Assessing the accuracy and reliability of satellite-derived precipitation products in the Kosi River basin (India).

The present research endeavors to examine the effectiveness of four gridded precipitation datasets, namely Integrated Multi-satellite Retrievals for GPM (IMERG), Tropical Precipitation Measuring Mission (TRMM), Modern-Era Retrospective Analysis for Research and Applications Version 2 (MERRA-2), and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN), with the observed rainfall data of eight rain gauge stations of India Meteorological Department (IMD) from 2001 to 2019 in Kosi River basin, India. Various statistical metrics, contingency tests, trend analysis, and rainfall anomaly index were utilized at daily, monthly, seasonal, and annual time scales. The categorical metrics namely probability of detection (POD) and false alarm ratio (FAR) indicate that MERRA-2 and IMERG datasets have the highest level of concurrence with the observed daily data. Statistical analysis of gridded datasets with observed dataset of IMD showed that the performance of the IMERG dataset is better than MERRA-2, PERSIANN, and TRMM datasets with "very good" coefficient of determination (R2) and Nash-Sutcliffe Efficiency values for monthly data. Trend analysis of gridded seasonal data of IMERG showed similar trends of observed seasonal data whereas other dataset differs. IMERG also performed well in identifying wet and dry years based on annual data. Discrepancies of the satellite sensor in capturing the precipitation have also been discussed. Thus, the IMERG dataset can be effectively used for hydro-meteorological and climatological investigations in cases of lack of observed datasets.

Selective gas detection of titania nanoparticles via impedance spectroscopy and capacitive measurement.

The present paper demonstrated the impedance analysis of Au/TiO2nanoparticles/Si-Al capacitive sensor for selective detection of volatile organic compounds (VOCs) at different frequency regimes. TiO2nanoparticles (NP) were synthesized through the solution process and characterized by field-emission scanning electron microscopy , x-ray diffraction analysis, photoluminescence spectroscopy, and atomic force microscopy. The gas sensitivity of Au/TiO2-NP/Si-Al was investigated, with the effect of temperature modulation (25 °C-250 °C) and dielectric variation in the vicinity of nanoparticles. Impedance spectroscopy of TiO2-NP was carried out to obtain resonant peaks over the frequency ranging from 0.05 to 225 kHz and fitted with a complex nonlinear least-squares method. The optimum sensor response of 136%, 63%, 152%, and 174% was found at resonant frequencies of 0.38 kHz, 0.22 kHz, 0.15 kHz, and 0.1 kHz for the exposure of 2-propanol, acetone, ethanol, and methanol, respectively. The fastest response time and recovery time were found to be 32/21 s, 31.2/8 s, 32.5/9 s, and 40/26 s for acetone, 2-propanol, ethanol, and methanol, respectively. Selective detection of different VOCs at various resonant frequencies has correlated with the dielectric variation of the NPs and their associated void region under gas exposure.

COVID-19 created chaos across the globe: Three novel quarantine epidemic models.

The latest version of human coronavirus said to be COVID-19 came out as a sudden pandemic disease within human population and in the absence of vaccination and proper treatment till date, it daunting threats heavily to human lives, infecting more than 12, 11, 214 people and death more than 67, 666 people in 208 countries across the globe as on April 06, 2020, which is highly alarming. When no treatment or vaccine is available till date and to avoid COVID-19 to be transmitted in the community, social distancing is the only way to prevent the disease, which is well taken into account in our novel epidemic models as a special compartment, that is, home isolation. Based on the transmitting behavior of COVID-19 in the human population, we develop three quarantine models of this pandemic taking into account the compartments: susceptible population, immigrant population, home isolation population, infectious population, hospital quarantine population, and recovered population. Local and global asymptotic stability is proved for all the three models. Extensive numerical simulations are performed to establish the analytical results with suitable examples. Our research reveals that home isolation and quarantine to hospitals are the two pivot force-control policies under the present situation when no treatment is available for this pandemic.

Autograft mitral valve replacement: a new technique.

We describe a new technique wherein we have used the Ionescu Ross Wooler stent for housing the pulmonary autograft. We believe that this technique is easy and reproducible and offers many advantages over the previously described techniques.

Structural differences between the SH3-HOOK-GuK domains of SAP90/PSD-95 and SAP97.

The SH3-HOOK-GUK domains of the postsynaptic scaffolding proteins SAP90/PSD-95 and SAP97 are established targets of synaptic plasticity processes in the brain. A crucial molecular mechanism involved is the transition of this domain to different conformational states. We purified the SH3-HOOK-GUK domain of both proteins to examine variations in protein conformation and stability. As monitored by circular dichroism and differential scanning calorimetry, SAP97 (T(m)=64 degrees C) is significantly more thermal stable than SAP90/PSD-95 (T(m)=52 degrees C) and follows a bimodal phase transition. GdmCl-induced equilibrium unfolding of both proteins follows the two-state transitions and thus does not involve the accumulation of stable intermediate state(s). Equilibrium unfolding of SAP97 is highly cooperative from a native state to an unfolded state. In contrast, SAP90/PSD-95 follows a non-cooperative transition from native to unfolded states. A highly cooperative unfolding reaction in case of SAP97 indicates that the protein existed initially as a compact, well-folded structure, while the gradual, non-cooperative melting reaction in case of SAP90/PSD-95 indicates that the protein is in comparison more flexible.