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The welding tool is the key of micro friction stir welding (μFSW), which affects the heat input and the plastic forming of weld metal. In this paper, 0.8-mm-thick ultra-thin 1060-H24 aluminum sheets μFSW butt joints were used to compare and analyze the influence of the conventional tool and shoulderless tool on weld shaping, microstructure and mechanical properties. Besides, by measuring the axial force, transverse force and weld temperature in μFSW process, the influence of these two different tools on the heat input and metal flow mechanism of the weld were analyzed. The results show that the weld generated by the shoulderless tool has narrower width, less heat input and metal involved in plastic forming resulting in smaller HAZ (heat affected zone). The hardness of NZ (nugget zone) is obviously increased compared with that of the base metal. The highest tensile strength can reach 108.6 MPa, accounting for 78.6% of the base metal and 117.3% of the joint by the conventional tool. But the welding defects have to be overcome for industrial application of the shoulderless tool.

Emerging evidence has linked the dysregulation of [N.sup.6]-methyladenosine ([m.sup.6] A) modification to inflammation and inflammatory diseases, but the underlying mechanism still needs investigation. Here, we found that high levels of [m.sup.6]A modification in a variety of hyperinflammatory states are p65-dependent because Wilms tumor 1-associated protein (WTAP), a key component of the 'writer' complex, is transcriptionally regulated by p65, and its overexpression can lead to increased levels of [m.sup.6]A modification. Mechanistically, upregulated WTAP is more prone to phase separation to facilitate the aggregation of the writer complex to nuclear speckles and the deposition of [m.sup.6]A marks on transcriptionally active inflammatory transcripts, thereby accelerating the proinflammatory response. Further, a myeloid deficiency in WTAP attenuates the severity of LPS-induced sepsis and DSS-induced IBD. Thus, the proinflammatory effect of WTAP is a general risk- increasing mechanism, and interrupting the assembly of the [m.sup.6]A writer complex to reduce the global [m.sup.6]A levels by targeting the phase separation of WTAP may be a potential and promising therapeutic strategy for alleviating hyperinflammation., Introduction Inflammation is usually a physiological healing response that is triggered by noxious stimuli and conditions such as infection and tissue injury (1). Moderate inflammation is essential for pathogen clearance, [...]

Combining with movement theory of fire smoke flow of mine roadway and effect of fire-air pressure to ventilation network, the paper proposed mathematical model of numerical simulation and computer algorithm of smoke expansion in time of mine fire, and determined reasonable routes for avoiding disaster. Based on basic information platform of 3DGIS digital mine and 3D visualization technique, computer programs of algorithm of smoke movement and route for avoiding disaster were developed, and it can simulate process of fire disaster in mine and show the scope of smoke pollution and routes for avoiding disaster for workers. The algorithm can be applied to analyze smoke flow expansion of actual fire disaster confirmed by experiment of roadway physical miniatures. The program was applyed to fire emergency plans drills of a coal mine, and played a very good role and achieved a good result.

【Abstract】Objective: To analyze the injuries of motorcyclists involved in fatal motorcycle frontal crashes. Methods: A survey group involving multi-discipline experts was built to randomly collect data on fatal motor-cycle frontal collision accidents that occurred in Chongqing during 2006-2010. The sampled information included medi-cal or autopsy reports, blood alcohol concentration (BAC) level, helmet use, accident witness, field sketch as well as field photos. The motorcyclist injuries were scored accord-ing to the Abbreviated Injury Scale (AIS) 2005. The involved riders with a BAC level≥20 mg/ml were attributed to alco-hol use. Data were processed statistically with nonparamet-ric test via software SPSS 11.0. Results: A total of 86 fatal motorcycle frontal crashes were sampled and further analyzed. The age of motorcy-clists enrolled in this investigation showed nominal distri-bution and the middle-aged (30-39 years) occupied the high-est percentage of fatalities. There were only 14 motorcyclists (16.3%) wearing helmets at the moment of collision. And 12.8% of these motorcyclist crashes were attributable to alcohol use. Impact injury was the main fatal cause, accounting for 72% of motorcyclist deaths, followed by tumbling injury (26%) and run-over (2%). Respectively 84%, 22% and 19% of motorcyclists who sustained head, chest and abdominal trauma died. Extremity injury was the most frequently ob-served injury type. Conclusions: This investigation is helpful to build accident prevention programs and develop protection de-vices which may effectively mitigate injuries and prevent deaths following motorcycle frontal collision accidents. Further investigations on motorcycle collision accidents are still needed. Key words: Motorcycles; Mortality; Accidents, traffic; Wounds and injuries

CO2 injection to strengthen shale gas development is a new technology to improve shale gas recovery and realize geologic sequestration. Many scholars have studied these aspects of this technology: mechanism of CO2 displacement CH4, CO2 and CH4 adsorption capacity, affecting factors of shale adsorption CO2, CO2 displacement numerical simulation, and supercritical CO2 flooding CH4 advantages. Research shows that CO2 can exchange CH4 in shale formations, improve shale gas recovery, on the other hand shale formations is suitable for CO2 sequestration because shale gas reservoir is compact. The supercritical CO2 has advantages such as large fluid diffusion coefficient, CO2 dissolution in water to form carbonic acid that can effectively improve the formation pore permeability etc., so the displacement efficiency of supercritical CO2 is high. But at present the technology study mainly focus on laboratory and numerical simulation, there is still a big gap to industrial application, need to study combined effect of influence factors, suitable CO2 injection parameter in different shale gas reservoir, CO2 injection risk and solutions etc.

In response to the increasing traffic noise problem, we designed a combined acoustic metamaterial (CAM) based on the multi-channel Fano resonance principle. By utilizing the Fano resonance coupling between the acoustic spiral structure and the hollow structure, efficient sound insulation under effective ventilation conditions is achieved. Simulation results of acoustic transmission loss show that the acoustic transmission loss of CAM is more than 13 dB in the frequency band of 520–989 Hz. The broadband sound insulation characteristic can block the oblique angle incident sound waves from different angles. Simulation results of the elastic strain energy and acoustic pressure field validate the sound insulation mechanism of the Fano resonance of the combined acoustic metamaterial. The experimental results in the impedance tube generally agree with the simulation results. To explore the possibility of wider engineering applications of CAM, we propose a combined CAM and CAM0.7 structure. The results show that a series structure of acoustic metamaterials can be selected to further realize broadband sound insulation within 500–1574 Hz. [ABSTRACT FROM AUTHOR]

Human metallothionein-2A (MT2A) protein participates in metal homeostasis, detoxification, oxidative stress reduction, and immune defense. It decreases heavy metal ions and reactive oxygen species (ROS) during injury of cells and tissues. The single nucleotide polymorphisms at the MT2A gene have been associated in various human diseases including cancer. The current study aimed to elucidate associations between MT2A genotypes with the clinical, biochemical, and molecular characteristics that potentially related to lowered MT2A ex-pression. One hundred and forty-one healthy Taiwanese subjects were enrolled from Changhua Show-Chwan Memorial Hospital. Clinical, biochemical and molecular characteristics including the frequent minor allele SNPs, rs28366003 and rs10636, within the MT2A gene were determined. The genotype distribution of MT2A rs10636 fits the Hardy-Weinberg equilibrium. The significant associations with gradually decline of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were identified with MT2A rs10636 and rs28366003 using analysis of variance (ANOVA) with Tukey's analysis as a post hoc test. We further validated the correlations between the expressions of genes in erythropoiesis, cholesterol synthesis, platelet synthesis, insulin with MT2A using the web-based Gene Expression Profiling Interactive Analysis (GEPIA) databases. The results revealed that hypoxia-inducible factor 1α (HIF-1α), erythropoietin (EPO), lipoprotein lipase (LPL), and lecithin-cholesterol acyltransferase (LCAT) mRNA ex-pression are significantly correlated with MT2A mRNA expression. In conclusion, these results suggested that genetic variations of MT2A rs10636 and rs28366003 might be an important risk factor for erythropoiesis in the Taiwanese general population.

The main objective of this study is to measure the distribution of machining stress by the instrumented indentation test (IIT). Finite element method (FEM) was performed to investigate the influences of tensile stress and compression stress on the indentation response (Load-displacement curves, average contact pressure and contact area). The thicknesses of machining stress layer under turning and grinding processing ways were obtained by layer stripping method based on instrumented indentation technique. Results indicate that the machining stress brings complex stress state. Under the same load, the corresponding indentation displacement increases while the indentation plastic work, contact area and average contact pressure decrease with the increases of machining stress (from compressive stress to tensile stress). Tensile stress does just the opposite. In addition, the layer thicknesses of the machining stress for turning and grinding members were measured by instrumented indentation method, results agree with X-ray method and demonstrate the effectiveness of the proposed approach.

Rainfall has a significant impact on urban population mobility, posing great challenges to traffic management and urban planning. An understanding of this influence from multiple perspectives is urgently needed. In this study, we devised a multiscale comparative research framework to explore the spatiotemporal effects of rainfall on taxi travel patterns, aiming to provide a new perspective on the investigation of rainfall's impact on urban human mobility. More specifically, at the macroscopic scale, we computed taxi travel indicators across the entire study area and used kernel density estimates to observe the spatiotemporal distribution patterns influenced by rainfall. Subsequently, complex traffic networks were constructed by considering urban road intersections as nodes and combined with visualization methods to understand changes in taxi travel patterns visually at the microscopic level. We selected Wuhan City, a typical urban area in southern China with frequent rainfall, as the study area and used meteorological data along with a large volume of taxi spatiotemporal trajectory data for investigation. Results indicated a 4.16% decrease in weekly travel volume due to rainfall, with a 3.96% decrease on workdays and a 4.64% decrease on weekends. However, nighttime rainfall between 19:00 and 22:00 on weekdays increased the demand for taxi travel. Furthermore, the impact of rainfall on weekends exceeded that on workdays, restricting people's mobility and leisure activities, resulting in reduced travel to recreational tourist spots and commercial pedestrian streets. Rainfall altered residents' travel preferences to some extent, with more residents choosing taxis during rainy weather, which led to decreased transportation efficiency and increased traffic congestion. These findings contribute to a deeper understanding of the complex relationship between population mobility patterns and the urban ecological environment, providing valuable insights for planning resident travel and taxi dispatching under adverse weather conditions., Author(s): Rong Chen [1]; Lingjia Liu (corresponding author) [1]; Yongping Gao [2] 1. Introduction The city embodies a complex system where humans navigate, interact with urban infrastructure, and generate a [...]