bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of Selagibenzophenone A and Its Derivatives for Evaluation of Their Antiproliferative, RORγ Inverse Agonistic, and Antimicrobial Effect**
Authors: Lapinskaite Ringaile , Atalay Hazal Nazlıcan , Malatinec Štefan , Donmez Serhat , Cinar Zeynep Ozlem , Schwarz Patrik F. , Perhal Alexander F. , Císařová Ivana , Labanauskas Linas , Karpiński Tomasz M. , Dirsch Verena M. , Tumer Tugba Boyunegmez , Rycek Lukas
Published: February 2023

We report a modular synthetic approach towards novel derivatives of the naturally occurring arylated benzophenone selagibenzophenone A. The initial strategy for the construction of the carbon framework of the derivatives relied on the Suzuki reaction of 2,4,6‐tribromobenzonitrile, and the addition of the aryl lithium species to nitrile to generate imine. However, the formed imines showed remarkable stability toward hydrolysis. Therefore, Suzuki cross‐coupling was carried out with 2,4,6‐tribromobenzaldehyde and the subsequent addition of organometallic species to the aldehyde. Oxidation of the resulting alcohol ensured the access to desired ketones. The importance of the developed modular strategy is underlined by the discovery of several derivatives with selective cytotoxic effects and potential anti‐inflammatory activity superior to the effect of the natural product.
Alkylboronate β‐Phenylglucoside versus Phenylboronate β‐Alkylglucoside Organogelators
Authors: Ludwig Andreas D. , Gorbunova Viktoriia , Saint‐Jalmes Arnaud , Berrée Fabienne , Lemiègre Loïc
Published: February 2023

Low molecular weight organogelators provide useful materials which have already found applications in various fields. Recently, phenylboronate alkylglucosides have become new members of this type of organogelators providing water‐sensitive gels. This work is focused on the impact of the position of alkyl and phenyl moieties within this type of structures. Thus, alkylboronate phenylglucoside and alkylboronate alkylglucoside counterparts were synthesized and studied. Organogels obtained in toluene and ethyl myristate were characterized by rheology and electron microscopy. In addition, we also determined the disruption rates of such organogels upon addition of a small amount of water. Alkylboronate alkylglucosides did not induce gelation of the tested solvents but all derivatives bearing a phenyl ring either on the boronate function or on the glucoside unit came out as good organogelators. However, alkylboronates were found to have higher water sensitivities than phenyl counterparts. Thus, this work has enlarged the scope of glucoside‐boronate organogelators and their water sensitivity which can represent useful materials in drug delivery systems for example.
Fully‐Solution‐Processed Enhancement‐Mode Complementary Metal‐Oxide‐Semiconductor Carbon Nanotube Thin Film Transistors Based on BiI3‐Doped Crosslinked Poly(4‐Vinylphenol) Dielectrics for Ultralow‐Power Flexible Electronics
Authors: Li Min , Fang Yuxiao , Shao Shuangshuang , Wang Xin , Chen Zhaofeng , Li Jiaqi , Gu Weibing , Yang Wenming , Xu Wanzhen , Wang Hua , Zhao Jianwen
Published: February 2023

The threshold voltage (Vth) adjustment of complementary metal‐oxide‐semiconductor (CMOS) thin film transistors (TFTs) is one of the research hotspots due to its key role in energy consumption control of CMOS circuits. Here, ultralow‐power flexible CMOS circuits based on well‐matched enhancement‐mode (E‐mode) CMOS single‐walled carbon nanotube (SWCNT) TFTs are successfully achieved through tuning the work function of gate electrodes, electron doping, and printing techniques. E‐mode P‐type CMOS SWCNT TFTs with the full‐solution procedure are first obtained through decreasing the work function of Ag gate electrodes directly caused by the deposition of bismuth iodide (BiI3)‐doped solid‐state electrolyte dielectrics. After synthetic optimization of dielectric compositions and semiconductor printing process, the flexible printed E‐mode SWCNT TFTs show the high Ion/Ioff ratios of ≈106, small subthreshold swing (SS) of 70–85 mV dec−1, low operating voltages of ≈0.5 to −1.5 V, good stability and excellent mechanical flexibility during 10 000 bending cycles. E‐mode N‐type SWCNT TFTs are then selectively achieved via printing the polarity conversion ink (2‐Amino‐2‐methyl‐1‐propanol (AMP)  as electron  doping agent) in P‐ type TFT channels. Last, printed SWCNT CMOS inverters are successfully constructed with full rail‐to‐rail output characteristics and the record unit static power consumption of 6.75 fW µm−1 at VDD of 0.2 V.
Soil hydraulic conductivity in the state of nonequilibrium
Authors: Vogel Hans‐Jörg , Gerke Horst H. , Mietrach Robert , Zahl René , Wöhling Thomas
Published: February 2023

Hydraulic nonequilibrium in soil during water infiltration and drainage is a well‐known phenomenon. During infiltration, water initially invades easily accessible pores before it slowly redistributes towards some state of energetic minimum. In analogy, during drainage, easily drainable pores are emptied more rapidly than those blocked by bottlenecks. The consequence is that the water content is lagging behind the water potential and both state variables do not follow a unique water retention curve as typically assumed when applying Richards equation. Current models that account for nonequilibrium allow for the required decoupling of water content and water potential; however, they do not consider the consequences for the hydraulic conductivity. In this contribution, we present a physically based approach to estimate hydraulic conductivity during nonequilibrium, which depends on both water content and water potential during nonequilibrium conditions. This approach of a dynamic hydraulic conductivity function is demonstrated for an infiltration process into relatively dry soil and for a stepwise drainage and rewetting with decreasing and increasing water fluxes (i.e., multistep flux experiment). The new approach reproduces well‐known phenomena such as pressure overshoot and preferential flow across infiltration fronts using a unified concept for hydraulic conductivity. This was not possible with existing models assuming some fixed unsaturated conductivity function depending on either water content or water potential.
Assessment of the accuracy of counting large ungulate species (red deer Cervus elaphus) with UAV‐mounted thermal infrared cameras during night flights
Authors: Zabel Frank , Findlay Melanie A. , White Patrick J. C.
Published: February 2023

Unmanned aerial vehicles (UAVs) are increasingly used in wildlife surveying, including estimation of population densities. It is essential that we evaluate and test new survey methods to guide optimal sampling strategies. This study aimed to assess the accuracy of using a UAV‐mounted thermal infrared (TIR) camera to count red deer Cervus elaphus populations, and how this was influenced by flight season, height and velocity, in order to help guide future census design. We flew 57 flights across a captive population of red deer in a 13 ha deer park enclosure of semi‐natural habitat, representative of the species' range in northern Germany. Flights and image assessments were performed with no prior knowledge of actual population size. Accuracy was quantified by comparing real population size (known only to deer park staff) and independently estimated population sizes from UAV TIR images. Accuracy was significantly influenced by ecological season (early and late winter, spring and early summer) and height. Across all seasons, lower flights (100 m) performed better than higher ones (120 m), with lower flights in early winter and early summer being on average accurate to within 1% of actual population counts. For the season where we had the largest range of temperatures between flights (late winter) we found that accuracy was highest when temperatures were lowest. Flights were also able to identify all five stags (defined as a male deer ≥ 2 years old) present in early summer, but not in spring. Deer appeared to avoid the landing/take‐off area, but there were no noted behavioural responses to drones flying over animals when at constant height and velocity during surveys. Our results indicate that UAV‐mounted TIR camera have the potential to accurately count populations of large ungulate species, but that flight season, height and potentially temperature need to be taken into account to maximise accuracy. This approach has the potential to be scaled up to more accurately estimate densities of wild populations compared to existing approaches.
How cells sense and integrate information from different sources
Authors: Ullo Maria F. , Case Lindsay B.
Published: February 2023

Cell signaling is a fundamental cellular process that enables cells to sense and respond to information in their surroundings. At the molecular level, signaling is primarily carried out by transmembrane protein receptors that can initiate complex downstream signal transduction cascades to alter cellular behavior. In the human body, different cells can be exposed to a wide variety of environmental conditions, and cells express diverse classes of receptors capable of sensing and integrating different signals. Furthermore, different receptors and signaling pathways can crosstalk with each other to calibrate the cellular response. Crosstalk occurs through multiple mechanisms at different levels of signaling pathways. In this review, we discuss how cells sense and integrate different chemical, mechanical, and spatial signals as well as the mechanisms of crosstalk between pathways. To illustrate these concepts, we use a few well‐studied signaling pathways, including receptor tyrosine kinases and integrin receptors. Finally, we discuss the implications of dysregulated cellular sensing on driving diseases such as cancer.

This article is categorized under:

Cancer > Molecular and Cellular Physiology

Metabolic Diseases > Molecular and Cellular Physiology
Study on Frost Resistance of Steel-PVA Hybrid Fiber Concrete
Authors: Niu Ditao , Gong Siyu , Guo Bingbing , Cao Zhiyuan , Wang Yan
Published: February 2023

Freeze–thaw damage in cold areas is an important reason for the deterioration of durability of concrete structures, and the addition of fiber can effectively improve the frost resistance of concrete. To study the effect of steel fiber and polyvinyl alcohol (PVA) fiber on the frost resistance of concrete, an orthogonal experimental method was applied to analyze the frost resistance of steel-PVA hybrid fiber concrete. The effect of the steel fiber content, PVA fiber content, and steel fiber types were investigated on the mass-loss rate and relative dynamic elastic modulus of fiber concrete, to explore the mechanism of high frost resistance of it. The results show that steel fiber content has a significant effect on the mass-loss rate and relative dynamic elastic modulus of fiber concrete. The influence of PVA fiber content on the relative dynamic elastic modulus is relatively great, and the influence of steel fiber types of the mass-loss rate is the same. The frost resistance of concrete can be improved by adding hybrid fiber in concrete. When 1.0% End-hook steel fibers and 0.3% PVA fibers are added, the concrete specimen has the best frost resistance.
Experimental and Numerical Investigation of Weak-Axis Connected Steel Plate Shear Wall with Non-slotted and Partially Slotted Infill Plates
Authors: Hao Jiping , Wu Xinghuang , Tian Weifeng , Li Shenghui , Wang Rong
Published: February 2023

All Components with H-shaped section are widely used in steel structures, in which the connection of beam section to column flange (i.e. weak-axis connection) is inevitable. In order to study the mechanical properties of weak-axis connected steel plate shear walls, a 1/3 scaled steel plate wall specimen was designed and subjected to a cyclic test to investigate the properties of stiffness, strength, ductility and energy dissipation. On the basis of this, the partially slotted steel plate shear wall was proposed. The FE model of the test specimen was developed and verified with the test results by FE software Abaqus. Subsequently, the FE model of the partially slotted steel plate wall was developed to study mechanical properties by comparing it with the test specimen. The analysis results show that the partially slotted infill plate can fully play the tension field and avoid the beam’s in-span bending, which effectively improves the structural ductility and energy consumption. Although the partially slotted infill plate will weaken the lateral resistance, the partially slotted SPSW still accounts for 75% of that one without slots in lateral bearing capacity. Additionally, the ductility of this partially slotted one is up to 5.79, and its equivalent viscous damping ratio reaches 30%.
Full-Permeability Analysis of Normal Amplitude and Variable Amplitude Fracture of M24 High Strength Bolts
Authors: Xing Rong , Zhang Junjie , Lei Honggang
Published: February 2023

Fatigue problem on high strength bolts have already become more and more important in morden times and it is essential that we do research on bolt fatigue mechanism by the fatigue fracture analysis of the failed bolt because of fatigue. Through detailed analysis of constant amplitude stress and variable amplitude stress on M24 high strength large hexagonal head bolts, it is concluded that there are three common failure mode among all bolts’ fatigue failure. Fatigue failure characteristics and fracture developing status of source region, transient broken zone and extension zone were obtained, and it provides a important basis for the study on fatigue performance and life estimation of high strength bolt connection, and meanwhile it also expands the application range of bolt joint of prefabricated steel structure.
Finite Element Analysis of Anchor Length Detection Method Based on Parallel Seismic Methods
Authors: Hu Yi , Cao Hong Lin , Liu Qiang , Li Xian
Published: February 2023

As an important component of the tunnel support structure, the effective length and compactness of the anchors have a direct impact on the load-bearing capacity and safety. Anchor reinforcement is characterised by rapid construction and concealment. Traditional tension tests are difficult to meet the current requirements for quality control in engineering construction. In recent years, elastic wave anchor non-destructive technology has gradually emerged and achieved certain results, but still cannot solve the identification of anchor lengths in long anchor rods and complex surrounding rock conditions. In this study, the theory of parallel seismic methods is applied to the verification of anchor length by drawing on the technical means of pile foundation detection. The feasibility of the implementation of the method is verified by simulating the anchor-anchor solid-surrounding rock elastic wave conduction system using ABAQUS to analyse the anchor length detection process.
Numerical Simulation of Rockburst Characteristics of Tunnel Surrounding Rock Under Dilatancy Effect
Authors: Yu Jian-qiang , Li Qi , Wang Yong-lu , Tao Shuai
Published: February 2023

Rockburst is one of the most intense reactions in various instability phenomena of underground cavern surrounding rock, which seriously threatens the safety of underground engineering construction personnel and equipment. Based on Mohr–Coulomb strain softening model, the non-associated flow rule is adopted for plastic flow after material yield. By implanting Gu Ming-cheng and Tao Zhen-yu rockburst criterion in the software, the effects of different dilatancy angles on rockburst grade and circumferential stress distribution of surrounding rock of circular tunnel are simulated. The calculation results show that the larger the dilatancy angle is, the more difficult the rock burst pit is to form. The elements of serious rockburst are mainly concentrated in the wall of the tunnel, and the shear bands formed in the high value area of shear strain increment are short. When the dilatancy angle is small, the circumferential stress reaches the maximum at the interface of elastic-plastic zone. With the increase of dilatancy angle, the number of elements entering the plastic state and occurring medium and severe rockburst increases first and then decreases, while the number of elements occurring slight rockburst decreases monotonously. Different dilatancy angles have significant effects on the number of elements occurring rockburst at all levels.
Analysis of the Influence of Foundation Pit Excavation on the Surrounding Surface Settlement and Retaining Structure
Authors: Shou LingChao , Zhao HeQuan , Sun XiaoBo , Pang Jin , Bao Ting , Wang LiFeng
Published: February 2023

This paper analyzes the foundation pit of Gen Shan East Road through tunnels under the river. The results show: When digging to the bottom, the maximum horizontal displacement of the wall is located at 2 ~ 4 m above the bottom of the pit, and the maximum value is 0.57‰ ~ 0.64‰H. The surface subsidence is mainly of groove type. The maximum surface settlement is 0.107%H. The mean value of the maximum surface settlement is about 0.91 times the maximum horizontal displacement of the wall, and the maximum surface settlement is between 0.58 and 1.91 times the maximum horizontal displacement of the wall.
Numerical Simulation with FLAC3D on Excavation Process of Underground Powerhouse of Kaluma Hydropower Station
Authors: Liu An , Li Hua , Lu Fei , Niu Meifeng
Published: February 2023

The dam site of Kaluma Hydropower Station is located on the Nile River in northern Uganda. It is a diversion power station with a total installed capacity of 600 MW. The gneissic fissures and medium dip fissures in the plant area not only reduce the strength of the rock mass, but also easy to form adverse combinations and cuts, which adversely affecting the stability of the cavern. Therefore, surrounding rock deformation and block instability are the key factors affecting the stability of underground caverns. Based on the field investigation data, according to the research of geological prototypes such as rock mass structural plane investigation and quality classification, this paper uses the finite element numerical analysis software FLAC3D to establish and calculate the numerical model, adjusts the boundary conditions of the model through parameter inversion, and then calculates the stress and strain of each part of the rock mass, so as to evaluate the excavation stability of underground powerhouse construction. The actual situation of construction and excavation verifies the accuracy of numerical analysis and calculation.
Measurement of Velocity and Particle Size in Shock Wave Area Generated by Experimental Granular Flow Impacting on a Cylinder Based on Image Processing Methods
Authors: Xu Jing , Wang Jian , Wang Dongpo , Chen Zheng
Published: February 2023

The measurement of flow velocity and particle size remains an important issue in granular -flow dynamics and can provide important basis to better understand the physics in granular material, particularly when it impacts on a structure. In this study, laboratory chute experiments were performed with quartz-glass particle materials to investigate the characteristics of granular shock developed upstream of a cylinder generated by granular flow impacts. A time series of flow images recorded by a camera has been analyzed and processed using the digital image processing methods such as the gray processing, the image binarization, the image corrosion and expansion, and the generative adversarial networks, with a goal of obtaining flow velocity and particle size in the granular shock area. The experimental results reveal that the granular-flow velocity grows with increasing slope angle. The granular shock thickness shows a general increase with the growing number of particles in the shock area, and the number of particles demonstrates an inversely proportional to increasing Froude number, providing a potential method for determining the particle size of dense granular flow. The findings of this study could help to better understand the shock dynamics of granular flow impacting on an obstacle.
Research on Mechanical Properties of Steel Shell Concrete Immersed Tube Shear Connectors
Authors: Xu Guoping , Huang Qingfei , Song Shenyou , Ji Hai , Deng Bin , Song Tian
Published: February 2023

Structural designs of shear connector in immersed tunnel is one of the most significant key technical problems in tunnel designing. According to investigations conducted in Shenzhong Link project, this paper combined numerical simulation methods and experimental verifications and to research effects of shear connector void, stress state, and opening holes on performances of steel–concrete connectors, and also discussed differences of shear slip curves under the influence of factors above, as well as impacts on bearing capacities and stiffnesses of connectors. Through numerical simulations of void and non-void connectors by finite element method, patterns of concrete stress, connector behaviors under tension and compression and shear stresses were analyzed respectively. Additionally, reductions of bearing capacity and stiffness caused by voids and openings which were controlled as variables were discussed. Furthermore, a calculation formula of shear connector bearing capacity is proposed which is in consistent with experimental verifications with considerations of void, stress state and opening. Researches in this paper could provide knowledge for reasonable structural designs of structural connectors in future immersed tunnel engineering construction.
Research on Dam Deformation Monitoring Model Based on BP + SVM Optimal Weighted Combination
Authors: Li Shuangping , Li Yonghua , Zheng Min , Geng Jun , Liu Zuqiang , Shi Bo
Published: February 2023

It is an important means to ensure the safe operation of dam to establish accurate and effective deformation monitoring data analysis and prediction model. In view of the complex conditions in dam safety monitoring, there are many unknown or uncertain factors, and they are difficult to have a single model to apply all problems. The optimal weighted combination method is constructed by combining neural network model and support vector machine model, which is used in the deformation monitoring analysis of concrete dam. The research shows that the prediction results of the optimal weighted combination model are highly consistent with the measured results, and have certain feasibility and practicability in the dam deformation monitoring work.
Equivalent Standard Axle Load Analysis Considering Dynamic Load Based on Vehicle Axle-Tire Vertical Acceleration Field Testing
Authors: Jiang Wei , Wang Wei , Song Zhichao , Jiang Changqing , Zhang Chenglong , Yuan Yijian
Published: February 2023

In order to examine equivalent axles load with dynamic load taken into account, pavement roughness test is carried out with a Vehicle Axle-tire Dynamic Load Tester, where axle-tire vertical acceleration of heavy trucks and light trucks are tested, respectively. Dynamic load is considered as a series of static loads following a normal distribution, and equivalent axles load is calculated according the Asphalt Pavement Design Specification. The results show that equivalent axles load time increase accordingly based on highway class. when tensile strain at bottom of surface is taken as design index, on high class highway equivalent standard load increases 8.3–14.9% for heavy truck, 3.6–5.4% for light truck; on low class highway, it increases 6.8–17.3% for heavy truck, 3.2–12.5% for light truck; when tensile stress at the bottom of semi-rigid base is taken as checking index. On a high class highway, it increases 34.2–64.9% for a heavy truck, 14.2–21.8% for a light truck; on a low class highway, it increases 27.5–77.1% for a heavy truck, 12.6–53.2% for a light truck. These research findings provide in-depth understanding regarding vehicle axle load conversion in dynamic load environment.
Experimental Study on Mechanical Properties of the Damaged Hoop Head Mortise-Tenon Joint
Authors: Peng Chengwei , Lv Wenlong
Published: February 2023

Damage is a common condition in ancient timber structures, whose influence on the mechanical properties of structures cannot be ignored. To study the mechanical properties of damaged hoop head mortise-tenon joint, four specimens with shrinkage gauge, including one intact joint specimen and three artificial simulated damaged joint specimens, are designed, and fabricated in this paper by regarding the global damage degree and column axial force as the variation of parameters. The failure mode, hysteresis curve, skeleton curve, ductility, and energy dissipation capacity of the specimens are studied by low-cyclic reversed loading tests. The results show that the failure pattern is randomly manifested as parallel-to-grain tensile cracking failure or vertical splitting failure of the beam tenon. When the global damage degree increases, the two types of damage are more likely to appear simultaneously. The global damage degree has a significant influence on the ultimate bending moment and energy dissipation capacity of hoop head mortise-tenon joints, and 2.4% of the global damage degree can lead to a significant decrease in both. The column axial force can affect the ultimate bending moment, ductility, and energy dissipation capacity of hoop head mortise-tenon joints. When the column axial force increases, the ultimate bending moment and energy dissipation capacity will increase, while the ductility will decrease.
Research on Deformation Characteristics of SCP Foundation for HKZM Bridge
Authors: Li Bin , Zhang Jiaying , Zhang Xuelei , Tian Zhongke
Published: February 2023

To further determine the bearing capacity of sand compaction pile (SCP) composite foundation in the West artificial island of Hong Kong-Zhuhai-Macao (HKZM) Bridge, a large-scale in-situ load test system was designed to study the mechanical and deformation characteristic of SCP foundation. The test adopts the anchor pile method, the results show that the stress sharing ratio of the underwater SCP foundation under the same replacement rate is closely related to the load and time. With the increase of load level, the curve of stress sharing ratio decreases first and then increases. Under the same load level, the ratio decreases gradually with time and finally approaches a certain value. Based on the analysis of site monitoring data, the settlement law of SCP is clear, and the error of the empirical formula is found. The stress reduction ratio and empirical coefficient are proposed to correct the original formula. The research results in this paper can be used to guide the design and construction of SCP foundation of cross-sea project.
Research on Vibration Design of Large Compressor Foundation
Authors: Qiao Xiaoshuai , Sun Chao , Hu Yanzheng , Jiang Congbin
Published: February 2023

The safe operation of a compressor machine heavily relies on the proper design of its foundation. The frame-type supporting foundation is usually adopted in engineering. This paper studies the vibration design of the compressor’s foundation. Two types of finite element model for the foundation are considered, which are beam-slab element model and solid element model. By the comparative analysis of vibration mode shape and time-history dynamic calculation, it is concluded that the commonly used beam-slab element model could be unsafe for a design purpose. In contrast, the solid element model is more reliable. Then, the solid element model was used to study the influence of structural arrangement parameters on vibration response, including roof thickness, column’s section size, eccentric unit arrangement and plate cantilever length. It is concluded that the thickness of the top plate has the most significant influence on the vibration response compared to other factors.
Theoretical Study of the Reinforcement of Pre-stressed Concrete Cylinder Pipes with External Pre-stressed Strands
Authors: Zhao Lijun , Dou Tiesheng
Published: February 2023

Reinforcement of the pre-stressed concrete cylinder pipes with external pre-stressed strands is an effective way to enhance a prestressed concrete cylinder pipe’s ability to bear the design hydraulic pressure. A theoretical derivation is studied, and this formula derivation could be used to determine the cross-sectional area per unit length. This derivation determine the cross-sectional area and target tensile strength of steel strands in order to meet the requirements of ultimate limit states, serviceability limit states, and quasi-permanent limit states. The theoretical results agree well with the experimental results. This paper could provide technical supports for the application of the external reinforcement of PCCPs with strands.
Experimental Study on Inclination Test of Fiber Bragg Grating
Authors: Tan Kang , Dong Ping , Gou Wanchun , Guo Qi , Li Yi
Published: February 2023

Deep displacement monitoring is an important means to monitor the deformation of slope, landslide and deep foundation pit. Traditional deep displacement monitoring uses manual inclinometer, which is time-consuming and laborious, and has large manual operation error, so it is impossible to realize automatic monitoring. It is urgent to adopt new technical means to make up for these shortcomings. Based on fiber Bragg grating sensing technology and beam bending theory, this paper establishes the calculation formula of fiber Bragg grating deep inclinometer, which can calculate the deep displacement curve of inclinometer through the change of fiber Bragg grating center wavelength; The strain sensitivity coefficient of fiber Bragg grating is calibrated by indoor calibration test. The experimental results show that the center wavelength of fiber Bragg grating has a high correlation with strain, and the relationship is linear. The strain and displacement of inclinometer tube are monitored and compared by indoor model test. The test results show that the displacement error calculated by fiber Bragg grating is 2% ~ 12%, which can meet the needs of deep displacement monitoring. The relevant conclusions provide a certain reference for the research of fiber Bragg grating deep displacement monitoring.
Transverse Vibration Characteristics of Clamped-Elastic Pinned Beam Under Compressive Axial Loads
Authors: Zhang Jianxun , Zhang Pengchong , Song Huicun , Zhu Lei
Published: February 2023

Based on the Bernoulli–Euler theory, the vibration characteristics of a clamped-elastic pinned beam under the elastic constraint and the compressive axial loads are derived and verified by finite element method. The results of examples show that the natural frequency of the beam decreases with loads increase and the frequency increases with the increase of the elastic constraint stiffness. When the constraint stiffness increases from 104 to 108 N/m, the first-order natural frequency becomes 4.24 times, the second-order natural frequency becomes 2.19 times, and the third-order natural frequency becomes 1.57 times; when the constraint is weak, the loads change is mainly reflected in the first mode shape. When the constraint stiffness is 104 N/m, the first-order natural frequency decreases by 20%, the second-order modal natural frequency changes by 3%, and the third-order natural frequency changes by less than 1%. The range of the elastic constraints with significant changes in the natural frequencies of the higher-order modes is larger. When the first-order frequency is taken to 100EI/l3, the change tends to be flat, the second-order frequency is about five times that of the first-order, and the range of the third-order frequency is 15 times or more.
Rail Surface Defect Detection Method Based on Deep Learning Method with 3D Range Image
Authors: Ming Geng , Zhou Bo , Luo Xiaohua , Ling Ren , Zhou Mingxiang
Published: February 2023

In the methods of using images for detecting surface defects of rails, the interaction such as light, stains, and water stains will cause false alarms. This paper proposals a method to detect surface defects of rails using 3D range line scan cameras combined with deep learning. By using the 3D range camera to acquire the information and 2D image information, and optimizing The original internet neural network structure, combined with the channel attention mechanism, a twin unet & 3D+ neural network model is proposed. First, the required database was established by using the 3D range camera, and then the comparison experts provided that the neural network proposed in this paper can effectually eliminate false alarms caused by light, Stains and water stains compared with other neural networks, and effectually promoted the rail surface. The correct rate of default detection.
Theoretical Study on Natural Vibration Frequency of Externally Prestressed Simply Supported Steel Beams
Authors: Wang Zhengyu , Li Hongming , Chen Huibin
Published: February 2023

Prestress is an important index of the mechanical performance of prestressed structures, which will have a certain impact on the natural vibration frequency of the structure. In this paper, based on the action mechanism of the prestressing system, the externally prestressed simply supported steel beams are classified, and the energy method is used to establish the dynamic equations of the prestressed steel beams with three forms of cable distribution, with a view to exploring the relationship between the magnitude of prestressing force, cable distribution form, and cable section size and the natural vibration frequency of externally prestressed simply-supported steel beams. Through a numerical example, the theoretical calculation results are compared with the finite element simulation results to verify the theoretical calculation formula derived in this paper and reveal the action law of the prestressed system on the natural vibration frequency of the simply supported steel beam.
Finite Element Analysis of Punching Shear of Reinforced Concrete Mushroom Slab-Column Connections Using ABAQUS
Authors: Jia Yueqiao , Chiang Jeffrey Choong Luin
Published: February 2023

Capital is one of the common measures to strengthen the slab-column connections. It can make the joint's load capacity increase. However, when the connection is subjected to the unbalanced bending moment, the reduction effect of the capital on the bending moment is to be studied. Nonlinear finite element analysis is performed on reinforced concrete slabs with column capital for various moment-to-shear (M/V) ratios. The effect of capital radius on the punching shear resistance of slab-column connections is investigated. The 3D finite element modeling is performed using the concrete damage plasticity model and concrete constitutive equations. The concrete damage plasticity model parameters are calibrated by the experiment results of specimens. Increasing the radius of capital can improve the bearing capacity of nodes and reduce the moment transfer effect obviously.
Identifying Large Charge operators
Authors: Badel Gil , Monin Alexander , Rattazzi Riccardo
Published: February 2023

Abstract

The Large Charge sector of Conformal Field Theory (CFT) can generically be described through a semiclassical expansion around a superfluid background. In this work, focussing on U(1) invariant Wilson-Fisher fixed points, we study the spectrum of spinning large charge operators. For sufficiently low spin these correspond to the phonon excitations of the superfluid state. We discuss the organization of these states into conformal multiplets and the form of the corresponding composite operators in the free field theory limit. The latter entails a mapping, built order-by-order in the inverse charge n−1, between the Fock space of vacuum fluctuations and the Fock space of fluctuations around the superfluid state. We discuss the limitations of the semiclassical method, and find that the phonon description breaks down for spins of order n1/2 while the computation of observables is valid up to spins of order n. Finally, we apply the semiclassical method to compute some conformal 3-point and 4-point functions, and analyze the conformal block decomposition of the latter with our knowledge of the operator spectrum.
A general cost model to assess the implementation of collaborative robots in assembly processes
Authors: Barravecchia Federico , Mastrogiacomo Luca , Franceschini Fiorenzo
Published: February 2023

In assembly processes, collaborative robots (cobots) can provide valuable support to improve production performance (assembly time, product quality, worker wellbeing). However, there is a lack of models capable of evaluating cobot deployment and driving decision-makers to choose the most cost-effective assembly configuration. This paper tries to address this gap by proposing a novel cost model to evaluate and predict assembly costs. The model allows a practical and straightforward comparison of different potential assembly configurations in order to guide the selection towards the most effective one. The proposed cost model considers several cost dimensions, including manufacturing, setup, prospective, retrospective, product quality and wellbeing costs. The cost estimation also considers learning effects on assembly time and quality, particularly relevant in low-volume and mass customised productions. Three real manufacturing case studies accompany the description of the model.
Insights in opiates toxicity: impairment of human vascular mesenchymal stromal cells
Authors: Mazzotti Maria Carla , Teti Gabriella , Giorgetti Arianna , Carano Francesco , Pelletti Guido , Pascali Jennifer Paola , Falconi Mirella , Pelotti Susi , Fais Paolo
Published: February 2023

The most common pulmonary findings in opiate-related fatalities are congestion and oedema, as well as acute and/or chronic alveolar haemorrhage, the cause of which is thought to be a damage to the capillary endothelium related to ischemia. Human vascular mesenchymal stromal cells (vMSCs) play a fundamental role in tissue regeneration and repair after endothelial cell injury, and they express opioid receptors. The aim of this study was to assess the effect of in vitro morphine exposure on the physiological activity and maintenance of human vMSCs. vMSCs were obtained from abdominal aorta fragments collected during surgery repair and were exposed to incremental doses (0.1 mM, 0.4 mM, 0.8 mM and 1 mM) of morphine sulphate for 7 days. The effect was investigated through cell viability assessment, proliferation assay, reactive oxygen species (ROS) detection assay, senescence-associated β-galactosidase assay, senescent-related markers (p21WAF1/CIP1 and p16INK4) and the apoptosis-related marker caspase 3. Moreover, an ultrastructural analysis by transmission electron microscopy and in vitro vascular differentiation were evaluated. Results showed a decrease of the cellular metabolic activity, a pro-oxidant and pro-senescence effect, an increase in intracellular ROS and the activation of the apoptosis signalling, as well as ultrastructural modifications and impairment of vascular differentiation after morphine treatment of vMSC. Although confirmation studies are required on real fatal opiate intoxications, the approach based on morphological and immunofluorescence methodologies may have a high potential also as a useful tool or as a complementary method in forensic pathology. The application of these techniques in the future may lead to the identification of new markers and morphological parameters useful as complementary investigations for drug-related deaths.
Evidence of natural selection and dominance of SARS-CoV-2 variant Lambda (C.37) over variants of concern in Cusco, Peru
Authors: Quispe-Ricalde Maria Antonieta , Castelán-Sánchez Hugo G. , Meza-Rodríguez Pablo M. , Dávila-Ramos Sonia , Sierra José Luis , Batista-Garcia Ramón , Concha-Velasco Fátima , Lucana Sonia Flores , De Santa Cruz José , Zea Víctor , Galarza Marco , Caceres-Rey Omar , Tsukayama Pablo , Foronda Pilar , Soto-Chambi Brandon Jason , Abreu Nestor
Published: February 2023

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineage C.37 (Lambda) has spread rapidly in Peru and other Latin American countries. However, most studies in Peru have focused on Lima, the capital city, without knowing the dynamics of the spread of the variant in other departments. Cusco, Peru, is one of the most popular departments in the country for tourists, so the introduction of new variants of SARS-CoV-2 might occur despite closure of the borders. Therefore, in this work, we analyzed the variants circulating in Cusco. The aim of this work was to better understand the distribution of SARS-CoV-2 lineages circulating in Cusco and to characterize the genomes of these strains. To this end, 46 SARS-CoV-2 genomes from vaccinated and unvaccinated patients were sequenced in the first half of 2021. The genomes were analyzed using phylogenetic and natural selection methods. Phylogenetic trees from Cusco showed dominance of the Lambda lineage over the variants of concern (VOCs), and there was no clustering of variants by district. Natural selection analysis revealed mutations, mainly in the spike protein, at positions 75, 246, 247, 707, 769, and 1020. In addition, we found that unvaccinated patients accumulated more new mutations than did vaccinated patients, and these included the F101Y mutation in ORF7a, E419A in NSP3, a deletion in S (21,618-22,501), and a deletion in ORF3a (25,437-26,122).
The relationship between basic psychological need satisfaction and intrinsic motivation: The role of individual differences and special educational needs
Authors: Loopers Judith , Kupers Elisa , de Boer Anke , Minnaert Alexander
Published: February 2023

A within-person perspective with several measurement points per individual allows to analyse relations between variables within individuals. Such an approach is still scarce in research from a self-determination theory perspective. Therefore, this study measured basic psychological need satisfaction and intrinsic motivation in real-time and at several lessons with the experience sampling method. In this way, the relationship between need satisfaction and intrinsic motivation was investigated from both a group level and within-person perspective. The sample consisted of 146 students in pre-vocational secondary education, who completed 4128 diary questionnaires. At the group level, positive relationships between satisfaction of the needs and motivation were found. However, individual differences in the strength and direction of these relationships exist. This marks the importance of taking a within-person perspective, and studying both concepts at several lessons and individually. Students’ special educational needs play a role in the strength of the relationship: compared to typically developing students, satisfaction of autonomy is less important, while satisfaction of competence and relatedness with the teacher are more important for the intrinsic motivation of students with special educational needs. However, students’ special educational needs do not explain all differences between individual students. Future research may investigate other student characteristics to explore where individual differences in the importance of the basic psychological needs come from.
Unraveling the contextuality of adolescents’ interest pursuits in daily life: four latent configurations
Authors: Beek Gregorius J. , Bronkhorst Larike H. , Akkerman Sanne F.
Published: February 2023

While interest pursuits are widely recognized as being inherently contextual, what this contextuality entails for different interests has not been explored systematically. In this study, 410 adolescents reported on the temporal, epistemic, material, geographical, social, institutional, and cultural dimensions of 820 interest pursuits. Latent class analyses identified four interest pursuit configurations, revealing quantitative (overall high/low structure) and qualitative (expertise- and social-oriented) differences. We observed similar interests being pursued in the same configuration, but also identified individual differences, reflecting the social–historical meaning and object characteristics of interests, as well as adolescents’ preferences and structural opportunities. The findings show that interest entails more than a preference for an object, but also a preference for a wider configuration, which should be considered when designing (educational) contexts to stimulate adolescents’ interest.
Predicting the performance of MSMEs: a hybrid DEA-machine learning approach
Authors: Boubaker Sabri , Le Tu D. Q. , Ngo Thanh , Manita Riadh
Published: February 2023

Micro, small and medium enterprises (MSMEs) dominate the business landscape and create more than half of employment worldwide. How we can apply big data analytical tools such as machine learning to examine the performance of MSMEs has become an important question to provide quicker results and recommend better and more reliable solutions that improve performance. This paper proposes a novel method for estimating a common set of weights (CSW) based on regression analysis for data envelopment analysis (DEA) as an important analytical and operational research technique, which (i) allows for measurement evaluations and ranking comparisons of the MSMEs, and (ii) helps overcome the time-consuming non-convexity issues of other CSW DEA methodologies. Our hybrid approach used several econometric and machine learning techniques (such as Tobit, least absolute shrinkage and selection operator, and Random Forest regression) to empirically explain and predict the performance of more than 5400 Vietnamese MSMEs (2010‒2016), and showed that the machine learning techniques are more efficient and accurate than the econometric ones. Our study, therefore, sheds new light on the two-stage DEA literature, especially in terms of predicting performance in the era of big data to strengthen the role of analytics in business and management.
Effects of preoperative magnetic resonance image on survival rates and surgical planning in breast cancer conservative surgery: randomized controlled trial (BREAST-MRI trial)
Authors: Mota Bruna Salani , Reis Yedda Nunes , de Barros Nestor , Cardoso Natália Pereira , Mota Rosa Maria Salani , Shimizu Carlos , de Mello Tucunduva Tatiana Cardoso , de Siqueira Ferreira Vera Christina Camargo , Goncalves Rodrigo , Doria Maíra Teixeira , Ricci Marcos Desidério , Trinconi Angela Francisca , Camargo Cristina Pires , Riera Rachel , Baracat Edmund Chada , Soares Jr José Maria , Filassi José Roberto
Published: February 2023

Background

Breast magnetic resonance imaging (MRI) has high sensitivity in detecting invasive neoplasms. Controversy remains about its impact on the preoperative staging of breast cancer surgery. This study evaluated survival and surgical outcomes of preoperative MRI in conservative breast cancer surgery.

Methods

A phase III, randomized, open-label, single-center trial including female breast cancer participants, stage 0–III disease, and eligible for breast-conserving surgery. We compared the role of including MRI in preoperative evaluation versus radiologic exam routine with mammography and ultrasound in breast cancer conservative candidates. The primary outcome was local relapse-free survival (LRFS), and secondary outcomes were overall survival (OS), mastectomy rate, and reoperation rate.

Results

524 were randomized to preoperative MRI group (n = 257) or control group (n = 267). The survival analysis showed a 5.9-years LRFS of 99.2% in MRI group versus 98.9% in control group (HR = 0.72; 95% CI 0.12—4.28; p = 0.7) and an OS of 95.3% in the MRI group versus 96.3% in the control group (HR = 1.37 95% CI 0.59–3.19; p = 0.8). Surgical management changed in 21 ipsilateral breasts in the MRI group; 21 (8.3%) had mastectomies versus one in the control group. No difference was found in reoperation rates, 22 (8.7%) in the MRI group versus 23 (8.7%) in the control group (RR = 1.002; 95% CI 0.57–1.75; p = 0.85).

Conclusion

Preoperative MRI increased the mastectomy rates by 8%. The use of preoperative MRI did not influence local relapse-free survival, overall survival, or reoperation rates.