferior vena cava were excluded from the study. The kidneys, renal veins and the inferior vena cava were exposed. After securing inferior vena cava fifty ml mixture of Indian ink and gelatine was injected into renal veins via inferior vena cava and was allowed to solidify. Following this, the renal venous anatomy was studied. Results: Twenty-eight cadavers had their right renal vein formed by 2 tributaries (56%), 13 (26%) had 3 tributaries, 5 (10%) had 4 tributaries, 1 cadaver had a posterior tributary (2%), while 3 cadavers had other numbers of tributaries (6%). Out of total 50 cadavers 40 (80%) had normal distribution of right renal vein. Additional renal veins were found in 14 (7%) cadavers, double renal veins in 1 (2%) and proximally double renal veins in 2 cadavers (4%). Conclusions: There is considerable variation in renal venous anatomy. Knowledge of common venous patterns is necessary for minimizing intraoperative damage to renal anatomy and to prevent intra-and post-operative complications. [ABSTRACT FROM AUTHOR]

Increased anthropogenic-induced aerosol concentrations over the Himalayas and Tibetan Plateau have affected regional climate, accelerated snow/glacier melting, and influenced water supply and quality in Asia. Although sulfate is a predominant chemical component in aerosols and the hydrosphere, the contributions from different sources remain contentious. Here, we report multiple sulfur isotope composition of sedimentary sulfates from a remote freshwater alpine lake near Mount Everest to reconstruct a two-century record of the atmospheric sulfur cycle. The sulfur isotopic anomaly is utilized as a probe for sulfur source apportionment and chemical transformation history. The nineteenth-century record displays a distinct sulfur isotopic signature compared with the twentieth-century record when sulfate concentrations increased. Along with other elemental measurements, the isotopic proxy suggests that the increased trend of sulfate is mainly attributed to enhancements of dust-associated sulfate aerosols and climate-induced weathering/erosion, which overprinted sulfur isotopic anomalies originating from other sources (e.g., sulfates produced in the stratosphere by photolytic oxidation processes and/or emitted from combustion) as observed in most modern tropospheric aerosols. The changes in sulfur cycling reported in this study have implications for better quantification of radiative forcing and snow/glacier melting at this climatically sensitive region and potentially other temperate glacial hydrological systems. Additionally, the unique Δ33S-δ34S pattern in the nineteenth century, a period with extensive global biomass burning, is similar to the Paleoarchean (3.6-3.2 Ga) barite record, potentially providing a deeper insight into sulfur photochemical/thermal reactions and possible volcanic influences on the Earth's earliest sulfur cycle. [ABSTRACT FROM AUTHOR]

The extent to which stratospheric intrusions on synoptic scales influence the tropospheric ozone (O3) levels remains poorly understood, because quantitative detection of stratospheric air has been challenging. Cosmogenic 35S mainly produced in the stratosphere has the potential to identify stratospheric air masses at ground level, but this approach has not yet been unambiguously shown. Here, we report unusually high 35S concentrations (7,390 atoms m-3; ~16 times greater than annual average) in fine sulfate aerosols (aerodynamic diameter less than 0.95 µm) collected at a coastal site in southern California on May 3, 2014, when groundlevel O3 mixing ratios at air quality monitoring stations across southern California (43 of 85) exceeded the recently revised US National Ambient Air Quality Standard (daily maximum 8-h average: 70 parts per billion by volume). The stratospheric origin of the significantly enhanced 35S level is supported by in situ measurements of air pollutants and meteorological variables, satellite observations, meteorological analysis, and box model calculations. The deep stratospheric intrusion event was driven by the coupling between midlatitude cyclones and Santa Ana winds, and it was responsible for the regional O3 pollution episode. These results provide direct field-based evidence that 35S is an additional sensitive and unambiguous tracer in detecting stratospheric air in the boundary layer and offer the potential for resolving the stratospheric influences on the tropospheric O3 level. [ABSTRACT FROM AUTHOR]