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91.
Chih-Wei Tsao Pei-Shan Ke Hsin-Yi Yang Ting-Chia Chang Chin-Yu Liu 《International journal of molecular sciences》2022,23(17)
Increasing reports on the significance of dietary patterns in reproduction have arisen from both animal and human studies, suggesting an interactive association between nutrition and male fertility. The aim of this study was to investigate the effects of curcumin supplementation on low-carbohydrate-diet-induced metabolic dysfunction, testicular antioxidant capacity, apoptosis, inflammation and spermatogenesis in male mice. Male C57BL/6 mice were fed a normal diet (AIN-93M group, n = 12) and a low-carbohydrate diet for 12 weeks (LC group, fed with low-carbohydrate diet, n = 48), and mice randomly chosen from the LC group were later fed their original diet (LC group, n = 12). This diet was changed to AIN-93M feed (LC/AIN-93M group, n = 12), a ketogenic diet (LC/KD group, n = 12), or a ketogenic diet treated with curcumin supplementation for the final 6 weeks (LC/KDCu group, n = 12). A poor sperm morphology and mean testicular biopsy score (MTBS) were observed in the LC and LC/KD groups, but they were eliminated by the normal diet or ketogenic diet with curcumin. The LC group exhibited a lower testicular testosterone level and a lower 17β-HSD activity and protein expression. This also enhanced apoptosis protein expressions in testis tissue, including Bax/BCl2, cleaved caspase 3, PARP and NF-κB. Meanwhile, we found a statistically significant increase in lipid peroxidation and decreased superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase levels in the LC group. Our study indicated that a replacement of a normal diet or ketogenic diet supplemented with curcumin attenuated poor semen quality and reduced testosterone levels by the LC diet by reducing oxidative stress. 相似文献
92.
93.
Ko-Shao Chen Jui-Che Tsai Chih-Wei Chou Mu-Rong Yang Jen-Ming Yang 《Materials science & engineering. C, Materials for biological applications》2002,20(1-2):203-208
In this study, the thermosensitive gels were grafted onto plasma-activated polyethylene terephthalate (PET) film and polypropylene (PP) nonwoven fabric surface. The Ar* plasma pretreatment was carried out and subsequent photo-induced surface graft polymerization was employed to graft the N-isopropylacrylamide (NIPAAm). The effects of additives during the grafting were accessed. The additives used were ammonium peroxodisulfate (APS, initiator), N,N,N′,N′-tetra-methylethylene-diamine (TEMED, promoter) and N,N′-methylenebisacrylamide (NMBA, cross-linking agent). The results indicate that the additives of APS, TEMED and NMBA will be beneficial in promoting the grafting. The additives, including all three, will give the best result. These grafted gels exhibit a lower critical solution temperature (LCST) at about 32 °C, which shows that the temperature-responsive behavior of bulk P (NIPAAm) hydrogel was preserved. 相似文献
94.
95.
Cheng-Ying Ho Jenq-Gong Duh Chih-Wei Lin Chun-Jen Lin Yu-Hui Wu Huei-Cheng Hong Te-Hui Wang 《Journal of Materials Science》2013,48(6):2724-2732
Electroless Ni–P/electroless Pd/immersion Au (ENEPIG) with ultra-thin Ni–P deposit serve as a potential replacement of traditional ENEPIG surface finish because of its superior electrical performance in flip chip solder joints interconnection. However, the interfacial reaction and mechanical reliability of solder joints in ENEPIG with ultra-thin Ni–P layer is not yet well evaluated. In this study, we investigated the characteristic microstructure of interfacial intermetallic compounds and high-speed impact responses of Sn–3.0Ag–0.5Cu/ENEPIG attachments with 4.8, 0.3, and 0.05 μm Ni–P deposit. ENEPIG with Ni–P layer of 0.3 μm exhibited the eutectic structure dispreading in the solder alloys and layer-type P-rich IMCs at solder/metallization interface, while there was (Cu,Ni)6Sn5 precipitation in the solder but no P-rich IMCs layer formed in ENEPIG with 0.05 μm Ni–P layer. Slower interfacial reaction rate in ENEPIG with 0.3 μm Ni–P layer was attributed to the effect of electroless Ni–P diffusion barrier layer, which would further provide better impact resistivity than that of ENEPIG with 0.05 μm Ni–P deposit. Moreover, breach in P-rich IMCs and underneath (Cu,Ni)6Sn5 patch were observed in ENEPIG with 0.3 μm Ni–P layer. The growth mechanism was closely related to the Ni diffusion from surface finish and element redistribution. 相似文献
96.
Dhananjaya Patra Mohan Ramesh Duryodhan Sahu Harihara Padhy Chih-Wei Chu Kung-Hwa Wei Hong-Cheu Lin 《Polymer》2012,53(6):1219-1228
Stille polymerization was employed to synthesize a low-band-gap (LBG) conjugated main-chain polymer PBTH consisting of bithiazole, dithieno[3,2-b:2′,3′-d]pyrroles (DTP), and pendent melamine derivatives. Novel supramolecular polymer networks PBTH/C and PBTH/F were developed by mixing proper molar amounts of polymer PBTH (containing melamine pendants) to be hydrogen-bonded (H-bonded) with complementary uracil-based conjugated cross-linkers C and F (i.e., containing two symmetrical uracil moieties connected with carbazole and fluorene units through triple bonds). The formation of multiple H-bonds between polymer PBTH and cross-linkers C or F was confirmed by FT-IR measurements. In contrast to polymer PBTH, the supramolecular design with multiple H-bonds can enhance the photovoltaic properties of polymer solar cell (PSC) devices containing H-bonded polymer networks PBTH/C and PBTH/F by tuning their light harvesting capabilities, HOMO energy levels, and crystallinities. Initially, the power conversion efficiency (PCE) values of PSC devices containing supramolecular polymer networks PBTH/C and PBTH/F as electron donors and [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM) as an electron acceptor (polymer:PC70BM = 1:1 w/w) are found to be 0.97 and 0.68%, respectively, in contrast to 0.52% for polymer PBTH. The highest PCE value of 1.56% with a short-circuit current densities (Jsc) value of 7.16 mA/cm2, a open circuit voltages (Voc) value of 0.60 V, and a fill factor (FF) of 0.36 was further optimized in the PSC device containing a supramolecular polymer network PBTH/C as polymer:PC70BM = 1:2 w/w. These results indicate that supramolecular design is an effective route towards better photovoltaic properties of Voc, Jsc, and PCE values in polymer solar cells. 相似文献
97.
Shaking table tests on a saturated sand specimen in a laminar shear box were performed to measure the coupled shear strain-pore pressure response of sands subjected to horizontal shaking. Three methods of shear strain evaluation techniques, which use soil motions recorded by embedded sensors within the soil specimen and external sensors on frame, were utilized to evaluate the shear strain-time histories in one-dimensional shaking cases. Coupled shear strain-pore pressure responses throughout the liquefaction process are presented based on evaluated shear strains and measured pore pressures at corresponding depths. More insights of the interactions between the induced shear strain and generated excess pore pressure are also given, including the temporal variations of induced shear strain prior and after the initial liquefaction, development of liquefied zone, and duration of liquefaction state. These spatial and temporal variations of coupled responses reveal that the induced shear strain amplitude is not only an important property in triggering soil liquefaction but also a better index in defining the time of initial liquefaction. Identifications of these coupled features will be beneficial for verifying and interpreting testing data in physical modelling for liquefaction studies. 相似文献
98.
99.
Counter electrode coated with chemically polymerized poly(3,4-ethylenedioxythiophene) (PEDOT) in a dye-sensitized solar cell (DSSC) was studied. The surface morphology and the nature of I−/I3− redox reaction based on PEDOT film were investigated using Atomic Force Microscopy and Cyclic Voltammetry, respectively. The performance of the DSSCs containing the PEDOT coated electrode was compared with sputtered-Pt electrode. We found that the root mean square roughness decreases and conductivity increases as the molar ratio of imidazole (Im)/EDOT in the PEDOT film increases. The DSSC containing the PEDOT coated on fluorine doped tin oxide glass with Im/EDOT molar ratio of 2.0, showed a conversion efficiency of 7.44% compared to that with sputtered-Pt electrode (7.77%). The high photocurrents were attributed to the large effective surface area of the electrode material resulting in good catalytic properties for I3− reduction. Therefore, the incorporation of a multi-walled carbon nanotube (MWCNT) in the PEDOT film, coated on various substrates was also investigated. The DSSC containing the PEDOT films with 0.6 wt.% of MWCNT on stainless steel as counter electrode had the best cell performance of 8.08% with short-circuit current density, open-circuit voltage and fill factor of 17.00 mA cm−2, 720 mV and 0.66, respectively. 相似文献
100.
Feng-Ming Lee Chia-Lung Tsai Chih-Wei Hu Fu-Yi Cheng Meng-Chyi Wu Chia-Chien Lin 《Electron Devices, IEEE Transactions on》2008,55(2):540-546
In this paper, we report the fabrication of high-reliability and high-speed 1.3 mum complex-coupled distributed feedback (CC-DFB) buried heterostructure (BH) laser diodes (LDs) with Fe-doped InGaAsP/InP hybrid grating layers. High optical coupling coefficient and eminent current confining ability are accomplished by combining the Fe-doped InGaAsP/InP current-blocking-grating (CBG) layers to provide both the distributed-feedback index-and gain-coupling coefficients. Besides, the narrow-stripe BH LDs are implemented by burying the active region with a Fe-doped InP current-blocking layer during the epitaxial regrowth. The fabricated CBG CC-DFB BH LDs at 20degC shows a low threshold current of 5.3 mA, a maximum light output power of 36 mW at 100 mA, a high slope efficiency of 0.41 mW/mA, and a side-mode suppression ratio (SMSR) of 42 dB at twice the threshold. In addition, these LDs exhibit a maximum operation temperature of 125degC, an extremely low threshold current of 15.8 mA at 90degC, a small variation in slope efficient of only -1 dB in the temperature range from 20degC to 80degC, and a characteristic temperature of 77 K and 56 K between 20 degC and 60degC, and 70degC and 120degC, respectively. Furthermore, these 1.3 mum CBG CC-DFB BH LDs exhibit a high-speed characteristic up to 11.8 GHz at room temperature and an estimated median lifetime of more than 1.1 times 105 h or 12.5 years at 5 mW and 85degC. 相似文献