Publications by authors named "Jinchao Yang"

3 Publications

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Hydrochemical characterization and quality assessment of groundwater in the hilly area of the Taihang Mountains in Henan Province, China.

Environ Sci Pollut Res Int 2021 Apr 10. Epub 2021 Apr 10.

Henan Institute of Geological Environment Monitoring, Zhengzhou, 450016, China.

This study evaluated the quality of groundwater and its suitability for drinking and irrigation in the hilly area of the Taihang Mountains in Henan Province, China. Groundwater samples were collected from 43 unconfined and 20 confined wells and analyzed. The pollution index of groundwater (PIG) was estimated based on the physicochemical parameters, and seven indices, including the sodium adsorption ratio (SAR), sodium percentage (%Na), residual sodium carbonate (RSC), permeability index (PI), magnesium ratio (MR), Kelley's ratio (KR), and corrosivity ratio (CR), were calculated to qualify the groundwater within the research area for irrigation activities. Multivariate statistical techniques were performed to better understand the hydrochemical processes. Chemical analysis showed that the dominant cation and anion were Ca and HCO, respectively, and the principal hydrochemical facies was Ca-Mg-HCO. In terms of pH, total dissolved solids, Na, Cl, F, and SO, most samples were well within the limits prescribed by Chinese standards for drinking water quality, but more than half of the unconfined samples exceeded the specified limits for total hardness and nitrate. The PIG values suggested the pollution level was insignificant for all confined water samples and 72.09% of unconfined water samples, but the PIG distribution map showed that the water in the south central part of the study area had low to moderate pollution. According to the computed values of SAR, %Na, RSC, PI, KR, and MR and the results of a salinity diagram, the results further indicated that most of the studied samples were appropriate for irrigation usage. Only the CR values rendered 41.86% of the unconfined samples and 20% of the confined samples unfit for irrigation. Hence, proper measures are needed to resolve the corrosivity problem. Factor analysis resulted in the extraction of 3 factors that explained 81% of the data variability, and the extracted factors pointed towards geogenic factors governing the groundwater quality.
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April 2021

The effectiveness of low intensity exercise and blood flow restriction without exercise on exercise induced muscle damage: A systematic review.

Phys Ther Sport 2020 Nov 25;46:77-88. Epub 2020 Aug 25.

Rangos School of Health Sciences, Duquesne University, Pittsburgh, PA, USA. Electronic address:

Objective: To investigate the evidence and provide clinical recommendations for low intensity exercises(LIE) and blood flow restriction(BFR) without exercise on reducing the effects of exercise induced muscle damage(EIMD).

Method: PubMed, Embase, Web of science, and PEDro(Physiotherapy Evidence Database) were searched up to December 2019 for studies that included LIE or BFR without exercise and their effect on EIMD.

Results: Out of 3192 studies, 23 were included with 17 on LIE and 6 on BFR without exercise. 11 studies demonstrated positive effects for LIE on EIMD, with two level 2 and nine level 3 studies. Two level 2 and two level 3 studies found benefits for BFR without exercise on reducing the negative effects of EIMD, while two level 2 studies found did not find benefits for BFR without exercise.

Conclusion: Moderate to low levels of evidence supported LIE, particularly in the form of protective low load eccentric exercise, in reducing the negative effects of EIMD. Conflicting moderate to low levels of evidence was found regarding BFR without exercise. There does seem to be potential benefit for BFR without exercise in untrained individuals. Clinicians can provide clinical recommendations as LIE and BFR without exercise reducing EIMD.
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November 2020

Enantioselective bifunctional iminophosphorane catalyzed sulfa-Michael addition of alkyl thiols to unactivated β-substituted-α,β-unsaturated esters.

Chem Sci 2017 Jan 14;8(1):606-610. Epub 2016 Sep 14.

Department of Chemistry , Chemistry Research Laboratory , University of Oxford , 12 Mansfield Road , Oxford , UK . Email:

The highly enantioselective sulfa-Michael addition of alkyl thiols to unactivated β-substituted-α,β-unsaturated esters catalyzed by a bifunctional iminophosphorane (BIMP) organocatalyst is described. The low acidity of the alkyl thiol pro-nucleophiles is overcome by the high Brønsted basicity of the catalyst and the chiral scaffold/thiourea hydrogen-bond donor moiety provides the required enantiofacial discrimination in the addition step. The reaction is broad in scope with respect to the alkyl thiol and β-substituent of the α,β-unsaturated ester, affords sulfa-Michael adducts in excellent yields (up to >99%) and enantioselectivity (up to 97 : 3 er) and can operate down to 1 mol% catalyst loading.
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January 2017