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Abstract Polycystic ovary syndrome (PCOS) is among the most prevalent endocrine and metabolic disorders affecting women of reproductive age. Multiple factors, including genetic predisposition, environmental influences, and lifestyle choices, are considered significant contributors to the development of PCOS. A kind of long noncoding RNA—C-Terminal binding protein 1 antisense (lncRNA CTBP1-AS) has been proven to be a new androgen receptor regulator. Previous studies showed that the lncRNA CTBP1-AS gene was highly expressed in a small sample of PCOS patients and was associated with the risk of PCOS, but its specific function and mechanism have not been clearly reported. In this study, the expression of lncRNA CTBP1-AS was detected by real-time quantitative PCR (RT-qPCR) in PCOS patients. In addition, lncRNA CTBP1-AS was overexpressed in KGN cells to explore its effect on granulocyte function. The results showed that the expression levels of lncRNA CTBP1-AS were increased in peripheral blood mononuclear cells and follicular fluid granulosa cells of PCOS patients compared with controls, which correlated with androgen levels and sinus follicle number; overexpression of lncRNA CTBP1-AS increased apoptosis and decreased cell migration ability, thus promoting the progression of PCOS. This study explores new biomarkers and therapeutic targets for the clinical individualized diagnosis and treatment of PCOS.

To evaluate the degree of unsaturation of different varieties of Camellia oil, it was necessary to establish a rapid evaluation method with a narrow iodine value range (iodine value difference less than 10). In this study, a rapid quantitative prediction model for iodine value of oil in high-resolution Raman spectroscopy based on linear regression and gradient descent method was established. The Raman signals (785 nm) about 39 group of Camellia oil samples and 10 group of commercially oils were firstly collected. Then, the intensity ratio of peaks of 1656 cm−1 and 1440 cm−1 (I1656/1440) were selected through smoothing algorithm least squares smoothing filter (Savitzky-Golay), polynomial fitting and deconvolution algorithm Lorentzian. A credible model was obtained through correlation analysis with the iodine value of corresponding oil samples. The coefficient of determination (R2) of the test set of the constructed quantitative model was >0.82, the mean square error (MSE) was

Objective As the design speed of trains reaches 400 km/h level, the flow field environment under the train becomes more complex, highlighting the issues such as increased brake disc resistance and power consumption. It is imperative to conduct in-depth research on the optimal arrangement spacing of train brake disc heat dissipation ribs at this speed level. Method Using a cylindrical heat dissipation rib structure as the basis, a model is established through finite element simulation, inputting relevant parameter values. Four calculation conditions are set for the center-to-center distance (dc) circumferentially between adjacent heat dissipation ribs, and five calculation conditions are set radially for the distance (dr) between adjacent heat dissipation ribs. Various dc and dr values are calculated respectively for their impact on brake disc temperature rise, resistance, and heat dissipation power. It is aimed to determine recommended values for both dc and dr. Result & Conclusion When dr equals 40 mm (i.e. the ratio of the distance between the heat dissipation ribs and the brake disc edge to the brake disc diameter is 0.75), the brake disc temperature rise reaches the lowest value, indicating the optimal performance of brake disc. For heat dissipation ribs with a diameter equal to half of dc, the brake disc demonstrates the best overall performance.

Purpose – In response to the problem of insufficient traction/braking adhesion force caused by the existence of the third-body medium on the rail surface, this study aims to analyze the utilization of wheel-rail adhesion coefficient under different medium conditions and propose relevant measures for reasonable and optimized utilization of adhesion to ensure the traction/braking performance and operation safety of trains. Design/methodology/approach – Based on the PLS-160 wheel-rail adhesion simulation test rig, the study investigates the variation patterns of maximum utilized adhesion characteristics on the rail surface under different conditions of small creepage and large slip. Through statistical analysis of multiple sets of experimental data, the statistical distribution patterns of maximum utilized adhesion on the rail surface are obtained, and a method for analyzing wheel-rail adhesion redundancy based on normal distribution is proposed. The study analyzes the utilization of traction/braking adhesion, as well as adhesion redundancy, for different medium under small creepage and large slip conditions. Based on these findings, relevant measures for the reasonable and optimized utilization of adhesion are derived. Findings – When the third-body medium exists on the rail surface, the train should adopt the low-level service braking to avoid the braking skidding by extending the braking distance. Compared with the current adhesion control strategy of small creepage, adopting appropriate strategies to control the train’s adhesion coefficient near the second peak point of the adhesion coefficient-slip ratio curve in large slip can effectively improve the traction/braking adhesion redundancy and the upper limit of adhesion utilization, thereby ensuring the traction/braking performance and operation safety of the train. Originality/value – Most existing studies focus on the wheel-rail adhesion coefficient values and variation patterns under different medium conditions, without considering whether the rail surface with different medium can provide sufficient traction/braking utilized adhesion coefficient for the train. Therefore, there is a risk of traction overspeeding/braking skidding. This study analyzes whether the rail surface with different medium can provide sufficient traction/braking utilized adhesion coefficient for the train and whether there is redundancy. Based on these findings, relevant measures for the reasonable and optimized utilization of adhesion are derived to further ensure operation safety of the train.

Abstract Background Animal experiments have confirmed that remote ischemic preconditioning (RIPC) can reduce hepatic ischemia-reperfusion injuries (HIRIs), significantly improving early tissue perfusion and oxygenation of the residual liver after resections, accelerating surgical prognoses, and improving survival rates. However, there is still controversy over the role of RIPC in relieving HIRI in clinical studies, which warrants clarification. This study aimed to evaluate the beneficial effects and applicability of RIPC in hepatectomy and to provide evidence-based information for clinical decision-making. Methods Randomized controlled trials (RCTs) evaluating the efficacy and safety of RIPC interventions were collected, comparing RIPC to no preconditioning in patients undergoing hepatectomies. This search spanned from database inception to January 2024. Data were extracted independently by two researchers according to the PRISMA guidelines. The primary outcomes assessed were postoperative alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBIL), and albumin (ALB) levels. The secondary outcomes assessed included duration of surgery and Pringle, length of postoperative hospital stay, intraoperative blood loss and transfusion, indocyanine green (ICG) clearance, hepatocyte apoptosis index, postoperative complications, and others. Results Ten RCTs were included in this meta-analysis, with a total of 865 patients (428 in the RIPC group and 437 in the control group). ALT levels in the RIPC group were lower than those in the control group on postoperative day (POD) 1 (WMD = − 59.24, 95% CI: − 115.04 to − 3.45; P = 0.04) and POD 3 (WMD = − 27.47, 95% CI: − 52.26 to − 2.68; P = 0.03). However, heterogeneities were significant (I 2 = 89% and I 2 = 78%), and ALT levels on POD 3 were unstable based on a sensitivity analysis. AST levels on POD 1 in the RIPC group were lower than those in the control group (WMD = − 50.03, 95% CI: - 94.35 to − 5.71; P = 0.03), but heterogeneity was also significant (I 2 = 81%). A subgroup analysis showed no significant differences in ALT and AST levels on POD 1 between groups, regardless of whether the Pringle maneuver or propofol was used for anesthesia (induction only or induction and maintenance, P > 0.05). The remaining outcome indicators were not statistically significant or could not be analyzed due to lack of sufficient data. Conclusion RIPC has some short-term liver protective effects on HIRIs during hepatectomies. However, there is still insufficient evidence to encourage its routine use to improve clinical outcomes. Trial registration The protocol of this study was registered with PROSPERO (CRD42022333383).

Bacillus anthracis is a Gram-positive bacterium that can cause acute infection and anthracnose, which is a serious concern for human health. Determining Bacillus anthracis through its spore biomarker dipicolinic acid (DPA) is crucial, and there is a strong need for a method that is rapid, sensitive, and selective. Here, we created Eu(III)-coordination polymers (Eu-CPs) with surfaces that have abundant carboxyl and hydroxyl groups. This was achieved by using citric acid and europium nitrate hexahydrate as precursors in a straightforward one-pot hydrothermal process. These Eu-CPs were then successfully utilized for highly sensitive DPA determination. The fluorescence (FL) emission of Eu-CPs, which is typically weak due to the coordination of Eu(III) with water molecules, was significantly enhanced in the presence of DPA. This enhancement is attributed to the competitive binding between DPA’s carboxyl or hydroxyl groups and water molecules. As a result, the absorbed energy of DPA, when excited by 280 nm ultraviolet light, is transferred to Eu-CPs through an antenna effect. This leads to the emission of the characteristic red fluorescence of Eu3+ at 618 nm. A strong linear relationship was observed between the enhanced FL intensity and DPA concentration in the range of 0.5–80 μM. This relationship allowed for a limit of detection (LOD) of 15.23 nM. Furthermore, the Eu-CPs we constructed can effectively monitor the release of DPA from Bacillus subtilis spores, thereby further demonstrating the potential significance of this strategy in the monitoring and management of anthrax risk. This highlights the novelty of this approach in practical applications, provides a valuable determination technique for Bacillus anthracis, and offers insights into the development cycle of microorganisms.

Abstract A series of terpenoids (1–17), comprising six new compounds designated bipolariterpenes A-F (1–6) and eleven recognized compounds (7–17), were isolated from the wheat culture of the potato endophytic fungus Bipolaris eleusines. Their structures and stereochemistry were clarified by HRESIMS, NMR, DP4 + probability analyses, and computations for electronic circular dichroism (ECD). All compounds are made up of six meroterpenoids, four sesterterpenes and seven sesquiterpenes. Among them, four sesterterpenes (4, 5, 10, 11) were investigated for their antifungal, antibacterial and cytotoxic properties, and six meroterpenoids (1–3, 7–9) were evaluated for their antifungal properties. The compounds 7, 9, and 10 had substantial antifungal activity against Epidermophyton floccosum at a concentration of 100 µM. No antibacterial and cytotoxic activities were observed. Graphical Abstract

The unique properties of silicon nanotubes (SiNTs) are expected to provide them with a very wide range of application potential in nanoelectronic devices, lithium-ion batteries, sensors, field-effect transistors, magnetic nanodevices, hydrogen reservoirs, optoelectronic devices, field emission display devices, and quantum computers, and they are a new one-dimensional nanomaterial with a wide range of applications in the future. Although researchers have already prepared SiNTs in the laboratory, there are not many research reports on SiNTs, especially the preparation of B and P doped SiNTs and analysis based on spectroscopic techniques. Our research group used silicon sources (SiO2 and Si) that had not been previously reported or catalyzed by the rare earth element lanthanum (La). The optimal experimental conditions for the preparation of SiNTs, as well as the doping preparation and study of B and P, were explored by thermal evaporation. Finally, SEM, Raman spectroscopy, selected area electron diffraction, HRTEM, XRD, PL spectroscopy, and other characterization methods were performed on the experimental samples. The experimental results show that 1280 °C was the best experimental temperature for the preparation of SiNTs. Under experimental conditions of 1280 °C, doping of B favored the synthesis of silicon nanowires and SiNTs, and the number of products generated was from least to most: no added B2O3 < 0.1 g B2O3 < 0.2 g B2O3 < 0.3 g B2O3 < 0.4 g B2O3. Under the experimental conditions of 1280 °C, when the amount of doped B2O3 is large (2.2 g), a “needle” structure product is generated. Under experimental conditions of 1400 °C, when the ratio of doped P to the original material is 1:9, a new material that has not been previously reported is generated. Through relevant research and the findings of this paper, it is hoped that it can be helpful for the future research and application of SiNTs.

The electro-mechanical brake is a new advancement in railway train braking. Ball-screws are important components of electro-mechanical braking units (EMBUs), and their wear can cause EMBUs to degrade in performance or even fail to function. In this paper, we present a framework for prediction of ball-screw wear with discrete operating conditions as inputs, taking into account the time-varying characteristics of EMBUs. The framework includes determining the contact type, analyzing relative motion, calculating contact deformations, and estimating wear. The contact type is determined based on the quasi-static approach of Hertz theory. A dynamics model using multiple coordinate systems is established to analyze how balls and raceways move in relation to each other. The contact deformations of the ball–raceway contact are determined using numerical calculation. Then, the wear depth increment is calculated using the Archard model. The results of the calculation and the endurance test indicate that the wear on the screw raceway is greater than that on the nut raceway. The effect of velocity is greater than the effect of axial force. The presented calculation framework is reasonable and can be used for predicting EMBU ball-screw wear.

The wheel slide protection control system for rail vehicles plays a crucial role in ensuring a consistent braking performance in all operating environments, making it a vital factor in the safety and efficiency of rail transportation. In this paper, a hybrid approach to wheel slide protection control is presented, which combines the rule-based control strategy and the model-based control methods using adhesion force estimation. Model-based control usually relies on mathematical models to characterize the vehicle dynamics, requiring online estimators to be designed or extra sensors to be added for practical application. Rule-based control operates on predefined rules and thresholds and the available data from vehicles in service. A comparative test was conducted between the traditional rule-based control strategy and the proposed combined control strategy using a semi-physical simulation test bench. The performance differences of the control strategies were analyzed from two perspectives: adhesion utilization and air consumption. It was observed that among the traditional 2-phase, 3-phase, 4-phase and the optimized 4-phase combined control method, the combined control strategy has the best adhesion utilization and the traditional 4-phase control strategy has the least air consumption.

PurposeTo investigate the results of positive antibody to hepatitis surface antigen(anti-HBs)in hospitalized neonates whose mothers were hepatitis B surface antigen (AgHBs) positive and to explore the influencing factors.MethodThe study subjects were hospitalized neonates whose mothers were positive for AgHBs. According to the serological test results of five immune markers of hepatitis B virus (HBV), they were divided into positive for anti-HBs and negative for anti-HBs. Retrospective analysis of relevant factors affecting results of anti-HBs.Result269 cases (80.78%) were positive for anti-HBs and 64 cases (19.22%) were negative for anti-HBs. Univariate analysis results: the number of hepatitis B immunoglobulin (HBIG) injections after birth, whether HBIG was injected within 6 h, whether Hepatitis B vaccine (Hep B) was injected within 6 h, whether combined immunization within 12 h, whether Hep B was vaccinated on time after discharge, whether preterm birth, and whether low birth weight infants were statistically significant (P

In order to further theoretical and experimental research on adhesion recovery, an innovative new test-rig for wheel–rail contact experiments under large slip conditions was developed. The wheel-on-ring category of test-rig was determined to preserve surface conditions on rail. A scale factor of 1/4 and a circling diameter of 2 m were adopted considering the power limit in the laboratory and wheel–rail contact similarity. The test-rig consisting of wheel assemblies, ring track, gearbox, motors and sprinkler system was specially designed for motor decoupling and precise slip control. Then, the accuracy of slip under PID control was verified by simulation and experimental validation. Thereafter, experimental observations with different speeds, axle loads and surface contaminants showed the potential of the new test-rig for exploring adhesion recovery under various surface conditions.

Currently, the theoretical braking force control mode, characterized by actual deceleration as an unstable open-loop output, is the most widely used brake control mode in trains. To overcome the shortcomings of non-deceleration control modes, a deceleration control mode is proposed to realize the closed-loop control of train deceleration. First, a deceleration control algorithm based on parameter estimation was derived. Then, the deceleration control software logic was designed based on the existing braking system to meet the engineering requirements. Finally, the deceleration control algorithm was verified through a ground combination test bench with real brake control equipment and pneumatic brakes. The test results show that the deceleration control can make the actual braking deceleration of the train accurately track the target deceleration in the presence of disturbances, such as uncertain brake pad friction coefficients, line ramps, vehicle loads and braking force feedback errors, as well as their combined effects, and does not affect the original performance of the braking system. The average deceleration in the deceleration control mode is relatively stable, and the control error of instantaneous deceleration is smaller.

Aiming at the problem of low control accuracy caused by nonlinear disturbances in the operation of the PLS-160 wheel–rail adhesion test rig, a linear active disturbance rejection controller (LADRC) suitable for the wheel–rail adhesion test rig was designed. The influence of nonlinear disturbances during the operation of the test rig on the control accuracy was analyzed based on SIMPACK. The SIMAT co-simulation platform was established to verify the control performance of the LADRC designed in this paper. The simulation results show that the speed and creepage errors of the test rig under the control of the LADRC met the adhesion test technical indicators under four different conditions. Compared with the traditional PID controller, the creepage overshoot and response time with the LADRC were reduced by 1.27% and 60%, respectively, under the constant creepage condition, and the stability recovery time was shorter under the condition of a sudden decrease in the adhesion coefficient. The LADRC designed in this paper shows better dynamic and anti-interference performance; therefore, it is more suitable for a follow-up study of the PLS-160 wheel–rail adhesion test rig.

In this paper, we investigate the great potential of the combination of machine learning technology and wireless communications. Currently, many researchers have proposed various optimization algorithms on resource allocation for distributed antenna systems (DASs). However, the existing methods are mostly hard to implement because of their high computational complexity. In this paper, a new system model for machine learning is considered for the scenario of DAS, which is more practical with its low computational complexity. We utilize the k-nearest neighbor (k-NN) algorithm based on the database of a traditional sub-gradient iterative method to get a power allocation scheme for DAS. The simulation results show that our k-NN algorithm can also obtain the power distribution scheme which is very similar to the results of the traditional algorithm.

The unique solution of contractions is a proof technique for bisimilarity that overcomes certain syntactic constraints of Milner's "unique solution of equations" technique. The paper presents an overview of a rather comprehensive formalisation of the core of the theory of CCS in the HOL theorem prover (HOL4), with a focus towards the theory of unique solutions of contractions. (The formalisation consists of about 20,000 lines of proof scripts in Standard ML.) Some refinements of the theory itself are obtained. In particular we remove the constraints on summation, which must be weakly-guarded, by moving to rooted contraction, that is, the coarsest precongruence contained in the contraction preorder.

In the category of drugs approved by the U.S. FDA, pyrrolidine is the most frequently used core of five-membered nonaromatic heterocycles containing nitrogen. Herein, a Rh(II)/Pd(0) dual-catalyzed carbenoid N-H insertion/allylation cascade reaction has been developed. This protocol provide an efficient approach for the construction of diverse highly functionalized and polysubstituted pyrrolidines in high yields (up to 91%) with excellent chemoselectivities and high diastereoselectivities (>20:1) under mild reaction conditions. [ABSTRACT FROM AUTHOR]

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Hydroxylammonium nitrate (HAN; NH3OH+NO3-), a green and non-toxic monopropellant, finds wide application in liquid and controllable solid propulsion. Gel propulsion enjoys advantages such as a high throttling capacity and encouraging operational safety. This study prepared three HAN-based gel propellant samples with gelling agent contents ranging from 2 to 4 wt%. Their decomposition processes were analyzed using thermogravimetry (TG), differential scanning calorimetry (DSC), and mass spectrometry (MS), and a microthruster was designed to investigate their combustion characteristics under varying voltages and flow rates. Results reveal the presence of three exothermic peaks in the HAN-based gel propellants at temperatures of 204, 306 °C and 441 °C. The gel propellants experienced violent decomposition between 100 °C and 400 °C, producing low-molecular-weight organics such as C3H8, C2H6, H2O, O2, and NH3. For the initial ignition, the flow rate exerts a greater effect of reducing the delay time than the voltage. The reignition exhibited a shorter delay time than the initial ignition, and increasing voltage led to a more significant decrease in the reignition delay time than increasing the flow rate. Under a gelling agent content of approximately 4 wt%, the reignition delay time decreased from 2.35 s to 0.65 s as the voltage increased from 150 V to 250 V, with the flame length and light intensity during the reignition greater than those in the initial ignition. At the end of combustion, the extinguishment delay time changed insignificantly under high voltage. As revealed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses, residues with numerous cavities emerged due to incomplete combustion and the severe agglomeration of the gel propellants, exhibiting a maximum chlorine content of up to 77.73%. [ABSTRACT FROM AUTHOR]

A series of poly(ester imide) (PEsI) copolymers were synthesized using 3,3',4,4'-biphenyltetracarboxylic dianhydride (4,4'-BPDA), 2,2'-bis(trifluoromethyl) benzidine (TFMB), and 4-aminophenyl-4'-aminobenzoate (APAB) as the monomers. Wide-angle x-ray diffraction results revealed that the average interchain distances of these polymers ranged from 4.6 to 5.7 Å, increasing with the increase of TFMB contents. PEsI-0.3 and PEsI-0.4 exhibited a glass transition temperature (Tg) of 445 and 455°C, respectively, while no distinctive Tg was observed for the PEsI copolymers when the APAB content was >50 mol%. The coefficients of thermal expansion (CTE) of these PEsI copolymers ranged from 3.8 to 24.2 ppm K-1, increasing with the increase of TFMB contents. The PEsI copolymers exhibited a modulus of 5.7-7.8 GPa, a tensile strength of 282-332 MPa, and an elongation-at-break of 10.2%-23.3%. Furthermore, these copolymers exhibited a dielectric constant of 2.53-2.76, and a low dissipation factor (Df) of 0.0026-0.0032 at 10 GHz in dry state. Because of their excellent combined properties, these PEsI copolymers are promising candidates as dielectric substrate materials for the applications in next generation flexible printed circuit boards operating at high frequencies. [ABSTRACT FROM AUTHOR]

A novel procedure has emerged in recent years within oilfields - namely, the utilization of a hybrid fracturing method employing pre-CO2 injection along with sand-carry slick water. In this paper, based on the real logging data of shale oil reservoirs in the second member of Cangdong Sag, Huanghua Depression, combined with the GOHFER, a coupled 3-D hydraulic fracture propagation model is proposed. This research delves into an examination of how engineering factors exert their influence on the process of fracture propagation. The quantitative analysis is conducted encompassing critical fracture parameters such as half-length, height, and width, and self-defined fracture seepage area and fracture front fractal dimension. The research findings indicate that as injection displacement increases, the fracture shape undergoes a transformation from being "long, low, and wide" to becoming "short, high, and narrow". [ABSTRACT FROM AUTHOR]

Subterranean karst caves are windows into the terrestrial subsurface to deconstruct the dimensions of mycobiome fingerprints. However, impeded by the constraints of remote locations, the inaccessibility of specimens and technical limitations, the mycobiome of subterranean karst caves has remained largely unknown. Weathered rock and sediment samples were collected from Luohandu cave (Guilin, Southern China) and subjected to Illumina Hiseq sequencing of ITS1 genes. A total of 267 known genera and 90 known orders in 15 phyla were revealed in the mycobiomes. Ascomycota dominated all samples, followed by Basidiomycota and Mortierellomycota. The sediments possessed the relatively highest alpha diversity and were significantly different from weathered rocks according to the diversity indices and richness metrics. Fifteen families and eight genera with significant differences were detected in the sediment samples. The Ca/Mg ratio appeared to significantly affect the structure of the mycobiome communities. Ascomycota appeared to exert a controlling influence on the mycobiome co-occurrence network of the sediments, while Ascomycota and Basidiomycota were found to be the main phyla in the mycobiome co-occurrence network of weathered rocks. Our results provide a more comprehensive dimension to the mycobiome fingerprints of Luohandu cave and a new window into the mycobiome communities and the ecology of subterranean karst cave ecosystems. [ABSTRACT FROM AUTHOR]