Explore the vast range of titles available.

Objectives This study aimed to evaluate the effectiveness and feasibility of functional movement screen (FMS) evaluation system and individualized intervention measures in preventing military training injuries. Methods A total of 420 recruits from a unit of the People's Liberation Army of China were included as the research object. According to random grouping method, they were divided into observation group (Group A) and control group (Group B), with 210 patients in each group. Before recruit training, individual FMS was performed, and functional correction training was performed in the observation group according to the test scores, while no intervention measures were applied in the control group. After 3 months of training, the tests were repeated. Age, body mass index (BMI), and incidence of military training injuries were recorded during the training period. Results There was no statistical difference between the two groups in age, BMI, FMS score before the training (P > .05). After receiving functional correction training, the FMS score of the Group A was higher than that of the Group B, and the difference was statistically significant (P < .05). The incidence of military training injury in Group A and Group B was 20.95% and 44.02%, respectively (P < .05), and the difference was statistically significant. Conclusion The evaluation system of FMS and individualized intervention measures are feasible and effective in predicting and reducing the occurrence of military training injuries.

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature. A new type of modified alloy, to be used in automobile engines at high temperatures, was prepared by adding Zr and Mo into Al-Si-Cu-Mg alloy. The synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were studied. Results show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the alloy. They can improve the strength of the alloy by hindering dislocation movement and crack propagation. In addition, some nano-strengthened phases show coherent interfaces with the matrix and improve grain refinement. The addition of Mo greatly improves the heat resistance of the alloy. The extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases, inhibit precipitation during aging, reduce the size of the precipitates, and improve the heat resistance of the alloy.

The application of ultrasonic vibration during the casting process has been proven to refine the microstructure and enhance the properties of the casting. By using the direct inserting method, wherein the ultrasonic horn is inserted directly into the melt, ultrasonic treatment can be utilized in the semi-continuous casting process to produce aluminum ingots with simple shapes. However, due to the attenuation of ultrasound, it is challenging to apply the direct inserting method in the die casting process to produce complex castings. Thus, in this study, the impact of ultrasonic vibration on the microstructure of a gravity die-cast AlSi 9 Cu 3 end cap was investigated by applying ultrasonic vibration on the core (indirect method). It is found that the effect of ultrasonic vibration relies greatly on the resonance mode of the core. Selection of ultrasonic vibration schemes mainly depends on the core structure, and only a strong vibration can significantly refine the microstructure of the casting. For castings with complex structures, an elaborated ultrasonic vibration design is necessary to refine the microstructure of the specified casting. In addition, strong vibration applied on the feeding channel can promote the feeding ability of casting by breaking the dendrites during solidification, and consequently reduce the shrinkage porosity.

The microstructure and corrosion resistance in H2S environments for various zones of X80 pipeline steel submerged arc welded joints were studied. The main microstructures in the base metal (BM), welded metal (WM), coarse-grained heat-affected zone (CGHAZ), and fine-grained heat-affected zone (FGHAZ) were mainly polygonal ferrite and granular bainite; acicular ferrite with fine grains; granular bainite, ferrite, and martensite/austenite constituents, respectively. The corrosion behavior differences resulted from the microstructure gradients. The results of the micro-morphologies of the corrosion product films and the electrochemical corrosion characteristics in H2S environments, including open circuit potential and electrochemical impedance spectroscopy, showed that the order of corrosion resistance was FGHAZ > BM > WM > CGHAZ.

In order to reduce computational complexity and memory requirements using conventional boundary element method (CBEM) for large scale acoustical analysis, a fast solving algorithm called the Fast Multipole BEM (FMBEM) based on the fast multipole algorithm and GMRES iterative solver is developed without composing the dense influence coefficient matrices. The multipole level structure is introduced to accelerate the solution of large-scale acoustical problems, by employing a concept of cells clustering boundary elements and hierarchical cell structure. To further improve the efficiency of the FMBEM with iterative solvers, a block diagonal matrix method is used in the system of equations as the left pre-conditioner. Numerical examples are presented to further demonstrate the efficiency, accuracy and potentials of the fast multipole BEM for solving large-scale acoustical problems.

The determination of the sensitivity of the acoustical characteristics of vibrating systems with respect to the variation of the design parameters can provide a method to low-noise design of mechanical structure objectively and quantitatively. Using the Distributed source energy boundary point method, the expressions of the change of the acoustical energy density with respect to design variable is presented in this paper. The Distributed source energy boundary point method is a speedy and precise method which can avoid the complex computing of the singularity integral in EBEM. The correctness and availability is validated by the numerical simulation.

We report on the simultaneous monitoring of the repeating fast radio burst (FRB) 20240114A at 2.25 and 8.60 GHz, conducted 66 times between 2024 January 29 and 2025 February 15 with the Shanghai Tianma Radio Telescope. In about 180 hr of observation, we detected 155 bursts at 2.25 GHz above a fluence threshold of 0.72 Jy ms but none at 8.60 GHz above a fluence threshold of 0.27 Jy ms. FRB 20240114A exhibited frequency-dependent activity, as evidenced by the nondetections in 14.3 hr of observations at 2.25 GHz prior to 2024 February 24, despite its reported activity below 2 GHz. In contrast to its low-activity state reported below 1.4 GHz between 2024 June and December, FRB 20240114A exhibited high activity at 2.25 GHz in 2024 July with a mean burst rate of 1.72−0.16+0.18hr−1 , followed by a low-activity state. We also detected a short-term reactivation at 2.25 GHz around 2025 January 20, about 2 weeks after renewed activity was reported below 1.4 GHz by other telescopes. The median burst width at 2.25 GHz is 3 ms, which is narrower than that at lower frequencies. The waiting time distribution peaks at 1019 s, and bursts arrive on hourly timescales consistent with a Poisson process. The isotropic-equivalent energy of the bursts spans 1037–1039 erg. The distribution of burst energy above the completeness threshold (7.5 × 1037 erg) follows a power-law relation with an index of γ = −1.20 ± 0.03 ± 0.02. Finally, we find that FRB 20240114A is at least 2 orders of magnitude less active at 8.60 GHz than at 2.25 GHz, and we constrain the broadband spectra of the detected bursts.

Background Hand, foot, and mouth disease (HFMD) is a common infectious disease in childhood caused by an enterovirus (EV), and which is principally seen in children under 5 years of age. To promote diagnostic awareness and effective treatments, to further standardize and strengthen the clinical management and to reduce the mortality of HFMD, the guidelines for diagnosis and treatment have been developed. Methods National Health Commission of China assembled an expert committee for a revision of the guidelines. The committee included 33 members who are specialized in diagnosis and treatment of HFMD. Results Early recognition of severe cases is utmost important in diagnosis and treatment of patients with HFMD. The key to diagnosis and treatment of severe cases lies in the timely and accurate recognition of stages 2 and 3 of HFMD, in order to stop progression to stage 4. Clinicians should particularly pay attention to those EV-A71 cases in children aged less than 3 years, and those with disease duration less than 3 days. The following indicators should alert the clinician of possible deterioration and impending critical disease: (1) persistent hyperthermia; (2) involvement of nervous system; (3) worsening respiratory rate and rhythm; (4) circulatory dysfunction; (5) elevated peripheral WBC count; (6) elevated blood glucose and (7) elevated blood lactic acid. For treatment, most mild cases can be treated as outpatients. Patients should be isolated to avoid cross-infection. Intense treatment modalities should be given for those severe cases. Conclusion The guidelines can provide systematic guidance on the diagnosis and management of HFMD.

Objective This study aimed to characterize the clinical and neuroimaging features of hereditary leptomeningeal transthyretin amyloidosis (hATTR-LA), a dominant inheritance disorder caused by a heterozygous TTR gene mutation. Methods A comprehensive retrospective evaluation was conducted, incorporating detailed clinical records, multimodal neuroimaging findings, and a systematic review of the literature to contextualize the observations. Results The patient was a 55-year-old male who presented with chronic central nervous system symptoms, including sensory-motor peripheral neuropathy and progressive visual impairment. Cerebrospinal fluid analysis revealed elevated protein levels. Neuroimaging showed progressive leptomeningeal hyperdensity on CT and characteristic linear thickening with enhancement of the leptomeninges on MRI, involving both cerebral and spinal regions. Genetic testing confirmed the diagnosis by identifying a heterozygous c.265T > C (p.Y89H) pathogenic variant in exon 3 of the TTR gene, classified as pathogenic according to ACMG guidelines. Conclusion Multimodal imaging provides valuable, non-invasive insights for diagnosing hATTR-LA, enhancing diagnostic accuracy and informing clinical management of this rare condition.