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BACKGROUND: Cardiac dysfunction accompanies acute ischemic stroke and affects the effective implementation of early rehabilitation interventions. There is a lack of reference hemodynamic data on cardiac function in the subacute phase of ischemic stroke. OBJECTIVE: In this study, we aimed to identify appropriate cardiac parameters for exercise training utilizing a pilot study. METHODS: We used a transthoracic electrical bioimpedance non-invasive cardiac output measurement (NICOM) device to monitor cardiac function in real time for two groups [i.e., subacute ischemic stroke inpatients group (n = 10) and healthy control group (n = 11)] using a cycling exercise experiment. The parameters of both groups were compared to highlight the cardiac dysfunction in the subacute phase in patients with ischemic stroke. RESULTS: We considered stroke volume index (SVI) and systemic vascular resistance index (SVRi) as the primary outcomes, and there was significant intragroup difference (stroke group: P < 0.001; control group: P < 0.001, using one-way ANOVA) and significant intergroup difference at each individual time segment (P < 0.01, using independent t -test). Among the secondary outcomes, i.e., cardiac index (CI), ejection fraction (EF), end-diastolic volume (EDV), and cardiac contraction index (CTI), we found significant intergroup differences in CI, EF, and CTI scores (P < 0.01, using independent t -test). Significant interaction with respect to time and group were seen only in the SVRi and CI scores (P < 0.01, using two-way ANOVA). There was no significant inter- or intra-group differences in EDV scores. CONCLUSION: SVRI, SVI, and CI values highlight cardiac dysfunction in stroke patients the most. At the same time, these parameters suggest that cardiac dysfunction in stroke patients may be closely related to the increased peripheral vascular resistance caused by infarction and the limitation of myocardial systolic function. [ABSTRACT FROM AUTHOR]

Presents a study which examined the effects of land use and its patterns on soil moisture and nutrients in the hilly area of Loess Plateau in China. Description of the study area; Comparisons of soil moisture among land uses for wet and dry years; Effects of landscape position on soil nutrients.

Surface ozone (O 3 ) has become a critical pollutant impeding air quality improvement in many Chinese megacities. Chengdu is a megacity located in Sichuan Basin in southwest China, where O 3 pollution occurs frequently in both spring and summer. In order to understand the elevated O 3 during spring in Chengdu, we conducted sampling campaign at three sites during O 3 pollution episodes in April. Volatile organic compounds (VOCs) compositions at each site were similar, and oxygenated VOCs (OVOCs) concentrations accounted for the highest proportion (35%-45%), followed by alkanes, alkens (including acetylene), halohydrocarbons, and aromatics. The sensitivity of O 3 to its precursors was analyzed using an observation based box model. The relative incremental reactivity of OVOCs was larger than other precursors, suggesting that they also played the dominant role in O 3 formation. Furthermore, the positive matrix factorization model was used to identify the dominant emission sources and to evaluate their contribution to VOCs in the city. The main sources of VOCs in spring were from combustion (27.75%), industrial manufacturing (24.17%), vehicle exhaust (20.35%), and solvent utilization (18.35%). Discussions on VOCs and NO x reduction schemes suggested that Chengdu was typical in the VOC-limited regime, and VOC emission reduction would help to prevent and control O 3 . The analysis of emission reduction scenarios based on VOCs sources showed that the emission reduction ratio of VOCs to NO 2 needs to reach more than 3 in order to achieve O 3 prevention. Emission reduction from vehicular exhaust source and solvent utilization source may be more effective., (Copyright © 2021. Published by Elsevier B.V.)