Theoretical investigation of quantum capacitance of Co-doped α-MnO2 for supercapacitor applications using density functional theory.

The rapid depletion of fossil fuels and ever-growing energy demand have led to a search for renewable clean energy sources. The storage of renewable energy calls for immediate attention to the fabrication of efficient energy storage devices like supercapacitors (SCs). As an electrode material for SCs, MnO2 has gained wide research interest because of its high theoretical capacitance, variable oxidation state, vast abundance, and low cost. However, the low electric conductivity of MnO2 limits its practical application. The conductivity of MnO2 can be enhanced by tuning the electronic states through substitution doping with cobalt. In the present work, first principles analysis based on density functional theory (DFT) has been used to examine the quantum capacitance (CQC) and surface charge (Q) of Co-doped MnO2. Doping enhanced the structural stability, electrical conductivity, potential window, and quantum capacitance of α-MnO2. The shortened band gap and localized states near the Fermi level improve the CQC of α-MnO2. For the narrow potential range (-0.4 to 0.4 V), the CQC is observed to increase with doping concentration. The highest CQC value at +0.4 V is observed to be 2412.59 µF cm-2 for Mn6Co2O16 (25% doping), five times higher than that of pristine MnO2 (471.18 µF cm-2). Mn6Co2O16 also exhibits better CQC and 'Q' at higher positive bias. Hence, it can be used as an anode material for asymmetric supercapacitors. All these results suggest better capacitive performance of Co-doped α-MnO2 for aqueous SCs and as an anode material for asymmetric supercapacitors.

Understanding of HIV/AIDS in the international border area, Manipur: Northeast India.

Manipur, an international border region has the highest incidence of human immunodeficiency virus (HIV)-1 infection in India. Nevertheless, there have been no analytical reviews of research article published within this region. In this review, the authors aim to draw the attention of policy makers, medical practitioners and researchers in adopting new strategies to limit the expansion of HIV/acquired immunodeficiency syndrome (AIDS) not only in Manipur but also in other international border areas. A systematic search for published literature in last decade was performed based on the keywords 'Manipur' and 'HIV' using the PubMed. Twenty-six articles were selected and reviewed. There were high incidence of drug resistance (53%), emergence of recombinant virus (32%) and increased incidence of co-infection with hepatitis C virus. The prime cause of the HIV is due to the uses of 'heroin' smuggled from the 'South Asia Golden Triangle' and complex patterns of cross-border movement for trade and commerce. The drug abuse, social stigma, geographical location and resource limitation and socio-political problem of the region have contributed strongly on spreading and failure of preventively programme of HIV/AIDS. This review will provide vital knowledge for the policy makers and clinicians for sentinel surveillance of AIDS pandemic in Manipur and other international border regions.

Polypyrrole and activated carbon enriched MnCo2O4 ternary composite as efficient electrode material for hybrid supercapacitors.

The development of proficient electrode materials is one of the major tasks faced by modern techniques for energy storage. Integrating different materials with synergistic effects can be a valuable strategy for designing storage devices with high capacity and energy density. The spinel manganese cobaltite (MnCo2O4) is an outstanding candidate for supercapacitors owing to its remarkable pseudocapacitive behavior. However, it suffers from low electric conductivity and limited cyclic stability. To overcome its limitations, activated carbon with superior cyclic stability and polypyrrole with high electric conductivity can be incorporated in MnCo2O4. The synergistic effect of these components offers high capacitance, better conductivity, and superior cyclic performance to the ternary composite. Herein, the MnCo2O4/AC/PPY ternary composite has been synthesized by a facile approach. The optimized ternary composite (MAP-20) exhibited a wonderful capacitance of 945.77 F g-1 at five mV s-1 compared to pristine MnCo2O4 (254.98 F g-1). The real-time applicability of the optimized composite was tested with asymmetric device configuration. The asymmetric device with MAP-20 and MnO2/AC electrodes exhibited a wonderful Ed of 88.12 W h kg-1 (Pd ∼ 1.6 kW kg-1). The asymmetric device also exhibited excellent cyclic performance of 89.68% for 10 000 cycles. Further, the real-time applicability of the device was tested by illuminating a 39 red LED panel. Three asymmetric cells connected in series illuminated the panel for about 45 minutes. All these results suggest that the synergistic integration of various efficient electrode materials leads to enhanced electrochemical performance of supercapacitors.

A critical review on orthosilicate Li2MSiO4(M = Fe, Mn) electrode materials for Li ion batteries.

The development of novel electrode materials with good electrochemical performances is necessary for the expanded and varied applications of lithium-ion batteries, and this development heavily relies on cathode materials. Due to excellent thermal stability, abundance, low cost, and environmental friendliness, orthosilicate cathode materials Li2MSiO4(M = Fe, Mn) has received a lot of attention recently. The present review article gives a glimpse into the characteristics, advantages, and recent progress of orthosilicate cathode materials. This review starts with a brief history and working mechanism of batteries, the advantages of cathode materials followed by types of cathode materials, various synthesis methods, and different techniques used for their characterization. The most current initiatives to enhance orthosilicate Li2MSiO4type electrochemical performances were introduced in this review. We provide a critical assessment of the efficient modification techniques for the orthosilicate Li2MSiO4type cathode materials in particular. These potential cathode materials' synthesis, structure, morphologies, and particularly electrochemical performances have been thoroughly examined. This evaluation, we hope, will clarify the sustained advancement of high-efficiency and reasonably priced Li-ion batteries.

Transition metal dichalcogenide (TMDs) electrodes for supercapacitors: a comprehensive review.

As globally, the main focus of the researchers is to develop novel electrode materials that exhibit high energy and power density for efficient performance energy storage devices. This review covers the up-to-date progress achieved in transition metal dichalcogenides (TMDs) (e.g. MoS2, WS2, MoSe2,and WSe2) as electrode material for supercapacitors (SCs). The TMDs have remarkable properties like large surface area, high electrical conductivity with variable oxidation states. These properties enable the TMDs as the most promising candidates to store electrical energy via hybrid charge storage mechanisms. Consequently, this review article provides a detailed study of TMDs structure, properties, and evolution. The characteristics technique and electrochemical performances of all the efficient TMDs are highlighted meticulously. In brief, the present review article shines a light on the structural and electrochemical properties of TMD electrodes. Furthermore, the latest fabricated TMDs based symmetric/asymmetric SCs have also been reported.

Structural, electrical properties and dielectric relaxations in Na+-ion-conducting solid polymer electrolyte.

In this paper, we have studied the structural, microstructural, electrical, dielectric properties and ion dynamics of a sodium-ion-conducting solid polymer electrolyte film comprising PEO8-NaPF6+ x wt. % succinonitrile. The structural and surface morphology properties have been investigated, respectively using x-ray diffraction and field emission scanning electron microscopy. The complex formation was examined using Fourier transform infrared spectroscopy, and the fraction of free anions/ion pairs obtained via deconvolution. The complex dielectric permittivity and loss tangent has been analyzed across the whole frequency window, and enables us to estimate the DC conductivity, dielectric strength, double layer capacitance and relaxation time. The presence of relaxing dipoles was determined by the addition of succinonitrile (wt./wt.) and the peak shift towards high frequency indicates the decrease of relaxation time. Further, relations among various relaxation times ([Formula: see text]) have been elucidated. The complex conductivity has been examined across the whole frequency window; it obeys the Universal Power Law, and displays strong dependency on succinonitrile content. The sigma representation ([Formula: see text]) was introduced in order to explore the ion dynamics by highlighting the dispersion region in the Cole-Cole plot ([Formula: see text]) in the lower frequency window; increase in the semicircle radius indicates a decrease of relaxation time. This observation is accompanied by enhancement in ionic conductivity and faster ion transport. A convincing, logical scheme to justify the experimental data has been proposed.

Profile of management of animal bite cases among rural population in district Pune, Maharashtra.

The study was carried out in three randomly selected Primary Health Centres (PHCs) of district Pune. During three months of study period all the patients with animal bite attending PHCs were enrolled for the study. All the animal bite cases (451) were due to dog bite and 61.4% were reported to be bitten by pet dogs. In spite of having the knowledge about seriousness of illness, immediate care like washing of wound with soap and water was practiced by only 23.5%. Majority of them did not report immediately to PHC for treatment after dog bite.

Synthesis and characterization of fluoro-substituted polyaniline.

Poly(2-fluoroaniline) was prepared by both chemical and electrochemical polymerization in acidic medium. Characterization of poly(2-fluoroaniline) was accomplished experimentally using ultraviolet-visible, Fourier transform infrared, differential scanning calorimetry, thermal gravimetric analysis, and X-ray diffraction techniques, respectively. Scanning electron microscopy studies revealed globular morphology of chemically synthesized poly(2-fluoroaniline). The cyclic voltammetric studies revealed diffusion-controlled phenomenon in electrochemically synthesized poly(2-fluoroaniline).

CAN WAIST/HIP RATIO BE USED AS A SIMPLE MEASURE OF CARDIOVASCULAR RISK IN THE ARMED FORCES : RESULTS FROM A FIELD EPIDEMIOLOGICAL STUDY.

A cross-sectional analytical epidemiologic study was undertaken in the community setting, on 1080 army personnel in a field formation, to study the association between waist/hip ratio (WHR) and certain physiological and biochemical parameters of cardiovascular risk. The study revealed that Junior Commissioned Officers, personnel aged 35 years and above, and personnel from Services had an increased probability of having higher WHR. WHR was consistently, linearly and significantly associated with increasing mean values of serum cholesterol, blood sugar and blood pressure. The optimum cut-off point of WHR from the findings of this study seems to be 0.91 and above. Beyond this value of WHR, the cardiovascular risk increases significantly and becomes more dramatic at WHR values of 0.96 and above.

ESTIMATES OF EX-SERVICEMEN POPULATION FOR NEXT 30 YEARS: A NEED TO REORIENT OUR HEALTH PLANNING.

A mathematical model, using survival analysis methods has been developed to estimate the total population as well as the populations as per specific age groups of ex-servicemen for the next 30 years. The results indicate that from the present population of 13.75 lakhs., the total population of ex-servicemen would be 15.62 lakhs by 2027 A.D. In addition, there are likely to be noteworthy changes in the population structure. While the population of geriatric age group (65 years and above) is only 21% at present compared to 49% from age group 45-54 years, by 2027 A.D. the geriatric age group would contribute to 34% of the ex-servicemen population while 45-54 years age group would constitute only 36%. There is a need, therefore, to start rethinking on our future plans as regards health services since geriatric health problems are likely to become a leading health issue after the next ten years.

EPIDEMIOLOGICAL STUDY OF ENTEROPATHOGENIC CARRIER STATE AMONG FOOD HANDLERS OF ARMED FORCES EATING ESTABLISHMENTS.

A cross-sectional epidemiological study was undertaken on a randomly selected sample of 308 food handlers working in different eating establishments of Indian Armed Forces in Pune. These included 101 Service personnel and 207 civilians. Stool samples were analysed for enteropathogens and epidemiological assessment of gastrointestinal disease occurrence in the military units of these food handlers was undertaken. The study revealed that 4 of the subjects were carriers of salmonella typhimurium, thus giving the prevalence as 1.3% (95% confidence interval 0.2% to 2.56%). No other enteropathogen except salmonella typhimurium was isolated. The positive carriers showed a typical "spatial - clustering" in that they were working in two geographically contiguous medical units.