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Simple synthesis and high performance are eternal pursuit for polymers. To lower the curing temperature, lower the melt viscosity and improve the processability of high performance phthalonitrile resins, a solvent‐free method was applied to synthesize three from different phenols. Their chemical structure was confirmed by FTIR and NMR spectra, the curing behavior was investigated by DSC and rheology. It was found that the polymerization of phthalonitrile groups could be effectively promoted by benzoxazine moieties and the curing temperature of phthalonitrile groups dropped to around 240°C. Consequently, owing to the high curing reactivity, polymers obtained at relatively low curing temperature possessed high crosslinking density and extremely high thermal stability. P‐apn‐200, which was cured at 200°C, showed 5 wt% weightloss temperature (Td5) of 472°C and char yield (Yc) of 75.77% at 800°C. Moreover, the polymers obtained after curing at 280°C showed superior dimensional stability, CN‐apn‐280 showed extremely low linear expansion coefficient (CTE) of 10.7 ppm/°C. And mP‐apn‐280 showed HR capacity of 3.99 J/g‧K, peak HRR of 4.0 W/K and total HR of 0.8 kJ/g. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to explore the relationship between circulating metabolites and postmenopausal osteoporosis (PMOP) and to assess the mediating role of inflammatory factors. Methods: Utilizing summary-level data from genome-wide association studies (GWAS) and employing a Mendelian Randomization approach, a two-sample MR analysis was conducted to assess the relationship between circulating metabolites and PMOP. Additionally, a two-step MR was used to quantify the mediating impact of inflammatory factors on the effect of circulating metabolites on PMOP. Results: The results revealed a significant association between certain metabolites and the risk of PMOP, notably the ratio of free cholesterol to total lipids in very large VLDL particles (OR: 1.399, 95% CI: 1.002-1.954, p = 0.048) and IL-16 (OR: 0.773, 95% CI: 0.608-0.983, p = 0.036). IL-16 was found to partially mediate the impact of circulating metabolites on PMOP, with a mediation effect of 10.4%. Conclusion: This study underscores the crucial role of circulating metabolites and inflammatory factors in PMOP pathogenesis. A causal relationship between circulating metabolites and PMOP was established, with IL-16 mediating some effects. These findings hold promise for clinical applications in early detection, personalized medicine, and the identification of therapeutic targets for PMOP. [ABSTRACT FROM AUTHOR]

Introduction: Gut microbiota (GM) has been implicated in gestational diabetes mellitus (GDM), yet longitudinal changes across trimesters remain insufficiently explored. Methods: This nested cohort study aimed to investigate GM alterations before 24 weeks of gestation and their association with GDM. Ninety-three Chinese participants provided fecal samples during the first and second trimesters. Based on oral glucose tolerance tests, 11 participants were classified as GDM, and 82 as non-diabetic (ND). Using 16S rRNA sequencing, we analyzed both cross-sectional and longitudinal differences in GM structure between those two groups. Results: In the first trimester, GDM group exhibited lower levels of Bacteroides_H and Acetatifactor compared to ND group (p < 0.05). In the second trimester, GDM individuals showed increased abundance of Fusobacteriota and Firmicutes_D , and genera including Fusobacterium_A and Fournierella , while Anaerotruncus and others decreased (P< 0.05). Inflammation-associated genera like Gemmiger_A_73129 and Enterocloster increased, while Megamonas decreased in overweight or obese GDM women, which was not identified in normal-weight women. The ratios of relative abundance of genera Streptococcus , Enterocloster , and Collinsella exceeded 1.5 in the GDM group, particularly in overweight or obese individuals. Inflammatory pathways related to African trypanosomiasis and Staphylococcus aureus infection were predicted to be up-regulated in overweight or obese GDM individuals but not in normal-weight GDM women. Discussion: This study suggests that GM of women with GDM undergoes significant alterations between the first and second trimesters, potentially linked to inflammation, with more pronounced changes observed in overweight or obese individuals. [ABSTRACT FROM AUTHOR]

In this study, graphite tailings produced in Luobei County, Heilongjiang Province, were used as a sustainable aggregate to replace river sand (0%, 25%, 50%, 75%, 100%) in UHPC for the preparation of ultra-high-performance concrete (UHPC). The experimental results showed that the incorporation of 75% graphite tailings caused a significant increase in the wet bulk density of UHPC mortar. The workability of UHPC decreased monotonically with the increase in graphite tailing substitution rate, and wet bulk density decreased by 28.42% with 100% graphite tailings (compared with no graphite tailings). The incorporation of 75% graphite tailings helped to improve the compressive and flexural strengths as well as the durability of UHPC. Compared with the UHPC without graphite tailings, the 28 d compressive and flexural strengths increased by 8.82% and 7.28%, respectively, and the chloride ion electrical flux decreased by 19.49%. XRD and thermogravimetric analysis data indicate that the incorporation of graphite tailings did not change the type of hydration and that the incorporation of graphite tailings helped to increase the degree of hydration within the UHPC matrix. MIP and SEM showed that 75% graphite tailings helped to reduce the porosity and the number of harmful pores inside the matrix. The 100% graphite tailings treatment replacing river sand decreased the economic cost of UHPC by up to 23.78%. [ABSTRACT FROM AUTHOR]

Primary patellar dislocation has a certain recurrence rate after either conservative or surgical treatment, and the optimal treatment for patients with primary patellar dislocation of different ages remains unclear. This study aims to compare the clinical efficacy of surgical and conservative treatments for primary patellar dislocation across different age groups. According to the Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) checklist, we conducted a systematic search for randomized controlled trials. We searched the PubMed, EMBASE, Cochrane Library, and Web of Science databases for randomized controlled trials of primary patellar dislocation treated surgically or conservatively up to January 2023. Data searching, extraction, analysis, and quality assessment were carried out in accordance with the Cochrane Collaboration guidelines. A total of nine studies with 433 patients were included in our study. There was no statistically significant difference between the two treatment modalities in terms of Kujala score, pain score, patient satisfaction, reoperation, and Tegner score. The rate of re‐dislocation after surgical treatment is lower than that after conservative treatment. Subgroup analysis based on mean age showed that when the age was >20 years, Kujala scores were higher after surgical treatment than after conservative treatment (p < 0.0001, 95% confidence interval [CI] = 10.41–21.30). When the age was ≤20 years, the difference in Kujala scores between the two treatment modalities was not statistically significant. When the age was >20 years, the recurrence rate of patellar dislocation was lower after surgical treatment than after conservative treatment (p = 0.009, 95% CI = 0.08–0.70). When the age was ≤20 years, the difference in the recurrence rate of patellar dislocation between the two treatment modalities was not statistically significant. When the age of patients with primary patellar dislocation is ≤20 years, both surgical and conservative treatments result in similar clinical outcomes. When the age is >20 years, better clinical outcomes can be achieved by opting for surgical treatment. Therefore, surgery may be a better option for patients with primary patellar dislocation whose age is >20 years. [ABSTRACT FROM AUTHOR]

Osteoporosis (OP) is a widespread age-related disorder marked by decreased bone density and increased fracture risk, presenting a significant public health challenge. Central to the development and progression of OP is the dysregulation of the mechanistic target of the rapamycin (mTOR)-signaling pathway, which plays a critical role in cellular processes including autophagy, growth, and proliferation. The mTOR-autophagy axis is emerging as a promising therapeutic target due to its regulatory capacity in bone metabolism and homeostasis. This review aims to (1) elucidate the role of mTOR signaling in bone metabolism and its dysregulation in OP, (2) explore the interplay between mTOR and autophagy in the context of bone cell activity, and (3) assess the therapeutic potential of targeting the mTOR pathway with modulators as innovative strategies for OP treatment. By examining the interactions among autophagy, mTOR, and OP, including insights from various types of OP and the impact on different bone cells, this review underscores the complexity of mTOR's role in bone health. Despite advances, significant gaps remain in understanding the detailed mechanisms of mTOR's effects on autophagy and bone cell function, highlighting the need for comprehensive clinical trials to establish the efficacy and safety of mTOR inhibitors in OP management. Future research directions include clarifying mTOR's molecular interactions with bone metabolism and investigating the combined benefits of mTOR modulation with other therapeutic approaches. Addressing these challenges is crucial for developing more effective treatments and improving outcomes for individuals with OP, thereby unveiling the therapeutic potentials of targeting the mTOR-autophagy axis in this prevalent disease. [ABSTRACT FROM AUTHOR]

The widespread distribution of karst landforms has led to a shortage of water resources in Southwest China. Understanding the spatiotemporal variations in and driving factors of evapotranspiration (ET) in this area is crucial for understanding and predicting severe water resource shortage. This study conducted trend analysis using meteorological data from 2003 to 2020 as well as remote sensing products such as Penman–Monteith–Leuning equation version 2 (PML-V2) ET. The factors influencing the spatial distribution pattern of average ET were identified using a geographical detector. Partial correlation analysis was performed to characterize the relationships between ET and the factors governing its variations, determined using the random forest model. The results demonstrated the following: (1) The average ET decreased with increasing latitude and altitude, primarily affected by the landform type in terms of longitude and displaying “W”-shaped fluctuations. Overall, the annual ET exhibited a significant (p < 0.05) increasing trend, with 72.63% of its area under the increasing trend. (2) The results of the geographic detector indicated sunshine duration as the strongest explanatory factor of the spatial distribution of ET, followed by enhanced vegetation index (EVI), landform type, precipitation, elevation, slope, and aspect. Instead of an individual factor, the interplay between multiple factors more considerably influenced the spatial distribution pattern of ET. (3) The EVI exhibited an overall increasing trend, with a significant increase over 73.59% of the study area and a positive correlation with ET. Thus, the increase in EVI had the strongest impact on ET in the study area, which was further confirmed by the results of the random forest model for 42.92% of the study area. Thus, the present findings clarify the spatiotemporal variations in and driving factors of ET in Southwest China and can serve as a benchmark for policies aiming to develop and manage water resources in this region.

The conversion of inert N2 and CO2 into urea by electrocatalytic technology not only reduces the cost of urea synthesis in future, but also alleviates the environmental pollution problem caused by carbon emission in traditional industrial production. However, facing downside factors such as strong competitive reactions and unclear reaction mechanism, the design of high-performance urea catalysts is imminent. This study demonstrates that W18O49 system doped heteronuclear metals (TM = Fe, Co, Ni) can effectively solve the problem of competitive adsorption between N2 and CO2 and realize the co-adsorption of N2 and CO2 at diverse sites. Their theoretical limiting voltages for urea production on TM-W18O49 (TM = Fe, Co, Ni) systems are −0.46 V, −0.42 V and −0.52 V, respectively. The results are all lower than that of the contrastive voltage in pristine W18O49 system (-0.91 V), further indicating the rationality and necessity of single-atom doped strategy for the co-reduction of two molecules. Specially, Co-W18O49 can theoretically inhibit the side reactions of NRR, CO2RR, and HER, which deserve future experimental exploration in future. The study suggests that doping heteronuclear metal into transition metal oxides is a feasible scheme to solve competitive adsorption and improve catalytic performance. [ABSTRACT FROM AUTHOR]

Osteoporosis (OP) is a common metabolic bone disease characterized by low bone mass, decreased bone mineral density, and degradation of bone tissue microarchitecture. However, our understanding of the mechanisms of bone remodeling and factors affecting bone mass remains incomplete. Sirtuin1 (SIRT1) is a nicotinamide adenine dinucleotide-dependent deacetylase that regulates a variety of cellular metabolisms, including inflammation, tumorigenesis, and bone metabolism. Recent studies have emphasized the important role of SIRT1 in bone homeostasis. This article reviews the role of SIRT1 in bone metabolism and OP and also discusses therapeutic strategies and future research directions for targeting SIRT1. [ABSTRACT FROM AUTHOR]