ZnCo2O4 has been synthesized by the low‐temperature and cost‐effective urea combustion method. X‐ray diffraction (XRD), HR‐TEM and selected area electron diffraction (SAED) studies confirmed its ...formation in pure and nano‐phase form with particle size ∼ 15–20 nm. Galvanostatic cycling of nano‐ZnCo2O4 in the voltage range 0.005–3.0 V versus Li at 60 mA g–1 gave reversible capacities of 900 and 960 mA h g–1, when cycled at 25 °C and 55 °C, respectively. These values correspond to ∼ 8.3 and ∼ 8.8 mol of recyclable Li per mole of ZnCo2O4. Almost stable cycling performance was exhibited in the range 5–60 cycles at 60 mA g–1 and at 25 °C with ∼ 98 % coulombic efficiency. A similar cycling stability at 55 °C, and good rate‐capability both at 25 and 55 °C were found. The average discharge‐ and charge‐potentials were ∼ 1.2 V and ∼ 1.9 V, respectively. The ex‐situ‐XRD, ‐HRTEM, ‐SAED and galvanostatic cycling data are consistent with a reaction mechanism for Li‐recyclability involving both de‐alloying‐alloying of Zn and displacement reactions, viz., LiZn ↔ Zn ↔ ZnO and Co ↔ CoO ↔ Co3O4. For the first time we have shown that both Zn‐ and Co‐ions act as mutual beneficial matrices and reversible capacity contribution of Zn through both alloy formation and displacement reaction takes place to yield stable and high capacities. Thus, nano‐ZnCo2O4 ranks among the best oxide materials with regard to Li‐recyclability.
Nanophase ZnCo2O4 has been synthesized, characterized and tested for Li‐recyclability. It exhibited reversible capacities of 900 mAh/g (8.3 moles of Li) in the voltage range 0.005–3.0V vs Li at 60 mA/g up to 60 cycles with excellent rate capability.
In India, acute respiratory illnesses, including pneumonia, are the leading cause of early childhood death. Emergency medical services are a critical component of India's public health ...infrastructure; however, literature on the prehospital care of pediatric patients in low- and middle-income countries is minimal. The aim of this study is to describe the demographic and clinical characteristics associated with 30-day mortality among a cohort of pediatric patients transported via ambulance in India with an acute respiratory complaint.
Pediatric patients less than 18 years of age using ambulance services in one of seven states in India, with a chief complaint of "shortness of breath", or a "fever" with associated "difficulty breathing" or "cough", were enrolled prospectively. Patients were excluded if evidence of choking, trauma or fire-related injury, patient was absent on ambulance arrival, or refused transport. Primary exposures included demographic, environmental, and clinical indicators, including hypoxemia and respiratory distress. The primary outcome was 7 and 30-day mortality. Multivariable logistic regression, stratified by transport type, was constructed to estimate associations between demographic and clinical predictors of mortality.
A total of 1443 patients were enrolled during the study period: 981 (68.5%) were transported from the field, and 452 (31.5%) were interfacility transports. Thirty-day response was 83.4% (N = 1222). The median age of all patients was 2 years (IQR: 0.17-10); 93.9% (N = 1347) of patients lived on family incomes below the poverty level; and 54.1% (N = 706) were male. Cumulative mortality at 2, 7, and 30-days was 5.2%, 7.1%, and 7.7%, respectively; with 94 deaths by 30 days. Thirty-day mortality was greatest among those 0-28 days (N = 38,17%); under-5 mortality was 9.8%. In multivariable modeling prehospital oxygen saturation <95% (OR: 3.18 CI: 1.77-5.71) and respiratory distress (OR: 3.72 CI: 2.17-6.36) were the strongest predictors of mortality at 30 days.
This is the first study to detail prehospital predictors of death among pediatric patients with shortness of breath in LMICs. The risk of death is particularly high among neonates and those with documented mild hypoxemia, or respiratory distress. Early recognition of critically ill children, targeted prehospital interventions, and diversion to higher level of care may help to mitigate the mortality burden in this population.
We report the fabrication of vertically aligned NiO nanowalls on nickel foils using a plasma assisted oxidation method. Electrochemical properties of as-synthesized NiO nanowalls were evaluated by ...galvanostatic cycling and cyclic voltammetery. The results show a capacity of ∼638 (mA h)/g (at 1.25C rate), with excellent capacity retention of up to 85 cycles, when cycled in the range, 0.005−3.0 V vs Li. The superior electrochemical performance of NiO nanowalls in comparison to the previously reported results on nanosized NiO particles can be attributed to its large surface area and shorter diffusion length for mass and charge transport. A possible reaction mechanism is discussed. We also report that electron field emission studies show that the verticllay aligned NiO nanowalls are efficient field emitters with a turn-on field of 7.4 V/µm and a maximum current density of ∼160 µA/cm2 can be achieved.
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► TiP2O7 is synthesized by urea assisted combustion method for first time. ► Synthesized material showed phase pure structure and nano-phase in nature. ► Li/TiP2O7 cell showed, ...0.5mole Li can be reversibly inserted and extracted. ► AC/TiP2O7 hybrid super-capacitor exhibited the maximum energy density of 13Whkg−1.
Nano-size (≤100nm) TiP2O7 is prepared by the urea assisted combustion synthesis, at 450 and 900°C. The compound is characterized by powder X-ray diffraction, Rietveld refinement, high resolution transmission electron microscopy and surface area methods. Lithium cycling properties by way of galvanostatic cycling and cyclic voltammetry (CV) showed a reversible and stable capacity of 60 (±3)mAhg−1 (0.5mole of Li) up to 100 cycles, when cycled at 15mAg−1 between 2–3.4V vs. Li. Non-aqueous hybrid supercapacitor, TiP2O7 (as anode) and activated carbon (AC) (as cathode) has been studied by galvanostatic cycling and CV in the range, 0–3 V at 31mAg−1 and exhibited a specific discharge capacitance of 29 (±1)Fg−1stable in the range, 100–500 cycles. The Ragone plot shows a deliverable maximum of 13Whkg−1 and 371Wkg−1 energy and power density, respectively.
The effect of thermo-mechanical processing of 9Cr-1W-TaV reduced activation ferritic martensitic (RAFM) steel on tensile flow and work hardening behavior has been studied and compared with RAFM steel ...in Normalized and Tempered (N + T) condition. Upon thermo-mechanical treatment (TMT) processing, the tempered martensitic structure of the steel underwent refinement in terms of lath size and precipitates with an increase in dislocation density. Considerable improvement in tensile flow properties without appreciable loss of ductility is observed at test temperatures 300–923 K and at a strain rate of 3 × 10−4 s−1. The plots of work hardening rate (θ) vs. stress (σ) revealed transient and stage-III stages of work hardening for both TMT and N + T steels. However, the TMT processing increased the work hardening of the steel, as manifested by the shift in θ vs. σ plots to higher stresses at all the temperatures and an increase in the fraction of transient stage of θ vs. σ plot up to a temperature of 773 K. Further, an increase in stress to onset of stage-III and the decrease in rate of dynamic recovery (Stage-III) have been observed for TMT steel, in comparison to the steel in N + T condition. This is attributed to the decrease in inter-barrier spacing of the obstacles, in TMT steel, measured analytically. The above-mentioned observations substantiated the beneficial effect of TMT processing on tensile flow and work hardening of the RAFM steel.
•TMT induced refinement of M23C6/MX particles & martensite lath width in RAFM steel.•TMT enhanced tensile strength properties without compromising the ductility.•Work hardening rate of TMT RAFM steel is higher than that of N + T RAFM steel.•TMT steel own low inter-barrier spacing & high stress to onset of dynamic recovery.
Professional wellness is critical to developing and maintaining a health care workforce. Previous work has identified burnout as a significant challenge to professional wellness facing emergency ...medical technicians (EMTs) in many countries worldwide. Our study fills a critical gap by assessing the prevalence of burnout among emergency medical technicians (EMTs) in India.
This was a cross-sectional survey of EMTs within the largest prehospital care organization in India. We used the Maslach Burnout Inventory (MBI) to measure wellness. All EMTs presenting for continuing medical education between July-November 2017 from the states of Gujarat, Karnataka, and Telangana were eligible. Trained, independent staff administered anonymous MBI-Medical Personnel Surveys in local languages.
Of the 327 EMTs eligible, 314 (96%) consented to participate, and 296 (94%) surveys were scorable. The prevalence of burnout was 28.7%. Compared to EMTs in other countries, Indian EMTs had higher levels of personal accomplishment but also higher levels of emotional exhaustion and moderate levels of depersonalization. In multivariate regression, determinants of burnout included younger age, perceived lack of respect from colleagues and administrators, and a sense of physical risk. EMTs who experienced burnout were four times as likely to plan to quit their jobs within one year.
This is the first assessment of burnout in EMTs in India and adds to the limited body of literature among low- and middle-income country (LMIC) prehospital providers worldwide. Burnout was strongly associated with an EMT's intention to quit within a year, with potential implications for employee turnover and healthcare workforce shortages. Burnout should be a key focus of further study and possible intervention to achieve internationally recognized targets, including Sustainable Development Goal 3C and WHO's 2030 Milestone for Human Resources.
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► Li(Li0.1Al0.1Mn1.8)O4 synthesized by polymer precursor method using polyvinyl pyrrolidone. ► Li-cycling studies at 24°C, 600°C and 650°C retained 99 (±1)% capacities after 50 ...cycles. ► At 55°C, 650°C retains 92% of it at the end of 50 cycles. ► 650°C showed much higher capacity-retention at reasonable current rates.
(Li, Al)-co-doped manganese oxide spinel compounds, Li(Li0.1Al0.1Mn1.8)O4 are prepared at temperatures (T), 600, 650 and 750°C by polymer precursor method using polyvinyl pyrrolidone (PVP). The structure and morphology of the porous and sub-micron size particles of the compounds are characterized by the Rietveld refined X-ray diffraction (XRD), infrared and Raman spectroscopy, scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM) and Brunauer, Emmett and Teller (BET) surface area techniques. Galvanostatic charge–discharge cycling in the voltage range of 3.5–4.3V vs. Li at various current (C) rates, 0.5–3C at 24°C up to 60 cycles and at 0.5C and at 55°C up to 50 cycles is carried out. The influence of the Li-excess, the type of Al3+ dopant cation and the amount of fuel (polyvinyl pyrrolidone) used in the synthesis on the electrochemical behavior of the spinel in a Li-cell at room (24°C) and at elevated temperature (55°C) has been studied. Results show that at 24°C and at 0.5C, the phases prepared at 600°C (I) and 650°C (II) showed reversible capacities of 79 and 105mAhg−1 and retained 99 (±1)% of the capacity after 50 cycles. At 1C, 2C and 3C rates, II showed stable capacities of 97, 83 and 57mAhg−1, respectively. At 55°C and at 0.5C, II showed a reversible capacity of 114mAhg−1 and retains 92% of it at the end of 50 cycles, signifying the best cathodic performance for a doped-LiMn2O4. Complementary cyclic voltammetry, impedance spectra and ex situ XRD data are described and discussed.
Conventional cancer targeting with nanoparticles has been based on the assumed enhanced permeability and retention (EPR) effect. The data obtained in clinical trials to date, however, have rarely ...supported the presence of such an effect. To address this challenge, we formulated intracellular nitric oxide-generating nanoparticles (NO-NPs) for the tumor site-specific delivery of NO, a well-known vasodilator, with the intention of boosting EPR. These nanoparticles are self-assembled under aqueous conditions from amphiphilic copolymers of poly(ethylene glycol) and nitrated dextran, which possesses inherent NO release properties in the reductive environment of cancer cells. After systemic administration of the NO-NPs, we quantitatively assessed and visualized increased tumor blood flow as well as enhanced vascular permeability than could be achieved without NO. Additionally, we prepared doxorubicin (DOX)-encapsulated NO-NPs and demonstrated consequential improvement in therapeutic efficacy over the control groups with considerably improved DOX intratumoral accumulation. Overall, this proof of concept study implies a high potency of the NO-NPs as an EPR enhancer to achieve better clinical outcomes.
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