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Objective To explore the related factors of weekly blood pressure variability (BPV) on maintenance peritoneal dialysis (MPD).Methods A total of 142 patients on MPD for at least 3 months were recruited. Blood pressure was assessed weekly by variation coefficient (CV) of systolic blood pressure in morning. The relevant clinical data was collected. The association of BPV and predictors were estimated by a mixed-effect linear model. Results Longer dialysis vintage was associated with elevated weekly BPV (P0.05). Conclusions Weekly BPV may be affected by dialysis vintage, hemoglobin concentration, daily fluid removal and dosing of calcium antagonists.

The preparation of high-value-added platform compounds from biomass materials provides an important method for solving fossil energy shortages. Known as the “sleeping giant”, 5-HMF is one of the most important biomass platform compounds with promising applications. At present, raw materials for the preparation of 5-HMF mainly comprise sugar compounds and non-food biomass. The current systems for preparing 5-HMF are disadvantaged by poor selectivity and a low conversion rate. This paper focuses on the catalytic mechanisms and catalytic systems for the synthesis of 5-HMF from different biomass feedstocks and reviews a series of existing techniques for the preparation of 5-HMF. Catalytic systems for the synthesis of 5-HMF from different feedstocks are also discussed in depth, providing theoretical support for its subsequent in-depth study. The development of efficient catalysts and catalytic systems for the conversion of polysaccharide raw materials into 5-HMF is anticipated.

The spatial and temporal evolution of the sandbody architecture of shallow-water deltas in open lacustrine basins is controlled by the classification of allocyclicity and autocyclicity. On the southwestern margin of the Ordos Basin, a braided river system deposited a shallow-water delta in the Late Triassic Period. Based on the principle of sequence stratigraphy and the hierarchical analysis of reservoir architecture, the spatial and temporal evolution of individual sandbodies in the Chang 81 member of the Yanchang Formation in the Zhenbei Oilfield is interpreted by utilizing data from cores, wells and outcrops. The research ideas are as follows: large deposition scale architectural elements (first- to third-order cycles, as defined by Miall) of different sequence levels are affected by allocyclicity associated with changes in tectonic activity, provenance, and sea level, and small deposition scale architectural elements (fourth- to fifth-order cycles, as defined by Miall) of different sedimentary facies mainly consist of individual sandbodies that are affected by autocyclicity associated with lake-level changes caused by various river processes. Based on previous studies, the results are as follows. The sedimentary characteristics of shallow-water deltas have been verified by core and outcrop data. In addition, three ultrashort-term cycles are identified on the basis of boundary sequences and lithofacies’ sequences in the outcrop section of the Rui River, and three sedimentary evolution stages of the delta front are defined. Finally, according to well data, five types of architectural elements at the level of single sandbodies are identified. The vertical superimposition and lateral contact relationships of different architectural elements indicate that during the three sedimentary evolution stages, the hydrodynamics weakened, strengthened slightly, and finally weakened substantially. Among the 20 kinds of architectural element spatial combination patterns formed by single sandbodies, primary and secondary sandbodies have great potential for hosting remaining oil. In the process of architectural spatiotemporal evolution, the geometry and connectivity of the underwater distributary channel gradually weakened, and the spatial relationship between the underwater distributary channel and other architectural elements increased. This article proposes a new method for researching shallow-water deltas and has some guiding significance for exploiting the remaining oil in oil fields.

Despite the continuous improvement in the research and development of concrete precast composite slab technology, problems like easy cracks and excessive weight at the joints remain. In this study, high-titanium heavy slag was mixed with different kinds of ceramsite to prepare ceramsite lightweight high-titanium heavy slag concrete. The joint of the composite slab was optimized to develop a novel ceramsite lightweight high-titanium heavy slag concrete precast composite slab, hereinafter referred to as "CLHCPCS". Two CLHCPCS and one ordinary concrete composite slab were prepared. This study analyzed the effects of new materials and improved joints on the flexural capacity and crack resistance of CLHCPCS. It concluded that the density of high-titanium heavy slag concrete with shale ceramsite decreased by 12.0%, and the density of high-titanium heavy slag concrete with fly ash ceramsite decreased by 10.6%. At a 30% dosage of fly ash ceramsite, the compressive strength and splitting tensile strength of concrete reached the maximum. At a 20% dosage of shale ceramsite, the mechanical properties were optimal. Finally, fly ash ceramsite was selected as part coarse aggregate of CLHCPCS. CLHCPCS 1 and 2 demonstrated superior ultimate bearing capacity and crack resistance than ordinary concrete composite slab DBS1, with its ultimate bending capacity test value higher than the average value of ordinary concrete composite slab. ANSYS established the joint model of CLHCPCS for a bending simulation test. The stress and strain distribution of the model and the ultimate bending capacity under the plastic line method were obtained, consistent with theory and experimental analysis results. [ABSTRACT FROM AUTHOR]