We present the photometric calibration of the Swift Ultraviolet/Optical Telescope (UVOT) which includes: optimum photometric and background apertures, effective area curves, colour transformations, ...conversion factors for count rates to flux and the photometric zero-points (which are accurate to better than 4 per cent) for each of the seven UVOT broad-band filters. The calibration was performed with observations of standard stars and standard star fields that represent a wide range of spectral star types. The calibration results include the position-dependent uniformity, and instrument response over the 1600–8000 Å operational range. Because the UVOT is a photon-counting instrument, we also discuss the effect of coincidence loss on the calibration results. We provide practical guidelines for using the calibration in UVOT data analysis. The results presented here supersede previous calibration results.
Changes in rainfall affect drinking water, river and surface runoff, soil moisture, groundwater reserve, electricity generation, agriculture production and ultimately the economy of a country. Trends ...in rainfall, therefore, are important for examining the impact of climate change on water resources for its planning and management. Here, as analysed from 119 years of rainfall measurements at 16 different rain gauge stations across northeast India, a significant change in the rainfall pattern is evident after the year 1973, with a decreasing trend in rainfall of about 0.42 ± 0.024 mm dec−1. The wettest place of the world has shifted from Cherrapunji (CHE) to Mawsynram (MAW) (separated by 15 km) in recent decades, consistent with long-term rainfall changes in the region. The annual mean accumulated rainfall was about 12 550 mm at MAW and 11 963 mm at CHE for the period 1989-2010, as deduced from the available measurements at MAW. The changes in the Indian Ocean temperature have a profound effect on the rainfall in the region, and the contribution from the Arabian Sea temperature and moisture is remarkable in this respect, as analysed with a multivariate regression procedure for the period 1973-2019. The changes in land cover are another important aspect of this shift in rainfall pattern, as we find a noticeable reduction in vegetation area in northeast India in the past two decades, implying the human influence on recent climate change.
Gamma-ray bursts (GRBs) are flashes of high-energy radiation arising from energetic cosmic explosions. Bursts of long (greater than two seconds) duration are produced by the core-collapse of massive ...stars
, and those of short (less than two seconds) duration by the merger of compact objects, such as two neutron stars
. A third class of events with hybrid high-energy properties was identified
, but never conclusively linked to a stellar progenitor. The lack of bright supernovae rules out typical core-collapse explosions
, but their distance scales prevent sensitive searches for direct signatures of a progenitor system. Only tentative evidence for a kilonova has been presented
. Here we report observations of the exceptionally bright GRB 211211A, which classify it as a hybrid event and constrain its distance scale to only 346 megaparsecs. Our measurements indicate that its lower-energy (from ultraviolet to near-infrared) counterpart is powered by a luminous (approximately 10
erg per second) kilonova possibly formed in the ejecta of a compact object merger.
In the present simulation, the study theoretically investigates the effect of temperature on the bandgaps of a 1D superconductor‐dielectric photonic crystal with different thicknesses of the ...semiconducting layer, for a fixed lattice parameter d. For this study, the alternate layers of superconductor and dielectric materials are taken as the SPC. In this work, 3D transmission spectra of the SPC against wavelength and temperature is plotted, for three chosen values of the thickness of the semiconducting layer. The study finds that, an increase in temperature causes enlargement in the two bandgaps obtained for a fixed thickness of the semiconducting layer, while there is less impact of temperature on the first bandgap. On the other hand, the study notices that a decrease in the thickness of the semiconducting layer decreases these two obtained enlarged bangaps. Hence, it is demonstrated that temperature and semiconducting layer thickness are the controlling factors for the bandgap widths, and these two parameters also tune the band locations, particularly of the second band obtained in higher wavelength range. This analysis can be employed in designing bandgap based temperature sensors and in switching devices.
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•Graft co-polymer of DADMAC has been synthesized by microwave assisted synthesis.•The novel graft co-polymer was characterized by various phycio- chemical characterization techniques ...namely FTIR, Elemental analysis, SEM, TGA, DTA and XRD.•The general flocculation efficacy of the novel graft co-polymer was studied in various suspensions namely (1%) coal fine, (0.25%) kaolin, municipal waste water, river water and in (0.25%) multi-walled carbon nano-tubes (MWCNT) towards application as ‘Nano-hunters’.
The search for a sustainable and nontoxic polymeric product has fired an intense research in the field of graft copolymers. This study endeavor to create a polyacrylamide free novel flocculant which showed efficient behavior towards water and wastewater treatment and for mineral ore beneficiation. We synthesized the novel graft copolymer - Poly Diallyl Dimethyl Ammonium Chloride (DADMAC) grafted polyvinyl pyrrolidone (PVP-g-pDADMAC) via graft polymerization route by microwave assisted method. The synthesized novel cationic graft co-polymer has been characterized by elemental analysis, FTIR spectroscopy, intrinsic viscosity measurement, molecular weight determination, and scanning electron micrograph (SEM), taking PVP as reference. The effects of reaction parameters onto the percentage grafting have been studied. The applicability of these grafted polymers as flocculant for the treatment of municipal sewage waste water as well as for mineral ore beneficiation and for suppression of nanopollutant like multi-walled carbon Nano-tubes (MWCNTs) (as nano scavenger) from water systems were also investigated.
The research endeavour to synthesize a novel, non-toxic, eco-friendly guar gum based biopolymeric macromolecule, 2-(methacryloyloxy) ethyl trimethyl ammonium chloride grafted guar gum (GG-g-P ...(MAETMAC)) that has been optimized as a flocculant for mineral ore processing. The synthesis was performed using non-radiation and microwave assisted technique to compare and ensure the superiority of the latter. The intended grafting of monomer2-(methacryloyloxy) ethyl trimethyl ammonium chloride on to the biological macromolecule (guar gum) was confirmed through standard physico-chemical characterization techniques namely X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV–visible) spectroscopy, intrinsic viscosity study, etc. The flocculation efficacy of the synthesized novel graft copolymer was thoroughly investigated in kaolin, coal fine, and iron ore suspensions. We have explored a graft copolymer, 2-(methacryloyloxy) ethyl trimethyl ammonium chloride grafted guar gum that has not been studied yet to the best of our knowledge. To establish the superiority of the synthesized biomaterial, the flocculation study revealed that the best grade of the synthesized novel graft copolymer showed flocculation efficacy of 90 % in kaolin, 69 % in Iron ore, and 29 % in coal fine suspensions which was significantly higher than using alum as a coagulant which provided 36 % efficacy in kaolin, 29 % in iron ore and 10 % in coal fine suspensions.
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•A guar gum based novel biopolymeric macromolecule was synthesized.•The microwave-assisted synthesis technique is superior to non-radiation methods.•The novel graft copolymer acts as a flocculant towards mineral ore processing.•The synthesized graft copolymer showed 90 % flocculation in kaolin suspension.
Summary
VRC‐HIVMAB060‐00‐AB (VRC01) is a broadly neutralizing HIV‐1 monoclonal antibody (mAb) isolated from the B cells of an HIV‐infected patient. It is directed against the HIV‐1 CD4 binding site ...and is capable of potently neutralizing the majority of diverse HIV‐1 strains. This Phase I dose‐escalation study in healthy adults was conducted at the National Institutes of Health (NIH) Clinical Center (Bethesda, MD, USA). Primary objectives were the safety, tolerability and pharmacokinetics (PK) of VRC01 intravenous (i.v.) infusion at 5, 20 or 40 mg/kg, given either once (20 mg/kg) or twice 28 days apart (all doses), and of subcutaneous (s.c.) delivery at 5 mg/kg compared to s.c. placebo given twice, 28 days apart. Cumulatively, 28 subjects received 43 VRC01 and nine received placebo administrations. There were no serious adverse events or dose‐limiting toxicities. Mean 28‐day serum trough concentrations after the first infusion were 35 and 57 μg/ml for groups infused with 20 mg/kg (n = 8) and 40 mg/kg (n = 5) doses, respectively. Mean 28‐day trough concentrations after the second infusion were 56 and 89 μg/ml for the same two doses. Over the 5–40 mg/kg i.v. dose range (n = 18), the clearance was 0·016 l/h and terminal half‐life was 15 days. After infusion VRC01 retained expected neutralizing activity in serum, and anti‐VRC01 antibody responses were not detected. The human monoclonal antibody (mAb) VRC01 was well tolerated when delivered i.v. or s.c. The mAb demonstrated expected half‐life and pharmacokinetics for a human immunoglobulin G. The safety and PK results support and inform VRC01 dosing schedules for planning HIV‐1 prevention efficacy studies.
Summary
Guidelines for doctors managing osteoporosis in the Asia-Pacific region vary widely. We compared 18 guidelines for similarities and differences in five key areas. We then used a structured ...consensus process to develop clinical standards of care for the diagnosis and management of osteoporosis and for improving the quality of care.
Purpose
Minimum clinical standards for assessment and management of osteoporosis are needed in the Asia-Pacific (AP) region to inform clinical practice guidelines (CPGs) and to improve osteoporosis care. We present the framework of these clinical standards and describe its development.
Methods
We conducted a structured comparative analysis of existing CPGs in the AP region using a “5IQ” model (identification, investigation, information, intervention, integration, and quality). One-hundred data elements were extracted from each guideline. We then employed a four-round Delphi consensus process to structure the framework, identify key components of guidance, and develop clinical care standards.
Results
Eighteen guidelines were included. The 5IQ analysis demonstrated marked heterogeneity, notably in guidance on risk factors, the use of biochemical markers, self-care information for patients, indications for osteoporosis treatment, use of fracture risk assessment tools, and protocols for monitoring treatment. There was minimal guidance on long-term management plans or on strategies and systems for clinical quality improvement. Twenty-nine APCO members participated in the Delphi process, resulting in consensus on 16 clinical standards, with levels of attainment defined for those on identification and investigation of fragility fractures, vertebral fracture assessment, and inclusion of quality metrics in guidelines.
Conclusion
The 5IQ analysis confirmed previous anecdotal observations of marked heterogeneity of osteoporosis clinical guidelines in the AP region. The Framework provides practical, clear, and feasible recommendations for osteoporosis care and can be adapted for use in other such vastly diverse regions. Implementation of the standards is expected to significantly lessen the global burden of osteoporosis.
The India’s annual milk and ghee production are approximately estimated as 160 MT and 1.72 MT respectively. India has the largest production of Ghee in the dairy Industry worldwide. Ghee consumption ...in India is 28% annually after fluid milk i.e. 44% due to high consumer demand. The butter churner, butter melter, ghee boiler and ghee clarifier are the key subunits of ghee production plant. The dairy industry is characterised by high energy consumption for production of Ghee and Butter in the country. The thermo-economic analysis and thermodynamic derivatives calculated in this study. The value of the universal exergy efficiency and specific exergy destruction of the plant was found as 34.21% and 438.61 kJ/kg respectively. The cost rate of exergy destruction for the entire plant was calculated as 3270.68 R/H; 39% of which was contributed by boiler for ghee production (ghee boiler). The highest value of percentage relative cost difference was associated with butter melter (97.29%) followed by butter churner (96.73%). The thermo-economic factor butter churner (8.00%) and ghee boiler (1.09%) revealed that impact of capital investment was more influential in former while exergetic degradation appeared to be more noticeable in latter.
•Exergy Efficiency of the plant was performed in this work.•Thermo-economic analysis of ghee production plant studied on actual plant data.•The Specific Exergy Destruction of plant ascertained to be 438.61 kJ/kg.•The Specific Exergy Improvement Potential of plant estimated as 314.26 kJ/kg.•Total plant operating cost and specific manufacturing cost of Ghee is calculated.
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