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Effects of Alumina on Cristobalite Crystallization and Properties of Silica-Based Ceramic Cores

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journal of Materials Science & Technology 2017年第2期33卷 204-209页

作者： j.j.Liang Q.H.Lin X.Zhang T.jin Y.Z.Zhou X.F.Sun B.G.Choi I.S.Kim j.H.Do C.Y.jo Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Korea Institute of Materials Science Changwon 642-831Republic of Korea

In this work, the influences of alumina addition on cristobalite crystallization and properties of injec- tion molded silica-based ceramic cores were investigated. X-ray diffraction （XRD） was used to characterize phase transformations in the samples, and the XRD result indicated that the addition of alumina pro- moted crystallization of fused silica during sintering at 1180-1220 ℃ and thus increases the amount of cristobalite. The increased amount of cristobalite as well as alumina addition led to much more thermal dilation due to their higher coefficients of thermal expansion than that of fused silica. The flexural strengths at room temperature and 1500 ~C were tested, and it was shown that alumina addition could not affect room temperature strength, but decreased the flexural strength at 1500 ℃. In addition, deflection resis- tance during heating to high temperatures was investigated, and the result indicated that alumina addition speeded up high temperature softening of the samples. XRD and scanning electron microscopy equipped with energy dispersive spectrometry （SEMjEDS） analysis suggested that this softening behavior was related with viscous flow sintering which could be accelerated by the reaction of alumina and silica with a product of mullite.

关键词： Silica-based ceramic cores Alumina Cristobalite crystallization Properties

Efficacy and safety of modified tetracycline dosing in a quadruple therapy for Helicobacter pylori:A retrospective single center study

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World journal of Gastroenterology 2023年第22期29卷 3508-3518页

作者： Ying-Chao Sun Meng-jia Zhu Xue-Qin Chen Lei Yue Yi-Ru Zhao Xin-jie Wang john j Kim Qin Du Wei-Ling Hu Department of Gastroenterology Sir Run Run Shaw HospitalMedical SchoolZhejiang UniversityHangzhou 310016Zhejiang ProvinceChina Division of Gastroenterology Loma Linda University HealthLoma LindaCA 92354United States Department of Gastroenterology Zhejiang University School of Medicine Second Affiliated HospitalHangzhou 310009Zhejiang ProvinceChina Institute of Gastroenterology Zhejiang UniversityHangzhou 310016Zhejiang ProvinceChina

BACKGROUND Although highly effective as a component of Helicobacter pylori(***)treatment regimen,tetracycline is associated with a high incidence of medicationrelated adverse *** dosing of tetracycline as part of quadruple therapy may improve safety while providing comparable eradication *** To evaluate the efficacy and safety of modified dosing of tetracycline in patients receiving tetracycline and furazolidone-containing quadruple therapy in patients with *** *** Consecutive patients(10/2020-12/2021)who received tetracycline and furazolidone quadruple therapy for *** infection at Sir Run Run Shaw Hospital were *** patients received tetracycline,furazolidone,proton pump inhibitor,and bismuth for 14 d as primary or rescue *** tetracycline dose group received tetracycline 500 mg twice daily while standard group received 750 mg twice daily or 500 mg three times *** Three hundred and ninety-four patients[mean age=46.3±13.9,male=137(34.8%),and 309(78.4%)primary therapy]completed tetracycline and furazolidone quadruple therapy for *** infection including those who received modified tetracycline dose in 157 and standard doses in 118(750 mg twice daily)and 119(500 mg three times daily).Eradication rates in the modified tetracycline dose group were 92.40%and in the standard groups,eradication rates were 93.20%for 750 mg twice daily group and 92.43%for 500 mg three times daily group,respectively,without statistical difference(P=0.959).The incidence of adverse events was lower in the modified tetracycline dose(15.3%vs 32.3%and 29.4%;P=0.002)compared to the standard dose *** In a real-world experience,modified tetracycline dosing as part of tetracycline and furazolidone quadruple therapy for 14 d demonstrated high efficacy,comparable to standard tetracycline dose regimens,with a favorable safety profile.

关键词： Helicobacter pylori Tetracycline Furazolidone Eradication Penicillin allergy Bismuth quadruple therapy

Effect of tamoxifen on spermatogenesis and tubular morphology in rats

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Asian journal of Andrology 2004年第3期6卷 223-226页

作者： Urban j.A.D'Souza Department of Physiology School of Medical SciencesPPSP Universiti Sains Malaysia16150Kubang KerianKelantanMalaysia

Aim: To observe the effect of tamoxifen citrate on spermatogenesis and tubular morphology in rats. Methods: The effect of tamoxifen citrate i.g. at doses of 400 and 800 mg·kg·day-1 in 0.1 mL olive oil for 30 days on seminiferous tubular morphology, seminiferous epithelial diameter (STD), epithelial height (SEH), epididymal sperm count and percent abnormal sperm were evaluated at day 1, 12 and 36 after treatment. Controls were given the vehicle. Results: The higher dose resulted in tubular atrophy on day 31. The STD, SEH and sperm count were decreased and the abnormal spermatozoa increased in a dose-dependent manner with the maximal effect on day 36. Conclusion: Tamoxifen citrate induces tubular shrinkage and atrophy and sperm abnormality at a dose-dependent manner.

关键词： tamoxifen spermatozoa seminiferous tubule atrophy

Optical and luminescence characteristics of Eu^(3+)-doped B_2O_3:SiO_2:Y_2O_3:CaO glasses for visible red laser and scintillation material applications

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journal of Rare Earths 2018年第5期36卷 482-491页

作者： Pabitra Aryal C.R.Kesavulu H.j.Kim S.W.Lee Sang jun Kang j.Kaewkhao N.Chanthima B.Damdee Department of Physics Kyungpook National University College of Liberal Arts Semyung University Center of Excellence in Glass Technology and Materials Science (CEGM) Nakhon Pathom Rajabhat University Physics Program Faculty of Science and TechnologyNakhon Pathom Rajabhat University

Europium（Eu^3＋） doped glasses of chemical compositions（55-x）B2O3：10 SiO2：25 Y2O3：10CaO：xEu2O3,where x denotes mol% and ranges 0≤ x ≤ 2.5, were synthesized by adopting conventional melt quenching technique, Physical properties like density, molar volume, polaron radius, inter-ionic distance and field strength of the glass samples were investigated to assess the impact of Eu2O3. Optical and luminescence properties of the glasses were characterized with optical absorption, photoluminescence,X-ray induced emission spectra, temperature dependence emission spectra and decay times. judd-Ofelt（jO） intensity parameters（Ωλ） of the glasses were evaluated based on the absorption spectrum of 0.5 mol%. jO parameters, calculated from absorption spectra with thermal corrections on oscillator strength, were used to evaluate radiative properties such as radiative transition probability（AR）,branching ratio（βR）, stimulated cross section emission（σ） and radiative lifetime（τR） for 5D0→7 Fj（j = 0,1,2,3 and 4） transitions. The decay rate of 5D0 fluorescent level for all the glass samples was single exponential. Lifetimes of the 5D0 level were decreased with increasing concentrations of Eu^3＋ions from 0.05 mol% to 2.5 mol% which might be due to energy transfer through cross-relaxation in the glasses. The chromaticity coordinates（x, y） were similar for all BSYCaEu glasses and were located at the red region of CIE 1931 color chromaticity diagram. Hence, these results confirm that the Eu^3＋ doped BSYCaEu glasses could be useful for visible red lasers and glass scintillation applications.

关键词： BSYCaEu glasses judd-Ofeltintensity parameters Luminescence properties CIE color co-ordinates Glass scintillation Rare earths

An Efficient Unsupervised Learning Approach for Detecting Anomaly in Cloud

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Computer Systems Science & Engineering 2023年第4期45卷 149-166页

作者： P.Sherubha S.P.Sasirekha A.Dinesh Kumar Anguraj j.Vakula Rani Raju Anitha S.Phani Praveen R.Hariharan Krishnan Department of Information Technology Karpagam College of EngineeringCoimbatoreTamilnaduIndia Department of Computer Science and Engineering Karpagam Academy of Higher EducationCoimbatoreTamilnaduIndia Department of Computer Science and Engineering Koneru Lakshmaiah Education FoundationAndhra PradeshIndia Department of MCA CMR Institute of TechnologyBengaluruKarnatakaIndia Department of Computer Science and Engineering Prasad V.Potluri Siddhartha Institute of TechnologyAndhra PradeshIndia Department of Computer Science and Engineering Residency CollegeChennaiIndia

The Cloud system shows its growing functionalities in various industrial *** safety towards data transfer seems to be a threat where Network Intrusion Detection System(NIDS)is measured as an essential element to fulfill ***,Machine Learning(ML)approaches have been used for the construction of intellectual *** IDS are based on ML techniques either as unsupervised or *** supervised learning,NIDS is based on labeled data where it reduces the efficiency of the reduced model to identify attack ***,the unsupervised model fails to provide a satisfactory ***,to boost the functionality of unsupervised learning,an effectual auto-encoder is applied for feature selection to select good ***,the Naïve Bayes classifier is used for classification *** approach exposes the finest generalization ability to train the *** unlabelled data is also used for adoption towards data ***,redundant and noisy samples over the dataset are *** validate the robustness and efficiency of NIDS,the anticipated model is tested over the NSL-KDD *** experimental outcomes demonstrate that the anticipated approach attains superior accuracy with 93%,which is higher compared to j48,AB tree,Random Forest(RF),Regression Tree(RT),Multi-Layer Perceptrons(MLP),Support Vector Machine(SVM),and ***,False Alarm Rate(FAR)and True Positive Rate(TPR)of Naive Bayes(NB)is 0.3 and 0.99,*** compared to prevailing techniques,the anticipated approach also delivers promising outcomes.

关键词： Network intrusion detection system feature selection auto-encoder support vector machine(SVM) anomaly

Assembly and metrology of NIF target subassemblies using robotic systems

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High Power Laser Science and Engineering 2017年第4期5卷 14-19页

作者： K.-j.Boehm N.Alexander j.Anderson L.Carlson M.Farrell General Atomics P.O.Box 85608San DiegoCA 92186-5608USA

With European Laser Facilities such as the Extreme Light Infrastructure(ELI) and the Helmholtz International Beamline for Extreme Fields(HIBEF) scheduled to come online within the next couple of years, General Atomics, as a major supplier of targets and target components for the High Energy Density Physics community in the United States, is gearing up to meet their demand for large numbers of low cost targets. Using the production of a subassembly for the National Ignition Facility's fusion targets as an example, we demonstrate that through automation of assembly tasks, the design of targets and their experimental setup can be fairly complex while keeping the assembly time and cost as a minimum.A six-axis Mitsubishi robot is used in combination with vision feedback and a force–torque sensor to assemble target subassemblies of different scales and designs with minimal change of tooling, allowing for design flexibility and short assembly setup times. Implementing automated measurement routines on a Nikon NEXIV microscope further reduces the effort required for target metrology, while electronic data collection and transfer complete a streamlined target production operation that can be adapted to a large variety of target designs.

关键词： assembly automation hohlraum robotics target

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COSMIC RAYS

Chinese Physics C 2016年第10期40卷 421-428页

作者： j.j. Beatty j. Matthews S.P. Wakely Ohio State Univ. Louisiana State Univ. Univ. of Chicago

29.1. Primary spectra The cosmic radiation incident at the top of the terrestrial atmosphere includes all stable charged particles and nuclei with lifetimes of order 108 years or longer. Technically, ＂primary＂ cosmic rays are those particles accelerated at astrophysical sources and ＂secondaries＂ are those particles produced in interaction of the primaries with interstellar gas. Thus electrons, protons and helium, as well as carbon, oxygen, iron, and other nuclei synthesized in stars, are primaries. Nuclei such as lithium, beryllium, and boron （which are not abundant end-products of stellar nucleosynthesis） are secondaries. Antiprotons and positrons are also in large part secondary. Whether a small fraction of these particles may be primary is a question of current interest.

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Acoustic contamination assessment during the transition between the COVID-19 restrictions and reactivation:A exploratory analysis in Guayaquil

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Geography and Sustainability 2023年第2期4卷 138-149页

作者： Andrés Velastegui-Montoya Geancarlo Guerrero-Cabrera Sandra Gonzalez-Camba Yadira jaramillo-Lindao Ricardo Murillo-Portillo j.Hidalgo-Crespo Luis Encalada-Abarca Centro de Investigación y Proyectos Aplicados a las Ciencias de la Tierra(CIPAT) ESPOL Polytechnic UniversityP.O.Box 09-01-5863GuayaquilEcuador Facultad de Ingeniería en Ciencias de la Tierra(FICT) ESPOL Polytechnic UniversityP.O.Box 09-01-5863GuayaquilEcuador Geoscience Institute Federal University of Pará66075-110BelémBrazil Facultad de Ciencias Naturales y Matemáticas(FCNM) ESPOL Polytechnic UniversityP.O.Box 09-01-5863GuayaquilEcuador Sciences pour la Conception l’Optimisation et la Production(G-SCOP)Centre National de la Recherche Scientifique(CNRS)UniversitéGrenoble Alpes38000GrenobleFrance Facultad de Ingeniería Industrial Universidad de Guayaquil090150GuayaquilEcuador Centre of Geographical Studies Institute of Geography and Spatial PlanningUniversity of Lisbon1600-276LisbonPortugal Universidad Espíritu Santo SamborondónEcuador

Noise pollution is becoming a critical health risk for city *** 2020,the COVID-19 pandemic forced many cities to implement several mobility *** restrictions changed human activity patterns and decreased the noise levels and noise pollution that often affect urban *** the number of infections decreased,so did the outdoor activities,influencing the population’s perception of *** paper aims to evaluate the changes in noise levels associated with mobility restrictions between 2020 and 2021 in Guayaquil,*** study used crowdsourcing with the help of smartphones and mobile applications to collect geo-referenced environmental noise *** data was used to generate noise maps in different time ***,noise level maps were created using GIS-based tools to identify the urban areas that experienced the highest noise level variation during the study *** results show that the most significant noise increase occurred at ***,when analyzing noise level changes in different urban areas,the western area of Guayaquil was the one that experienced the most significant noise level *** inform the perception of noise pollution and could potentially serve as a reference for decision-makers during the proposal of public policies that ensure a better quality of life for its citizens.

关键词： Acoustic contamination Crowdsourcing Data scrubbing Kriging Noise map

3D-CNNHSR: A 3-Dimensional Convolutional Neural Network for Hyperspectral Super-Resolution

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Computer Systems Science & Engineering 2023年第11期47卷 2689-2705页

作者： Mohd Anul Haq Siwar Ben Hadj Hassine Sharaf j.Malebary Hakeem A.Othman Elsayed M.Tag-Eldin Department of Computer Science College of Computer and Information Sciences Majmaah UniversityAlmajmaah11952Saudi Arabia Department of Computer Science College of Science and Arts at MuhayelKing Khalid UniversitySaudi Arabia Department of Information Technology Faculty of Computing and Information TechnologyKing Abdulaziz UniversityP.O.Box 344Rabigh21911Saudi Arabia Department of Mathematics AL-Qunfudhah University CollegeUmm Al-Qura UniversityKSASaudi Arabia Faculty of Engineering and Technology Future University in EgyptNew Cairo11835Egypt

Hyperspectral images can easily discriminate different materials due to their fine spectral ***,obtaining a hyperspectral image(HSI)with a high spatial resolution is still a challenge as we are limited by the high computing *** spatial resolution of HSI can be enhanced by utilizing Deep Learning(DL)based Super-resolution(SR).A 3D-CNNHSR model is developed in the present investigation for 3D spatial super-resolution for HSI,without losing the spectral *** 3DCNNHSR model was tested for the Hyperion *** pre-processing of the HSI was done before applying the SR model so that the full advantage of hyperspectral data can be utilized with minimizing the *** key innovation of the present investigation is that it used 3D convolution as it simultaneously applies convolution in both the spatial and spectral dimensions and captures spatial-spectral *** clustering contiguous spectral content together,a cube is formed and by convolving the cube with the 3D kernel a 3D convolution is *** 3D-CNNHSR model was compared with a 2D-CNN model,additionally,the assessment was based on higherresolution data from the Sentinel-2 *** on the evaluation metrics it was observed that the 3D-CNNHSR model yields better results for the SR of HSI with efficient computational speed,which is significantly less than previous studies.

关键词： CNN super-resolution deep learning hyperspectral data computer vision