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The study's goal is to evaluate the phytosociology of several tree species in the Khonsa Forest Division. For the sample plots placed in the forest area underneath the research area, a random sampling design was used. For the calculation of different phyto-sociological attributes 40 identified tree species were found under <800m, 61 species were found under 800-1800m and 39 species were found under >1800m. The total density per hectare at 800m was 141.818 tree/hectare, 800-1800m was 215.360 tree/hectare, and >1800m was 235.926 tree/hectare. The Shannon Weiner's index was 2.390, 2.799, and 2.469 at 800m, 800m to 1800m, and >1800m, respectively. At 800m, 800-1800m, and 1800m, the species evenness of the study area was 0.652, 0.684, and 0.679 respectively. The Simpson index was 0.028, 0.019, and 0.023 at 800m, 800-1800m and >1800m respectively. It was found that at <800 m elevation, the highest IVI was in Terminalia myriocarpa (39.891) followed by Ailanthus integrifolia (30.085) and least in Artocarpus chaplasha (0.155). At elevation 800-1800m the highest IVI was in Schima wallichi (23.168) followed by Altingia excels (20.429) and least in Tetrameles nudiflora (0.127). The highest IVI at >1800m was in Magnolia champaca (28.893) followed by Schima wallichi (27.479) and least in Eleocarpus floribundus (0.211).

The study's goal is to evaluate the phytosociology of several tree species in the Khonsa Forest Division. For the sample plots placed in the forest area underneath the research area, a random sampling design was used. For the calculation of different phyto-sociological attributes 40 identified tree species were found under <800m, 61 species were found under 800-1800m and 39 species were found under >1800m. The total density per hectare at 800m was 141.818 tree/hectare, 800-1800m was 215.360 tree/hectare, and >1800m was 235.926 tree/hectare. The Shannon Weiner's index was 2.390, 2.799, and 2.469 at 800m, 800m to 1800m, and >1800m, respectively. At 800m, 800-1800m, and 1800m, the species evenness of the study area was 0.652, 0.684, and 0.679 respectively. The Simpson index was 0.028, 0.019, and 0.023 at 800m, 800-1800m and >1800m respectively. It was found that at <800 m elevation, the highest IVI was in Terminalia myriocarpa (39.891) followed by Ailanthus integrifolia (30.085) and least in Artocarpus chaplasha (0.155). At elevation 800-1800m the highest IVI was in Schima wallichi (23.168) followed by Altingia excels (20.429) and least in Tetrameles nudiflora (0.127). The highest IVI at >1800m was in Magnolia champaca (28.893) followed by Schima wallichi (27.479) and least in Eleocarpus floribundus (0.211).

Recent estimates suggest that up to 34% of frontline workers in healthcare (FLWs) at the forefront of the COVID-19 pandemic response are reporting elevated symptoms of psychological distress due to resource constraints, ineffective treatments, and concerns about self-contamination. However, little systematic research has been carried out to assess the mental health needs of FLWs in Europe, or the extent of psychological suffering in FLWs within different European countries of varying outbreak severity. Accordingly, this project will employ a mixed-methods approach over three work packages to develop best-practice guidelines for alleviating psychological distress in FLWs during the different phases of the pandemic. Work package 1 will identify the point and long-term prevalence of psychological distress symptoms in a sample of Irish and Italian FLWs, and the predictors of these symptoms. Work package 2 will perform a qualitative needs assessment on a sample of Irish and Italian FLWs to identify sources of stress and resilience, barriers to psychological care, and optimal strategies for alleviating psychological distress in relation to the COVID-19 pandemic. Work package 3 will synthesise the findings from the preceding work packages to draft best practice guidelines, which will be co-created by a multidisciplinary panel of experts using the Delphi method. The guidelines will provide clinicians with a framework for alleviating psychological distress in FLWs, with particular relevance to the COVID-19 pandemic, but may also have relevance for future pandemics and other public health emergencies.

BACKGROUND: Spirocerca lupi is a parasitic nematode of canids that can lead to a severe and potentially fatal disease. Recently, a new species, Spirocerca vulpis, was described from red foxes in Europe, suggesting a high genetic diversity of the Spirocerca spp. infecting canids. The genetic variation and phylogenetic relationships of S. lupi collected from naturally-infected domestic dogs from Australia, Hungary, Israel, Italy, India and South Africa, and S. vulpis from red foxes from Bosnia and Herzegovina, Italy and Spain, was studied using mitochondrial and rDNA markers. RESULTS: A high intra-individual variation was found in the first internal transcribed spacer (ITS1) locus in all Spirocerca spp., ranging between 0.37-2.84%, with up to six haplotypes per specimen. In addition, a combination of phylogenetic and haplotype analyses revealed a large variability between S. lupi specimens collected from different geographical locations using the ITS1 (0.37-9.33%) and the cytochrome c oxidase subunit 1 (cox1) gene (1.42-6.74%). This genetic diversity led to the identification of two S. lupi genotypes circulating among dogs (PTP support > 0.829), including genotype 1 found in S. lupi from Australia, India, Israel and South Africa, and genotype 2 represented by specimens from Hungary and Italy. These genotypes presented pairwise nucleotide distances of 0.14%, 8.06% and 6.48 ± 0.28% in the small rDNA subunit (18S), ITS1 and cox1 loci, respectively. Additionally, Nei's genetic distance in the ITS1 showed a further subdivision of genotype 1 worms into 1A (Israel and South Africa) and 1B (Australia and India). A morphological analysis of the anterior and posterior extremities of genotype 1 and genotype 2 worms using scanning electron microscopy did not show any differences between the specimens, contrary to the morphological differences between S. lupi and S. vulpis. CONCLUSIONS: These findings demonstrate the high genetic variability among Spirocerca spp. from different ge

Large Area X-ray Propositional Counter (LAXPC) instrument on AstroSat is aimed at providing high time resolution X-ray observations in 3 to 80 keV energy band with moderate energy resolution. To achieve large collecting area, a cluster of three co-aligned identical LAXPC detectors, is used to realize an effective area in access of about 6000 cm2 at 15 keV. The large detection volume of the LAXPC detectors, filled with xenon gas at about 2 atmosphere pressure, results in detection efficiency greater than 50%, above 30 keV. In this article, we present salient features of the LAXPC detectors, their testing and characterization in the laboratory prior to launch and calibration in the orbit. Some preliminary results on timing and spectral characteristics of a few X-ray binaries and other type of sources, are briefly discussed to demonstrate that the LAXPC instrument is performing as planned in the orbit., Comment: 11 pages, 15 Figures, Accepted for publication in Journal of Astronomy and Astrophysics

Large Area X-ray Propositional Counter (LAXPC) instrument on AstroSat is aimed at providing high time resolution X-ray observations in 3 to 80 keV energy band with moderate energy resolution. To achieve large collecting area, a cluster of three co-aligned identical LAXPC detectors, is used to realize an effective area in access of about 6000 cm2 at 15 keV. The large detection volume of the LAXPC detectors, filled with xenon gas at about 2 atmosphere pressure, results in detection efficiency greater than 50%, above 30 keV. In this article, we present salient features of the LAXPC detectors, their testing and characterization in the laboratory prior to launch and calibration in the orbit. Some preliminary results on timing and spectral characteristics of a few X-ray binaries and other type of sources, are briefly discussed to demonstrate that the LAXPC instrument is performing as planned in the orbit., Comment: 11 pages, 15 Figures, Accepted for publication in Journal of Astronomy and Astrophysics

The Soft X-ray focusing Telescope (SXT), India’s first X-ray telescope based on the principle of grazing incidence, was launched aboard the AstroSat and made operational on October 26, 2015. X-rays in the energy band of 0.3–8.0 keV are focussed on to a cooled charge coupled device thus providing medium resolution X-ray spectroscopy of cosmic X-ray sources of various types. It is the most sensitive X-ray instrument aboard the AstroSat. In its first year of operation, SXT has been used to observe objects ranging from active stars, compact binaries, supernova remnants, active galactic nuclei and clusters of galaxies in order to study its performance and quantify its characteriztics. Here, we present an overview of its design, mechanical hardware, electronics, data modes, observational constraints, pipeline processing and its in-orbit performance based on preliminary results from its characterization during the performance verification phase.

AstroSat is a multi-wavelength satellite launched on 2015 September 28. The CZT Imager of AstroSat on its very first day of operation detected a long duration gamma-ray burst (GRB) namely GRB 151006A. Using the off-axis imaging and spectral response of the instrument, we demonstrate that CZT Imager can localise this GRB correct to about a few degrees and it can provide, in conjunction with Swift, spectral parameters similar to that obtained from Fermi/GBM. Hence CZT Imager would be a useful addition to the currently operating GRB instruments (Swift and Fermi). Specifically, we argue that the CZT Imager will be most useful for the short hard GRBs by providing localisation for those detected by Fermi and spectral information for those detected only by Swift. We also provide preliminary results on a new exciting capability of this instrument: CZT Imager is able to identify Compton scattered events thereby providing polarisation information for bright GRBs. GRB 151006A, in spite of being relatively faint, shows hints of a polarisation signal at 100-300 keV (though at a low significance level). We point out that CZT Imager should provide significant time resolved polarisation measurements for GRBs that have fluence 3 times higher than that of GRB 151006A. We estimate that the number of such bright GRBs detectable by CZT Imager is 5 - 6 per year. CZT Imager can also act as a good hard X-ray monitoring device for possible electromagnetic counterparts of Gravitational Wave events., Comment: Submitted to ApJ

Charged Particle Monitor (CPM) on-board the AstroSat satellite is an instrument designed to detect the flux of charged particles at the satellite location. A Cesium Iodide Thallium (CsI(Tl)) crystal is used with a Kapton window to detect protons with energies greater than 1 MeV. The ground calibration of CPM was done using gamma-rays from radioactive sources and protons from particle accelerators. Based on the ground calibration results, energy deposition above 1 MeV are accepted and particle counts are recorded. It is found that CPM counts are steady and the signal for the onset and exit of South Atlantic Anomaly (SAA) region are generated in a very reliable and stable manner., Comment: 9 pages, 8 figures, 5 tables. To appear in JAA special issue on AstroSat

The Cadmium Zinc Telluride Imager (CZTI) is a high energy, wide-field imaging instrument on AstroSat. CZT's namesake Cadmium Zinc Telluride detectors cover an energy range from 20 keV to > 200 keV, with 11% energy resolution at 60 keV. The coded aperture mask attains an angular resolution of 17' over a 4.6 deg x 4.6 deg (FWHM) field of view. CZTI functions as an open detector above 100 keV, continuously sensitive to GRBs and other transients in about 30% of the sky. The pixellated detectors are sensitive to polarisation above ~100 keV, with exciting possibilities for polarisation studies of transients and bright persistent sources. In this paper, we provide details of the complete CZTI instrument, detectors, coded aperture mask, mechanical and electronic configuration, as well as data and products., Comment: 9 pages, 6 figures, 1 table. To appear in Astrosat special issue of the Journal of Astronomy and Astrophysics

Charged Particle Monitor (CPM) on-board the AstroSat satellite is an instrument designed to detect the flux of charged particles at the satellite location. A Cesium Iodide Thallium (CsI(Tl)) crystal is used with a Kapton window to detect protons with energies greater than 1 MeV. The ground calibration of CPM was done using gamma-rays from radioactive sources and protons from particle accelerators. Based on the ground calibration results, energy deposition above 1 MeV are accepted and particle counts are recorded. It is found that CPM counts are steady and the signal for the onset and exit of South Atlantic Anomaly (SAA) region are generated in a very reliable and stable manner., Comment: 9 pages, 8 figures, 5 tables. To appear in JAA special issue on AstroSat

AstroSat is a multi-wavelength satellite launched on 2015 September 28. The CZT Imager of AstroSat on its very first day of operation detected a long duration gamma-ray burst (GRB) namely GRB 151006A. Using the off-axis imaging and spectral response of the instrument, we demonstrate that CZT Imager can localise this GRB correct to about a few degrees and it can provide, in conjunction with Swift, spectral parameters similar to that obtained from Fermi/GBM. Hence CZT Imager would be a useful addition to the currently operating GRB instruments (Swift and Fermi). Specifically, we argue that the CZT Imager will be most useful for the short hard GRBs by providing localisation for those detected by Fermi and spectral information for those detected only by Swift. We also provide preliminary results on a new exciting capability of this instrument: CZT Imager is able to identify Compton scattered events thereby providing polarisation information for bright GRBs. GRB 151006A, in spite of being relatively faint, shows hints of a polarisation signal at 100-300 keV (though at a low significance level). We point out that CZT Imager should provide significant time resolved polarisation measurements for GRBs that have fluence 3 times higher than that of GRB 151006A. We estimate that the number of such bright GRBs detectable by CZT Imager is 5 - 6 per year. CZT Imager can also act as a good hard X-ray monitoring device for possible electromagnetic counterparts of Gravitational Wave events., Comment: Submitted to ApJ

The Cadmium Zinc Telluride Imager (CZTI) is a high energy, wide-field imaging instrument on AstroSat. CZT's namesake Cadmium Zinc Telluride detectors cover an energy range from 20 keV to > 200 keV, with 11% energy resolution at 60 keV. The coded aperture mask attains an angular resolution of 17' over a 4.6 deg x 4.6 deg (FWHM) field of view. CZTI functions as an open detector above 100 keV, continuously sensitive to GRBs and other transients in about 30% of the sky. The pixellated detectors are sensitive to polarisation above ~100 keV, with exciting possibilities for polarisation studies of transients and bright persistent sources. In this paper, we provide details of the complete CZTI instrument, detectors, coded aperture mask, mechanical and electronic configuration, as well as data and products., Comment: 9 pages, 6 figures, 1 table. To appear in Astrosat special issue of the Journal of Astronomy and Astrophysics

The interaction of Coccinella transversalis Fabricius and lschiodon scutellaris (Fabricius) with the aphid, Aphis craccivora Koch was studied on green gram by estimating the prey and predator populations at weekly interval. Populations of both the predators had positive correlation with the aphid, attaining population peak simultaneously with their prey. The population decline of the prey was followed by their predators.

The interaction of Coccinella transversalis Fabricius and lschiodon scutellaris (Fabricius) with the aphid, Aphis craccivora Koch was studied on green gram by estimating the prey and predator populations at weekly interval. Populations of both the predators had positive correlation with the aphid, attaining population peak simultaneously with their prey. The population decline of the prey was followed by their predators.

Ultra Violet Imaging Telescope on ASTROSAT Satellite mission is a suite of Far Ultra Violet (FUV; 130 to 180 nm), Near Ultra Violet (NUV; 200 to 300 nm) and Visible band (VIS; 320 to 550nm) imagers. ASTROSAT is a first multi wavelength mission of INDIA. UVIT will image the selected regions of the sky simultaneously in three channels & observe young stars, galaxies, bright UV Sources. FOV in each of the 3 channels is about 28 arc-minute. Targeted angular resolution in the resulting UV images is better than 1.8 arc-second (better than 2.0 arc-second for the visible channel). Two identical co-aligned telescopes (T1, T2) of Ritchey-Chretien configuration (Primary mirror of 375 mm diameter) collect the celestial radiation and feed to the detector system via a selectable filter on a filter wheel mechanism; gratings are available in the filter wheels of FUV and NUV channels for slit-less low resolution spectroscopy. The detector system for each of the 3 channels is generically identical. One telescope images in the FUV channel, and other images in NUV and VIS channels. One time open-able mechanical cover on each telescope also works as Sun-shield after deployment.We will present the optical tests and calibrations done on the two telescopes. Results on vibrations test and thermo-vacuum tests on the engineering model will also be presented., Comment: 9 pages, 7 figures, to be published in Proc. SPIE 8443, "Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray"

Ultra Violet Imaging Telescope on ASTROSAT Satellite mission is a suite of Far Ultra Violet (FUV; 130 to 180 nm), Near Ultra Violet (NUV; 200 to 300 nm) and Visible band (VIS; 320 to 550nm) imagers. ASTROSAT is a first multi wavelength mission of INDIA. UVIT will image the selected regions of the sky simultaneously in three channels & observe young stars, galaxies, bright UV Sources. FOV in each of the 3 channels is about 28 arc-minute. Targeted angular resolution in the resulting UV images is better than 1.8 arc-second (better than 2.0 arc-second for the visible channel). Two identical co-aligned telescopes (T1, T2) of Ritchey-Chretien configuration (Primary mirror of 375 mm diameter) collect the celestial radiation and feed to the detector system via a selectable filter on a filter wheel mechanism; gratings are available in the filter wheels of FUV and NUV channels for slit-less low resolution spectroscopy. The detector system for each of the 3 channels is generically identical. One telescope images in the FUV channel, and other images in NUV and VIS channels. One time open-able mechanical cover on each telescope also works as Sun-shield after deployment.We will present the optical tests and calibrations done on the two telescopes. Results on vibrations test and thermo-vacuum tests on the engineering model will also be presented., Comment: 9 pages, 7 figures, to be published in Proc. SPIE 8443, "Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray"

A low cost PC based real time data logging system can be used in the laboratories for the measurement, monitoring and storage of the data for slowly varying signals in science and engineering stream. This can be designed and interfaced to the PCs Parallel Port, which is common to all desktop computers or Personal Computers (PCs). By the use of this data logging system one can monitor, measure and store data for slowly varying signals, which is hard to visualise the signal waveforms by ordinary CRO (Cathode Ray Oscilloscope) and DSO (Digital Storage Oscilloscope). The data so stored can be used for further study and analysis. It can be used for a wide range of applications to monitor and store data of temperature, humidity, light intensity, ECG signals etc. with proper signal conditioning circuitry., Comment: Published in the Journal of Assam Science Society, December 2009

The present paper describes the design of a cost effective, better resolution data acquisition system (DAS) which is compatible to most of the PC and laptops. A low cost DAS has been designed using PIC12F675 having 4-channel analog input with 10-bit resolution for the monitoring of slowly varying signals. The DAS so designed is interfaced to the serial port of the PC. Firmware is written in Basic using Oshonsoft PIC IDE and burn to the microcontroller by using PICkit2 programmer. An application program is also developed using Visual Basic 6 which allows to display the waveform of the signal(s) and simultaneously the data also can be saved into the hard disk of the computer for future use and analysis., Comment: Published in the Journal of Instrument Society of India (ISOI)

Seasonal incidence of Plassey borer, Chilo tumidicostalis Hampson, and its larval parasitoid, Cotesia flavipes Cameron, was studied at Shillogani, Nagaon, Assam, during 2006-07. Population of C. tumidicostalis first appeared in the early part of May and peaked in the second fortnight of September in both the cropping seasons. Later it showed a declining trend till harvest. The activity of C. flavipes commenced from the first fortnight of June in both the cropping seasons and continued till the end of November, 2006 and early part of December, 2007. The extent of natural parasitism by C. flavipes varied from 2.10 to 39.43 per cent in 2006 and 1.33 to 48.30 per cent in 2007. Maximum parasitism (39.43 and 48.30 per cent) occurred during the first fortnight of October, 2006 and the second fortnight of September, 2007 in the two study years. The parasitism increased with the increase in incidence of C. tumidicostalis larvae and fairly synchronized with the latter's maximum incidence. The extent of parasitism had significant positive correlations with the incidence of host larval population and relative humidity, but showed non-significant correlations with temperature, total rainfall and sunshine in both the cropping seasons.

Seasonal incidence of Plassey borer, Chilo tumidicostalis Hampson, and its larval parasitoid, Cotesia flavipes Cameron, was studied at Shillogani, Nagaon, Assam, during 2006-07. Population of C. tumidicostalis first appeared in the early part of May and peaked in the second fortnight of September in both the cropping seasons. Later it showed a declining trend till harvest. The activity of C. flavipes commenced from the first fortnight of June in both the cropping seasons and continued till the end of November, 2006 and early part of December, 2007. The extent of natural parasitism by C. flavipes varied from 2.10 to 39.43 per cent in 2006 and 1.33 to 48.30 per cent in 2007. Maximum parasitism (39.43 and 48.30 per cent) occurred during the first fortnight of October, 2006 and the second fortnight of September, 2007 in the two study years. The parasitism increased with the increase in incidence of C. tumidicostalis larvae and fairly synchronized with the latter's maximum incidence. The extent of parasitism had significant positive correlations with the incidence of host larval population and relative humidity, but showed non-significant correlations with temperature, total rainfall and sunshine in both the cropping seasons.

Correlations that signal direct CP violation in the bottom sector are suggested. They need data on $Z\to b\bar b$ events which consist of a bottom hadron decay into an exclusive semileptonic channel $h \ell \nu $ (where $h$ is a hadron), and the other bottom hadron decay into a multi-body final state that manifests as a jet in the opposite hemisphere., Comment: 10 pages, Latex, no figures, expanded version

We study the EPR correlation implied by the entangled wavefunction of the $B^0\bar{B}^0$ pair created by the $\Upsilon $(4S) resonance. The analysis uses the basis provided by the mass eigenstates $B_1,B_2$ rather than the flavour states $B^0, \bar{B}^0$. Data on the inclusive dilepton charge ratio are close to the expectation of quantum mechanics, but nearly 8 standard deviations away from that of complete decoherence., Comment: 10 pages, Latex, no figures

Extraction of the mass difference $\Delta m$ from $B^0\bar B^0$ oscillations involves tagging of bottom flavour at production and at decay. We show that the asymmetry between the unmixed and mixed events factorizes into two parts, one depending on the production-tag and the other on the decay-tag., Comment: 6 pages, Latex, no figures

We study the EPR correlation implied by the entangled wavefunction of the $B^0\bar{B}^0$ pair created by the $\Upsilon $(4S) resonance. The analysis uses the basis provided by the mass eigenstates $B_1,B_2$ rather than the flavour states $B^0, \bar{B}^0$. Data on the inclusive dilepton charge ratio are close to the expectation of quantum mechanics, but nearly 8 standard deviations away from that of complete decoherence., Comment: 10 pages, Latex, no figures

Correlations that signal direct CP violation in the bottom sector are suggested. They need data on $Z\to b\bar b$ events which consist of a bottom hadron decay into an exclusive semileptonic channel $h \ell \nu $ (where $h$ is a hadron), and the other bottom hadron decay into a multi-body final state that manifests as a jet in the opposite hemisphere., Comment: 10 pages, Latex, no figures, expanded version

Extraction of the mass difference $\Delta m$ from $B^0\bar B^0$ oscillations involves tagging of bottom flavour at production and at decay. We show that the asymmetry between the unmixed and mixed events factorizes into two parts, one depending on the production-tag and the other on the decay-tag., Comment: 6 pages, Latex, no figures

We estimate the product of the relative strength of the $\Delta B = -\Delta Q$ amplitude in the decay $B_d^0 \rightarrow D^{*} \ell \bar \nu_{\ell }$ and the width-difference parameter $y$. For this we have used the data on time-dependence of $B_{d}^0\bar B_{d}^0$ oscillations in Z decays and the fraction of like-sign dilepton events at the $\Upsilon (4S)$., Comment: 8 pages, Latex, no figures

In order to detect the possible presence of $\Delta B = - \Delta Q$ amplitudes in neutral $B$ meson decays, we consider the measurement of decay time asymmetries involving like-sign dilepton events at the $B$ factories., Comment: 5 pages, latex, no figs

We estimate the product of the relative strength of the $\Delta B = -\Delta Q$ amplitude in the decay $B_d^0 \rightarrow D^{*} \ell \bar \nu_{\ell }$ and the width-difference parameter $y$. For this we have used the data on time-dependence of $B_{d}^0\bar B_{d}^0$ oscillations in Z decays and the fraction of like-sign dilepton events at the $\Upsilon (4S)$., Comment: 8 pages, Latex, no figures

In order to detect the possible presence of $\Delta B = - \Delta Q$ amplitudes in neutral $B$ meson decays, we consider the measurement of decay time asymmetries involving like-sign dilepton events at the $B$ factories., Comment: 5 pages, latex, no figs

The 1995 Nobel Prize in Physics is shared equally by the American physicists Frederick J. Reines and Martin L. Perl for their pioneering experimental contributions to lepton physics. Following is a brief account of their discoveries., Comment: 12 pages + 2 figures (supplied on request), latex, to appear in Current Science (Indian Academy of Sciences)

The 1995 Nobel Prize in Physics is shared equally by the American physicists Frederick J. Reines and Martin L. Perl for their pioneering experimental contributions to lepton physics. Following is a brief account of their discoveries., Comment: 12 pages + 2 figures (supplied on request), latex, to appear in Current Science (Indian Academy of Sciences)

This is a survey of the current experimental information on some of the interesting issues in neutrino physics: neutrino species, neutrino masses, neutrino magnetic moments, solar neutrinos, and the atmospheric neutrino anomaly., Comment: This version updates several experimental numbers, and includes an account of the model-independent determination of the solar neutrino fluxes leading to ${}^7$Be-neutrino suppression. The present version has no Fig. It is going to appear in IJMP A

This is a survey of the current experimental information on some of the interesting issues in neutrino physics: neutrino species, neutrino masses, neutrino magnetic moments, solar neutrinos, and the atmospheric neutrino anomaly., Comment: This version updates several experimental numbers, and includes an account of the model-independent determination of the solar neutrino fluxes leading to ${}^7$Be-neutrino suppression. The present version has no Fig. It is going to appear in IJMP A

We explore the possibility that the existing data on like-sign dileptons at the $\Upsilon (4S)$ resonance consist of events arising from $B_{d}^0 -\bar B_{d}^0$ mixing and also from $\Delta B = - \Delta Q$ transitions. The consequences of these nonstandard transitions for certain time-asymmetries which are likely to be measured at the $B$ factories are studied., Comment: {\LARGE \bf 10 pages, no figures, process using latex, TIFR/TH/93-50

Absract (Invited talk at the X DAE High Energy Physics symposium in December 1992, held at Tata Institute of Fundamental Research, Bombay), Comment: 20pages, TIFR/TH/93-16

We explore the possibility that the existing data on like-sign dileptons at the $\Upsilon (4S)$ resonance consist of events arising from $B_{d}^0 -\bar B_{d}^0$ mixing and also from $\Delta B = - \Delta Q$ transitions. The consequences of these nonstandard transitions for certain time-asymmetries which are likely to be measured at the $B$ factories are studied., Comment: {\LARGE \bf 10 pages, no figures, process using latex, TIFR/TH/93-50

Absract (Invited talk at the X DAE High Energy Physics symposium in December 1992, held at Tata Institute of Fundamental Research, Bombay), Comment: 20pages, TIFR/TH/93-16