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The Chinese pangolin Manis pentadactyla is categorized as Critically Endangered on the IUCN Red List, but the development of effective conservation strategies is hindered by a lack of data on its distribution range and population dynamics. In addition, standardized survey and analysis methods are required to facilitate the sharing of results and maximize conservation effectiveness. To fill these knowledge and methodological gaps, we investigated the occurrence of pangolin burrows in the subtropical forest ecosystem of Fujian, China. We surveyed a total of 70 transects across five land-cover types within the Fujian Junzifeng National Nature Reserve and detected 87 burrows. The majority of burrows (87%) were located in mixed conifer and broadleaf forests. We used six environmental variables in a generalized linear model to examine the relationship between the occurrence of burrows and environmental factors. The average model results from the best model set showed that the distribution of burrows was significantly influenced by forest type. For effective pangolin conservation, we recommend that local conservation authorities prioritize the protection of mixed conifer and broadleaf forests. Our findings support the local conservation of the Chinese pangolin and the standardization of surveys and conservation efforts across the species’ range.
The automation of assembly operations with industrial robots is pivotal in modern manufacturing, particularly for multispecies, low-volume, and customized production. Traditional programing methods are time-consuming and lack adaptability to complex, variable environments. Reinforcement learning-based assembly tasks have shown success in simulation environments, but face challenges like the simulation-to-reality gap and safety concerns when transferred to real-world applications. This article addresses these challenges by proposing a low-cost, image-segmentation-driven deep reinforcement learning strategy tailored for insertion tasks, such as the assembly of peg-in-hole components in satellite manufacturing, which involve extensive contact interactions. Our approach integrates visual and forces feedback into a prior dueling deep Q-network for insertion skill learning, enabling precise alignment of components. To bridge the simulation-to-reality gap, we transform the raw image input space into a canonical space based on image segmentation. Specifically, we employ a segmentation model based on U-net, pretrained in simulation and fine-tuned with real-world data, significantly reducing the need for labor-intensive real image segment labels. To handle the frequent contact inherent in peg-in-hole tasks, we integrated safety protections and impedance control into the training process, providing active compliance and reducing the risk of assembly failures. Our approach was evaluated in both simulated and real robotic environments, demonstrating robust performance in handling camera position errors and varying ambient light intensities and different lighting colors. Finally, the algorithm was validated in a real satellite assembly scenario, achieving a success rate of 15 out of 20 tests.
This study investigated the factors influencing the mental health of rural doctors in Hebei Province, to provide a basis for improving the mental health of rural doctors and enhancing the level of primary health care.
Background:
The aim of this study was to understand the mental health of rural doctors in Hebei Province, identify the factors that influence it, and propose ways to improve their psychological status and the level of medical service of rural doctors.
Methods:
Rural doctors from 11 cities in Hebei Province were randomly selected, and their basic characteristics and mental health status were surveyed via a structured questionnaire and the Symptom Checklist-90 (SCL-90). The differences between the SCL-90 scores of rural doctors in Hebei Province and the Chinese population norm, as well as the proportion of doctors with mental health problems, were compared. Logistic regression was used to analyse the factors that affect the mental health of rural doctors.
Results:
A total of 2593 valid questionnaires were received. The results of the study revealed several findings: the younger the rural doctors, the greater the incidence of mental health problems (OR = 0.792); female rural doctors were more likely to experience mental health issues than their male counterparts (OR = 0.789); rural doctors with disabilities and chronic diseases faced a significantly greater risk of mental health problems compared to healthy rural doctors (OR = 2.268); rural doctors with longer working hours have a greater incidence of mental health problems; and rural doctors with higher education backgrounds have a higher prevalence of somatization (OR = 1.203).
Conclusion:
Rural doctors who are younger, male, have been in medical service longer, have a chronic illness or disability, and have a high degree of education are at greater risk of developing mental health problems. Attention should be given to the mental health of the rural doctor population to improve primary health care services.
In this article, we study an optimization problem for a couple including two breadwinners with uncertain life times. Both breadwinners need to choose the optimal strategies for consumption, investment, housing, and life insurance purchasing to maximize the utility. In this article, the prices of housing assets and investment risky assets are assumed to be correlated. These two breadwinners are considered to have dependent mortality rates to include the breaking heart effect. The method of copula functions is used to construct the joint survival functions of two breadwinners. The analytical solutions of optimal strategies can be achieved, and numerical results are demonstrated.
This study evaluated the effects of chenodeoxycholic acid (CDCA), a farnesoid X receptor (FXR) potential activator, on growth performance, antioxidant capacity, glucose metabolism and inflammation in largemouth bass (Micropterus salmoides) (initial body weight: 5·45 ± 0·02 g) fed a high-carbohydrate diet. Experimental diets included a positive control (5 % α-starch), a negative control (10 % α-starch) and two diets containing 10 % α-starch supplemented with either 0·05 % or 0·10 % CDCA. After 8 weeks, the high-carbohydrate diet reduced growth performance and increased hepatosomatic and viscerosomatic indexes, which were mitigated by 0·10 % CDCA supplementation. The high-carbohydrate diet also increased hepatic glycogen and crude lipid content, both of which were reduced by 0·10 % CDCA. Furthermore, the high-carbohydrate diet-induced oxidative stress, histopathological changes and reduced liver lysozyme activity, which were ameliorated by CDCA supplementation. Molecular analysis showed that the high-carbohydrate diet suppressed FXR and phosphorylated AKT1 (p-AKT1) protein expression in the liver, downregulated insulin signalling (ira, irs, pi3kr1 and akt1), gluconeogenesis (pepck and g6pc) and glycolysis genes (gk, pk and pfkl). CDCA supplementation upregulated fxr expression, activated shp, enhanced the expression of insulin signalling and glycolytic genes (gk, pk and pfkl) and inhibited gluconeogenesis. Additionally, CDCA reduced inflammatory markers (nf-κb and il-1β) and restored anti-inflammatory mediators (il-10, iκb and tgf-β). In conclusion, 0·10 % CDCA improved carbohydrate metabolism and alleviated liver inflammation in largemouth bass fed a high dietary carbohydrate, partially through FXR activation.
This paper provides an overview of the current status of ultrafast and ultra-intense lasers with peak powers exceeding 100 TW and examines the research activities in high-energy-density physics within China. Currently, 10 high-intensity lasers with powers over 100 TW are operational, and about 10 additional lasers are being constructed at various institutes and universities. These facilities operate either independently or are combined with one another, thereby offering substantial support for both Chinese and international research and development efforts in high-energy-density physics.
The Early-Middle Jurassic impression/compression macroflora and the palynoflora from the Qaidam Basin in the northeastern Qinghai-Xizang (Tibetan) Plateau have been well studied; however, fossil wood from this region has not been previously documented systematically. Here, we describe an anatomically well-preserved fossil wood specimen from the Lower Jurassic Huoshaoshan Formation at the Dameigou section in northern Qinghai Province, northwestern China. This fossil exhibits typical Metapodocarpoxylon Dupéron-Laudoueneix et Pons anatomy with usually araucarian radial tracheid pits and variable cross-field pits, representing a new record for Metapodocarpoxylon in the Qaidam Basin. This discovery indicates that trees with this type of wood anatomy were not confined to northern Gondwana but also grew in more northerly regions in Laurasia. The wood displays distinct growth rings, with abundant, well-formed earlywood and narrow latewood. This observation, along with previous interpretations based on macroflora, palynoflora and sedimentological data, suggests that a warm and humid climate with mild seasonality prevailed in the region during the Early Jurassic.
The ubiquitous marine radiocarbon reservoir effect (MRE) constrains the construction of reliable chronologies for marine sediments and the further comparison of paleoclimate records. Different reference values were suggested from various archives. However, it remains unclear how climate and MREs interact. Here we studied two pre-bomb corals from the Hainan Island and Xisha Island in the northern South China Sea (SCS), to examine the relationship between MRE and regional climate change. We find that the MRE from east of Hainan Island is mainly modulated by the Southern Asian Summer Monsoon-induced precipitation (with 11.4% contributed to seawater), rather than wind induced upwelling. In contrast, in the relatively open seawater of Xisha Island, the MRE is dominated by the East Asian Winter Monsoon, with relatively more negative (lower) ΔR values associated with high wind speeds, implying horizontal transport of seawater. The average SCS ΔR value relative to the Marine20 curve is –161±39 14C years. Our finding highlights the essential role of monsoon in regulating the MRE in the northern SCS, in particularly the tight bond between east Asian winter monsoon and regional MRE.
This study aimed to investigate the effects of physical multimorbidity on the trajectory of cognitive decline over 17 years and whether vary across wealth status. The study was conducted in 9035 respondents aged 50+ at baseline from nine waves (2002–2019) of the English Longitudinal Study of Aging. A latent class analysis was used to identify patterns of physical multimorbidity, and mixed multilevel models were performed to determine the association between physical multimorbidity and trajectories of cognitive decline. Joint analyses were conducted to further verify the influence of wealth status. Four patterns of physical multimorbidity were identified. Mixed multilevel models with quadratic terms of time and status/patterns indicated significant non-linear trajectories of multimorbidity on cognitive function. The magnitude of the association between complex multisystem patterns and cognitive decline increased the most as follow-up progressed. Individuals with high wealth and hypertension/diabetes patterns have significantly lower composite global cognitive z scores over time as compared with respiratory/osteoporosis patterns. Physical multimorbidity at baseline is associated with the trajectory of cognitive decline, and the magnitude of the association increased over time. The trend of cognitive decline differed in specific combinations of wealth status and physical multimorbidity.
This study examined the sour grapes/sweet lemons rationalization through 2 conditions: ‘attainable’ (sweet lemons) and ‘unattainable’ (sour grapes), reflecting China’s 2019-nCoV vaccination strategy. The aim was to find ways to change people’s beliefs and preferences regarding vaccines by easing their safety concerns and encouraging more willingness to get vaccinated. An online survey was conducted from January 22 to 27, 2021, with 3,123 residents across 30 provinces and municipalities in the Chinese mainland. The direction of belief and preference changed in line with the sour grapes/sweet lemons rationalization. Using hypothetical and real contrasts, we compared those for whom the vaccine was relatively unattainable (‘sour grapes’ condition) with those who could get the vaccine easily (‘sweet lemons’). Whether the vaccine was attainable was determined in the early stage of the vaccine roll-out by membership in a select group of workers that was supposed to be vaccinated to the greatest extent possible, or, by being in the second stage when the vaccine was available to all. The attainable conditions demonstrated higher evaluation in vaccine safety, higher willingness to be vaccinated, and lower willingness to wait and see. Hence, we propose that the manipulation of vaccine attainability, which formed the basis of the application of sour grapes/sweet lemons rationalization, can be utilized as a means to manipulate the choice architecture to nudge individuals to ease vaccine safety concerns, reducing wait-and-see tendencies, and enhancing vaccination willingness. This approach can expedite universal vaccination and its associated benefits in future scenarios resembling the 2019-nCoV vaccine rollout.
With the over-use of tetracycline (TC) and its ultimate accumulation in aquatic systems, the demand for TC removal from contaminated water is increasing due to its severe threat to public health. Clay minerals have attracted great attention as low-cost adsorbents for controlling water pollution. The objective of the present study was to measure the adsorption behavior and mechanisms of TC on allophane, a nanosized clay mineral with a hollow spherical structure; to highlight the advantage of the allophane nanostructure, a further objective was to compare allophane with halloysite and montmorillonite, which have nanostructures that differ from allophane. Structural features and surface physicochemical properties were characterized by transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), zeta potential, N2-physisorption, and acid–base titration. The adsorption data showed that TC adsorption followed the pseudo-second order and Langmuir models. The adsorption was pH dependent, as all three clay minerals performed better under neutral to weakly alkaline conditions and maintained high adsorption performance in the presence of co-existing Na+/K+/Ca2+/Mg2+ cations. Regeneration of the adsorbent was excellent, with efficiencies exceeding 75% after five recycles. By comparison, allophane always exhibited the greatest adsorption capacity, up to 796 mg g–1 at ~pH 9. The TC adsorption on allophane and halloysite was dominated by inner-sphere complexation, together with a small amount of electrostatic adsorption, while that on montmorillonite involved mainly interlayer cation exchange. The findings provide insights into the effects of nanostructures of clay minerals on their TC adsorption performance and highlight the huge potential of allophane as an efficient and inexpensive adsorbent for TC removal.
To investigate the associations between dietary patterns and biological ageing, identify the most recommended dietary pattern for ageing and explore the potential mediating role of gut microbiota in less-developed ethnic minority regions (LEMRs). This prospective cohort study included 8288 participants aged 30–79 years from the China Multi-Ethnic Cohort study. Anthropometric measurements and clinical biomarkers were utilised to construct biological age based on Klemera and Doubal’s method (KDM-BA) and KDM-BA acceleration (KDM-AA). Dietary information was obtained through the baseline FFQ. Six dietary patterns were constructed: plant-based diet index, healthful plant-based diet index, unhealthful plant-based diet index, healthy diet score, Dietary Approaches to Stop Hypertension (DASH), and alternative Mediterranean diets. Follow-up adjusted for baseline analysis assessed the associations between dietary patterns and KDM-AA. Additionally, quantile G-computation identified significant beneficial and harmful food groups. In the subsample of 764 participants, we used causal mediation model to explore the mediating role of gut microbiota in these associations. The results showed that all dietary patterns were associated with KDM-AA, with DASH exhibiting the strongest negative association (β = −0·91, 95 % CI (–1·19, −0·63)). The component analyses revealed that beneficial food groups primarily included tea and soy products, whereas harmful groups mainly comprised salt and processed vegetables. In mediation analysis, the Synergistetes and Pyramidobacter possibly mediated the negative associations between plant-based diets and KDM-AA (5·61–9·19 %). Overall, healthy dietary patterns, especially DASH, are negatively associated with biological ageing in LEMRs, indicating that Synergistetes and Pyramidobacter may be potential mediators. Developing appropriate strategies may promote healthy ageing in LEMRs.
This study aimed to explore the combined association between the dietary antioxidant quality score (DAQS) and leisure-time physical activity on sleep patterns in cancer survivors. Data of cancer survivors were extracted from the National Health and Nutrition Examination Surveys database in 2007–2014 in this cross-sectional study. Weighted multivariable logistic regression models were used to estimate OR and 95 % CI for the association of DAQS and leisure-time physical activity on sleep patterns. The combined association was also assessed in subgroups of participants based on age and use of painkillers and antidepressants. Among the eligible participants, 1133 had unhealthy sleep patterns. After adjusting for covariates, compared with low DAQS level combined with leisure-time physical activity level < 600 MET·min/week, high DAQS level combined with leisure-time physical activity ≥ 600 MET·min/week was associated with lower odds of unhealthy sleep patterns (OR = 0·41, 95 % CI: 0·23, 0·72). Additionally, the association of high DAQS level combined with high leisure-time physical activity with low odds of unhealthy sleep patterns was also significant in < 65 years old (OR = 0·30, 95 % CI: 0·13, 0·70), non-painkiller (OR = 0·39, 95 % CI: 0·22, 0·71), non-antidepressant (OR = 0·49, 95 % CI: 0·26, 0·91) and antidepressant (OR = 0·11, 95 % CI: 0·02, 0·50) subgroups. DAQS and leisure-time physical activity had a combined association on sleep patterns in cancer survivors. However, the causal associations of dietary nutrient intake and physical activity with sleep patterns in cancer survivors need further clarification.
The design of motion control systems for legged robots has always been a challenge. This article first proposes a motion control method for legged robots based on the gradient central pattern generator (GD-CPG). The periodic signals output from the GD-CPG neural network are used as the drive signals of each thigh joint of the legged robots, which are then converted into the driving signal of the knee and ankle joints by the thigh–knee mapping function and the knee–ankle mapping function. The proposed control algorithm is adapted to quadruped and hexapod robots. To improve the ability of legged robots to cope with complex terrains, this article further proposes the responsive gradient-CPG motion control method for legged robots. From the perspective of bionics, a biological vestibular sensory feedback mechanism is established in the control system. The mechanism adjusts the robot’s motion state in real time through the attitude angle of the body measured during the robot’s motion, to keep the robot’s body stable when it moves in rugged terrains. Compared with the traditional feedback model that only balances the body pitch, this article also adds the balancing functions of body roll and yaw to balance the legged robot’s motion from more dimensions and improve the linear motion capability. This article also introduces a differential evolutionary algorithm and designs a fitness function to adaptively optimize vestibular sensory feedback parameters. The validity, robustness, and transferability of the method are verified through simulations and physical experiments.
As a required sample preparation method for 14C graphite, the Zn-Fe reduction method has been widely used in various laboratories. However, there is still insufficient research to improve the efficiency of graphite synthesis, reduce modern carbon contamination, and test other condition methodologies at Guangxi Normal University (GXNU). In this work, the experimental parameters, such as the reduction temperature, reaction time, reagent dose, Fe powder pretreatment, and other factors, in the Zn-Fe flame sealing reduction method for 14C graphite samples were explored and determined. The background induced by the sample preparation process was (2.06 ± 0.55) × 10–15, while the 12C– beam current were better than 40μA. The results provide essential instructions for preparing 14C graphite of ∼1 mg at the GXNU lab and technical support for the development of 14C dating and tracing, contributing to biology and environmental science.
A new vacuum line to extract CO2 from carbonate and dissolved inorganic carbon (DIC) in water was established at Guangxi Normal University. The vacuum line consisted of two main components: a CO2 bubble circulation region and a CO2 purification collection region, both of which were made of quartz glass and metal pipelines. To validate its reliability, a series of carbonate samples were prepared using this system. The total recovery rate of CO2 extraction and graphitization exceeded 80%. Furthermore, the carbon content in calcium carbonate exhibited a linear relationship with the CO2 pressure within the system, demonstrating its stability and reliability. The system was also employed to prepare and analyze various samples, including calcium carbonate blanks, foraminiferal, shell, groundwater, and subsurface oil-water samples. The accelerator mass spectrometry (AMS) results indicated that the average beam current for 12C- in the samples exceeded 40 μA. Additionally, the contamination introduced during the liquid sample preparation process was approximately (1.77 ± 0.57) × 10−14. Overall, the graphitized preparation system for carbonate and DIC in water exhibited high efficiency and recovery, meeting the requirements for samples dating back to approximately 30,000 years.
Pulmonary atresia with intact ventricular septum and critical pulmonary stenosis usually have to undergo treatment in the neonatal period. Compared to traditional surgical intervention, catheter-based cardiac interventions may achieve similar or superior outcomes for neonates with pulmonary atresia with intact ventricular septum and critical pulmonary stenosis. However, there is limited literature on anaesthesia techniques, challenges, and risks associated with cardiac catheterisation in this population.
Methods:
This article retrospectively analysed the clinical data of pulmonary atresia with intact ventricular septum and critical pulmonary stenosis neonates who were treated with interventional cardiac catheterisation in our hospital from January 2015 to October 2022. Clinical outcomes considered were haemodynamic or pulse oxygen saturation instability, vasoactive requirements, prolonged intubation (>24 h postoperatively), and cardiovascular adverse events.
Results:
A total of 63 patients met the inclusion criteria. All patients survived the intervention. Among the patients with critical pulmonary stenosis, 40 successfully received percutaneous balloon pulmonary valvuloplasty, while three patients received ductal stenting due to moderate right ventricular dysplasia at the same time. For patients with pulmonary atresia with intact ventricular septum, 17 of the 23 patients successfully underwent percutaneous pulmonary valve perforation and percutaneous balloon pulmonary valvuloplasty. Of these, five patients underwent ductal stenting due to unstable pulmonary blood flow. Three patients only underwent ductal stenting. In addition, three patients received hybrid therapy.
Conclusions:
There are various clinical techniques and risk challenges in the interventional cardiac catheterisation of neonatal pulmonary atresia with intact ventricular septum and critical pulmonary stenosis. However, by mastering the physiological and pathophysiological characteristics of the disease, adequately preparing for the perioperative period, and predicting the procedure process and potential complications, anaesthesia and surgical risks can be effectively managed.
Autoimmune thyroiditis is closely associated with major depressive disorder (MDD) and suicide attempts. However, few studies have examined this relationship.
Aims
The study aimed to assess the prevalence and correlates of suicide attempts in patients with first-episode drug-naïve (FEDN) MDD and autoimmune thyroiditis.
Method
We recruited 1718 out-patients with FEDN MDD and assessed depressive, anxiety and psychotic symptoms with the Hamilton Rating Scale for Depression, Hamilton Rating Scale for Anxiety (HRSA) and Positive and Negative Syndrome Subscale positive subscale, respectively. The serum levels of free triiodothyronine, free thyroxine, thyroid stimulating hormone (TSH), antithyroglobulin, thyroid peroxidase antibody (TPOAb) and several other metabolic parameters were assessed. Patients were divided into non-autoimmune thyroiditis, autoimmune thyroiditis only and autoimmune thyroiditis with abnormal TSH groups, based on autoimmune thyroiditis severity. Multiple logistic regression model was applied to identify the correlates of suicide attempts in patients with MDD and autoimmune thyroiditis with abnormal TSH.
Results
Compared with the non-autoimmune thyroiditis group, the autoimmune thyroiditis with abnormal TSH group had a nearly fourfold higher likelihood of reporting a suicide attempt, whereas no difference was found between the non-autoimmune thyroiditis and autoimmune thyroiditis only groups. HRSA score, lnTPOAb and lnTSH were independently associated with suicide attempts in patients with autoimmune thyroiditis with abnormal TSH.
Conclusions
Patients with MDD and autoimmune thyroiditis with abnormal TSH are at higher risk for suicide attempt. TPOAb, TSH and anxiety are all independently associated with suicide attempts in this population, and regular thyroid checks are warranted.
As an important component of prehistoric subsistence, an understanding of bone-working is essential for interpreting the evolution of early complex societies, yet worked bones are rarely systematically collected in China. Here, the authors apply multiple analytical methods to worked bones from the Longshan site of Pingliangtai, in central China, showing that Neolithic bone-working in this area, with cervid as the main raw material, was mature but localised, household-based and self-sufficient. The introduction of cattle in the Late Neolithic precipitated a shift in bone-working traditions but it was only later, in the Bronze Age, that cattle bones were utilised in a specialised fashion and dedicated bone-working industries emerged in urban centres.