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It is proposed to achieve high beam quality 1 064 nm laser output by using an 878.6 nm LD end-pumped Nd: YVO4 crystal. Matlab software is utilized for simulating and analyzing the thermal lens focal length of the crystal, and an appropriate plano-convex resonator cavity configuration is selected through software calculation to alleviate thermal effects and achieve optimal output conditions. At a pump power of 48 W, an average output power of 15.03 W of 1 064 nm continuous light output is obtained. By employing RTP electro-optic Q-switching, stable 1 064 nm pulsed laser output is achieved at a repetition rate of 10 kHz, with a maximum average output power of 8.78 W, a dynamic-to-static conversion efficiency of 72.9%, a pulse width of 8.70 ns, and a beam quality factor of 1.2. The experiments demonstrate that using a pump source at 878.6 nm and employing a flat-convex resonator cavity configuration are beneficial for mitigating crystal thermal effects, improving beam quality, and obtaining fundamental mode pulsed laser output. [ABSTRACT FROM AUTHOR]

During the operation of rack railway on super-slope bridges (especially under temperature load), structural deformation of bridge-end is much larger than that of rack due to the difference of structural continuity between bridge and rack, which greatly increases local stress in rack, damages rack and fastener, and seriously threatens the operation reliability. To investigate the reliability of rack caused by temperature load and nonlinear dynamic interaction between super-slope bridge and rack, a detailed vehicle-rack(rail)-bridge coupled dynamic model is established with consideration of nonlinear dynamic meshing behaviour of gear-rack system and nonlinear dynamic contact behaviour of wheel-rail system. Then a field test is performed to obtain the basis dynamic behaviour of rack railway and validate the established numerical model. On this basis, the effects of temperature load, gear-rack meshing behaviour and wheel-rail contact behaviour on deformation and internal stress of rack-bridge system are investigated. Finally, the method to guarantee the structural reliability of rack railway on super-slope bridge is proposed. Results show that rack deformation nearby bridge gap is highly inconsistent with bridge deformation subject to different loads, and the internal stresses in rack and bolt exceed limit values written in relevant code, which seriously threatens the reliability of the rack structure. The maximum rack stress is 898 MPa, which exceeds the tensile strength of rack. The maximum shear stresses of bolts between fastener and rack and between fastener and sleeper are 1510 MPa and 656 MPa respectively, which exceed the shear strength of bolts. According to the calculation results in this paper, elastic fastener is suggested to be used to connect rack and sleeper, which can effectively reduce stress in rack and bolt, and improve the reliability of the rack structure. [ABSTRACT FROM AUTHOR]

Axial compression tests were conducted on short rhombic tubes of different cross-sectional shapes. The deformation modes of the rhombic short tubes were obtained. To induce a finite element model with deformation modes consistent with the actual working conditions, buckling modes are introduced into the model as the initial imperfections of the structure. However, the buckling modes resulting from finite element buckling analyses often do not meet the needs of actual crushing modes. A coefficient superposition method of solution is proposed to derive modal characteristics consistent with the actual deformation modes by linear superposition of the buckling modes. Through the study of three aspects of theory, test, and simulation, and the comparison and verification of this method with the simulation results of related literature, the results show that the indexes derived from this method are closer to the actual circumstances and are more expandable, which provides a reference for the project. [ABSTRACT FROM AUTHOR]

Aims/Background Hematospermia, characterized by blood in the ejaculate, is a common and distressing condition in urology. Identifying the underlying causes, including translucent membranes in the prostatic utricle, is crucial for effective management. Despite advancements in diagnostic techniques, reliable predictive tools are needed to enhance preoperative planning and patient outcomes. This study aimed to develop a novel nomogram to predict the presence of translucent membranes in the prostatic utricle of hematospermia patients. Methods In total, 284 patients were selected from The Second People's Hospital of Hefei database based on inclusion and exclusion criteria. The cohort was divided into a training set (198 patients) and a validation set (86 patients). To identify risk factors associated with the prostatic utricle translucent membrane, multivariable logistic regression analysis was employed. The identified risk factors were then used to construct a predictive nomogram model. The performance of the nomogram was evaluated using several statistical tools: receiver operating characteristic (ROC) curves to assess discriminative ability, calibration curves to evaluate prediction accuracy, and decision curve analysis (DCA) to determine clinical utility. Results The findings revealed that age, duration of disease, history of seminal vesiculitis, and seminal vesicle dimensions (width, length, and thickness) were independent risk factors for the presence of a prostatic utricle translucent membrane in patients with hematospermia. Using these variables, a nomogram was developed. The nomogram demonstrated strong predictive capability, as evidenced by its performance in ROC and calibration curve analyses. Furthermore, the DCA indicated that the nomogram offered significant clinical net benefits in predicting the presence of a translucent membrane. Conclusion Clinical use of the developed nomogram can assist clinicians in identifying patients with hematospermia who have translucent membrane in the prostatic utricle and in developing individualized treatment. [ABSTRACT FROM AUTHOR]

Summary: In this study, six groups of carrots were designed and fermented using Weissella paramensenteroides MbWp142 (WP), Levilactobacillus brevis GDMCC 1.773 (LS), Leuconostoc mesenteroides GDMCC 1.774 (SE), mixed fermentation of three lactic acid bacteria (WP + LS + SE), pasteurisation group (BG) and natural fermentation group (CK). GC–MS results indicated that inoculation of WP + LS + SE increased the types and contents of flavour substances such as alcohols, esters and hydrocarbons. Compared with other experimental groups, the peak nitrite value in the LS group was lower due to the production of organic acids by lactic acid bacteria. Sensory evaluation revealed that the quality and flavour of carrot fermented by LS were superior to those fermented by SE, WP and WP + LS + SE. Therefore, Levilactobacillus brevis used as a starter for fermenting carrot can enhance product quality and reduce nitrite accumulation during fermentation. [ABSTRACT FROM AUTHOR]

Summary: Meat is widely regarded as the optimal source of protein for human consumption. However, meat is susceptible to spoilage and microbial contamination throughout processing, transportation and storage stages. Traditional thermal processing techniques are commonly employed in the global meat industry. While these methods ensure microbiological safety, they may also impact the sensory and functional attributes of meat products. To address these limitations, non‐thermal processing technologies are progressively replacing conventional thermal approaches. This review will primarily focus on the potential application of non‐thermal processing technologies as alternatives to traditional methods in meat and meat product processing. Various technologies exhibiting promising performance in this field will be presented. Additionally, the mechanisms, advantages and limitations of these non‐thermal technologies in recent years will be summarised, along with a discussion on the challenges and prospects they present. This study provides an overview of non‐thermal processing technology specifically applied to meat products, emphasising the underlying mechanisms associated with different approaches. By employing diverse technical combinations, it is possible to address existing processing limitations and expand their applicability range. Non‐thermal processing technology demonstrates significant potential for enhancing meat processing practices; however, concerns regarding safety aspects and limited clinical verification about to environmental pollution have impeded its widespread adoption within the food industry. [ABSTRACT FROM AUTHOR]