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Intestinal epithelial barrier destruction occurs earlier than mucosal immune dysfunction in the acute stage of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections. At present, however, the cause of compromised gastrointestinal integrity in early SIV infection remains unknown. In the current study, we investigated the effects of SIV infection on epithelial barrier integrity and explored oxidative stress-mediated DNA damage and apoptosis in epithelial cells from early acute SIVmac239-infected Chinese rhesus macaques (Macaca mulatta). Results showed that the sensitive molecular marker of small intestinal barrier dysfunction, i.e., intestinal fatty acid-binding protein (IFABP), was significantly increased in plasma at 14 days post-SIV infection. SIV infection induced a profound decrease in the expression of tight junction proteins, including claudin-1, claudin-3, and zonula occludens (ZO)-1, as well as a significant increase in the active form of caspase-3 level in epithelial cells. RNA sequencing (RNA-seq) analysis suggested that differentially expressed genes between pre- and post-SIV-infected jejuna were enriched in pathways involved in cell redox homeostasis, oxidoreductase activity, and mitochondria. Indeed, a SIV-mediated increase in reactive oxygen species (ROS) in the epithelium and macrophages, as well as an increase in hydrogen peroxide (H2O2) and decrease in glutathione (GSH)/glutathione disulfide (GSSG) antioxidant defense, were observed in SIV-infected jejuna. In addition, the accumulation of mitochondrial dysfunction and DNA oxidative damage led to an increase in senescence-associated β-galactosidase (SA-β-gal) and early apoptosis in intestinal epithelial cells. Furthermore, HIV-1 Tat protein-induced epithelial monolayer disruption in HT-29 cells was rescued by antioxidant N-acetylcysteine (NAC). These results indicate that mitochondrial dysfunction and oxidative stress in jejunal epithelial cells are primary contributors to gut epithelial barrier disruption in early SIV-infected rhesus macaques.

Three new flavonoids, including a new prenylated aurone, 7,2′,5′-trihydroxy-8-prenylaurone (1), and two new flavanones, 2(S)-4′-hydroxy-6-methoxy-7-(2”-hydroxy-3”-methybult-3”-enyl)flavanone (2) and 2(S)-4′-hydroxy-7-methoxy-6-(1”,2”-epoxy-3”-hydroxy-dimethyl)flavanone (3), together with eight known flavonoids were isolated from the seeds of Psoralea corylifolia L. The structures were elucidated by detailed spectroscopic analysis and comparison with reported data. Among them, compounds 1 − 3, 10 and 11 exhibited inhibitory effects on the enzyme activity of DGAT1 in an in vitro assay with IC50 values ranging from 52.2 ± 1.2–89.2 ± 1.4 μM.

In this study, it was confirmed at first time that the crude extracts of Psoralea corylifolia seeds (PCE34) can reduce serum lipids (AST, ALT, TG, TC, LDL, ALP, ACP and LDH), body weight and serum sugar, increase HDL and serum insulin in hyperlipidemic wistar rat induced by high-fat diet in vivo. Furthermore, eight new chalcones 1-8, one new flavanone 12, one new coumarin 14, three new meroterpenes 15-17 and one new bakuchiol 20 together with seven known compounds (9-11, 13, 18-19 and 21) were isolated from the PCE34. Their structures were elucidated based on analyses of their spectroscopic (UV, CD, NMR and HREIMS) data. All the isolates were evaluated for in vitro inhibitory activity against DGAT1/2, PTP1B and α-Glucosidase. Among them, compounds 1-3, 8-11, 14-17, 19 and 20 were found to exhibit selective inhibitory activity on DGAT1 with IC

Recently, indefinite kernel support vector machine (IKSVM) has attracted great attention in the machine learning community as more and more indefinite metric kernel matrices have occurred. However, the existing IKSVM algorithms are usually unable to solve the problems of information redundancy and sample sparsity caused by high-dimensional data. In view of the research status, the existing mainstream IKSVM algorithms are studied.Based on the stabilization problem of IKSVM in the reproducing kernel Kre?n spaces (RKKS), this paper proves theoretically that the essence of the IKSVM is the sequential application of indefinite kernel principal component analysis (IKPCA) and support vector machine (SVM) in reduced spaces, and proposes a novel learning framework for IKSVM: two-phase indefinite kernel support vector machine (TP-IKSVM). The TP-IKSVM solves the IKSVM problem by applying IKPCA and SVM successively, combining the advantages of IKPCA in alleviating redundancy and sample sparsity caused by high-dimensional datasets and the good generalization performance of SVM in reduced spaces. Experimental results on real world datasets show the classification accuracy of TP-IKSVM is better than that of the existing mainstream IKSVM algorithms.

The coronavirus disease 2019 (COVID-19) pandemic continues to pose a global threat to the human population. Identifying animal species susceptible to infection with the SARS-CoV-2/ HCoV-19 pathogen is essential for controlling the outbreak and for testing valid prophylactics or therapeutics based on animal model studies. Here, different aged Chinese tree shrews (adult group, 1 year old; old group, 5–6 years old), which are close relatives to primates, were infected with SARS-CoV-2. X-ray, viral shedding, laboratory, and histological analyses were performed on different days post-inoculation (dpi). Results showed that Chinese tree shrews could be infected by SARS-CoV-2. Lung infiltrates were visible in X-ray radiographs in most infected animals. Viral RNA was consistently detected in lung tissues from infected animals at 3, 5, and 7 dpi, along with alterations in related parameters from routine blood tests and serum biochemistry, including increased levels of aspartate aminotransferase (AST) and blood urea nitrogen (BUN). Histological analysis of lung tissues from animals at 3 dpi (adult group) and 7 dpi (old group) showed thickened alveolar septa and interstitial hemorrhage. Several differences were found between the two different aged groups in regard to viral shedding peak. Our results indicate that Chinese tree shrews have the potential to be used as animal models for SARS-CoV-2 infection.

Intestinal biopsy is a basic experimental method for studying pathological changes in the intestinal tract during human immunodeficiency virus (HIV) infection. In this study, jejunal resection and anastomosis were successfully performed in 12 Chinese rhesus macaques (Macaca mulatta). The sampled gut tissues were then examined by hematoxylin and eosin (H&E) staining, electron microscopy, flow cytometry, immunofluorescence detection, and RNA quality analysis to ensure suitability for histological, physiological, pathological, and immunological detection, as well as mechanistic analysis at the cellular and molecular level. Importantly, the surgery did not affect the ratio or number of immune cells in peripheral blood or the concentration of lipids, proteins, and vitamins in plasma, which are important indicators of nutritional status. Our results thus indicated that jejunal resection and anastomosis are feasible, and that immune homeostasis and intestinal barrier integrity are not altered by surgery. All macaques recovered well (except for one), with no postoperative complications. Therefore, this animal surgery may be applicable for longitudinal intestinal research related to diseases such as acquired immunodeficiency syndrome (AIDS).

Background KIF23 is a member of kinesin family, recent researches indicate KIF23 plays an important role in the proliferation and migration of malignant cancer cells. While the function and specific molecule mechanism of KIF23 in triple negative breast cancer remains unclear. Methods QRT-PCR and immunohistochemistry were conducted to analyze expression of KIF23 in triple negative breast cancer tissues and paired paracancer tissues. CCK-8 assay, colony formation assay, wound healing assay and transwell assay were applied for exploring phenotype changing of triple negative breast cancer cell lines MDA-MB-231 and BT549 after siRNA-induced knockdown of KIF23. Several bioinformatic databases were used for predicting miRNAs that combing with KIF23 mRNA and verified by dual luciferase reporter assay. Western blot assay was performed to explore downstream signaling pathway of KIF23. Results KIF23 was overexpressed in triple negative breast cancer, knockdown of KIF23 by siRNA inhibited proliferation and migration of TNBC cell lines MDA-MB-231 and BT549. Mechanistically, knockdown of KIF23 resulted in the suppression of Epithelial-Mesenchymal Transition. Meanwhile, miR-195-5p was downregulated in TNBC, and dual luciferase reporter assay indicated miR-195-5p could combine with 3'UTR of KIF23 thus promoting degradation of KIF23. Conclusions KIF23 is a potential oncogene in triple negative breast cancer, miR-195-5p could combine with 3'UTR of KIF23. Our study reveals a new sight into triple negative breast cancer.

The research can be used to generate animal models of severe disease based on the hACE2 mice for development of treatment against severe COVID-19 and also quickly establish specific mouse models in response to other emergency situations in the future.

After the public health emergency, it has promoted the development of the flexible work system of public officials, accelerated the ability of public officials to respond quickly and arrange work tasks flexibly in the "epidemic situation", and accelerated the pace of improving the flexible work system of public officials in China. It is of great significance to study the experience and deficiency of the flexible working system of public officials in the epidemic situation. Therefore, based on the flexible work system, this paper studies the scope and limitations of the implementation of the flexible work system for public officials in the "epidemic" in China, and further puts forward suggestions for the improvement of the flexible work system in the "epidemic" public sector. With the novel coronavirus infection pneumonia prevention and control work ongoing, party and government organs and institutions began to implement flexible work system. According to the spirit of the notice of the general office of the State Council on extending the Spring Festival holiday in 2020 (Guo Ban Fa FA Dian [2020] No. 1), all kinds of financial institutions and financial infrastructure related institutions will go to work normally from February 3, 2020.According to the notice, all units can implement flexible work system, flexibly adjust the rest time, take rotation and wrong time to work, or use the network office mode to work at home, so as to reduce the number of people as much as possible. During the period of "epidemic", the flexible working system adopted by the public sector is a new management method adopted by the government.

Microbial translocation is a cause of systemic immune activation in HIV/SIV infection. In the present study, we found a lower CD8+ T cell activation level in Macaca leonina (northern pig-tailed macaques, NPMs) than in Macaca mulatta (Chinese rhesus macaques, ChRMs) during SIVmac239 infection. Furthermore, the levels of plasma LPS-binding protein and soluble CD14 in NPMs were lower than those in ChRMs. Compared with ChRMs, SIV-infected NPMs had lower Chiu scores, representing relatively normal intestinal mucosa. In addition, no obvious damage to the ileum or colon epithelial barrier was observed in either infected or uninfected NPMs, which differed to that found in ChRMs. Furthermore, no significant microbial translocation ( Escherichia coli) was detected in the colon or ileum of infected or uninfected NPMs, which again differed to that observed in ChRMs. In conclusion, NPMs retained superior intestinal integrity and limited microbial translocation during SIV infection, which may contribute to their lower immune activation compared with ChRMs.

Emerging evidence indicates that loss of inhibitory tone in amygdala with its subsequent overactivation contributes to the development of multiple mental disorders such as anxiety disorders and post-traumatic stress disorder (PTSD). Harmine is a member of natural β-carboline alkaloids which can readily cross the blood brain barrier and displays significant antidepressant and anxiolytic effects in rodents. However, the underlying neurobiological mechanisms are largely unknown. Here, by using whole-cell patch clamp recordings in in vitro amygdala slices, we examined the effect of harmine on glutamatergic and GABAergic transmission onto basal amygdala (BA) projection neurons (PNs). Our results showed that harmine affected neither the amplitude nor the frequency of spontaneous and miniature excitatory postsynaptic currents (sEPSCs/mEPSCs) of PNs. By contrast, it markedly increased both the amplitude and frequency of the spontaneous inhibitory postsynaptic currents (sIPSCs). For mIPSCs, only an increase of their frequency but not amplitude was observed following harmine perfusion, suggesting that harmine might act through presynaptic mechanism. In parallel, a reduction of paired-pulse ratio of evoked IPSCs emerged in the presence of harmine. Furthermore, the intrinsic excitability of PNs was dramatically decreased upon harmine treatment. Together, our study suggests that harmine selectively potentiates the inhibitory but not excitatory transmission onto BA PNs, which may contribute to its antidepressant and anxiolytic influence.

Evolution of the radial perturbed magnetic field with radius at different plasma pressures and viscosities is studied by using Fourier transforms and Finite difference method. The main conclusions are that the effect of lower plasma pressure on radial perturbed magnetic fields is not evident. Higher plasma pressure has obvious effect on longer waves; however, shorter waves were affected by lower plasma pressure obviously. The maximum values of radial perturbed magnetic fields increase with the increase of plasma viscosities which indicates plasma viscosity cannot be neglected in the precise calculation.

Pressure distribution in heavy oil reservoir was numerical simulated by calculating varying-coefficients Darcy’s equation with boundary element method (BEM) in this paper. Permeability coefficients of Darcy’s equation at different parameters were numerical simulated firstly. Then the pressure contours of nine-spot pattern were given. The simulated results show that the particle shape coefficient and kinematic viscosity have major impact on permeability coefficient. In addition, the influence of permeability coefficient on seepage pressure is obvious. Numerical simulated results can provide quantitative theoretical basis for the well deployment and production estimation in the heavy oil exploitation. The reasonable numerical results indicate that the BEM is effective in dealing with heavy oil seepage problems.

OBJECTIVES Recombinant tissue plasminogen activator (rt-PA) is a safe and effective treatment for acute brain ischemia stroke, albeit with a narrow therapeutic window. We aimed to assess the effect of epigallocatechin gallate (EGCG) in extending the rt-PA treatment window in this clinical trial among stroke patients. METHODS Patients were randomly assigned according to their onset-to-treatment time (OTT) and were then treated with rt-PA simultaneously with EGCG or placebo. Treatment outcome was assessed by the National Institutes of Health stroke scale (NIHSS) and plasma levels of matrix metalloproteinases (MMP)-2 and 9. RESULTS Administration of EGCG significantly improved treatment outcomes of patients in the delayed OTT strata, as evidenced by improved NIHSS scores. This improved treatment outcome was likely attributed to reduction in plasma levels of both MMP-2 and 9, as indicated by strong linear correlations between both MMPs and NIHSS scores in all patients. CONCLUSIONS Epigallocatechin gallate could potentially be used as a supplement of traditional rt-PA treatment among stroke patients, particularly those with delayed OTT, to extend the otherwise narrow therapeutic window and improve the outcome in late stroke treatment.

Little data are available on polycyclic aromatic hydrocarbons (PAHs) in marine fish associated with oil and gas activities from the South China Sea (SCS). Twenty-one wild marine fish species from the northern South China Sea were collected for analysis of the presence of polycyclic aromatic hydrocarbons (PAHs). The total concentration of the PAHs (∑16PAHs) ranged from 199 to 606 ng·g−1 d.w., indicating moderate contamination. PAHs in fish species found in the Pearl River Delta (PRD) were significantly higher than those from the Yachen (YC) gas fields (p

Heavy metal concentrations were measured in 29 marine wild fish species from the South China Sea. Concentrations (wet weight) were 0.51-115.81 ng/g (Cd), 0.54-27.31 ng/g (Pb), 0.02-1.26 μg/g (Cr), 8.32-57.48 ng/g (Ni), 0.12-1.13 μg/g (Cu), 2.34-6.88 μg/g (Zn), 2.51-22.99 μg/g (Fe), and 0.04-0.81 μg/g (Mn), respectively. Iron concentrations in all and Mn in some fish species were higher than the acceptable daily upper limit, suggesting human consumption of these wild fish species may pose a health risk. Human health risk assessment, however, indicated no significant adverse health effects with consumption.

2195 Al–Li alloy was processed by solid solution heat treatment and then aged at different temperatures, and its microstructure, mechanical properties, inter-granular corrosion (IGC), exfoliation corrosion (EXCO) and stress corrosion cracking (SCC) behaviors were observed and determined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), immersion test in IGC and EXCO solutions, electrochemical impedance spectroscopy (EIS) and slow strain rate tensile (SSRT) test. The results reveal that the size and density of T1 precipitates at grain boundary are increased with increasing aging temperature whereas the density of T1 phases in grain is increased firstly and then reduced slightly. The IGC and EXCO susceptibility of 2195 alloy is increased while its SCC susceptibility in 3.5% NaCl solution is low and hardly influenced by the aging temperature. The hardness and tensile strength are increased at first and then decreased, but the elongation and static toughness values are declined with aging temperature. The optimum heat treatment for the practical application of 2195 alloy is the aged at 155 °C for 14 h temper.

The pitting corrosion behaviors of 7A60 aluminum alloy in the retrogression and re-aging (RRA) temper were investigated by electrochemical impedance spectroscopy (EIS) and electrochemical noise (EN) techniques, and the microstructure and the second phase content of the alloy were observed and determined by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The results show that there exist two different corrosion stages for 7A60 alloy in 3.5% NaCl solution, and the corrosion process can be detected by the appearance of EIS spectrum with two capacitive time constants and the wavelet fractal dimension D extracted from EN. SEM and EDS results also demonstrate that severe pitting corrosion in 7A60 alloy is mainly caused by electrochemical active MgZn2 particles, secondly by Al2MgCu and Mg2Si. Al7Cu2Fe particles make little contribution to the pitting corrosion of 7A60 alloy.

Al-Si coating in different hot dip process conditions were made by a hot-dip galvanizing simulator, and distribution regularities of chemical elements in coating were studied by means of GDS, SEM, EDS and XRD. The results show that the hot dip temperature has no obvious impact on elements distribution in coating, but has some impact on Si content in surface coating. The hot dip time has no obvious impact on surface coating element content, but has distinct impact on deep coating element content. With the hot dip time increasing, Al content decreases, Fe content increases, and Si content decreases. Al-Si coating is composed of 3 layers, surface layer contains fine and close Al2O3 film, which has good anti-oxidation property on high temperature and hot stamping property, middle layer contains high melting point phase ,such as rich Fe phase , FeAl3 ,which has excellent anti-oxidation property on high temperature. The elements in diffusion layer can even be transited to basic steel, so coating has good adhesion property.

RFID (Radio Frequency Identification) is a non-contact automatic identification technology, without human intervention. It is convenient to apply and it can identify fast moving objects. Around the tool and the tool information, the problem of low operational efficiency and low degree of tool management information are still unsolved. In this paper, RFID technology is applied in the tool automatic identification and management system. The tool automatic identification and database management system based on RFID is built. The application model, tool information database design and Upper Computer management software of the RFID in tool identification and management are analyzed. The overall architecture and the software function module of the system are constructed. The database management system is developed by the LabVIEW software. The interface design between LabVIEW and Access database is completed by using ActiveX, as a result, the information of Access database can be written-in and read-out by the management system. Meanwhile, the communication protocol between the Upper Computer and Lower Computer is programed that based on VISA. The RS232 is applied to make the communication between the Upper Computer and Lower Computer come true. Finally, take the SECO's Solid Carbide Ball-end Milling Cutter as an example to have an experiment. Through the experiment, the system proved to be with high reliability and efficiency.

Nickel-base superalloy GH4169 is a kind of alloy with high intensity, heat-stability and heat-fatigability, so that is often used to aerospace field, but which has poor machinability. The cutting force, plasticity deformation all present their particular characters which causes cutting vibration . The cutting vibration influence the surface roughness, the swing of the cutting force and tool wear. This article discusses the superalloy of GH4169 on the basis of cutting speed, cutting depth and feed per-tooth.

This paper explores the drilling characteristics of GH3039 supper alloy. The machining of GH3039 is a difficulty which is commonly used in aircraft and engineer components of the aerospace industry. The spindle speed and feed per tooth are the major influence factors which are studied to gain large removal rate and predict the drilling characteristics. So the single factor test is carried out about spindle speed and feed per tooth. The results of the experiment show that the drilling force of GH3039 decreased with the increasing of spindle speed up to 900r/min which is larger than other metal drilling process. The small feed per tooth may obtain small drilling force. So too low spindle speed and large feed per tooth are not adopted in the GH3039 drilling process. The analysis of the chip formation also verifies the above characteristics. At the same time, the serious serrated chip is occurred which is adverse for the drilling. It has significant for other supper alloy real drilling process.

We proposed a distributed broadcast algorithm which is based on master/slave dominator partition, it not only guarantees the full coverage of the network, but also has better scalability. In our algorithm, each node first selects its connected domination set (CDS) from its two hop neighbor graph, then partitions the domination nodes into master and slave dominators, master dominators forward the broadcast packet, slave dominators monitor the network coverage and forward the broadcast packet when necessary.

We proposed a maximum concurrent network flow based channel assignment algorithm (MCFCA) for wireless networks. In the MCFCA algorithm, we first use the maximum concurrent network flow algorithm to compute the maximum network capacity, then we assign each link a priority according to its link throughput, finally the channel is assigned to minimize the interference between neighbor nodes in the priority order. Performance simulation shows its effectiveness in channel assignment.

Amygdala activation is known to be critical for the processing of stressful events in brain. Recent studies have shown that the projection neurons (PNs) in amygdala, although architecturally intermingled, are integrated into distinct microcircuits and thus play divergent roles in amygdala-related behaviors. It remains unknown how stress regulates the individual amygdala PNs embedded in distinct microcircuits. Here, by using retrograde tracing and electrophysiological recording in in vitro slices, we explored the modulation of acute immobilization stress (AIS) on the basoamygdala (BA) PNs projecting either to medial prefrontal cortex (mPFC) or elsewhere, which we designated as BA-mPFC and non-BA-mPFC PNs respectively. The results showed that in the control mice, both the excitatory and inhibitory postsynaptic currents (sEPSCs/sIPSCs) were comparable between these two subsets of BA PNs. The influences of AIS on sEPSCs and sIPSCs were overall similar between the two neuronal populations. It markedly increased the sEPSCs amplitude but left unaltered their frequency as well as the sIPSCs amplitude and frequency. Despite this, several differences emerged between the effects of AIS on the distribution of sEPSCs/sIPSCs frequency in these two groups of BA PNs. Similar changes were also observed in the sEPSCs/sIPSCs of the two PN populations from mice experiencing forced swimming stress. Their intrinsic excitability, on the other hand, was nearly unaltered following AIS. Our results thus suggest that acute stress recruit both BA-mPFC and non-BA-mPFC PNs mainly through enhancing the glutamatergic transmission they receive. Electronic supplementary material The online version of this article (doi:10.1186/s13041-016-0283-6) contains supplementary material, which is available to authorized users.

The present study was conducted on sensitized 304 stainless steels in 0.5mol/L Na2S2O3solution under the slow strain rate testing (SSRT). To monitor the evolution of intergranular stress corrosion cracking (IGSCC) occurring, acoustic emission (AE) technology was applied in this test. Besides, signal characteristics of different AE sources, including the dissolution along susceptible grain boundaries, the plastic deformation ahead of the crack tip and the mechanical fractures of material ligaments, were identified distinctly with fractography and clustering analysis.

The pressure on bearing’s surface in the dislocated single floating ring bearing with different radius of floating ring (Rf) and velocity of floating ring (Uf) were simulated by boundary element method (BEM). The numerical results indicate that the pressure on bearing increases with the increases of Ufwhen displacement of bearing (DR) is fixed. The pressure on bearing increases with the increases of Rfwhen DR is fixed. The pressure on bearing increases with the increases of DR when Rfis fixed.

7A60 aluminum alloy was treated under different retrogression time, and the micro-structure, mechanical properties and stress corrosion behaviors were observed and determined by optical microscopy, transmission electron microscopy and slow strain rate tester. The results shown that with the increasing of retrogression time the precipitates within the grains were gradually grown up, and the precipitates along the grain boundaries were changed from small and closely spaced into coarse and widely spaced ones. The elongation and toughness ratio of 7A60 alloy increased obviously with the retrogression time, whereas the tensile strength and hardness of 7A60 alloy decreased. The optimum retrogression time is about 60min, under which 7A60 alloy has a best combination of tensile strength, ductility and stress corrosion resistance.

The evolution of growth rate and eigenfunction of kink instability in a cylindrical plasma column with different plasma pressure is studied by a semi-analytical method. The method can transform magnetohydrodynamics (MHD) equations into a second-order ordinary differential equation. Growth rate can be obtained by solving the second-order ordinary differential equation. 2-D radial eigenfunction can be calculated with a fixed growth rate. The significant change of growth rate and eigenfunction indicates inhomogeneous plasma pressure P0 is destructive for kink instability. The advantage of our method is that it can divide problem into two parts and then solve them separately.

Indium tin oxide (ITO) films were fabricated on polyethylene terephthalate (PET) substrate at room temperature using dc magnetron sputtering technique with different sputtering powers. The structural, electrical and optical properties were investigated by X-ray diffraction (XRD), Hall effect, reflection and transmission, respectively XRD patterns show gradual enhancement of crystalline quality with increasing sputtering power. Significant improvement of Hall mobility due to the reduction of defects was observed though the carrier density varied slightly. Simultaneously, the mean transmission in visible light range decreased severely with increasing sputtering power. Slight move toward shorter-wavelength side of absorption peak was due to the variation of plasma wavelength. The reflection increase of near-infrared light originated from the decrease of resistivity. Finally band gap was obtained using Tauc's relation and it was consistent with Burstein-Moss shift.

To select reasonable cutting parameters, improve the processing surface quality, and extend the tool life, this paper uses four solid carbide end milling tools to process TC4 titanium alloy, and analyses the influence of the difference cutting parameters and the geometric angles to chip shape. The experiment results indicate that the degree of serrated chip shape is increased by increasing the feed rate under the condition of certain spindle speed. But the degree of serrated chip shape may be decreased by the adoption of small axial and radial depth, or bigger rake angle and smaller helix angle. Select larger rake angle, cutting edge is sharp, the metal deformation of cutting layer is small, which can reduce the friction force when chip flowing through the tool rake face, so that the cutting force and cutting temperature decreases accordingly.The greater the helix angle is, the worse the chip removal conditions is, and the degree of serrated chip becomes larger, the blade is more sharp, easily crack, and the tool life decreases. So relatively small helix angle is better. The choice of angles is interrelated with each other, the selection of some angle separately cannot get the desired reasonable value.

The porous Cu film was deposited on soft PVDF substrate by magnetron sputtering at different sputtering pressure. The microstructure and electrical properties of Cu films were investigated as a function of sputtering pressure by X-ray diffraction XRD and Hall effect method. The results show that the surface morphology of Cu film is porous, and the XRD revealed that there are Cu diffraction peaks with highly textured having a Cu-(220) or a mixture of Cu-(111) and Cu-(220) at sputtering pressure 0.5 Pa. The electrical properties are also severely influenced by sputtering pressure, the resistivity of the porous Cu film is much larger than that fabricated on Si substrate. Furthermore, the resistivity increases simultaneously with the increasing of Cu film surface aperture, but the resistivity of Cu film still decreases with the increasing grain size. It can be concluded that the crystal structure is still the most important factor for the porous Cu film resistivity.

The tool geometric angle and cutting parameters have a significant influence on the titanium alloy milling process by the usage of solid carbide end mills.The physical simulation method was applied to predict the cutting force and temperature by using two comparative sets of simulation data such as the different tool gemetric angle as tool rake angle, helix angle and different cutting parameters such as spindle speed, axial depth of cut, radial depth of cut. Thus are the commonly used methods to simulate and predict the cutting process before the actual production, which can reduce product cost and time.

The mechanical properties of flat end mill is analyzed the high-speed milling, the linear model for milling force is established. And the 2A70 aluminum alloy four-factor four-level orthogonal milling tests are carried out, the nonlinear model of milling is set up by using regression analysis method. The comparative analysis is made between the linear model and nonlinear model, whose results show that the two models have good agreement on the value and trend of change, which is the basis of the follow-up tool path optimization, fault diagnosis and so on.

In this study we investigated 745 specimens of purpleback flying squid Sthenoteuthis oualaniensis across a large distribution range to investigate geographic, intraspecific and sexual variations in beak morphology. Beak morphometric variables showed significant spatial and intraspecific differences (P

Au/NiCr/Ta multi-layered metallic films were deposited on Al2O3 substrate by magnetron sputtering at different substrate temperature. The effect of substrate temperature on magnetron sputtering Au/NiCr/Ta films in crystal orientation, residual stress and resistivity was investigated. The all magnetron sputtering films were highly textured with dominant Au-(111) orientation or a mixture of Au-(111) and Au-(200) orientation. The residual stress in magnetron sputtering films at different substrate temperature was tensile stress with 155MPa-400MPa. A smallest resistivity of 3.6µΩ.cm was obtained for Au/NiCr/Ta multi-layered metallic films at substrate temperature 180°C. The experiment results reveal that the resistivity increased with the increase of the residual stress of metallic films.

A data fusion algorithm was established for estimating the state of target tracking system with multi-type sensor. Through Kalman filter regarding the multi-sensors to computer goal estimated value, it can obtain estimation value of goal at moment. And mean square deviation of fusion estimation value was smaller than single sensor's mean square deviation. The simulation results indicated that synchronisms data fusion method was effective to the multi-target tracking problem. Asynchronous multi-sensor fusion process can obtain good control effect in the practice control process.

According to the condition of the high speed milling aluminum (al) blades, the wear characteristics of the carbide tool was observed, whose wear characteristics mainly were flank wear, micro-tipping, exfoliation and so on. With the increase of the cutting time, the tool wear became larger according to the increment of the spindle speed. At the condition of the same feed per tooth, applying high speed finish milling for al alloy blades whose cutting efficiency increased remarkably, surface roughness decreased, high speed machining was adopted in real applications to achieve high economical benefits.