The study on spatial distribution of water ecological environment carrying capacity during extreme drought conditions.

Due to global warming and the disturbance of the interannual variability of precipitation, the frequency of extreme drought events has increased. The impact of global climate change on water resources is becoming increasingly apparent, then it is particularly necessary to explore the carrying capacity of water ecological environment under extreme drought conditions, which can guarantee the ecological water security in river basins. This study takes the Guanzhong area of the Wei River Basin as an example, calculating the water environment carrying capacity of 40 areas in the Weihe Guanzhong area in different levels of years under extreme drought conditions by comprehensive evaluation model of carrying capacity and using geographic information system GIS to display the spatial distribution of water environment carrying capacity in 40 regions. According to the results of the spatial distribution of water environmental bearing capacity, four different schemes are designed to improve the bearing capacity. The first plan reduces the industrial water consumption and irrigation quota by 5%, the second plan increases the industrial water and sewage treatment rate on this basis. the third plan further improves the development and utilization rate of surface and groundwater, and the fourth plan, on the basis of the first three plans, supplies 600 million cubic meters of industrial and agricultural water to Guanzhong region. Through comparative analysis, without taking any measures, under the extreme drought conditions, the water environment carrying capacity of the 40 areas in Guanzhong is all in an unbearable state. Overall, plan 4 has the most significant improvement in the water environment-carrying capacity, especially the Dong zhuang Reservoir of the Jing River which has played a very important role in enhancing the water ecological environment carrying capacity of the downstream water of the Wei River.

Trityl Cation-Catalyzed Hosomi-Sakurai Reaction of Allylsilane with ß,γ-Unsaturated α-Ketoester to Form γ,γ-Disubstituted α-Ketoesters.

(Ph3C)[BPh(F)4]-catalyzed Hosomi-Sakurai allylation of allylsilanes with ß,γ-unsaturated α-ketoesters has been developed to give γ,γ-disubstituted α-ketoesters in high yields with excellent chemoselectivity. Preliminary mechanistic studies suggest that trityl cation dominates the catalysis, while the silyl cation plays a minor role.

Early expressed circulating long noncoding RNA CHAST is associated with cardiac contractile function in patients with acute myocardial infarction.

BACKGROUND: The mortality rate during the acute myocardial infarction (AMI) phase has substantially decreased, but post-AMI cardiac remodeling remains an important factor affecting patient prognosis. Several circulating long noncoding RNAs (lncRNAs) are reportedly involved in the chronic pathological process of cardiac function and remodeling in cardiovascular diseases. However, the potential roles of these circulating lncRNAs as biomarkers of cardiac function and remodeling during early-stage AMI remain unclear. METHODS: Fifty-three patients with AMI and 90 controls without AMI were consecutively enrolled in this study. Clinical parameters and blood samples at different time points (i.e., 24 h and 3 days) were collected. RESULTS: Compared with the controls, the circulating levels of cardiac hypertrophy-associated transcript (CHAST) significantly increased in AMI patients, and the CHAST levels obviously decreased at 3 days. In AMI patients, the expression levels of CHAST at 24 h were positively associated with cardiac contractile function and measured as left ventricular ejection fraction and left ventricular short-axis shortening rate (all P < 0.050). Multivariate regression analysis indicated that the expression level of CHAST at 24 h was an independent predictor of cardiac contractile function (standardized ß = 0.319, P =0.034). When grouped according to the quartile values of the CHAST in the AMI population, patients with the highest quartiles of CHAST expression level showed better cardiac contractile function than all the other quartiles (all P < 0.050). CONCLUSION: CHAST was an independent predictor of cardiac contractile function at early-stage AMI and may serve as a candidate biomarker for cardiac remodeling.

Me3 Si-SiMe2 [oCON(iPr)2 -C6 H4 ]: An Unsymmetrical Disilane Reagent for Regio- and Stereoselective Bis-Silylation of Alkynes.

The air-stable unsymmetrical disilane Me3 Si-SiMe2 [oCON(iPr)2 C6 H4 ] has been developed for bis-silylation of alkynes. This reagent tolerates a range of functional groups, providing Z-vinyl disilanes in high yields. It is proposed that the phenyl-ring-tethered amide group directs oxidative addition of Pd0 into the Si-Si bond, which might facilitate formation of a six-membered Pd cycle, generating products with good to excellent regioselectivity.