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Abstract The occurrence of debris flow events in small-scale watersheds with dense vegetation in mountainous areas that result in significant loss of life and missing individuals challenges our understanding and expertise in investigating and preventing these disasters. This has raised concerns about the occurrence of large debris flow disasters from small watersheds. This study focused on a catastrophic debris flow that took place in Longtou Gully (0.45 km2) in Tianquan County, Ya’an City on 25 September 2021, which resulted in 14 deaths and missing individuals. Through comprehensive field investigations, high-precision remote sensing data analyses, and numerical simulations, we analyzed the triggering mechanisms and dynamic processes of this event. Our results indicate that the convergence hollow at the channel head exhibited higher hydraulic conditions during rainfall compared to gentle slopes and convex terrains, leading to the instability of colluvial soil due to the expansion of the saturated zone near the soil–bedrock interface. The entrainment of material eroded from the channel resulted in an approximately 4.7 times increase in volume, and the channel scarp with a height of about 200 m amplified the destructive power of the debris flow. We emphasize the need to take seriously the possibility of catastrophic debris flows in small-scale watersheds, with colluvial deposits in hollows at the channel head under vegetation cover that serve as precursor material sources, and the presence of channel scarps formed by changes in the incision rate of the main river, which is common in the small watershed on both sides. This study provides insights for risk assessment of debris flows in small-scale catchments with dense vegetation cover in mountainous areas, highlighting the importance of vigilance in addressing disasters in small-scale catchments, particularly in regions with increasing human–environment conflicts.

To study the microscopic structure, thermal and mechanical properties of sandstones under the influence of temperature, coal measure sandstones from Southwest China are adopted as the research object to carry out high-temperature tests at 25 °C–1000 °C. The microscopic images of sandstone after thermal treatment are obtained by means of polarizing microscopy and scanning electron microscopy (SEM). Based on thermogravimetric (TG) analysis and differential scanning calorimetric (DSC) analysis, the model function of coal measure sandstone is explored through thermal analysis kinetics (TAK) theory, and the kinetic parameters of thermal decomposition and the thermal decomposition reaction rate of rock are studied. Through the uniaxial compression experiments, the stress‒strain curves and strength characteristics of sandstone under the influence of temperature are obtained. The results show that the temperature has a significant effect on the microstructure, mineral composition and mechanical properties of sandstone. In particular, when the temperature exceeds 400 °C, the thermal fracture phenomenon of rock is obvious, the activity of activated molecules is significantly enhanced, and the kinetic phenomenon of the thermal decomposition reaction of rock appears rapidly. The mechanical properties of rock are weakened under the influence of rock thermal fracture and mineral thermal decomposition. These research results can provide a reference for the analysis of surrounding rock stability and the control of disasters caused by thermal damage in areas such as underground coal gasification (UCG) channels and rock masses subjected to mine fires.

The Yili Valley, located on the border between China and Kazakhstan, serves as the juncture of North and South Xinjiang, and stands as a pivotal outpost on the Silk Road Economic Belt. This area possesses a fragile ecological environment and experiences frequent debris flow disasters. In this study, four machine learning models:Random Forest (RF), Logistic Regression (LR), Support Vector Machine (SVM), and Decision Tree (DT)-- were employed to evaluate the debris flow susceptibility and compute the weights of evaluation factors. The models were fed inputs comprising 398 identified debris flow channels and 14 feature parameters such as fault density, topographic relief, land use, NDVI, multi-year average rainfall, etc obtained through remote sensing and field surveys. Also, the accuracy of the four machine learning models was evaluated by ROC curves and calculating the Area Under the Curve (AUC). The research results show that: (1) High debris flow susceptibility areas are mainly located in the Tianshan Mountains in the deep river valley region and the loess-covered areas in the mountain front slopes; (2) Multi-year average rainfall, drought index, and topographic relief variability are the top three influential factors controlling the spatial development of debris flows; (3) The AUC values for the validation datasets of the four models were 0.938 (RF), 0.932 (SVM), 0.89 (LR), 0.79 (DT), with the Random Forest model exhibiting superior predictive capability in assessing susceptibility in the region; (4) The disruption of ecological vegetation in the loess-covered region of the study area is a significant cause of frequent debris flow occurrences. Ecological governance and protection efforts should be emplasized to reduce soil erosion and effectively mitigate debris flow disasters at their source.

The regulation of immune functions and the maintenance of homeostasis in the internal environment are both integral to human gut microbiota (GM). If GM is disturbed, it can result in a range of autoimmune diseases, including chronic inflammatory skin conditions. Chronic inflammatory skin diseases driven by T or B-cell-mediated immune reactions are complex, including the most prevalent diseases and some rare diseases. Expanding knowledge of GM dysbiosis in chronic inflammatory skin diseases has emerged. The GM has some causal roles in the pathogenesis of these skin conditions. Targeting microbiota treatment, particularly fecal microbiota transplantation (FMT), is considered to be a promising strategy. FMT was commonly used in intestinal diseases by reshaping and balancing GM, serving as a reasonable administration in these skin inflammatory diseases. This paper summarizes the existing knowledge of GM dysbiosis in chronic inflammatory skin diseases and the research data on FMT treatment for such conditions.

The natural deep eutectic solvent (DES) was prepared by using betaine as hydrogen bond acceptor and organic acid, sugar group and alcohol group as hydrogen bond donor. Based on microwave-assisted extraction method, the extraction process of purple-fleshed potatoes anthocyanins (PPA) was optimized by single factor experiment combined with response surface analysis. The effects of microwave time, microwave power, solvent water content and solvent molar ratio on the extraction content of PPA were investigated. Moreover, the stability of PPA under different temperature and light conditions, and the free radical scavenging rates of DPPH, ABTS+ and OH were compared with conventional solvents to determine the antioxidant capacity in vitro. The results showed that the acidic deep eutectic solvent with betaine and citric acid (molar ratio of 1:2.1) and a water content of 28.6%, under the conditions of microwave power of 800 W and microwave time of 28 s, the extraction content of PPA could reach 228.658±1.241 mg/100 g, which was 56.92% higher than that of the conventional extraction process. In addition, the stability of PPA obtained by DES was significantly improved under different light and temperature conditions. The sunlight had the biggest effect on the PPA. The results showed that the preservation rate of PPA could reach more than 90% in the case of light avoidance, while the preservation rate of conventional solvent extraction was only 82.78%. Moreover, the content of anthocyanins would decrease continuously with the increase of temperature, and the preservation rate of both decreased significantly. Antioxidant capacity results demonstrated that the antioxidant capacity of PPA obtained from DES was stronger, and the values of IC50 for different radical scavenging capacity were less than the conventional solvent extraction. The IC50 values of DPPH radical scavenging capacity ranged from 45.95 μg/mL to 41.54 μg/mL, ABTS+ radical scavenging capacity IC50 values from 17.81 μg/mL to 11.30 μg/mL, OH radical scavenging capacity IC50 values from 162.00 μg/mL to 22.44 μg/mL. Therefore, the content, stability and antioxidant activity of PPA are closely related to the extraction solvent, and our extraction process provides a new idea for the utilization and development of purple-fleshed potatoes anthocyanins.

Abstract Permeability assessment of naturally fractured rocks and fractured rocks after fracturing is critical to the development of oil and gas resources. In this paper, based on the discrete fracture network (DFN) modeling method, the conventional discrete fracture network (C-DFN) and the rough discrete fracture network (R-DFN) models are established. Through the seepage numerical simulation of the fractured rocks under different DFN, the differences in permeability of the fractured rocks under different parameters and their parameter sensitivity are analyzed and discussed. The results show that unconnected and independent fractures in the fracture network may weaken the seepage capacity of the fractured rocks. The fractured rock permeability increases with increase in connectivity and porosity and decreases with increase in maximum branch length and fracture dip. The use of C-DFN to equate the fracture network in the fractured rocks may underestimate the connectivity of the fracture network. For the more realistic R-DFN, the promotion of gas flow by connectivity is dominant when connectivity is high, and the hindrance of gas flow by fracture roughness is dominant when connectivity is low or when it is a single fracture. The permeability of the fractured rocks with R-DFN is more sensitive to the parameters than that of the fractured rocks with C-DFN. The higher the connectivity and porosity of the fractured rocks, the more obvious the difference between the permeability of the fractured rocks evaluated by C-DFN and R-DFN.

Abstract Background While mean platelet volume (MPV) is linked to severity and all-cause mortality in patients with sepsis, its association with all-cause mortality and cardiovascular mortality in patients treated with peritoneal dialysis (PD) remains unknown. Objectives The purpose of this study was to estimate the relationship between MPV and all-cause mortality and cardiovascular mortality among patients treated with PD. Method We retrospectively collected 1322 patients treated with PD from November 1, 2005 to August 31, 2019. All-cause mortality and cardiovascular mortality was identified as the primary outcome. MPV was classified into three categories by means of X-tile software. The correlation between MPV and all-cause mortality was assessed by Cox model. Survival curves were performed by Kaplan-Meier method. Results The median follow-up period was 50 months (30–80 months), and a total of 360 deaths were recorded. With respect to all-cause mortality, patients in MVP ≥ 10.2 fL had considerably higher risk of all-cause mortality among three models (HR 0.68, 95%CI 0.56–0.84; HR 0.70, 95%CI 0.56–0.87; HR 0.73, 95%CI 0.59–0.91; respectively). Moreover, patients treated with PD, whose MVP ≥ 10.2 fL, also suffered from significantly higher risk of cardiovascular mortality in model 1, 2, and 3 (HR 0.63, 95%CI 0.46–0.85; HR 0.66, 95%CI 0.48–0.91; HR 0.69, 95%CI 0.50–0.95; respectively). Conclusions This study indicates that MPV is independently correlated with both all-cause mortality and cardiovascular mortality in PD.

Multi-cluster fracturing has emerged as an effective technique for enhancing the productivity of deep shale reservoirs. The presence of natural bedding planes in these reservoirs plays a significant role in shaping the evolution and development of multi-cluster hydraulic fractures. Therefore, conducting detailed research on the propagation mechanisms of multi-cluster hydraulic fractures in deep shale formations is crucial for optimizing reservoir transformation efficiency and achieving effective development outcomes. This study employs the finite discrete element method (FDEM) to construct a comprehensive three-dimensional simulation model of multi-cluster fracturing, considering the number of natural fractures present and the geo-mechanical characteristics of a target block. The propagation of hydraulic fractures is investigated in response to the number of natural fractures and the design of the multi-cluster fracturing operations. The simulation results show that, consistent with previous research on fracturing in shale oil and gas reservoirs, an increase in the number of fracturing clusters and natural fractures leads to a larger total area covered by artificial fractures and the development of more intricate fracture patterns. Furthermore, the present study highlights that an escalation in the number of fracturing clusters results in a notable reduction in the balanced expansion of the double wings of the main fracture within the reservoir. Instead, the effects of natural fractures, geo-stress, and other factors contribute to enhanced phenomena such as single-wing expansion, bifurcation, and the bending of different main fractures, facilitating the creation of complex artificial fracture networks. It is important to note that the presence of natural fractures can also significantly alter the failure mode of artificial fractures, potentially resulting in the formation of small opening shear fractures that necessitate careful evaluation of the overall renovation impact. Moreover, this study demonstrates that even in comparison to single-cluster fracturing, the presence of 40 natural main fractures in the region can lead to the development of multiple branching main fractures. This finding underscores the importance of considering natural fractures in deep reservoir fracturing operations. In conclusion, the findings of this study offer valuable insights for optimizing deep reservoir fracturing processes in scenarios where natural fractures play a vital role in shaping fracture development.

Deep reservoirs have a large difference in geo-stress, and compared to shallow reservoirs, multiple clusters of fracturing are usually required to effectively improve the quality of reservoir reconstruction. In this paper, considering the relevant geological parameters of a certain reservoir in the southwest, multi-cluster reservoir fracturing models under three-dimensional conditions based on the cohesive element modelling method are established. Then, the quantitative rules of fluid pressure, fracture length, fracture aperture, fracture area, tensile failure rate, and the fractal dimension of fracture morphology under different fracturing cluster numbers were revealed. The results show that compared to conventional fracturing, multi-cluster fracturing can significantly increase the number of main fractures and improve the effectiveness of reservoir reconstruction. As the number of clusters increases, the number of main fractures in the reservoir increases, but it can also lead to the increase of small opening fractures, which may be unfavourable for the pumping of proppant and subsequent mining. Meanwhile, based on the fractal dimension results of fracture morphology, it was found that under this simulation condition, the number of fracturing clusters had a significant impact on the fractal dimension of fracturing fractures before the fracturing of six clusters, while after the fracturing of six clusters, the impact of the number of fracturing clusters on the fractal dimension of fracturing fractures decreased. Therefore, when considering factors such as the complexity of fractures, multi-cluster fracturing does not necessarily result in more fracturing clusters being better but should be comprehensively considered for optimization. This study has certain reference significance for selecting the spacing between multiple fracturing clusters.

BackgroundMobile phones are becoming indispensable for life and have changed various aspects of people's lives. The psychological impacts of excessive mobile phone use have emerged as an impressive problem among college students. However, little is known about the associations of mobile phone addiction with suicide ideation and suicide attempt.MethodsA cross-sectional study was conducted with students from six universities in 2022. We collected the socio-demographic characteristics, suicide ideation, suicide attempt, psychosocial factors (depressive symptoms, social support, sleep quality), and health-related characteristics (smoking, drinking, body mass index). Mobile phone addiction was ascertained by the Mobile Phone Addiction Tendency Scale (MPATS). The associations of mobile phone addiction with suicide ideation and suicide attempt were estimated using binary logistic regression and restricted cubic splines regression.ResultsA total of 18,723 college students [6,531 males (34.9%) and 12,192 females (65.1%)] were included in the final analysis. Eleven percent of participants had a history of suicide ideation, and 1.8% of participants had engaged in suicide attempt. A total of 5,553 students (29.7%) met the criteria of mobile phone addiction (MPATS score ≥48), and the average score on the MPATS was 39.5 ± 13.0. After adjustment for potential covariates, mobile phone addiction was significantly associated with increased odds of suicide ideation (OR, 1.70; 95% CI, 1.53–1.88) and suicide attempt (OR, 1.48; 95% CI, 1.18–1.86). Gender did not affect the associations of mobile phone addiction with suicide ideation and suicide attempt (P for interaction > 0.05). The restricted cubic splines regression displayed a nonlinear dose-response association between MPATS score and risk of suicide ideation (P for non-linearity < 0.001), while a monotonically increasing risk of suicide attempt was found to be associated with an increasing MPATS score (P for non-linearity = 0.420).ConclusionsMobile phone addiction is associated with suicide ideation and suicide attempt among college students. The findings indicate that early examination, prevention, and intervention for mobile phone addiction may benefit the prevent and control of suicide.

With the depletion of conventional reservoir development, reservoir fracturing under deep high geo-stress and high geo-stress difference conditions is receiving increasing attention. Deep reservoirs typically require multi-cluster fracturing to achieve efficient reservoir transformation and development. In this paper, considering the relevant geological parameters of a certain reservoir in the southwest, three-dimensional multi-cluster reservoir fracturing models were established based on cohesive element modeling. Then, the propagation law of artificial fractures in reservoirs under the influence of the different number of fracturing clusters, injection displacement, and Young’s modulus in different regions of the 60 m fracturing well section is analyzed, and the quantitative law of parameters such as fracture length, maximum fracture width, injection point fracture width, fracture area, and tensile failure ratio during multi-cluster fracturing construction, as well as the propagation law of fracture morphology are revealed. The simulation results show that using multi-cluster fracturing can significantly improve the effectiveness of reservoir reconstruction, but as the number of fracturing clusters increases, it is also easy to form some small opening artificial fractures. These small opening artificial fractures may not be conducive to the transportation of proppants and fluids. During single cluster fracturing, the interface stiffness and rock Young’s modulus have a significant impact on the propagation of artificial fractures in the reservoir. As the number of fracturing clusters increases, the competition between artificial main fractures expands significantly, which may reduce the impact of interface stiffness and rock Young’s modulus. The fluid injection rate has a significant impact on reservoir fracturing, and in the same area, using high displacement injection can significantly increase the volume of reservoir reconstruction. This study can provide some reference for multi-cluster fracturing construction in deep reservoirs.

Anomaly detection is a crucial research field in computer vision with diverse applications in practical scenarios. The common anomaly detection methods employed currently consist of autoencoders, generative adversarial networks, and knowledge distillation (KD) models. However, the teacher and student models in KD might not always yield distinct representations to signify anomalies due to their similar model structure and data flow. This study proposes a novel autoencoder-like KD model based on the attention mechanism for anomaly detection. The pre-trained teacher model incorporates a dual attention module as the encoder, while the student model integrates the same dual attention module as the decoder. The teacher guides the student to learn the feature knowledge of the input image. To connect the teacher-student model, a BottleNeck module is employed, converting the features extracted from the teacher model into more compact latent codes for precise restoration by the student model, thereby achieving anomaly detection. In general, the proposed model exhibits superior performance compared to other existing anomaly detection models on specific datasets. Experimental results demonstrate that the proposed model attains the state-of-the-art (SOTA) performance in anomaly detection on the public dataset MVTec. It achieves an average AUC of 98.2% and 98.0% at sample and pixel levels, respectively.

Abstract Contour bevel gears have the advantages of high coincidence, low noise and large bearing capacity, which are widely used in automobile manufacturing, shipbuilding and construction machinery. However, when the surface quality is poor, the effective contact area between the gear mating surfaces decreases, affecting the stability of the fit and thus the transmission accuracy, so it is of great significance to optimize the surface quality of the contour bevel gear. This paper firstly analyzes the formation process of machined surface roughness of contour bevel gears on the basis of generating machining method, and dry milling experiments of contour bevel gears are conducted to analyze the effects of cutting speed and feed rate on the machined surface roughness and surface topography of the workpiece. Then, the surface defects on the machined surface of the workpiece are studied by SEM, and the causes of the surface defects are analyzed by EDS. After that, XRD is used to compare the microscopic grains of the machined surface and the substrate material for diffraction peak analysis, and the effect of cutting parameters on the microhardness of the workpiece machined surface is investigated by work hardening experiment. The research results are of great significance for improving the machining accuracy of contour bevel gears, reducing friction losses and improving transmission efficiency.

BackgroundNonsuicidal self-injury (NSSI) is a serious public health problem. The role of adverse childhood experiences (ACEs) and lifestyle on the risk for NSSI is still underexplored, especially among college students. We aimed to investigate the association of ACEs with the risk of NSSI, and effect modifications by lifestyle among college students.MethodsA total of 18,723 college students from six universities were recruited through a multistage, random cluster sampling method in Shaanxi province, China. The Adverse Childhood Experiences International Questionnaire was used to assess ACEs for each participant, and the Chinese version of the Ottawa Self-injury Inventory was used to assess the presence or absence of NSSI behaviors. Information about lifestyle was collected by a self-designed questionnaire. The associations of NSSI with ACEs and lifestyle were analyzed using logistic regression models. Furthermore, we constructed a combination score of multiple lifestyles and evaluated whether lifestyle modified the effect of ACEs on the risk of NSSI.ResultsThe prevalence of NSSI for the past 1 month, 6 months, and 12 months was 3.8, 5.3, and 6.5%, respectively. 82.6% of participants have reported experiencing at least one type of ACEs, and participants with higher levels of ACEs (≥4) were more likely to have higher odds of developing NSSI during the past 1 month (OR, 4.10; 95%CI, 3.38–4.97), 6 months (OR, 4.76; 95%CI, 4.03–5.62), and 12 months (OR, 5.62; 95%CI, 4.83–6.55), as compared with participants with low levels of ACEs (0–1). There were additive interactions between ACEs and lifestyle. Compared with participants with low levels of ACEs and healthy lifestyle, participants with high levels of ACEs and unhealthy lifestyle had the highest odds of NSSI during the past 1 month (OR, 5.56; 95%CI, 3.80–8.31), 6 months (OR, 6.62; 95%CI, 4.73–9.42), and 12 months (OR, 7.62; 95%CI, 5.59–10.52).ConclusionThese results suggest that ACEs play an important role in the occurrence of NSSI among college students, especially in those with unhealthy lifestyle. Our findings may help develop targeted intervention strategies for the prevention of NSSI.

Background: Arterial stiffness is an important indicator of cardiovascular aging. However, studies assessing the association between metal exposure and arterial stiffness are limited. Objective: The aim of this study was to investigate the independent and joint associations of metal exposure with arterial stiffness. Methods: This cross-sectional study recruited 2982 Chinese adults from August 2018 to March 2019 in Wuhan, China. The concentrations of 20 urinary metals were determined using inductively coupled plasma mass spectrometer. Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV). We used generalized linear model (GLM) to estimate the association of single metal exposure with baPWV. We used weighted quantile sum (WQS) regression to estimate the association of metal mixture with baPWV. Results: In GLM regression analysis, each doubling of urinary copper (Cu) and chromium (Cr) concentrations were associated with 6.48 (95 % CI: 2.51–10.45) cm/s and 3.78 (95 % CI: 0.42–7.14) cm/s increase in baPWV, respectively. In WQS regression analysis, each unit increase in WQS index of the metal mixture was associated with a 9.10 (95 % CI: 2.39–15.82) cm/s increase in baPWV. Cu, Zn, and Cr were the dominant urinary metals associated with baPWV. Conclusion: Metal exposure, both individually and in mixture, was associated with an increased risk of arterial stiffness. Our findings may provide a target for preventative strategies against cardiovascular aging.

The Tien Shan Mountain range connects Central Asia with northwestern China and is a crucial transport junction between East and West Asia. It is a common location for regional debris flows, which pose a significant risk to ecological security and the safety of people and property. Nevertheless, limited knowledge exists about the distribution of disaster risks and the impacted populations. This study uses advanced machine learning techniques to identify the key natural and social factors influencing these hazards and incorporates the Social Vulnerability Index (SoVI) to assess societal vulnerability. The outcomes demonstrate that (1) the debris flow hazard in the Tien Shan Mountain area is primarily governed by the geological structure, which dictates the material source and, in turn, dictates the onset of debris flows. (2) The vulnerability demonstrates a high spatial tendency in the north and a low one in the south, with evident spatial clustering characteristics. (3) A total of 19.13% of the study area is classified as high-hazard, with specific distribution zones including the northern foothills of the Tien Shan Mountains, the low-mountain zones of the southern foothills of the Tien Shan Mountains, and the Yili Valley zone. This holistic approach offers valuable insights into the spatial distribution of risks, aiding in prioritizing disaster preparedness and mitigation efforts. Also, our findings and conclusions are beneficial for local decision makers to allocate resources effectively and promote sustainable development practices in the region.

Abstract Aims Body roundness index (BRI) is an obesity‐related anthropometric index that combines waist circumference and height to better reflect body fat. This study aims to prospectively explore the relationship between BRI and the risk of heart failure (HF) based on a community‐based cohort. Methods and results A total of 140 362 individuals without tumour and HF at baseline were included from the Kailuan cohort study. Their demographic information, anthropometric parameters, and biochemical indexes were collected or measured. The participants were followed up until 31 December 2016 or death or diagnosed with HF, whichever came first. Cox proportional hazards model was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident HF. Restricted cubic spline analysis was applied to further evaluate the possible non‐linear dose–response relationship between BRI and the risk of HF. After a median follow‐up period of 9.84 years, we identified 1990 HF events. The participants were grouped into four groups according to the quartiles of BRI (Q1: ≤2.93, Q2: 2.93–3.59, Q3: 3.59–4.38, and Q4: ≥4.38). After adjustment for potential confounders, compared with the group of participants in the lowest quartile of BRI, the adjusted HRs (95%CI) were 1.03 (95%CI: 0.87–1.22), 1.27 (95%CI: 1.07–1.49), and 1.50 (95%CI: 1.26–1.78) for subjects in the Q2, Q3, and Q4 groups, respectively. With each standard deviation (here is 1.10) of BRI increasing, the risk of HF increased by 18% (HR: 1.18, 95%CI: 1.12–1.24). Subgroup analysis indicated that the association between BRI and HF was more prominent in younger people (HR: 2.94, 95%CI: 1.80–4.80) than older (HR: 1.89, 95%CI: 1.57–2.27) (P for interaction

Background: Klotho is widely recognized as a protein that combats aging and possesses antioxidative characteristics, which have been implicated in the pathophysiology of numerous diseases. There is emerging evidence suggesting that the consumption of dietary nutrients, particularly those rich in antioxidants, could be associated with serum Klotho concentrations. Dietary vitamin C is one of the critical nutrients that possesses antioxidant properties. Nonetheless, the association between dietary vitamin C consumption and serum Klotho concentrations remains unclear. Objective: Aiming to evaluate the relationship between serum Klotho concentrations and dietary vitamin C consumption among Americans aged 40 to 79, we conducted a population-based study. Methods: From the National Health and Nutrition Examination Survey (NHANES) conducted between 2007 and 2016, a grand total of 11,282 individuals who met the criteria were selected as eligible participants for the study. Serum Klotho concentrations were measured using an ELISA kit that is commercially available. Trained interviewers evaluated the consumption of dietary vitamin C in the diet through a 24-hour dietary recall technique. A generalized linear model was used to evaluate the correlation between the consumption of dietary vitamin C in the diet and serum Klotho concentrations. Further examination was conducted using restricted cubic spline (RCS) analysis to explore the non-linear correlation between dietary vitamin C consumption in the diet and serum Klotho concentrations. Results: After accounting for possible confounding factors, serum Klotho concentrations rose by 1.17% (95% confidence interval (CI): 0.37%, 1.99%) with every standard deviation (SD) rise in dietary vitamin C consumption. With the first quintile of dietary vitamin C consumption as a reference, the percentage change of serum Klotho concentrations in the fifth quintile of dietary vitamin C consumption was 3.66% higher (95% CI: 1.05%, 6.32%). In older, normal-weight, and male participants, the subgroup analysis revealed a stronger correlation between dietary vitamin C consumption and serum Klotho concentrations. Analysis of RCS showed a linear positive association between dietary vitamin C consumption and the levels of serum Klotho concentrations. Conclusion: The findings of this research indicate a strong and positive correlation between dietary vitamin C consumption and serum Klotho concentrations among the general adult population in the United States. Further studies are needed to validate the present findings and to explore specific mechanisms.

Background: The relationship between dietary carbohydrate intake and serum Klotho levels, an aging biomarker, remains uncertain. Objective: This study aimed to investigate the association between dietary carbohydrate intake and serum Klotho levels among American adults aged 40–79. Methods: We analyzed data from 10,669 adults aged 40–79 years who participated in the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2016. Trained interviewers assessed dietary carbohydrate intake using a 24 h dietary recall. Serum Klotho concentrations were measured using commercially available ELISA kits provided by IBL International, Japan, which served as the study outcome. Generalized linear models were used to assess the relationship between the carbohydrate energy percentage and serum Klotho concentration, and restricted cubic spline (RCS) analysis was employed to explore any nonlinear associations. Results: After adjusting for multiple variables, we observed a nonlinear inverse J-shaped relationship (p for non-linearity < 0.001) between the carbohydrate energy percentage and serum Klotho levels. Specifically, the highest serum Klotho levels were associated with a total carbohydrate energy percentage ranging from 48.92% to 56.20% (third quartile). When the carbohydrate energy percentage was evaluated in quartiles, serum Klotho levels decreased by 5.37% (95% CI: −7.43%, −3.26%), 2.70% (95% CI: −4.51%, −0.86%), and 2.76% (95% CI: −4.86%, −0.62%) in the first quartile (

Abstract Aims Previous studies suggested an adverse association between higher fasting blood glucose (FBG) variability and cardiovascular disease (CVD). Lifetime risk provides an absolute risk assessment during the remainder of an individual’s life. However, the association between FBG variability and the lifetime risk of CVD is uncertain. Objective We aimed to investigate the effect of the visit-to-visit FBG variability on the lifetime risk of CVD. Methods This study included participants from the Kailuan Study who did not have CVD at index ages 35, 45, and 55 years. The FBG variability was defined as the coefficient of variation (CV) of three FBG values that were measured during the examination periods of 2006–2007, 2008–2009, and 2010–2011. We used a modified Kaplan-Merrier method to estimate lifetime risk of CVD according to tertiles of FBG variability. Results At index age 35 years, the study sample comprised 46,018 participants. During a median follow-up of 7.0 years, 1889 participants developed CVD events. For index age 35 years, participants with high FBG variability had higher lifetime risk of CVD (32.5%; 95% confidence interval [CI]: 28.9–36.1%), compared with intermediate (28.3%; 95% CI: 25.5 –31.1%) and low (26.3%; 95% CI: 23.0–29.5%) FBG variability. We found that higher FBG variability was associated with increased lifetime risk of CVD in men but not women. Similar patterns were observed at index ages 45 and 55 years. Conclusions Higher FBG variability was associated with increased lifetime risk of CVD at each index age. Focusing on the FBG variability may provide an insight to the clinical utility for reducing the lifetime risk of CVD.

Background: Klotho is an aging-related marker closely associated with a number of diseases. A growing body of evidence suggests that dietary factors and lifestyle habits can impact serum Klotho levels. The effect of dietary fiber, a key component of a healthy diet, on the body’s serum Klotho levels has not been fully elucidated. Objective: The aim of this study was to explore the relationship between dietary fiber intake and serum Klotho levels in people aged 40–79 years in the United States. Methods: A total of 11,282 participants were included in this study, all from the National Health and Nutrition Examination Survey from 2007 to 2016. Dietary fiber intake was assessed by uniformly trained interviewers using the 24 h dietary recall method. Serum Klotho was quantified using commercially available ELISA kits manufactured by IBL International, Japan. The relationship between dietary fiber intake and serum Klotho levels was analyzed using a multiple linear regression model. Subsequently, the non-linear dose–response relationship between the two was further explored using a restricted cubic spline (RCS) model. Results: After adjusting for potential confounders, serum Klotho levels increased by 1.9% (95% confidence interval [CI]: 0.8%, 3.0%) for each interquartile range increase in dietary fiber intake in all participants. Considering dietary fiber intake as a categorical variable, serum Klotho levels were found to be 4.7% higher in participants in the highest quartile of dietary fiber intake than in those in the lowest quartile (95% CI: 1.8%, 7.6%). RCS plots depicted a non-linear positive correlation between dietary fiber intake and serum Klotho levels. Subgroup analysis revealed that the relationship between dietary fiber intake and serum Klotho levels was more pronounced in older (percentage change: 7.0%; 95% CI: 2.5%, 11.7%) and overweight and obese participants (percentage change: 4.9%; 95% CI: 1.5%, 8.4%). Conclusions: The results of this study showed that dietary fiber intake was significantly associated with serum Klotho levels in participants. This finding is yet to be further confirmed by prospective studies.

Abstract Background Triglyceride–glucose (TyG) index, a simple surrogate marker of insulin resistance, has been reported to be associated with arterial stiffness. However, previous studies were limited by the cross-sectional design. The purpose of this study was to explore the longitudinal association between TyG index and progression of arterial stiffness. Methods A total of 6028 participants were derived from the Kailuan study. TyG index was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. Arterial stiffness was measured using brachial-ankle pulse wave velocity (baPWV). Arterial stiffness progression was assessed by the annual growth rate of repeatedly measured baPWV. Multivariate linear regression models were used to estimate the cross-sectional association of TyG index with baPWV, and Cox proportional hazard models were used to investigate the longitudinal association between TyG index and the risk of arterial stiffness. Results Multivariate linear regression analyses showed that each one unit increase in the TyG index was associated with a 39 cm/s increment (95%CI, 29–48 cm/s, P

Herein, the effect of the background magnetic field on plasma characteristics in a Hall thruster is numerically investigated using DUT-HTFS [Li et al., AIP Adv. 12, 015117 (2022)], an integrated fluid simulation platform on Hall thruster plasmas. The research shows that the background magnetic field significantly influences the distribution of the plasma density, especially the radial profiles of the plasma density near the ionization region and the acceleration region. In addition, the positions of the peak values of the electron power absorptions mainly occur near the dielectric walls of the exhaust plane, and the electron power absorption mechanism is mainly dominated by the Ohmic heating. The peak values of the axial electron current density on the inner and outer dielectric walls are higher than that on the centerline. This phenomenon is closely related to the near wall conduction mechanism of the electrons. In addition, the background magnetic field significantly influences the shapes, positions, and magnitudes of the peak values of the plasma parameters, such as the plasma density, the electron current density, the axial electric field, the electric potential, and the ionization rate. These results will help us to provide a valuable reference and reduce the risk for the experimental test programs and the applications of Hall thrusters in the future.

Superalloys are widely used in the aerospace field and are a typical difficult-to-cut material. When the PCBN tool is used to cut superalloys, there will be problems such as a large cutting force, a high cutting temperature, and gradual tool wear. High-pressure cooling technology can effectively solve these problems. Therefore, this paper carried out an experimental study of a PCBN tool cutting superalloys under high-pressure cooling and analyzed the influence of high-pressure coolant on the characteristics of the cutting layer. The results show that the main cutting force can be reduced by 19~45% and 11~39% when cutting superalloys under high-pressure cooling compared with dry cutting and atmospheric pressure cutting, respectively, in the range of test parameters. The surface roughness of the machined workpiece is less affected by the high-pressure coolant, but the high-pressure coolant can help reduce the surface residual stress. The high-pressure coolant can effectively improve the chip’s breaking ability. In order to ensure the service life of PCBN tools, when cutting superalloys under high-pressure cooling the coolant pressure should not be too high, and 50 bar is more appropriate. This provides a certain technical basis for the efficient cutting of superalloys under high-pressure cooling conditions.

Since the flank has an important influence on the surface of a workpiece, and as microstructure flaws of the surface metamorphic layer are a key factor that affects the service performance of a part, this work studied the influence of flank wear on the microstructure characteristics of the metamorphic layer under the conditions of high-pressure cooling. First, Third Wave AdvantEdge was used to create a simulation model of cutting GH4169 using tools with different flank wears under high-pressure cooling. The simulation findings emphasized the impact of flank wear width (VB) on the cutting force, cutting temperature, plastic strain, and strain rate. Second, an experimental platform was established for cutting GH4169 under high-pressure cooling, and the cutting force during the machining process was recorded in real time and compared with the simulation results. Finally, an optical microscope was used to observe the metallographic structure of the GH4169 workpiece section. The microstructure characteristics of the workpiece were analyzed using a scanning electron microscope (SEM) and electron backscattered diffraction (EBSD). It was discovered that, as the flank wear width increased, so did the cutting force, cutting temperature, plastic strain, strain rate, and plastic deformation depth. The relative error between the simulation results of the cutting force and the experimental results was within 15%. At the same time, near the surface of the workpiece, there was a metamorphic layer with fuzzy grain boundaries and refined grain. With an increase in flank wear width, the thickness of the metamorphic layer increased from 4.5 μm to 8.7 μm and the grain refinement intensified. The high strain rate promoted recrystallization, which caused an increase in the average grain boundary misorientation and high-angle grain boundaries, as well as a reduction in twin boundaries.

In the current international situation, energy storage is an important means for countries to stabilize their energy supply, of which underground storage of natural gas is an important part. Depleted gas reservoir type underground gas storage (UGS) has become the key type of gas storage to be built by virtue of safety and environmental protection and low cost. The multi-cycle high injection and production rate of natural gas in the depleted gas reservoir type UGS will cause the in-situ stress disturbance. The slip risk of fault in the geological system increases greatly compared with that before the construction of the storage engineering, which becomes a great threat to the sealing of the gas storage. Reasonable injection and production strategy depend on the reliable assessment of the shear behavior of the fault belt, which can guarantee the sealing characteristics of the UGS geological system and the efficient operation of the UGS. Therefore, the shear behavior of the fault is studied by carrying out experiments, which can provide important parameters for the evaluation of fault stability. However, there is a large gap between the rock samples used in the previous experimental study and the natural faults, and it is difficult to reflect the shear failure characteristics of natural faults. In this paper, similar fault models based on high-precision three-dimensional scanners and engraving machines, filled with three types of fault gouge, are prepared for a batch of representative direct shear tests. The results show that the peak shear strength of the fault rocks with a shear surface is higher than that of the fault rocks with a tensile surface. Compared with the clay mineral content, the roughness of the fault surface is much more significant for the shear strength of the fault rock. For the fault rocks with similar fault surface morphology, the higher the clay content in the fault gouge, the greater the shear strength of the fault rocks. For the fault rocks with different fault surface morphology and the same fault gouge, the cohesion and internal friction angle of the tensile type is generally smaller than that of the shear type.

Background: Pregnancy leads to substantial maternal metabolic and lifestyle alterations. However, it is still unclear whether repeated exposure to these changes will influence the development of gestational diabetes mellitus (GDM). In the present study, we aimed to investigate the association between the number of pregnancies and GDM among Chinese women. Methods: A total of 7,008 subjects from the Healthy Baby Cohort study were included in this study. The number of pregnancies was classified into three categories: 1, 2, or ≥3 pregnancies. GDM was diagnosed using International Association of Diabetes and Pregnancy Study Groups criteria. Multivariate logistic regression models were used. Results: In the fully adjusted model, women with ≥3 pregnancies had a 1.27-fold (95% confidence interval [CI], 1.05–1.54) higher risk of GDM. Among women ≥30 years old, 2 and ≥3 pregnancies were associated with a higher risk of GDM (odds ratio [OR] 1.32; 95% CI, 1.01–1.73 and OR 1.54; 95% CI, 1.17–2.01, respectively). Among women with a pre-pregnancy BMI

In this work, a newly integrated fluid simulation platform, named DUT-HTFS, is developed for the multiple physical fields in Hall thrusters. The integrated simulation platform includes three inter-related parts: the geometry module, background magnetic field module, and plasma module. Using the geometry module, three sets of meshes for a Hall thruster are obtained. One set of the mesh is for the calculation of the background magnetic fields, the second is for the electric potentials, and the third is for the plasmas. Based on the meshes and using the background magnetic field module, a numerical result of the background magnetic field in the Hall thruster is obtained and discussed. Based on the meshes and the numerical result of the background magnetic field, using the plasma module, the numerical results of the plasmas in the Hall thruster are obtained. The results of the plasma density, the electric field, the electric potential, and the ionization rate are similar to those from HPHALL (Hybrid-PIC Hall thruster code) simulations and are qualitatively consistent with the experimental results from the literature. Furthermore, varying the neutral gas pressure from 0.02 to 0.03 Torr, the numerical results of the plasmas in the Hall thruster are obtained. These results reveal that neutral gas pressure effects contributed considerably to the shape, location, and magnitude of the peak plasma properties, including the ion density, axial electric field, and ionization rate. This fluid simulation platform could provide a new angle of view for better understanding of the physical mechanism in Hall thrusters.

The memristor-based neural network configuration is a promising approach to realizing artificial neural networks (ANNs) at the hardware level. The memristors can effectively simulate the strength of synaptic connections between neurons in neural networks due to their diverse significant characteristics such as nonvolatility, nanoscale dimensions, and variable conductance. This work presents a new synaptic circuit based on memristors and Complementary Metal Oxide Semiconductor(CMOS), which can realize the adjustment of positive, negative, and zero synaptic weights using only one control signal. The relationship between synaptic weights and the duration of control signals is also explained in detail. Accordingly, Widrow–Hoff algorithm-based memristive neural network (MNN) circuits are proposed to solve the recognition of three types of character pictures. The functionality of the proposed configurations is verified using SPICE simulation.

High temperature and strain will occur in the cutting area during dry milling of contour bevel gears, which causes plastic deformation of the workpiece, resulting in changes in the physical properties of the machined surface’s metamorphic layer, reducing the quality of the workpiece’s machined surface. Therefore, it is necessary to investigate the properties of the metamorphic layer and the work hardening behavior of the machined surfaces of contour bevel gears. The paper first establishes a single-tooth finite element simulation model for a contour bevel gear and extracts the temperature field, strain field and strain rate at different depths from the machined surface. Then, based on the simulation results, the experiment of milling contour bevel gears is carried out, the microscopic properties of the machined metamorphic layer are studied using XRD diffractometer and ultra-deep field microscopy, and the work hardening behavior of the machined metamorphic layer under different cutting parameters is studied. Finally, the influence of the cutting parameters on the thickness of the metamorphic layer of the machined surface is investigated by scanning electron microscopy. The research results can not only improve the surface quality and machinability of the workpiece, but are also significant for increasing the fatigue strength of the workpiece.

Background: Prenatal exposure to thallium is related to adverse birth outcomes. However, little is known about the effects of prenatal exposure to thallium on the mitochondrial DNA copy number (mtDNAcn) in newborns; such knowledge might reveal a potential mechanism linking maternal thallium exposure and adverse birth outcomes. Objective: To investigate the trimester-specific associations of maternal thallium exposure with cord blood leukocyte mtDNAcn. Methods: A total of 746 pregnant women with trimester-specific urinary samples and cord blood samples were recruited from Wuhan Children Hospital between November 2013 and March 2015 in Wuhan City, China. The concentration of thallium in maternal urine was quantified using inductively coupled plasma mass spectrometry (ICP-MS). Cord blood leukocyte mtDNAcn was measured by real-time quantitative polymerase chain reaction (qPCR). Trimester-specific associations of specific gravity (SG)–adjusted urinary thallium concentrations with mtDNAcn were estimated using a multiple informant model. Results: The geometric mean value of maternal urinary thallium was 0.34 μg/L, 0.36 μg/L, and 0.34 μg/L for the first, second, and third trimesters, respectively. Prenatal exposure to thallium during the first trimester, rather than during the second or the third trimester, was identified as negatively related to mtDNAcn. The multiple informant model showed a 10.4% lower level of mtDNAcn with each doubling increase of thallium levels (95% CI, −16.4%, −3.9%; P = 0.002). The observed associations were stronger among female newborns and among newborns born to older mothers. Conclusions: The present study revealed a significant negative association between maternal thallium exposure during early pregnancy and cord blood leukocyte mtDNAcn in Chinese newborns, pointing to the important role of mitochondria as a target of thallium toxicity in early pregnancy. Keywords: Thallium, Mitochondrial DNA copy number, Early pregnancy, Cohort study

Background: Telomere length (TL) is considered as a surrogate of biological aging and has been related to aging-related diseases. The initial setting of newborn TL has important implications for telomere dynamics in adulthood, and is affected by the intrauterine environment. However, the effects of prenatal air pollution exposure on the initial setting of newborn TL are poor understood. Objectives: We aimed to explore the trimester-specific relationships between maternal air pollution exposure and newborn TL. Methods: Between November 2013 and March 2015, a total of 762 mother-newborn pairs were recruited in a birth cohort study in Wuhan, China. Relative cord blood TL was assessed using quantitative real-time polymerase chain reaction. Maternal exposures to PM2.5, PM10, SO2, CO, and NO2, were determined using spatial-temporal land use regression models. Multiple informant models were applied to explore the trimester-specific associations of maternal air pollution exposure with cord blood TL. Results: In single-pollutant models, a 10 μg/m3 increase in PM2.5, PM10, SO2, and a 100 μg/m3 increase in CO during the third trimester were related to 3.71% (95% confidence interval [CI]: −6.06%, −1.30%), 3.24% (95% CI: −5.29%, −1.14%), 11.07% (95% CI: −18.86%, −2.53%), and 3.67% (95% CI: −6.27%, −1.00%) shorter cord blood TL, respectively. The inverse relationships between exposures to PM2.5, PM10, SO2, and CO during the third trimester and cord blood TL were more evident in male infants. In multi-pollutant models, exposures to PM2.5 and PM10 during the third trimester were both related to shorter cord blood TL, but not SO2 and CO. Conclusion: This study suggested that maternal exposures to PM2.5, PM10, CO, and SO2 during the third trimester were related to shorter newborn TL, which highlights the importance of improving air quality in favor of subsequent health in later life of newborns. Keywords: Air pollution, Telomere length, Maternal exposure, Newborns, trimester-specific

Abstract Background Newborn telomere length (TL) is considered a potential marker for future disease and lifelong health, but few epidemiological studies have examined the determinants of TL in early life. The study aim was to investigate whether there is an association between prenatal cadmium exposure and relative cord blood TL in Chinese newborns. Methods Participants were 410 mother–newborn pairs drawn from a prospective birth cohort study conducted in Wuhan, China, between November 2013 and March 2015. Urine samples were collected from pregnant women during their period of institutional delivery. Urinary cadmium concentrations were measured by inductively coupled plasma mass spectrometry. The real-time quantitative polymerase chain reaction detection was used to measure relative TL using genomic DNA isolated from umbilical cord blood leukocytes. Multivariate linear regression models were used to estimate the effect of prenatal urinary cadmium concentration on relative cord blood TL. Results The geometric mean of maternal urinary cadmium concentration was 0.68 μg/g creatinine. In the multivariate-adjusted linear regression model, per doubling of maternal urinary cadmium concentration was associated with 6.83% (95% CI − 11.44%, − 1.97%; P = 0.006) shorter relative cord blood TL. Stratified analyses indicated that the inverse association between prenatal urinary cadmium and newborn relative TL was more pronounced among female infants and mothers

Objective: Telomere length (TL) is a biomarker for biological aging, and the initial setting of TL at birth is a determinant factor of TL in later life. Newborn TL is sensitive to maternal metals concentrations, while study about the association between maternal manganese (Mn) concentrations and newborn TL was not found. Our study aimed to investigate whether newborn TL is related to maternal Mn concentrations. Methods: Data were collected from a birth cohort study of 762 mother-newborn pairs conducted from November 2013 to March 2015 in Wuhan, China. We measured the Mn concentrations in spot urine samples collected during three trimesters by inductively coupled plasma mass spectrometry (ICP-MS) and relative cord blood TL by quantitative real-time polymerase chain reaction (qPCR). We applied multiple informant models to investigate the associations between maternal Mn concentrations and cord blood TL. Results: The geometric mean of creatinine-corrected urinary Mn concentrations were 1.58 μg/g creatinine, 2.53 μg/g creatinine, and 2.62 μg/g creatinine in the first, second, and third trimester, respectively. After adjusting for potential confounders, a doubling of maternal urinary Mn concentration during the second trimester was related to a 2.10% (95% CI: 0.25%, 3.99%) increase in cord blood TL. Mothers with the highest tertile of urinary Mn concentrations during the second trimester had a 9.67% (95% CI: 2.13%, 17.78%) longer cord blood TL than those with the lowest tertile. This association was more evident in male infants. No relationship was found between maternal urinary Mn concentrations and cord blood TL during the first and third trimesters in our study. Conclusions: Our findings suggested that maternal Mn concentration during the second trimester was positively associated with newborn TL. These results might provide an epidemiology evidence on the protective role of maternal Mn for newborn TL and offer clues for the early prevention of telomere shortening related diseases.

Background: Rare earth elements (REE) have been widely used in industry and agriculture. Mitochondria are susceptible to environmental exposure and the change of mitochondrial DNA (mtDNA) content is a proxy indicator of mitochondrial response to damage. However, no study has explored the associations between prenatal repeated REE exposure and newborn mtDNA content. Objectives: We aimed to investigate the trimester-specific associations between prenatal REE exposure and newborn mtDNA content. Methods: A total of 587 mother-newborn pairs were recruited from Wuhan Children’s Hospital between November 2013 and March 2015 in Wuhan, China. Urinary concentrations of REE collected during 3 trimesters were measured by inductively coupled plasma mass spectrometry (ICP-MS). Quantitative real-time polymerase chain reaction (qPCR) was used to measure relative cord blood mtDNA content. We evaluated the trimester-specific associations between prenatal REE exposure and relative cord blood mtDNA content with multiple informant models. False discovery rate (FDR) was used to correct for multiple testing. Results: After adjustment for potential confounders, prenatal exposure to REE [gadolinium (Gd), dysprosium (Dy), erbium (Er), praseodymium (Pr)] during the third trimester were positively related to cord blood mtDNA content, and the positive associations with cord blood mtDNA content were still observed in Dy, Er, and Pr after FDR correction. Conclusions: This prospective study demonstrated that maternal REE exposure during the third trimester was associated with the increased newborn mtDNA content, and the third trimester might be a potential window for sensitivity of newborn mtDNA content to REE exposure. The results might provide evidence of the potential health effects of environmental REE exposure.

Background: Prior studies have suggested exposure to heavy metals and endocrine disrupting chemicals could disturb the homeostasis of thyroid stimulating hormone (TSH), but no epidemiology study concerning the influence of rare earth elements (REE) exposure during pregnancy on neonatal TSH levels. The present study aimed to investigate the relationships between prenatal REE exposure and neonatal TSH levels. Methods: A total of 7367 pregnant women were recruited from Wuhan Children’s Hospital between September 2012 and October 2014 in Wuhan, China. Urinary concentrations of cerium (Ce), and ytterbium (Yb) were measured by inductively coupled plasma mass spectrometry (ICP-MS). Immunofluorescence assay was used to detect neonatal TSH levels. The associations between REE exposure and neonatal TSH levels were evaluated using multivariate linear regression models. Results: The geometric means of maternal urinary Ce and Yb concentrations were 0.060 μg/g creatinine and 0.025 μg/g creatinine, respectively. The results showed that per doubling of maternal urinary Ce and Yb were associated with 4.07% (95% CI: −5.80%, −2.31%), 5.13% (95% CI: −6.93%, −3.30%) decreased neonatal TSH levels respectively in the adjusted model. Sex stratified analysis demonstrated that the decreased neonatal TSH levels were observed both in male infants and female infants, and the decrease was greater in male infants in urinary Ce. There were no significant interactions between maternal urinary Ce, Yb and infant sex (Ce: P for interaction = 0.173, Yb: P for interaction = 0.967). Conclusions: Our findings demonstrated that increased maternal urinary Ce and Yb were associated with decreased neonatal TSH levels. Further researches from different populations are warranted to verify the association and to explore the mechanisms. Keywords: Rare earth elements, Thyroid-stimulating hormone, Newborns, Pregnancy

Salt stress is one of the abiotic factors that causes adverse effects in plants and there is an urgent need to detect salt stress in plants as early as possible. Multicolor fluorescence imaging, as a powerful tool in plant phenotyping, can provide information about primary and secondary metabolism in plants to detect the responses of the plants exposed to stress in the early stage. The purpose of this study was to evaluate the potential of multicolor fluorescence imaging’s application in the early detection of salt stress in plants. In this study, the measurements were conducted on Arabidopsis and the multicolor fluorescence images were acquired at 440, 520, 690, and 740 nm with a self-developed imaging system consisting of a UV light-emitting diode (LED) panel for an excitation at 365 nm, a charge coupled device (CCD) camera, interference filters, and a computer. We developed a classification method using the imaging analysis of multicolor fluorescence based on principal component analysis (PCA) and a support vector machine (SVM). The results showed that the four principal fluorescence feature combinations were the ideal indicators as the inputs of the SVM model, and the classification accuracies of the control and salt-stress treatment at 5 days and 9 days were 92.65% and 98.53%, respectively. The results indicated that multicolor fluorescence imaging combined with PCA and SVM could act as a tool for early detection in salt-stressed plants.

The nickel-based superalloy is widely used in aerospace. It is a typical difficult-to-cut material with poor plasticity. During the cutting process, the fluctuation of the cutting force caused by the change of cutting conditions can aggravate tool vibration, thereby reducing the surface quality of the machined workpiece. However, the emergence of high-pressure cooling technology provides technical support for overcoming the difficulty in superalloy processing. Therefore, it is of great significance to optimize the tool vibration and surface roughness of cutting GH4169 under high-pressure cooling. Taking GH4169 as the research object, the single-factor and orthogonal high-pressure cooling cutting experiments were conducted firstly in this paper. Then, the methods of the main effect diagram and response surface were applied to analyze the impact of cutting speed, feed rate, cutting depth, and cooling pressure on the three-way tool vibration. Next, MATLAB was adopted to draw the frequency spectrum of radial tool vibration at different cutting speeds, and the relationship between chip morphology, tool vibration, and workpiece surface roughness at different cutting speeds was discussed. Based on this, a mathematical model of radial tool cutting vibration and surface roughness related to the cutting amount and cooling pressure was established. Support vector machine (SVM) was applied to make predictions. Meanwhile, the non-dominated sorting genetic algorithm with an elitist strategy was adopted for multi-objective optimization, and the optimization results were verified through experiments. The results indicated that the feed rate and cutting depth had a great impact on the tool vibration and surface roughness. The established mathematical model was accurate and effective for optimizing the cutting parameters. These results are of great significance to improve the cutting stability and the quality of machined surface.

A joint multiuser detection (MUD) scheme for wireless sensor networks (WSNs) is proposed to suppress multiple access interference (MAI) caused by a large number of sensor nodes. In WSNs, waveform division multiple access ultra-wideband (WDMA-UWB) technology is well suited for robust communications. Multiple sensor nodes are allowed to transmit modulated signals by sharing the same time periods and frequency bands using orthogonal pulse waveforms. This paper employs a mapping function based on the optimal multiuser detection to map the received bits into the mapping space where error bits can be distinguished. In order to revise error bits caused by MAI, the proposed joint MUD scheme combines the mapping function with suboptimal algorithms. Numerical results demonstrate that the proposed MUD scheme provides good performances in terms of suppressing MAI and resisting near-far effect with low computational complexity.

This paper presents a recent rainfall-induced landslide in China that occurred on August 21, 2020 and resulted in nine deaths. The sliding material traveled a distance of 800 m, with an altitude difference of about 180 m. A field investigation, remote sensing based on an unmanned aerial vehicle (UAV), in situ monitoring, and a rainfall data analysis were carried out to reveal the deposit characteristics, causative factors, post-landslide behavior, and the mechanism of the landslide. A saltatory micro-relief of the original slope determined the multiple-stage failure type of the slide, and also promoted the entrainment effect during the landslide movement. After the first-initiation sliding stage, the motion of this landslide involved typical progressive movement, and over time, the style of the runout generally turned into a flow-like form. Furthermore, the antecedent cumulative rainfall of 149.5 mm directly contributed to the occurrence of the landslide. Using the GB-SAR early warning system, the post-landslide residual failure was successfully predicted 10 min in advance. The combination of the UAV and GB-SAR technique can surely be beneficial for other inaccessible landslide investigations as well and improves the emergency rescue security.

Animals on the move often communicate with each other through some specific postures. Previous studies have shown that social interaction plays a role in communication process. However, it is not clear whether the affinity of group members can affect visual communication. We studied a group of free-ranging Tibetan macaques (Macaca thibetana) at Huangshan Mountain, China, and answered whether and how social centrality or relatives matter in visual signals during group movement using Tobit regression modeling. All individuals emitted the signals of back-glances and pauses in collective movement. The emission of two signals decreased with the number of participants increased. The back-glance and pause signals emitted by the participating individuals were stronger as the position moved backward in the group. Sex, age, and rank had no significant influence on back-glance and pause signals. Individuals with higher social centrality would emit more pause signals, but social centrality had no effect on the back-glance signal. Individuals with more relatives in the group had more back-glance signals, but this had no effect on the pause signal. This study verifies that social centrality and the number of relatives have effects on visual signals in Tibetan macaques. We provide insights into the relationship between communication behaviors and group cooperation in social animals.

Natural porous structure is extremely complex, and it is of great significance to study the macroscopic mechanical response of the representative volume element (RVE) with the microstructure of porous media. The real porous media RVE is generated by an improved quartet structure generation set (QSGS), and the connectivity of the reconstructed porous media models is analyzed. The fractal dimension of the RVE is calculated by the box-counting method, which considers the different porosity, different fractal dimension, and different mechanical properties of the matrix. Thus, the stress-strain curves of the RVE in the elastoplastic stage under different conditions are obtained. The results show that when the matrix mechanics are consistent, the mechanical properties of the porous media RVE are negatively correlated with the porosity and fractal dimension; when the difference between the porosity and fractal dimension increases, the trend is more obvious. The mechanical properties of the RVE have a positive correlation with the modulus of elasticity of the matrix, though the correlation with Poisson’s ratio of the matrix is weak. The fractal dimension of complex porous media can better predict the RVE mechanical characteristics than the porosity.

In order to investigate the impacts on the structure and biomedical function of typical fragments derived from repetitive and non-repetitive regions of the Bombyx mori silk fibroin heavy chain, several block combination genes (gs16f1, gs16f4, gs16f8, and gs16f12) were designed, cloned into a fusion protein expression vector tagged with glutathione S-transferase (GST), and expressed in Escherichia coli. Fusion proteins GST-GS16F1, GST-GS16F4, and GST-GS16F8 were purified by GST affinity chromatography, and single bands were identified by SDS-PAGE. Under optimal initial cell density, in ducer concentration and induction expression time, the yield of purified GST-GS16F1, GST-GS16F4, and GST-GS16F8 per liter of bacterial culture reached 79, 53, and 28 mg, respectively. Mass spectrometry revealed molecular weights for GST-GS16F1, GST-GS16F4, and GST-GS16F8 of 37.7, 50.0, and 65.7 kDa, respectively, consistent with the theoretical values of 37.4, 49.4, and 65.5 kDa. Similarly, measured values of pI were 5.35, 4.5, and 4.2 for the fusion proteins, consistent with predicted values of 5.34, 4.44, and 4.09. CD spectra showed the molecular conformation of GS16F1 was mainly β-sheet structure, while more stable α-helix structure formed in GS16F4 and GS16F8.

Al-doped ZnO has attracted much attention as a transparent electrode. The graphene-like ZnO monolayer as a two-dimensional nanostructure material shows exceptional properties compared to bulk ZnO. Here, through first-principle calculations, we found that the transparency in the visible light region of Al-doped ZnO monolayer is significantly enhanced compared to the bulk counterpart. In particular, the 12.5 at% Al-doped ZnO monolayer exhibits the highest visible transmittance of above 99%. Further, the electrical conductivity of the ZnO monolayer is enhanced as a result of Al doping, which also occurred in the bulk system. Our results suggest that Al-doped ZnO monolayer is a promising transparent conducting electrode for nanoscale optoelectronic device applications.