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Local symmetries of finite type hypersurfaces in C^2 Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

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Science China Mathematics 2006年第11期49卷 1633-1641页

作者： kol■ Martin Depart. of Mathematical Analysis Masaryk University Janackovo Nam. 2A662 95 BrnoCzech Republic

The first part of this paper gives a complete description of local automorphism groups for Levi degenerate hypersurfaces of finite type in C2. It is also proved that, with the exception of hypersurfaces of the form v = |z.k, local automorphisms are always determined by their 1-jets. Using this result, the second part describes special normal forms which by an additional normaliz.tion eliminate the nonlinear symmetries of the model and allows to decide effectively about local equivalence of two hypersurfaces given in this normal form.

关键词： normal form finite type hypersurfaces local equivalence problem finite jet determination stability group.

Repeatability and reproducibility of corneal higher-order aberrations measurements after small incision lenticule extraction using the Scheimpfug-Placido topographer

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Eye and Vision 2024年第1期10卷 1-9页

作者： Rui Ning Rongrong Gao david PPiñero Jun z.ang Qingyi Gao Yili Jin Yiran Wang Chenxiao Wang Jinhai Huang Eye Hospital and School of Ophthalmology and Optometry Wenzhou Medical UniversityWenzhouZhejiangChina Eye Institute and Department of Ophthalmology Eye and ENT HospitalFudan UniversityShanghaiChina Group of Optics and Visual Perception Department of OpticsPharmacology and AnatomyUniversity of AlicanteAlicanteSpain NHC Key Laboratory of Myopia(Fudan University) Key Laboratory of MyopiaChinese Academy of Medical SciencesShanghaiChina Shanghai Research Center of Ophthalmology and Optometry ShanghaiChina

Background:To evaluate the precision of corneal higher-order aberrations measurements after small incision lenticule extraction(SMILE)using the Sirius Scheimpfug-Placido topographer(CSO,Italy).Methods:Seventy-fve eyes from 75 postoperative subjects were included in this prospective *** consecutive corneal aberrometric measurements were obtained with the Scheimpfug-Placido topographer by two experienced operators to assess intra-and inter-observer *** within-subject standard deviation(Sw),test-retest repeatability(TRT)and the intraclass correlation coefcient(ICC)were ***:For intraobserver repeatability of anterior and total corneal aberrations,all ICCs were more than 0.922,except for trefoil(0.722 to 0.768).The ICCs of total root mean square(RMS),coma z.3,±1),and spherical aberration z.4,0)were over 0.810 while higher-order RMS,trefoil z.3,±3),and astigmatism II z.4,±2)were below 0.634 for posterior corneal surface *** Sw values for all types of aberrations were equal to or below 0.07μ*** interobserver reproducibility,all TRT values were no more than 0.12μm,0.05μm,and 0.11μm for anterior,posterior,and total corneal aberrations,*** ICC values ranged from 0.875 to 0.989,from 0.686 to 0.976 and over 0.834 for anterior,posterior,and total corneal aberrations,***:The repeatability of measurements of anterior and total corneal aberrations with the Sirius system in corneas after SMILE surgery was high,except for *** was some variability in posterior corneal aberrometric *** reproducibility of corneal aberrometric measurements was observed between measurements of both examiners,except for trefoil,with poor to moderate reproducibility.

关键词： Sirius Higher-order aberrations Repeatability Reproducibility Small incision lenticule extraction

Experimental study of the dissipation of supersaturated TDG during the jet breakup process

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Journal of Hydrodynamics 2019年第4期31卷 760-766页

作者： Hong-cheng Xue Qian Ma Ran Li Ming-jun Diao david z. z.u Jing-ying Lu State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China Southwest Hydraulic Institute for Waterways Chongqing Jiaotong University Chongqing 400016 China Department of Civil and Environmental Engineering University of Alberta Edmonton Canada

Elevated levels of the total dissolved gas (TDG) may occur downstream the dams during the spill process to increase the incidence of the gas bubble disease for fish. With increasing numbers of cascade hydropower stations being constructed or planned, the cumulative effects of the TDG supersaturation become an increasingly prominent issue. Previous studies of the supersaturated TDG mainly focused on the generation process in the stilling basin downstream the dam while ignoring the saturation changes during the jet breakup process by assuming a 100% plunge-in-level. This assumption may lead to errors in the TDG generation predictions and the scientific assessments of the TDG supersaturation. Therefore, in this paper, physical experiments are conducted to analyz. the dissipation of the supersaturated TDG in the jet breakup process, and to establish a quantitative relation between the initial TDG level and the detention time of the jet in the air. These results indicate how the supersaturated TDG generated by an upstream dam affects the TDG generation and provide a scientific support for accurate predictions of the supersaturated TDG generation for high dam spills.

关键词： Jet breakup total dissolved gas (TDG) supersaturation high dam initial saturation dissipation

Impact of payment source, referral site, and place of residence on outcomes after allogeneic transplantation in Mexico

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World Journal of Transplantation 2024年第2期14卷 76-87页

作者： Andrés Gómez.De León Yesica A López.Mora Valeria García-z.rate Ana Varela-Constantino Sergio U Villegas-De Leon Xitlaly J Gonz.lez.Leal Raúl del Toro-Mijares Anna C Rodríguez.z.ñiga Juan F Barrios-Ruiz.Victor Mingura-Ledez.a Perla R Colunga-Pedraz. Olga G Cantú-Rodríguez.César H Gutiérrez.Aguirre Luz.Tarín-Arz.ga Elías E Gonz.lez.López.david Gómez.Almaguer Hematology Service Universidad Autónoma de Nuevo LeónFacultad de Medicina y Hospital Universitario Dr.JoséEleuterio GonzálezMonterrey 64460Nuevo LeónMexico Hemato-logy Service Clínica Gómez AlmaguerMonterrey 64710Nuevo LeónMexico Hematology Service Instituto Tecnológico de Estudios Superiores de MonterreyTec SaludEscuela de Medicina Ignacio SantosMonterrey 64710Nuevo LeónMexico

BACKGROUND The impact of social determinants of health in allogeneic transplant recipients in low-and middle-income countries is poorly *** observational study analyz.s the impact of place of residence,referring institution,and transplant cost coverage(out-of-pocket vs government-funded vs private insurance)on outcomes after allogeneic hematopoietic stem cell transplantation(alloHSCT)in two of Mexico's largest public and private *** To evaluate the impact of social determinants of health and their relationship with outcomes among allogeneic transplant recipients in *** In this retrospective cohort study,we included adolescents and adults≥16 years who received a matched sibling or haploidentical transplant from *** were selected without regard to their diagnosis and were sourced from both a private clinic and a public University Hospital in *** payment groups were compared:Out-of-pocket(OOP),private insurance,and a federal Universal healthcare program“Seguro Popular”.Outcomes were compared between referred and institution-diagnosed patients,and between residents of Nuevo Leon and *** outcomes included overall survival(OS),categoriz.d by residence,referral,and payment *** outcomes encompassed early mortality,event-free-survival,graft-versus-host-relapse-free survival,and non-relapse-mortality(NRM).Statistical analyses employed appropriate tests,Kaplan-Meier method,and Cox proportional haz.rd regression *** software included SPSS and R with tidycmprsk *** Our primary outcome was overall *** included 287 patients,n=164 who lived out of state(57.1%),and n=129 referred from another institution(44.9%).The most frequent payment source was OOP(n=139,48.4%),followed by private insurance(n=75,26.1%)and universal coverage(n=73,25.4%).No differences in OS,event-free-survival,NRM,or graft-versus-host-relapse-free survival were observed for patients dia

关键词： Hematopoietic cell transplant Social determinants of health Geography Haploidentical Out-of-pocket Financial toxicity Survival Health services and outcomes Hematopoietic malignancy Aplastic anemia

Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis

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Journal of Sport and Health Science 2024年第2期13卷 186-194页

作者： Andreas Konrad Shahab Aliz.deh Abdolhamid Daneshjoo Saman Hadjiz.deh Anvar Andrew Graham Ali z.hiri Rez. Goudini Chris Edwards Carina Scharf david George Behm Institute of Human Movement Science Sport and HealthGraz UniversityGraz A-8010Austria School of Human Kinetics and Recreation Memorial University of NewfoundlandSt.John’sNL A1C 5S7Canada Department of Sport Injuries and Corrective Exercises Faculty of Sport SciencesShahid Bahonar University of KermanKerman 76169-13439Iran

Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in ***,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch ***:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect siz.s by applying a random-effect ***,by applying a mixed-effect model,we performed the respective subgroup *** find potential relationships between stretch duration or age and effect siz.s,we performed a ***:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect siz.=-1.002;z.-12.074;95%confidence interval:-1.165 to-0.840;pz. ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be *** to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were

关键词： Flexibility Long-term stretching Stretch training

Experimental Study of Submergence Ratio on Local Scour Around a Square Pile in Steady Flow

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中国海洋大学学报:英文版 2023年第5期22卷 1277-1288页

作者： DU Shengtao WU Guoxiang LIANG Bingchen z.U david z.WANG Risheng School of Civil and Environmental Engineering Ningbo UniversityNingbo 315211China College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China College of Civil Engineering Shandong Jiaotong UniversityJinan 250357China

Scour around a submerged square pile was realiz.d experimentally in a steady flow to study the effects of flow depth on local *** depth to pile height ratios ranging from 1.5 to 5 in uniform sand and 2 to 5 in non-uniform sand were tested in the approaching flow velocity to critical velocity(larger than which the sediment particle is motivated)ratios of 0.56 and 1.03,*** influences of flow depth were investigated on the basis of analysis of the three-dimensional topography,temporal maximum scour depth,bed profile development,and equilibrium scour *** showed that the maximum scour depth was at the upstream corners of the pile other than at the stagnation *** evolutions of the maximum scour depth data in non-uniform sand were well fitted with a recent exponential function,which characteriz.d the initial,developing,and equilibrium stages of scour *** scour hole slopes upstream of the pile were found to be parallel to each other in the process of each test and were mainly governed by the sediment repose *** equilibrium scour depth varied slightly with flow depth when the submergence ratio was larger than 1 in uniform sand while it was 2 in non-uniform *** armoring effects of coarse sediment particles markedly reduced the sediment transport in non-uniform sand despite the 0.34 increment in non-uniformity.

关键词： non-uniform sand square pile local scour submerged scour depth

An acoustofluidic device for the automated separation of platelet-reduced plasma from whole blood

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Microsystems & Nanoengineering 2024年第3期10卷 293-303页

作者： z.ehan Ma Jianping Xia Neil Upreti Emeraghi david Joseph Rufo Yuyang Gu Kaichun Yang Shujie Yang Xiangchen Xu Jean Kwun Eileen Chambers Tony Jun Huang Thomas Lord Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNCUSA Department of Biomedical Engineering Duke UniversityDurhamNCUSA Department of Pediatrics Duke UniversityDurhamNCUSA Duke Transplant Center Department of SurgeryDuke University School of MedicineDurhamNCUSA

Separating plasma from whole blood is an important sample processing technique required for fundamental biomedical research,medical diagnostics,and therapeutic *** protocols for plasma isolation require multiple centrifugation steps or multiunit microfluidic processing to sequentially remove large red blood cells(RBCs)and white blood cells(WBCs),followed by the removal of small ***,we present an acoustofluidic platform capable of efficiently removing RBCs,WBCs,and platelets from whole blood in a single *** leveraging differences in the acoustic impedances of fluids,our device generates significantly greater forces on suspended particles than conventional microfluidic approaches,enabling the removal of both large blood cells and smaller platelets in a single *** a result,undiluted human whole blood can be processed by our device to remove both blood cells and platelets(>90%)at low voltages(25 Vpp).The ability to successfully remove blood cells and platelets from plasma without altering the properties of the proteins and antibodies present creates numerous potential applications for our platform in biomedical research,as well as plasma-based diagnostics and ***,the microfluidic nature of our device offers advantages such as portability,cost efficiency,and the ability to process small-volume samples.

关键词： remove separation removing

HYDRAULIC RESISTANCE OF SUBMERGED VEGETATION RELATED TO EFFECTIVE HEIGHT

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Journal of Hydrodynamics 2010年第2期22卷 265-273页

作者： WANG Pei-fang WANG Chao z.U david z. Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationCollege of Environmental Hohai University Nanjing 210098 China Department of Civil and Environmental Engineering University of Alberta Edmonton Canada T6G 2W2

Submerged vegetation has a significant impact on water flow *** investigations include the impact through adding drag resistance and increasing bottom roughness coefficient,which cannot elucidate the characters of real submerged *** evaluate the effects of submerged vegetation on water currents at different velocities,a laboratory experiment was conducted using three kinds of *** effective heights of these vegetations on varying flow velocities were *** equation describing the relationship between the normaliz.d resistance of the submerged plants and the Reynolds number based on the plant effective height was then established and used to calculate the hydraulic resistance parameters of submerged plants in different stages of growth.

关键词： hydraulic resistance submerged vegetation drag force effective height

Theoretical analysis and experimental study of oxygen transfer under regular and non-breaking waves

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Journal of Hydrodynamics 2013年第5期25卷 718-724页

作者：尹则高 david z.z.u 梁丙臣王乐 Shandong Province Key Laboratory of Ocean Engineering and Engineering College Ocean University of China Department of Civil and Environmental Engineering University of Alberta Department of Civil and Environmental Engineering University of Alberta Engineering College Ocean University of China

The dissolved oxygen concentration is an important index of water quality, and the atmosphere is one of the important sources of the dissolved oxygen. In this paper, the mass conservation law and the dimensional analysis method are employed to study the oxygen transfer under regular and non-breaking waves, and a unified oxygen transfer coefficient equation is obtained with consideration of the effect of kinetic energy and wave period. An oxygen transfer experiment for the intermediate depth water wave is performed to measure the wave parameters and the dissolved oxygen concentration. The experimental data and the least squares method are used to determine the constant in the oxygen transfer coefficient equation. The experimental data and the previous reported data are also used to further validate the oxygen transfer coefficient, and the agreement is satisfactory. The unified equation shows that the oxygen transfer coefficient increases with the increase of a parameter coupled with the wave height and the wave length, but it decreases with the increase of the wave period, which has a much greater influence on the oxygen transfer coefficient than the coupled parameter.

关键词： dissolved oxygen regular and non-breaking waves oxygen transfer coefficient