Experimental Investigation of Progressive Collapse of Steel Frames

This paper reports two new tests conducted to augment available data highlighting the structural performance of multistory steel frames under progressive collapse. The investigated steel frames had different geometries, different boundary conditions, different collapse mechanisms, different damping ratios and different connections. Overall, the paper addresses how multistory frames would behave when subjected to local damage or loss of a main structural carrying element. The obtained results can form a data base for nonlinear finite element models. The deformations of the investigated steel frames and failure modes under progressive collapse were predicted from the finite element analysis, with detailed discussions presented.

Recent Experimental Progress in the HT-7 Tokamak

Recent experimental campaign in the HT-7 toka-mak was scheduled to be ran from November 2002 toMarch 31, 2003, during which various issues were in-vestigated on getting high electron temperature, longpulse discharges and high performance plasma underquasi-steady-state condition. New systems includ-ing LHCD launcher, cryogenic compressor, real-timepoloidal control, water-cooled toroidal belt limiter,ferretic liner and several diagnostics were installedand operated to satisfy long-pulse operation require-ments. The maximum total injected power was over1 MW and the longest discharge duration was nearto 64 s.

5-13 Thermohydraulics Experimental Research Progress of Spallation Target

In order to verify the simulation results of the liquid metal target and the granular flow target, the spallationtarget laboratory have established several experimental benches and carried out some related experiments on thesebenches.1. Liquid Target ResearchA water loop has been established in 2012 for investigating the flow behaviors of water in windowless target andhas been rebuilt in 2014 for experiments of window target. The experiments are conducted in an approximately 1:1sized window target model shown in Fig. 1. The flow pattern inside the spallation area is visualized by means ofthe particle image velocimetry (PIV). The flow range of the present experiment is between 8.4 and 20 m3/h, andseveral typical flow patterns are observed under the conditions of different inlets and outlets.

PROGRESSES MADE IN EXPERIMENTAL STUDIES OF SHALLOW-WATER ACOUSTICS

Acomprehensive experiment on shallow water acoustics with the inseparable combination of the acoustical and oceanographic means, which is uncommon internationally, was conducted successfully in the Far Yellow Sea by a group of Chinese and U.S. scientists from August 21 to September 1,1996. The basic task of ocean acoustic research is to study the interaction between sound wave and ocean media, which includes exploring the laws of influence due to spatial and temporal variability of the ocean environment, such as ocean surface waves,inhomogeneity of sea water and sea bottom struc-

PROGRESS OF MARINE METEOROLOGICAL OBSERVATION EXPERIMENT AT MAOMING OF SOUTH CHINA

The coastal area of southern China is frequently affected by marine meteorological disasters,and is also one of the key areas that influence the short-term climate change of China.Due to a lack of observational facilities and techniques,little has been done in this area in terms of operational weather monitoring and scientific research on atmospheric and marine environment.With the support of China Meteorological Administration (CMA) and Guangdong Meteorological Bureau (GMB),the Marine Meteorological Science Experiment Base (MMSEB) at Bohe,Maoming has been jointly established by Guangzhou Institute of Tropical and Marine Meteorology (GITMM) and Maoming Meteorological Bureau (MMB) of Guangdong Province after three years of hard work.It has become an integrated coastal observation base that is equipped with a complete set of sophisticated instruments.Equipment maintenance and data quality control procedures have been implemented to ensure the long-term,steady operation of the instruments and the availability of high quality data.Preliminary observations show that the data obtained by the MMSEB reveal many interesting features in the boundary layer structure and air-sea interaction in such disastrous weather as typhoons and sea fog.The MMSEB is expected to play an important role in the scientific research of disastrous weather related to marine meteorology.

Experimental study on seismic response and progressive failure characteristics of bedding rock slopes

Bedding rock slopes are common geological features in nature that are prone to failure under strong earthquakes. Their failures induce catastrophic landslides and form barrier lakes, posing severe threats to people’s lives and property. Based on the similarity criteria, a bedding rock slope model with a length of3 m, a width of 0.8 m, and a height of 1.6 m was constructed to facilitate large-scale shaking table tests.The results showed that with the increase of vibration time, the natural frequency of the model slope decreased, but the damping ratio increased. Damage to the rock mass structure altered the dynamic characteristics of the slope;therefore, amplification of the acceleration was found to be nonlinear and uneven. Furthermore, the acceleration was amplified nonlinearly with the increase of slope elevation along the slope surface and the vertical section, and the maximum acceleration amplification factor(AAF) occurred at the slope crest. Before visible deformation, the AAF increased with increasing shaking intensity;however, it decreased with increasing shaking intensity after obvious deformation. The slope was likely to slide along the bedding planes at a shallow depth below the slope surface. The upper part of the slope mainly experienced a tensile-shear effect, whereas the lower part suffered a compressive-shear force. The progressive failure process of the model slope can be divided into four stages, and the dislocated rock mass can be summarized into three zones. The testing data provide a good explanation of the dynamic behavior of the rock slope when subjected to an earthquake and may serve as a helpful reference in implementing antiseismic measures for earthquake-induced landslides.

Disturbed bone remodelling activity varies in different stages of experimental, gradually progressive apical periodontitis in rats

Bone remodelling keeps going through the lifespan of human by bone formation and bone resorption.In the craniofacial region,mandibles act as the main force for biting and chewing,and also become susceptible to a common bone-loss disease,namely,apical periodontitis,once infected dental pulp is not treated timely,during which bone resorption occurs from the apical foramen to the apical bone area.Although conventional root canal treatment(RCT)can remove the most of the infection,chronical apical periodontitis due to incomplete removal of dental pulp and subsequent microleakage will become refractory and more challenging,and this process has scarcely been specifically studied as a bone remodelling issue in rat models.Therefore,to study chronical and refractory apical periodontitis owing to incomplete cleaning of infected dental pulp and microleackage in vivo,we establish a modified rat model of gradually progressive apical periodontitis by sealing residual necrotic dental pulp and introducing limited saliva,which simulates gradually progressive apical periodontitis,as observed in the clinical treatment of chronical and refractory apical periodontitis.We show that bone-loss is inevitable and progressive in this case of apical periodontitis,which confirms again that complete and sound root canal treatment is crucial to halt the progression of chronical and refractory apical periodontitis and promote bone formation.Interestingly,bone remodelling was enhanced at the initial stage of apical periodontitis in this model while reduced with a high osteoblast number afterwards,as shown by the time course study of the modified model.Suggesting that the pathological apical microenvironment reserve its hard tissue formation ability to some degree but in a disturbed manner.Hopefully,our findings can provide insights for future bone regenerative treatment for apical periodontitisassociated bone loss.

Recent Progress in JAXA Project of Boiling Two-Phase Flow Experiment onboard ISS

The amount of waste heat in a space facility became larger, because of increase in the space platform size and its power consumption. It requires development of high-performance space thermal management systems handling a large amount of waste. Boiling two-phase flow could become powerful means for this system because a boiling and condensation system is one of the most efficient modes of heat transfer due to phase change （liquid-vapor）. However, gravity effects on boiling two-phase flow phenomena and the corresponding heat transfer characteristics are not clear. Therefore, we prepare the experiments of boiling two-phase flow utilizing a long-term microgravity environment onboard a Japanese Experimental Module ＂KIBO＂ in the International Space Station （ISS） as one of the JAXA official projects. In this paper, recent progress of the preparation for the project is reported.

Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation

Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.

Application and Practice of Knowledge Graph in Experimental Teaching in Colleges and Universities

With the reform of experimental teaching in colleges and universities,the teaching mode of"experimental students as the main body,experimental teachers as the guide"needs to constantly explore new experimental teaching methods.In this paper,knowledge graph is integrated into the experiment of mechanical principle to guide undergraduates to use knowledge graph to analyze and summarize independently in experimental teaching activities,aiming at cultivating undergraduates interest in learning and innovative thinking,so as to improve the quality of experimental teaching.This study has a certain reference significance for experimental teaching in colleges and universities.

Role of exosomal circular RNAs as microRNA sponges and potential targeting for suppressing hepatocellular carcinoma growth and progression

In this editorial,we comment on the article by Lyu et al published in the recent issue of the World Journal of Gastroenterology(2023;2219-2840).Hepatocellular carcinoma(HCC)is a frequently encountered and highly aggressive primary liver cancer,which remains the third-commonest cause of cancer-related death despite the current therapeutic modalities.There is urgency in developing novel thera-peutic approaches,such as by manipulating extracellular vesicles,which con-stitute a highly heterogeneous nanoparticle population that contains various cargoes.These cargoes have a pivotal role in cell-to-cell communication and can modify the functional level of the recipient cells via their uptake by other recipient cells.Exosomal non-coding RNAs have particular evolving significance in HCC,such as circular RNAs,which have been found differentially expressed in normal hepatic and HCC tissues.The aberrations in their expression levels have a key role in the HCC development and progression and the overall prognosis.In this editorial,we will shed light on the emerging role of exosomal circular RNAs in HCC development and progression,focusing on the oncogenic or potentially tumor suppressive effect of mesenchymal stem cells-derived exosomal non-coding RNAs.

Progress in the generation of spinal cord organoids over the past decade and future perspectives

Spinal cord organoids are three-dimensional tissues derived from stem cells that recapitulate the primary morphological and functional characteristics of the spinal cord in vivo.As emerging bioengineering methods have led to the optimization of cell culture protocols,spinal cord organoids technology has made remarkable advancements in the past decade.Our literature search found that current spinal cord organoids do not only dynamically simulate neural tube formation but also exhibit diverse cytoarchitecture along the dorsal-ventral and rostral-caudal axes.Moreover,fused organoids that integrate motor neurons and other regionally specific organoids exhibit intricate neural circuits that allows for functional assessment.These qualities make spinal cord organoids valuable tools for disease modeling,drug screening,and tissue regeneration.By utilizing this emergent technology,researchers have made significant progress in investigating the pathogenesis and potential therapeutic targets of spinal cord diseases.However,at present,spinal cord organoid technology remains in its infancy and has not been widely applied in translational medicine.Establishment of the next generation of spinal cord organoids will depend on good manufacturing practice standards and needs to focus on diverse cell phenotypes and electrophysiological functionality evaluation.

Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies

Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease management.This review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and management.It delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive immunity.Viral factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are examined.Notably,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease progression.HBV reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is detailed.Management strategies,including anti-viral and immunomodulatory approaches,are critically analyzed.The role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent reactivation.In conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV reactivation.With a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge base.The more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient outcomes.The dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory approaches.The role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

Computer Management of Quantitative Analysis Chemistry Experiment

The application of computer in the quantitative analysis chemistry experiment is a chemistry experiment teaching applications software, developed by Visual Basic （6.0）, based on the content of quantitative analysis chemistry experiment of chemistry major in higher institute. This software has the function of the automatic processing the experimental data, the automatic generation of test report copies, and the automatic evaluation of students＇ experimental results, which solve the reliability, objectivity and accuracy problems of the students＇ experiment data processing and evaluation, and avoid interference with human factors. The software has the characteristic of the easy installation, the easy operation, the strong practicability, pertinence, the systematicness and the running stability, so it provides a platform in the quantitative analysis chemistry experiment for the students＇ assessment system of automatic processing, and it has a high popularization value. The project＇s technical route design is reasonable, the research method is correct, and the experimental data processing results are reliable, which has reached the leading domestic level in the quantitative analysis chemistry experiment teaching field of computer data processing. And this project has been through the achievements appraisal of Gansu Provincial Sci. ＆ Tech. Department.

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water environments.To investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are conducted.For the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary effects.As for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with water.It has been observed that the cross-section of the middle part collapses when it reaches the maximum pressure.The collapse pressure obtained from the numerical simulations agrees well with that in the experiment.Meanwhile,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also discussed.It has a relatively greater difference because of the ignorance of the progressive failure of composites.For the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

Predicting the probability distribution of Martian rocks mechanical property based on microscale rock mechanical experiments and accurate grain-based modeling

The exploration of Mars would heavily rely on Martian rocks mechanics and engineering technology.As the mechanical property of Martian rocks is uncertain,it is of utmost importance to predict the probability distribution of Martian rocks mechanical property for the success of Mars exploration.In this paper,a fast and accurate probability distribution method for predicting the macroscale elastic modulus of Martian rocks was proposed by integrating the microscale rock mechanical experiments(micro-RME),accurate grain-based modeling(AGBM)and upscaling methods based on reliability principles.Firstly,the microstructure of NWA12564 Martian sample and elastic modulus of each mineral were obtained by micro-RME with TESCAN integrated mineral analyzer(TIMA)and nanoindentation.The best probability distribution function of the minerals was determined by Kolmogorov-Smirnov(K-S)test.Secondly,based on best distribution function of each mineral,the Monte Carlo simulations(MCS)and upscaling methods were implemented to obtain the probability distribution of upscaled elastic modulus.Thirdly,the correlation between the upscaled elastic modulus and macroscale elastic modulus obtained by AGBM was established.The accurate probability distribution of the macroscale elastic modulus was obtained by this correlation relationship.The proposed method can predict the probability distribution of Martian rocks mechanical property with any size and shape samples.

Imbalance of Circulating Follicular Regulatory and Follicular Helper T Cell Subpopulations Is Associated with Disease Progression and Serum CYFRA 21-1 Levels in Patients with Non-small Cell Lung Cancer

Objective This study aimed to investigate the changes of follicular helper T(TFH)and follicular regulatory T(TFR)cell subpopulations in patients with non-small cell lung cancer(NSCLC)and their significance.Methods Peripheral blood was collected from 58 NSCLC patients at different stages and 38 healthy controls.Flow cytometry was used to detect TFH cell subpopulation based on programmed death 1(PD-1)and inducible co-stimulator(ICOS),and TFR cell subpopulation based on cluster determinant 45RA(CD45RA)and forkhead box protein P3(FoxP3).The levels of interleukin-10(IL-10),interleukin-17a(IL-17a),interleukin-21(IL-21),and transforming growth factor-β(TGF-β)in the plasma were measured,and changes in circulating B cell subsets and plasma IgG levels were also analyzed.The correlation between serum cytokeratin fragment antigen 21-1(CYFRA 21-1)levels and TFH,TFR,or B cell subpopulations was further explored.Results The TFR/TFH ratio increased significantly in NSCLC patients.The CD45RA^(+)FoxP3^(int) TFR subsets were increased,with their proportions increasing in stages Ⅱ to Ⅲ and decreasing in stage IV.PD-1^(+)ICOS+TFH cells showed a downward trend with increasing stages.Plasma IL-21 and TGF-β concentrations were increased in NSCLC patients compared with healthy controls.Plasmablasts,plasma IgG levels,and CD45RA^(+)FoxP3^(int) TFR cells showed similar trends.TFH numbers and plasmablasts were positively correlated with CYFRA 21-1 in stages Ⅰ-Ⅲ and negatively correlated with CYFRA 21-1 in stage IV.Conclusion Circulating TFH and TFR cell subpopulations and plasmablasts dynamically change in different stages of NSCLC,which is associated with serum CYFRA 21-1 levels and reflects disease progression.

Network pharmacology study and in vitro experimental validation of Xiaojianzhong decoction against gastric cancer

BACKGROUND Cancer is one of the most serious threats to human health worldwide.Conventional treatments such as surgery and chemotherapy are associated with some drawbacks.In recent years,traditional Chinese medicine treatment has been increasingly advocated by patients and attracted attention from clinicians,and has become an indispensable part of the comprehensive treatment for gastric cancer.AIM To investigate the mechanism of Xiaojianzhong decoction(XJZ)in the treatment of gastric cancer(GC)by utilizing network pharmacology and experimental validation,so as to provide a theoretical basis for later experimental research.METHODS We analyzed the mechanism and targets of XJZ in the treatment of GC through network pharmacology and bioinformatics.Subsequently,we verified the impact of XJZ treatment on the proliferative ability of GC cells through CCK-8,apoptosis,cell cycle,and clone formation assays.Additionally,we performed Western blot analysis and real-time quantitative PCR to assess the protein and mRNA expression of the core proteins.RESULTS XJZ mainly regulates IL6,PTGS2,CCL2,MMP9,MMP2,HMOX1,and other target genes and pathways in cancer to treat GC.The inhibition of cell viability,the increase of apoptosis,the blockage of the cell cycle at the G0/G1 phase,and the inhibition of the ability of cell clone formation were observed in AGS and HGC-27 cells after XJZ treatment.In addition,XJZ induced a decrease in the mRNA expression of IL6,PTGS2,MMP9,MMP2,and CCL2,and an increase in the mRNA expression of HOMX1.XJZ significantly inhibited the expression of IL6,PTGS2,MMP9,MMP2,and CCL2 proteins and promoted the expression of the heme oxygenase-1 protein.CONCLUSION XJZ exerts therapeutic effects against GC through multiple components,multiple targets,and multiple pathways.Our findings provide a new idea and scientific basis for further research on the molecular mechanisms underlying the therapeutic effects of XJZ in the treatment of GC.

Research Progress and Prospects of Total Factor Productivity in the Construction Industry

The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the construction industry to a higher level by scientifically and accurately measuring the total factor productivity of the construction industry and deeply analyzing the influencing factors behind it.Based on a comprehensive consideration of research methods and influencing factors,this paper systematically reviews the existing relevant literature on total factor productivity in the construction industry,aiming to reveal the current research development trend in this field and point out potential problems.This effort aims to provide a solid theoretical foundation and valuable reference for further in-depth research,and jointly promote the continuous progress and development of total factor productivity research in the construction industry.

Uridine diphosphate glucuronosyltransferase 1A1 prevents the progression of liver injury

BACKGROUND Uridine diphosphate glucuronosyltransferase 1A1(UGT1A1)plays a crucial role in metabolizing and detoxifying endogenous and exogenous substances.However,its contribution to the progression of liver damage remains unclear.AIM To determine the role and mechanism of UGT1A1 in liver damage progression.METHODS We investigated the relationship between UGT1A1 expression and liver injury through clinical research.Additionally,the impact and mechanism of UGT1A1 on the progression of liver injury was analyzed through a mouse model study.RESULTS Patients with UGT1A1 gene mutations showed varying degrees of liver damage,while patients with acute-onchronic liver failure(ACLF)exhibited relatively reduced levels of UGT1A1 protein in the liver as compared to patients with chronic hepatitis.This suggests that low UGT1A1 levels may be associated with the progression of liver damage.In mouse models of liver injury induced by carbon tetrachloride(CCl_(4))and concanavalin A(ConA),the hepatic levels of UGT1A1 protein were found to be increased.In mice with lipopolysaccharide or liver steatosis-mediated liver-injury progression,the hepatic protein levels of UGT1A1 were decreased,which is consistent with the observations in patients with ACLF.UGT1A1 knockout exacerbated CCl_(4)-and ConA-induced liver injury,hepatocyte apoptosis and necroptosis in mice,intensified hepatocyte endoplasmic reticulum(ER)stress and oxidative stress,and disrupted lipid metabolism.CONCLUSION UGT1A1 is upregulated as a compensatory response during liver injury,and interference with this upregulation process may worsen liver injury.UGT1A1 reduces ER stress,oxidative stress,and lipid metabolism disorder,thereby mitigating hepatocyte apoptosis and necroptosis.