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There has been a lack of precise methods for monitoring and evaluating the entire process of gas fracturing. However, strain monitoring can effectively record the real-time initiation and propagation of cracks. By studying the strain response of borehole walls during high-pressure gas impact, the relationship between crack formation and strain response during the fracturing process can be clarified, enabling the identification of the optimal fracturing angle. A true triaxial experimental system for high-pressure gas fracturing of coal and rock was used, and experiments were conducted at five different impact angles (0, 30, 45, 60, 90°) to investigate crack morphology, pressure curves, and strain response characteristics of the borehole walls. The experimental results revealed that: ① As the impact angle increased, the crack morphology of coal and rock exhibited a pattern that was initially complex but later became simpler. ② The gas pressure during the fracturing process passed through four stages: an increase, a sharp drop, accumulation, and steady release. ③ The strain data for the borehole walls were predominantly tensile, and the strain curve displayed two distinct peaks: the first peak occurred 0.1 seconds after the pressure curve reached its peak, coinciding with the formation of the main crack; the second peak was generally associated with the propagation and expansion of the main crack. ④ When the impact angle was 45°, a more complex crack network tended to form within the specimen, resulting in the most effective fracturing.

We developed a contemporary cardioprotective medication using silver nanoparticles (AgNPs) loaded with Spinacia oleracea to treat isoproterenol (ISO)-induced myocardial infarction in mice, focusing on the PPAR-γ/NF-κB pathway. The physicochemical techniques, such as Fourier-transform infrared spectroscopy, field emission scanning electron microscopy, ultraviolet–visible spectroscopy, and energy dispersive X-ray analysis, were employed to characterize the AgNPs. In the in vivo experiment, myocardial infarction was induced in mice by administering ISO subcutaneously at a dose of 40 mg/kg every 12 h for a total of three times. The mice were divided into five groups in a random manner: (1 and 2) ISO + AgNPs at varying doses (10 and 20 μg/mL) and time points; (3) ISO; and (4) control. Following the treatment, cardiac function was assessed through electrocardiogram, as well as biochemical and histochemical analyses. In the study, we examined the inflammatory reactions and cell death in human coronary artery endothelial cells exposed to lipopolysaccharide (LPS). The PPAR-γ/NF-κB activation by LPS and the resulting cytokine production were checked using real-time PCR and western blot techniques. The typical ST segment depression in myocardial infarction mice is significantly inhibited by the administration of AgNPs. Additionally, the treatment with AgNPs leads to a significant improvement in ventricular wall infarction, a decrease in mortality rate, and inhibition of myocardial injury marker levels. Furthermore, the application of AgNPs resulted in a decrease in the inflammatory environment within the hearts of mice with myocardial infarction. This effectively prevented the increase in TNF-α, IL-1β, and IL-6. The gene expression normalization of PPAR-γ/NF-κB/IκB-α/IKKα/β and PPAR-γ phosphorylation could potentially be linked to the advantageous impacts of AgNPs. In the context of an in vitro experiment, the administration of AgNPs demonstrated a notable decrease in cell death and inflammation cytokines expression inhibition. The myocardial infarction mice in the pre + post-ISO group appear to experience more noticeable cardioprotective effects from the treatment with AgNPs than those in the post-ISO group. Our research findings demonstrate that AgNPs possess cardioprotective efficacies in ISO-induced myocardial infarction. This beneficial effect may be attributed to the PPAR-γ activation and the NF-κB signaling inhibition. Consequently, our study presents a novel remedial approach for myocardial infarction treatment in clinical settings.

Summary: Background: Since 1992, when recombinant hepatitis B vaccine was introduced in China, government health officials have used nationally representative serological surveys to monitor progress in prevention and control of hepatitis B. In 2020, we conducted the fourth seroepidemiological survey, which for the first time included medical evaluation of the clinical status of HBsAg positive subjects over the age of 15 and their medical management. We report survey results in comparison with the three previous surveys. Methods: Consistent with previous national surveys, the 2020 survey used a stratified, three-stage cluster random sampling method to select for evaluation 1-69-year-olds in 120 national disease surveillance points. Blood samples were tested for HBsAg, anti-HBV surface antigen (anti-HBs), and anti-HBV core antigen (anti-HBc) in the National Hepatitis Laboratory of the Institute for Viral Disease Control and Prevention of China CDC. HBsAg positive subjects aged ≥15-year were evaluated for evidence of liver disease, and through face-to-face questionnaire-based survey, we determined the healthcare management cascade of HBV-infected individuals. Findings: HBsAg prevalence in 1–69-year-olds was 5.86%; in children 1–4 years of age, seroprevalence was 0.30%; 75 million people were living with HBV nationwide. Among HBsAg-positive individuals 15 years and older, expert medical examination found that 78.03% were HBsAg carriers with no evidence of liver damage, 19.63% had chronic HBV with liver enzyme abnormalities, 0.84% had evidence of cirrhosis, and 0.15% had evidence of liver cancer. 59.78% of HBsAg + individuals were aware that they were positive before the survey, 30 million were unaware; 38.25% of those who knew they were positive (17 million) had medical indications for antiviral treatment, and 17.33% of these individuals (3 million) were being treated with antivirals. Interpretation: The decline in HBsAg prevalence in the general population, from 9.72% in 1992 to 5.86% in 2020, and in 1–4-year-olds from 9.67% in 1992 to 0.30% in 2020, shows progress that continues on track toward WHO targets for prevention of new infections. Implementation of acceptable strategies to identify infected individuals and offer long-term medical monitoring and management will be important to prevent complications from hepatitis B infection and for meeting WHO cascade-of-care targets. Funding: The study was funded by the Major Science and Technology Special Project of China’s 13th 5-Year Plan (grant no. 2017ZX10105015); Central finance-operation of public health emergency response mechanism of Chinese Center for Disease Control and Prevention (131031001000200001, 102393220020010000017).

ObjectiveTo investigate the current status and influencing factors of hand hygiene practices among primary healthcare workers， and to provide a reference for improving hand hygiene behavior in primary healthcare institutions.MethodsA self-designed questionnaire was used to conduct a survey among medical staff of seven community health service centers in Jiading District， Shanghai， using a cluster random sampling method. The data collected were subjected to descriptive statistics， reliability and validity tests， correlation analysis， and structural equation model fitting.ResultsA statistical difference in hand hygiene compliance was found among medical staff with varying occupational types and educational levels （P

This study proposes to explore the coal mechanics and seepage characteristics under the coupling of water-saturation, freeze-thaw and different temperatures. The original coal of 9105 working face in Wangzhuang Coal Mine was taken as the research object, and non-contact digital image processing was used to carry out the triaxial loading test of the coal rock under the conditions of liquid nitrogen freeze-thaw and microwave heat injection. Results showed that: ① in the original coal samples after freeze-thaw, water-saturated, and water-saturated freeze-thaw conditions and gradient temperature treatment, there is increase in the compressive strength, modulus of elasticity, Poisson's ratio, and shear strain value of the coal rock; ② the original coal rock in the compression density, elasticity, yield and destruction of the four stages of the stress concentration phenomenon shows no obvious developmental changes, but by water-saturated, water-saturated freeze-thaw, water-saturated freezing and thawing conditions of 100 ℃ and 150 ℃ temperature treatment, the local stress of the specimen concentrates in the destruction phase with obvious amplification; ③ compared with the initial permeability of the original coal rock, the initial permeability of the coal sample underwent a small increase of 1.44×10-3μm2 after the liquid nitrogen freeze-thaw treatment. After the water-saturated liquid nitrogen freeze-thaw, water-saturated liquid nitrogen freeze-thaw treatment at 50 ℃ and 100 ℃, there is more significant increase in the initial permeability of the coal rock, and after the water-saturated liquid nitrogen freeze-thaw treatment at 150 ℃, the initial permeability of the coal sample underwent a significantly higher increase and reaches 7.40×10-3μm2. The study provide references for increasing the permeability of gas in deep low-permeability coal beds, which could improve the efficiency of downhole gas extraction.

Unmanned driving & remote driving transportation business in Xiwan Coal Mine requires three-dimensional coverage of wireless network with large bandwidth and low latency in light-load test area, heavy-load test area and whole mining area. In view of the difficulties of site landing, high frequency of site relocation and complex wireless environment in coal mining area, this paper puts forward a scheme of "700 MHz + 2.6 GHz + 4.9 GHz" triple frequency networking, which effectively solves the problem of safe, stable and efficient 5G network coverage in the whole mining area, and meets the bandwidth and delay business needs of unmanned driving & remote driving. At the same time, in order to further enhance the bandwidth of coal mining area (coal roof, stone roof), a 4.9 GHz time slot flip 1D3U scheme is proposed, which changes three downward time slots to uphill time slots, making the proportion of downward timeslot to uphill time slot from 5:3 to 1:3. After the implementation of the triple-frequency networking scheme, the proportion 50 Mbit/s upstream edge rate in the whole coal mine business area is more than 99%, and the average time delay is less than 20 ms. After the implementation of the 4.9 GHz timeslot flip 1D3U scheme, the peak rate of ascending in the core mine area increased from 290 Mbit/s to around 600 Mbit/s, which expanded the upstream bandwidth.

Objective To explore the distribution of immune cell subsets in patients with chronic graft-versus-host disease (cGVHD) and investigate the predictive values of specific cell subsets sorted by surface markers in the development of cGVHD. Methods From October 2020 to July 2021, 58 patients who received hematopoietic stem cell transplantation (HSCT) from the Hematology Medical Center of the Second Affiliated Hospital of the Army Medical University were collected in this study. Flow cytometry was used to detect the ratio of immune cell subpopulations in the cGVHD patients (cGVHD group, n=43) and those without (control group, n=15) who received allogeneic HSCT during the same period. Primary diagnoses of the recruited patients included acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), myelodysplastic syndromes (MDS), severe aplastic anemia (SAA), and β-thalassemia major. The median time to occurrence of cGVHD was 178.5 (47~1 328) d. Peripheral blood (PB) samples were collected for each patient when cGVHD occurred during follow-up or on the day of follow-up during the course of the disease. Results The percentages of PB regulatory T cells (Tregs) and transitional B cells were significantly reduced in the cGVHD group (P < 0.05), and that of CD19+ B lymphocytes was higher than the control group. The percentage of Tregs differed from the cGVHD patients with different severities (P < 0.05). The percentage of Th17-like cells in the patients with moderate cGVHD was significantly higher than patients with mild cGVHD. CD19+ B lymphocytes showed higher percentage in the patients with mild and moderate cGVHD. In the comparison among different targeted organs of cGVHD, only the Tregs percentage was significantly lower in the patients with skin and liver damage than control group, while the percentage of follicular helper T cells in the patients with skin and liver damage was significantly higher than those only having mucous membrane or eye organ involvement. Conclusion Distribution of immune cell subsets after HSCT is an important reference marker for the diagnosis, treatment and prognosis of cGVHD. Treg cells and transitional B cells which are sorted with a special combined strategy of surface markers play specific guiding roles in the pathogenesis, severity and damage of targeted organs of cGVHD.

Objective To construct a mouse model of skin-dominant chronic graft-versus-host disease (cGVHD). Methods BALB/c mice were irradiated with lethal dose and then received a mixture of bone marrow and spleen cells transplantation from B10.D2 donor mice. Then the clinical manifestations, pathological features of the mice and cell subsets of targeted organs were observed to evaluate the establishment of model. Results The clinical manifestations of the model mice mainly involved skin depilation, sclerosis, dandruff, scab, as well as arched back and joint stiffness due to skin shrinkage and sclerosis. The clinicopathological scores were increased with the progression of cGVHD, while the model mice showed no obvious manifestations of intestinal cGVHD. Moreover, increase of collagen deposition and decrease or even disappearance of hair follicles was observed on the histopathologic sections of skin, while other targeted organs showed no major alterations. T cell subsets analysis indicated that Th1 cells, CD4+IL-13+T cells and Tc1 cells were closely related to the disease progression. Conclusion The skin-dominant cGVHD mouse model is successfully established, with skin damage and fibrosis as main pathological changes.

Objective To determine the prophylactic effect of human umbilical cord mesenchymal stem cells (HUCMSCs) on murine acute graft-versus-host disease (aGVHD) and preliminarily explore its mechanism. Methods In order to establish a mouse model of aGVHD, the male BALB/c mice were transplanted with bone marrow cells and spleen lymphocytes from male C57BL/6 mice after receiving 7.5 Gy total body irradiation (TBI) on the day of allogeneic hematopoietic stem cell transplantation (allo-HSCT). The mice were divided into BM group and aGVHD group, receiving 500 μL cell suspension containing 5×106 bone marrow cells or 5×106 bone marrow cells and 5×106 spleen cells, respectively, by tail vein. Their survival rate, clinical score and loss of body weight were assessed, chimerism was detected by flow cytometry, and pathological changes of target organs (lung, liver, colon, small intestine) were detected by HE staining. The HUCMSCs at passage 4 were collected and transplanted into aGVHD+MSCs group of BALB/c mice. The mice were then divided into aGVHD group (model group), aGVHD+MSCs group (5×106 bone marrow cells and 5×106 spleen cells and 5×105 HUCMSCs). Besides, the serum concentration of IFN-γ and TNF-α were detected by ELISA, and the infiltration and apoptosis of lymphocytes were detected by flow cytometry. Results Compared with the BM group, the aGVHD group showed a decreased survival rate, higher clinical score, and much obvious body weight loss (P < 0.05) and severer pathological injuries (P < 0.05). The mice achieved complete chimerism after transplantation. The aGVHD+MSCs group showed increased survival rate, lower clinical score and slighter pathological injuries (P < 0.05), the serum concentrations of IFN-γ and TNF-α were decreased (P < 0.05), and the apoptosis of CD4+ T cells in target organs was increased while the count was decreased (P < 0.05). Conclusion HUCMSCs infusion effectively prevent the development of murine aGVHD after allo-HSCT through mediating the apoptosis of lymphocytes to decrease their infiltration in target organs and regulating the secretion of inflammatory factors.

Recent morphological and molecular evidence has challenged classical interpretations of eubrachyuran phylogeny and evolution. Complete mitochondrial genomes of two species of potamid freshwater crabs, Sinopotamon yaanense and Sinopotamon yangtsekiense were obtained using next-generation sequencing. The results revealed a novel gene order with translocations of a five-gene block and a tRNA gene in comparison to available brachyuran mitochondrial genomes. DNA sequence comparisons position the Potamidae, a primary freshwater crab family, outside of the clade for the traditional heterotreme families, and closer to the clade that includes the thoracotreme families of grapsoid and ocypodoid crabs. Mitogenomic comparisons using rapid next-generation sequencing and a much wider taxonomic sample are required for a high-resolution examination of the phylogenetic relationships within the Eubrachyura.

Cogging torque is one of the unique problems of permanent magnet generators. Its main cause is the uneven distribution of the generator’s magnetic permeability, which directly affects the starting and running performance of the generator. The study of cogging torque suppression methods is of great significance for improving the operating stability and service life of generators. Through the analysis of the principle of cogging torque, an optimization method for the amplitude of cogging torque based on Taguchi algorithm for the two parameters of pole arc coefficient and skew angle is established. And the finite element analysis method is used to quantitatively compare the characteristic parameters of the generator model before and after the optimization by Taguchi algorithm. The results show that when the pole arc coefficient and the angle of the chute are in the optimal value at the same time, the cogging torque of the generator can be greatly reduced, and its air gap magnetic density waveform and induced electromotive force waveform are ideal, which provides a research method for the design and parameter optimization of large megawatt permanent magnet synchronous wind turbines.