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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.
To evaluate the variations in COVID-19 case fatality rates (CFRs) across different regions and waves, and the impact of public health interventions, social and economic characteristics, and demographic factors on COVID-19 CFRs, we collected data from 30 countries with the highest incidence rate in three waves. We summarized the CFRs of different countries and continents in each wave through meta-analysis. Spearman’s correlation and multiple linear regression were employed to estimate the correlation between influencing factors and reduction rates of CFRs. Significant differences in CFRs were observed among different regions during the three waves (P < 0.001). An association was found between the changes in fully vaccinated rates (rs = 0.41), population density (rs = 0.43), the proportion of individuals over 65 years old (rs = 0.43), and the reduction rates of case fatality rate. Compared to Wave 1, the reduction rates in Wave 2 were associated with population density (β = 0.19, 95%CI: 0.05–0.33) and smoking rates (β = −4.66, 95%CI: −8.98 – −0.33), while in Wave 3 it was associated with booster vaccine rates (β = 0.60, 95%CI: 0.11–1.09) and hospital beds per thousand people (β = 4.15, 95%CI: 1.41–6.89). These findings suggest that the COVID-19 CFRs varied across different countries and waves, and promoting booster vaccinations, increasing hospital bed capacity, and implementing tobacco control measures can help reduce CFRs.
The tribological behavior can be informative about the incipient faults of robot manipulators. This study explores the evolution of friction characteristics from cold start to thermal equilibrium through a series of steady-state friction experiments. Based on these experimental observations, a friction-based fault diagnosis framework is proposed. The fault diagnosis process primarily involves defining the healthy state, decomposing friction curves and their features, and anomaly detection. Given the dependence of friction characteristics on different sources of faults, the parameters of steady-state experimental friction model are divided into two categories: one associated with contact interactions and the other related to non-contact regimes. Subsequently, confidence regions corresponding to distinguishable friction characteristics are independently constructed. These regions encapsulate the statistical description of the healthy state, characterized by mean values and the covariance of the friction characteristic parameter vectors during the unloaded state. In addition, we conduct experiments that consider the influence of applied loads on friction behavior. These experiments serve as a test set for comparison against nominal statistics. Leveraging the similarity between the effects of wear and load on friction, we introduce equivalent load thresholds to assess the severity of joint degradation. The results demonstrate the feasibility of employing confidence region views based on friction characteristic classification for fault detection and isolation.
Numerical simulations are carried out on the vortex-induced rotations of a freely rotatable rigid square cylinder in a two-dimensional uniform cross-flow. A range of Reynolds numbers between 40 and 150 and density ratios between 0.1 and 10 are considered. Results show eight different characteristic regimes, expanding the classification of Ryu & Iaccarino (J. Fluid Mech., vol. 813, 2017, pp. 482–507). New regimes include the transition and wavy rotation regimes; in the ${\rm \pi}$-limited oscillation regime we observe multipeak subregimes. Moment-generating mechanisms of these regimes and subregimes are further elucidated. A phenomenon related to the influence of density ratio is the tooth-like shape of the ${\rm \pi} /2$-limit oscillation regime observed in the regime map, which is explained as a result of the imbalance relation between the main frequencies of rotation response and the vortex shedding frequency. In addition, existence of multiple regimes and multistable states are discussed, indicating multiple stable attractive structures in phase space.
Compound words consist of two or more words which combine to form a single word or phrase that acts as one. In English, the head of compound words is usually, but not always, the right-most root (e.g., “paycheck” is a noun because the head, “check,” is a noun). The current study explores the effects of head position on language control by examining language switching performance through electroencephalography (EEG). Twenty-one pairs of Chinese (L1)–English (L2) bilinguals performed cued language switching in a simultaneous production and comprehension task. The results showed that bilinguals recognized the head position earlier both in production and comprehension. However, the language control of the head position during production occurred in the middle stage (N2), but in the late stage (LPC) during comprehension. These findings indicate that the head position in compound words exerts differential influences on language control.
The dual-user training system is essential for fostering motor skill learning, particularly in complex operations. However, the challenge lies in the optimal tradeoff between trainee ability and engagement level. To address this problem, we propose an intelligent agent that coordinates trainees’ control authority during real task engagement to ensure task safety during training. Our approach avoids the need for manually set control authority by expert supervision. At the same time, it does not rely on pre-modeling the trainee’s skill development. The intelligent agent uses a deep reinforcement learning (DRL) algorithm based on trainee performance to adjust adaptive engagement during the training process. Our investigation aims to provide reasonable engagement for trainees to improve their skills while ensuring task safety. Our results demonstrate that this system can seek the policy to maximize trainee participation while guaranteeing task safety.
Chemosensory proteins (CSPs) were necessary for insect sensory system to perform important processes such as feeding, mating, spawning, and avoiding natural enemies. However, their functions in non-olfactory organs have been poorly studied. To clarify the function of CSPs in the development of Mythimna separata (Walker) larvae, two CSP genes, MsCSP17 and MsCSP18, were identified from larval integument transcriptome dataset. Both of MsCSP17 and MsCSP18 contained four conserved cysteine sites (C × (6)-C × (18)-C × (2)-C), with a signal peptide at the N-terminal. RT-qPCR analysis showed that MsCSP17 and MsCSP18 have different expression patterns among different developmental stages and tissues. MsCSP17 was highly expressed in 1st–4th instar larvae, and MsCSP18 had high expression in adults. Both genes were expressed highly in larval head, thorax, integument and mandible. Moreover, both of MsCSP17 and MsCSP18 were lowly expressed in larval integuments when larvae molted for 6 h and 9 h from 3rd to 4th instar, but highly at the beginning and end phase during molting. After injection of dsMsCSP17 and dsMsCSP18, the expression levels of two genes decreased significantly, with the body weight of larvae decreased, the mortality increased, and the eclosion rate decreased. It was suggested that MsCSP17 and MsCSP18 contributed to the development of M. separata larvae.
We present the results of two population surveys conducted 10 years apart (December 2010–February 2011 and December 2020–January 2021) of the Critically Endangered white-headed langur Trachypithecus leucocephalus in the Chongzuo White-Headed Langur National Nature Reserve, Guangxi Province, China. In the first survey, we recorded 818 individuals in 105 groups and 16 solitary adult males. In the second survey, we recorded 1,183 individuals in 128 groups and one solitary adult male. As a result of government policies, poaching for food and traditional medicine is no longer a primary threat to these langurs. However, severe forest loss and fragmentation caused by human activities could limit any future increase of this langur population.
Planting patterns have significant effects on rice growth. Nonetheless, little is known about differences in annual crop yield and resource utilization among mechanized rice planting patterns in a rice–wheat cropping system. Field experiments were conducted from 2014 to 2017 using three treatments: pot seedling transplanting for rice and row sowing for wheat (PST-RS), carpet seedling transplanting for rice and row sowing for wheat (CST-RS) and row sowing for both crops (RS-RS). The results showed that, compared with RS-RS, PST-RS and CST-RS prolonged annual crop growth duration by 25–26 and 13–15 days, increased effective accumulated temperature by 399 and 212°C days and increased cumulative solar radiation by 454 and 228 MJ/m2 because of the earlier sowing of rice by 28 and 16 days in PST-RS and CST-RS, respectively. Compared with RS-RS, the annual crop yield of PST-RS and CST-RS increased by 3.1–3.8 and 2.0–2.6 t/ha, respectively, because of the increase in the number of spikelets/kernels per hectare, aboveground biomass, mean leaf area index and grain–leaf ratio. In addition, temperature production efficiency, solar radiation production efficiency and solar radiation use efficiency were higher in PST-RS, followed by CST-RS and RS-RS. These results suggest that mechanized rice planting patterns such as PST-RS increase annual crop production in rice–wheat cropping systems by increasing yield and solar energy utilization.
In this paper, the feasibility of a high laser damage threshold liquid crystal spatial light modulator based on gallium nitride (GaN) transparent conductive electrodes is proved. The laser-induced damage threshold (LIDT) is measured, and a high LIDT reflective optically addressed liquid crystal light valve (OALCLV) based on GaN is designed and fabricated. The proper work mode of the OALCLV is determined; the OALCLV obtained a maximum reflectivity of about 55% and an on–off ratio of 55:1, and an image response is demonstrated.
Routine coronavirus disease 2019 (COVID-19) screening found 1 asymptomatic COVID-19 patient. An emergency sampling team was organized consisting of 1200 health-care workers, and a total of 3.2228 million COVID-19 samples had been collected and detected. This study summarizes the on-site management experience in large-scale COVID-19 nucleic acid testing from various aspects: staff preparation, materials preparation, site layout, logistics support, and information system support. Suggestions are put forward for the deficiencies and parts needing improvement. Such deficiencies included some sampling sites were not properly chosen, different areas were unclearly marked off from each other, and some site moving lines were confounding; how to communicate with the street service workers who had little professional knowledge on the epidemic spread or the working principles of the workflow and site layout; and the way to resolve conflicts on site.
In this paper we employ a Gaussian-type heat kernel estimate to establish Krylov’s estimate and Khasminskii’s estimate for the Euler–Maruyama (EM) algorithm. For applications, by taking Zvonkin’s transformation into account, we investigate the convergence rate of the EM algorithm for a class of multidimensional stochastic differential equations (SDEs) with low regular drifts, which need not be piecewise Lipschitz.
Efficiently solving inverse kinematics (IK) of robot manipulators with offset wrists remains a challenge in robotics due to noncompliance with Pieper criteria. In this paper, an improved method to solve the IK for 6-DOF robot manipulators with offset wrists is proposed. This method is based on the Newton iteration technique, but it does not require a selection of initial estimation of joint variables. The solution is divided into two parts: the first part is to reconstruct a simplified structure with analytical IK solution, and the second part is to obtain a numerical solution by iteration. Further, a robot manipulator HSR-BR606 with an offset wrist is used as an example to specifically elaborate the mathematical procedure of the method and to investigate the algorithm in terms of accuracy, efficiency, and application of motion planning. A comparative experiment is conducted with a typical IK algorithm, which demonstrates a higher accuracy and shorter calculation time of the proposed method. The mean calculation time for a single IK solution required for this algorithm is only 4% of the comparison algorithm.
In this paper, we propose an effective method to compensate for the performance degradation of optically addressed spatial light modulators (OASLMs). The thermal deposition problem usually leads to the on-off ratio reduction of amplitude OASLM, so it is difficult to achieve better results in high-power laser systems. Through the analysis of the laser-induced temperature rise model and the liquid crystal layer voltage model, it is found that reducing the driving voltage of the liquid crystal light valve and increasing the driving current of the optical writing module can compensate for the decrease of on–off ratio caused by temperature rise. This is the result of effectively utilizing the photoconductive effect of Bi12SiO20 (BSO) crystal. The experimental results verify the feasibility of the proposed method and increase the laser withstand power of amplitude-only OASLM by about a factor of 2.5.
Primitive lamprophyres in orogenic belts can provide crucial insights into the nature of the subcontinental lithosphere and the relevant deep crust–mantle interactions. This paper reports a suite of relatively primitive lamprophyre dykes from the North Qiangtang, central Tibetan Plateau. Zircon U–Pb ages of the lamprophyre dykes range from 214 Ma to 218 Ma, with a weighted mean age of 216 ± 1 Ma. Most of the lamprophyre samples are similar in geochemical compositions to typical primitive magmas (e.g. high MgO contents, Mg no. values and Cr, with low FeOt/MgO ratios), although they might have experienced a slightly low degree of olivine crystallization, and they show arc-like trace-element patterns and enriched Sr–Nd isotopic composition ((87Sr/86Sr)i = 0.70538–0.70540, ϵNd(t) = −2.96 to −1.65). Those geochemical and isotopic variations indicate that the lamprophyre dykes originated from partial melting of a phlogopite- and spinel-bearing peridotite mantle modified by subduction-related aqueous fluids. Combining with the other regional studies, we propose that slab subduction might have occurred during Late Triassic time, and the rollback of the oceanic lithosphere induced the lamprophyre magmatism in the central Tibetan Plateau.
Solid solution 0.94Na0.5Bi0.5TiO3–6BaTiO3 (NBT–6BT) is considered to be one kind of lead-free piezoelectric materials with excellent electrical properties due to the existence of morphotropic phase boundary (MPB). However, its relatively lower depolarization temperature is a long-standing bottleneck for the application of NBT-based piezoelectric ceramics. In this work, the influence of thermal quenching on depolarization temperature and electrical properties of rare-earth Ho-doped NBT–6BT lead-free ceramics was investigated. It was shown that the relative high piezoelectric performance, as well as an improvement of depolarization temperature (Td), can be realized by thermal quenching. The results showed that the quenching process induced high concentration of oxygen vacancy, giving rise to the change of octahedra mode and enhanced lattice distortion, which is benefit to the temperature stability of piezoelectric and ferroelectric properties. Furthermore, up-conversion photoluminescence (PL) of Ho-doped NBT–6BT could be effectively tuned by the introduction of oxygen vacancy, suggesting a promising potential in optical–electrical multifunctional devices.
Community-acquired Staphylococcus aureus is a major pathogen responsible for skin and soft tissue infections (SSTIs). This study aimed to investigate the prevalence and molecular characteristics of community-acquired S. aureus isolates recovered from paediatric patients with SSTIs in Shanghai, China. Between January 2015 and January 2018, 91 community-acquired S. aureus isolates were characterised by antibiotic susceptibility, multilocus sequence typing (ST), staphylococcal protein A gene (spa) type and virulence genes. Methicillin-resistant S. aureus (MRSA) strains were also characterised by staphylococcal cassette chromosome mec (SCCmec) type. Forty-one (45.1%) S. aureus isolates were MRSA. ST59 (33.0%, 30/91) was the most common sequence type, and t437 (18.7%, 17/91) was the most common spa type. SCCmec IV and V accounted for 61.0% and 34.1% of all MRSA isolates, respectively. Each isolate carried at least six virulence genes. The positive rates of Panton-Valentine leukocidin genes among all S. aureus, MRSA and methicillin-susceptible S. aureus isolates were 30.8% (28/91), 39.0% (16/41) and 24% (12/50), respectively. The prevalence of community-associated MRSA was surprisingly high among children with community-acquired SSTIs in Shanghai. ST59-t437 was the most prevalent community-acquired S. aureus clone causing SSTIs.