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Background: Acquired immunodeficiency syndrome is a chronic infectious disease with high mortality and is caused by the human immunodeficiency virus (HIV). Pneumonia caused by HIV is common, but it rarely causes spontaneous mediastinal and subcutaneous emphysema. Case Presentation: A 21-year-old man with severe pneumonia was hospitalized owing to dyspnea that had been persisting for 1 day; blood test results confirmed HIV infection. Initial chest computed tomography (CT) did not reveal mediastinal or subcutaneous emphysema. However, after 21 days of treatment, the patient experienced discomfort in the neck region and experienced the feeling of snowflakes on applying pressure. Chest CT showed mediastinal and subcutaneous emphysema, located in the bilateral cervical roots, anterior upper chest wall, left axillary chest wall, mediastinum, and other parts. Metagenomic next generation sequencing (mNGS) of the sputum and blood samples suggested multiple pathogenic infections. Antiinfection treatment was initiated, and changes in the patient’s condition were monitored. The patient’s subcutaneous emphysema improved during the follow-up. Conclusion: In HIV-infected patients with sudden mediastinal and subcutaneous emphysema, mNGS can be used to determine the etiological agent during symptomatic treatment. Targeted antipathogen therapy is helpful in improving the condition of patients with subcutaneous emphysema.

Background. KLF4 and KLF5 are members of the KLF transcription factor family, which play an important role in many gastrointestinal tumors. To gain a deeper insight into its function and role, bioinformatics was used to analyze the function and role of KLF4 and KLF5 in gastrointestinal tumors. Methods. Data were collected from several online databases. Gene Expression Profiling Interactive Analysis (GEPIA), UALCAN database analysis, Kaplan-Meier Plotter analysis, LOGpc system, the Pathology Atlas, and the STRING website were used to analyze the data. We download relevant data from TCGA and then perform GO enrichment and KEGG enrichment analysis. The effects of KLF5 on gastric cancer cell proliferation were measured by CCK-8 assay. The effect of KLF5 on the expression of CyclinD1 and MMP9 was detected by Western blot. Results. KLF4 and KLF5 were differentially expressed in normal and tumor tissues of the gastrointestinal tract, and their differential expression is related to several genes or pathways. KEGG analysis showed that KLF5 was coexpressed with endocytosis-related genes. KLF5 promotes the proliferation of gastric cancer cells and the expression of metastasis-related molecules. Conclusion. KLF4 and KLF5 are of great significance for developing gastrointestinal tumors and can be used as therapeutic targets.

The particle reinforced metal matrix composites (PRMMCs) are a new kind promising materials with attracting attentions due to its superior properties such as improved strength, low density, excellent low-temperature performance and increased wear resistance. However, it was a difficult-to-cut material due to the existence of hard ceramic particles. Ultrasonic vibration-assisted machining method has attracted many attentions in machining difficult-to-cut materials. In this study, an experimental investigation was conducted on the effect of cutting and vibration parameters on the machined surface integrity of ultrasonic vibration-assisted milling in-situ TiB2/7050Al metal matrix composites. After all experiments, surface integrity such as surface roughness, residual stress, hardness and machined defects and so on were comparatively analyzed between conventional and ultrasonic vibration-assisted cutting methods. It was found that the machined surface roughness of ultrasonic vibration-assisted milling was a little larger than that of conventional milling while the compressive residual stress of the former was greater than that of the latter. It could be found that it could obtain better machined performance when vibration frequency is 30 kHz and amplitude is 4 μm in the range of given experimental parameters.

HACE1 belongs to the family of HECT domain-containing E3 ligases, which plays an important role in the occurrence, invasion and metastatic process in many human malignancies. HACE1 is a tumor suppressor gene that is reduced in most cancer tissues compared to adjacent normal tissue. The loss or knocking out of HACE1 leads to enhanced tumor growth, invasion, and metastasis; in contrast, the overexpression of HACE1 can inhibit the development of tumors. Hypermethylation reduces the expression of HACE1, thereby promoting tumor development. HACE1 can inhibit the development of inflammation or tumors via the ubiquitination pathway. Therefore, HACE1 may be a potential therapeutic target, providing new strategies for disease prevention and treatment.

This paper investigated the metallurgical phenomena of overlapping zone between two laser spots and related effects of pulse frequency (3–15 Hz) on properties of welded joints by pulsed laser welding for DP 590 steel sheets. The welded surfaces were not continuous at 3 and 5 Hz and shallow penetrations, but welded joints with full penetration were obtained at 8–15 Hz, caused by increasing average power. The microstructure evolution of fusion zone (FZ) with pulse frequency increasing was: lath martensite → lath martensite and bainite → bainite and grain boundary ferrite. When pulse frequency was 3–8 Hz, overlapping zone was divided into four areas (FZ of former spot, super-critically HAZ (SC-HAZ ), inter-critically HAZ (IC-HAZ ), sub-critically HAZ (S-CHAZ )) wherein the microstructure changed with the increase of heat input. Hardness distribution of welded surface (3–8 Hz) was in zig-zag pattern and hardness dropped in S-CHAZ and IC-HAZ owing to the different microstructures. An increasing pulse frequency led to a hardness decrease in the cross-sectional of welded joints. For the full penetration of welded joints, tensile test revealed that strength of FZ was superior compared with base metal, and Erichsen value of welded joints could reach to 80% of the base metal when pulse frequency increased to 10–15 Hz. Keywords: Dual phase steel, Laser welding, Pulse frequency, Overlapping zone, Microstructure, Properties

The differences in microstructure and mechanical properties of laser beam welded (LBW) and gas metal arc welded (GMAW) joints of 800 MPa grade Nb-Ti-Mo microalloyed C-Mn steel of 5 mm thickness were studied. The study suggested that the microstructure in welded seam (WS) of GMAW was acicular ferrite and fine grained ferrite, whereas lath martensite (LM) was obtained in WS of LBW, where inclusions were finer and did not act as nucleation sites for acicular ferrite. The microstructure of coarse-grained HAZ (CGHAZ) obtained using the two welding methods was LM and granular bainite (GB), respectively. The original austenite grain size in CGHAZ of LBW was 1/3 of GMAW. The microstructure of fine-grained HAZ and mixed-grained HAZ using the two welding methods was ferrite and M-A constituents, while that of LBW was significantly fine. The hardness of LBW welded joints was higher than the base metal (BM), which was the initiation site for tensile fracture. The tensile fracture location of GMAW welded joints was in WS. The impact toughness of LBW welded joints was excellent and the impact absorption energy was similar to BM.

Modern people spend more than 90% of their life indoors and therefore the indoor environment quality has great impact on the body health and working efficiency of human beings. A series of detectors thus been developed to evaluate the indoor environment quality. Nevertheless, these devices are either expensive or too simple. In this paper, a portable detector model, basing on the Lego Blocks Principle, is proposed. Users are able to select sensing modules according to their preference based on the precision requirements, price constraints and size limitations before piling them together like blocks to realize the multi-parameter detection. The measuring results are sent to the terminal mobile phones or remote server for future procession.

Roof greening is a promising solution for improving urban thermal environment and water quality. This paper studies the performance of a green roof with and without a self-management system, including the irrigation and shadowing subsystems, during a 3-month period via extensive experiments. Sedum plants are planted using two growing media. The first media consists of perlite and peat soil and the second media consists of average soil. Plant growth indices include vertical and horizontal growth rate as well as survival rate. Results show that a 100% survival rate can be achieved via intensive irrigation and shadowing. Meanwhile, an 8°C temperature decrease was observed during the hot season. The most suitable substrate depth is 9cm in terms of thermal effect and survival rate.

Macroscopic mechanical response is one of the key factors in designing pressure vessel. A geometric modeling of pressure vessel was established and the mesh of this modeling then generated by using the finite element simulating methods in software ABAQUS. Loading and boundary conditions of dead weight, hydraulic and uniform internal pressure which often suffered pressure vessel were set and calculated by the finite element method. Stress/strain response of pressure vessel in all kinds of alone loading ways were obtained. The results of finite element simulating were in accordance with those of theoretical calculation which provided useful data for research on mechanical response of pressure vessel under complex loading conditions.

When design program of 2D Laguerre Diagram using traditional incremental algorithm, the data structures of program is very complex and the secondary development of program is difficult, in addition, it need speed much computer memory. In order to solve the above problems, the scheme of dynamic data-exchange between hard disk data file and memory structural array is designed, which using outside file in hard disk as storage space and using structural body as intermediate variables. During the Laguerre-division against planar circle sets composed of circles have different weighted, program avoids computer memory storage restriction and implements constructing Laguerre cells aggregation effectively in random regions designed by user. Computer memory use invariable in 1MB when program run and the hard disk use is liner with the scale of Laguerre diagram. This research makes further developments towards the incremental out-of-core algorithm for Laguerre diagram. The data that store the information of Laguerre diagram are finally outputted in text file form, which makes it greatly convenient to apply the Laguerre diagram to engineering practices and secondary exploitation. At the same time, visualization module sufficed for user need that demonstrate attribute of Laguerre cells.

In order to quantify the design and simulation of various types of composite microstructure, through the Visual C++ programming language developed software 3D-ProDesign, the software for the computer to become real, complex and diverse, "mass" level three-dimensional composite material microstructure structure "samples", in the simulation process of these samples compare actual composite material component objects state , spatial orientation, spatial distribution, crystallographic orientation ,(designed can independent control of the information of the software module), and to be the microstructure of the geometric details of the simulation of an automatic forming, and can be any combination of the basic module is constructed based fiber such as polycrystalline particles enhanced composite material mixed variety of complex models of materials microstructure model, simulation model has been used in material microstructure micromechanical response calculated.

12Cr–Ni stainless steels containing different carbon contents from 0.004 wt.% to 0.034 wt.% were hot-rolled and air-cooled. Their corresponding microstructures were observed with optical microscope and transmission electron microscope, and the Vickers hardness, tensile and impact tests were also carried out. It was found that the martensitic morphology was significantly influenced by carbon content. The as-received ultra low carbon martensite in the steel containing 0.004 wt.% C is characterized by dislocation cells substructure. The formation of dislocation cells is attributed to high martensite finishing point (above 400 °C) and low interstitial atoms content. On the other hand, the martensite in the steel containing 0.034 wt.% C consists mainly of typical martensite laths because of low martensite finishing point and high interstitial atoms content which hinder dislocation motion. Furthermore, carbon content has an evident effect on the mechanical properties of 12Cr–Ni steels. The hardness and strength of the as-received steels increase with an increase in carbon content, but their elongation and impact toughness decrease with the carbon content. The steel containing 0.004 wt.% C has excellent impact toughness due to the ultra low carbon content in the martensite composed of dislocation cells.

The fine balance of T help-17 (Th17)/regulatory T(Treg) cells is crucial for maintenance of immune homeostasis. However, there is little information concerning the role played in non-small cell lung cancer (NSCLC) by Th17/Treg cells. The objective of this study was to investigate the variation of Th17 and Treg cells in the peripheral blood of patients with NSCLC. Blood samples were collected from 19 patients with NSCLC and 19 healthy donors. Samples were processed to detect CD4(+)IL-17(+) Th17 cells and CD4(+)CD25(+)Foxp3(+) Treg cells by flow cytometry, and related gene expressions were assessed by real-time quantitative polymerase chain reaction. The concentrations of interleukin (IL)-1β, IL-6, IL-10, IL-17, IL-23, and transforming growth factor-beta (TGF-β1) were also measured by enzyme-linked immunosorbent assay analysis (ELISA). The frequency of circulating Th17 cells and Treg cells was increased in samples derived from patients with NSCLC, accompanied by the upregulation of Foxp3 and RORγt. However, a negative correlation between Treg cells and Th17 cells was found in patients with NSCLC. Additionally, the Th17/Treg ratio and the related cytokines were also significantly higher in patients with NSCLC than in healthy controls. Furthermore, the frequency of Th17 cells was positively correlated with IL-1β, IL-6, and IL-23 in patients with NSCLC, and the frequency of Treg cells was positively correlated with TGF-β1 and IL-10. More importantly, the Th17/Treg ratio was positively correlated with the CEA concentrations in patients with NSCLC. Our data indicated that Th17 and Treg subset are involved in the immunopathology of NSCLC. Distinct cytokine environment might play a key role in the differentiation of the Th17 and Treg cells in NSCLC. Reconstituting an adequate balance between Th17 and Treg may be beneficial in the treatment of NSCLC.

Loading of pressure vessel was usually complicated in practical service operating conditions. Simulation model of pressure vessel was built by method of finite element simulation analysis, and structured mesh generation was realized. Numerical calculation was come true, stress/strain distribution of pressure vessel was obtained in applying of the multi-load. On this basis, this condition compared with alone applied many loadings. The calculation results indicate the validity of this model, and results are evaluated according to relevant standards, which provide a way to study mechanical response in the actual working conditions. In addition, sub-model is analyzed for key part of pressure vessel, and transition is come true from large scale simulation to small scale simulation.