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In this paper, the internal and external cancellation phenomena for damped beams subjected to multi-moving loads are investigated in detail. To start, the theory for the vibration of a simply supported beam is revisited by including the effect of damping. For the first time, a simple expression is derived for the free vibration of the damped beam under multi-moving loads. Based on the concept of local minimum, two cancellation conditions are identified. One is the internal cancellation, which relates to the inherent property of the beam and is conventionally known. The other is the newly formulated external cancellation that relates to the number and spacing of moving loads. For comparison, both the resonant condition and the optimal criterion for span length of the bridge are also briefed. By comparing with the classical solution, the present simple expression for the free vibration of the beam is firstly validated. Then the factors affecting the cancellation are investigated against various load cases and damping levels. The results show that external cancellation occurs more frequently due to the increase in the number and spacing of the moving loads. The damping of the beam has a leaking effect on cancellation, in that nonzero vibration may occur, but it is also quickly damped out by damping itself.

The improvement of the welding speed becomes extraordinarily difficult for the friction stir welding (FSW) of Al–Li alloys with medium thickness (5–10 mm). In this study, 2195-T8 Al alloy plates with a thickness of 6 mm were subjected to FSW under different welding speeds of 200–800 mm/min with the objective of seeking an optimised welding parameter. The tensile strength of ∼422 MPa at a relatively high welding speed of 400 mm/min with a tool rotational speed of 800 rpm was obtained, which reached a comparable level to those of the joints with low welding speeds. The combination of moderate tool rotational speed and moderate welding speed was a feasible optimising direction for FSW of Al–Li alloy with medium thickness.

Dual-function amplifiers are proposed for the first time herein for enhancing the capability of a scanning test vehicle for bridges. To start, closed-form solutions are derived for the dynamic responses of the amplifier-vehicle-bridge system with a moving test vehicle. Then, the dynamic amplification factors of the amplifier and vehicle are presented for assessing the bridge/vehicle and vehicle/amplifier transmissibility. It was known that the spectrum of the vehicle may be hindered for extracting the bridge frequencies because of vehicle frequency and rough pavement. Two differentially tuned amplifiers are called on to tackle the problem: one (i.e., the vehicle damper) is to suppress the effect of vehicle’s frequency, acting like the tuned mass damper (TMD), and the other (i.e., the bridge amplifier) is to enlarge the amplitude of bridge frequency of concern. Based on the parametric study, it is concluded that (1) the bridge amplifier performs better than the vehicle one in extracting bridge frequencies by increasing their visibility in the spectrum; (2) the effect of vehicle’s frequency can be suppressed by tuning the vehicle damper such that it functions like a TMD of the vehicle; (3) by tuning the bridge amplifier to any of the first few bridge frequencies, the latter can be well detected even for rough pavement.

2022年8月欧洲心脏病学会（ESC）年会上发布了“2022年ESC室性心律失常（VA）患者管理及心原性猝死（SCD）预防指南”，基于近年来SCD的流行病学新认识、VA和SCD的危险分层新证据、诊断和治疗方案的新进展等，更新了关于VA管理和SCD预防的推荐。该文主要就新指南结构更新和部分更新内容进行解读。.

Vehicle’s wheels were mostly modeled as a point, which can touch the valleys of pavement roughness, creating unrealistic high-frequency oscillation. This can be avoided by using the disk model for the wheels, which however adds significant complexity to the vehicle–bridge interaction (VBI) analysis. In this paper, a refined roughness formula is generated to account for the wheel size effect such that it can be used by point model. Still, the low-frequency part of the roughness presents some masking effect on the bridge scanning by the test vehicle. To this end, two countermeasures are suggested, i.e. residual response and traffic flows. This study has demonstrated that: (1) the roughness generated by the refined formula can reflect the trace of the disk model; (2) the refined formula facilitates the VBI analysis by using the point model; and (3) the two countermeasures for roughness are effective for improving the scanning of bridge frequencies.

患儿 女，7岁，因“发热、呼吸困难1 d”收入复旦大学附属儿科医院新型冠状病毒重症监护病房，未吸氧下经皮血氧饱和度0.9，呼吸35~45 次/min，影像学两肺散在淡斑片、条片状渗出影，确诊为新型冠状病毒肺炎（重型）。经高流量氧疗和抗感染治疗后病情进行性加重，入院第6天气管插管机械通气，转为危重型，配合纤维支气管镜冲洗、高频胸壁振荡、机械咳嗽辅助设备等气道廓清治疗，患儿病情逐渐好转，有创机械通气治疗第7天后拔除气管插管，入院24 d后病情好转出院。.

新型冠状病毒全球流行下，在儿童专科医院实施有效的常态化管理策略既能保障普通儿科人群的诊疗需求，又能提高既往新型冠状病毒感染和现症感染患儿的救治及时性，同时降低院感发生率。目前，针对儿童新型冠状病毒感染的门、急诊和病房管理措施报道鲜见，本文就新型冠状病毒区域性大流行的情况之下所实施儿童新冠门、急诊-病房一体化管理策略进行实践经验介绍。.

To investigate the epidemiological characteristics and identify the risk factors ofA cross-sectional study was performed for questionnaire surveys among colorectal cancer patients in Henan Cancer Hospital during the period from March to July, 2021. Patients' stool samples were collected, and the triosephosphate isomerase (A total of 307 colorectal cancer patients were investigated, including 176 males (57.3%) and 131 females (42.7%). PCR assay detected 8.1% [95% confidential interval (The prevalence of

2022年4月美国心脏协会（AHA）、美国心脏病学会（ACC）和美国心力衰竭协会（HFSA）联合发布了《2022年AHA/ACC/HFSA心力衰竭管理指南》，旨在为临床医师提供以患者为中心的心力衰竭预防、诊断和管理建议。该文对指南中的10项更新要点进行了解读。.

The vehicle scanning method (VSM), an indirect approach for bridge measurement, has attracted intensive attention since it was proposed by Yang and co-workers in 2004. This method is featured by the fact that no vibration sensors need to be mounted on the bridge, but only one or few vibration sensors are required on the test vehicle. Such an idea has been verified by the field tests, and then quickly extended to construction of mode shapes, identification of damping ratios, and detection of damages for bridges, among others. Compared with the conventional direct method that relies fully on the vibration responses recorded by sensors equipped on the bridge, the advantage of the indirect method is obvious: mobility, economy, and efficiency. Over the years, a rapidly growing number of research works have been conducted along the lines of the VSM for bridge measurement. Particularly, extensive lab experiments and field tests have been carried out worldwide to implement the VSM, resulting in numerous new findings. Moreover, while the technique is still flourishing, it is nourished by inclusion of modern devices such as smartphones, vehicular networks, and cloud. In 2018, a review paper was compiled by two of the authors. To reflect the recent rapid growth of research in this area since then, there exists a need to make an expansion to include the huge number of newly published papers (274 papers in total). As an extension of the 2018 paper, this paper represents a state-of-the-art review of the related researches conducted worldwide. Comments and recommendations will be made at proper places, while concluding remarks including future research directions will be presented at the end of the paper.

本文报道1例继发性甲状旁腺功能亢进术后发生钙化防御的患者。患者女性，43岁，因“维持性血液透析13年余，全身皮肤瘙痒、双下肢疼痛不适3个月”就诊。行甲状旁腺全切+右侧自体旋前圆肌移植术后，予以下肢静脉高浓度补钙，术后第3天患者下肢皮肤出现剧烈疼痛、触觉过敏、网状红斑等问题，经专科医院诊断，排除了钙剂外渗，最终诊断为皮肤钙化防御。.

YUCCA (YUC) proteins are essential for auxin production and play critical roles in plant growth and development. Many of the fourteen rice OsYUCs identified to date have been characterized, but the functions and expression patterns of OsYUC2 remain unclear. In this study, transgenic rice seedlings (Oryza sativa L. ‘Nipponbare’) overexpressing GUS-tagged OsYUC2 under the control of the ubiquitin promoter or the native OsYUC2 promoter were used to investigate OsYUC2 expression and function. OsYUC2 distribution was restricted to rapidly dividing cells in callus, vegetative, and reproductive tissues. OsYUC2 overexpression promoted plant growth, leading to proliferation of embryonic, adventitious, and lateral roots, and increases in shoot height and grain weight. OsYUC2 localization correlated with auxin localization, and auxin content analysis showed that IAA levels were higher in OsYUC2 transgenic rice than in the wild-type. Furthermore, exogenous addition of 3-indolebutyric acid (IBA, an analogue of IAA) in wild-type plants produced growth phenotypes similar to those of OsYUC2 transgenic rice seedlings. Our results indicate that OsYUC2 has distinct expression patterns and regulates major growth and developmental processes in rice.

It is a key to reveal the failure mechanism and constitutive relation of the anchor segment of the anchor cable. By using the self-developed pull-twist coupling device, the pull-out tests for anchor cables with non-rotation and free rotation conditions were carried out, respectively, and the pull-out load–torque–displacement curves were obtained to study the failure mechanism and constitutive relation of the anchor cables. Results show that the pull-out load of the anchor cable with non-rotation is larger than that in the free rotation state, and the torque reverse force generated of the anchor cable accounts for 24.6–32.0% of the pull-out load during the pull-out tests. With the increase in pull-out load, the torque increases firstly and then decreases when it reaches the peak value. The relationships between the pull-out load and torque show the cubic polynomial and are basically linear at different stages. The failure mechanism of the anchorage segment displays the pulling failure at first and then the pulling and shearing failures. The pull-out load–torque–displacement relationship of the anchor cable goes through three stages: the loading, the softening, and the residual stages. The fitted constitutive relationship curves are in good agreement with the experimental curves. The obtained conclusions can provide a theoretical reference for the similar practice.

心房颤动（房颤）患病率高，左心耳封堵预防缺血性卒中近年来有较大进展。成年人卵圆孔未闭（PFO）的发生率较高，PFO与偏头痛及不明原因卒中可能相关，目前指南/专家共识指出，血栓栓塞性脑梗死伴PFO患者，未发现其他卒中发病机制，结合PFO的解剖和分流情况，可考虑PFO封堵术，但对于老年患者并不积极地建议PFO封堵术。对于房颤患者，近年来左心耳联合PFO封堵术在国内外均有报告，但对此类患者的适应证选择及术中和中、远期预后尚不清楚。由于此策略仍存在较多未知和局限性，目前除了患者有明确PFO封堵适应证外，尚无可广泛推荐房颤患者左心耳联合PFO封堵术的证据，仍需要进行进一步研究和评估。.

The plastic forming of titanium alloy tubes at room temperature exhibits strong anisotropy, low elongation, and large deformation resistance. Numerical control warm bending assisted forming technology can improve the stability of the titanium alloy tube bending process, increase the bending limit and reduce the springback angle. This technology promotes the wide application of high-precision titanium alloy bent tubes in many high-end fields such as aerospace, shipbuilding, chemical industry, and military industry. However, the titanium alloy tube bending at high temperatures involves complex material rheological behavior and microstructure characteristics. The coupling relationship between the stress-strain properties of the material and the temperature field makes it difficult to predict the springback behavior of titanium alloy tubes after warm bending. In this paper, based on the mechanical behavior of titanium alloy tubes at high temperatures, a constitutive model of titanium alloy suitable for local heating is improved. The theoretical model of springback for warm rotary draw bending of titanium alloy tube is established. The influence of warm bending strategies on the springback of bending is studied. The theoretical model is verified by establishing a thermal-mechanical coupling finite element model for the whole process of warm bending under the state of heat balance. The results show that the bending springback theory based on the modified John-Cook model can accurately simulate the temperature change of titanium alloy tube section, adapt to local heating strategies and provide high prediction accuracy of bending springback.

Ti45nb is a commonly used titanium alloy with high strength for aviation. However, it is mainly cold formed under conventional conditions and cracks often occur when deformation is large. Ultrasonic vibration-assisted compression test of Ti45Nb titanium alloy was carried out on a universal testing machine equipped with an ultrasonic vibration system. The influence of ultrasonic vibration on the deformation behavior of Ti45Nb was investigated. The results showed that ultrasonic vibration can significantly reduce the flow stress in the deformation process, and the reduction amplitude increases with the continuation of the compression process. The decrease in flow stress is caused by the stress superposition and acoustic softening effect. Compared to the conventional compression test, the grain in the center of the ultrasonic vibration-assisted compressed sample is finer, and the thickness of the lamellar substructure in the shear band is thinner. Therefore, ultrasonic vibration has a promoting effect on the deformation of Ti45Nb alloy.

The material testing machine and the split Hopkinson pressure bar (SHPB) were adopted, respectively, to conduct the static and dynamic compression tests on granite specimens heat treated by...

We investigate a particular regularization of big bang singularity, which remains within the domain of 4-dimensional general relativity but allowing for degenerate metrics. We study the geodesics and geodesic congruences in the modified Friedmann-Lema\^itre-Robertson-Walker universe. In particular, we calculate the expansion of timelike and null geodesic congruences. Based on these results, we also briefly discuss the cosmological singularity theorems., Comment: 16 pages, 1 figure, published version

An analysis of ground deformation of a waterfront perimeter dike and backland fill induced by earthquake shaking is presented. We used the program FLAC, with a bounding surface hypoplasticity model implemented to characterize soil behavior. The input motion for the analysis was derived from a recording obtained at a nearby strong motion station during the 1989 Loma Prieta, California earthquake. Computed pore water pressure and ground displacement are presented and compared with mapped observations.

原发性肝癌是最常见的恶性肿瘤，临床上肝癌中心液化坏死可产生发热症状，其临床症状及影像学特征酷似肝脓肿，易误诊误治。肝脓肿是肝脏的一种感染性疾病，在脓肿形成早期常规超声、影像学等表现往往不典型，难与肝癌鉴别。现介绍1例以腹胀就诊的肝硬化合并肝脓肿的患者，影像学表现可疑肝癌的病例。通过肝病多学科团队协作讨论，明确诊疗方案并随访整个病情的演进过程，希望为临床医生提供新的诊疗思路和模式。.

分析2019年10月以来收治的2例颅底骨髓炎患者的临床资料，2例患者的主要临床症状均为剧烈头痛，颅底MRI均表现为沿组织间隙蔓延的异常信号影。采用内镜经鼻入路手术和抗炎治疗后痊愈，无严重并发症。术后的病理学检查均证实了炎症性病变。.

Recent studies have revealed that long noncoding RNAs (lncRNAs) are dysregulated in malignant tumors and participates in carcinogenesis. The purpose of our study was to uncover the mechanisms underlying lncRNA CASC15 in bladder cancer (BLCA).In this research, Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was performed to detect cancer susceptibility candidate 15 (CASC15) expression in BLCA samples and cells. Besides, the wound healing assay and transwell assay were performed in BLCA cells after CASC15 was knocked down. Furthermore, the bioinformatics analysis and dual-luciferase reporter assay were conducted to explore the target miRNA of CASC15, which was further verified through rescue experiments in BLCA cells.CASC15 expression was upregulated in BLCA tissue samples. Moreover, CASC15 downregulated the miR-130b-3p expression and promoted cell migration and invasion in BLCA in vitro. The rescue experiments also revealed that the inhibitory effects by the silence of CASC15 could be reversed through the inhibition of miR-130b-3p.Our study suggested a vital regulatory mechanism of CASC15 in BLCA, and the CASC15/miR-130b-3p axis might serve as a new therapeutic interventional target for BLCA patients.

Long non-coding RNAs (lncRNAs) have emerged as pivotal participants of various tumors. This manuscript focuses on the function of lncRNA linc01433 (linc01433) in esophageal squamous cell carcinoma (ESCC) development.Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to detect expressions of linc01433 and microRNA-1301 (miR-1301) in ESCC tissues and cells. Cell counting kit-8 (CCK-8) and colony formation assays were used to verify proliferative ability changes in ESCC influenced by linc01433 and miR-1303. Wound healing and transwell assays were chosen to determine migratory ability in ESCC cells.Linc01433 was abnormally up-regulated in ESCC tissues and cells. High level of linc01433 was positively correlated with tumor size and lymph node metastasis in ESCC patients. Up-regulation of linc01433 promoted cell proliferation and migration. MiR-1301 was a potential target of linc01433, and its level was negatively regulated by linc01433. MiR-1301 was responsible for linc01433-regulated proliferation and migration of ESCC.Linc01433 participated in ESCC progression by regulating miR-1301 and it could function as a novel biomarker in ESCC diagnosis and treatment.