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51.
Kazuo Tsubota Stephen C. Pflugfelder Zuguo Liu Christophe Baudouin Hyo Myung Kim Elisabeth M. Messmer Friedrich Kruse Lingyi Liang Jimena Tatiana Carreno-Galeano Maurizio Rolando Norihiko Yokoi Shigeru Kinoshita Reza Dana 《International journal of molecular sciences》2020,21(23)
Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint. 相似文献
52.
Effect of Sintering Temperature on Thermoelectric Properties of p‐Bi2Te3 Alloys Produced by Gas Atomization 下载免费PDF全文
Babu Madavali Hyo‐Seob Kim Min‐Gyu Choi Gi‐Chan Park Jar‐Myung Koo Hyeon‐Taek Son Soon‐Jik Hong 《International Journal of Applied Ceramic Technology》2016,13(2):245-251
In this research, p‐type Bi2Te3–75% Sb2Te3 thermoelectric alloy powders were produced by gas atomization and subsequently sintered by hot pressing at different temperatures. The grain growth of the hot‐pressed samples was observed with increasing sintering temperature from 380°C to 460°C. The compressive strength increased with increasing hot‐pressing temperature due to the high relative density of bulk samples obtained at high temperatures. The effect of sintering temperature on thermoelectric (TE) properties was studied. The maximum power factor 3.48 mW/mK2 was obtained for the sample hot pressed at 420°C due to the resulting high electrical conductivity and enhanced Seebeck coefficient values. 相似文献
53.
Mechanical Properties of Submicrometer‐Grained Transparent Yttria Ceramics by Hot Pressing with Hot‐Isostatic Pressing 下载免费PDF全文
Lin Gan Young‐Jo Park Haneul Kim Jin‐Myung Kim Jae‐Woong Ko Jae‐Wook Lee 《International Journal of Applied Ceramic Technology》2016,13(4):678-684
Here, we report the fabrication and mechanical properties of submicrometer‐grained (0.29–0.58 μm) transparent yttria ceramics by hot pressing combined with hot‐isostatic pressing. The effects of the grain size on the microhardness and the fracture toughness were studied. An unusual decrease of the fracture toughness with an increase in the grain size was revealed, which may be attributed to the different grain size dependence of the fracture behavior of the ZrO2‐doped yttria ceramics compared to that of other yttria ceramics. The microhardness and fracture toughness of the transparent yttria ceramics were found to be better than those of the large‐grained yttria ceramics. 相似文献
54.
Two donor–acceptor-type alternating copolymers consisting of 2,1,3-benzoselenadiazole and carbazole derivatives with thiophene or selenophene π-bridges were synthesized by Suzuki cross-coupling polymerization, and their optical, electrochemical, and photovoltaic properties were compared. The selenophene π-bridged copolymer (PCz-DSeBSe) exhibited a smaller band-gap (1.82 eV) than the thiophene-bridged polymer (PCz-DTBSe; 1.89 eV). PCz-DSeBSe also showed a deeper highest occupied molecular orbital energy level (−5.36 eV) than PCz-DTBSe (−5.20 eV). Moreover, the PCz-DSeBSe thin film showed higher crystallinity and hole mobility than the PCz-DTBSe thin film. Organic photovoltaic devices were fabricated using the polymers as the donors and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor. The device using PCz-DSeBSe showed a higher open circuit voltage (Voc), short circuit current density (Jsc), and power conversion efficiency (PCE) than that using PCz-DTBSe. The fabricated indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/PCz-DSeBSe:PC71BM/LiF/Al device showed the maximum PCE of 2.88% with a Jsc of 7.87 mA/cm2, an Voc of 0.80 V, and a fill factor of 0.50 under AM 1.5G irradiation (100 mW/cm2). 相似文献
55.
Hyung Ik Lee Seok Kim Jin Hoe Kim Myung Hee Yun Jei-Won Yeon Ji Man Kim 《Carbon》2009,47(4):1043-1293
A mesoporous carbon material, CMK-1 was successfully functionalized with carboxymethylated polyethyleneimine (CMPEI) by a simple adsorption method. The physicochemical properties of the polymer-carbon composite (denoted as CMPEI/CMK-1) were investigated by X-ray diffraction, N2 adsorption-desorption and X-ray photoelectron spectroscopy (XPS). The adsorption behaviors of Cu(II) ion on the CMK-1 and CMPEI/CMK-1 materials were examined under the batch-type experimental conditions. The CMPEI/CMK-1 material showed a typical Langmuir isotherm with a 10-fold increase in adsorption capacity, compared to that of CMK-1. In the case of 0.02 mM Cu(II) solution, the copper ions were completely removed by utilizing the CMPEI/CMK-1 material both at pH values of 3 and 5. The CMPEI/CMK-1 material also exhibited a remarkably high distribution coefficient value (Kd = 2.75 × 105). The results from XPS depth profiles before and after the copper-ion adsorption indicated that the CMPEI and the adsorbed Cu(II) ions were uniformly distributed within the CMK-1 particles. 相似文献
56.
Hee Jung Kim Ji Eun Park Myung Gil Choi Sangdoo Ahn Suk-Kyu Chang 《Dyes and Pigments》2010,84(1):54-58
A novel, Hg2+-selective chemosensor was prepared via Mannich reaction of dichlorofluorescein with piperazinyl-coumarin moiety. The dichlorofluorescein–coumarin derivative exhibited well-defined Hg2+-selective chromogenic behavior, indicated by a green to pink colour change in solution, as well as fluorogenic signalling. Significant changes in fluorescence of the dichlorofluorescein subunit were analyzed in reference to the rather constant coumarin emission as an internal standard yielding Hg2+ selectivity. The Hg2+ selectivity of the chemosensor was not appreciably affected by the presence of common coexisting alkali, alkaline earth, and transition metal ions. The detection limit of the dichlorofluorescein–coumarin conjugate for the determination of Hg2+ ions was 4.3 × 10−6 mol L−1 and the conjugate dye could be used as a chemosensor for the analysis of Hg2+ ions in aqueous environments. 相似文献
57.
Xinjian Yuan Myung Bok Kim Young Ho Cho Chung Yun Kang 《Metallurgical and Materials Transactions A》2012,43(6):1989-2001
The changes in tensile strength and pitting corrosion resistance of transient liquid-phase (TLP)-bonded joints for a duplex
stainless steel with MBF-80, MBF-30, and MBF-35 as functions of holding time and filler were interpreted with respect to the
bond microstructure. Using MBF-80 after 300 seconds, the fracture strength of the joint reached the maximum value. The failure
was dependent on the interplay between the reduction in residual liquid and the increase in interface precipitates. After
3600 seconds, the joint strength had the minimum value. At the same conditions, the tensile strength for MBF-80 was low compared
with MBF-35 and MBF-30. In contrast with the tensile strength, the joint produced with MBF-80 for 3600 seconds exhibited the
best corrosion resistance. Among the fillers used, the corrosion resistance of the joint using MBF-80 close to that of the
substrate could be related intimately to the existence of Cr in this filler. 相似文献
58.
Joon‐Myung Kang Hong‐Taek Ju Mi‐Jung Choi James Won‐Ki Hong Jun‐Gu Kim 《International Journal of Network Management》2009,19(6):491-511
Mobile devices (e.g. mobile handsets or PDAs) have gained much functionality and intelligence with the growth of mobile network technologies and the increased use of mobile services. As a consequence, mobile devices have become more complex and many related problems have occurred. Specifically, sudden rebooting and freezing problems caused by software faults decrease the availability of the mobile device and cause inconvenience to end‐users. To solve such problems, academia and industry have focused on Open Mobile Alliance (OMA) Device Management (DM); this method is the international de facto standard for mobile device management. In this paper, we propose a software fault management method to remotely determine and correct problems of mobile devices based on OMA DM. We present a definition of management objects and a method to collect them from mobile devices using the OMA DM protocol. We also present a method for debugging and correcting software faults using the collected information. Finally, we present a prototype implementation and performance evaluation to validate our proposed method. Results of the performance evaluation show that our proposed method is efficient and scalable in regard to network traffic overhead and response time. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
59.
Panaxfurayne A and B, biologically novel tetrahydrofuranic polyacetylene glycosides, were founded from roots of Panax ginseng C. A. Meyer (Araliaceae). To study the contents of panaxfurynes A and B, a quantitative analysis method was developed using ultra performance liquid chromatography (UPLC) coupled with photo diode array detector. The dried (65 °C, 72 h) and powdered sample (5 g) was extracted with ethanol (15%, 100 ml) for 30 min at 50 °C and concentrate. The constituents were separated using an isocratic mobile phase consisting acetonitrile (16%) in water for 10 min on a ODS column. The contents of panaxfuraynes A and B in the roots of Panax quinquefolium, Panax japonicum, Panax notoginseng and P. ginseng were found to less than 3 and 2 ng/g approximately, respectively. The constituents were not detected from P. japonicum. 相似文献
60.
Syadaruddin Syachrani Hyung Seok Jeong Vajra Rai Myung Jin Chae Tom Iseley 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2010,25(6):681-688
Proper functioning of culverts is not only critical to protecting the transportation system from flooding but also critical to maintaining the expected service life of the overall transportation system. During the service life of culverts, they deteriorate due to many reasons such as corrosion caused by road salt, blockage by debris and sediment, poor construction techniques, etc. Trenchless technologies have been used by several State Departments of Transportation (DOTs) to rehabilitate deteriorated drainage structures without disrupting the traffic and within a relatively short span of time. These technologies provide many benefits in terms of cost, time, quality, and expected service life. However, the safety aspects of these techniques have not been discussed and documented in detail probably due to the complexity and the lack of safety standards and specifications directly associated with the techniques. This paper discusses the application of a risk assessment framework to assess potential safety issues of currently available trenchless technologies for culvert rehabilitation. The findings of the study will provide additional information to improve the decision making process in selecting and planning culvert rehabilitation projects. 相似文献