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101.
With the development of new technology and use of lightweight material such as composite laminates, new methods must be developed for in situ structural health monitoring of these materials. This paper introduces an approach for the detection of delamination present in GLARE aluminium specimens. The approach is based on the change in group velocity of Lamb waves with frequency–thickness product as the determinant parameter for the detection of delamination. Two methods are applied: a surface contact method, which utilises a wedge probe tuned to excite a single Lamb mode, and the embedded PZT method, which involves incorporating lead zirconate titanate (PZT) elements in the glass fibre reinforced resin matrix during the manufacture of the GLARE aluminium specimens. It was found that both methods enabled the detection of delaminations in the GLARE aluminium specimens, within certain limits, which are stated. 相似文献
102.
A bibliometric analysis was performed to assess the quantitative trend of Patent Ductus Arteriosus (PDA) treatment research,
including intravenous injection of indomethacin and surgery. The documents studied were retrieved from the Science Citation Index (SCI) for the period from 1991 to 2002. The publication pattern concerning authorship, collaboration, original countries,
citation frequency, document type, language of publication, distribution of journals, page count and the most frequently cited
papers were performed. The results indicated that either treatment was not the recent emphasis of PDA research. The publishing
countries of both treatments have also denoted that these researches were mostly done in Europe and North America. Both surgery
and drug treatments had few international collaboration papers. English was the dominant language, and collaboration of two
to six authors was the most popular level of co-authorship.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
103.
In plastic injection moulding process, cooling channel design is an essential factor that affects the quality of the moulded parts and the productivity of the process. Non-uniform cooling or long cooling cycle time would result if a poorly designed cooling channel is adopted. Due to limitations of traditional machining processes, the cooling channel is usually formed from straight-line drilled holes and only simple shapes are allowed, regardless of the shape complexity of the part being moulded. With the advent of rapid tooling technology, cooling channels in complex shapes can now be possible. However, there are not many design methodologies for supporting this type of cooling channel. In this paper, a methodology called visibility-based cooling channel generation is proposed for automatic preliminary cooling channel design for rapid tooling. The cooling process between a mould surface and a cooling channel is considered analogous to whether they can be visible from each other. Without loss of generality, the mould surface is approximated by a polyhedral terrain and is normally offset. A number of point light sources together that can illuminate the whole polyhedral terrain are assigned to suitable terrain offset vertices. A cooling channel is then generated by connecting all the assigned light sources. When comparing the conventional verification and redesign methods by melt flow analysis, computer-aided design and, a better design of cooling channel for its mould surface results in a short time independent of the experience of mould engineer. 相似文献
104.
Soemmerring’s Rings Developed around IOLs,in Human Donor Eyes,Can Present Internal Transparent Areas
Justin Christopher DAntin Francesc Tresserra Rafael I. Barraquer Ralph Michael 《International journal of molecular sciences》2022,23(21)
Soemmerring’s rings consist of a ring of lens epithelial derived cells that grow along the periphery of an aphakic lens capsule, or around an intraocular lens. These rings when visualized frontally, appear opaque, however, in some cases the cells that compose these rings are organized in the same fashion as those in normal transparent adult lenses. Thus, our purpose was to test whether any part of the adult Soemmerring’s ring could be transparent and how this related to morphological factors. To study this, 16 Soemmerring’s rings were extracted from donor eye globes. After imaging, they were thickly sectioned sagittally in order to analyze the degrees of transparency of different areas. All samples were also histologically analyzed using alpha smooth muscle actin, Vimentin, wheat germ agglutinin and DAPI. Our results showed that many samples had some transparent areas, mostly towards the center of their cross-section. Of the factors that we analyzed, only lens fiber organization at the bow region and an increased area of mature lens fiber cells had a significant relation to the degree of transparency at the center. Thus, we can conclude that as Soemmerring’s rings mature, they can develop organized and transparent areas of lens cells. 相似文献
105.
106.
Zong-Han Wu Chun-Hung Chiu Chin-Chu Chen Charng-Cherng Chyau Chi-Hung Cheng 《International journal of molecular sciences》2023,24(1)
Fruiting bodies of Cordyceps cicadae (CC) have been reported to have a therapeutic effect in chronic kidney disease. Due to the rare and expensive resources from natural habitats, artificially cultivated mycelia using submerged liquid cultivation of CC (CCM) have been recently developed as an alternative to scarce sources of CC. However, little is known regarding potential protective effects of CCM against cyclosporine A (CsA)-induced acute nephrotoxicity in vivo and in vitro. In this study, male Sprague-Dawley rats were divided into six groups: control, CCM (40 mg and 400 mg/kg, orally), CsA (10 mg/kg, oral gavage), and CsA + CCM (40 mg and 400 mg/kg, orally). At the end of the study on day 8, all rats were sacrificed, and the blood and kidneys retrieved. CsA-induced acute nephrotoxicity was evident by increased levels of blood urea nitrogen (BUN). Levels of the endoplasmic reticulum (ER) resident chaperone glucose regulated protein 78 (GRP 78) were increased significantly in rats with acute nephrotoxicity. BUN and GRP 78 were significantly ameliorated in synchronous oral groups of CCM (40 or 400 mg/kg) plus CsA. Examination of hematoxylin and eosin stained kidney tissues revealed that the combined treatment of CCM slightly improved vacuolization in renal tubules upon CsA-induced damage. CsA-induced down-regulation of protein expression of magnesium ion channel proteins and transient receptor potential melastatin 6 and 7 were abolished by the combined treatment of CCM. CCM has the potential to protect the kidney against CsA-induced nephrotoxicity by reducing magnesium ion wasting, tubular cell damage, and ER stress demonstrated further by human renal proximal tubular epithelial cell line HK-2. Our results contribute to the in-depth understanding of the role of polysaccharides and nucleobases as the main secondary metabolites of CCM in the defense system of renal functions in CsA-induced acute nephrotoxicity. 相似文献
107.
Chin-Hao Li Tai-Ying Chen Chien-Chen Wu Shih-Hsuan Cheng Min-Yu Chang Wei-Hong Cheng Shih-Hau Chiu Chien-Chi Chen Ying-Chieh Tsai Deng-Jye Yang Jaw-Jou Kang Po-Lin Liao 《International journal of molecular sciences》2023,24(1)
Lacticaseibacillus paracasei strain PS23 (PS23) exhibits some probiotic properties. In this study, a genomic analysis of PS23 revealed no genes related to virulence or antibiotic resistance. Moreover, ornithine decarboxylase activity was not detected in vitro. In addition, PS23 was sensitive to the tested antibiotics. Genotoxicity tests for PS23 including the Ames test and chromosomal aberrations in vitro using Chinese hamster ovary cells and micronuclei in immature erythrocytes of ICR mice were all negative. Moreover, following a 28-day study involving repeated oral dose toxicity tests (40, 400, and 4000 mg/kg equal 1.28 × 1010, 1.28 × 1011, and 1.28 × 1012 CFU/kg body weight, respectively) using an ICR mouse model, no adverse effects were observed from any doses. In addition, supplementation with live or heat-killed PS23 ameliorates DSS-induced colonic inflammation in mice. Our findings suggest that PS23 is safe and has anti-inflammatory effects and may therefore have therapeutic implications. 相似文献
108.
Simultaneous delivery of antibiotics neomycin and ampicillin in drinking water inhibits fermentation of resistant starch in rats
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109.
Pham Phu Hieu Yao‐Ching Hsieh Jing‐Yuan Lin Bing‐Siang Huang Huang‐Jen Chiu 《International Journal of Circuit Theory and Applications》2018,46(4):868-881
An active‐clamp zero‐voltage‐switching (ZVS) buck‐boost converter is proposed in this paper to improve the performance of converter in light load condition. By employing a small resonant inductor, the ZVS range of switches could be adjusted to very light load condition. Moreover, 2 clamping capacitors are added in the converter to eliminate the voltage spike on the switches during transition. The operating principle of the proposed converter is analyzed, and the optimal design guide for full range ZVS is also provided. A 60‐W output prototype is experimentally built and tested in laboratory to verify the feasibility of proposed converter. The measured results show the critical ZVS operation of power switches at 1 and 0.7‐W output power for buck and boost mode, respectively. The peak conversion efficiency is up to 92.3%. 相似文献
110.
Huang‐Jen Chiu Yu‐Kang Lo Ching‐Chun Chuang Chung‐Yu Yang Shih‐Jen Cheng Min‐Chien Kuo Yi‐Ming Huang Yuan‐Bor Jean Yung‐Cheng Huang 《International Journal of Circuit Theory and Applications》2014,42(6):572-583
This paper presents a module‐integrated isolated solar micro‐inverter. The studied grid‐tied micro‐inverters can individually extract the maximum solar power from each photovoltaic (PV) panel and transfer to the AC utility system. A harmonic suppression technique is used to reduce the DC‐bus capacitance. Electrolytic capacitors are not needed in the studied solar micro‐inverter. High conversion efficiency, high maximum power point tracking accuracy and long lifespan can be achieved. The operation principles and design considerations of the studied PV inverter are analyzed and discussed. A laboratory prototype is implemented and tested to verify its feasibility. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献