22 research outputs found
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Putting the Boot on the Other Foot: When Local Knowledge is Owned by Local People
There has been a long-standing interest in local knowledge in fisheries research and management. Much of this interest has been in terms of how local knowledge can be interpreted scientifically and used by fisheries experts and managers. Local knowledge becomes the property of scientists, wrapped up in a format and language that is inaccessible to local people. There has been less interest in how local people can use and develop their own knowledge as part of their fisheries management practice, or of the implications of such a degree of ownership for the role of fisheries experts and managers. This paper draws on the experience of local people conducting their own fisheries research according to their own agenda in Northeast Cambodia. The paper begins by describing the process and motivations of this villager-led research and how this was perceived by fisheries experts and managers. The discussion then moves to an analysis of how this research process has generated demands on fisheries experts and managers. Rather than experts defining what is learnt and extracting scientifically valid information from local knowledge, this case study illustrates how local people can identify what needs to be learnt and what role science and experts have in answering these questions. The paper concludes with a discussion of the implications of local people taking ownership of their knowledge, its interpretation and application
Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study
Background: Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. // Methods: We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. // Findings: We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middle-income countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in low-income countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. // Interpretation: Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between low-income, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030
Burden of disease scenarios for 204 countries and territories, 2022–2050: a forecasting analysis for the Global Burden of Disease Study 2021
Dimmable integrated CMOS LED driver based on a resonant DC/DC hybrid-switched capacitor converter
\u3cp\u3eThis paper presents a 7.7-mm\u3csup\u3e2\u3c/sup\u3e on-chip LED driver based on a DC/DC resonant hybrid-switched capacitor converter operating in the MHz range with and without output capacitor. The converter operation allows continuously dimming the LED while keeping control on both peak and average current. Also, it features no flickering even in the absence of output capacitor and for light dimmed down to 10% of the nominal value. The capacitors and switches of the LED driver are integrated on a single IC die fabricated in a low-cost 5 V 0.18-μm bulk CMOS technology. This LED driver uses a small (0.7 mm\u3csup\u3e2\u3c/sup\u3e) inductor of 100 nH, which is 10 times smaller value than prior art integrated inductive LED drivers, still showing a competitive peak efficiency of 93% and achieving a power density of 0.26 W/mm\u3csup\u3e2\u3c/sup\u3e (0.34 W/mm\u3csup\u3e3\u3c/sup\u3e).\u3c/p\u3
A 92.2% peak-efficiency self-resonant hybrid switched-capacitor LED driver in 0.18μm CMOS
This paper presents a LED driver IC based on a self-resonant Hybrid-Switched Capacitor Converter (H-SCC) operating in the MHz range. Capacitors and switches of the LED driver are integrated on-chip in a low-cost 5V 0.18μm bulk CMOS technology. The effective chip area is 7.5mm2. A conventional SMD output capacitor and a 6.4 mm2 150nH SMD air-core inductor are enough to operate the driver in a compact PCB area. Integrated zero-current detection (ZCD) circuitry enables self-resonant operation and Zero-Current Switching independently of the output current, inductor tolerances and/or parasitics, improving the converter efficiency at light loads. A ZCD threshold control enables continuous conduction mode too, to improve efficiency at large currents. The experimental results show a peak efficiency of 92.2% and a maximum power density of 373mW/mm2. The LED driver is able to control a 700mA LED down to 10% of its nominal current and can adjust to LED voltage variations, avoiding the need for LED binning
