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Two new eudesmane sesquiterpenoids [(−)-(1 R ,5 S ,6 R ,8 S)−1-hydroxy- nor -eudesm-11-ene-2-one (1) and (−)-(1 S ,5 S ,6 R ,8 R)−6-hydroxyeudesm-11-ene-2-one (2)] were isolated from the aerial parts of Pogostemon cablin. Compound 1 is an unusual 1- nor -eudesmane, and its skeleton structure is similar to that of compound 2. The molecular structures and absolute conformations of the two new sesquiterpenoids were determined by NMR spectroscopy, X-ray diffraction analysis, NMR data calculations and electronic circular dichroism (ECD) calculations. The neuroprotective activity of the isolates in an H 2 O 2 -induced PC12 cell model was also assessed, and the results show that both compounds exhibit good neuroprotective effects. [Display omitted] • Two new eudesmane sesquiterpenoids were isolated from Pogostemon cablin. • Their absolute configurations were elucidated by NMR data, X-ray diffraction, NMR data calculations and ECD calculations. • Compounds 1 and 2 may play a role in reducing the cytotoxicity of H 2 O 2 on PC12 cells. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of maternal selenium-enriched yeast (SeY) supplementation during late gestation and lactation on sow performance, transfer of selenium (Se) and redox status, and gut microbiota community, as well as on the gut health of offspring. Seventy pregnant sows on day 85 of gestation were randomly allocated to the following two treatments: (1) sows who were fed a basal diet (basal diet contained 0.3 mg/kg Se as Na2SeO3, n = 35); (2) and sows who were fed a SeY-supplemented diet (basal diet with 0.2 mg/kg Se as SeY, n = 35). The offspring piglets were only cross-fostered within the group on day 3 of lactation (L3) according to the pig farm epidemic prevention policy. The plasma, milk, and feces samples from 10 sows, as well as plasma and intestinal samples per treatment, were collected on L1 and L21, respectively. Our results showed that maternal SeY supplementation increased the first week average weight and ADG of piglets (p < 0.05). Compared with the CON group, the SeY supplementation increased the Se content in the plasma and milk of sows and the plasma of piglets on L1 and L21 (p < 0.05). In addition, in sows, the levels of fat in the milk on L21, the level of IgA, T-AOC, and GSH-Px in the plasma on L21, and the level of T-AOC and GSH-Px in the colostrum were increased, while the MDA content was decreased in the plasma on L1 and in the colostrum and milk on L14 (p < 0.05). In the piglet plasma, the levels of IgA on L1 and L21, GSH-Px on L1, and GSH on L21 were increased, while the MDA content was decreased on L1 (p < 0.05). Maternal SeY supplementation up-regulated the small intestinal protein abundances of MUC1, E-cadherin, ZO-1, occludin, and claudin and activated the Nrf2/Keap1 signaling pathway in weaned offspring piglets. The 16S rRNA sequencing results showed that fecal microbiota had distinct separations during lactation, and the relative abundances of unclassified_f_Lachnospiraceae, Prevotaceae_UCG-001, and Lachnospiraceae_NK4A136_group were increased on L1. Collectively, the current findings suggest that maternal SeY supplementation during late gestation and lactation could improve the piglet's growth performance, Se status, antioxidant capacity and immunoglobulins transfer at the first week of lactation, as well as alter the fecal microbiota composition by increasing antioxidative-related and SCFA-producing microbiota in sows. These changes contributed to enhancing the small intestinal barrier function and activating the Nrf2/Keap1 pathway in offspring. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of betaine supplementation in sows and/or their offspring's diets on the redox status, immune and inflammatory levels, colonic barrier function, and colonic microbial community of offspring piglets. Thirty-six Bama mini-sows on day 3 of gestation and their weaned offspring piglets (28 d of age) were randomly allocated to the following treatments: (1) sows and their weaned offspring fed the basal diet (control group, Con group); (2) sows fed the basal diet with 3.50 kg/t betaine, and their weaned offspring fed the basal diet (sows betaine group, SB group); (3) sows fed the basal diet with 3.50 kg/t betaine, and their weaned offspring fed the basal diet with 2.50 kg/t betaine (sow-offspring betaine group, S-OB group). Six offspring piglets from each group were selected to collect plasma and colon samples on d 30, 60, and 90 after weaning. Compared with the Con group, the plasma levels of IgA, IgM, GSH-Px, and SOD during d 30–90 after weaning, IFN-α, T-AOC, and GSH on d 30 and 60 after weaning were increased, while MDA during d 30–90 after weaning was decreased in the SB and S-OB groups (p < 0.05). In addition, the plasma levels of IFN-γ on d 60 and T-AOC on d 30 after weaning were higher in the S-OB group than those in the Con group (p < 0.05). In the colon, betaine supplementation increased plasma T-AOC, GSH, and SOD levels while decreasing MDA concentration (p < 0.05). Betaine supplementation improved the colonic protein abundances of ZO-1, occludin, and claudin in offspring and activated the Nrf2/Keap1 signaling pathway while inhibiting the TLR4-NF-κB/MAPK signaling pathway on d 90 after weaning. The 16S rRNA sequencing results showed that betaine supplementation altered colonic microbiota composition by increasing the relative abundances of Verrucomicrobia and Actinobacteria in the SB group while decreasing proinflammatory-associated microbiota abundances (Tenericutes, Prevotella, and Parabacteroides) (p < 0.05). Collectively, these findings suggest that dietary betaine supplementation in sows and/or their offspring could improve offspring piglets' redox status and immune and anti-inflammatory levels and enhance the colonic barrier function by activating Nrf2/Keap1 and inhibiting TLR4-NF-κB/MAPK signaling pathways. [ABSTRACT FROM AUTHOR]

Parabadiella is considered the earliest trilobite representative in South China and was originally recovered from the mid-upper part of the Guojiaba Formation, in Liangshan section. Previous studies suggested that the earliest brachiopod co-occurred with the oldest trilobite, and the Parabadiella–Eoobolus association from the Xihaoping Member (Cambrian Series 2, Stage 3), in southern Shaanxi was considered the first trilobite–brachiopod assemblage zone in South China. Therein, brachiopods occur together with trilobites recovered in Well JS103 seemingly extending the First Appearance Datum deeply in the lower Cambrian at the central Yangtze Platform. Well JS103 is a shale gas exploration well that targets the lower Cambrian Jiulaodong Formation in southern Sichuan Basin. The uppermost fossiliferous layers are siliciclastic rocks nearly 10 metres thick. Here, two distinct trilobite zones are found, including the lower Parabadiella Zone and the upper Wutingaspis–Eoredlichia Zone. Additionally, the lowermost part of the Guojiaba Formation is poorly fossiliferous, and ranges from 200 to 250 metres in thickness. Thus, the discovery of the brachiopod–trilobite assemblage provides new insights into the biostratigraphy in Sichuan and is of great potentials for biostratigraphic correlation of the siliciclastic rocks in the western margin of the Yangtze Platform. [ABSTRACT FROM AUTHOR]

Background: Several epidemiological articles have reported the correlations between anti-osteoporosis medication and the risks of fractures in male and female subjects, but the specific efficacy of anti-osteoporosis medication for male subjects remains largely unexplored.Objective: The aim of this study was to evaluate the correlation between anti-osteoporosis medication and the risk of fracture in relation to low bone mass [including outcomes of osteoporosis, fracture, and bone mineral density (BMD) loss] in male subjects analyzed in studies within the updated literature.Methods: Randomized controlled trials (RCTs) that analyzed the effectiveness of a treating prescription for male subjects with osteoporosis (or low BMD) and that focused on the outcomes of fracture were included. Relevant studies from Embase, Web of Science, PubMed, and Chinese database of CNKI were retrieved from inception to January 30th, 2019. Two staff members carried out the eligibility assessment and data extraction. The discrepancies were settled by consultation with another researcher. We calculated the pooled relative risks (RRs) based on 95% confidence intervals (CIs).Results: Twenty-seven documents (28 studies) with 5,678 subjects were identified. For the category of bisphosphonates, significant results were observed in pooled analyses for decreased risk of the vertebral fracture domain (RR, 0.44 [95% CI, 0.31–0.62]), nonvertebral fracture domain (RR, 0.63 [95% CI, 0.46–0.87]), and clinical fracture domain (RR, 0.59 [95% CI, 0.48–0.72]) compared with those of controls. Participants with bisphosphonates had a 56% (95% CI = 38–69%) lower risk of vertebral fractures, 37% (95% CI = 13–54%) lower risk of nonvertebral fractures, and 41% (95% CI = 28–52%) lower risk of clinical fractures. Furthermore, meta-analyses also demonstrated a decreased risk of the vertebral fracture domain via treatment with risedronate (RR, 0.45 [95% CI, 0.28–0.72]) and alendronate (RR, 0.41 [95% CI, 0.23–0.74]), but not with calcitriol, calcitonin, denosumab, ibandronate, monofluorophosphate, strontium ranelate, teriparatide, or zoledronic acid, compared with that of controls.Conclusions: This systematic review confirms that bisphosphonates were connected with a decreased risk of vertebral fractures, nonvertebral fractures, and clinical fractures for male subjects with osteoporosis. Future research is needed to further elucidate the role of nonbisphosphonates in treating fractures of osteoporosis subjects.

To investigate the optimal longitudinal seismic energy dissipation system of straddle-type monorail-cum-road long-span cable-stayed bridges, the Niutianyang Bridge was selected as the engineering background, and the explicit time-domain dimension-reduced iteration method was adopted to carry out nonlinear time-history analysis. To consider the dynamic characteristics of longitudinal movable supports, the static and dynamic responses of four kinds of energy dissipation systems were studied, including longitudinal unconstrained, elastic cable, viscous damper, and speed lock-up devices. The damping effect of four types of schemes in which viscous dampers were installed at piers or towers was analysed, and the parameters of the viscous dampers were optimised. The influences of the straddle-type monorail train braking force and the running vibration of the straddle-type monorail traffic on the parameters of the viscous dampers were analysed. This study shows that the viscous damper system had the lowest bending moment at the bottom of the tower and a smaller displacement response, and the energy dissipation was the best. Each viscous damper had the highest energy dissipation efficiency when they are installed only at the main tower. The damping effect was better when the damping coefficient c ranged from 3500 to 5000 kN⋅m/s−α and the velocity exponent α ranged from 0.35 to 0.5. The static friction of the straddle-type monorail-cum-road long-span cable-stayed bridge support can resist the trains’ braking force, and the parameters of the viscous damper can be selected regardless of train braking. A suitably large value of velocity exponent α may be required to increase the working velocity of the viscous damper to reduce the damper’s participation in the process of the train crossing the bridge.

The metadynamic recrystallization behavior of Cr-Co-Ni-Mo ultrahigh-strength martensitic stainless steel was studied in a double-pass isothermal compression test, and a metadynamic recrystallization kinetics model for softening was established. The results showed that the metadynamic recrystallization softening rate of the steel not only depended on the deformation temperature and strain rate but was also related to the dynamic precipitation and the local shear bands in the steel. When the deformation temperature was below 1050 °C, the dynamically precipitated M _6 C carbides pinned the grain boundaries and hindered metadynamic recrystallization. When the steel was deformed at a deformation temperature of 1000∼1050 °C and a strain rate of 1.0∼5.0 s ^−1 , a large number of local shear bands were generated. The local shear bands increased the number of nucleation sites for dynamic recrystallization and enhanced the softening rate of metadynamic recrystallization.

The static recrystallization (SRX) behavior of an ultrahigh-strength stainless steel (UHSSS) was investigated via double-hit isothermal compression tests. The results revealed that the kinetics of static recrystallization and the corresponding microstructural evolution were not only prominently influenced by the deformation parameters and initial microstructures but also suppressed due to the precipitation of M _6 C carbides below 1050 °C, which sufficiently pinned the boundaries. Numerical models for predicting the recrystallized fraction and grain sizes were proposed based on the experimental results. The kinetics model could predict the process of SRX in the deformation temperature range from 1050 °C to 1150 °C well, whereas there were some deviations between the predictions and experimental results due to the interaction of the M _6 C carbides and SRX when the deformation temperature was below 1050 °C.