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Laparoscopic, Endoscopic and Robotic Surgery 2021年第3期4卷 85-89页

作者： Seth I.Noorbakhsh Jeffson C.h.chung Meghan T.Turner West Virginia University School of Medicine 1 Medical Center DriveMorgantownWV26506USA Department of Otolaryngology West Virginia University Health Sciences Center1 Medical Center DriveMorgantownWV26506USA

Transoral robotic surgery(TORS)is a minimally invasive technique for resection of tumors of the posterior pharyngeal ***,post-TORS cervical spondylodiscitis has been reported in the literature,with high morbidity and mortality.A 64-year-old female with underlying cervical disk disease underwent TORS resection of a posterior pharyngeal wall carcinoma without reconstruction in April *** one month post-operatively,the patient presented with clinical and radiographic signs of spondylodiscitis,epidural abscess,and *** patient was treated with antibiotic therapy and anterior cervical discectomy and *** patient recovered without neurologic deficit.A three-month post-treatment PET-CT scan showed no evidence of residual ***-operative cervical spondylodiscitis and meningitis are rare complications of TORS resection for posterior pharyngeal wall carcinomas,but the risk is increased in patients with underlying cervical disk *** such patients,perioperative antibiotic treatment and/or reconstruction should be considered to prevent neurologic complications and death.

关键词： Transoral robotic surgery Posterior pharyngeal wall carcinoma Spondylodiscitis Meningitis Surgical complication

Role of the tumor microenvironment in the pathogenesis of gastric carcinoma

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World Journal of Gastroenterology 2014年第7期20卷 1667-1680页

作者： hye Won chung Jong-Baeck Lim Department of Internal Medicine Institute of GastroenterologyYonsei University College of MedicineSeoul 135-720South Korea Department of Laboratory Medicine Yonsei University College of MedicineSeoul 135-720South Korea

Gastric carcinoma (GC) is the 4th most prevalent cancer and has the 2nd highest cancer-related mortality rate worldwide. Despite the incidence of GC has decreased over the past few decades, it is still a serious health problem. Chronic inflammatory status of the stomach, caused by the infection of helicobacter pylori (h. pylori) and through the production of inflammatory mediators within the parenchyma is suspected to play an important role in the initiation and progression of GC. In this review, the correlation between chronic inflammation and h. pylori infection as an important factor for the development of GC will be discussed. Major components, including tumor-associated macrophages, lymphocytes, cancer-associated fibroblasts, angiogenic factors, cytokines, and chemokines of GC microenvironment and their mechanism of action on signaling pathways will also be discussed. Increasing our understanding of how the components of the tumor microenviroment interact with GC cells and the signaling pathways involved could help identify new therapeutic and chemopreventive targets.

关键词： Tumor microenvironment Gastric carcinoma Inflammation helicobacter pylori Cytokine

Evaluation of spermatogenesis and fertility in F1 male rats after in utero and neonatal exposure to extremely low frequency electromagnetic fields

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Asian Journal of Andrology 2005年第2期7卷 189-194,页

作者： M.K.chung S.J.Lee Y.B.Kim S.C.Park D.h.Shin S.h.Kim J.C.Kim Reproductive Toxicology Division Korea Institute of ToxicologyKorea Research Institute of Chemical TechnologyDaejeon 305-600Korea College of Veterinary Medicine Chungbuk National UniversityCheongju 361-763Korea College of Veterinary Medicine Kyungpook National UniversityDaegu 702-701Korea College of Veterinary Medicine Chonnam National UniversityGwangju 500-757Korea

Aim:To determine whether in utero and neonatal exposure to a 60 hz extremely low frequency electromagnetic field (EMF) results in spermatotoxicity and reproductive dysfunction in the F1 offspring of ***:Age-matched, pregnant Sprague-Dawley rats were exposed continuously (21 h/day) to a 60 hz EMF at field strengths of 0 (sham control),5,83.3 or 500 μT from day 6 of gestation through to day 21 of *** experimentally generated magnetic field was monitored continuously (uninterrupted monitoring over the period of the study) throughout the ***:No exposure-related changes were found in exposed or sham-exposed animals with respect to the anogenital distance,preputial separation,testis weight,testicular histology,sperm count,daily sperm production, sperm motility,sperm morphology and reproductive capacity of F1 ***:Exposure of Sprague- Dawley rats to a 60 hz EMF at field strengths of up to 500 μT from day 6 of gestation to day 21 of lactation did not produce any detectable alterations in offspring spermatogenesis and fertility.

关键词： spermatogenesis electromagnetic fields prenatal exposure postnatal exposure rat

Selecting suitable sites for mountain ginseng(Panax ginseng)cultivation by using geographically weighted logistic regression

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Journal of Mountain Science 2017年第3期14卷 492-500页

作者： hAN hee JANG Kwang-min chung Joo-sang Department of Forest Engineering Resources and ManagementCollege of ForestryOregon State UniversityCorvallisOR 97331USA Department of Forest Sciences College of Agriculture and Life SciencesSeoul National UniversitySeoul 08826Republic of Korea Research Institute for Agriculture and Life Sciences Seoul National UniversitySeoul 08826Republic of Korea

With the well-being trends to pursue a healthy life, mountain ginseng(Panax ginseng) is rising as one of the most profitable forest products in South Korea. This study was aimed at evaluating a new methodology for identifying suitable sites for mountain ginseng cultivation in the country. Forest vegetation data were collected from 46 sites and the spatial distribution of all sites was analyzed using GIS data for topographic position, landform, solar radiation, and topographic wetness. The physical and chemical properties of the soil samples, including moisture content, p h, organic matter, total nitrogen, exchangeable cations, available phosphorous, and soil texture, were analyzed. The cultivation suitability at each site was assessed based on the environmental conditions using logistic regression(LR) and geographically weighted logistic regression(GWLR) and the results of both methods were compared. The results show that the areas with northern aspect and higher levels of solar radiation, moisture content, total nitrogen, and sand ratio are more likely to be identified as suitable sites for ginseng cultivation. In contrast to the LR, the spatial modeling with the GWLR results in an increase in the model fitness and indicates that a significant portion of spatialautocorrelation in the data decreases. A higher value of the area under the receiver operating characteristic(ROC) curve presents a better prediction accuracy of site suitability by the GWLR. The geographically weighted coefficient estimates of the model are nonstationary, and reveal that different site suitability is associated with the geographical location of the forest stands. The GWLR increases the accuracy of selecting suitable sites by considering the geographical variations in the characteristics of the cultivation sites.

关键词： Panax ginseng Site suitability Logistic regression Geographically weighted logistic regression Geographic Information System South Korea

Kinetics study on photochemical oxidation of polyacrylamide by ozone combined with hydrogen peroxide and ultraviolet radiation

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Journal of Environmental Sciences 2006年第4期18卷 660-664页

作者： REN Guang-meng SUN De-zhi chung Jong Shik School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Department of Chemical Engineering Pohang University of Science and Technology Pohang 790-784 South Korea

An investigation on the process of ozone combined with hydrogen peroxide and ultraviolet radiation has been carried out in order to establish the kinetics for photochemical oxidation of polyacrylamide （PAM） in aqueous solution. Effects of operating parameters, including initial PAM concentration, dosages of ozone and hydrogen peroxide, UV radiation and ph value on the photochemical oxidation of PAM, have been studied. There was an increase in photochemical oxidation rate of PAM with increasing of dosages of 03, h2O2 and ultraviolet radiation. Upon increasing of the initial PAM concentration, the photochemical oxidation rate of PAM decreased. Slight effect of ph value on the photochemical oxidation rate of PAM was observed in the experiments. The kinetics equation for the photochemical oxidation of PAM by the system has been established.

关键词： photochemical oxidation polyacrylamide kinetics ozone/hydrogen peroxide/ultraviolet radiation

Observational constraints on running vacuum model

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Chinese Physics C 2019年第2期43卷 132-137页

作者： Jin-Jun Zhang chung-Chi Lee Chao-Qiang Geng School of Physics and Information Engineering Shanxi Normal University DAMTP Centre for Mathematical Sciences University of Cambridge Department of Physics National Tsing Hua University National Center for Theoretical Sciences

We investigate the power spectra of the CMB temperature and matter density in the running vacuum model(RVM) with the time-dependent cosmological constant of A=3 vh^2+ Λ_0, where h is the hubble parameter. In this model, dark energy decreases in time and decays to both matter and radiation. By using the Markov chain Monte Carlo method, we constrain the model parameter v as well as the cosmological observables. Explicitly, we obtain v ≤1.54× 10^(-4)(68% confidence level) in the RVM with the best-fit χ_(RVM)~2 =13968.8, which is slightly smaller thanχ_(ΛCDM)~2= 13969.8 in the ΛCDM model of v = 0.

关键词： matter power spectrum running vacuum model CMB temperature spectrum cosmological constant

homogenization with the Quasistatic Tresca Friction Law:Qualitative and Quantitative Results

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Chinese Annals of Mathematics,Series B 2023年第5期44卷 781-802页

作者： Changqing YE Eric T.chung Jun-zhi CUI Department of Mathematics the Chinese University of Hong KongShatinHong Kong SARChina LSEC Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

Modeling of frictional contacts is crucial for investigating mechanical performances of composite materials under varying service *** paper considers a linear elasticity system with strongly heterogeneous coefficients and quasistatic Tresca friction law,and studies the homogenization theories under the frameworks of h-convergence and small ε-*** qualitative result is based on h-convergence,which shows the original oscillating solutions will converge weakly to the homogenized solution,while the author’s quantitative result provides an estimate of asymptotic errors in h^(1)-norm for the periodic *** paper also designs several numerical experiments to validate the convergence rates in the quantitative analysis.

关键词： homogenization Frictional contact mechanics Quasistatic Tresca frictionlaw

State-to-state Photoionization Dynamics of Vanadium Nitride by Two-color Laser Photoionization and Photoelectron Methods

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Chinese Journal of Chemical Physics 2013年第6期26卷 669-678,I0003页

作者： huang huang Zhi-hong Luo Yih.chung Chang Kai-chung Lau C. Y. Ng Department of Chemistry University of California Davis CA 95616 USA Department of Biology and Chemistry Oty University of Hone Kong Kowloon Hone Kong China

We have conducted a two-color visible-ultraviolet （VIS-UV） resonance-enhanced laser pho- toionization and pulsed field ionization-photoelectron （PFI-PE） study of gaseous vana- dium mononitride （VN） in the total energy range of 56900-59020 cm-1. The VN molecules were selectively excited to single rotational levels of the intermediate VN（D3h0, v＇=0） state by using a VIS dye laser prior to photoionization by employing a UV laser. This two-color scheme allows the measurements of rovibronically selected and re- solved PFI-PE spectra for the VN＋（X2A; v＋=0, 1, and 2） ion vibrational bands. By simulating the rotationally resolved PFI-PE spectra, J＋=3/2 is determined to be the lowest rotational level of the ground electronic state, indicating that the symmetry of the ground VN＋ electronic state is 2A3/2. The analysis of the PFI-PE spectra for VN＋ also yields accurate values for the adiabatic ionization energy for the formation of VN＋（X2A3/2）, IE（VN）=56909.5＋0.8 cm-1 （7.05588±0.00010 eV）, the vibrational fre- quency wc＋=1068.0±0.8 cm-1, the anharmonicity constant wc＋Xe＋=5.8±0.8 cm-1, the rotational constants Be＋=0.6563±0.0005 cm-1 and ae＋=0.0069±0.0004 cm-1, and the equi-librium bond length, re＋=1.529A, for VN＋（X2A3/2）; along with the rotational constants Bc＋=0.6578i0.0028 cm-1 and a＋=0.0085±0.0028 cm-1, and the equilibrium bond length re＋=1.527A for VN＋（X2As/2）, and the spin-orbit coupling constant A=153.3±0.8 cm-1 for VN＋（X2/k5/2,3/2）. The highly precise energetic and spectroscopic data obtained in the present study are valuable for benchmarking the predictions based on state-of-the-art ab initio quantum calculations.

关键词： Vanadium nitride Vanadium nitride cation Photoionization dynamics Two- color photoionization Pulsed field ionization-photoelectron Ionization energy Bond disso- ciation energy

Pheromone 3kPZS evokes context-dependent serotonin sexual dimorphism in the brain of the sea lamprey (Petromyzon marinus)

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Integrative Zoology 2015年第1期10卷 91-101页

作者： Yuwen chung-DAVIDSON huiyong WANG Anne MSCOTT Weiming LI Department of Fisheries and Wildlife Michigan State UniversityEast LansingMIUSA

Mature male sea lampreys(Petromyzon marinus)release a sex pheromone,3-keto-petromyzonol sulfate(3kPZS),that induces sexually dimorphic behavioral responses in ***,the neural mechanism of such responses is mostly *** examined the neurotransmitter serotonin(5-hydroxytryptamine,5-hT)and the expression of 5-hT1A receptors in the forebrain and brainstem of sea lamprey exposed to the vehicle(0.91 ppm methanol)or 10−10 M 3kPZS for 2 h using high performance liquid chromatography-electrospray ionization tandem mass spectrometry,immunohistochemistry and real-time quantitative polymerase chain *** to 3kPZS for 2 h increased 5-hT concentration in the forebrain of adult females,whereas 5-hT was not detected in the forebrain of adult *** the contrary,3kPZS exposure decreased 5-hT concentration in the brainstem of adult females and had no effect in adult *** exposure evoked context-dependent sexual dimorphism in brain 5-hT1A receptor immunoreactivity,but had no effect on 5-hT1A mRNA concentrations in the brain with 2 h exposure *** appears that in sea lamprey pheromone 3kPZS affects the 5-hT system in the brain in a context-dependent,sexually dimorphic manner.

关键词： 5-hT1A receptor liquid chromatography-electrospray ionization tandem mass spectrometry motor output real-time quantitative polymerase chain reaction

Liquid film falling behaviour on horizontal circular cylinder

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Journal of Central South University 2012年第5期19卷 1353-1358页

作者： chung han-shik K.Wusiman KIM Seong-soo B.Nasan h.Afrianto hafizur Rehman ChOI Du-youl JEONG hyo-min Department of Energy and Mechanical Engineering The Institute of Marine IndustryGyeongSang National UniversityTongYoungGyeongNam 650-160Korea Department of Mechanical and Precision Engineering GyeongSang National UniversityTongYoungGyeongNam 650-160Korea Fluid and Thermal Engineering Co. Ltd.GimHae-siGyungNam 621-843Korea

The flow pattern behaviour of falling liquid film over three horizontal cylinders was *** flows can take three forms:discrete droplets,individual jets,and continuous sheet,and special attention is paid to the effects of the physical properties and geometrical parameters of the first two forms(droplets and jets) because these forms are more important in heat-transfer behaviour and less research has been published for these forms,The flow modes and experimental results were successfully compared with previous experimental literatures,and also the effects of liquid flow rate,tube diameter,and tube spacing on departure site spacing,in both drop and jet modes,were evaluated in the low Galileo number and high viscosity fluid(cooking oil),to help developing criteria for determining falling film modes and their transitions,and to understand the heat transfer characteristics associated with each mode.

关键词： falling film flow mode cylinder