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Abstract Analogous to the condensation of Cooper pairs in superconductors, the Bose–Einstein condensation (BEC) of electron–hole pairs in semiconductors and semimetals leads to an emergence of an exotic ground state — the excitonic insulator state. In this paper, we study the electronic structure of 1T-TiSe2 utilizing angle-resolved photoemission spectroscopy and alkali-metal deposition. Alkali-metal adatoms are deposited in-situ on the sample surface, doping the system with electrons. The conduction bands of 1T-TiSe2 are thereby pushed down below the Fermi energy, which enables us to characterize its temperature dependence with precision. We found that the formation of the charge density wave (CDW) in 1T-TiSe2 at ~ 205 K is accompanied by a significant increase of the band gap, supporting the existence of excitonic pairing in the CDW state of 1T-TiSe2. More importantly, by analyzing the linewidth of the single-particle excitation spectrum, we unveiled an incoherence-to-coherence crossover at 165 K, which could be attributed to a possible exciton condensation that occurs beneath the CDW transition in 1T-TiSe2. Our results not only explain the exotic transport properties of 1T-TiSe2, but also highlight the possible existence of an excitonic condensate in this semiconducting material.

Abstract Objectives To systematically evaluate the therapeutic effect of electrical stimulation combined with pelvic floor muscle exercise on female pelvic floor dysfunction (PFD). Methods Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was applied. A computer-based retrieval was performed in the databases of PubMed, Web of Science, Embase, and Cochrane Library from database establishment to September 15, 2023, to identify randomized controlled trials on electrical stimulation combined with pelvic floor muscle function exercise on female PFD. Literature screening, data extraction, and quality evaluation were performed independently by two researchers, and meta-analysis was performed using the statistical software Stata15.0. Results 1. In total, 12 randomized controlled trials were included, involving 721 female patients. The overall quality of methodologies employed in the included studies was relatively high. 2. Meta-analysis results showed that electrical stimulation combined with pelvic floor muscle exercise could effectively mitigate the severity of female PFD (SMD = -1.01, 95% CI − 1.78, − 0.25, P 0.05). Conclusions Compared with pelvic floor muscle exercise alone, electrical stimulation combined with pelvic floor muscle exercise could effectively mitigate the severity of female PFD. It had a notable positive impact on enhancing pelvic floor muscle strength in female patients, although it did not significantly improve quality of life. Future high-quality studies are warranted.

Abstract Background To investigate the prognostic value of corpus uterine invasion (CUI) in cervical cancer (CC), and determine the necessity to incorporate it for staging. Methods A total of 809 cases of biopsy‐proven, non‐metastatic CC were identified from an academic cancer center. Recursive partitioning analysis (RPA) method was used to develop the refined staging systems with respect to overall survival (OS). Internal validation was performed by using calibration curve with 1000 bootstrap resampling. Performances of the RPA‐refined stages were compared against the conventional FIGO 2018 and 9th edition TNM‐stage classifications by the receiver operating characteristic curve (ROC) and decision curve analysis (DCA). Results We identified that CUI was independently prognostic for death and relapse in our cohort. RPA modeling using a two‐tiered stratification by CUI (positive and negative) and FIGO/T‐categories divided CC into three risk groupings (FIGO I′‐III'/T1′‐3′), with 5‐year OS of 90.8%, 82.1%, and 68.5% for proposed FIGO stage I′–III', respectively (p ≤ 0.003 for all pairwise comparisons), and 89.7%, 78.8%, and 68.0% for proposed T1′‐3′, respectively (p

Abstract Diabetic ulcers (DUs) are one of the most serious complications of diabetes mellitus. The application of a functional dressing is a crucial step in DU treatment and is associated with the patient's recovery and prognosis. However, traditional dressings with a simple structure and a single function cannot meet clinical requirements. Therefore, researchers have turned their attention to advanced polymer dressings and hydrogels to solve the therapeutic bottleneck of DU treatment. Hydrogels are a class of gels with a three-dimensional network structure that have good moisturizing properties and permeability and promote autolytic debridement and material exchange. Moreover, hydrogels mimic the natural environment of the extracellular matrix, providing suitable surroundings for cell proliferation. Thus, hydrogels with different mechanical strengths and biological properties have been extensively explored as DU dressing platforms. In this review, we define different types of hydrogels and elaborate the mechanisms by which they repair DUs. Moreover, we summarize the pathological process of DUs and review various additives used for their treatment. Finally, we examine the limitations and obstacles that exist in the development of the clinically relevant applications of these appealing technologies. Graphical Abstract This review defines different types of hydrogels and carefully elaborate the mechanisms by which they repair diabetic ulcers (DUs), summarizes the pathological process of DUs, and reviews various bioactivators used for their treatment.

Objective: To determine whether exoskeleton-assisted walking (EAW) improves pulmonary ventilation function, motor function and related body structure, and activities equivalently as the conventional exercise program for people with spinal cord injury (SCI). Methods: Forty participants (7 females and 33 males; age 37.1±12.0 years) with thoracic SCI were randomized into two groups and undertook 16 sessions of 50–60 min training (4 days/week). Participants in the EAW group received EAW trainings, such as assisted standing, walking, and climbing the stairs. The control group received a conventional exercise program. Outcomes were measured at baseline and upon completion of treatment. Results: After trainings, the EAW group improved more than the control group in the forced vital capacity (FVC, 0.53 L [0.01–1.06 L]), predicted FVC% (19.59 [6.63–32.54]) and forced expiratory volume in 1s (0.61 L [0.15–1.07 L]), basic activities of daily living (BADL) (19.75 [10.88–28.62]), and distal femoral cartilage. Participants in the EAW group completed 6-minute walk test with median 17.3 meters while wearing the exoskeleton. There was no difference in trunk and lower extremity motor function, bone mineral density, and adverse events ( ${P}$ > 0.05). Conclusion: In people with lower thoracic neurological level of SCI, EAW training has potential benefits to facilitate pulmonary ventilation function, walking, BADL and thickness of cartilage comparing to a conventional excise program. Significance: This study provided more evidence for using EAW in clinic, and partly proved EAW had equivalent effects as conventional exercise program, which may combine with conventional exercise program for reducing burden of therapists in the future.

Abstract Background The purpose of present study was to reveal the molecular mechanisms responsible for both adipogenic differentiation and dedifferentiation of mesenchymal stem cells (MSCs). Methods Microarray data GSE36923 were obtained from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) between adipogenically differentiated cells vs undifferentiated bone marrow-derived MSCs, adipogenically differentiated cells vs dedifferentiated cells samples at day 7 and adipogenically differentiated cells vs dedifferentiated cells samples at day 35 were screened, and overlapped DEGs across the three groups were analyzed. The underlying functions of the upregulated and downregulated DEGs were investigated by Gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analysis. The protein–protein interaction network was constructed, and hub genes were obtained subsequently. Hub genes were verified with GSE113253 dataset, and then miRNA-gene network and TF-gene network were constructed. Results A total of 284 upregulated DEGs and 376 downregulated DEGs overlapped across the three groups. PPAR signaling pathway, AMPK signaling pathway, insulin signaling pathway, carbon metabolism, pyruvate metabolism, fatty acid metabolism, regulation of lipolysis in adipocytes, biosynthesis of amino acids, citrate cycle (TCA cycle) and 2-Oxocarboxylic acid metabolism were the top 10 pathways involving in the upregulated DEGs, and graft-versus-host disease, allograft rejection, viral myocarditis, cell adhesion molecules, phagosome, type I diabetes mellitus, antigen processing and presentation, autoimmune thyroid disease, intestinal immune network for IgA production and rheumatoid arthritis were the top 10 pathways in downregulated DEGs. After validation, the 8 hub genes were IL6, PPARG, CCL2, FASN, CEBPA, ADIPOQ, FABP4 and LIPE. Ten key miRNAs were hsa-mir-27a-3p, hsa-mir-182-5p, hsa-mir-7-5p, hsa-mir-16-5p, hsa-mir-1-3p, hsa-mir-155-5p, hsa-mir-21-3p, hsa-mir-34a-5p, hsa-mir-27a-5p and hsa-mir-30c-5p, and 10 key TFs were TFDP1, GTF2A2, ZNF584, NRF1, ZNF512, NFRKB, CEBPG, KLF16, GLIS2 and MXD4. Conclusion Our study constructed miRNA-gene network and TF-gene network involved in both adipogenic differentiation and dedifferentiation of MSCs, contributing to enhancing the efficiency of MSCs transplantation in soft tissue defect repair and developing more potent remedies for adipogenesis-related skeletal disorders.

Abstract Background Complex acetabular fractures involving the anterior and posterior columns are an intractable clinical challenge. The study investigated the safety and efficacy of oblique-ilioischial plate technique for acetabular fractures involving low posterior column. Methods A retrospective analysis of 18 patients operated with the oblique-ilioischial plate technique by the modified Stoppa approach (or combined with iliac fossa approach) between August 2016 and July 2021 for low posterior column acetabular fractures was conducted. The anterior column was fixed with a reconstructed plate from the iliac wing along the iliopectineal line to the pubis. The low posterior column was fixed with the novel oblique-ilioischial plate running from the ilium to the ischial ramus. Operative time, intraoperative blood loss, reduction quality, and postoperative hip function were recorded. Results Out of the 18 patients, 10 were male and 8 were female. The mean age was 48.6±10.2 years (range: 45–62 years); The mean interval from injury to operation was 7.2±1.4 days (range: 5–19 days); The mean operative time was 2.1±0.3 h (range: 1.0–3.2 hours); The mean intraoperative blood loss was 300±58.4 mL (range: 200–500 mL). Postoperative reduction (Matta’s criteria) was deemed as excellent (n = 9), good (n = 4), and fair (n = 5). At the final follow-up, the hip function (modified Merle d’Aubigne-Postel scale) was deemed as excellent (n = 11), good (n = 3), and fair (n = 4). The mean union time was 4.5±1.8 months (range: 3–6 months). No implant failure, infection, heterotopic ossification, or neurovascular injury were reported. Conclusion The oblique-ilioischial plate technique via anterior approach for acetabular fractures involving low posterior column offers reliable fixation, limited invasion, little intraoperative bleeding, and fewer complications. However, larger multicenter control studies are warranted.

Background: To investigate the prognostic role of pretreatment squamous cell carcinoma antigen (SCCA) in early-stage cervical cancer (CC). Methods: We enrolled 487 cases of pathology-proven early-stage [International Federation of Gynecology and Obstetrics (FIGO) I/II] squamous or adenosquamous CC that were treated from 2012 to 2015. Restricted cubic splines (RCS) with a full Cox regression model were used to evaluate the association between SCCA levels and survival outcomes. Recursive partitioning analysis (RPA) was used to construct a risk stratification model for overall survival (OS). The performance of the RPA-based model was assessed using a receiver operating characteristic (ROC) curve. Results: RCS analysis revealed an association between SCCA and OS and disease-free survival (DFS); SCCA ⩾2.5 ng/mL was robust for risk discrimination in our cohort. SCCA had an interaction effect with FIGO classification: Patients with FIGO I and SCCA ⩾2.5 ng/mL overlapped with those with FIGO II and SCCA

A method of designing and fabricating substrate-free Au/SiNx/Au metafilms as the terahertz (THz) absorber of metamaterial focal plane arrays (MFPA) is reported. The absorption was investigated by the finite integration method simulation and new explicit functions. The substrate-free structure was well fabricated by microelectromechanical system (MEMS) technology. The frequency-dependent absorption of MFPA was measured by THz time-domain spectroscopy (THz-TDS) system. It exhibits an extremely high absorptance of 98.7% at 1.36 THz. The absorption characteristic shows an asymmetric profile, which is well fitted with an Asymmetric Double Sigmoidal (Asym2sig) model. Our results show that the Au/SiNx/Au metafilms have potential in optical readout THz real-time imaging, and highly sensitive sensing applications.

The southern Tibetan Plateau (TP) is snow covered during cold season but exhibits faster snow melting in early summer. Using in situ observations and improved satellite-derived data, the present study indicates that the snow depth (SD) over the southern TP exhibits distinction characteristics between late spring (i.e., P1: April 16th–May 15th) and early summer (i.e., P2: May 16th–June 14th). In terms of climate states, the snow melting rate over the southern TP in P2 is faster than that in P1. The acceleration of snow melting during P2 is mainly found over high elevation areas caused by the increase of local air temperature. Diagnoses of the thermodynamic equation further demonstrate that the warming over the southern TP during the two periods is mainly attributed to the meridional temperature advection and diabatic heating in situ. On the interannual time scale, the SD over the southern TP is closely related to diabatic heating over South Asia. During P1, the diabatic cooling from the southern Bay of Bengal eastward to the western South China Sea suppresses convection over the Bay of Bengal and southern TP and has resulted in an upper-level anomalous cyclone and cold temperature anomalies from the surface to 200 hPa over the southern TP, favoring the above-normal SD over the southern TP. On the other hand, SD over the southern TP in P2 is closely related to diabatic cooling over the northern Indochina Peninsula and diabatic heating over the southern China. But we could not prove that these diabatic heating anomalies can affect the SD over the southern TP by modulating local surface air temperature. This may be limited by the quality of the data and the simulation capability of the simple model.

Abstract Background Exoskeleton-assisted walking (EAW) is expected to improve the gait of spinal cord injury (SCI) individuals. However, few studies reported the changes of pulmonary function (PF) parameters after EAW trainings. Hence, we aimed to explore the effect of EAW on PF parameters, 6-min walk test (6MWT) and lower extremity motor score (LEMS) in individuals with SCI and to compare those with conventional trainings. Methods In this prospective, single-center, single-blinded randomized controlled pilot study, 18 SCI participants were randomized into the EAW group (n = 9) and conventional group (n = 9) and received 16 sessions of 50–60 min training (4 days/week, 4 weeks). Pulmonary function parameters consisting of the forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), forced expiratory flow (FEF), peak expiratory flow, and maximal voluntary ventilation, 6MWT with assisted devices and LEMS were reported pre- and post-training. Results Values of FVC (p = 0.041), predicted FVC% (p = 0.012) and FEV1 (p = 0.013) were significantly greater in EAW group (FVC: 3.8 ± 1.1 L; FVC% pred = 94.1 ± 24.5%; FEV1: 3.5 ± 1.0 L) compared with conventional group (FVC: 2.8 ± 0.8 L; FVC% pred = 65.4 ± 17.6%; FEV1: 2.4 ± 0.6 L) after training. Participants in EAW group completed 6MWT with median 17.3 m while wearing the exoskeleton. There was no difference in LEMS and no adverse event. Conclusions The current results suggest that EAW has potential benefits to facilitate PF parameters among individuals with lower thoracic neurological level of SCI compared with conventional trainings. Additionally, robotic exoskeleton helped walking. Trial registration: Registered on 22 May 2020 at Chinese Clinical Trial Registry (ChiCTR2000033166). http://www.chictr.org.cn/edit.aspx?pid=53920&htm=4 .

Naproxen is widely used for anti-inflammatory treatment but it can lead to serious side effects. To improve the anti-inflammatory activity and safety, a novel naproxen derivative containing cinnamic acid (NDC) was synthesized and used in combination with resveratrol. The results showed that the combination of NDC and resveratrol at different ratios have a synergistic anti-inflammatory efficacy in RAW264.7 macrophage cells. It was indicated that the combination of NDC and resveratrol at a ratio of 2:1 significantly inhibited the expression of carbon monoxide (NO), tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), induced nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2) and reactive oxygen species (ROS) without detectable side effects on cell viability. Further studies revealed that these anti-inflammatory effects were mediated by the activation of nuclear factor kappa-B (NF-κB), mitogen-activated protein kinase (MAPK) and phosphoinositide-3 kinase (PI3K)/protein kinase B (Akt) signaling pathways, respectively. Taken together, these results highlighted the synergistic NDC and resveratrol anti-inflammatory activity that could be further explored as a strategy for the treatment of inflammatory disease with an improved safety profile.

Since its outbreak in December 2019, a series of clinical trials on coronavirus disease 2019 (COVID-19) have been registered or carried out. However, the significant heterogeneity and less critical outcomes of such trials may be leading to a waste of research resources. This study aimed to develop a core outcome set (COS) for clinical trials on COVID-19 in order to tackle the outcome issues. The study was conducted according to the Core Outcome Measures in Effectiveness Trials (COMET) Handbook: Version 1.0, a guideline for COS development. A research group was set up that included experts in respiratory and critical medicine, traditional Chinese medicine (TCM), evidence-based medicine, clinical pharmacology, and statistics, in addition to medical journal editors. Clinical trial registry websites (www.chictr.org.cn and clinicaltrials.gov) were searched to retrieve clinical trial protocols and outcomes in order to form an outcome pool. A total of 78 clinical trial protocols on COVID-19 were included and 259 outcomes were collected. After standardization, 132 outcomes were identified within seven different categories, of which 58 were selected to develop a preliminary outcome list for further consensus. After two rounds of Delphi survey and one consensus meeting, the most important outcomes for the different clinical classifications of COVID-19 were identified and determined to constitute the COS for clinical trials on COVID-19 (COS-COVID). The COS-COVID includes one outcome for the mild type (time to 2019 novel coronavirus (2019-nCoV) reverse transcription-polymerase chain reaction (RT-PCR) negativity), four outcomes for the ordinary type (length of hospital stay, composite events, score of clinical symptoms, and time to 2019-nCoV RT-PCR negativity), five outcomes for the severe type (composite events, length of hospital stay, arterial oxygen partial pressure (PaO2)/fraction of inspired oxygen (FiO2), duration of mechanical ventilation, and time to 2019-nCoV RT-PCR negativity), one outcome for critical type (all-cause mortality), and one outcome for rehabilitation period (pulmonary function). The COS-COVID is currently the most valuable and practical clinical outcome set for the evaluation of intervention effect, and is useful for evidence assessment and decision-making. With a deepening understanding of COVID-19 and application feedback, the COS-COVID should be continuously updated.

Abstract The ability of simultaneous polarization filter and wavefront shaping is very important for many applications, especially for polarization imaging. However, traditional methods rely on complex combinations of bulky optical components, which not only hinder the miniaturization and integration but also reduce the efficiency and imaging quality. Metasurfaces have shown extraordinary electromagnetic properties to manipulate the amplitude, polarization, and wavefront. Unfortunately, multi-layer metasurfaces with complex fabrication are often required to realize complex functions. Here, a platform of monolayer all-dielectric metasurfaces is proposed to simultaneously achieve polarization filtering and wavefront shaping, based on the principle of local polarization-selective constructive or destructive interference. The transmission efficiency surpassing 0.75 and polarization extinction ratio exceeding 11.6 dB are achieved by the proposed metasurface at the wavelength of 10.6 μm. These results are comparable to those of multi-layer metasurfaces. Considering these good performances, this work may prove new ideas for the generation of complex optical field and find wide applications in polarization imaging.

Simulation emergency evacuation is an important part in the field of safety engineering, affective computing plays a vital role in the popularization of artificial intelligence, computer simulation and human-computer interaction. Inspired by this field, this paper proposes a method for simulating group interactions during emergency evacuation. First, each individual is assigned with dynamic survival needs and psychological quality based on urgent event and the external influence. Second, the emotional interaction of the group is realized based on OCEAN (Openness, Conscientiousness, Extroversion, Agreeableness, Neuroticism) personality trait and the improved CA-SIRS (Cellular Automaton-Susceptible Infected Recovered Susceptible) model. Third, after the perception of the external environment changes, the accident experience and panic level are used as factors of emotion update. At last, the environmental familiarity and nearby flow factors are introduced to path planning process. Based on emotion contagion, this method explores individual's emotional changes in different scenarios and situations. Combined with personality traits and emotional contagion, the experimental results show that the proposed method can simulate dynamic emotional changes in emergency situations in both efficient and reasonable way and provide guidance for emergency evacuation.

Intracerebral hemorrhage (ICH) is a devastating subtype of stroke with high morbidity and mortality. However, there is no effective therapy method to improve its clinical outcomes to date. Here we report an injectable gelatin hydrogel that is capable of suppressing inflammation and enhancing functional recovery in a mouse model of ICH. Thiolated gelatin was synthesized by EDC chemistry and then the hydrogel was formed through Michael addition reaction between the thiolated gelatin and polyethylene glycol diacrylate. The hydrogel was characterized by scanning electron microscopy, porosity, rheology, and cytotoxicity before evaluating in a mouse model of ICH. The in vivo study showed that the hydrogel injection into the ICH lesion reduced the neuron loss, attenuated the neurological deficit post-operation, and decreased the activation of the microglia/macrophages and astrocytes. More importantly, the pro-inflammatory M1 microglia/macrophages polarization was suppressed while the anti-inflammatory M2 phenotype was promoted after the hydrogel injection. Besides, the hydrogel injection reduced the release of inflammatory cytokines (IL-1β and TNF-α). Moreover, integrin β1 was confirmed up-regulated around the lesion that is positively correlated with the M2 microglia/macrophages. The related mechanism was proposed and discussed. Taken together, the injectable gelatin hydrogel suppressed the inflammation which might contribute to enhance the functional recovery of the ICH mouse, making it a promising application in the clinic.

Based on the correction factor of accuracy applied in ISO standard 3408-4:2006, this article proposed a modified method to calculate the effective ball number and basic static load rating of ball screws. Meanwhile, the basic static load rating of ball screws was obtained through a new measurement method presented in this article. The experimental results, agreeing well with the theoretical values calculated by the modified method, showed that there is a large discrepancy between the basic static load rating calculated by the traditional method and the measured result, which proves that the new modified method is valid. This study provides a more accurate method to obtain the basic static load of ball screws, which is significant for predicting the performance and service life of ball screws.

With the development of rolling linear guide manufacturing, improvements of performance and reliability of rolling linear guide products have become the critical technical challenge. One of the key-points lies in the analysis of wear process, in which the crucial step depends on the computation of the wear coefficient. However, little attention has been devoted to the wear coefficient of rolling linear guide. Therefore, in this article, to reflect the actual working condition of rolling linear guide, a novel calculation model for the wear coefficient of rolling linear guide is established first through theoretical analysis. And then, based on a novel loading bench and a friction measuring device, the wear process and wear coefficients of a rolling linear guide (DA45CL) were obtained and analyzed. Further analysis shows that the wear coefficients obtained in this article, which are several orders of magnitude less than the previous empirical values, are more reasonable for the wear analysis of rolling linear guide. The current work provides a new theoretical and experimental method to investigate the wear coefficient for rolling linear guide, which is meaningful for the study of the wear process of rolling linear guide and other rolling components of computer numerical control (CNC) machine tools.

This article aims to investigate the fluctuation of the static rigidity for preloaded ball screws. Based on the correlation between preload and friction torque, a new model to calculate the contact rigidity by friction torque is proposed. Meanwhile, a novel test bench is constructed to measure the static stiffness at different positions. The experimental results agree well with the theoretical values, which proves the validity of the model. Furthermore, it is found that the screw shaft rigidity has the greatest influence on the system stiffness fluctuation, compared to the bearing rigidity, and the torsional rigidity. For the feed system, increasing the bearing rigidity, which is the lowest stiffness of the whole system, is an effective method to increase the system stiffness. The study provides an accurate method to obtain the stiffness fluctuation in the effective travel of ball screws, which is significant for improving the positioning accuracy of ball screws and computer numerical control machine tools.

This article establishes an axial contact stiffness model of position preloaded ball screw mechanism based on Hertz contact theory. The analysis of dynamic axial contact stiffness is one of the foundations of the research on the dynamic characteristic of the ball screw feed drive system. The model takes into account the coupling relationship between the contact angle and the normal contact force, as well as the coupling relationship between the elastic deformation and the contact deformation coefficient. The static and dynamic axial contact stiffness characteristics of the preloaded ball screw mechanism are studied. The numerical analysis result shows that the static contact stiffness of the preloaded ball screw mechanism increases with the increase in the preload and decreases with the increase in the axial load. The dynamic contact stiffness of the preloaded ball screw mechanism increases with the increase in the screw’s rotational speed. The variation range of dynamic contact stiffness increases with the increase in axial load under the same preload. And the variation range of dynamic contact stiffness decreases with the increase in preload under the same axial load. The axial contact stiffness model established in this article can be used to analyze either static or dynamic contact stiffness of position preloaded ball screw mechanism.

Based on the empirical equations for the friction torque of rolling bearings, this article proposes a new model for predicting the friction torque and mechanical efficiency of ball screws. Meanwhile, a novel measuring system is constructed to obtain the mechanical efficiency of ball screws, where both the axial load and rotational speed are stable and adjustable. The experimental results at a rotational speed of 1000 r/min agree well with the theoretical values calculated by the present method, which show that the mechanical efficiency of ball screws increases with increasing axial load. Moreover, the model built in this article is more applicable to a relatively high-speed condition. The new model can be easily used to obtain the friction torque and mechanical efficiency for ball screws, which is essential for improving the performance of ball screws and the computer numerical control machine tools.

This article presents an experimental investigation into the damping characteristics of a linear damper with a newly designed oil groove. The damping performance of the damper is tested in four different viscosity grades by the sweep frequency method. And a test bench is used to move the damper for a several kilometers to examine the damping maintenance. The experimental results show that a higher oil viscosity leads to a higher damping capacity of the linear damper, and the increase in the oil viscosity will improve the damping maintenance of the damper. The newly designed oil groove efficiently improved the damping capacity of the linear damper; a proper oil selection will further optimize the effect of the oil groove via minimizing the oil leakage.

This article reports a compact wideband piezoelectric vibration energy harvester consisting of three proof masses and an asymmetric M-shaped cantilever. The M-shaped beam comprises a main beam and two folded and dimension varied auxiliary beams interconnected through the proof mass at the end of the main cantilever. Such an arrangement constitutes a three degree-of-freedom vibrating body, which can tune the resonant frequencies of its first three orders close enough to obtain a utility wide bandwidth. The finite element simulation results and the experimental results are well matched. The operation bandwidth comprises three adjacent voltage peaks on account of the frequency interval shortening mechanism. The result shows that the proposed piezoelectric energy harvester could be efficient and adaptive in practical vibration circumstance based on multiple resonant modes.

Aiming at the functional requirement of climbing up the stairs, the dynamics and stability during a tracked mobile robot's climbing of stairs is studied. First, from the analysis of its cross-country performance, the mechanical structure of the tracked mobile robot is designed and the hardware composition of its control system is given. Second, based on the analysis to its stairs-climbing process, the dynamical model of stairs-climbing is established by using the classical mechanics method. Next, the stability conditions for its stairs-climbing are determined and an evaluation method of its stairs-climbing stability is proposed, based on a mechanics analysis on the robot's backwards tumbling during the stairs-climbing process. Through simulation and experiments, the effectiveness of the dynamical model and the stability evaluation method of the tracked mobile robot in stairs-climbing is verified, which can provide design and analysis foundations for the tracked mobile robots' stairs-climbing.

Purpose: To investigate the factors affecting footplate position and its influence on vault characteristics after implantable collamer lens (ICL) implantation. Setting: Hunan Provincial People's Hospital, Changsha, China. Design: Retrospective case series. Methods: This study included 124 patients (124 eyes). Ultrasound biomicroscopy (UBM) was performed to assess the iris and ciliary body morphologies and observe the footplate position. Using multiple linear regression, the relationship between various ocular and ICL parameters and the vault as well as the factors affecting the footplate distance (FD) were analyzed. Based on the FD, 3 groups were formed: group 1 (<500 mm), group 2 (500 to 1000 mm), and group 3 (>1000 mm). The distribution of the vault range postoperatively was observed for the 3 groups. Results: Ciliary sulcus angle and FD significantly affected the vault (adjusted R² = 0.190, F = 6.763, P < .001), with FD being the most important factor influencing the vault (b = -0.383, P < .001). Postoperative UBM revealed that the footplate was located at different positions in the posterior chamber, with the majority (52%) being located on the ciliary body. The mean size of the 4 footplate orientations was 0.88 ± 0.24 mm. Multiple linear regression analysis revealed that ciliary body thickness (CBT), iris curvature (IC), and ICL iris contact length (IRCL) significantly influenced the FD (adjusted R² = 0.373, F = 11.432, P < .001). The vault range differed significantly among the 3 groups (X² = 32.33, P < .001). Conclusions: Different postoperative ICL footplate positions significantly affect the vault. CBT, IC, and IRCL can alter the position of the footplate from the expected position. This study provides reference for ICL size selection and vault prediction. [ABSTRACT FROM AUTHOR]

Structural and functional connectomes are emerging as important instruments in the study of normal brain function and in the development of new biomarkers for a variety of brain disorders. In contrast to single-network studies that presently dominate the (non-connectome) network literature, connectome analyses typically examine groups of empirical networks and then compare these against standard (stochastic) network models. The current practice in connectome studies is to employ stochastic network models derived from social science and engineering contexts as the basis for the comparison. However, these are not necessarily best suited for the analysis of connectomes, which often contain groups of very closely related networks, such as occurs with a set of controls or a set of patients with a specific disorder. This paper studies important extensions of standard stochastic models that make them better adapted for analysis of connectomes, and develops new statistical fitting methodologies that account for inter-subject variations. The extensions explicitly incorporate geometric information about a network based on distances and inter/intra hemispherical asymmetries (to supplement ordinary degree-distribution information), and utilize a stochastic choice of network density levels (for fixed threshold networks) to better capture the variance in average connectivity among subjects. The new statistical tools introduced here allow one to compare groups of networks by matching both their average characteristics and the variations among them. A notable finding is that connectomes have high "smallworldness" beyond that arising from geometric and degree considerations alone.

Ulva, an edible green alga, contains sulfated polysaccharides and oligosaccharides that possess immunomodulatory and anti-inflammatory properties. The objective of this study was to investigate the anti-allergic effects of Ulva-derived samples of polysaccharides (UP), oligosaccharides (UO), and residues (UR) on delayed-type hypersensitivity (DTH) in mice. Oral treatment of mice with UP, UO, and UR (250 mg/kg body weight) daily noticeably improved the DTH reaction as evidenced by attenuation of footpad swelling and cell infiltration at the allergen-challenge site. Although the Ulva samples had limited impacts on the production of serum total IgG, decreased concentrations of allergen-specific IgG and IgG2a and an increased concentration of IgG1 were observed in the treated mice. Moreover, treatment with them suppressed allergen-induced IFN-γ and TNF-α secretion and elevated IL-4 secretion. However, none of the Ulva sample treatments could modulate the production of IL-10. Concordantly, the in situ data reveal that the Ulva sample treatments suppressed IFN-γ and TNF-α expression at the allergen-injection site. These findings collectively suggest the potential of UP, UO, and UR as functional food candidates for the management of delayed-type hypersensitivity. [ABSTRACT FROM AUTHOR]

The corpus callosum is the largest white matter fiber bundle connecting the two cerebral hemispheres. In this work, we investigate the effect of callosal dysgenesis on functional magnetic resonance imaging (fMRI) resting-state networks and the functional connectome. Since alternate commissural routes between the cerebral hemispheres exist, we hypothesize that bilateral cortical networks can still be maintained in partial or even complete agenesis of the corpus callosum (AgCC). However, since these commissural routes are frequently indirect, requiring polysynaptic pathways, we hypothesize that quantitative measurements of interhemispheric functional connectivity in bilateral networks will be reduced in AgCC compared with matched controls, especially in the most highly interconnected cortical regions that are the hubs of the connectome. Seventeen resting-state networks were extracted from fMRI of 11 subjects with partial or complete AgCC and 11 matched controls. The results show that the qualitative organization of resting-state networks is very similar between controls and AgCC. However, interhemispheric functional connectivity of precuneus, posterior cingulate cortex, and insular-opercular regions was significantly reduced in AgCC. The preserved network organization was confirmed with a connectomic analysis of the resting-state fMRI data, showing five functional modules that are largely consistent across the control and AgCC groups. Hence, the reduction or even complete absence of callosal connectivity does not affect the qualitative organization of bilateral resting-state networks or the modular organization of the functional connectome, although quantitatively reduced functional connectivity can be demonstrated by measurements within bilateral cortical hubs, supporting the hypothesis that indirect polysynaptic pathways are utilized to preserve interhemispheric temporal synchrony.

Adopting a network perspective, the structural connectome reveals the large-scale white matter connectivity of the human brain, yielding insights into cerebral organization otherwise inaccessible to researchers and clinicians. Connectomics has great potential for elucidating abnormal connectivity in congenital brain malformations, especially axonal pathfinding disorders. Agenesis of the corpus callosum (AgCC) is one of the most common brain malformations and can also be considered a prototypical genetic disorder of axonal guidance in humans. In this exploratory study, the structural connectome of AgCC is mapped and compared to that of the normal human brain. Multiple levels of granularity of the AgCC connectome are investigated, including summary network metrics, modularity analysis, and network consistency measures, with comparison to the normal structural connectome after simulated removal of all callosal connections ("virtual callostomy"). These investigations reveal four major findings. First, global connectivity is abnormally reduced in AgCC, but local connectivity is increased. Second, the network topology of AgCC is more variable than that of the normal human connectome, contradicting the predictions of the virtual callostomy model. Third, modularity analysis reveals that many of the tracts that comprise the structural core of the cerebral cortex have relatively weak connectivity in AgCC, especially the cingulate bundles bilaterally. Finally, virtual lesions of the Probst bundles in the AgCC connectome demonstrate that there is consistency across subjects in many of the connections generated by these ectopic white matter tracts, and that they are a mixture of cortical and subcortical fibers. These results go beyond prior diffusion tractography studies to provide a systems-level perspective on anomalous connectivity in AgCC. Furthermore, this work offers a proof of principle for the utility of the connectome framework in neurodevelopmental disorders.