First-principles quantum transport modeling of thermoelectricity in single-molecule nanojunctions with graphene nanoribbon electrodes

We overview nonequilibrium Green function combined with density functional theory (NEGF-DFT) modeling of independent electron and phonon transport in nanojunctions with applications focused on a new class of thermoelectric devices where a single molecule is attached to two metallic zigzag graphene nanoribbons (ZGNRs) via highly transparent contacts. Such contacts make possible injection of evanescent wavefunctions from ZGNRs, so that their overlap within the molecular region generates a peak in the electronic transmission. Additionally, the spatial symmetry properties of the transverse propagating states in the ZGNR electrodes suppress hole-like contributions to the thermopower. Thus optimized thermopower, together with diminished phonon conductance through a ZGNR/molecule/ZGNR inhomogeneous structure, yields the thermoelectric figure of merit ZT~0.5 at room temperature and 0.5<ZT<2.5 below liquid nitrogen temperature. The reliance on evanescent mode transport and symmetry of propagating states in the electrodes makes the electronic-transport-determined power factor in this class of devices largely insensitive to the type of sufficiently short conjugated organic molecule, which we demonstrate by showing that both 18-annulene and C10 molecule sandwiched by the two ZGNR electrodes yield similar thermopower. Thus, one can search for molecules that will further reduce the phonon thermal conductance (in the denominator of ZT) while keeping the electronic power factor (in the nominator of ZT) optimized. We also show how often employed Brenner empirical interatomic potential for hydrocarbon systems fails to describe phonon transport in our single-molecule nanojunctions when contrasted with first-principles results obtained via NEGF-DFT methodology.Comment: 20 pages, 6 figures; mini-review article prepared for the special issue of the Journal of Computational Electronics on "Simulation of Thermal, Thermoelectric, and Electrothermal Phenomena in Nanostructures", edited by I. Knezevic and Z. Aksamij

Psychosocial Treatment of Children in Foster Care: A Review

A substantial number of children in foster care exhibit psychiatric difficulties. Recent epidemiologi-cal and historical trends in foster care, clinical findings about the adjustment of children in foster care, and adult outcomes are reviewed, followed by a description of current approaches to treatment and extant empirical support. Available interventions for these children can be categorized as either symptom-focused or systemic, with empirical support for specific methods ranging from scant to substantial. Even with treatment, behavioral and emotional problems often persist into adulthood, resulting in poor functional outcomes. We suggest that self-regulation may be an important mediat-ing factor in the appearance of emotional and behavioral disturbance in these children

Randomized Trial of Metformin, Ivermectin, and Fluvoxamine for Covid-19

BACKGROUND Early treatment to prevent severe coronavirus disease 2019 (Covid-19) is an important component of the comprehensive response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. METHODS In this phase 3, double-blind, randomized, placebo-controlled trial, we used a 2-by-3 factorial design to test the effectiveness of three repurposed drugs - metformin, ivermectin, and fluvoxamine - in preventing serious SARS-CoV-2 infection in nonhospitalized adults who had been enrolled within 3 days after a confirmed diagnosis of infection and less than 7 days after the onset of symptoms. The patients were between the ages of 30 and 85 years, and all had either overweight or obesity. The primary composite end point was hypoxemia (≤93% oxygen saturation on home oximetry), emergency department visit, hospitalization, or death. All analyses used controls who had undergone concurrent randomization and were adjusted for SARSCoV-2 vaccination and receipt of other trial medications. RESULTS A total of 1431 patients underwent randomization; of these patients, 1323 were included in the primary analysis. The median age of the patients was 46 years; 56% were female (6% of whom were pregnant), and 52% had been vaccinated. The adjusted odds ratio for a primary event was 0.84 (95% confidence interval [CI], 0.66 to 1.09; P=0.19) with metformin, 1.05 (95% CI, 0.76 to 1.45; P=0.78) with ivermectin, and 0.94 (95% CI, 0.66 to 1.36; P=0.75) with fluvoxamine. In prespecified secondary analyses, the adjusted odds ratio for emergency department visit, hospitalization, or death was 0.58 (95% CI, 0.35 to 0.94) with metformin, 1.39 (95% CI, 0.72 to 2.69) with ivermectin, and 1.17 (95% CI, 0.57 to 2.40) with fluvoxamine. The adjusted odds ratio for hospitalization or death was 0.47 (95% CI, 0.20 to 1.11) with metformin, 0.73 (95% CI, 0.19 to 2.77) with ivermectin, and 1.11 (95% CI, 0.33 to 3.76) with fluvoxamine. CONCLUSIONS None of the three medications that were evaluated prevented the occurrence of hypoxemia, an emergency department visit, hospitalization, or death associated with Covid-19

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Not AvailableA study on water quality of FCV tobacco growing areas of Tanguturu mandal under Southern Black Soils of Prakasam district was undertaken to explore and assess the water quality in order to develop different spatial maps of water quality to know the distribution and classify the available ground water suitable for irrigation with the help of Water quality Index (WQI) values calculated. The study area mostly black and mixed type of black and red soils. The pH of irrigation water in the study area was slightly alkaline to alkaline. The spatial thematic maps showed that ground water pH and chlorides in most of the area was in the range of 8.0-8.5 and 1.0 – 10.0 meq /l, respectively. While, bi-carbonate concentration of most of the study area ranged between 2.0 and 4.0 meq/l. Dominating ion is chloride in the system and following an order of Chlorides > Sodium> Bicarbonates > Carbonates > Potassium. Relatively high potassium (2.36 meq/l) was found in ground water in few villages which certainly help in better quality FCV tobacco. The major irrigation water quality class of the study area was moderately suitable (60 %) followed by suitable (14 %) with respect to FCV tobacco based on water quality index values developed. Conjunctive use of ground water and harvested rainwater is the effective way of utilisation of available ground water resource in the study area for FCV tobacco cultivationNot Availabl

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Not AvailableNatural resources (land and water) in 17 villages of Kandukur (15007’01.17 to 15019’40.0 N latitude and 79050’26.35 to 79058’39.32 E longitude) mandal was recorded during transect of the area and ground water sampling. Land forms are uplands, low lands, river alluviums and uncultivated barren lands. Soil type varied with different land forms and the area is a conglomerate of red, black and mixed soils. Red sandy loams to sandy clay loams are in uplands. Black clay loams to clay in lowlands spread over villages of Machavaram, Dondapadu, Mopadu and Anandapuram. Some patches are seen with mixed soils. Some lands in Vikkiralapeta, Pandulapadu, Palukuru and Machavarm villages are on river beds of Manneru and Paleru where the soil is alluvium (sandy loams to silty loams). Rice is grown during kharif followed by summer pulses in fallows in low lands. Cotton is grown in black soil with good ground water because of Manneru and Paleru streams. Redgram is grown in all types of soils as kharif crop. During rabi, sole crops like tobacco and chickpea are grown. Tobacco is grown under rainfed tanks and ponds in Mopadu and Kondamudusupalem, during dry periods. Spatial distribution of the analyzed water quality parameters with thematic maps using Arc GIS showed that pH varied from 7.4 to 9.2. EC varied from 0.24 to 4.25 dSm-1, but most of the area was in the range of 1.5-3.0 dSm-1. Higher concentrations of HCO3- content were recorded in the ground water of light textured red soil areas. Chloride concentration varied from 0.9 to 87.1 meq/l. CO3and HCO3- contents ranged from 0.0 to 4.4 and 1.8 to 23.8 meq/l, respectively. Anion concentration followed an order of chlorides > bicarbonates> carbonates. The carbonate/bicarbonate ratio in the sample varied from 0.02 to 0.53. With increase in carbonate and bicarbone concentration, chloride concentration decreased.Not Availabl

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Not AvailableNot AvailableDepartment of Agriculture, Cooperation & Farmers’ Welfare, Govt. of Indi

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Not AvailableThe objective of the study is to develop simple, inexpensive, and less hazardous extractant for simultaneous extraction of nicotine, reducing sugars, and chlorides in tobacco cured leaf. The currently used reference extractant for nicotine, reducing sugars, and chlorides comprises 20% aqueous methanol +5% acetic acid+2 cc charcoal in 15:4:1 ratio. As the methanol, a major component of this reference extractant, is hazardous and expensive, we proposed and evaluated a simple extractant involving 10%acetic acid for assaying nicotine, reducing sugars, and chlorides in comparison to reference extractant. The sample data (n = 30) sets of both the extractants [proposed (x) and reference (y)] were subjected to Passing &Bablok’s regression analyses. The regression models so obtained for reducing sugars (y = 0.594 + 1.021x), nicotine (y = 0.044 + 0.8877x), and chlorides (y = 0.057 + 1.131x) were validated by CUSUM test for linearity. The test indicated that there was no significant deviation from linearity for nicotine, reducing sugars, and chlorides. Spearman’s rank correlation coefficient (ρ) with P < .0001at 95% confidence interval also showed high correlation between the proposed and the reference extractants for Nicotine (0.993), reducing sugars (0.982), and chlorides (0.972). Analyses of the data sets by Youden plot method showed congregation of data points near to diagonal reference line and a few wild points. This type of data points distribution indicates the high degree of comparability between the proposed and the reference extractants for nicotine, reducing sugars, and chlorides in tobacco cured leaf. The estimated cost of extraction was less with the proposed extractant. It is suggested that the proposed extractant (10%acetic acid + 4 cc activated charcoal suspension) being simple and less expensive be used as an alternative to the hazardous methanol-based extractant.Not Availabl