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This study delves into the micro-occurrence states and enrichment mechanisms of residual oil, pivotal for advancing the production from tight sandstone reservoirs, particularly from the Chang 8 Member of the Upper Triassic Yanchang Formation, Ordos Basin. Through an analysis of 23 core samples, employing high-pressure mercury injection, field emission scanning electron microscopy, thin section, and X-ray diffraction techniques, distinct reservoir types were categorized. The utilization of environmental scanning electron microscope, multi-solvent continuous extraction, and an oil components separation system facilitated an intricate analysis of residual oil micro-occurrence states and their subsequent effects on porosity and permeability reduction across varying reservoir types. The findings accentuate the integral role of reservoir type in determining residual oil distribution within tight sandstone reservoirs. Favorable pore throat sorting and connectivity in specified reservoir types are identified as conducive to residual oil enrichment with a higher concentration of light components. In contrast, elevated carbonatite and clay content in other reservoir types leads to adsorption of heavy components, disrupting pore throat connectivity, and impeding crude oil filling. The varied interactions between oil and rock, oil–oil, and pore throat sealing significantly impact the distribution of oil components of residual oil, culminating in a notable reduction of porosity and permeability by 2.63% and 0.197 mD, with corresponding reduction rates of 27.19% and 46.69%, respectively. The insights derived from this study furnish a theoretical foundation for augmenting tight oil recovery and comprehending the enrichment mechanism of residual oil driven by the heterogeneity of tight sandstone reservoirs. [ABSTRACT FROM AUTHOR]

Abstract: This research studies the low carbon transition of the electric power sector in China using a multi-level perspective (MLP) of niches, socio-technical regime, and landscape, as well as literature on innovation systems. Three lines of thought on transition process are integrated in the paper to probe the possible transition pathways in China. A MLP analysis is presented to understand the current niches, regime, and landscape of China’s power sector. A brief analysis on the future macroscopic socio-economic transition in the process of industrialization, urbanization, and modernization of Chinese society and its implication on power landscape are depicted to prove the urgency and magnitude of transition in China and why systematic transition management is needed. Five transition pathways, namely reproduction, transformation, substitution, reconfiguration, de-alignment/re-alignment, and reconfiguration, with their possible technology options are presented. The paper goes further to propose an interactive framework for managing the transition to a low carbon energy system in China. Representative technology options are appraised by employing innovation theory to indicate the logic of policymaking within the framework. Institutional gaps in realizing the transition are also addressed. The work presented in the paper will be useful in informing policy-makers and other stakeholders and may provide references for power sector transition management in other countries. [Copyright &y& Elsevier]

The in-utero environmental exposure to fine particulate matter (PM 2.5 ) might lead to adverse birth outcomes, such as low birth weight (LBW) and preterm birth (PTB), thereby increasing susceptibility to diseases in later life. However, no studies have examined the underlying mechanism through cross-omics of lipidome and adipokines profiling, as well as the possible effect modification by maternal hyperlipidemia. In total, 203 mother-newborn pairs were recruited in the birth cohort study ongoing since February 2017 in Beijing, China. Individual-level of PM 2.5 exposure was estimated using a satellite data based random forest model. Cord blood lipidome and adipokines were assessed through the lipidomic approaches and antibody-based array. Multivariable logistic/linear regression models and moderation analysis were employed in this study. We observed a significantly increased risk of PTB associated with PM 2.5 exposure during the second trimester, especially in pregnant women with pre-existing hyperlipidemia. 9 lipid classes and 21 adipokines were associated with PM 2.5 exposure independently or significantly influenced by the interaction of maternal PM 2.5 exposure and hyperlipidemia. In addition, 4 adipokines (ANGPTL4, IGFBP-2, IL-12p40, and TNF-RII) and 3 lipid classes [phosphatidylcholines (PCs), phosphatidylinositols (PIs), and triglycerides (TGs)] were related to the increased risk of PTB, indicating that inflammation, IGF/IGFBP axis, and lipolysis induced lipid homeostasis disorder of PCs, TGs, and PIs might be the possible mediators for the PM 2.5 -induced adverse birth outcomes. Our results substantiated the need for reducing exposure in susceptible populations., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:, (Copyright © 2021 Elsevier B.V. All rights reserved.)

The HOXA1 gene plays a fundamental role in embryonic morphogenesis. Recent studies in humans and mice have indicated that HOXA1 plays a previously unrecognized role in cardiovascular system development. Congenital heart disease (CHD), particularly ventricular septal defect (VSD), might be a clinically isolated manifestation of HOXA1 mutations. The purpose of the present study was to identify potential pathological mutations in the HOXA1 gene in Chinese children with VSD and to gain insight into the etiology of CHD. A total of 340 nonsyndromic VSD patients and 200 normal subjects were sampled. Two exons and the nearby introns of the human HOXA1 gene were amplified using polymerase chain reaction (PCR). The PCR products were purified and directly sequenced. However, no nonsynonymous mutations in the coding regions of the HOXA1 gene were observed: Only two novel synonymous mutations (c.C210T p.His70His, and c.T861A p.Arg287Arg) were found in two patients. Two previously reported single and multiple histidine-deletion variants were identified in both normal and VSD patients. To our knowledge, this is the first study to investigate the role of the HOXA1 gene in CHD. Although our results did not show any pathogenic HOXA1 mutation, our results suggest that VSD might not be a clinically isolated manifestation of HOXA1 mutations.