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High-temperature proton exchange membranes (HTPEMs) based on arginine-modified phosphoric acid-doped polybenzimidazole (Arginine-PBI-PA) and poly(tetrafluoroethylene) phosphoric acid-doped polybenzimidazole (PTFE-Arginine-PBI-PA) were fabricated and characterized for fuel cell applications. Arginine as filler was used to prepare HTPEMs for the first time, and the Arginine-PBI-PA membrane exhibited an excellent proton conducting ability with 24.1 mS cm−1 at 160 °C while maintaining mechanical strength. Furthermore, Arginine-PBI-PA composite membrane was also appropriate for membrane electrode assemblies (MEAs), and it exhibited better fuel cell performances (0.68 V@400 mA cm−2) compared with the PBI-PA membranes prepared. Molecular dynamics (MD) simulation revealed that the better electrochemical properties of Arginine-PBI-PA membranes over PBI-PA membranes were ascribed to the strong interactions between the basic sites and carboxyl groups of arginine and PA molecules, respectively. In addition, the higher proton conductivity for Arginine-PBI-PA membranes was attributed to the formation of a tighter H-bonding network and the interaction between arginine non-protonated oxygen (O) and PA protons (HPA). Experimental investigation and molecular dynamics simulation of novel arginine/PBI composite membranes for high temperature PEM fuel cells [ABSTRACT FROM AUTHOR]

Four novel donor-π-bridge-acceptor(D-π-A) main chain polymeric metal complexes (P1, P2, P3 and P4) as dye sensitizers for dye-sensitized solar cells (DSSCs) based on Zn(II) or Cd(II) complexes with fluorene and 8-hydroxyquinoline ligand have been synthesized by the Heck coupling and characterized by FT-IR, Elemental analysis and GPC. The optical properties, thermal properties, electrochemical properties and photovoltaic properties of these polymeric metal complexes have been investigated and studied by TGA, DSC, C-V curves and I-V curves. DSSCs based on P1 and P3 show good photovoltaic performances and the corresponding power conversion efficiency (PCE) are up to 1.99 % (J = 4.59 mA cm, V = 0.68 V, FF = 0.636) and 2.05 % (J = 5.25 mA cm, V = 0.60 eV, FF = 0.65) under simulated AM 1.5 G solar irradiation (100 mW cm). Besides, they showed good stabilities with thermal decomposition Temperatures are 421, 441, 413, 385 °C, respectively, which are suitable for DSSCs. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The expression and regulation of metalloproteinases-2, -9 (MMP-2, -9) and their tissue inhibitors TIMP-1,-2, -3 mRNA were studied in this experiment. In the PMSG-hCG primed pseudopregnant rat, MMP-2, -9 mRNA levels were the highest at Day 1, decreased from Day 4, and reached the minimal level at Day 8, then increased at Day 14; no significant changes were observed in TIMP-2 mRNA expression from Day 1 to Day 14; TIMP-3 mRNA expression was the lowest at Day 1, increased from Day 4, reached the maximal level at Day 8, and persisted to Day 14. TNF-α could significantly increase the expression of MMP-2, -9 and TIMP-1 mRNA in thein vitro perfused pseudopregnant CL, and decrease the expression of TIMP-3 mRNA, but had no effect on TIMP-2 mRNA expression. The results indicate that MMP-2, -9 and TIMP-1, -2, -3 might be involved in the regulation of CL function and maintenance of CL structure via their coordinated gene expression. TNF-a could inhibit luteal regression via increasing MMP-2, -9 and TIMP-1 mRNA in thein vitro perfused pseudopregnant ovary. [ABSTRACT FROM AUTHOR]

Discusses the expression and regulation of metalloproteinases-2, -9 (MMP-2, -9) and their tissue inhibitors TIMP-1, -2, -3 mRNA. Observation of MMP-2, -9 mRNA levels in the PMSGhCG primed pseudopregnant rat; Indication there were no significant changes in TIMP-2 mRNA expression from Day 1 to Day 14; TIMP-3 mRNA expression was the lowest at Day 1; Suggestion that TNF-α can increase the expression of MMP-2, -9 and TIMP-1 mRNA in the in vitro perfused pseudopregnant CL, decrease the expression of TIMP-3 mRNA, and have no effect on TIMP-2 mRNA expression; Conclusion that MMP-2, -9 and TIMP-1, -2, -3 could be involved in the regulation of CL function and the maintenance of CL structure through their coordinated gene expression; Assertion that TNF-α could inhibit luteal regression in the in vitro perfused pseudopregnant ovary.

The mechanical and acoustic properties of Ti2NiZ (Z = Al, Ga and In) Heusler alloys under different pressures were studied based on the second- and third-order elastic constants obtained by the ab initio calculations combined with homogeneous deformation theory. The results showed that the mechanical stability is reduced while the ductility is improved with increasing pressure for all three alloys. As the pressure increases, the acoustic velocities of these alloys increase except for the transverse acoustic velocities in ⟨110⟩ direction of Ti2NiGa and Ti2NiIn. The Debye temperature and minimum thermal conductivity were also predicted in terms of the obtained acoustic velocities, which increase with increasing pressure for all three alloys. The calculated lattice constants, band gaps and second-order elastic constants were in agreement with the available theoretical values. [ABSTRACT FROM AUTHOR]

HTO has proven to be a cost-effective surgical procedure in the treatment of KOA, but few investigations have studied radiological changes and clinical effectiveness of OWHTO in geriatric patients. 76 patients were recruited in this retrospective study. According to the age, patients were divided into two groups (≤ 60, Group "Young"; > 60, Group "Geriatric"). Demographic data, radiological imaging and postoperative complications were analyzed. Kellgren–Lawrence grade (K–L), weight-bearing line ratio (WBLR); posterior tibial slope angle (PTS); American knee score (AKS); Western Ontario and McMaster Universities Arthritis Index (WOMAC) and visual analog scale (VAS) were introduced to estimate the clinical outcome of OWHTO. There were 18 male and 58 female patients in the present study with a mean age of 58.5 ± 9.2 years (ranges from 40 to 82 years); the average age was 51.4 ± 4.1 years and 67.3 ± 4.9 years for group Y and G respectively, 44.7% and 31.5% patients were older than 60 and 65 years. BMI for the 76 patients was 26.6 ± 3.2 kg/m2, and geriatric patients were more likely accompanied by one or more comorbidities (70.6 vs. 45.2%). There were 34 and 42 patients in group Geriatric and group Young respectively, and no significant difference of MPTA, WBLR, PTS and WOMAC, VAS, AKS and ROM between the two group (P > 0.05) were found. After more than a two-year follow-up period, postoperative WBLR, AKS, WOMAC and VAS were much more desired than preoperative, and no significant difference of these variables between the young and geriatric group (P > 0.05), however, elderly patients were more likely to suffer from a longer bone union time. OWHTO can avoid geriatric patients from undergoing secondary knee surgery in the short term, however the survival rate of OWHTO in geriatric patients should be ultimately clarified by different studies. [ABSTRACT FROM AUTHOR]

High myopia (HM), which is characterized by oxidative stress, is one of the leading causes of visual impairment and blindness across the world. Family and population genetic studies have uncovered nuclear-genome variants in proteins functioned in the mitochondria. However, whether mitochondrial DNA mutations are involved in HM remains unexplored. Here, we performed the first large-scale whole-mitochondrial genome study in 9613 HM cases and 9606 control subjects of Han Chinese ancestry for identifying HM-associated mitochondrial variants. The single-variant association analysis identified nine novel genetic variants associated with HM reaching the entire mitochondrial wide significance level, including rs370378529 in ND2 with an odds ratio (OR) of 5.25. Interestingly, eight out of nine variants were predominantly located in related sub-haplogroups, i.e. m.5261G > A in B4b1c, m.12280A > G in G2a4, m.7912G > A in D4a3b, m.94G > A in D4e1, m.14857 T > C in D4e3, m.14280A > G in D5a2, m.16272A > G in G2a4, m.8718A > G in M71 and F1a3, indicating that the sub-haplogroup background can increase the susceptible risk for high myopia. The polygenic risk score analysis of the target and validation cohorts indicated a high accuracy for predicting HM with mtDNA variants (AUC = 0.641). Cumulatively, our findings highlight the critical roles of mitochondrial variants in untangling the genetic etiology of HM. [ABSTRACT FROM AUTHOR]

LaAlO:Mn and LaAlO:Mn, Na deep red-emitting phosphors are synthesized by a solid-state reaction method in air. Their crystal structures, lifetimes, and luminescence properties are investigated, respectively. PLE spectrum monitored at 730 nm contains three PLE bands peaking at ~276, 325, and 500 nm within the range 200-550 nm, and PL spectrum with excitation 325 nm exhibits two PL band peaks located at ~703 and 730 nm owing to anti-stokes vibronic sidebands associated with the excited state E of Mn ion and the E → A transition of Mn ion, respectively. The optimal Mn doping concentration is ~0.8 mol%. Lifetime of LaAlO:0.8 %Mn phosphor is ~0.92 ms. Na ion as charge compensator can improve obviously the luminescence properties of LaAlO:Mn phosphor due to the charge compensation. The luminous mechanism of Mn ion is explained by using Tanabe-Sugano diagram of Mn ion in octahedral crystal field. The contents of this paper will be helpful to develop novel Mn-doped materials and improve their luminescence properties. [ABSTRACT FROM AUTHOR]

A series of CaNbO: xSm (0 ≤ x ≤ 10 mol%) and CaNbO : Sm, Na/B phosphors were synthesized by the solid-state reaction method in air. Their crystal structures and luminescence properties were investigated and analysed, respectively. Host CaNbO emitted blue light with excitation 270 nm. CaNbO: xSm phosphors showed a systematically varied hue from blue to white by changing Sm ion concentration from 0 to 10 mol% with excitation of 270 nm and their chromaticity coordinates were the regions from (0.1665, 0.1767) to (0.2484, 0.2260). Luminescence properties of CaNbO : Sm phosphor were tuned and improved significantly by codoping B or Na ions. Energy transfer between Nb $_{\mathbf {2}}\textit {O}_{\mathbf {6}}^{\boldsymbol {2-}}$ group and Sm ion was observed and analysed via luminescence properties. The luminous mechanism was explained by energy level scheme and energy transfer process in CaNbO : Sm phosphor. The strong excitation band peaking at ∼407 nm indicated that the CaNbO : Sm, Na/B phosphor has a potential application in white light-emitting diodes based on near-UV LED chip. [ABSTRACT FROM AUTHOR]

Cracking of a cylindrical shell section from an absorption tower occurred during the hydraulic pressure testing. In order to find out the cause of failure, the cracked cylindrical shell section was inspected and destructively analyzed. Optical microscopy was performed to evaluate the basic microstructure of the material used to fabricate the cylinder and the effect of welding on the microstructure. The fracture surface was examined in a scanning electron microscope, and the effects of the heat treatment temperature on the structure and properties of 410S/16MnR explosively clad plate were investigated. Detailed metallographic studies indicated that bainite existed in the base layer of the explosively welded material. The weld-induced residual stress in the crack origin was investigated by a three-dimensional (3D) finite element model. The numerical result was consistent with the fracture analysis supporting the conclusion that cracking was caused by the poor mechanical properties of the explosively clad plate and that the poor properties were induced by improper heat treatment after explosive welding. The welding residual stresses also contributed to the failure process. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the expression of gelatinases and tissue inhibitors of metalloproteinases (TIMP) in the rhesus monkey corpus luteum (CL) in luteal and pregnancy stages. Role of matrix metalloproteinases and TIMP in the development of CL; Methodology; Results and discussion.