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Poly (m-diethynylbenzene-methylsilane-phenylsilane)(PDMP), the heat-resistant silicon-alkyne resin, was synthesized from m-diethynylbenzene, methylsilane and phenylsilane by the method of Grignard reagent. FT-IR, NMR and GPC were selected to characterize the structure of PDMP resin. The curing behavior was analyzed by DSC and rheometer, and heat performance was measured by TGA. The study shows that heat-resistant of resins first increases and then decrease with the increase of mole ratio of phenylsilane and methylsilane. When the mole ratio comes to 7:4, PDMP's heat-resistant is the best. And the Td5 (5% mass loss temperature) and residual are respectively 654℃ and 90.3% in N2, 574℃ and 34.0% in air after 1000℃.

It is highly desirable, while still challenging, to obtain noble metal nanocrystals with custom capping ligands, because their colloidal synthesis relies on specific capping ligands for the shape control while conventional ligand exchange processes suffer from "the strong replaces the weak" limitation, which greatly hinders their applications. Herein, we report a general and effective ligand exchange approach that can replace the native capping ligands of noble metal nanocrystals with virtually any type of ligands, producing flexibly tailored surface properties. The key is to use diethylamine with conveniently switchable binding affinity to the metal surface as an intermediate ligand. As a strong ligand, it in its original form can effectively remove the native ligands; while protonated, it loses its binding affinity and facilitates the adsorption of new ligands, especially weak ones, onto the metal surface. By this means, the irreversible order in the conventional ligand exchange processes could be overcome. The efficacy of the strategy is demonstrated by mutual exchange of the capping ligands among cetyltrimethylammonium, citrate, polyvinylpyrrolidone, and oleylamine. This novel strategy significantly expands our ability to manipulate the surface property of noble metal nanocrystals and extends their applicability to a wide range of fields, particularly biomedical applications.

Objective: This study aimed to investigate the magnetic resonance imaging (MRI) characteristics of abnormal placental shapes (APS) compared with prenatal ultrasound. Methods: From an initial cohort of 613 women with a high prevalence of placenta accreta spectrum (PAS) disorders, the MRI findings of 27 pregnant women with APS who underwent antenatal ultrasound and MRI examinations before delivery were retrospectively analyzed. The clinicopathological findings were used as the gold standard, and the sensitivity, specificity, and accuracy of antenatal MRI and a multidisciplinary team experienced in diagnosing APS were assessed. Results: The 27 patients diagnosed with APS included 14 cases of succenturiate placenta, eight cases of the bilobed placenta, two cases of the circumvallate placenta, and one case each of placenta chorioangioma, placenta membranacea, and placental mesenchymal dysplasia. The sensitivity and specificity of APS classification with antenatal MRI were 40.74% (11/27) and 97.65% (498/510), respectively. Nonetheless, the multidisciplinary team achieved a higher sensitivity and specificity of up to 96.29% (26/27) and 99.22% (506/510), respectively. Conclusion: We have demonstrated the complementary role of MRI and ultrasound in the detection of placental shapes in the setting of MRI images, highlighting the importance of radiologists communicating with sonographers in the diagnosis of APS. [ABSTRACT FROM AUTHOR]

Background: ISCA1 (Iron–Sulfur Cluster Assembly 1) is involved in the assembly of iron–sulfur (Fe–S) clusters, which are vital for electron transport and enzyme activity. Some studies suggest the potential involvement of ISCA1 in tumor progression through interactions with ferroptosis-related genes (FRGs) and the tumor immune microenvironment (TME). However, there has been no systematic analysis of its role in FRGs and the TME or its predictive value for prognosis and immunotherapy response across different cancer types. Methods: In this study, we analyzed the expression and prognosis of ISCA1 RNA, CNV, methylation, and protein in multiple tumor tissues via data from the TCGA and CPTAC databases and clinical information. We conducted a comprehensive analysis of the correlations between ISCA1 and FRGs, immune-related genes (including immune regulatory genes and immune checkpoint genes), immune cell infiltration, immune infiltration scores, tumor stemness, and genomic heterogeneity. Results: We performed drug prediction and validation through molecular docking and molecular dynamics analysis to identify candidate drugs that could promote or inhibit ISCA1 RNA expression. Our findings revealed that ISCA1 could serve as a biomarker in thyroid carcinoma, play a role with different FRGs in various cell types, and mediate different ligand–receptor pathways for cell–cell communication. Conclusions: Overall, our study highlights the potential of ISCA1 as a novel biomarker for predicting prognosis and immunotherapeutic efficacy in thyroid carcinoma and suggests its potential for developing novel antitumor drugs or improving immunotherapy. [ABSTRACT FROM AUTHOR]

Pancreatic β‐cell damage mediated by apoptosis is believed to be a main trigger of type 1 diabetes mellitus (T1DM), which is proposed as an organ‐specific autoimmune disease mediated by T cells. Nonetheless, the fundamental origins of T1DM remain uncertain. Here, we illustrate that an increase in PLAGL1 expression induces β‐cell apoptosis, as evidenced by mitochondrial membrane impairment and nucleolar degradation. The gene expression levels from cDNA samples were determined using qRT‐PCR method. Western blot and Co‐immunoprecipitation were applied for protein expression and interactions, respectively. Flow cytometry and TUNEL assay were used to detect pancreatic β cell apoptosis. Female NOD/LtJ mice with recent‐onset T1DM has been used in in vivo studies. Glucose‐stimulated insulin secretion (GSIS) and glucose tolerance test (GTT) method is used for islet function assessment. Haematoxylin and Eosin (H&E) and Immunohistochemistry (IHC) were performed to evalute histological improvement of islet beta. Subsequent cytoplasmic DNA accumulation triggers DNA senser, the cyclic guanosine monophosphate‐AMP synthase (cGAS)‐stimulator of interferon genes (STING) pathway. STING activation further stimulates downstream IRF3 and NF‐kB pathways, thus boost type‐I interferon signalling and NF‐kB mediated inflammation. These findings elucidate a molecular mechanism linking PLAGL1 induced cell apoptosis to type‐I interferon signalling and suggest a potential benefit for targeting cGAS/STING in T1DM treatment. [ABSTRACT FROM AUTHOR]

Background Obesity is a crucial risk factor for asthma. Observational studies have examined the association between abdominal obesity and asthma symptoms. This study aimed to investigate the causal relationship between visceral adipose tissue (VAT) and asthma and its potential as an independent indicator. Methods This study utilized data from the National Health and Nutrition Examination Survey spanning 2011–8. Multivariable logistic regression and stratified variable selection were employed to identify associations between asthma and VAT. Moreover, a two-sample Mendelian randomization analysis, using 221 genetic variants as instrumental variables, was conducted to assess this relationship further. Results Our findings indicated that individuals with higher VAT levels were more likely to develop asthma. Visceral obesity remained a significant risk factor for asthma after adjusting for demographic characteristics. Genetic predictions suggest a positive association between VAT and an elevated risk of asthma (odds ratio [OR] = 1.393, 95% confidence interval [CI]: 1.266–1.534, and P  = 1.43E−11). No significant polymorphisms were detected using the Mendelian randomization-Egger intercept test. Conclusions This study presents potential evidence supporting the causal role of VAT in asthma development. Furthermore, the findings from the Mendelian randomization analysis further reinforce the relationship between VAT and asthma risk. Key message What is already known on this topic Obesity is a well-established risk factor for asthma, with previous observational studies examining the association between abdominal obesity and asthma symptoms. What this study adds Individuals with higher visceral fat are more likely to develop asthma. Furthermore, even after adjusting for demographic factors, visceral obesity remains a significant risk factor for asthma. How this study might affect research, practice, or policy This study offers additional evidence associating visceral fat with asthma and further validates the causal relationship between the two conditions. [ABSTRACT FROM AUTHOR]

It has been widely reported that obesity adversely impacts reproductive performance of females. However, the effects of maternal obesity on fetal germ cells remain poorly understood. In the present study, by employing a high‐fat diet (HFD)‐based mouse model, it is discovered that maternal obesity disrupts the chromosomal synapsis and homologous recombination during fetal oogenesis. Moreover, transcriptomic profiling reveales the potential molecular network controlling this process. Of note, the global hypermethylation of genomic DNA in fetal oocytes from obese mouse is detected. Importantly, time‐restricted feeding (TRF) of obese mice not only ameliorate the meiotic defects, but also partly restore the epigenetic remodeling in fetal oocytes. In sum, the evidence are provided showing the deficit fetal oogenesis in obese mother, implicating a mechanism underlying the intergenerational effects of environmental insults. TRF may represent a potentially effective approach for mitigating fertility issues in obese patients. [ABSTRACT FROM AUTHOR]

Graphene foam composite is a promising candidate for advanced thermal management applications due to its excellent mechanical strength, high thermal conductivity, ultra-high porosity and huge specific surface area. In this study, a three-dimensional physical model was developed in accordance with the dodecahedral structure of graphene foam composite. A comprehensive numerical simulation was carried out to investigate the fluid flow and convective heat transfer in open-cell graphene foam composite by using ANSYS Fluent 2021 R1 commercial software. Research results show that, as porosity increases, the pressure gradient for graphene foam composite with circular and triangular cross-section struts is reduced by 65% and by 77%, respectively. At a given porosity of 0.904, when the inlet velocity increases from 1 m/s to 5 m/s, the pressure gradient is increased by 11.3 times and 13.8 times, and the convective heat transfer coefficient is increased by 54.5% and 43% for graphene foam composite with circular and triangular cross-section struts, respectively. Due to the irregularity of the skeleton distribution, the pressure drop in Y direction is the highest among the three directions, which is 8.7% and 17.4% higher than that in the Z and X directions at the inlet velocity of 5 m/s, respectively. The convective heat transfer coefficient in the Y direction is significantly lower than that along the X and Z directions. Furthermore, triangular cross-section struts induce a greater pressure drop but offer less effective heat transfer compared to circular struts. The research findings may provide critical insights into the design and optimization of graphene foam composites, and promote their potential for efficient thermal management and gas/liquid purification in engineering applications. [ABSTRACT FROM AUTHOR]