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Evaluation of the mechanisms of damage to flexible ureteroscopes and suggestions for ureteroscope preservation

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Asian Journal of Andrology 2005年第4期7卷 433-438,页

作者： P.Sooriakumaran R.Kaba h.O.Andrews N.P.N.Buchholz Department of Urology Royal Surrey County HospitalGuildfordGU2 7XXUK Department of Urology St Bartholomew's HospitalLondon EC1A 7BEUK

Aim： To investigate the causes and costs of flexible ureteroscope damage, and to develop recommendations to limit damage. Methods： The authors analysed repair figures and possible causes of damage to 35 instruments sent for repair to a leading UK supplier over a 1-year period, and calculated cost figures for maintenance of the instruments as opposed to repair and replacement costs. Results： All damages were handling-induced and therefore did not fall under the manufacturer＇s warranty： 28 % were damaged by misfiring of the laser inside the instrument; 72 %, mainly crushing and stripping of the ureteroscope shaft tube, were likely to have occurred during out-of-surgery handling, washing and disinfection. Seventeen （4 %） instruments were not repaired and consequently taken out of service due to the extensive costs involved. Eighteen （51%） ureteroscopes were repaired at an average cost of 10 833 USD. Conclusion： Damages to flexible ureteroscopes bear considerable costs. Most damages occur during handling between surgical procedures. Thorough adherence to handling procedures, and courses for theater staff and surgeons on handling flexible instruments may help to reduce these damages and prove a cost-saving investment. The authors provide a list of recommended procedural measures that may help to prevent such damages.

关键词： ureteroscopes manufacturer's assessment durability instrument handling

Contrasting microscopic interactions determine the properties of water/methanol solutions

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Frontiers of physics 2018年第1期13卷 51-56页

作者： Carmelo Corsaro Francesco Mallamace Sebastiano Vasi Sow-hsin Chen h. Eugene Stanley Domenico Mallamace CNR-IPCF Messina Istituto per i Processi Chimico-Fisici Viale F. Stagno D'Alcontres 37 98158 Messina Italy Dipartimento MIFT Sezione di Fisica Universita di Messina Viale F. Stagno D'Alcontres 31 98166 Messina Italy Department of Nuclear Science and Engineering Massachusetts Institute of Technology Cambridge MA 02139 USA Center for Polymer Studies and Department of Physics Boston University Boston MA 02215 USA Consorzio interuniversitario per lo sviluppo dei Sistemi a Grande Interfase - CSGI Via della Lastruccia 3 50019 Sesto Fiorentino Firenze Italy

herein we study the different microscopic interactions occurring in water/methanol solutions at dif- ferent methanol molar fractions, using NMR spctroscopy. Temperature was found to determine which interaction dominates. It was found that the mixing between water and methanol is non-ideal because of the presence of interactions like hydrophobicity and hydrophilicity. These results indicate that the competition between hydrophilic and hydrophobic interactions is different in different thermal regions, and that the physical properties of the solution are determined by the character of the solution itself, which in turn depends on the mole fraction of methanol and on the temperature.

关键词： aqueous solutions hydrophobicity NMR hydrophilicity

Synergistic O^(2-)/Li^(+) Dual Ion Transportation at Atomic Scale

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Research 2019年第1期2019卷 1260-1267页

作者： F.Q.Meng Q.h.Zhang A.Gao X.Z.Liu J.N.Zhang S.Y.Peng X.Lu L.Gu h.Li Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Materials Sun Yat-Sen UniversityGuangzhou 510275China College of Materials Science and Engineering Jiangxi University of Science and TechnologyJiangxi 341000China Songshan Lake Materials Laboratory DongguanGuangdong 523808China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

Te ion migration during electrochemical process is a fundamental scientifc issue for phase transition behavior and of technical importance for various functional devices,where cations or anions are active under electrical *** only one type of functional ion,O^(2-)or Li^(+),is activated due to their diferent migration energy barriers,cooperated by the valence change of other immobile ions in the host lattice matrix,e.g.,Co^(2+)/Co^(3+)and Mn^(3+)/Mn4+redox couples,owing to the charge *** we select spinel Li4Ti5O12 as anode and construct an all-solid-state battery under a transmission electron microscope;a synergistic transportation of O^(2-)and Li^(+)driven by an electrical bias was directly observed at the atomic scale.A small amount of oxygen anions was extracted frstly as a result of its lowest vacancy formation energy under 2.2 V,leading to the vertical displacement of *** to 2.7 V,an ordered phase with both Li-and O-defciency *** Li^(+)and O^(2-)ions are simultaneously extracted out from the[LiO_(4)]tetrahedra due to the electroneutrality *** migration paths of O and Li have been proposed and verifed by frst-principles *** results reveal a brand new synergistic ion migration manner and may provide up-to-date insights on the transportation process of lithium ion conductors.

关键词： synergistic battery migration

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反铁磁耦合记录介质的一级翻转曲线

物理学报 2008年第11期57卷 7287-7291页

作者：阴津华 C.h.hee 潘礼庆北京科技大学物理系 Data Storage Institute 5 Engineering Drive 1Singapore 117608

用实验测量和微磁计算的方法得到了反铁磁耦合记录介质的一级翻转曲线.利用微磁计算的目的是便于正确地理解一级翻转曲线分布图.因为它可以把一级翻转曲线分布图中不同部分与相应的磁化翻转联系起来.这样一级翻转曲线就能被用来分析复... 详细信息

用实验测量和微磁计算的方法得到了反铁磁耦合记录介质的一级翻转曲线.利用微磁计算的目的是便于正确地理解一级翻转曲线分布图.因为它可以把一级翻转曲线分布图中不同部分与相应的磁化翻转联系起来.这样一级翻转曲线就能被用来分析复杂磁化翻转及其相互作用的细节,而这种手段可以提供比通常用的ΔM方法更多的信息.

关键词：反铁磁耦合记录介质一级翻转曲线微磁学模拟

Second premolar agenesis is associated with mandibular form： a geometric morphometric analysis of mandibular cross-sections

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International Journal of Oral Science 2016年第4期8卷 254-260页

作者： Michael h Bertl Kristina Bertl Manuel Wagner Andre Gahleitner Andreas Stavropoulos Christian Ulm Philipp Mitteroecker Division of Orthodontics School of Dentistry Medical University of Vienna Vienna Austria Department of Periodontology Faculty of Odontology University of Malmo MalmoSweden Division of Oral Surgery School of Dentistry Medical University of Vienna Vienna Austria Department of Diagnostic Radiology Division of Osteoradiology General Hospital Medical University of Vienna Vienna Austria Department of Theoretical Biology University of Vienna Vienna Austria

The aim of this study was to compare mandibular form （i.e., size and shape） between patients with agenesis of the lower second premolar （P2） and a control group with no agenesis. Three hypotheses were tested：（h1） agenesis causes a change in mandibular morphology because of inadequate alveolar ridge development in the area of the missing tooth （mandibular plasticity）; （h2） agenesis is caused by spatial limitations within the mandible （dental plasticity）; and （h3） common genetic/ epigenetic factors cause agenesis and affect mandibular form （pleiotropy）. A geometric morphometric analysis was applied to cross-sectional images of computed tomography （CT） scans of three matched groups （n= 50 each）：（1） regularly erupted P2; （2） agenesis of P2 and the primary second molar in situ; and （3） agenesis of P2 and the primary second molar missing for 〉3 months. Cross-sections of the three areas of interest （first premolar, P2, first molar） were digitized with 23 landmarks and superimposed by a generalized Procrustes analysis. On average, the mandibular cross-sections were narrower and shorter in patients with P2 agenesis compared with that in the control group. Both agenesis groups featured a pronounced submandibular fossa. These differences extended at least one tooth beyond the agenesis-affected region. Taken together with the large interindividual variation that resulted in massively overlapping group distributions, these findings support genetic and/or epigenetic pleiotropy （h3） as the most likely origin of the observed covariation between mandibular form and odontogenesis. Clinically, reduced dimensions and greater variability of mandibular form, as well as a pronounced submandibular fossa, should be expected during the treatment planning of patients with P2 agenesis.

关键词： agenesis cross-sections geometric morphometrics mandibular form

Stability of Macroscopic Binary Systems

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Communications in Theoretical Physics 2019年第11期71卷 1335-1340页

作者： G.G.Adamian N.V.Antonenko h.Lenske V.V.Sargsyan Joint Institu te for Nuclear Research 141980 DubnaRussia Ins titut fur Theore tische Physik der Jus tus-Liebig—Uni versit Nt D-35392 GiessenGermany

The Darwin instability effect in the binary systems(di-planets, di-stars, and di-galaxies) is analyzed within the model based on the Regge-like laws. All possible binary stars are found satisfying the Darwin instability condition that requires to search for other mechanism triggering the merger of the contact binary objects. New analytical formulas are obtained for the orbital rotation period and the relative distance between components of the binary system. The decreasing and increasing periods as functions of mass asymmetry are related, respectively, with the non-overlapping and overlapping stage of the binary object evolution.

关键词： Regge laws binary stars and galaxies Darwin instability effect

Relations between SMBh Parameters and Jet Generation and Efficiency in Blazars

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Research in Astronomy and Astrophysics 2023年第11期23卷 67-83页

作者： h.Zhang h.J.Zhang Department of Physics Yunnan Normal UniversityKunming 650092China

We analyzed the relationship between several basic parameters describing supermassive black holes such as jet power,black hole spin,accretion disk magnetic field,black hole mass,*** found that there is a general correlation between these parameters,such as jet power is significantly positively correlated with black hole spin,while black hole mass is significantly negatively correlated with black hole *** apprehend these relationships,we consider the Blandford–Znajek model to be superior to the Blandford–Payne *** is also found that the intrinsic gamma luminosity of the FSRQs has a positive correlation with the accretion disk magnetic field,while the intrinsic gamma luminosity of the BL Lacs has a negative correlation with the accretion disk magnetic field.A feedback effect may exist between accretion disk accretion rate and magnetic field,which may be the key to the evolution between BL Lacs and *** is no significant difference in the jet power and jet generation efficiency of FSRQs and BL Lacs,which suggests that the jets are generated by the same *** contribution rate of accretion rate to jet generation efficiency is high,while the contribution rate of accretion rate to jet power is very low.

关键词： galaxies:evolution galaxies:fundamental parameters galaxies:jets

Variation of environmental neutron flux with altitude and depth of both water and soil

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Nuclear Science and Techniques 2004年第4期15卷 248-256页

作者： K.KOMURA N.K.AhMED A.h.EL-KAMEL A.M.M.YOUSEF Low Level Radioactivity Laboratory Kanazawa UniversityWake TatsunokuchiIshikawa 923-1224JapanPlrysics DepartmentFaculty of Science.South Valley UniversityKenaEgyptPhysics DepartmentFaculty of ScienceAssiut UniversityAssiutEgyptPhysics DepartmentFaculty of Science.South Valley UniversityKenaEgypt

Applying the extreme low-level γ-ray spectroscopic analysis the environmental neutron flux is measured using different moderator construction and environment through the reaction 197Au (n, γ) 198Au. The contribution of thermal and resonance neutrons is separated using the cadmium difference technique, while fast neutrons are measured by the paraffin moderator. The results of altitude dependence of the neutron flux are discussed. The thermal neutron flux near the surface of sea water is less than its value at 100 cm over ground near sea water, while the value over the surfaces of fresh water is higher than that near the surface of sea water. Also the thermal neutron flux at 5 cm soil depth increases, then decreases to its original value at 10 cm depth and still constant until 25 cm, then decreases rapidly to reach 27% of its original value at 60 cm depth. The soil compositions, corresponding neutron temperatures and effective absorption cross sections of earth are the most effective factors on the equilibrium region of thermal neutrons in the ground.

关键词：环境中子流金活化作用 γ射线光谱学环境放射学水土壤

Tiny insects against the weather flight and foraging patterns of Frankliniella schultzei (Thripidae) not altered by onset of rainfall

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Insect Science 2018年第6期25卷 1119-1127页

作者： Lachlan C.Jones Brodie J.Foster Michelle A.Rafter Gimme h.Walter School of Biological Sciences The University of QueenslandSt LuciaBrisbaneQueenslandAustrafia

To survive in nature,organisms may need to take direct action to mitigate specific dangers from their environmental *** flying insects are thought to be at particular risk from rainfall that would be of negligible concern to larger *** study species Frankliniella schultzei is a thrips that inhabits flowers and feeds mostly on petal tissue and *** found to respond in the laboratory to decreases in atmospheric pressure associated with cyclonic conditions (rather than merely heavy rainfall),their responses to conditions preceding rainfall have not been tested in the *** field sampling investigated the relationship between floral development and sites at which male,female,and larval thrips were generally present on sunny *** then designed a sampling strategy to test if these thrips can anticipate imminent rainfall or storms and so seek shelter deep within flowers,by sampling host flowers (in sections)on multiple days with different weather *** traps were used to intercept thrips in flight,thus providing a measure of flight behavior across different *** initial sampling found adult thrips primarily at the petal apex of anthesis-stage flowers where pollen is distributed. We subsequently found that rainfall,atmospheric pressure change,temperature,humidity and wind had no effect on flight behavior of E schultzei,or on their positions within *** findings suggest rainfall is not a serious hazard for *** thrips can survive raindrop collisions during flight,as impacts with water droplets are not expected to break the surface tension.

关键词： barometric pressure Frankliniella schultzei Malvaviscus arboreus rainfall shelter thrips