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In powderswith different contents (0.5−10 wt.%)were melted into the Sn−3.0Ag−0.5Cu (SAC305) solder to change the microstructure and thus improve the properties of the solder. The results showed that β-Sn(In), Ag3(Sn,In) and Cu6(Sn,In)5phases existed in all the In-added solders, and an additional phase of InSn4was found in the SAC305−10In solder. With increasing In addition amount, the β-Sn nucleation sites were increased and the nucleation model was changed from {101} to {301}, which refined the β-Sn grains and transformed the β-Sn morphology from large grains to interlaced grains and finally to multiple grains. As a result, a combined effect of fine grain strengthening and solid solution strengthening was achieved to increase the microhardness of the SAC305−xIn solders with increasing In addition amount.

Objective: Intervertebral disc degeneration (IVDD) is a major cause of morbidity and disability. Our study aimed to investigate the potential of cartilage oligomeric matrix protein (COMP) and ADAMTS7 (A disintegrin and metalloproteinases with thrombospondin motifs 7) as biomarkers for IVDD together with their functional relationship. Methods: IVD tissues and peripheral blood samples were collected from IVDD rabbit models over 1–4 weeks. Tissues and blood samples were also collected from clinical patients those were stratified into four equal groups according to Pfirrmann IVDD grading (I–V) with baseline data collected for each participant. COMP and ADAMTS7 expression were analyzed and biomarker characteristics were assessed using linear regression and receiver operating curve (ROC) analyses. Results: COMP and ADAMTS7 expression increased in tissues and serum during IVDD progression. Serum COMP (sCOMP) and serum ADAMTS7 (sADAMTS7) levels increased in a time-dependent manner following IVD damage in the rabbit model while significant positive correlations were detected between sCOMP and sADAMTS7 and Pfirrmann grade in human subjects. ROC analysis showed that combining sCOMP and sADAMTS7 assay results produced an improved diagnostic measure for IVDD compared to individual sCOMP or sADAMTS7 tests. In vitro assays conducted on human cell isolates revealed that COMP prevented extracellular matrix degradation and antagonized ADAMTS7 expression although this protective role was uncoupled under microenvironmental conditions mimicking IVDD. Conclusions: Increases in circulating COMP and ADAMTS7 correlate with IVDD progression and may play regulatory roles. Assays for sCOMP and/or sADAMTS7 levels can discriminate between healthy subjects and IVDD patients, warranting further clinical assessment.

The deubiquitinase cylindromatosis (CYLD) functions as a tumor suppressor inhibiting cell proliferation in many cancer types including melanoma. Here we present evidence that a proportion of melanoma cells are nonetheless addicted to CYLD for survival. The expression levels of CYLD varied widely in melanoma cell lines and melanomas in vivo, with a subset of melanoma cell lines and melanomas displaying even higher levels of CYLD than melanocyte lines and nevi, respectively. Strikingly, although short hairpin RNA (shRNA) knockdown of CYLD promoted, as anticipated, cell proliferation in some melanoma cell lines, it reduced cell viability in a fraction of melanoma cell lines with relatively high levels of CYLD expression and did not impinge on survival and proliferation in a third type of melanoma cell lines. The decrease in cell viability caused by CYLD knockdown was due to induction of apoptosis, as it was associated with activation of the caspase cascade and was abolished by treatment with a general caspase inhibitor. Mechanistic investigations demonstrated that induction of apoptosis by CYLD knockdown was caused by upregulation of receptor-interacting protein kinase 1 (RIPK1) that was associated with elevated K63-linked polyubiquitination of the protein, indicating that CYLD is critical for controlling RIPK1 expression in these cells. Of note, microRNA (miR) profiling showed that miR-99b-3p that was predicted to target the 3-untranslated region (3-UTR) of the CYLD mRNA was reduced in melanoma cell lines with high levels of CYLD compared with melanocyte lines. Further functional studies confirmed that the reduction in miR-99b-3p expression was responsible for the increased expression of CYLD in a highly cell line-specific manner. Taken together, these results reveal an unexpected role of CYLD in promoting survival of a subset of melanoma cells and uncover the heterogeneity of CYLD expression and its biological significance in melanoma.

Poly(acrylic acid) (PAA) hydrogels with a multi-bond network composed of sparse chemical cross-links and carboxyl-Fe3+coordination are prepared through a controllable permeation strategy utilizing ferric citrate (FeCA). The existing strategies that directly soak PAA hydrogels in Fe3+solutions usually induce an inhomogeneous network with densely cross-linked shells and uncertain water content of the hydrogels, which brings about ambiguity when investigating strengthening mechanisms because water content significantly affects the mechanical properties of hydrogels. Herein, the controllable permeation of Fe3+into PAA networks based on the competition between citric acid (CA)-Fe3+chelation and PAA-Fe3+coordination guarantees sustained release of Fe3+, facilitating homogeneous distribution of ionic cross-links and a certain water content. The obtained hydrogels exhibit excellent and balanced mechanical properties (high tensile strength of 3.28 to 6.95 MPa with large elongations at break of 1400 to 780% when water content decreases from 80 to 50 wt %). The real robust tensile strength of this hydrogel originates from the effective energy dissipation of the homogeneous PAA-Fe3+cross-links, and the high water content ensures a large elongation at break. Furthermore, the hydrogel also has pH-responsive and shape-memory properties.

The aim of this study was to evaluate the growth of rape (Brassica napusL.) seedlings under different light intensities to select appropriate conditions for cultivation in an indoor system. Seedlings were grown under different light intensities of red and blue light provided by light-emitting diodes (LEDs) and their self-adjustment ability and changes in leaf microstructure were evaluated. Light was supplied by red LEDs with peak wavelengths of 630 (R1) and 660 nm (R2) and by blue LEDs (B) with a peak wavelength of 445 nm (the light intensity ratio of R1:R2:B was 3:3:2), at intensities of 400 (R1R2B400), 300 (R1R2B300), and 200 μmol m−2s−1(R1R2B200). Natural solar light served as the control (C). Plant height, stem diameter, root length, leaf area, and dry weight of rape seedlings gradually increased with increasing light intensity. The seedlings in the R1R2B400 treatment grew more vigorously, while those in the R1R2B200 treatment were weaker. The photosynthetic pigment contents did not differ significantly between the R1R2B400 treatment and C, but were significantly lower in the R1R2B300 and R1R2B200 treatments. The highest intercellular CO2concentration, stomatal conductance, and transpiration rate were in the R1R2B300 treatment. The highest photosynthetic rate was in the R1R2B400 treatment, and was related to more compact leaves, thicker and tidier palisade and spongy tissues, and well-developed chloroplasts. In contrast, the seedlings in the R1R2B200 treatment had disordered mesophyll cells, round chloroplasts, and fractured and fuzzy grana lamellae, all of which inhibited plant growth. In conclusion, the seedlings in the R1R2B400 treatment had well-developed leaves, which favored photosynthesis. Compared with the light intensities below 300 μmol m−2s−1, the light intensity of 400 μmol m−2s−1provided by a combination of red and blue LEDs was beneficial for cultivating strong and healthy rape seedlings in an artificial system.

Molecular research is moving towards big data epoch. There are various large-scale popular databases abstracted from different biological processes. Integrating such valuable information with the statistical model may shed light on how human cells work from a system-level perspective. In this paper, we propose a novel penalised network-constrained regression model with a new L1/2solver for integrating gene regulatory networks into an analysis of gene-expression data, where the network is graph Laplacian regularised. Extensive simulation studies showed that our proposed approach outperforms L1regularisation and old L1/2regularisation regarding prediction accuracy and predictive stability. We also apply our method to three kinds of cancer data sets. Particularly, our method achieves comparable or higher predictive accuracy than the old solver L1/2and L1regularisation approaches, while fewer but informative genes and pathways are selected.

Large nonlinear rotor-bearing system is an important structure in rotating machinery, such as NC machine. Due to the mass imbalance of the system, vibrations induced by centrifugal forces inevitably exist in rotating machinery. So, nonlinear dynamic response of a complex rotor-bearing system was dealt with in this paper. The system considered was modeled using the finite element method and has 124 DOFs (degrees of freedom). A linear reduction method was used and a reduced-order dynamic model of the system with two DOFs had been obtained. Harmonic balance method was applied to the reduced-order dynamic model of the system and an approximate analytical expression of the solution for nonlinear dynamic response of the system at steady state was derived. The analytical solution obtained from the reduced-order dynamic model of the system was compared with the numerical one obtained from the direct integration of the equations of motion of the original system.

Poly(acrylic acid) nanocomposite physical hydrogels, with excellent mechanical properties and a high swelling capacity, were prepared by in situpolymerization.

Although RIPK1 (receptor [TNFRSF]-interacting protein kinase 1) is emerging as a critical determinant of cell fate in response to cellular stress resulting from activation of death receptors and DNA damage, its potential role in cell response to endoplasmic reticulum (ER) stress remains undefined. Here we report that RIPK1 functions as an important prosurvival mechanism in melanoma cells undergoing pharmacological ER stress induced by tunicamycin (TM) or thapsigargin (TG) through activation of autophagy. While treatment with TM or TG upregulated RIPK1 and triggered autophagy in melanoma cells, knockdown of RIPK1inhibited autophagy and rendered the cells sensitive to killing by TM or TG, recapitulating the effect of inhibition of autophagy. Consistently, overexpression of RIPK1 enhanced induction of autophagy and conferred resistance of melanoma cells to TM- or TG-induced cell death. Activation of MAPK8/JNK1 or MAPK9/JNK2, which phosphorylated BCL2L11/BIM leading to its dissociation from BECN1/Beclin 1, was involved in TM- or TG-induced, RIPK1-mediated activation of autophagy; whereas, activation of the transcription factor HSF1 (heat shock factor protein 1) downstream of the ERN1/IRE1-XBP1 axis of the unfolded protein response was responsible for the increase in RIPK1 in melanoma cells undergoing pharmacological ER stress. Collectively, these results identify upregulation of RIPK1 as an important resistance mechanism of melanoma cells to TM- or TG-induced ER stress by protecting against cell death through activation of autophagy, and suggest that targeting the autophagy-activating mechanism of RIPK1 may be a useful strategy to enhance sensitivity of melanoma cells to therapeutic agents that induce ER stress.

A software quality evaluation method for vehicle based on set pair theory was proposed. The evaluating index system of software quality evaluation for vehicle was constructed. The software quality evaluation models were constructed by using four-element connection number of set pair theory. Then the computer-implemented method was given, and was verified by an example. Finally, the practical application showed that the evaluation method was simple, effective and had good practicality.

This article reports the effect of MnCO3 addition on the grain refinement efficiency of AZ91 magnesium alloy. The results indicate that the addition of MnCO3 has excellent grain refining efficiency for AZ91 alloy, which is mainly attributed to the Al4C3 particles formed in the melt, besides Mn is indispensable to grain refinement in Al-bearing magnesium alloys. There is an optimal addition amount of 0.6% at 740 °C and the grain size is reduced from 245 to 91 μm. At the same time, the corrosion resistance performance of MnCO3-added AZ91is improved.

Control valve is the key element for a thermal power unit. As the core component of the valve assembly, the machining quality of valve bodys mating part is an important factor to restrict the performance of valve, so during the machining process, the demands for dimensional accuracy and surface quality of mating surface are quite high. Firstly, set the cutting tool, cutting parameters and other initial conditions according to enterprises actual requirements of body machining. The Deform 3D which is metal cutting finite element software was used to simulate the boring finishing process of mating surface of the valve body, can effectively analyze the changing rule of cutting force and cutting temperature with time. Then, the single factor analysis method was used to analyze the deformation of boring cutter due to cutting force, temperature and abrasion under the condition of different cutting parameters, which influence the quality and precision of valve bodys machining surface. The analysis results obtained in this paper will provide reference for the choice of cutting parameters in the process of actual valve body finish machining.

The torque shaft of shearer cutting part plays a dual-function of torque transmission and overload protection when the Shearer is working. Therefore it is necessary to study the reliability of the torque shaft. First, the parameterized torque shaft model was built on Inventor and simple parametric analysis of the torque shaft was done by its finite element analysis module. The unloading groove depth 5.079mm met the overload protection requirements. Then the model was imported into professional finite element analysis software Algor to verify the results. Linear statics analysis in Algor showed that when unloading groove depth valued 5.479mm the torque shaft would be broken once the shearer overload. The results of the analysis were reliable as no data was lost during the model interaction between Inventor and Algor.

The growth kinetics and morphology of intermetallic compound (IMC) between Sn-3Ag-0.5Cu -xFe (x= 0, 0.5wt.%, 1wt.%) composite solders and Cu substrate were investigated in the present work. The Sn-Ag-Cu-Fe/Cu solder joint were prepared by reflowing for various durations at 250℃. During soldering process, Fe particles quickly deposited in the vicinity of IMC, resulting in the formation of Fe-rich area. It was shown that Fe could effectively retard the growth of interfacial Cu6Sn5 and Cu3Sn layers during liquid-state reaction and reduce the size of Cu6Sn5 grains. Small cracks were observed in the Cu6Sn5 grains of Sn-Ag-Cu/Cu interface after reflowing for 30 min while they were not found in the other composite solders.

In this work, TiO2 nanoparticles (NPs) were prepared through a well-developed hydrothermal method. The dry products were characterized by digital camera, transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermogravimetric method (TGA). These results suggested that TiO2NPs were well-crystallized and oleic acid-capped (OA-capped; 33.42 wt.%). In order to investigate the flocculation and stability of TiO2NPs colloids, redispersed experiments were carried out by altering the preparative parameters (e.g., redispersion solvent, washing times). In addition, the compounding stability of TiO2NPs colloids with AuNPs colloids and MnO4- solution under processing conditions (e.g., aging with stirring and under UV irradiation) were also studied. In principle, systematic investigations of flocculation and stability of TiO2NPs will be useful for their potential applications including novel photocatalysts and biosensors.

Urea-formaldehyde resin was modified by a modifier with different synthetic processes labelled as UFM1, UFM2, and UFM3 respectively. As a comparison, normal UF resin with a F/U molar ratio of 1.1 labelled as UF0 was synthesized. The thermal behavior of modified urea-formaldehyde resins was studied by TG-DTA techniques, and the properties of plywood bonded with the UFM resins were investigated. The conclusions were as follows: (1) the modifier used in this study could significantly reduce the free formaldehyde content of urea-formaldehyde resin and the formaldehyde emission of plywood; (2) The exothermic peak temperatures of DTA curve were 129.37, 125.05, 120.98, and 116.11 °C for UF0, UFM1, UFM2, and UFM3 respectively. (3) The plywood manufactured with UFM2 and UFM3 resins have high bonding strength (1.28MPa and 1.59MPa) and low formaldehyde emission value (E1 grade).

The effect of melamine content in melamine modified urea formaldehyde (MUF) resin on durable properties of plywood was investigated using ammonium chloride (NH4Cl) with different melamine/urea (M/U) ratios. The plywood specimens were exposed to laboratory accelerated aging and/or cyclic soak-dry (SD). The experiment results indicated that the melamine contents in MUF resin showed an unobservable effect on the durable properties of MUF resin bonded plywood. The mechanical properties of plywood decreased more severely after accelerated aging test in acidic condition. However, the influence of different curing catalyst contents on mechanical properties and formaldehyde emission of UF resin can be minimized by adding melamine to the resin.

Jatropha curcas (Jc) was the most favored biomass plant for bio-diesel production. Jc cakes obtained after oil pressed, rich in protein content, were excellent materials for preparing formaldehyde-free wood adhesives, which could provide alternative to formaldehyde-based resins. Sodium hydroxide, used as denaturing agent, modified protein contained in Jc cakes to prepare wood adhesives. Jc adhesives prepared in different pH value and plywood bonded by them were prepared. The curing behavior of these adhesives was conducted by differential scanning calorimetry (DSC) measurement. The gel content and water absorption of the cured Jc adhesives were measured to evaluate their curing content and the water resistant of plywood bonded with these adhesives was also studied. The results showed that pH value influenced the bonding strength of adhesive significantly. The bonding strength of plywood made by modified Jc adhesive significantly increased comparing with that of unmodified one. The curing peak temperature decreased obviously after modified, which was beneficial to achieve complete curing reaction. Modified Jc adhesives provided a potential way to utilize by-product of energy plant, avoided formaldehyde pollution, and reduced dependence on fossil resources.

Presented herein is a finite element investigation into the damage mechanism of the adhesive interface of the rubber-steel bimaterial. The cohesive element layer is used at the interface to simulate the initial loading, initiation and propagation of the damage. From the simulation results, it is found that interface strength exert significant effects on the crack formation in the interface. Smaller interface strength could lead to crack initiation more easily.

For increasing the curing rate and decreasing the curing temperature, modified phenol-formaldehyde (PF) resins were synthesized under a complex catalyst. The bonding strength and formaldehyde emission of the plywood bonded by them were measured according to Chinese National Standards methods. The curing behavior was conducted by differential scanning calorimetry (DSC) measurement. The results indicate that PF resins catalyzed by the complex catalyst show more moderate pH values, lower curing temperature and shorter gel time comparing with control ones. Plywood bonded with modified PF resins shows good bonding strength and low formaldehyde emission even at low hot press temperature (110 °C), which is closed to the plywood bonded with normal control PF resin at high hot press temperature (130 °C).

Factor D is a serine protease essential for the activation of the alternative pathway of complement. The structures of native factor D and a complex formed with isatoic anhydride inhibitor were determined at resolution of 2.3 and 1.5 A˚, respectively, in an isomorphous monoclinic crystal form containing one molecule per asymmetric unit. The native structure was compared with structures determined previously in a triclinic cell containing two molecules with different active site conformations. The current structure shows greater similarity with molecule B in the triclinic cell, suggesting that this may be the dominant factor D conformation in solution. The major conformational differences with molecule A in the triclinic cell are located in four regions, three of which are close to the active site and include some of the residues shown to be critical for factor D catalytic activity. The conformational flexibility associated with these regions is proposed to provide a structural basis for the previously proposed substrate-induced reversible conformational changes in factor D. The high-resolution structure of the factor D/isatoic anhydride complex reveals the binding mode of the mechanism-based inhibitor. The higher specificity towards factor D over trypsin and thrombin is based on hydrophobic interactions between the inhibitor benzyl ring and the aliphatic side-chain of Arg218 that is salt bridged with Asp189 at the bottom of the primary specificity (S1) pocket.Comparison of factor D structural variants with other serine protease structures revealed the presence of a unique “self-inhibitory loop”. This loop (214–218) dictates the resting-state conformation of factor D by (1) preventing His57 from adopting active tautomer conformation, (2) preventing the P1 to P3 residues of the substrate from forming anti-parallel β-sheets with the non-specific substrate binding loop, and (3) blocking the accessibility of Asp189 to the positive1y charged P1 residue of the substrate. The conformational switch from resting-state to active-state can only be induced by the single macromolecular substrate, C3b-bound factor B. This self-inhibitory mechanism is highly correlated with the unique functional properties of factor D, which include high specificity toward factor B, low esterolytic activity toward synthetic substrates, and absence of regulation by zymogen and serpin-like or other natural inhibitors in blood.