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The structural, mechanical and thermal properties of perovskite BaZrS3 have been investigated in terms of first-principles plane-wave pseudopotential method. Four structures such as GdFeO3-type, BaNiO3-type, NH4CdCl3-type and CaTiO3-type structures are considered. The results show that the calculated lattice structural results of perovskite BaZrS3 with the GdFeO3-type phase are in good agreement with the available experimental data. It is predicted that those structures are thermodynamically stable. The structural stability order of the four phases is GdFeO3-type > NH4CdCl3-type > CaTiO3-type > BaNiO3-type from the calculated formation energies. The elastic constants of the four structures prove that GdFeO3-type, NH4CdCl3-type and CaTiO3-type structures are mechanically stable while the BaNiO3-type structure is mechanically unstable. The mechanical properties of perovskite BaZrS3 such as the bulk modulus, shear modulus, Young’s modulus and elastic anisotropy were calculated from the obtained elastic constants. The analysis of B/G ratio confirms that perovskite BaZrS3 is ductile materials. In particular, we firstly report the theoretical prediction of the thermal properties including Debye temperature and melting temperature of perovskite BaZrS3.

A process and equipment for preparing activated carbon from straw and its application in treating uranium wastewater are proposed. The ZnCl2-microwave carbonization method is adopted, which flexibly applies the wave absorbing ability of zinc element and greatly reduces the carbonization time. At the same time, the dehydrogenation of ZnCl2 limits the formation of coal tar and improves the carbon formation rate. Through citric acid modification, a functional group with specific adsorbability to uranyl ions is formed, which can produce high-efficiency complexation effect with uranyl ions and improve the adsorption capacity of uranyl ions. When the wastewater is mixed with other heavy metal elements, uranyl ions occupy the main adsorption sites, which can still maintain excellent targeted adsorption effect and can be targeted to treat uranyl ions in radioactive uranium wastewater. The key equipment in the process consists of cleaning and impurity removal components, raw material crushing components and carbonization components. The whole production process is completed in the same equipment. The optimum adsorption capacity (Ac) of 4.98 mg/g and uranium adsorption rate (Ar) of 99% were obtained by using soybean straw as raw material under the preparation conditions of 20% ZnCl2 solution and 15% citric acid solution.

To identify the effect of internal carotid artery (ICA) stenosis, blood pressure (BP), glycated hemoglobin (HbA1c), and hemoglobin level on blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) signals in stroke patients.A total of 18 stroke patients with acute cerebral infarction (13 males and 5 females) and 13 age-matched healthy controls (5 males and 8 females) were recruited. Among 18 stroke patients, 8 had significant ICA stenosis (50%) and 10 had nonsignificant ICA stenosis (50%). During handgrip task, stroke patients and normal controls were allowed to use their hands coincided with infarction and right hands, respectively.The mean BOLD signals in patients with significant ICA stenosis were significantly less than that in patients with nonsignificant ICA stenosis. Mean arterial pressure (MAP) was significantly correlated with activated voxels of Brodmann area 4 (P0.01) and total activated voxels (P = 0.007), whereas hemoglobin and HbA1c showed no significant correlation with activated voxels of Brodmann area 4 or total activated voxels (P0.05).It is suggested that both ICA stenosis and arterial BP could influence BOLD signal, while HbA1c and hemoglobin level had no effect on BOLD signal.

Stroke in young adults may have early impact on quality of life in survivors. Uncontrolled stroke risk factors, lack of treatment facilities and a dense population has made its special significance in South Asia. The main aim of this study is to evaluate incidence, risk factors, etiology and clinical characteristics of young ischemic stroke in South Asia. Incidence of young stroke is more common in South Asian countries than developed western countries and has higher prevalence in rural areas. Traditional risk factors, such as hypertension, smoking, hyperlipidemia and diabetes are associated with majority of cases. Cardioembolism and undetermined etiology contribute to a large proportion of stroke etiology. Appropriate stepwise investigations are suggested to diagnose stroke of other determined etiology. Regular intake of drugs to control risk factors, cessation of smoking, and promote physical activity is suggested to reduce the burden of young stroke. Journal of Advances in Internal Medicine 2013;02(01):27-33 DOI: http://dx.doi.org/10.3126/jaim.v2i1.7636