To investigate the differences and applicability of free silica detection methods of different crystal forms in dust, and to provide a basis for the selection of various methods.
From December 2021 ...to June 2022, dust samples from 20 enterprises in different industries in 18 cities in Henan Province were randomly selected as the investigation objects. X-ray diffraction (XRD) method was used to analyze the samples and classify the samples. Based on GBZ/T 192.4-2007 "Determination of Dust in the Air of Workplace-Part 4: Content of Free Silica in Dust", pyrophosphate method and infrared spectrophotometry were used for quantitative determination. The measured results were analyzed by paired sample
test to evaluate the advantages and disadvantages of the two methods and their applicable scope.
The XRD results of 20 dust samples could be divided into α, β, γ crystal types and the mixed type of α and γ. There was no significant difference between pyrophosphate method and infrared spectrophotometry (
=0.180). The pyro
Purpose of the present study was to evaluate the effect of surface roughness on the time-dependent wear performance of lithium disilicate (LD) glass-ceramic.
Friction pairs (pin and disk specimens) ...were prepared by IPS e.max® Press lithium disilicate glass-ceramic. The lateral faces of friction pairs (N = 12) were grinded with silicon carbide papers, and 6 friction pairs were polished with a 0.25 μm diamond suspension after grinding. The friction pairs were tested for wear performance using a pin-on-disk tribometer with 10 N for 1.02 × 106 wear cycles in artificial saliva. Wear analysis of the pin and disk was performed with a 3D profilometer. The microstructure and worn surface morphology were examined with scanning electron microscopy. One-way analysis of variance and Tukey's post-hoc pairwise comparison were used to analyze the wear data.
The two group LD friction pairs presented strong time-dependent wear performance. The polished group (GP) exhibited a high wear rate and extensive surface wear during 0–1 × 105 cycles (running-in wear stage). The wear rate, height loss and surface roughness were obviously lower than those of grinded group (GG) in running-in wear stage. However, these wear parameters were similar during the steady wear stage. The worn surface topographies of the pin and disk in GP were smoother at the same cycle before the GG entering the steady wear stage.
Running-in, which means the initial stage of wear process, is a critical period to determine the final wear loss and surface degradation, when compare the wear behavior of lithium disilicate ceramic with different initial surface states. Ceramic layer with smooth contact area leads to low wear rate and short running-in wear stage.
Summary
The derived feathering phenotype beard in domestic birds is an ideal resource to investigate the genetic mechanisms controlling feather development and differentiation. In the present study, ...we performed a GWAS and QTL linkage analysis on the trait of beard in Beijing fatty chicken. One major QTL (1.2–1.9 Mb) was identified that could explain 34% of the phenotypic variation. The copy number variation that was copied from the region (GGA27:3 578 409–3 592 890 bp) containing homebox B7 (HOXB7) and homebox B8 (HOXB8) was validated to be only exhibited in the genome of bearded chickens. Protein–protein interaction analysis indicated that HOXB7 and HOXB8 proteins could highly interact with the HOXB family members, including HOXB4, HOXB5 and HOXB6, whose genomic locations near HOXB7 and HOXB8 suggested that they may regulate their family members to involve in the formation of the beard trait in chickens. Overall, our work provides basic data for understanding the mechanisms regulating beard development and differentiation.
Metabolic dysfunction-associated steatohepatitis (MASH), formerly known as nonalcoholic steatohepatitis (NASH), is an advanced stage of metabolic fatty liver disease. The pathogenic mechanisms of ...MASH center on hepatocyte injury and the ensuing immune response within the liver microenvironment. Recent work has implicated TREM2
macrophages in various disease conditions, and substantial induction of TREM2
NASH-associated macrophages (NAMs) serves as a hallmark of metabolic liver disease. Despite this, the mechanisms through which NAMs contribute to MASH pathogenesis remain poorly understood. Here, we identify membrane-spanning 4-domains a7 (MS4A7) as a NAM-specific pathogenic factor that exacerbates MASH progression in mice. Hepatic MS4A7 expression was strongly induced in mouse and human MASH and associated with the severity of liver injury. Whole-body and myeloid-specific ablation of
alleviated diet-induced MASH pathologies in male mice. We demonstrate that exposure to lipid droplets (LDs), released upon injury of steatotic hepatocytes, triggered NAM induction and exacerbated MASH-associated liver injury in an MS4A7-dependent manner. Mechanistically, MS4A7 drove NLRP3 inflammasome activation via direct physical interaction and shaped disease-associated cell states within the liver microenvironment. This work reveals the LD-MS4A7-NLRP3 inflammasome axis as a pathogenic driver of MASH progression and provides insights into the role of TREM2
macrophages in disease pathogenesis.
Smilax glabra Roxb. (SGB) is a medicinal plant widely distributed in 17 countries worldwide. It is the primary raw material of the world-famous and best-selling functional food and beneficial tea. ...SGB was first recorded in Ben Cao Jing Ji Zhu of the Southern and Northern Dynasties (420-589 AD) and was reported for nutritional and medicinal properties for thousands of years. This review searched PubMed, Web of Science, and other databases for relevant literature on SGB species until April 2022. It aims to provide more integrated thinking, detailed awareness, and better knowledge of SGB. More than 200 chemical components have been discovered, including favonoids, phenolic, phenolic acids, stilbenes, organic acids, phenylpropanoids, and others. Previous studies have demonstrated that SGB and its active ingredients show a wide range of pharmacological effects, including anti-infective, anti-cancer, antiinflammatory, antioxidant, cardiovascular protection, etc. However, many studies on the biological activity of this plant were mainly based on crude extracts and active ingredients, and there is a lack of clinical studies and toxicity studies to support the development of drug design, development, and therapy. In summary, this review will provide specific and valuable suggestions and guidelines for further research and application of this plant in the medicinal field. Keywords: Smilax glabra Roxb, astilbin, traditional usages, phytochemical constituents, pharmacological properties, clinical applications
Traditional thermal tempering was applied to lithium disilicate (LD) glass-ceramic specimens with bar-like and disc-like shapes. The tempering process was conducted by heating the specimens to a ...temperature below the dynamic softening point, and then rapid cooling in silicone oil with different temperatures ranging from room-temperature to 300 °C to regulate the cooling rate. Effect of the oil-temperature on mechanical behavior of the tempered glass-ceramic was investigated. For the tempering at the lower oil-temperature (e.g., at room-temperature), it was found that the LD glass-ceramic specimens with both the bar-like and disc-like shapes could be remarkably strengthen and toughen, however, obvious anisotropy in fracture toughness was displayed by the specimens with the bar-like shape. With increasing the oil-temperature up to 250 °C, the mechanical anisotropy of the bar-like specimens could be significantly alleviated without much loss of the strengthening effect. The results can provide references for improving reliability of mechanical behavior for the tempered LD glass-ceramic by regulating the cooling condition according to specimen geometry.
•A lithium disilicate glass-ceramic was effectively strengthen and toughen by traditional thermal tempering.•Obvious anisotropy in mechanical behavior was displayed by the tempered glass-ceramic in bar-like shape.•The anisotropy could be alleviated without much loss of the strengthening effect by regulating the cooling rate.
Aims/hypothesis Liver X receptors (LXRs) are important transcriptional regulators of lipid homeostasis and proliferation in several cell types. However, the roles of LXRs in pancreatic beta cells ...have not been fully established. The aim of this study was to investigate the effects of LXRs on pancreatic beta cell proliferation. Methods Gene expression was analysed using real-time RT-PCR. Transient transfection and reporter gene assays were used to determine the transcriptional activity of LXRs in pancreatic beta cells. Cell viability and proliferation were analysed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), DNA fluorometric, BrdU labelling and ³Hthymidine incorporation assays. Cell cycle distribution was investigated by flow cytometry analysis. Adenovirus-based RNA interference was used to knockdown LXRα, LXRβ and p27 in MIN6 cells and mouse islets. Results We found that both Lxrα (also known as Nr1h3) and Lxrβ (also known as Nr1h2) were expressed and transactivated the LXR response element in HIT-T15 and MIN6 cells. Activation of LXRs dose-dependently inhibited pancreatic beta cell viability and proliferation. This was accompanied by beta cell cycle arrest at the G1 phase. Furthermore, LXR activation increased levels of the p27 protein by inhibiting its degradation. Knockdown of p27 reversed these effects of LXR activation on growth inhibition and cell cycle arrest. Conclusions/interpretation Our observations indicate that LXR activation inhibits pancreatic beta cell proliferation through cell cycle arrest. A well-known regulator of pancreatic beta cell cycle progression, p27, is upregulated and mediates the effects of LXRs on growth inhibition in beta cells. These observations suggest the involvement of aberrant activation of LXR in beta cell mass inadequacy, which is an important step in the development of type 2 diabetes.
To understand the status of autism spectrum disorder (ASD) cohort studies and explore the feasibility of constructing ASD disease-specific cohorts based on real-world data (RWD).
ASD cohort studies ...published by December 2022 were collected by literature retrieval from major Chinese and English databases. And the characteristics of the cohort were summarized.
A total of 1 702 ASD cohort studies were included, and only 60 (3.53%) were from China. A total of 163 ASD-related cohorts were screened, of which 55.83% were birth cohorts, 28.22% were ASD-specific cohorts, and 4.91% were ASD high-risk cohorts. Most cohorts used RWD such as hospital registries or conducted community-based field surveys to obtain participant information and identified patients with ASD by scales or clinical diagnoses. The contents of the studies included ASD incidence and prognostic risk factors, ASD comorbidity patterns and the impact of ASD on self-health and their offspring's health.
ASD cohort studies in developed countries have been
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