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A heterogeneous platinum catalyst with tridentate pyridine Schiff base ligands supported on silica gel is reported. The catalyst was fully characterized via FTIR, solid-state 13C NMR spectroscopy, X-ray photoelectron spectroscopy (XPS), N2 adsorption/desorption analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The catalyst showed potential application in mediating hydrosilylation reactions between olefins and hydrosilanes, and it can be reused for at least five cycles. [ABSTRACT FROM AUTHOR]

Background: Studies on the relationship between thyroid function and non-alcoholic fatty liver disease (NAFLD) among euthyroid subjects have produced conflicting results.Objectives: The aim of this study was to investigate the association between thyroid function and the presence of NAFLD in a large-sample middle-aged euthyroid subjects.Methods: A total of 2576 euthyroid subjects who underwent health check-up were included. NAFLD was diagnosed by hepatic ultrasonography. Conventional risk factors for NAFLD were assessed as well as serum levels of TSH, FT3 and FT4.Results: Levels of FT3 were significantly higher in NAFLD group (5.12 ± 0.58 versus 4.84 ± 0.58 pmol/L, adjustedp = 0.000) than non-NAFLD group, while levels of TSH and FT4 were comparable between NAFLD and non-NAFLD groups (TSH: 2.13 ± 0.90 versus 2.20 ± 0.93 mIU/L, adjustedp = 0.190; FT4: 16.41 ± 2.04 versus 16.18 ± 2.06 pmol/L, adjustedp = 0.146, respectively). Levels of FT3 were positively correlated with components of metabolic syndrome. Multivariate logistic regression analysis revealed that high level of FT3 was an independent predictor for NAFLD (odds ratio: 1.253,p = 0.040). The relationship between FT4 and NAFLD in women was different according to menopausal status, with negative association in pre-menopausal women (OR: 0.777, 95% CI: 0.617–0.979,p = 0.032) and null association in post-menopausal women (OR: 1.037, 95% CI: 0.841–1.277,p = 0.736).Conclusions: Our findings suggested that high levels of FT3 were significantly associated with NAFLD among middle-aged euthyroid subjects independently of known metabolic risk factors. A negative correlation of serum FT4 level with NAFLD was only observed in pre-menopausal women. [ABSTRACT FROM AUTHOR]

Using potassium iodide as a catalyst andm-chloroperbenzoic acid as an oxidant, an efficient catalytic procedure has been developed for the azidoselenenylation of alkenes with sodium azide and diselenides, and a series of corresponding β-azidoselenides, most of which are new compounds, have been prepared in moderate to good yields under mild reaction conditions. This in situ generation of the electrophilic selenenylating reagents with addition to alkenes is a stereospecificantiaddition, which occurs with a Markovnikov orientation. [ABSTRACT FROM AUTHOR]

A convenient procedure is developed for the preparation ofN-sulfonylbenzotriazoles from sodium sulfinates, benzotriazoles, and sodium bromide in the present ofm-chloroperbenzoic acid as oxidant. This radical sulfonylation proceeds efficiently at room temperature under neutral conditions, affording the correspondingN-sulfonylbenzotriazoles in moderate to good yields in a short time. [ABSTRACT FROM AUTHOR]

In light of the technological advancement and green growth in G7 economies, this research investigates the trends in sustainable development goals (SDGs) as reflected through social and environmental dimensions. Data were collected from 2000 to 2019 with yearly observation for advanced panel estimations.The preliminary finding raises the issues of cross-sectional dependency and slope heterogeneity; thus, we have applied the cross-sectional autoregressive distributed lag(CS-ARDL) model.The long-run findings confirm that technological innovations and green growth encourage environmental sustainability. Moreover, economic growth, green technological innovations, and government effectiveness have significantly promoted social development through higher employment opportunities. Similar results are also observed in the short run; however, the influence is more substantial in the long run. These findings imply that green growth, eco-innovations, and institutional governance are core drivers of SDGs in the long run. [ABSTRACT FROM AUTHOR]

The flow over a stationary cylinder is destabilized mainly in the separated shear layer (SSL) and wake regions and transverse shedding forms downstream of the cylinder. It has been revealed that aiding/opposing buoyancy or diverging/converging channel could stabilize/destabilize the separated and wake flows, while their joint effect has not been investigated. In this numerical investigation, the low-Re buoyancy-driven flow over a circular cylinder placed in a channel consists of diverging or converging walls is studied. We aim to reveal the effects of two parameters, i.e. Richardson number Ri representing buoyancy and channel angle α, on the flow dynamics and heat transfer. The cases of aiding (Ri > 0) and opposing (Ri < 0) buoyancy, and diverging (α > 0) and converging (α < 0) channels are considered in this work. The effects of Ri and α are presented in terms of the instantaneous flow field, global characteristic quantities, heat transfer between the fluid and cylinder surface, separation and shearing of wake flow, and temperature variations of the channel walls. We found that the flow transits to steady subjected to aiding buoyancy at a lower value of Ri where the fluctuations of force and heat transfer rate reduces to zero; however, the mean drag and Nusselt number do not exhibit monotonic variations with Ri. The convection heat transfer is prone to be notably affected by Ri rather than α on the leeward side of the cylinder, and its fluctuation is significant in the separation zone downstream of the separation point. Depending on the value of Ri, the steady and unsteady wake flow present different velocity profile as well as the shearing; the deficit wake flow recovers more rapidly for the steady flow cases. [ABSTRACT FROM AUTHOR]

This article uses the lens of small state theory to assess New Zealand's role in the Five Eyes Alliance and Wellington's implementation of intelligence reforms in the last seven years that are intended to help the country deal with a transformed security environment. In this context, New Zealand decision-makers have become increasingly concerned about growing Chinese influence in the South Pacific region and in New Zealand itself. It is clear that the New Zealand's response to these developments resembles that of a minor power rather than a classical small state. [ABSTRACT FROM AUTHOR]