The J -integral fracture toughness of PP/CaCO 3 composites

The J -integral method was introduced to investigate the fracture process of PP/CaCO 3 composites. The results showed that the resistance of PP/CaCO 3 composites to crack initiation and propagation was greatly improved with the addition of CaCO 3 filler. Large scale plasticity was caused in PP/CaCO 3 composites, from which a large amount of energy was absorbed by the PP matrix. The reason for the increase in the fracture toughness of PP/CaCO 3 composites was attributed to the partial micro-drawing ahead of the crack tip in the PP matrix, which was formed by the stress concentration caused by the filler particles in the PP matrix and/or by the interfacial debonding between filler particles and the PP matrix. It was indicated that the presence of CaCO 3 filler could augment the ductility of composites locally, resulting in higher fracture energy in the crack initiation and propagation of the PP/CaCO 3 composites in a certain CaCO 3 content range.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44729/1/10853_2004_Article_BF00357345.pd

Assessment of the Bill Emerson Memorial Cable-Stayed Bridge based on Seismic Instrumentation Data

In this study, both ambient and earthquake data measured from the Bill Emerson Memorial Cable-stayed Bridge are reported and analyzed. Based on the seismic instrumentation data, the vibration characteristics of the bridge are investigated and used to validate a three-dimensional Finite Element (3-D FE) model of the bridge structure. The 3-D model is rigorous and comprehensive, representing realistic dynamic behaviors of the bridge. It takes into account the geometric nonlinear properties caused by cable sagging and soil-foundation-structure interaction in the Illinois approach of the bridge. The FE model is successfully verified and validated by using the natural frequencies and mode shapes of the bridge extracted from the measured data. With the calibrated model, time history analyses were performed to assess the condition of the bridge structure under a postulated design earthquake. Since the FE model is developed according to as-built drawings, the calibrated model can be used as a benchmark for safety evaluation and health monitoring of the cable-stayed bridge in the future

Gate-controlled reversible rectifying behaviour in tunnel contacted atomically-thin MoS2_{2} transistor

Atomically-thin 2D semiconducting materials integrated into van der Waals heterostructures have enabled architectures that hold great promise for next generation nanoelectronics. However, challenges still remain to enable their full acceptance as compliant materials for integration in logic devices. Two key-components to master are the barriers at metal/semiconductor interfaces and the mobility of the semiconducting channel, which endow the building-blocks of ${pn}$ diode and field effect transistor. Here, we have devised a reverted stacking technique to intercalate a wrinkle-free h-BN tunnel layer between MoS$_{2}$ channel and contacting electrodes. Vertical tunnelling of electrons therefore makes it possible to suppress the Schottky barriers and Fermi level pinning, leading to homogeneous gate-control of the channel chemical potential across the bandgap edges. The observed unprecedented features of ambipolar ${pn}$ to ${np}$ diode, which can be reversibly gate tuned, paves the way for future logic applications and high performance switches based on atomically thin semiconducting channel.Comment: 23 pages, 5 main figures + 9 SI figure

Effect of Preharvest Spraying of Diethyl Aminoethyl Hexanoate on Membrane Lipid Metabolism of Grapes during Storage

In order to investigate the effect of preharvest spraying of diethyl aminoethyl hexanoate (DA-6) on membrane lipid metabolism in ‘Kyoho’ grapes during postharvest storage, distilled water (control) and 50 mg/L DA-6 were used to spray grapes at the veraison stage. The grapes were harvested when they were ripe, stored at (0 ± 1) ℃ and relative humidity of 65%–70%, and evaluated for cell membrane related indicators of grape skin after 0, 20, 30, 40, 50, and 60 days. The results showed that compared with the control group, DA-6 treatment effectively inhibited the increase in the relative permeability of cell membrane during postharvest storage, maintained the activities of lipoxygense (LOX), lipase and phospolipase D (PLD), inhibited the decrease of phosphatidylcholine and phosphatidylinositol content and the increase of phosphatidyl acid content, and maintained a high relative content of unsaturated acids such as linoleic acid and linolenic acid as well as saturated fatty acids such as stearic acid, behenic acid, arachidic acid and palmitoleic acid, consequently maintaining the degree of unsaturation of fatty acids at a high level. Additionally, DA-6 treatment suppressed the expression of the LOX, Lipase, and PLD genes. In summary, preharvest spraying of 50 mg/L DA-6 can delay the senescence and prolong the storage period of ‘Kyoho’ grapes by effectively relieving the membrane lipid metabolism during storage

Characteristics and metabolic potential of biliary microbiota in patients with giant common bile duct stones

BackgroundEndoscopic retrograde cholangiopancreatography (ERCP) is an effective minimally invasive operation for the management of choledocholithiasis, while successful extraction is hampered by large diameter of stones. Emerging studies have revealed the close correlation between biliary microbiota and common bile duct stones (CBDS). In this study, we aimed to investigate the community characteristics and metabolic functions of biliary microbiota in patients with giant CBDS.MethodsEligible patients were prospectively enrolled in this study in First Affiliated Hospital of Soochow University from February 2022 to October 2022. Bile samples were collected through ERCP. The microbiota was analyzed using 16S rRNA sequencing. Metabolic functions were predicted by PICRUSTs 2.0 calculation based on MetaCyc database. Bile acids were tested and identified using ultra performance liquid chromatography-tandem mass spectrometry.ResultsA total of 26 patients were successfully included into final analysis, 8 in giant stone (GS) group and 18 in control group. Distinct biliary microbial composition was identified in patients with giant CBDS, with a significantly higher abundance of Firmicutes at phylum level. The unique composition at genus level mainly consisted of Enterococcus, Citrobacter, Lactobacillus, Pyramidobacter, Bifidobacterium and Shewanella. Pyramidobacter was exclusively found in GS group, along with the absence of Robinsoniella and Coprococcus. The contents of free bile acids were significantly higher in GS group, including cholic acid (98.39μmol/mL vs. 26.15μmol/mL, p=0.035), chenodesoxycholic acid (54.69μmol/mL vs. 5.86μmol/mL, p=0.022) and ursodeoxycholic acid (2.70μmol/mL vs. 0.17μmol/mL, p=0.047). Decreasing tendency of conjugated bile acids were also observed. Metabolic pathways concerning cholelithiasis were abundant in GS group, including geranylgeranyl diphosphate biosynthesis, gluconeogenesis, glycolysis and L-methionine biosynthesis.ConclusionsThis study demonstrated the community structure and metabolic potential of biliary microbiota in patients with giant CBDS. The unique biliary microbial composition holds valuable predictive potential for clinical conditions. These findings provide new insights into the etiology of giant CBDS from the perspective of biliary microbiota

Altered gut microbiota in temporal lobe epilepsy with anxiety disorders

IntroductionPatients with epilepsy are particularly vulnerable to the negative effects of anxiety disorders. In particular, temporal lobe epilepsy with anxiety disorders (TLEA) has attracted more attention in epilepsy research. The link between intestinal dysbiosis and TLEA has not been established yet. To gain deeper insight into the link between gut microbiota dysbiosis and factors affecting TLEA, the composition of the gut microbiome, including bacteria and fungi, has been examined.MethodsThe gut microbiota from 51 temporal lobe epilepsy patients has been subjected to sequencing targeting 16S rDNA (Illumina MiSeq) and from 45 temporal lobe epilepsy patients targeting the ITS-1 region (through pyrosequencing). A differential analysis has been conducted on the gut microbiota from the phylum to the genus level.ResultsTLEA patients' gut bacteria and fungal microbiota exhibited distinct characteristics and diversity as evidenced by high-throughput sequencing (HTS). TLEA patients showed higher abundances of Escherichia-Shigella (genus), Enterobacterales (order), Enterobacteriaceae (family), Proteobacteria (phylum), Gammaproteobacteria (class), and lower abundances of Clostridia (class), Firmicutes, Lachnospiraceae (family), Lachnospirales (order), and Ruminococcus (genus). Among fungi, Saccharomycetales fam. incertae sedis (family), Saccharomycetales (order), Saccharomycetes (class), and Ascomycota (phylum) were significantly more abundant in TLEA patients than in patients with temporal lobe epilepsy but without anxiety. Adoption and perception of seizure control significantly affected TLEA bacterial community structure, while yearly hospitalization frequency affected fungal community structures in TLEA patients.ConclusionHere, our study validated the gut microbiota dysbiosis of TLEA. Moreover, the pioneering study of bacterial and fungal microbiota profiles will help in understanding the course of TLEA and drive us toward preventing TLEA gut microbiota dysbiosis