ALBERT

Description: In this work, the impact of Air-Sea coupling on Tropical Cyclone (TC) predictions is studied using a 3-Dimensional Price-Weller-Pinkel (3DPWP) ocean model coupled to the Advanced Research WRF (ARW) in six tropical storms in the North Indian Ocean (NIO) representing different intensities, seasonality and varied oceanic conditions. A set of numerical experiments are conducted for each cyclone using SST boundary conditions derived GFS SST, NOAA/NCEP SST and ocean coupling (3DPWP). Significant differences and improvements are found in the predicted intensity and track in the simulations in which the cyclones' impact on SST is included. It has been found that while the uncoupled model using GFS SST considerably overestimated the intensity as well as produced large track errors, the ocean coupling substantially improved the track and intensity predictions. The improvements with 3DPWP are because of simulating the ocean-atmosphere feedback in terms of deepening of ocean mixed layer, reduction in enthalpy fluxes and storm induced SST cooling as seen in observations. The coupled model could simulate the cold wake in SST, asymmetries in the surface winds, enthalpy fluxes, size and structure of the storm in better agreement with observations than the uncoupled model. The coupled model reduced the track errors by roughly 0.3-39 % and intensity errors by 29-47 % at 24-96 h predictions by controlling the northward deviation of storms tracks by SST cooling and associated changes in the dynamics. The vorticity changes associated with horizontal advection and stretching terms affect the tracks of the storms in the three simulations.

Description: A novel scheme has been proposed by computational methods (B3LYP and CCSD(T)) to produce hydroxylamine under normal experimental conditions using [O 3 Re-(NH 2 )] and H 2 O 2 under basic conditions. This particular reaction may proceed similar to Baeyer–Villiger oxidation and μ -peroxo type pathways to insert oxygen into the Re NH 2 bond to yield NH 2 OH; nevertheless, Baeyer–Villiger type oxidation is seems to be more viable. The calculated energy barriers further revealed that the introduction of different solvent medium does not affect significantly the energies of intermediates and transition state molecules. The calculated Gibbs free energies show that this reaction is perhaps viable experimentally to produce NH 2 OH from the our choice of reagents. Copyright © 2015 John Wiley & Sons, Ltd. A new method has been proposed by density functional calculations to produce hydroxylamine at room temperature and one atmospheric pressure using [O 3 Re-(NH 2 )] and H 2 O 2 under basic conditions. This reaction may proceed similar to the Baeyer-Villiger (BV) oxidation and µ-peroxo type pathways to insert oxygen into the Re-NH 2 bond to yield NH 2 OH. The calculated Gibbs free energies show that this reaction may be viable experimentally to produce NH 2 OH.

Description: “Mobile mud” (MM) which has fine grain-size distribution (〉 90% clay + silt, and 〈 5% sand) and high porosity (≥ 0.50), plays an important role in the biogeochemical cycles in the estuarine areas and the inshore shelf. A suite of MM samples from the coastal area of the East China Sea (ECS) was collected in spring and summer of 2011 to observe their spatial and temporal distribution, grain-size and radionuclides concentrations. The MM thickness ranged from 0.5 to 11 cm (average: 2.2 cm (May) and 3.9 cm (August)). The thick mud layer is mainly distributed along the coast, with an area of 2.2 × 10 4 km 2 in May and 1.5 × 10 4 km 2 in August, with corresponding masses of 8.8 × 10 8 ton and 7.8 × 10 8 ton, respectively. The estimated masses of MM are considerably larger than the annual sediment discharge mass of the Changjiang River. The distribution of 137 Cs inventories in MM indicate that 137 Cs can be effectively utilized as a transport tracer of MM in the river-dominated estuaries and coastal areas. The higher inventories of 7 Be in MM in the river mouth in spring are attributed to higher depositional flux and higher sediment discharge. The ratio of the MM inventory of 234 Th ex /production in the overlying water column of 〉 2.5 in south inshore indicates that the sediment focusing resulted in the increased mass flux. The residence time of MM is estimated as 3-6 years both by mass balance of MM and 210 Pb ex in MM . This article is protected by copyright. All rights reserved.

Description: In this study, the performance of the weather research and forecasting (WRF) ARW regional model was evaluated for simulating the regional scale precipitation during Indian summer monsoon (ISM) at 30 km resolution over seven different homogeneous rainfall zones falling under different climatic (perhumid, humid, dry/moist subhumid, dry/moist semiarid, arid) regions of India. Seasonal scale simulations were made for ten summers (JJAS months) over 2000-2009 using the boundary conditions derived from the National Centers for Environmental Prediction (NCEP) reanalysis data. Sensitivity experiments were conducted with three convection schemes (Kain-Fritsch, KF; Betts-Millor-Janjic, BMJ; Grell-Devenyi, GD). Simulated regional climate was evaluated by comparison of precipitation with 0.5° India Meteorological Department (IMD) gridded rainfall data over land, Tropical Rainfall Measuring Mission (TRMM) rainfall data over the ocean and atmospheric circulation fields with 1° NCEP global final analysis (FNL). Although all the simulations showed spatio-temporal rainfall patterns, BMJ had least bias towards dryness whereas KF had moist bias and GD had higher dry bias. BMJ could simulate low, moderate and high rainfall reasonably well with relatively higher correlations and threat scores, lower bias and mean absolute errors in most zones as compared to better simulation of heavy precipitation events with KF and low rainfall days alone with GD scheme. The better performance of BMJ scheme is evident owing to better simulation of surface pressure, temperature, and geopotential, lower and upper atmospheric flow fields. Simulations revealed a relatively less intensive heat, weaker low-level westerly winds, weaker north-south geopotential gradients, weaker subtropical easterlies in the El Niño years than in the La Niña years, which indicate the model is able to simulate the interannual variations in monsoon characteristics. Copyright © 2012 Royal Meteorological Society

Description: Excess nutrients from agriculture in the Mississippi River drainage, USA have degraded water quality in freshwaters and contributed to anoxic conditions in downstream estuaries. Consequently, water quality is a significant concern associated with conversion of lands to bioenergy production. This study focused on the Arkansas-White-Red river basin (AWR), one of five major river basins draining to the Mississippi River. The AWR has a strong precipitation gradient from east to west, and advanced cellulosic feedstocks are projected to become economically feasible within normal-to-wet areas of the region. In this study, we used large-scale watershed modeling to identify areas along this precipitation gradient with potential for improving water quality. We compared simulated water quality in rivers draining projected future landscapes with and without cellulosic-bioenergy for two future years, 2022 and 2030 with an assumed farmgate price of $50 per dry ton. Changes in simulated water quantity and quality under future bioenergy scenarios varied among subbasins and years. Median water yield, nutrient loadings, and sediment yield decreased by 2030. Median concentrations of nutrients also decreased, but suspended sediment, which is influenced by decreased flow and in-stream processes, increased. Spatially, decreased loadings prevailed in the transitional ecotone between 97° and 100° longitude, where switchgrass, Panicum virgatum L ., is projected to compete against alternative crops and land uses at $50 per dry ton. We conclude that this region contains areas that hold promise for sustainable bioenergy production in terms of both economic feasibility and water-quality protection. This article is protected by copyright. All rights reserved.

Description: Bulk depositional fluxes of 7Be and 210Pb in precipitation measured over a period of 16 months (April 2009–July 2010) in Huelva, Spain varied between 5.6 and 186 Bq m−2 month−1 (annual mean: 834 Bq m−2 year−1) and 0.8 and 8.1 Bq m−2 month−1 (annual mean: 59 Bq m−2 year−1), respectively, with the lowest depositional fluxes occurring during dry summer months. Quantitative evaluation of the precipitation-normalized seasonal depositional fluxes of 7Be and 210Pb indicates that the enrichment factor in winter is 〈 1.0 while in 2010 spring, it is significantly higher than 1, possibly indicating input of air from the stratosphere-troposphere exchange (for 7Be). The specific activities of 7Be and 210Pb varied from 0.03 to 7.42 Bq L−1 (mean = 2.5 Bq L−1) and 0.005 to 1.07 BqL−1 (mean = 0.23 Bq L−1), respectively, with the highest values corresponding to the spring season. The spatial and temporal variations of 7Be and 210Pb in aerosols from three stations are evaluated and compared to their monthly depositional fluxes. The mean depositional velocity of aerosols using 7Be and 210Pb are similar, ∼0.5 cm s−1 and are compared to other published values. This is the first time the fractional amounts of 7Be and 210Pb in monthly bulk precipitation are compared to the fractional amount of precipitation and provides insight on how the amount of precipitation plays a key role on the scavenging of these nuclides. The importance of dry fallout is evaluated for the study site which has direct implications for other areas in the Mediterranean Climate Zone.

Description: 7 Be and 210 Pb, two atmospherically delivered radionuclides, have been broadly applied to study the processes including air mass transport, soil erosion and particle cycling in aqueous systems. These studies require temporal variations of their depositional fluxes. In the present work, monthly atmospheric bulk depositional fluxes of 7 Be and 210 Pb were measured over 8 years (December 2005 to December 2013) at Shanghai, China. The bulk depositional fluxes of 7 Be and 210 Pb varied from 17.9 to 421 Bq m -2 month -1 and 6.8 to 82.1 Bq m -2 month -1 , respectively. The volume-weighted activities ranged from 0.20 to 8.06 Bq L -1 for 7 Be and 0.05 to 3.40 Bq L -1 for 210 Pb. There were strong seasonal variations in the depositional fluxes of these nuclides. The seasonal fraction of depositional fluxes was 〉30% of the total annual depositional fluxes of 210 Pb in winter and 7 Be in spring. The lowest depositional fluxes were found in summer for both radionuclides, with precipitation-normalized enrichment factor ( α ) values of 〈 1.0. The results from the synthesis of global fallout data indicate that there are latitudinal variations in the maximum depositional fluxes and volume-weighted activities of 7 Be, both values increase with latitude from the equator to the mid-latitudes. The 210 Pb depositional fluxes increase with the distance from the coast in inland regions (distance from the coast 〉 50 km) and increase with the amount of precipitation in onshore region (distance from the coast ≤ 50 km).We also report that Shanghai, China has the second highest bulk depositional fluxes of 210 Pb in literature.

Description: Food webs and associated elemental cycles in the Laurentian Great Lakes have been considerably altered over the past 30 years due to factors such as phosphorus abatement, introduction of zebra and quagga mussels, and climate change. These perturbations provide a unique opportunity to document how this natural system has responded and possibly to predict future changes in biogeochemical cycling.

Description: ABSTRACT Doxorubicin (DOX) induced cardiotoxicity is a major problem during chemotherapy of cancers. DOX–mediated suppression of type 1 IGF receptor (IGF-1R) signaling leads to cardiac dysfunction. Neferine, a bisbezylisoquinoline alkaloid from the seed embryos of Nelumbo nucifera Gaertn possesses a distinct range of pharmacological properties. Herewith, the present study attempts to elucidate the protective role of neferine against DOX induced toxicity in H9c2 rat cardiomyoblast cell line model. DOX-treated H9c2 cells significantly increased mitochondrial superoxide generation, depleted cellular antioxidant status, suppressed the activation of IGF-1R signaling via PI3K/Akt/mTOR and induced autophagy by the activation of ULK1, Beclin1, Atg7 and LC3B. Neferine pre-treatment activated IGF-1R signaling, improved cellular antioxidant pool, increased the expression of down-stream targets of IGF-1R, such as PI3K/Akt/mTOR, inhibited mitochondrial superoxide generation and autophagy significantly with the induction of Nrf2 translocation and expressions of HO1 and SOD1. Our study suggests the use of neferine for amelioration of DOX-mediated cardiotoxicity. This article is protected by copyright. All rights reserved