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The microstructure evolution and tensile properties of the Fe-10Mn-10Al-0.7C low-density steel annealed at the temperature range from 700 °C to 1200 °C for 1 h were investigated in the present study. The phases in the annealed specimens mainly included ferrite (a), austenite (β) and κ-carbide (κ). The dissolution temperature for κ-carbide is between 850 °C and 900 °C. At the annealing temperature of 700 °C, all the β phase transformed to a phase and κ-carbide by eutectoid reaction. As the annealing temperature rose from 700 °C to 900 °C, a phase and κ-carbide fraction decreased and β phase fraction increased, and ultimate elongation increased, while ultimate strength and yield strength had a decreasing trend. The β phase fraction in the specimen dominated the ultimate elongation, and the κ-carbide strengthened the specimen and weakened ductility. As the annealing temperature rose from 900 °C to 1200 °C, the phase fraction change was small but the grain size increased greatly. The rapid growth of the grains was the main reason why ultimate tensile strength and ultimate elongation decreased with the increase of annealing temperature over 900 °C. The steel designed here possessed a density of 6.80 g/cm3, which is about 13% lower than pure iron. [ABSTRACT FROM AUTHOR]

Objectives: Chronic pelvic pain syndrome is a common and serious health problem affecting the quality of life of men. We evaluated the prevalence of premature ejaculation (PE) in Chinese men with chronic pelvic pain syndrome and studied its correlation to chronic prostatitis. Methods: A total of 15 000 men (aged 15-60 years) were randomly recruited to take part in a survey to provide questionnaire-elicited information for sociodemographics, sexual function, National Institutes of Health-Chronic Prostatitis Symptom Index, and International Index of Erectile Function 5-item questionnaire. The eligible subjects of the present investigation were married with sexual activity. Results: Responses were collected from 12 743 men (84.95%). Of these men, 1071 (8.4%) reported having prostatitis-like symptoms. The incidence of chronic prostatitis was 4.5% (n = 571) for the entire group. Of the 7372 eligible men, the incidence of prostatitis-like symptoms, chronic prostatitis, and PE was 10.5% (n = 771), 5.0% (n = 370), and 15.3% (n = 1127), respectively. The group with PE had worse National Institutes of Health-Chronic Prostatitis Symptom Index scores (P < .05) and lower International Index of Erectile Function 5-item questionnaire scores (P < .05) than the patients without PE. Also, the percentage of prostatitis-like symptoms in the PE group was greater than that in the non-PE group (P < .05). The prevalence of PE was 64.1% and 36.9% in the prostatitis-like symptom and chronic prostatitis group, respectively, of the 7372 eligible men. Conclusions: The results of our study showed a high prevalence of PE in patients with chronic prostatitis. An examination of the prostate, physically and microbiologically, should be considered during the assessment of patients with PE. [ABSTRACT FROM AUTHOR]

Abstract: Two indica rice genotypes, viz. Milyang 46 and Zhenshan 97B differing in Cd accumulation and tolerance were used as materials in a hydroponic system consisting of four Cd levels (0, 0.1, 1.0 and 5.0 µmol/L) and three N levels (23.2, 116.0 and 232.0 mg/L) to study the effects of nitrogen status and nitrogen uptake capacity on Cd accumulation and tolerance in rice plants. N-efficient rice genotype, Zhenshan 97B, accumulated less Cd and showed higher Cd tolerance than N-inefficient rice genotype, Milyang 46. There was consistency between nitrogen uptake capacity and Cd tolerance in rice plants. Increase of N level in solution slightly increased Cd concentration in shoots but significantly increased in roots of both genotypes. Compared with the control at low N level, Cd tolerance in both rice genotypes could be significantly enhanced under normal N level, but no significant difference was observed between the Cd tolerances under normal N (116.0 mg/L) and high N (232.0 mg/L) conditions. The result proved that genotypic differences in Cd accumulation and toxicity could be, at least in part, attributed to N uptake capacity in rice plants. [Copyright &y& Elsevier]

• Multiple-ring-stiffened tube-gusset joints are investigated for their static strength. • Experimental studies of 13 specimens are conducted with numerical verification. • Influencing factor study by FE analysis helps reveal vital mechanical mechanisms. • Strength equations for multiple-ring-stiffened tube-gusset joints are proposed. Multiple-ring-stiffened (MRS) tube-gusset (TG) X-Joints have been widely adopted in steel tubular transmission towers for their excellent structural performances. However, no specific design guidance is available yet to determine the ultimate strengths of the joints. Therefore, experimental and numerical investigations are carried out to address this issue. Firstly, a total of thirteen specimens including unstiffened, triple-, and quinary-ring-stiffened joints are tested under static brace loads. Then, finite element models are established, and they are verified against the experimental data. Afterward, the numerical models are used for influencing factor analysis on the geometric configurations. Among the considered joint geometrics, the height of the ring has the most prominent influence on the joint strength, while the influence of the spacing of the rings is negligible. The joint with 160-mm-high ring stiffeners has a strength enhancement of 1600% in comparison with the unstiffened one. It is also concluded that the ultimate strength of the MRS TG X-Joint could be regarded as the strength of the unstiffened joint plus that of the rings, of which the latter accounts for 85% − 95%. This major contribution from the rings means that the failure mechanism of the joint is closely related to them, and that is the formation of plastic hinges at vortexes from bending action. According to this, an analytical model is proposed for the strength of the ring, and thus the formula. Furthermore, the equation for the strength of MRS TG X-Joint is given as the superposition of the formulae for the rings and the unstiffened joint. The accuracy of the equations is confirmed by the results of 455 numerical cases. This study therefore supplements the method to calculate the ultimate strength of MRS TG X-Joint. [ABSTRACT FROM AUTHOR]

Magnetic fields markedly affect the growth and development of many species of organisms potentially due to cryptochrome and endogenous presence of magnetic materials. Sensitivity to magnetic fields can also be involved in geomagnetic orientation by some long-distance migratory insects. In this study, near-zero magnetic fields (NZMF) in relation to normal geomagnetic fields (GMF) were setup using the Hypomagnetic Field Space System (HMFs) to investigate the effects of magnetic fields on the growth, development and reproduction of two species of migratory planthopper, the small brown planthopper (abbr. SBPH), Laodelphax striatellus, and the brown planthopper (abbr. BPH), Nilaparvata lugens. Exposure of both L. striatellus and N. lugens to NZMF delayed egg and nymphal developmental durations and decreased adult weight and female fecundity. The 1st-5th instars of SBPH and BPH showed different responses to NZMF. The 4th instar was significantly affected by NZMF, especially for BPH males, in which NZMF exposure reduced the difference in development duration between females and males. Compared with GMF, the vitellogenin transcript levels of newly molted female adults and the number of eggs per female were significantly reduced in both planthopper species, indicating a negative effect on fertility under NZMF. Our findings provided experimental evidence that NZMF negatively affected the growth and development of SBPH and BPH, with particularly strong effects on reproduction. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, an autonomous takeoff and landing control strategy is designed and implemented for a prototype coaxial unmanned helicopter with ducted fan configuration. The control strategy is designed such that longitudinal and lateral controls use ground forces, attitude and drifting feedbacks. Vertical control employs takeoff and landing decision and vertical velocity control is based on altitude tracking. Ground forces feedback is used to balance longitudinal forces and moments during liftoff effectively cancelling all ground forces. Attitude and drifting feedbacks are used to balance the longitudinal and lateral movements of the helicopter during takeoff and landing. The flight control strategy is successfully verified during flight tests. [ABSTRACT FROM AUTHOR]

A complete mapping of 14 nm FinFETs performance over 200 mm wafers was performed and the pattern dependency of SiGe selective growth was calculated using an empirical kinetic molecule model for the reactant precursors. The transistor structures were analyzed by conventional characterization tools and their performance was simulated by considering the process related variations. The applied model presents for the first time a powerful tool for transistor community to predict the SiGe profile and strain modulating over a processed wafer, independent of wafer size. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor (TNF)-stimulated gene-6 (TSG-6) binds to hyaluronan and can reorganize/stabilize its structure, also enhancing the binding of this glycosaminoglycan to its cell surface receptor, CD44. TSG-6 is rapidly up-regulated in response to inflammatory cytokines protecting tissues from the damaging effects of inflammation. Despite TSG-6 treatment having been shown to improve outcomes in an experimental model of traumatic brain injury, TSG-6 expression has not been extensively studied in the central nervous system (CNS). We hereby analyzed the expression profile of TSG-6 in the developing CNS and following injury. We show that TSG-6 is expressed in the rat CNS by GFAP+ and CD44+ astrocytes, solely in the mature brain and spinal cord, and is not present during the development of the CNS. TSG-6-/- mice present a reduced number of GFAP+ astrocytes when compared with the littermate TSG-6+/- mice. TSG-6 expression is drastically up-regulated after injury, and the TSG-6 protein is present within the glial scar, potentially coordinating and stabilizing the formation of this hyaluronan-rich matrix. This study shows that TSG-6 is expressed in the CNS, suggesting a role for TSG-6 in astrocyte activation and tissue repair. We hypothesize that within this context TSG-6 could participate in the formation of the glial scar and confer anti-inflammatory properties. Further studies are required to elucidate the therapeutic potential of targeting TSG-6 after CNS injury to promote its protective effects while reducing the inhibitory properties of the glial scar in axon regeneration. [ABSTRACT FROM AUTHOR]

Electrostatic potential distribution of Al2O3/Ge structure is investigated vs. Al2O3 thickness by X-ray photoelectron spectroscopy (XPS). The electrostatic potential distribution is found to be Al2O3 thickness dependent. This interesting phenomenon is attributed to the appearance of gap states on Al2O3 surface (GSAl2O3) and its higher charge neutrality level (CNL) compared with the CNL of gap states at Al2O3/Ge interface (GSAl2O3/Ge), leading to electron transfer from GSAl2O3 to GSAl2O3/Ge. In the case of thicker Al2O3, fewer electrons transfer from GSAl2O3 to GSAl2O3/Ge, resulting in a larger potential drop across Al2O3 and XPS results. Graphical abstractImage 1Highlights· The electrostatic potential distribution of Al2O3/Ge structure is found to be Al2O3 thickness dependent. · This interesting phenomenon is attributed to the appearance of gap states on Al2O3 surface. · Our work confirm the feasibility of gap state model in understanding the band lineup at oxide/semiconductor structure. [ABSTRACT FROM AUTHOR]

Tissue-engineered blood vessels (TEBVs) are promising in the replacement of diseased vascular tissues. However, it remains a great challenge to obtain a sufficient number of functional smooth muscle cells (SMCs) in a clinical setting to construct patient-specific TEBVs. In addition, it is critical to develop a scaffold to accommodate these cells and retain their functional phenotype for the regeneration of TEBVs. In this study, human induced pluripotent stem cells (iPSCs) were established from primary human aortic fibroblasts, and characterized with the pluripotency markers expression and cells' capabilities to differentiate into all three germ layer cells. A highly efficient method was then developed to induce these human iPSCs into proliferative SMCs. After multiple times of expansion, the expanded SMCs retained the potential to be induced into the functional contractile phenotype of mature SMCs, which was characterized by the contractile response to carbachol treatment, up-regulation of specific collagen genes under transforming growth factor β1 treatment, and up-regulation of specific matrix metalloproteinase genes under cytokine stimulation. We also developed an advanced macroporous and nanofibrous (NF) poly(l-lactic acid) (PLLA) scaffold with suitable pore size and interpore connectivity to seed these human iPSC-derived SMCs and maintain their differentiated phenotype. Subcutaneous implantation of the SMC-scaffold construct in nude mice demonstrated vascular tissue formation, with robust collagenous matrix deposition inside the scaffold and the maintenance of differentiated SMC phenotype. Taken together, this study established an exciting approach towards the construction of patient-specific TEBVs. We established patient-specific human iPSCs, derived proliferative SMCs for expansion, turned on their mature contractile SMC phenotype, and developed an advanced scaffold for these cells to regenerate vascular tissue in vivo. [ABSTRACT FROM AUTHOR]

The very largeGprotein-coupled receptor 1 (VLGR1) is a core component in inner ear hair cell development. Mutations in the vlgr1 gene cause Usher syndrome, the symptoms of which include congenital hearing loss and progressive retinitis pigmentosa. However, the mechanism of VLGR1-regulated intracellular signaling and its role in Usher syndrome remain elusive. Here, we show that VLGR1 is processed into two fragments after autocleavage at the G protein-coupled receptor proteolytic site. The cleaved VLGR1 β-subunit constitutively inhibited adenylate cyclase (AC) activity through Gαi coupling. Co-expression of the Gαiq chimera with the VLGR1 β-subunit changed its activity to the phospholipase C/nuclear factor of activated T cells signaling pathway, which demonstrates the Gαi protein coupling specificity of this subunit. An R6002A mutation in intracellular loop 2 of VLGR1 abolished Gαi coupling, but the pathogenic VLGR1 Y6236fsx1 mutant showed increased AC inhibition. Furthermore, overexpression of another Usher syndrome protein, PDZD7, decreased the AC inhibition of the VLGR1 β-subunit but showed no effect on the VLGR1 Y6236fsx1 mutant. Taken together, we identified an independentG αi signaling pathway of the VLGR1β-subunit and its regulatory mechanisms that may have a role in the development of Usher syndrome. [ABSTRACT FROM AUTHOR]

Although oligonucleotide chips, cDNA microarrays, differential display reverse transcription-PCR, and other approaches have been used to screen implantation-related molecules, the mechanism by which embryo implantation occurs is still unknown. The aim of this study was to profile the differential gene expression between interimplantation site and implantation site in mouse uterus on day 5 of pregnancy by serial analysis of gene expression (SAGE). In our two SAGE libraries of 11-bp tags, the total numbers of tags sequenced were 48,121 for the interimplantation site and 50,227 for the implantation site. There were 1,039 tags specifically expressed at interimplantation site, and 1,252 tags specifically expressed at the implantation site. Based on the p value, there were 195 tags significantly up-regulated at the interimplantation site and 261 tags significantly up-regulated at the implantation site, of which 100 genes were single matched at the interimplantation site and 127 genes were single matched at the implantation site, respectively. By reverse transcription-PCR, the tag ratio between the implantation site and interimplantation site was verified on 14 significantly changed genes. Using in situ hybridization, 1810014L12Rik, Psmb5, Cd63, Npm1, Fads3, and Tagln2 were shown to be highly expressed at the implantation site compared with the interimplantation site. Compared with the interimplantation site, Ddx39 was strongly expressed in the subluminal stromal cells at the implantation site on day 5 of pregnancy. Ddx39 expression at the implantation site was specifically induced by active blastocysts. Additionally, Ddx39 expression was significantly up-regulated by estrogen in the ovariectomized mice. In our SAGE data, many implantation-related genes were identified in mouse uterus. Our data could be a valuable source for future study on embryo implantation. [ABSTRACT FROM AUTHOR]

Neurodegenerative disorders such as Huntington's disease (HD) are fundamentally caused by accumulation of misfolded aggregate-prone proteins. Previous investigations have shown that these toxic protein aggregates could be degraded through autophagy induced by small molecules as well as by nanomaterials. However, whether engineered nanomaterials have the capacity to degrade these protein aggregates via the ubiquitin-proteasome system (UPS), the other major pathway for intracellular protein turnover, was unknown. Herein, we have synthesized biocompatible MnFe 2 O 4 nanoparticles (NPs) and demonstrated their unique effect in accelerating the clearance of mutant huntingtin (Htt) protein exhibiting 74 glutamine repeats [Htt(Q74)]. UPS, rather than autophagy, was responsible for the efficient Htt(Q74) degradation facilitated by MnFe 2 O 4 NPs. Meanwhile, we demonstrated that MnFe 2 O 4 NPs enhanced K48-linked ubiquitination of GFP-Htt(Q74). Moreover, ubiqinlin-1, but not p62/SQSTM1, served as the ubiquitin receptor that mediated the enhanced degradation of Htt(Q74) by MnFe 2 O 4 NPs. Our findings may have implications for developing novel nanomedicine for the therapy of HD and other polyglutamine expansion diseases. [ABSTRACT FROM AUTHOR]