Proton Conducting Organic-Inorganic Composite Membranes for All-Vanadium Redox Flow Battery.

The quest for a cost-effective, chemically-inert, robust and proton conducting membrane for flow batteries is at its paramount. Perfluorinated membranes suffer severe electrolyte diffusion, whereas conductivity and dimensional stability in engineered thermoplastics depend on the degree of functionalization. Herein, we report surface-modified thermally crosslinked polyvinyl alcohol-silica (PVA-SiO2) membranes for the vanadium redox flow battery (VRFB). Hygroscopic, proton-storing metal oxides such as SiO2, ZrO2 and SnO2 were coated on the membranes via the acid-catalyzed sol-gel strategy. The membranes of PVA-SiO2-Si, PVA-SiO2-Zr and PVA-SiO2-Sn demonstrated excellent oxidative stability in 2 M H2SO4 containing 1.5 M VO2+ ions. The metal oxide layer had good influence on conductivity and zeta potential values. The observed trend for conductivity and zeta potential values was PVA-SiO2-Sn > PVA-SiO2-Si > PVA-SiO2-Zr. In VRFB, the membranes showcased higher Coulombic efficiency than Nafion-117 and stable energy efficiencies over 200 cycles at the 100 mA cm-2 current density. The order of average capacity decay per cycle was PVA-SiO2-Zr < PVA-SiO2-Sn < PVA-SiO2-Si < Nafion-117. PVA-SiO2-Sn had the highest power density of 260 mW cm-2, while the self-discharge for PVA-SiO2-Zr was ~3 times higher than Nafion-117. VRFB performance reflects the potential of the facile surface modification technique to design advanced membranes for energy device applications.

Low-Voltage Nongassing Electroosmotic Pump and Infusion Device with Polyoxometalate-Encapsulated Carbon Nanotubes.

A low-voltage nongassing electroosmotic pump was assembled by sandwiching a silica frit between two carbon paper electrodes that were dip-coated with a paste consisting of phosphomolybdic acid/phosphotungstic acid (PMA/PTA)-encapsulated multiwalled carbon nanotubes (MWCNTs) and Nafion. The PMA/PTA encapsulation was a combined effect of their thermomigration and nanocapillary action in MWCNTs. The encapsulated MWCNTs retained desirable redox and charge transfer characteristics of PMA/PTA. The stable voltammogram in 1 M H2SO4 solution exhibited 77% charge retention. A total of three different possible pump configurations, namely, PUMP-I = PMA//SiO2//PMA, PUMP-II = PTA//SiO2//PTA, and PUMP-III = PMA//SiO2//PTA were put together. They are in the sequence of the anode, silica frit, and cathode. All pumps showed a linear dependence on the flow rate with a minimum operating voltage of 1 V, which is well below the thermodynamic potential of water splitting. PUMP-I provided an electroosmotic flux of 43.57 µLmin-1 V-1 cm-2 that matched the requirement of an infusion device like an insulin pump. The device was fabricated and its applicability has been demonstrated by delivering ∼1.8 mL of water at a 10 ± 2 µLmin-1 flow rate at 2 V constant applied voltage over a period of 3 h. Such a wearable device can be programed to deliver model insulin or pain medication drugs for chronic diseases.

Comparison of emergency department trauma triage performance of clinicians and clinical prediction models: a cohort study in India.

OBJECTIVE: The aim of this study was to evaluate and compare the abilities of clinicians and clinical prediction models to accurately triage emergency department (ED) trauma patients. We compared the decisions made by clinicians with the Revised Trauma Score (RTS), the Glasgow Coma Scale, Age and Systolic Blood Pressure (GAP) score, the Kampala Trauma Score (KTS) and the Gerdin et al model. DESIGN: Prospective cohort study. SETTING: Three hospitals in urban India. PARTICIPANTS: In total, 7697 adult patients who presented to participating hospitals with a history of trauma were approached for enrolment. The final study sample included 5155 patients. The majority (4023, 78.0%) were male. MAIN OUTCOME MEASURE: The patient outcome was mortality within 30 days of arrival at the participating hospital. A grid search was used to identify model cut-off values. Clinicians and categorised models were evaluated and compared using the area under the receiver operating characteristics curve (AUROCC) and net reclassification improvement in non-survivors (NRI+) and survivors (NRI-) separately. RESULTS: The differences in AUROCC between each categorised model and the clinicians were 0.016 (95% CI -0.014 to 0.045) for RTS, 0.019 (95% CI -0.007 to 0.058) for GAP, 0.054 (95% CI 0.033 to 0.077) for KTS and -0.007 (95% CI -0.035 to 0.03) for Gerdin et al. The NRI+ for each model were -0.235 (-0.37 to -0.116), 0.17 (-0.042 to 0.405), 0.55 (0.47 to 0.65) and 0.22 (0.11 to 0.717), respectively. The NRI- were 0.385 (0.348 to 0.4), -0.059 (-0.476 to -0.005), -0.162 (-0.18 to -0.146) and 0.039 (-0.229 to 0.06), respectively. CONCLUSION: The findings of this study suggest that there are no substantial differences in discrimination and net reclassification improvement between clinicians and all four clinical prediction models when using 30-day mortality as the outcome of ED trauma triage in adult patients. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT02838459).

Study of pre-hospital care, patterns of injury and outcomes of suburban railway accident victims in Mumbai, India.

Background: . India has one of the largest railway networks, with a high incidence of railway-related accidents and fatality rate of 150/million passengers per year. We evaluated the pre-hospitalization period, pattern of injury and outcome of train accident victims in a metropolitan city. Methods: . For this prospective observational study, we included victims of railway accidents presenting to a public hospital of Mumbai (a metropolitan city) from November 2014 to September 2016. We documented a detailed history of the victims and patterns of injury. Injuries were assessed using the revised trauma score, injury severity score (ISS) and trauma score-ISS. The outcome of surviving persons was assessed using the European quality of life questionnaire (EQ-5D-5L) and visual analogue scale (EQ-VAS). Results: . Eighty-one accident victims were admitted during the study period, of which 37 (46%) were seriously injured. The victims were predominantly male (85%), in the age group of 14-45 years (91%), 23 (28%) were in an intoxicated state. Most accidents happened during morning and evening peak hours (60%). The average time for victims to reach hospital was 38.1 minutes and 77 (95%) were transported by an ambulance accompanied by a doctor, while 8 (10%) received first aid at the railway station or in the ambulance. Ten (12%) accident victims died while 71 (88%) were discharged. Conclusions: . We found a high incidence of people in their productive age group losing their lives to railway accidents, which can be prevented with the help of a robust transport system and training the first responder emergency medical care providers.

Retroperitoneal perforation of the appendix presenting as a right thigh abscess.

A rare case of a retroperitoneal rupture of the appendix is being reported here. A 53-year-old male presented to us with a right sided thigh abscess. There were not any abdominal complaints at presentation. There was continuous discharge after incision and drainage from the thigh. Isolation, in culture, of an enteric bacterium from the pus prompted an evaluation of the gastrointestinal tract as a possible source. An MRI scan revealed fluid tracking from the right paracolic gutter over the psoas sheath and paraspinal muscle into the thigh. A CT scan revealed the perforation at the base of the appendix into the retroperitoneum. At laparotomy the above findings were confirmed. A segmental ileocaecal resection was done. The patient made an uneventful recovery. The absence of abdominal symptoms at presentation leads to delay in diagnosis in such cases. Nonresolving thigh and groin abscesses should lead to the evaluation of the gastrointestinal tract as origin. Diagnostic clues may also be provided by culture reports what as happened in this case.