Deep crustal structure and estimation of moho in the lhasa terrane of central tibet

Seismic attributes analysis is applied to INDEPTH II seismic profiles to develop a better understanding of the deep crustal structure and geodynamics of the Lhasa Terrane in the central Tibet area. Analyses indicate that the frequency anomalies are obtained over the range in between 0-30 Hz. Some area of the analyzed traces of the seismic profiles have shown dominated frequency anomaly approximately 10 Hz with little amount of other frequencies. The variation of frequency anomaly is shown to be the indication of theMoho depth of the area. EstimatedMoho depths are found very irregular and varying from20 kmto more than 136 km. The crust is thinner in southern, northern and eastern parts of the area while it is thicker in the western part having asymmetric nature in the central part. This variation might be the result of the complicated tectonic process of the Indian and Eurasian plates. Vertically downward pocket like frequency distributions and similar type frequency distributions at near and far depth are also observed in one of the analyzed sections. It might be indication of uprised asthenospheric matter which exchanged with lithosphere in subduction zones related to the multiple crustal uprising

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Causes of Acute Water Scarcity in the Barind Tract, Bangladesh

The Barind tract is an elevated landmass (about 11-48 m amsl) comprised with Pleistocene terraces and is situated in the northwestern part of Bangladesh. At present, this area faces scarcity of water. The present study is an attempt to unveil the causes of water scarcity of the area. Several aspects like change in climatic condition, irrigation practice and drainage characteristics of major rivers are the prime factors for water scarcity. Interpretation of recent satellite imagery and historical records reveal that the major rivers of the area like Ganges (Padma), Tista and Kosi have remarkably migrated from Barind tract during last few hundred years. Shifting of these rivers causes great change in hydrodynamics of the Barind tract. As a result, flow of other related rivers of the area like the Mahananda, Kulic, Tangon, Punarbhaba, Atrai, Little Jamuna, Karatoya and Nagar reduces remarkably in the dry season. As a result aquifers in the area are not recharged sufficiently by river water in the dry season. India constructed Farakka barrage on the Ganges (Padma) river in 1975 to divert the flow of water from Bangladesh to the other parts of India. This diversion of water also leads to the decreasing of water in the area. Climatic data interpretation of the last 50 years also reveals that annual rainfall in the area is decreasing while overall temperature is increasing. To boost up the cropping intensity (117% to 200% compared to national average of 174%) and to meet present demand 74% of cultivable lands are being irrigated with 96% share of groundwater owing to unavailability or scarcity of rainfall and hence surface water. Irrigation by groundwater has dramatically been increased (250 times) in the last 30 years. Due to over exploitation, water table progressively declined (av. rate 0.10 m/year) which ultimately leads the area to water scarcity zone. The aquifers are confined or semi-confined and do not get appreciable vertical recharge through clay beds. Recharge is mainly through the exposures of sandy strata in the river beds which are flooded in Monsoon season. All sorts of parameters for water scarcity indicate that this condition may aggravate further if no rescue measures are taken immediately

DEEP CRUSTAL STRUCTURE AND ESTIMATION OF MOHO IN THE LHASA TERRANE OF CENTRAL TIBET

Seismic attributes analysis is applied to INDEPTH II seismic profiles to develop a better understanding of the deep crustal structure and geodynamics of the Lhasa Terrane in the central Tibet area. Analyses indicate that the frequency anomalies are obtained over the range in between 0-30 Hz. Some area of the analyzed traces of the seismic profiles have shown dominated frequency anomaly approximately 10 Hz with little amount of other frequencies. The variation of frequency anomaly is shown to be the indication of theMoho depth of the area. EstimatedMoho depths are found very irregular and varying from20 kmto more than 136 km. The crust is thinner in southern, northern and eastern parts of the area while it is thicker in the western part having asymmetric nature in the central part. This variation might be the result of the complicated tectonic process of the Indian and Eurasian plates. Vertically downward pocket like frequency distributions and similar type frequency distributions at near and far depth are also observed in one of the analyzed sections. It might be indication of uprised asthenospheric matter which exchanged with lithosphere in subduction zones related to the multiple crustal uprising

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population