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Force/motion transmissibility serves as an essential performance metric in the kinematic analysis of parallel mechanisms. The initial step in evaluating force/motion transmissibility involves identifying the basis elements of twist and wrench spaces. In parallel mechanisms consisting of PRS, RPS, SPR, and PU limbs, the identification of the basis elements of a given limb is relatively straightforward, as the limb constraints can be evaluated as pure forces and torques. However, in limbs where the axes of the joints are offset, determining these basis elements becomes quite complex. Typically, the constraints of these limbs involve the interconversion between general screws and line vectors or couples. This paper focuses on a 3-PRRU parallel mechanism. Procedures for identifying the basis elements are investigated. Screw theory is used to elucidate the relationships between the variations in the basis elements and the configurations of the mechanism. Moreover, the influence of an offset between two revolute joint axes on the force/motion transmissibility is systematically analyzed. The results indicate that, compared to the case without offsets, the introduction of offsets enhances the force transmissibility of the mechanism.
We present the design, construction and initial experimental validation of the Northwestern Polytechnical University Taylor–Couette (NPU-TC) apparatus, specifically developed to explore turbulent Taylor–Couette flows under conditions relevant to ultra-high-speed rotating machinery. The apparatus features an inner cylinder capable of rotating at speed of up to 10 000 rpm, corresponding to a Taylor number $Ta = 6.4 \times 10^8$, with an exceptionally narrow annular gap of 2.8 mm, yielding a radius ratio ($\eta$) of 0.98. Axial-scanning particle image velocimetry is employed here for the first time in air-based TC flows at such extreme conditions, which enables detailed velocity measurements without intrusive disturbances. Our velocity measurements demonstrate the absence of large-scale coherent flow structures, indicating a transition into the ultimate turbulence regime characterised by very thin boundary layers and nearly uniform velocity distributions in the bulk region. The NPU–TC apparatus thus represents a significant advance in experimental capabilities, providing critical insights into turbulent flow behaviour in high-speed rotating machinery.
Discrepancies in iodised salt coverage rate (ISCR) between household salt and that used in catering establishments may significantly compromise the accuracy of dietary iodine intake assessments. To evaluate this impact, we analysed data from the 2023 Shanghai Diet and Health Survey, a cross-sectional study involving 2920 adults. Dietary intake was assessed using three 24-h dietary recalls and an FFQ, while condiment intake was collected using the weighed inventory method. Additionally, salt samples from 960 canteens and restaurants were tested to determine the ISCR in dining establishments. Results showed that the ISCR was 85·9 % in dining establishments, markedly higher than the 53·3 % observed in households. Among employed participants in Shanghai, 51·7 %, 56·1 % and 18·7 % reported consuming breakfast, lunch and dinner outside the home at least once during the 3-d study period, respectively. The estimated daily iodine intake was 101 μg/d when dining-out salt was assumed to have the same ISCR as household salt, but it increased to 118 μg/d after accounting for the ISCR discrepancy. In conclusion, the rising prevalence of eating out has reshaped residents’ dietary habits, rendering traditional household-centric survey methods inadequate for iodine intake estimation in Shanghai. Incorporating ISCR differences between household and dining settings is essential for more accurate dietary iodine assessments.
Subthreshold depression (StD) is considered a prodromal stage of major depressive disorder (MDD). This study aims to investigate the neurobiological mechanisms of StD by analyzing functional connectivity (FC) and cognitive function in comparison to MDD.
Methods
A total of 153 StD individuals, 188 MDD patients, and 110 healthy controls (HCs) were studied using resting-state functional magnetic resonance imaging (fMRI). Whole-brain FC was calculated using seeds from the default mode network (DMN), salience network (SN), executive control network, and affective network (AN). Cognitive function was assessed across seven domains.
Results
StD showed only a deficit in social cognition, while MDD exhibited multidomain cognitive impairments compared to HCs. Both MDD and StD exhibited reduced FC between the right anterior insula (AI) and the left inferior frontal gyrus (IFG), and increased FC between the right subcallosal cingulate cortex and the left posterior cingulate cortex (PCC), key areas of the SN and AN, compared to HCs. MDD particularly showed decreased connectivity between the left PCC and the left middle temporal gyrus, and within the left PCC, while no abnormal FC of the DMN was found in StD. Altered AI-IFG FC was positively correlated with social cognition in StD.
Conclusions
Abnormal connectivity patterns of the SN and AN may contribute to the development of depressive symptoms in StD and MDD, while altered FC of the DMN may be involved in the onset of the disease. A social cognition deficit appeared first in StD, relating to the abnormal connectivity of the SN.
We investigated the influence of the slip velocity on particle migration in viscoelastic microchannel flows using a hybrid computational approach that coupled the lattice Boltzmann method with coarse-grained molecular dynamics. Our results demonstrate that the slip velocity changes lateral migration mechanisms by affecting the balance of inertial and elastic lift forces. In Newtonian fluids, forward slip drives particles toward the channel walls due to dominant inertial lift, while backward slip promotes migration toward the channel centreline. In viscoelastic fluids, however, slip-induced elastic lift forces arising from asymmetric polymer deformation around particles exceed inertial effects by an order of magnitude. This leads to a complete reversal of migration behaviour. We established that elastic lift scales linearly with the slip velocity and the block ratio, consistent with theoretical predictions, while polymer chain length influences elastic lift through a power-law dependence ($F_{e,s}^*\sim M^{1.66}$). These findings reveal that viscoelasticity-mediated slip effects provide a robust mechanism for particle manipulation in complex fluids. By connecting the microscopic polymer dynamics to macroscopic transport phenomena, our work offers new design principles for particle sorting and focusing applications in microfluidic systems.
We report here the characteristics of a high-power continuous-wave mid-infrared (mid-IR) fiber light source based on nested anti-resonant hollow-core fiber (AR-HCF) filled with HBr gas. A homemade hundred-watt-level 2 μm narrow-linewidth fiber laser is constructed as the pump source. The pump source is forward injected into the AR-HCF through a single-pass configuration. A maximum output power of 10.4 W at 4.16 μm with excellent beam quality (M2) of approximately 1.05 is achieved in a 4.8 m long AR-HCF at gas pressure of 9.9 mbar, with a slope efficiency of 20% relative to the absorbed pump power. The mid-IR light source maintains good stability during long-term operation. To the best of our knowledge, this is the highest output power for silica-based fiber light sources beyond 4 μm. This work demonstrates the significant capability of power scaling in a gas-filled AR-HCF mid-IR light source.
Although previous research has demonstrated that social media use (SMU) can influence loneliness, the underlying mechanisms of this relationship among older adults remain insufficiently understood. Specifically, limited research has examined how different purposes of SMU (communication, posting and browsing) may contribute to loneliness through variations in social resources, and for whom these pathways differ as a function of attachment styles. To address these gaps, the present study constructed a moderated mediation model to examine whether perceived social support mediated the relationships between different purposes of SMU and loneliness among older adults, and whether attachment styles moderated the mediation of perceived social support. A total of 538 older adults aged 55 and above participated in this survey. The results revealed that all purposes of SMU (communication, posting and browsing) were significantly and negatively associated with loneliness among older adults. Moreover, perceived social support fully mediated the association between social media communication and loneliness. In addition, attachment anxiety and avoidance moderated this indirect association, such that the protective effect of communication was stronger among older adults with higher attachment anxiety or avoidance, likely due to enhanced perceived social support. These findings emphasize the importance of social media communication in promoting mental wellbeing among older adults and highlight its potential to facilitate their social adaptation in the digital era.
Despite global efforts to end tuberculosis (TB), the goal of preventing catastrophic health expenditure (CHE) due to TB remains unmet. This cross-sectional study was conducted in Guizhou Province, Southwest China. Data were collected from the Hospital Information System and a survey of TB patients who had completed standardized antituberculosis treatment between January and March 2021. Among the 2 283 participants, the average total expenditure and out-of-pocket expenditure were $1 506.6 (median = $760.5) and $683.6 (median = $437.8), respectively. Health insurance reimbursement reduced CHE by 16.8%, with a contribution rate of 24.9%, and the concentration index changed from -0.070 prereimbursement to -0.099 postreimbursement. However, the contribution of health insurance varied significantly across different economic strata, with contribution rates of 6.4% for the lowest economic group and 53.1% for the highest group. For patients from lower socioeconomic strata, health insurance contributed 10.7% to CHE in the prediagnostic phase and 23.5% during treatment. While social health insurance alleviated the financial burden for TB patients, it did not provide sufficient protection for those in lower economic strata or during the prediagnostic stage. This study underscores the need for more effective and equitable subsidy policies for TB patients .
Sjögren's syndrome (SS) is a chronic autoimmune disease caused by immune system disorders. The main clinical manifestations of SS are dry mouth and eyes caused by the destruction of exocrine glands, such as the salivary and lacrimal glands, and systemic manifestations, such as interstitial pneumonia, interstitial nephritis and vasculitis. The pathogenesis of this condition is complex. However, this has not been fully elucidated. Treatment mainly consists of glucocorticoids, disease-modifying antirheumatic drugs and biological agents, which can only control inflammation but not repair the tissue. Therefore, identifying methods to regulate immune disorders and repair damaged tissues is imperative. Cell therapy involves the transplantation of autologous or allogeneic normal or bioengineered cells into the body of a patient to replace damaged cells or achieve a stronger immunomodulatory capacity to cure diseases, mainly including stem cell therapy and immune cell therapy. Cell therapy can reduce inflammation, relieve symptoms and promote tissue repair and regeneration of exocrine glands such as the salivary glands. It has broad application prospects and may become a new treatment strategy for patients with SS. However, there are various challenges in cell preparation, culture, storage and transportation. This article reviews the research status and prospects of cell therapies for SS.
Social determinants of health (SDoH), such as socioeconomics and neighborhoods, strongly influence health outcomes. However, the current state of standardized SDoH data in electronic health records (EHRs) is lacking, a significant barrier to research and care quality.
Methods:
We conducted a PubMed search using “SDOH” and “EHR” Medical Subject Headings terms, analyzing included articles across five domains: 1) SDoH screening and assessment approaches, 2) SDoH data collection and documentation, 3) Use of natural language processing (NLP) for extracting SDoH, 4) SDoH data and health outcomes, and 5) SDoH-driven interventions.
Results:
Of 685 articles identified, 324 underwent full review. Key findings include implementation of tailored screening instruments, census and claims data linkage for contextual SDoH profiles, NLP systems extracting SDoH from notes, associations between SDoH and healthcare utilization and chronic disease control, and integrated care management programs. However, variability across data sources, tools, and outcomes underscores the need for standardization.
Discussion:
Despite progress in identifying patient social needs, further development of standards, predictive models, and coordinated interventions is critical for SDoH-EHR integration. Additional database searches could strengthen this scoping review. Ultimately, widespread capture, analysis, and translation of multidimensional SDoH data into clinical care is essential for promoting health equity.
Direct numerical simulations of the droplet impact on a flat solid surface with an annular part are conducted. We investigate droplet impact on a superhydrophobic substrate with a superhydrophilic annulus to understand the formation conditions of droplets in different states. The location and size of superhydrophilic annulus are carried out through the phase diagram. We describe the formation process of droplets in three different states and the spreading radius with time to catch the rupture time of the film. Two different ruptures occur in the spreading stage or the retraction stage, respectively. The rupture times from these two mechanisms observed numerically are found to be a key factor resulting in partial rebound and lens-shaped/ring-shaped droplets. Finally, the influence of non-dimensional numbers on the formation of the ring-shaped droplet is demonstrated. The Weber number can alter the amplitude of the up and down oscillation on the droplet's upper surface, while the Froude number affects primarily the time to form the central penetrating hole. This gives the guidance and method to control the ring-shaped droplets formation time.
Autoimmune diseases are pathological autoimmune reactions in the body caused by various factors, which can lead to tissue damage and organ dysfunction. They can be divided into organ-specific and systemic autoimmune diseases. These diseases usually involve various body systems, including the blood, muscles, bones, joints and soft tissues. The transient receptor potential (TRP) and PIEZO receptors, which resulted in David Julius and Ardem Patapoutian winning the Nobel Prize in Physiology or Medicine in 2021, attracted people's attention. Most current studies on TRP and PIEZO receptors in autoimmune diseases have been carried out on animal model, only few clinical studies have been conducted. Therefore, this study aimed to review existing studies on TRP and PIEZO to understand the roles of these receptors in autoimmune diseases, which may help elucidate novel treatment strategies.
Genes involved in melanin production directly impact insect pigmentation and can affect diverse physiology and behaviours. The role these genes have on sex behaviour, however, is unclear. In the present study, the crucial melanin pigment gene black was functionally characterised in an urban pest, the German cockroach, Blattella germanica. RNAi knockdown of B. germanica black (Bgblack) had no effect on survival, but did result in black pigmentation of the thoraxes, abdomens, heads, wings, legs, antennae, and cerci due to cuticular accumulation of melanin. Sex-specific variation in the pigmentation pattern was apparent, with females exhibiting darker coloration on the abdomen and thorax than males. Bgblack knockdown also resulted in wing deformation and negatively impacted the contact sex pheromone-based courtship behaviour of males. This study provides evidence for black function in multiple aspects of B. germanica biology and opens new avenues of exploration for novel pest control strategies.
The laboratory generation and diagnosis of uniform near-critical-density (NCD) plasmas play critical roles in various studies and applications, such as fusion science, high energy density physics, astrophysics as well as relativistic electron beam generation. Here we successfully generated the quasistatic NCD plasma sample by heating a low-density tri-cellulose acetate (TCA) foam with the high-power-laser-driven hohlraum radiation. The temperature of the hohlraum is determined to be 20 eV by analyzing the spectra obtained with the transmission grating spectrometer. The single-order diffraction grating was employed to eliminate the high-order disturbance. The temperature of the heated foam is determined to be T = 16.8 ± 1.1 eV by analyzing the high-resolution spectra obtained with a flat-field grating spectrometer. The electron density of the heated foam is about under the reasonable assumption of constant mass density.
In preparation for an experiment with a laser-generated intense proton beam at the Laser Fusion Research Center at Mianyang to investigate the 11B(p,α)2α reaction, we performed a measurement at very low proton energy between 140 keV and 172 keV using the high-voltage platform at the Institute of Modern Physics, Lanzhou. The aim of the experiment was to test the ability to use CR-39 track detectors for cross-section measurements and to remeasure the cross-section of this reaction close to the first resonance using the thick target approach. We obtained the cross-section σ = 45.6 ± 12.5 mb near 156 keV. Our result confirms the feasibility of CR-39 type track detector for nuclear reaction measurement also in low-energy regions.
Isomorphous substitutions of Mg and Fe for Al generally appear in the octahedral sheets of montmorillonite, whereas they are infrequent in kaolinite. Therefore, the release of Mg and Fe from the octahedral sheets probably happens during the transformation of montmorillonite into kaolinite, which could affect the migration of Mg and Fe from clay minerals into surrounding environments. The objective of the current study was to investigate the relationship between Mg and Fe release during the transformation of montmorillonite into kaolinite. The results showed that the d060 value of clay minerals decreased slightly, and the intensities of both the AlMg–OH and AlFe–OH bending vibrations also decreased gradually. In addition, the (Mg+Fe)/Al (major octahedral ions) atomic ratio of kaolinite was lower than that of montmorillonite, especially in identical hydrothermal products. These results indicated that Mg and Fe ions were released progressively from the octahedral sheets during the transformation of montmorillonite into kaolinite. Moreover, the changed relative concentrations of Mg and Fe ions in the supernatant solutions after hydrothermal reactions suggested a random distribution of Mg and/or Fe in the octahedral sheets of the montmorillonite. These results improve understanding of the release relationship between Mg and Fe during clay mineral evolution and of the distribution of these two ions in the octahedral sheets, as well as the chemical composition of clay minerals as an indicator of geological environments.
During the early stages of human pregnancy, successful implantation of embryonic trophoblast cells into the endometrium depends on good communication between trophoblast cells and the endometrium. Abnormal trophoblast cell function can cause embryo implantation failure. In this study, we added cyclosporine A (CsA) to the culture medium to observe the effect of CsA on embryonic trophoblast cells and the related mechanism. We observed that CsA promoted the migration and invasion of embryonic trophoblast cells. CsA promoted the expression of leukaemic inhibitory factor (LIF) and fibroblast growth factor (FGF). In addition, CsA promoted the secretion and volume increase in vesicles in the CsA-treated group compared with the control group. Therefore, CsA may promote the adhesion and invasion of trophoblast cells through LIF and FGF and promote the vesicle dynamic process, which is conducive to embryo implantation.
This study assesses the difference in professional attitudes among medical students, both before and after coronavirus disease 2019 (COVID-19), and identifies the determinants closely associated with it, while providing precise and scientific evidence for implementing precision education on such professional attitudes.
Methods:
A pre-post-like study was conducted among medical students in 31 provinces in mainland China, from March 23, to April 19, 2021.
Results:
The proportion of medical students whose professional attitudes were disturbed after the COVID-19 pandemic, was significantly lower than before the COVID-19 pandemic (χ2 = 15.6216; P < 0.0001). Compared with the “undisturbed -undisturbed” group, the “undisturbed-disturbed” group showed that there was a 1.664-fold risk of professional attitudes disturbed as grade increased, 3.269-fold risk when others suggested they choose a medical career rather than their own desire, and 7.557-fold risk for students with COVID-19 in their family, relatives, or friends; while the “disturbed-undisturbed” group showed that students with internship experience for professional attitudes strengthened was 2.933-fold than those without internship experience.
Conclusions:
The professional attitudes of medical students have been strengthened during the COVID-19 pandemic. The results provide evidence of the importance of education on professional attitudes among medical students during public health emergencies.
The relationships between childhood weight self-misperception and obesity-related factors particularly health markers have not been extensively discussed. This study aims to examine the associations between weight self-misperception and obesity-related knowledge, attitudes, lifestyles and cardio-metabolic markers among Chinese paediatric population.
Design:
Cross-sectional study.
Setting:
Data sourced from a national survey in Chinese seven provinces in 2013.
Participants:
Children and adolescents aged 5–19 years.
Results:
Of the total 14 079 participants, there were 14·5 % and 2·2 % participants over-estimated and under-perceived their weight, respectively. Multi-variable logistic regression was applied to calculate OR and 95 % CI (95 % Cl) of obesity-related behaviours and cardio-metabolic markers by actual and perceived weight status. Individuals who perceived themselves as overweight/obese were more likely to have prolonged screen time, insufficient dairy intake and over sugar-sweetened beverages consumption (all P < 0·05), regardless of their weight. Furthermore, actual overweight/obese individuals had higher odds of abnormal cardio-metabolic markers, but a smaller magnitude of association was found among weight under-estimators. Among non-overweight/obese individuals, weight over-estimation was positively associated with abdominal obesity (OR: 10·49, 95 % CI: 7·45, 14·76), elevated blood pressure (OR: 1·30, 95 % CI: 1·12, 1·51) and dyslipidemia (OR: 1·43, 95 % CI: 1·29, 1·58).
Conclusions:
Weight over-perception was more prevalent than under-estimation, particularly in girls. Weight over-estimators tended to master better knowledge but behave more unhealthily; both weight over-perception and actual overweight/obesity status were associated with poorer cardio-metabolic markers. Future obesity intervention programmes should additionally pay attention to the population with inaccurate estimation of weight who were easily overlooked.
The G protein-coupled receptors (GPCR) sensing nutritional signals (amino acids, fatty acids, glucose, etc.) are not fully understood. In this research, we used transcriptome sequencing to analyse differentially expressed genes (DEG) in mouse mammary gland tissues at puberty, lactation and involution stages, in which eight GPCR were selected out and verified by qRT-PCR assay. It was further identified the role of GPR110-mediating nutrients including palmitic acid (PA) and methionine (Met) to improve milk synthesis using mouse mammary epithelial cell line HC11. PA but not Met affected GPR110 expression in a dose-dependent manner. GPR110 knockdown decreased milk protein and fat synthesis and cell proliferation and blocked the stimulation of PA on mechanistic target of rapamycin (mTOR) phosphorylation and sterol-regulatory element binding protein 1c (SREBP-1c) expression. In summary, these experimental results disclose DEG related to lactation and reveal that GPR110 mediates PA to activate the mTOR and SREBP-1c pathways to promote milk protein and fat synthesis.