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Abstract The exploration and development of the dual-provenance lower assemblage of the Yanchang Formation in the Jiyuan area has progressed rapidly. At the intersection of this bidirectional provenance system, a complex and variable spatial combination of sand bodies formed, resulting in significant structural heterogeneity in the development and distribution of reservoirs. Based on previous studies, this paper combines core data and logging data with a large number of analytical tests and production performance data to carry out research on the Chang 82–Chang 9 reservoir group in the lower assemblage of the Yanchang Formation in the Shijiawan-Buziwan area. Based on the analysis of sedimentary conditions, the sand body development pattern at the intersection of the bidirectional sedimentary system in the study area was analysed by stepwise dissection of the sand body architecture. After the types and characteristics of the 4th- to 5th-level architectural elements were determined, the spatial distribution of the combinations of these elements was assessed and combined with logging discriminant analysis and geometric shape prediction methods to identify a ‘prism’ architectural distribution pattern. The architectural elements are connected with the distribution of diagenetic facies, the spatial distribution patterns of different types of diagenetic facies under the constraints of the architecture are summarized by region, and the locations of potential favourable reservoir development are discussed. The results show that the degree of superposition and combination of the eight skeletal architectural elements in the target layers gradually deteriorate from the bottom to the top. In addition, the development scale and degree of architectural elements in the braided river delta system in the west are better than those in the meandering river delta system in the east. In the different sedimentary areas, the spatial combination styles of the architectural elements are quite different, and the combination of these elements gradually changes from a combination of braided channels (FA1) and abandoned channels (FA2) to a combination of underwater distributary channels (FA4). Matching of the distribution of diagenetic facies with the distribution of architectural elements reveals that the diagenetic facies dominated by intergranular pores and dissolution pores (associated with good reservoir physical properties) are usually found at the bottom or in the lower to middle parts of the skeletal architectural elements.

Abstract This study aimed to explore the risk factors of peripherally inserted central catheter (PICC)-related venous thromboembolism (CRT) in patients with hematological malignancies and the predictive ability of the thrombotic risk assessment models (RAMs). The clinical data of the 117 eligible patients with hematological neoplasms at Mianyang Central Hospital with PICC from May 2018 to May 2020 were analyzed in this retrospective study. Thrombosis risk scores were calculated in patients with image-confirmed PICC-related thromboembolism. CRT occurred in 19 cases. Compared to the CRT-free group, the CRT group was older and showed higher body mass index (BMI), leukocyte count level, and the prevalence of diabetes mellitus. Multivariable logistic regression analysis showed that BMI (P = 0.03) was a significant risk factor for CRT. The area under the receiver operating characteristic curve for the Caprini scale (P = 0.01) was higher than that of the modified Wells scale (P = 0.94), the revised Geneva scale (P = 0.83), Padua scale (P = 0.59), and Michigan scale (P = 0.80). The sensitivity and specificity for the Caprini scale, Padua scale, modified Wells scale, the revised Geneva scale, and Michigan risk score were 63.3%/73.7%, 100%/0.00%, 95.9%/5.3%, 31.6%/73.7%, and 1.0%/99.0%, respectively. Caprini RAM had a better predictive ability for CRT in patients with hematological malignancies. Michigan risk score may not be better than Caprini RAM in this population.

Abstract Fermentation process plays an important role in the biochemical properties and quality of cigar tobacco leaves (CTLs). In industry, exogenous additive (EA) was usually adopted for improving the quality of CTLs during fermentation. However, the mechanism of enhanced quality of CTLs fermented with EA was confused. Herein, the chemical compositions and microbial communities of CTLs during fermentation with EA were analyzed. The increased contents of total nitrogen and total sugar, as well as the improved consumption rate of reducing sugar in CTLs were found with the addition of EA. Besides, fermentation with EA reduced the content of total nonvolatile organic acid, especially unsaturated fatty acid. The contents of total and several representative aroma components were improved. Additionally, the increased abundance of Staphylococcus and decreased abundance of Aspergillus were detected. Combined with the changes of chemical compositions and microbial communities, it was confirmed that the carbohydrates and alcohols originated from EA promote the enrichment of Staphylococcus and accelerate biochemical reactions, such as Maillard reaction and esterification reaction, thus improving the contents and quality of aroma components in CTLs. This study demonstrated the mechanism of enhanced quality of CTLs fermented by EA, which provides more ideas for developing novel and efficient EAs.