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Background While the connection between monounsaturated fatty acid (MUFA) intake and non-alcoholic fatty liver disease (NAFLD) has received attention, research in Chinese populations remains scarce. Objective This study aims to evaluate the association between daily MUFA intake and the prevalence of NAFLD in a Chinese population and to estimate the probable threshold of MUFA intake for NAFLD risk. Methods This case-control study employed data from the Dryad database (https://doi.org/10.5061/dryad.8nn2j46), complying with Dryad's terms of service. We collected data from 534 NAFLD patients and 534 healthy controls who underwent medical tests at the First Hospital of Nanping Affiliated to Fujian Medical University between April 2015 and August 2017. A semi-quantitative food frequency questionnaire (SQFFQ) was used to collect individuals' typical food consumption information, and daily MUFA intake was computed. A thorough analytical technique, including baseline characteristics, multivariate statistics, non-linear relationship analysis, and subgroup research, was applied to study the correlation between daily MUFA intake and NAFLD prevalence. Multiple confounding factors, such as age, sex, lifestyle, and other dietary components, were evaluated to estimate the theoretical threshold of MUFA intake for NAFLD risk. Results In the adjusted model, daily MUFA intake was a significant risk factor for NAFLD (OR=1.04, 95%CI=1.02-1.07, P

Abstract Background Reports on coronavirus disease 2019 (COVID-19) in neonates are limited, especially in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) Omicron variant. This study aims to analyze the clinical characteristics and identify risk factors associated with severe COVID-19 in neonates infected with Omicron variant. Methods The study population was represented by neonates with COVID-19, who were admitted to The Affiliated Children’s Hospital of Xi’an Jiaotong University in northwest China, from December 10, 2022 to January 20, 2023. Chinese Center for Disease Control and Prevention (CDC) announced that all local COVID-19 cases were infected with Omicron variant during the study period. Clinical and laboratory data were collected retrospectively. We used logistic regression analysis to investigate the risk factors for severe COVID-19, and derived odds ratios (ORs) and the corresponding 95% confidence intervals (CIs). Results A total of 108 neonates, with median age of 18.1 days (interquartile range 9.4–23.0), were affected by COVID-19, of whom 84 had a mild disease, while 24 a severe one (22.2%). Of them, 6.5% were premature. No deaths were observed in the study population. The most common clinical manifestations were fever (88.9%) and cough (55.6%), with 5 cases (4.6%) complicated by pneumonia. 4 cases (3.7%) received respiratory support, including 2 cases of high-flow oxygen and 2 cases of continuous positive airway pressure. Gestational age at birth (OR: 0.615; 95% CI: 0.393–0.961), neutrophil count (NEU) (OR:0.576; 95% CI : 0.344–0.962) and lymphocyte count (LYM) (OR: 0.159; 95% CI: 0.063–0.401) were independent risk factors for severe COVID-19. The combination of NEU and LYM had the largest receiver operating characteristic area under the curve [0.912 (95% CI:0.830–0.993)] for identifying severe COVID-19, with a sensitivity of 0.833 and a specificity of 0.917. Conclusions The general presentations and outcomes of neonatal COVID-19 caused by Omicron variant were not severe, and very few patients required respiratory support. The simultaneous decrease in NEU and LYM can be used to identify severe infection.

Pre-upsetting deformation is an effective way to optimize the microstructure of plastic forming components and achieve deep modification. In this paper, the pre-upsetting deformation of AZ31 Mg alloy billet was carried out before alternating forward extrusion, and the effect of pre-upsetting deformation temperature on the recrystallization behavior and texture evolution of AZ31 Mg alloy formed by alternating forward extrusion was analyzed. The results showed that the strains generated by the pre-upsetting deformation at different temperatures all leaded to a high dynamic recrystallization (DRX) driving force. This results in a high percentage of recrystallized grains in all pre-upsetting alternating forward extrusion (UAFE) formations. The highest percentage of recrystallized grains 94.5% was observed in U2AFE (pre-upsetting deformation at 623 K). The behavior of DRX has a significant impact on both the distribution and strength of texture. In the case of U2AFE, the maximum basal texture strength is 8.65. This is due to the maximum pole density of the deformed texture, which is composed of non-recrystallized grains and is as high as 9.25. In contrast, the maximum pole density of the recrystallized texture, which is composed of recrystallized grains, is only 8.09. Therefore, non-recrystallized grains play a crucial role in the formation of texture in UAFE. This study provides scientific guidance and technical support for the research of high-performance Mg alloy alternating forward extrusion molding technology.

Objective Sb deposits are characterized by simple mineral assemblage. The ore-forming ages, sources of ore-forming materials, and genesis of Sb deposits are controversial owing to the absence of suitable minerals for analysis. Sb resources in the South China Sb metallogenic region account for over 83% of the national total, with the Dian–Qian–Gui Sb belt in the southwest being an significant component of this region. Methods Taking the Longlin–Xilin Sb–Au mining district of western Guixi in the central part of the Dian–Qian–Gui Sb belt as an example, this paper systematically summarizes the ore-bearing strata, lithology of ore-bearing wall rocks, ore-bearing structures, and the coexistence relationship of Au and Sb deposits in 86 ore deposits (points) in the area. Combined with the geological characteristics of three typical deposits (Maxiong, Longtan, and Mahao) and the spatiotemporal distribution of Jurassic felsic intrusions, the inherent connection between Sb mineralization and clastic rocks and felsic intrusions was explored. Results (1) Statistics and field works show that the most favorable ore-bearing stratum in the Longlin–Xilin mining district is the Lower Devonian Yujian Formation (D1y) , followed by the Lower Triassic Luolou Formation (T1Ll) and the Middle Triassic Banna Formation (T2b). The lithologies most conducive to mineralization are carbonaceous shale, pyrite-rich sandstone, and siltstone. The Sb content in these strata or lithologies is tens or even hundreds of times higher than the crustal abundance, which has the potential for Sb mineralization. (2) Within the NWW–SEE trending Nongsang–Shijiazhai fault zone in the Longlin area, the middle and late Jurassic felsic intrusions, which have consistent spatiotemporal occurrences with Sb and Au deposits, can directly contribute to antimony mineralization (as sources of Sb and S) and indirectly influence it (as a heat source), both favoring the formation of antimony deposits. (3) Statistical results show that Sb, Au, and Sb–Au deposits account for 48%, 46%, and 6% in the Longlin–Xilin district, respectively. This suggests that the ore-forming fluids for Sb and Au in the study area may originate from different sources. We also can not rule out the possibility that Sb and Au deposits derive from the same fluid. In the latter case, the precipitation of stibnite consumes H2S in the ore-forming fluid, destabilizing the Au complex in the solution and resulting in localized Au precipitation. This competition between Sb and Au in the fluid for H2S leads to a negative correlation in the grades of Sb and Au in coexisting deposits. (4) The study area experienced NS-striking compression in the Indosinian period, followed by the NW–SE shortening in the middle–late Jurassic. The intersection of NWW–SEE and NE–SW faults is the favorable ore-bearing space. The NWW–SEE faults displayed strike-slip movement in response to the NW–SE shortening, whereas the NE–SW faults exhibited transpression. Consequently, the NE–SW faults are less conducive to Sb mineralization compared to the NWW–SEE faults. The distribution direction of the NWW–SEE Douhuang–Xilin fault aligns with the axial direction of the main folds in the area, with most fault planes trending northward, displaying horizontal scratches, silicification, and extensional characteristics. The intersection of the Dohuang–Xilin fault and the NE–SW fracture exhibits significant Sb anomalies. Conclusion Based on the above studies, the promising areas we propose for Sb prospecting in Longlin–Xilin mining district are (1) Black shale and pyrite-rich siltstones of the Yujiang Formation in the core of the Xinzhou anticline as the key strata; (2) The periphery of the concealed intrusions within the NWW–SEE Nongsang–Shijaizhai fault (Longlin County) and the intersection area of the NWW–SEE Douhuang–Xilin fault and the NE–SW fault as the favorable areas. [ Significance ] The findings provide new insights into the genesis and metallogenic regularities of Sb–Au deposits in the study area, enriching the theoretical understanding of Au mineralization processes.

The construction of early warning model of customer churn in e-commerce platform can help e-commerce enterprises in China to strengthen the risk prevention of customer churn, improve efficiency of customer management and resolve the crisis of customer churn. Therefore, this paper analyses the definition basis and evaluation method of customer churn, and clarifies the function and content of early warning customer churn. By using the K-means clustering analysis of sample data, the early warning level of customer churn risk is categorized. By taking the established index system data as the input layer data of neural network, the early warning model of customer churn risk of e-commerce platform based on neural network is constructed. The test results show that the accuracy of the model is 100%, which can provide reference for the early warning research of customer churn risk in the e-commerce industry of China.

The optimal configuration of strength and ductility was the first choice in Mg-alloys plate forming. A rolling method with adding the hard plate and unique component structure design was proposed to achieve a symmetrical gradient structure from two upmost surfaces to the center of the AZ31 Mg-alloys plate during a single rolling pass. The microstructure evolution and mechanical properties of symmetrical gradient structure plates were studied. The results indicate that Mg-alloy plates' strength and tensile ductility reached 267 MPa and 26.1%, respectively. In the fine-grain region, the proportion of high-angle grain boundary was 56.4%, and the recrystallization structure was 57.3%. In the coarse-grain region, high-grain boundaries and recrystallization decreased to 42.9% and 42.1%, respectively. Both prismatic slip and pyramidal slip in the CG region were easier to initiate, which leads the interaction of multidirectional twins. The geometrically necessary dislocations mainly accumulate at the boundary of the different region. The fracture morphology showed a gradient distribution of dimples. The crack was deflected in the process of extension, which also leads high ductility of Mg-alloy. The design strategy provides a new idea for producing the high-performance plate with through-thickness symmetrical gradient structure.

Bacteremia frequently occurs in patients with acute cholangitis, which could increase the risk of mortality. This single-center retrospective observational study was conducted from July 2013 to July 2020 to evaluate the predictive value of platelet index for bacteremia at admission for acute cholecystitis. A total of 285 patients with acute cholangitis were divided into bacteremia group and non-bacteremia group. The incidence of bacteremia in acute cholangitis was 48.42%. The bacteremia group had more grade III patients, higher 30d mortality rate [17(12.32%) vs 8(5.44%), p = .040] and higher incidence of thrombocytopenia [76(55.07%) vs 35(23.81%), p

With the continuous development of data centers and information technology equipment, data center energy consumption continues to increase, China’s data center energy consumption has accounted for 4% of the power consumption of society as a whole, while the data center cooling system accounts for 30–50% of the data center energy consumption. At the same time, with the development of new high-energy chips, the traditional cooling methods have been unable to meet the requirements of IT equipment cooling, so how to reduce the energy consumption of data centers, especially the cooling system energy consumption, and to meet the cooling requirements of data centers with high heat flux density is becoming the focus of research in the field of data centers. In order to solve the data center cooling system of high energy consumption and high heat flow density needs, immersion cooling technology came into being, this paper is mainly on the data center immersion cooling technology research, and the use of the current situation is introduced and explained, compared to the single-phase immersion cooling technology and two-phase immersion cooling technology cooling principle, the current state of development and use of the prospects for elaboration, while the data center immersion cooling system waste heat utilization is explored, providing readers with a wide range of data center cooling system. At the same time, the utilization of waste heat in the data center immersion cooling system is discussed, providing readers with extensive and detailed background knowledge of data center immersion cooling technology.

【Objective】 Increasing and stabilizing carbon in coarse-textured soils is important to improve their stability and fertility. The purpose of this paper is to investigate how soil amendment with organic materials and clay minerals can achieve these goals. 【Method】 We took spinach as a model crop, and compared eight treatments by amending the soil with woody peat (HW), biochar (HB), lignite (HC), humic acid (HH), woody peat + bentonite (HWb), woody peat + illite (HWa) and woody peat + kaolinite (HWg), respectively. Not amending the soil was taken as the control (H0). In each treatment, we measured crop growth as well as the changes in soil physical and chemical properties. 【Result】 Compared with H0, HW, HB, HC and HH improved the growth and yield of the spinach, as well as physical and chemical properties of the soil. In particular, HB increased the net photosynthetic rate, plant height and leaf of the spinach during the harvest period by 21.5%, 23.5%, 69.5% and 70.9%, respectively, and soil organic matter and total nitrogen content by 236.2% and 20.7%, respectively, compared to H0. In comparison, HH reduced soil pH by 16.8% and increased crop yield by 4.7% during the harvest period, compared to H0. Combined with clay mineral amendment, HWb, HWa and HWg increased crop yield by 22.7%, 9.0%, and 9.0%, respectively, and soil organic matter by 33.5%, 2.4%, and 27.0%, respectively, compared with HW without clay mineral amendment. 【Conclusion】 Amending the soil with organic materials alone, biochar was most effective in improving soil fertility and crop yield. For combined amendment with organic materials and clay minerals, amending the soil with woody peat and swelling and shrinking clay mineral bentonite at 2:1 ratio worked best for boosting crop growth while in the meantime improving soil fertility.

The reproductive lifespan in humans is regulated by a delicate cyclical balance between follicular recruitment and atresia in the ovary. The majority of the small antral follicles present in the ovary are progressively lost through atresia without reaching dominance, but this process remains largely underexplored. In our study, we investigated the characteristics of atretic small antral follicles and proposed a classification system based on molecular changes observed in granulosa cells, theca cells, and extracellular matrix deposition. Our findings revealed that atresia spreads in the follicle with wave-like dynamics, initiating away from the cumulus granulosa cells. We also observed an enrichment of CD68+ macrophages in the antrum during the progression of follicular atresia. This work not only provides criteria for classifying three stages of follicular atresia in small antral follicles in the human ovary but also serves as a foundation for understanding follicular degeneration and ultimately preventing or treating premature ovarian failure. Understanding follicular remodeling in the ovary could provide a means to increase the number of usable follicles and delay the depletion of the follicular reserve, increasing the reproductive lifespan.

The similar scale model experiment can provide some reference for the research and development of naval gun weapons. This paper takes the naval gun bracket as an example to explain. Based on the dimensional analysis, equation analysis and finite element method, the modal parameter similarity relationship between the original model for bracket and the shrinkage ratio model is established. The results show that the error of predicting the natural frequency of the original model based on similarity relation is less than 2% comparing with the results of finite element numerical simulation, and the error is less than 10% comparing with the experimental results, and the mode of shrinkage model is close to that of the original model. It is proved that the theoretical method in this paper is feasible and practical in engineering. Therefore, the vibration characteristics of the original model can be estimated by analyzing the vibration characteristics of the carrier shrinkage ratio model, which provides a reference for ship gun designers.

Articular cartilage defect repair is a problem that has long plagued clinicians. Although mesenchymal stem cells (MSCs) have the potential to regenerate articular cartilage, they also have many limitations. Recent studies have found that MSC-derived exosomes (MSC-Exos) play an important role in tissue regeneration. The purpose of this study was to verify whether MSC-Exos can enhance the reparative effect of the acellular cartilage extracellular matrix (ACECM) scaffold and to explore the underlying mechanism. The results of in vitro experiments show that human umbilical cord Wharton's jelly MSC-Exos (hWJMSC-Exos) can promote the migration and proliferation of bone marrow-derived MSCs (BMSCs) and the proliferation of chondrocytes. We also found that hWJMSC-Exos can promote the polarization of macrophages toward the M2 phenotype. The results of a rabbit knee osteochondral defect repair model confirmed that hWJMSC-Exos can enhance the effect of the ACECM scaffold and promote osteochondral regeneration. We demonstrated that hWJMSC-Exos can regulate the microenvironment of the articular cavity using a rat knee joint osteochondral defect model. This effect was mainly manifested in promoting the polarization of macrophages toward the M2 phenotype and inhibiting the inflammatory response, which may be a promoting factor for osteochondral regeneration. In addition, microRNA (miRNA) sequencing confirmed that hWJMSC-Exos contain many miRNAs that can promote the regeneration of hyaline cartilage. We further clarified the role of hWJMSC-Exos in osteochondral regeneration through target gene prediction and pathway enrichment analysis. In summary, this study confirms that hWJMSC-Exos can enhance the effect of the ACECM scaffold and promote osteochondral regeneration.

Tissue engineering provides a promising avenue for treating cartilage defects. However, great challenges remain in the development of structurally and functionally optimized scaffolds for cartilage repair and regeneration. In this study, decellularized cartilage extracellular matrix (ECM) and waterborne polyurethane (WPU) were employed to construct WPU and WPU-ECM scaffolds by water-based 3D printing using low-temperature deposition manufacturing (LDM) system, which combines rapid deposition manufacturing with phase separation techniques. The scaffolds successfully achieved hierarchical macro‐microporous structures. After adding ECM, WPU scaffolds were markedly optimized in terms of porosity, hydrophilia and bioactive components. Moreover, the optimized WPU-ECM scaffolds were found to be more suitable for cell distribution, adhesion, and proliferation than the WPU scaffolds. Most importantly, the WPU-ECM scaffold could facilitate the production of glycosaminoglycan (GAG) and collagen and the upregulation of cartilage-specific genes. These results indicated that the WPU-ECM scaffold with hierarchical macro‐microporous structures could recreate a favorable microenvironment for cell adhesion, proliferation, differentiation, and ECM production. In vivo studies further revealed that the hierarchical macro‐microporous WPU-ECM scaffold combined with the microfracture procedure successfully regenerated hyaline cartilage in a rabbit model. Six months after implantation, the repaired cartilage showed a similar histological structure and mechanical performance to that of normal cartilage. In conclusion, the hierarchical macro‐microporous WPU-ECM scaffold may be a promising candidate for cartilage tissue engineering applications in the future.

The overburden movement law of the upward fully mechanized working face is different from that of the horizontal working face. The roof collapses frequently, which brings a great test to the stability of the working face support. The existing research on the safe mining of the upward fully mechanized working face mainly focuses on the influence of the change of the mining angle on the overburden movement law, and there is a lack of systematic research on the force characteristics of the roof and floor. In order to solve the above problems, taking the 8102 upward fully mechanized working face in Ruilong Mine as the background, the UDEC numerical simulation software is used to analyze the overburden movement law and roof fracture characteristics at different advancing distances of the upward fully mechanized working face. In the upward working face, affected by the inclination angle and mining method, the bottom coal stress is most concentrated, and the working face has obvious characteristics of initial pressure and periodic pressure. Compared with the nearly horizontal fully mechanized working face, the periodic pressure step is obviously reduced, the peak strength of the overburden is relatively low, the roof is not easy to form a structure, the pressure is more frequent, and the mine pressure appears more intense. The step distance of the first collapse of the direct roof of 8102 working face is 25 m, the step distance of the initial pressure of the basic roof is 40 m, and the step distance of the periodic pressure is 10-15 m. The existing calculation methods of using the roof-support mechanical relationship to determine the working resistance of support are relatively cumbersome. Many methods are not practical when applied to the engineering site. By comparing the advantages, disadvantages and practicality of several commonly used support working resistance calculation methods, it is concluded that the dynamic load calculation method is the most suitable method for calculating the working resistance of the support according to the actual working conditions of 8102 working face. The method has the characteristics of accurate calculation results and easy selection of parameters. It is determined that the maximum working resistance of the support of this working face is 6 359 kN/frame, and the support of this working face with a working resistance greater than 7 066 kN can meet the support requirements. The results of engineering application have proved the correctness of using dynamic load calculation method to calculate the working resistance of the support of 8102 working face.

Intracranial hemorrhage (ICH) is one of the most common cerebrovascular disease. At present, there is still a lack of drugs with definite curative effects for the treatment of intracranial hemorrhage. Microglia is a type of immune cell that specifically exists in the central nervous system. In the acute phase of intracranial hemorrhage, microglia is rapidly activated and can dynamically transform between M1 phenotype (pro ⁃ inflammatory) and M2 phenotype (repair). These two different polarization states suggest that microglia plays a complicated role in the pathophysiological process of secondary neuroinflammation after intracranial hemorrhage. Therefore, this is also an important target for exploring drugs for the treatment of intracranial hemorrhage. This article reviews the surface markers of microglia after intracranial hemorrhage, polarization phenotype, phagocytic hematoma, and potential connections with neurons, astrocytes, and oligodendrocytes, in order to find the possibility of treating intracranial hemorrhage by regulating the function of microglia. doi：10.3969/j.issn.1672⁃6731.2021.02.003

Gas drainage by drilling is the main method of gas drainage. Based on this, gas drainage drilling with different diameters has been carried out. The study on the evolution characteristics of the surrounding plastic zone during the process shows that under the influence of drilling disturbance, expansion and deformation occurs around the hole, resulting in plastic zone, elastic zone and original stress zone; at the same time, the distribution of tangential stress around the five boreholes successively experienced a process of sharp increase, slow decrease until stress equilibrium. The larger the hole diameter, the farther the maximum point of stress around the hole is from the center of the hole; and it is found that the larger the hole diameter, the wider the width of the plastic zone. That is to say, the wider the pressure relief range around the borehole, the more adsorbed gas will be resolved into the free state, resulting in the expansion of the gas drainage radius; at the same time, according to the field test, it is found that when the width of the borehole plastic zone increases, the effect of gas extraction is significantly improved with the increase of pressure relief range around the hole.

Abstract Background With the rapid development of whole embryo freezing technology, more and more frozen-thawed embryo transfer (FET) was used in assisted reproductive technology. However, the best FET program for elderly women has not been finalized. We intended to explore the reproductive outcomes of traditional hormone replacement treatment and a gonadotropin-releasing hormone agonist (GnRHa) combined with hormone replacement treatment in the frozen-thawed embryo transfer cycle of elderly patients. Methods In this retrospective analysis, we analyzed 1264 elderly patients (aged 38 years or older) who underwent FET at three reproductive centers between 2015 and 2017. According to the endometrial preparation protocol, we divided the patients into a GnRHa combined with hormone replacement treatment (GnRHa-HRT) group and traditional hormone replacement treatment (HRT) group. The clinical pregnancy, ongoing pregnancy, live birth, and abortion rates were compared between groups. Results One-way analysis of variance of the two groups revealed no significant difference in the clinical (33.58% vs. 37.15%) and ongoing pregnancy rates (19.40% vs. 25.10%) between the GnRHa-HRT and HRT groups. The live birth rate (17.54% vs. 24.10% p = 0.0229) of the GnRHa-HRT group was lower than that of the HRT group, whereas the abortion rate (45.56% vs. 32.97% p = 0.0252) was higher than that of the HRT group. However, multivariate analysis showed no significant difference in the live birth rate (p = 0.1333) or abortion rate (p = 0.1881) between the GnRHa-HRT and HRT groups. The number of embryos transferred, level of the embryo, and age and ovarian reserve of the patient significantly affected final reproductive outcomes. Conclusion A GnRH agonist combined with hormone replacement therapy did not improve the reproductive outcomes of frozen-thawed embryo cycles in elderly patients.

In order to intuitively reflect the evolution process of the cracks on the surface of similar material samples and the location and shape of the cracks, sand, cement, gypsum and other materials are used to make similar material samples, and the non-contact strain measurement system is used to observe and study the uniaxial compression state, the whole process of the destruction of samples of similar materials. The test results show that compared with the traditional test method, the digital image correlation technology has obvious advantages. The full-field strain cloud image obtained by this method can better reflect the evolution characteristics of the cracks in the failure process of the similar material samples; the “X”-shaped deformation concentrated zone on the sample surface is taken to measure points, and the strain curve of each measuring point is analyzed by VIC-3D analysis software, and the deformation characteristics of the deformation concentrated zone on the sample surface are obtained; compared with the axial strain rate, the change characteristics of the surface strain rate of the specimen at each stage are obtained.

Introduction: Desmoplastic infantile ganglioglioma (DIG) and desmoplastic infantile astrocytoma (DIA) are rare benign childhood intracranial tumors that are classified under neural and mixed glioneuronal tumors. Although many authors have written on surgical treatment of these disease conditions and indicated satisfactory outcomes, no author have written on the postoperative formation of a subdural hydroma after surgery. Case presentation: We present two cases of DIG and DIA infants in whom we achieved total or subtotal tumor resection and observed postoperative hydroma as complications. Their main symptoms were vomiting, seizures and head enlargement. In both cases magnetic resonance imaging (MRI) revealed huge solid-cystic mass located in left frontal, temporal and parietal lobes. Histopathological staining confirmed the diagnosis of DIG and DIA in both cases. A second surgery may be required in patients with this kind of postoperative complication if clinical and radiological imaging evaluation reveal deteriorating of the patient's condition otherwise conservative treatment usually gives a total resolution of this complication. Conclusion: The pathophysiology of this occurrence after surgery is as the result of a potential space created after excision of tumor and subsequent influx of CSF into the potential space between the subdural. Keywords: Hydroma, Desmoplastic, Infantile, Ganglioglioma, Astrocytoma, Postoperative

Biomaterials play a core role in cartilage repair and regeneration. The success or failure of an implanted biomaterial is largely dependent on host response following implantation. Host response has been considered to be influenced by numerous factors, such as immune components of materials, cytokines and inflammatory agents induced by implants. Both synthetic and native materials involve immune components, which are also termed as immunogenicity. Generally, the innate and adaptive immune system will be activated and various cytokines and inflammatory agents will be consequently released after biomaterials implantation, and further triggers host response to biomaterials. This will guide the constructive remolding process of damaged tissue. Therefore, biomaterial immunogenicity should be given more attention. Further understanding the specific biological mechanisms of host response to biomaterials and the effects of the host-biomaterial interaction may be beneficial to promote cartilage repair and regeneration. In this review, we summarized the characteristics of the host response to implants and the immunomodulatory properties of varied biomaterial. We hope this review will provide scientists with inspiration in cartilage regeneration by controlling immune components of biomaterials and modulating the immune system.

Injury of articular cartilage can cause osteoarthritis and seriously affect the physical and mental health of patients. Unfortunately, current surgical treatment techniques that are commonly used in the clinic cannot regenerate articular cartilage. Regenerative medicine involving stem cells has entered a new stage and is considered the most promising way to regenerate articular cartilage. In terms of theories on the mechanism, it was thought that stem cell-mediated articular cartilage regeneration was achieved through the directional differentiation of stem cells into chondrocytes. However, recent evidence has shown that the stem cell secretome plays an important role in biological processes such as the immune response, inflammation regulation, and drug delivery. At the same time, the stem cell secretome can effectively mediate the process of tissue regeneration. This new theory has attributed the therapeutic effect of stem cells to their paracrine effects. The application of stem cells is not limited to exogenous stem cell transplantation. Endogenous stem cell homing and in situ regeneration strategies have received extensive attention. The application of stem cell derivatives, such as conditioned media, extracellular vesicles, and extracellular matrix, is an extension of stem cell paracrine theory. On the other hand, stem cell pretreatment strategies have also shown promising therapeutic effects. This article will systematically review the latest developments in these areas, summarize challenges in articular cartilage regeneration strategies involving stem cells, and describe prospects for future development.

Viscous fingering (VF) occurs when a more viscous fluid is displaced by a less viscous one in porous media or in Hele-Shaw cells. Generally, VF can be divided into two types: immiscible VF and miscible VF. The typical immiscible finger is wider than the equivalent miscible finger because of interfacial tension. Recently, it has been pointed out that an effective interfacial tension (EIT) is present even in miscible systems when there is a steep concentration gradient of chemical species at the interface. The effects of EIT on miscible VF have so far mainly been studied numerically showing that the fingers become wider owing to EIT. Here, we perform an experimental investigation of the effects of EIT on miscible VF by establishing two solution systems that have different concentration differences but the same viscosity contrast. One is a glycerol solution with a concentration of 99 wt. % and water and has a higher water concentration difference of ∆Cw = 99 wt. %. The other is a polymer solution with a concentration of 8.5 wt. % and water and has a lower water concentration difference of ∆Cw = 8.5 wt. %. We show by direct measurement with a spinning drop tensiometer that the glycerol–water system exhibits greater EIT, and we demonstrate experimentally that typical fingers with high EIT become wider than those with low EIT. We suggest that under the experimental condition employed, the VF in the glycerol–water system with high EIT exhibits a characteristic property of immiscible VF, although it has generally been regarded as a typical representative of classical miscible VF.

To study the effect of tunnel section mutation on the time and temperature of smoke spreading to the air inlet and outlet, Pyrosim fire simulation software was used to establish different slope of the tunnel, length and location of sectional mutation of different tunnel sections. In addition, visibility, temperature and smoke spread measurement points are set at different spatial locations. The simulation results show that, the simulation results show that with the increase of roadway inclination, the inhibition effect of roadway mutation on flue gas spread decreases; the higher the intensity of the fire source, the higher the inhibition rate of the sudden change of roadway on the time of smoke spreading to the air inlet. However, the inhibition rate of the smoke to the air outlet time decreased. When the section length of the tunnel is 10 m and the distance from the fire source is 50 m, the effect of the section mutation on the smoke spread is the greatest.

Abstract Background Long-term excess exposure to environmental manganese (Mn) can lead to multi-system damage, especially in occupational populations. Therefore, we established a manganese-exposed workers healthy cohort (MEWHC), focusing on the systemic health effects related to Mn exposure. Here, we aimed to describe the follow-up activity for the MEWHC study and establish a standardized biological sample bank for the scientific management of high-quality biospecimens and the attached data from 2011 to 2017. Methods Baseline examinations for onsite workers were conducted, and the biobank for the MEWHC was first established in 2011; follow-up examinations occurred four times between July 2012 and November 2017. All questionnaires, clinical data and biological samples were routinely collected during each follow-up activity. Additional workers were recruited in 2016, which further enriched the resources of the biobank. Results A total of 2359 onsite workers and 612 retired workers at a ferromanganese refinery were enrolled in the prospective cohort, and their biological samples were obtained in the preliminary baseline survey and the follow-up investigation, including 2971 blood and urine samples from the cohort. In addition, 1524 hair samples, 1404 nail (toe and finger nails) and 1226 fecal samples were also collected. All specimens were preserved in the biobank, and the data were scientifically managed using a computer system. Conclusions The MEWHC study in China provides an effective way to obtain biological samples such as plasma, DNA, hair and urine for storage in a biobank for further study. The standardized management of various samples is crucial for accessing high-quality biospecimens.