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The extremely thick dark mudstone of the Permian Linxi Formation in the Kundu-Taohaiyingzi area of northeastern China is a promising potential area for shale gas prospecting in the periphery of the Songliao Basin. This study involved a geological field survey, outcrop sample collection, and comprehensive geochemical analysis to conduct an in-depth analysis of the organic matter enrichment and hydrocarbon generation potential of the dark mudstone of the target zone, using organic petrology and organic geochemistry. The results show that the thermal maturity of the dark mudstone of the Linxi Formation is in the mature to high-mature stage. The organic matter is dominated by type II kerogen and supplemented by type III kerogen, and the average total organic carbon content is 0.76%, classifying it as a medium-good source rock. The main peak of carbon numbers is primarily distributed between nC17 and nC19, with a smaller amount at nC21. The distribution of n-alkanes follows a pre-peak pattern characterized by medium and low carbon numbers, suggesting that the organic matter originates from aquatic plants, bacteria, and algae. Combined with the fact that the ratios of pristine and phytane (Pr/Ph) are mainly distributed in the range of 0.99â1.33, the sedimentary environment is a weakly reduced to weakly oxidized lacustrine bay. The systematic analysis of the source rocks of the Upper Permian Linxi Formation in the Kundu-Taohaiyingzi area indicates favorable prospects for shale gas exploration. Utilizing a comprehensive superposition method of geological information, this article identified the Yamen GachaâSaihan Tala area as a potential area for shale gas exploration.

To study the impact of faults on the enrichment and mobility of shale oil in the Gulong area, representative rock samples were selected in this paper. Based on geochemical data and chemical kinetics methods, coupled with shale oil enrichment and mobility analysis techniques, the shale oil generation quantity and in situ oil content were evaluated from the perspectives of shale oil generation and micro migration, and the mobility of shale oil was revealed. At the same time, the hydrocarbon expulsion efficiency (HEE) of shale was qualitatively and quantitatively characterized, combined with the development of faults. The research results indicate that the study area mainly develops organic-rich felsic (ORF)/organic-containing felsic (OCF) shale, their proportion in both wells exceeds 65%, and the resource amount is the largest in this type of lithofacies. The development of a fault controls the enrichment of shale oil, and the in situ oil content and oil saturation index (OSI) of the shale in well Y58, which is close to the fault, are significantly worse than those in well S2. Well Y58 has 9.52 mg/g and 424.83 mg/g TOC respectively, while well S2 has 11.34 mg/g and 488.73 mg/g TOC respectively. The fault enhanced the migration of shale oil, increasing the efficiency of oil expulsion. As a result, the components with weak polarity or small molecules, such as saturated hydrocarbons and low carbon number n-alkanes, are prone to migration, reducing the mobility of shale oil.

In order to study the influencing factors for the enrichment of organic matter in Mesozoic and Cenozoic shale in lacustrine basins, the Pearson analyses of algal assemblages, physical and chemical properties of water body, sedimentary grain size, magnetic susceptibility and chromaticity were carried out from the aspect of modern lacustrine deposition. The coupled relationship between modern algal assemblages and water body, surface sediments in the Zhongnei Lake, which is a semi-enclosed shallow lake in the Songnen Plain, showed that topography and wind field affected the enrichment of organic matter in semi-enclosed brackish lakes with acidic and mixed water bodies. In different sites of the Zhongnei Lake, the abundance of cyanobacteria, green algae and diatoms are affected by water temperature and has a certain relationship with the degree of sediment sorting. Water temperature and sediment sorting are significantly controlled by the interference of local wind field.

The Cellulose synthase (CesA) and Cellulose synthase-like (Csl) gene superfamilies encode key enzymes involved in the synthesis of cellulose and hemicellulose, which are major components of plant cell walls, and play important roles in the regulation of fruit ripening. However, genome-wide identification and functional analysis of the CesA and Csl gene families in strawberry remain limited. In this study, eight CesA genes and 25 Csl genes were identified in the genome of diploid woodland strawberry (Fragaria vesca). The protein structures, evolutionary relationships, and cis-acting elements of the promoter for each gene were investigated. Transcriptome analysis and quantitative real-time PCR (qRT-PCR) results showed that the transcript levels of many FveCesA and FveCsl genes were significantly decreased during fruit ripening. Moreover, based on the transcriptome analysis, we found that the expression levels of many FveCesA/Csl genes were changed after nordihydroguaiaretic acid (NDGA) treatment. Transient overexpression of FveCesA4 in immature strawberry fruit increased fruit firmness and reduced fresh fruit weight, thereby delaying ripening. In contrast, transient expression of FveCesA4-RNAi resulted in the opposite phenotypes. These findings provide fundamental information on strawberry CesA and Csl genes and may contribute to the elucidation of the molecular mechanism by which FveCesA/Csl-mediated cell wall synthesis regulates fruit ripening. In addition, these results may be useful in strawberry breeding programs focused on the development of new cultivars with increased fruit shelf-life.

IntroductionHuman brucellosis is a severe public concern in Shaanxi Province, China, and investigating the epidemiological relationship and transmission pattern of B. melitensis is necessary to devise control strategies.MethodsIn this study, a conventional bio-typing approach and whole genome sequencing of single-nucleotide polymorphisms (SNPs) were employed to identify 189 strains.ResultsBased on the conventional bio-typing, 189 Brucella strains were identified as B. melitensis, of which 14 were in bv. 1, 145 were in bv. 3, and 30 were variant, and the Brucella strains were distributed in all ten cities in Shaanxi Province. SNP analysis was used to identify genetic variation in 189 B. melitensis genomes, and maximum-likelihood was used to generate a phylogeny that identified two clades (A and B) and 19 sequence types (STs). The two clades were highly diverse and exclusively of Eastern Mediterranean origin. Clade B contained 18 STs (2-19), with most isolates originating from a broad swath, implying that multiple B. melitensis lineages circulated in Shaanxi. The 19 STs were composed of 3 to 46 strains isolated from different counties and years, suggesting that multiple cross-county brucellosis outbreak events are driven by multiple B. melitensis lineages. Global phylogenetic analysis revealed that clade A was close to GTIIb, and clade B was placed in the GTIIh lineage, expanding the known diversity of B. melitensis from China.ConclusionThe human brucellosis epidemic in Shaanxi is driven by multiple indigenous circulating B. melitensis lineages, the knowledge of which will contribute to devising a control strategy and providing the foundation for a comprehensive regional phylogeny of this important zoonotic pathogen.

With the booming of worldwide agriculture intensification, brucellosis, one of the most neglected zoonotic diseases, has become an increasing challenge for global public health. Although the transmission patterns of human brucellosis (HB) have been studied in many regions, the dynamic transfer processes of risk and its driving factors remain poorly understood, especially in the context of agricultural intensification. This study attempted to explore the risk transfer of HB between the exact epidemic areas and the neighboring or distant low-risk areas to explain the impact of livestock agriculture intensification and foodborne infections on the transmission of HB in Shaanxi Province as a case study. We adopted multiple approaches, including test-based methods, model-based methods, and a geographical detector to detect the spatial-temporal dynamic changes of high-risk epidemic areas of HB at the county scale. We also quantitatively estimated how the related factors drove the risk transfer of the disease. Results confirmed the risk transfer pattern of HB with an expansion from north to south in Shaanxi Province and identified two primary transfer routes. In particular, in the traditional epidemic areas of the Shaanbei plateau, the farm agglomeration effect can significantly increase the risk of HB. Meanwhile, retail outlets for milk and dairy products were partially responsible for the foodborne infections of HB in the emerging epidemic areas of Xi'an. This study not only contributed helpful insights to support HB control and prevention in the rapid transition of livestock agriculture but also provided possible directions for further research on foodborne HB infections in urbanized areas.