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A simple,sensitive and non-destructive technique for characterizing bovine dental enamel erosion:attenuated total reflection Fourier transform infrared spectroscopy

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International Journal of Oral Science 2016年第1期8卷 54-60页

作者： In-Hye kim Jun Sik Son bong Ki Min Young Kyoung kim Kyo-Han kim Tae-Yub Kwon Department of Dental Science Graduate SchoolKyungpook National UniversityDaeguKorea Korea Textile Development Institute DaeguKorea Center for Research Facilities Yeungnam UniversityGyeongsanKorea Department of Conservative Dentistry School of DentistryKyungpook National UniversityDaeguKorea Department of Dental Biomaterials School of DentistryKyungpook National UniversityDaeguKorea

Although many techniques are available to assess enamel erosion in vitro, a simple, non-destructive method with sufficient sensitivity for quantifying dental erosion is required. This study characterized the bovine dental enamel erosion induced by various acidic beverages in vitro using attenuated total reflection Fourier transform infrared （ATR-FTIR） spectroscopy. Deionized water （control） and 10 acidic beverages were selected to study erosion, and the pH and neutralizable acidity were measured. Bovine anterior teeth （110） were polished with up to 1 200-grit silicon carbide paper to produce flat enamel surfaces, which were then immersed in 20 mL of the beverages for 30 min at 37 ℃. The degree of erosion was evaluated using ATR-FTIR spectroscopy and Vickers＇ microhardness measurements. The spectra obtained were interpreted in two ways that focused on the ~1, ~3 phosphate contour： the ratio of the height amplitude of ~3 P04 to that of/11 P04 （Method 1） and the shift of the v3 P04 peak to a higher wavenumber （Method 2）. The percentage changes in microhardness after the erosion treatments were primarily affected by the pH of the immersion media. Regression analyses revealed highly significant correlations between the surface hardness change and the degree of erosion, as detected by ATR-FTIR spectroscopy （P〈0.001）. Method 1 was the most sensitive to these changes, followed by surface hardness change measurements and Method 2. This study suggests that ATR- FTIR spectroscopy is potentially advantageous over the microhardness test as a simple, non-destructive, sensitive technique for the quantification of enamel erosion.

关键词： acidic beverage enamel erosion Fourier transform infrared spectroscopy microhardness sensitivity

Neonatal erythema multiforme associated with a rotavirus infection:A case report

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世界临床病例杂志 2023年第24期11卷 5749-5754页

作者： Jung Jae kim joon Kee Lee Department of Pediatrics Chungbuk National University HospitalCheongju 28644South Korea Department of Pediatrics Chungbuk National UniversityCheongju 28644South Korea

BACKGROUND Erythema multiforme(EM)is an extremely rare condition in neonates,and studies suggest its association with certain infections and neonatal vaccinations;however,few specific etiological agents have been ***,a common pathogenic gastrointestinal virus in the neonatal period that is preventable via vaccination,has not been identified as a possible *** report the case of a neonate who was referred for skin lesions presenting as EM,where a meticulous workup identified rotavirus as the sole causative *** SUMMARY A 14-day-old male infant was admitted to our hospital with a 1-day history of skin *** medical history or medication intake was *** for the complaint of skin lesions,the caregivers denied any abnormal *** tests,including routine laboratory evaluations,were performed to identify the cause of skin *** tests for Immunoglobulin M for Toxoplasma,Rubella,Cytomegalovirus,Herpes Simplex Virus,and Epstein-Barr virus viral-capsid antigen were all *** polymerase chain reaction(PCR)tests for respiratory viruses and bacterial pathogens were negative(including the severe acute respiratory syndrome coronavirus 2).Multiple PCR tests for gastrointestinal viruses and bacterial pathogens demonstrated evidence of rotavirus *** growth was reported in the blood and urine *** patient received intravenous fluids for hydration;meanwhile,no other medications were *** lesions improved rapidly without specific treatment,and full recovery was achieved within a *** The possibility of rotavirus,a major cause of pediatric gastrointestinal infections,being a trigger for neonatal EM should be considered.

关键词： Erythema multiforme Gastrointestinal diseases Neonate Rotavirus Skin abnormalities Case report

Optimal design of FRMSM to decrease detent force

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Journal of Central South University 2011年第2期18卷 458-464页

作者： JANG Ki-bong PYO Se-Ho AN Ho-Jin kim Gyu-Tak School of Mechatronics Changwon National University

An optimal configuration of the flux-reversal linear synchronous motor (FRLSM) with the optimal number of attachment permanent magnets (PMs) was presented. The optimal model of 2 000 N was designed to reduce the detent force by redesigning the air-gap structure and skewing. The design parameters,mover PMs and stator core,were selected for optimal design by DOE. The thrust and the detent force of the designed optimal models were compared by finite element analysis (FEA). As a result,the thrust of the optimal model is slightly decreased by 1.97% compared with the basic model,and the detent force of the optimal model is greatly decreased by 88.47% compared with the basic model.

关键词： flux-reversal linear synchronous motor detent force thrust design of experiment skew and overhang

Parallel Iterative FEM Solver with Initial Guess for Frequency Domain Electromagnetic Analysis

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Intelligent Automation & Soft Computing 2023年第5期36卷 1585-1602页

作者： Woochan Lee Woobin Park Jaeyoung Park Young-joon kim Moonseong kim Department of Electrical Engineering Incheon National UniversityIncheon22012Korea Department of Computer Engineering Hongik UniversitySeoul04066Korea Department of Electronic Engineering Gachon UniversitySeongnam13120Korea Department of IT Convergence Software Seoul Theological UniversityBucheon14754Korea

The finite element method is a key player in computational electromag-netics for designing RF(Radio Frequency)components such as *** frequency-domain analysis is fundamental to identify the characteristics of the *** the conventional frequency-domain electromagnetic analysis using FEM(Finite Element Method),the system matrix is complex-numbered as well as indeﬁ*** iterative solvers can be faster than the direct solver when the solver convergence is guaranteed and done in a few ***,such complex-numbered and indeﬁnite systems are hard to exploit the merit of the iterative *** is also hard to beneﬁt from matrix factorization techniques due to varying system matrix parts according to ***,it is hard to adopt conventional iterative solvers even though the system matrix is sparse.A new parallel iterative FEM solver for frequency domain analysis is implemented for inhomogeneous waveguide structures in this *** this implementation,the previous solution of the iterative solver of Matlab(Matrix Laboratory)employ-ing the preconditioner is used for the initial guess for the next step’s solution *** overlapped parallel stage using Matlab’s Parallel Computing Toolbox is also proposed to alleviate the cold starting,which ruins the convergence of early steps in each parallel *** experiments based on waveguide structures have demonstrated the accuracy and efﬁciency of the proposed scheme.

关键词： Computational electromagnetics numerical simulation ﬁnite element method parallel processing iterative solvers

Effect of In Composition on Two-Dimensional Electron Gas in Wurtzite AlGaN/InGaN Heterostructures

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Chinese Physics Letters 2010年第11期27卷 188-190页

作者： kim bong-Hwan PARK Seoung-Hwan LEE Jung-Hee MOON Yong-Tae Department of Electronics Engineering Catholic University of Daegu Hayang Kyeongsan Kyeongbuk 712-702 R. Korea School of Electrical Engineering and Computer Science Kyungpook National University Daegu 702-701 R. Korea LG Corporate Institute of Technology 16 Woomyeon-dong Seocho-gu Seoul 137-14-0 R. Korea

The effect of In composition on two-dimensional electron gas in wurtzite AlGaN/InGaN heterostructures is theoretically investigated. The sheet carrier density is shown to increase nearly linearly with In mole fraction x, due to the increase in the polarization charge at the AlGaN/InGaN interface. The electron sheet density is enhanced with the doping in the AlGaN layer. The sheet carrier density is as high as 3.7×1013 cm^-2 at the donor density of 10×1018 cm^-3 for the HEMT structure with x=0.3. The contribution of additional donor density on the electron sheet density is nearly independent of the In mole fraction.

关键词： Condensed matter: electrical magnetic and optical Electronics and devices Semiconductors Surfaces interfaces and thin films Condensed matter: structural mechanical & thermal Nanoscale science and low-D systems

High resolution impedance manometric findings in dysphagia of Huntington's disease

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World Journal of Gastroenterology 2012年第14期18卷 1695-1699页

作者： Tae Hee Lee joon Seong Lee Wan Jung kim Institute for Digestive Research Soon Chun Hyang College of MedicineSeoul 140-743South Korea

Conventional manometry presents significant challenges,especially in assessment of pharyngeal swallowing,because of the asymmetry and deglutitive movements of oropharyngeal *** only provides information about intraluminal pressure and thus it is difficult to study functional details of esophageal motility *** technology of solid high resolution impedance manometry(HRIM),with 32 pressure sensors and 6 impedance sensors,is likely to provide better assessment of pharyngeal swallowing as well as more information about esophageal motility ***,the clinical usefulness of application of HRIM in patients with oropharyngeal dysphagia or esophageal dysphagia is not *** experienced a case of Huntington's disease presenting with both oropharyngeal and esophageal dysphagia,in which HRIM revealed the mechanism of oropharyngeal dysphagia and provided comprehensive information about esophageal dysphagia.

关键词： Dysphagia Esophagus High resolution impedance manometry Huntington's disease Oropharynx

Inhibitory effect of Patrinia scabiosaefolia on acute pancreatitis

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World Journal of Gastroenterology 2006年第7期12卷 1110-1114页

作者： Sang-Wan Seo Cheung-Seog Park Seung-Heon Hong Kang-Beom Kwon Hyoung-Chul Moon bong-keun Song Kyung-Yo kim Young-Min Park Ho-joon Song Hyung-Min kim Sung-Joo Park Department of Herbology School of Oriental MedicineWonkwang UniversityIksanJeonbuk 570-749South Korea Department of Microbiology College of MedicineKyung Hee UniversitySeoulSouth Korea Department of oriental Pharmacy College of Oriental PharmacyWonkwang UniversityIksanJeonbuk 570-749South Korea Department of Physiology School of Oriental MedicineWonkwang UniversityIksanJeonbuk 570-749South Korea Department of Clinical laboratory Wonkwang University Gwangju medical CenterGwangjuJeonnam 503-310South Korea Department of Microbiology and Immunology and Medical Research Instituteand Laboratory of Dendritic Cell Differentiation and RegulationPusan National University College of MedicineBusanSouth Korea Department of Pharmacology College of Oriental MedicineKyung Hee UniversitySeoulSouth Korea

AIM： To investigate the effect of Patrinia scabiosaefolia （PS） on the cholecystokinin （CCK） octapeptide-induced acute pancreatitis （AP） in rats.METHODS： Wistar rats weighing 240-260 g were divided into three groups：（1） Normal saline-treated group; （2） treatment with PS at 100 mg/kg group, in which PS was administered orally, followed by subcutaneous administration of 75μg/kg CCK octapeptide three times after 1, 3 and 5 h, and this whole procedure was repeated for 5 d; （3） treatment with saline group, in which the protocols were the same as in treatment group with PS. We determined the pancreatic weight/ body weight ratio, the levels of pancreatic HSP60, HSP72 and the secretion of pro-inflammatory cytokines. Repeated CCK octapeptide treatment resulted in the typical laboratory findings of experimentally induced pancreatitis.RESULTS： PS reduced the pancreatic weight/body weight ratio, the levels of serum amylase and lipase, and inhibited expressions of pro-inflammatory cytokines in the CCK octapeptide-induced AP. Furthermore, PS pretreatment increased the pancreatic levels of HSP60 and HSP72.CONCLUSION： Pretreatment with PS has an antiiinflammatory effect on CCK octapeptide-induced AP.

关键词： Acute pancreatitis Patrinia scabiosaefolia CCK octapeptide

Precore/core region mutations of hepatitis B virus related to clinical severity

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World Journal of Gastroenterology 2016年第17期22卷 4287-4296页

作者： Hong kim Seoung-Ae Lee Seung Yeon Do Bum-joon kim Department of Biomedical Sciences Microbiology and Immunology Liver Research Institute and Cancer Research Institute College of Medicine Seoul National University

Despite the availability of an effective vaccine, hepatitis B virus (HBV) infection remains a major health problem, with more than 350 million chronically infected people worldwide and over 1 million annual deaths due to cirrhosis and liver cancer. HBV mutations are primarily generated due both to a lack of proofreading capacity by HBV polymerase and to host immune pressure, which is a very important factor for predicting disease progression and therapeutic outcomes. Several types of HBV precore/core (preC/C) mutations have been described to date. The host immune response against T cells drives mutation in the preC/C region. Specifically, preC/C mutations in the MHC class II restricted region are more common than in other regions and are significantly related to hepatocellular carcinoma. Certain mutations, including preC G1896A, are also significantly related to HBeAg-negative chronic infection. This review article mainly focuses on the HBV preC/C mutations that are related to disease severity and on the HBeAg serostatus of chronically infected patients.

关键词： Hepatitis B virus infection Precore/core mutations Hepatocellular carcinoma HBeAg serostatus Disease severity

Fabrication of miniature helical gears by powder extrusion using gas atomized Zn-22%Al powder

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Transactions of Nonferrous Metals Society of China 2012年第6期22卷 1313-1321页

作者： LEE Kyung-Hun LEE Jung-Min PARK joon-Hong kim Byung-Min Precision Manufacturing Systems Division Pusan National University30 Jangjeon-DongKumjeong-GuBusan 609-735Korea Dongnam Regional Division Korea Institute of Industrial Technology1274 Jisa-dongGangseo-guBusan 618-230Korea Department of Mechanical Engineering DONG-A University840 Hadan 2-dongSaha-guBusan 604-714Korea Engineering Research Center for Net Shape and Die Manufacturing Pusan National University30 Jangjeon-DongKumjeong-GuBusan 609-735Korea

Powder extrusion, which is based on the superplastic behavior of Zn-22%A1 eutectoid alloy, was proposed to reduce the forming load and promises to provide fine microstructures in the manufacture of miniature helical gears. The specifications of the helical gears were as follows： module, 0.3; number of teeth, 12; and helix angle, 15°. Compacted powders were consolidated by sintering and solution heat treatment. The consolidated billets consisted of lamellar and fine-grained microstructures. Extrusion experiments were carried out under the following conditions： temperature, 250 ℃; strain rates, 2.36× 10-3 s^-1 and 1.18× 10^-1 s-1. The mechanical properties of the extruded helical gears were investigated by measurement of the Vickers hardness and extrusion load, and by scanning electron microscopy.

关键词： helical gear powder extrusion gas atomized Zn-22%A1 powder superplasticity