Synthesis of CdS nanoparticles within thermally evaporated aerosol OT thin films

In this paper, we discuss the synthesis of cadmium sulfide (CdS) quantum dots within thermally evaporated sodium bis(2-ethylhexyl)sulfosuccinate (AOT) thin films. This procedure uses electrostatic interactions to entrap positively charged cadmium ions into thin films of the anionic surfactant AOT by a simple immersion of the film in electrolyte solution. Thereafter, the composite film is treated with H2S gas/Na2S solution resulting in the in-situ formation of CdS nanoparticles in the quantum size regime. It is believed that the ability of AOT molecules in the thermally evaporated thin films to form reverse micelles is responsible for the CdS nanoparticle size control observed. Investigation of the entrapment of cadmium ions in the AOT film and subsequent quantum dot synthesis was carried out by quartz crystal microgravimetry (QCM), UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) measurements

A study to estimate the knowledge and practice regarding safe sex among teenage girls attending a rural hospital

Background: This work was planned to assess knowledge about sexually transmitted diseases (STDs), contraceptive methods available and the practice of use of contraceptives and personal hygiene among teenage girls attending the outpatient department (OPD) of a rural medical college. Methods: Consenting, non-pregnant teenage girls (14-19 years) attending the gynaecology and obstetrics OPD with minor ailments were asked to respond to a questionnaire and blinded data collection was done by two lady counsellors. Statistical analysis was performed. Results: Knowledge of STI, unwanted pregnancy and family planning was significantly higher in teenage girls with sexual exposure, and in those who had completed standard 12 education (p<0.001).  Conclusions: Our work suggests that in this particular rural setting knowledge level of STD, HIV and unwanted pregnancy is high but practice of safe sex and contraceptives are low. We suggest implementation of age-appropriate gender based, culturally sensitive sex education curriculum in schools to cope up the increasing vulnerability of young girls. Additionally, community participation, health care institutions and media can raise awareness in teenage girls and their families and remove the taboo regarding family planning practices

Increasing Trends of Leptospirosis in Northern India: A Clinico-Epidemiological Study

Leptospirosis is often not suspected by physicians in patients with acute febrile illnesses reporting from supposedly “non-endemic areas,” including north India. Clinical manifestations are protean, and complications can affect most organ systems, including liver, kidneys, lungs, and the central nervous system. Timely diagnosis and specific therapy can reduce severity of illness and, in turn, mortality. In this study conducted at a tertiary care center in north India, we find how a much-neglected disease entity has emerged as a major cause of acute febrile illness in a so called “non-endemic area.” Incidence is increasing yearly. The majority of patients were from a rural background, and were farmers or farm labourers. Poor hygiene, contact with animals, rat infestation of houses, and contact with stagnant dirty water are the major determinants of disease. Apart from the usual symptoms of intermittent fever with chill and rigor, hepatosplenomegaly, renal decompensation, muscle pain and tenderness, and conjunctival suffusion, signs and symptoms indicating involvement of the respiratory and central nervous systems were also commonly observed. Severe complications resulting in mortality do occur and is especially due to late suspicion among primary level physicians, and the resulting inappropriate therapy

Mixing in planar spiral microchannel

The mixing characteristics in spiral microhannels are studied experimentally and numerically in this work. Effect of cross section aspect ratio (α = 0.3–1.2) on mixing characteristic is studied both qualitatively and quantitatively using top as well as side view details. The study is carried out for a wide range of Reynolds number (1–468) and Dean number (0.1–75). The pathline behavior and species fraction are tracked to understand the effect of Reynolds number and aspect ratio on mixing. It is observed that spiral microchannel with higher aspect ratio results in better mixing as compared to smaller aspect ratio microchannel. An optimal Reynolds number at which the mixing efficiency is maximized is observed from the experimental data. It is observed that the fluid is trapped within the vortex core at higher Reynolds number, leading to a reduction in mixing efficiency and appearance of a maxima. Frequent twisting of pathlines is further identified to affect mixing and leads to a dependence of mixing on aspect ratio. The analysis presented in this work is of significance in the design of spiral microchannel based microreactors

Electronic structure study of wide band gap magnetic semiconductor (La0.6Pr0.4)(0.65)Ca0.35MnO3 nanocrystals in paramagnetic and ferromagnetic phases

X-ray circular magnetic dichroism (XMCD), X-ray photoemission spectroscopy (XPS), and ultraviolet photoemission spectroscopy (UPS) techniques were used to study the electronic structure of nanocrystalline (La0.6Pr0.4)(0.65)Ca0.35MnO3 near Fermi-level. XMCD results indicate that Mn3+ and Mn4+ spins are aligned parallel to each other at 20 K. The low M-H hysteresis curve measured at 5K confirms ferromagnetic ordering in the (La0.6Pr0.4)(0.65)Ca0.35MnO3 system. The low temperature valence band XPS indicates that coupling between Mn3d and O2p is enhanced and the electronic states near Fermi-level have been suppressed below T-C. The valence band UPS also confirms the suppression of electronic states near Fermi-level below Curie temperature. UPS near Fermi-edge shows that the electronic states are almost absent below 0.5 eV (at 300K) and 1 eV (at 115K). This absence clearly demonstrates the existence of a wide band-gap in the system since, for hole-doped semiconductors, the Fermi-level resides just above the valence band maximum

Enhancement in electrical and magnetic properties with Ti-doping in Bi0.5La0.5Fe0.5Mn0.5O3

In this investigation, we have synthesized Bi0.5La0.5Fe0.5Mn0.5-xTixO3 (where x = 0 and 0.05) samples. The Rietveld refinement of X-ray diffraction (XRD) patterns shows that the systems crystallize in the orthorhombic phase with the Pnma space group. The observed Raman modes support the XRD results. The appearance of prominent A1-3 and weak E-2 modes in Bi0.5La0.5Fe0.5Mn0.45Ti0.05O3 indicates the presence of chemically more active Bi-O covalent bonds. Ferromagnetism of Bi0.5La0.5Fe0.5Mn0.5O3 is enhanced by Ti doping at the Mn-site, indicating that these particular samples might be interesting for device applications

Prevalence of HIV, hepatitis B and hepatitis C infections among patients with thalassemia attending a tertiary care (rural) hospital

Introduction: The Sunderban area of West Bengal is home to tribal and religious minorities inhabiting various islands. There is a high prevalence of thalassemia among poverty-stricken residents of this region living with meagre health care facilities. This work was planned to determine the proportion of four viral transfusion-transmitted infections (TTIs): HIV-1, HIV-2, hepatitis B virus (HBV) and hepatitis C virus (HCV) among thalassemia patients attending the sole rural medical college in the region. Materials and Methods: Thalassemia patients (n = 359, age ranging from 1 year to 60 years) attending the thalassemia clinic or being admitted to the indoor facilities for better management were included in the study. Only patients diagnosed with high-performance liquid chromatography (HPLC) and with classical clinical features were included in the study. Blood samples of these patients were tested for HIV as per NACO protocol. For HBV and HCV, samples were first tested serologically; reactive samples were collected and sent in the cold chain to a higher centre for nucleic acid amplification testing (NAAT) for qualitative and quantitative estimation. Clinical and laboratory data was collected, patients were followed up for complications and hospitalisation during the study period, and statistical analysis was performed. Results: Majority of our patients had E-beta-thalassemia (245, 59.81%), followed by beta-thalassemia major (102, 28.30%). NAAT-confirmed HCV infection (14.21%) infection was the most common, followed by HBV (2.51%), and lastly by HIV-1 (0.58%) infection. Among infected thalassemia patients, the mean HCV RNA was 741063 ± 438514.67 IU/ml while the mean HBV DNA level was 4082863 ± 7298514 IU/ml. Co-infections of HIV-1 and HCV and that of HBV and HCV were noted in one patient each (0.28%). HCV-related liver disease (14.21%) and growth retardation (10.31%) were the most typical complication noted, and death occurred in five patients (1.39%) during the study period. Conclusion: Primary care physicians should know HCV infection is the most common TTI among thalassemia patients in rural eastern India