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Genetic variation and potential coinfection of Wolbachia among widespread Asian citrus psyllid (Diaphorina citri Kuwayama) populations

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Insect Science 2019年第4期26卷 671-682页

作者： Chia-Ching Chu Mark Hoffmann W. evan Braswell Kirsten S. Pelz-Stelinski Department of Entomology and Nematology University of Florida Gainesville Florida USA Citrus Research and Education Center University of Florida Lake Alfred Florida USA 3Department of Horticultural Sciences North Carolina State University Raleigh North Carolina USA Center for Plant Health Science and Technology USDA APHIS Edinburg Texas USA

Wolbachia can profoundly influence the survival, reproduction, and defenses of insect hosts. These interactions could potentially be harnessed for managing pests or insecttransmitted diseases. Diaphorina citri Kuwayama is a phloem-feeding pest capable of transmitting the putative causal agent of citrus greening, Candidatus Liberibacter asiaticus (CLas). Like many insects, D. citri is also infected with Wolbachia (wDi). Recent studies indicate that the relative abundance of wDi could be associated with the abundance of CLas, and that wDi may contribute to regulating expression of phage lytic cycle genes in CLas, suggesting the need for better understanding of wDi biology in general. This study investigated the genetic diversity of wDi among D. citri in populations spanning eleven countries and two U.S. territories. Six Wolbachia genes, wsp, ***, gatB, and hep A, were sequenced and compared across samples. Two prevalent wDi strains were identified across the samples, and screening of clone libraries revealed possible coinfection of wDi strains in specific populations. D. citri mitochondrial cytochrome oxidase subunit I gene (mtCOI) were more divergent between D. citri populations that were infected with different wDi strains or had different infection statuses (single infection vs. coinfection). While we could not eliminate the possibility that maternal transmission may contribute to such patterns, it is also possible that wDi may induce cytoplasmic incompatibility in their host. These fin dings should contribute to the understanding of wDi population ecology, which may facilitate manipulation of this endosymbiont for management of citrus greening disease worldwide.

关键词： bacteria genetic diversity Huanglongbing plant disease superinfection vertically transmitted endosymbionts

Development of a multivariate empirical model for predicting weak rock mass modulus

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International Journal of Mining Science and Technology 2015年第4期25卷 545-552页

作者： Kallu Raj R. Keffeler evan R. Watters Robert J. Agharazi Alireza Department of Mining Engineering University of Nevada RESPEC Consulting and Services University of Nevada Itasca Houston Inc.

Estimating weak rock mass modulus has historically proven difficult although this mechanical property is an important input to many types of geotechnical analyses. An empirical database of weak rock mass modulus with associated detailed geotechnical parameters was assembled from plate loading tests per- formed at underground mines in Nevada, the Bakhtiary Dam project, and Portugues Dam project. The database was used to assess the accuracy of published single-variate models and to develop a multivari- ate model for predicting in-situ weak rock mass modulus when limited geoteehnical data are available. Only two of the published models were adequate for predicting modulus of weak rock masses over lim- ited ranges of alteration intensities, and none of the models provided good estimates of modulus over a range of geotechnical properties. In light of this shortcoming, a multivariate model was developed from the weak rock mass modulus dataset, and the new model is exponential in form and has the following independent variables：（1） average block size or joint spacing, （2） field estimated rock strength, （3） dis- continuity roughness, and （4） discontinuity infilling hardness. The multivariate model provided better estimates of modulus for both hard-blocky rock masses and intensely-altered rock masses.

关键词： In-situ modulus Weak rock mass Preliminary design Elastic deformation

High-efficiency,large-area,topologyoptimized metasurfaces

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Light(Science & Applications) 2019年第1期8卷 749-757页

作者： Thaibao Phan David Sell evan W.Wang Sage Doshay Kofi Edee Jianji Yang Jonathan A.Fan Department of Electrical Engineering Stanford UniversityStanfordCA 94305USA Department of Applied Physics Stanford UniversityStanfordCA 94305USA Universite Clermont Auvergne Institut PascalBP 10448F-63000 Clermont-FerrandFrance CNRS UMR 6602Institut PascalF-63177 AubiereFrance

Metasurfaces are ultrathin optical elements that are highly promising for constructing lightweight and compact optical *** their practical implementation,it is imperative to maximize the metasurface *** optimization provides a pathway for pushing the limits of metasurface efficiency;however,topology optimization methods have been limited to the design of microscale devices due to the extensive computational resources that are *** introduce a new strategy for optimizing large-area metasurfaces in a computationally efficient *** stitching together individually optimized sections of the metasurface,we can reduce the computational complexity of the optimization from high-polynomial to *** a proof of concept,we design and experimentally demonstrate large-area,high-numerical-aperture silicon metasurface lenses with focusing efficiencies exceeding 90%.These concepts can be generalized to the design of multifunctional,broadband diffractive optical devices and will enable the implementation of large-area,high-performance metasurfaces in practical optical systems.

关键词： topology optimization surface

Glycaemic monitoring and control among high-risk patients with type 2 diabetes in Australian general practice during COVID-19

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Family Medicine and Community Health 2023年第3期11卷 62-85页

作者： Kirrilee Jane Barlow Paul P Fahey evan Atlantis School of Health Sciences Western Sydney UniversityKingswoodNew South WalesAustralia Discipline of Medicine Nepean Clinical SchoolFaculty of Medicine and HealthThe University of SydneyNepeanNew South WalesAustralia

Background The COVID-19 pandemic disrupted general practice worldwide,primarily due to public health measures that restricted access to care for chronic diseases,such as type 2 *** measures disproportionately affected higher risk groups with type 2 diabetes,such as older people and those with *** study aims to identify factors that may have influenced the rates of compliance with testing guidelines and target glycaemic control in Australian general practice settings during the COVID-19 *** We used a serial cross-sectional study design of patient record data from general practices representative of the Nepean Blue Mountains Local Health District between 2020 and *** patient records were analysed to determine percentages of subgroups with a blood glycaemic testing interval consistent with guidelines(≥1 within 15 months)and achieving target glycaemic control(by glycated haemoglobin of≤7%).Linear regression models were used to test the association between independent and dependent variables,and to generate regression coefficients and 95%CI,corrected for time *** Of the average 14356 patient records per month,55%were male,53%had a body mass index(BMI)<30 and 55%were aged 55–74 *** to testing guidelines slightly decreased(75–73%)but was positively associated with male sex(2.5%,95%CI 1.7%,3.4%),BMI≥30(9.6%,95%CI 8.8%,10.4%)and 55–74 years(7.5%,95%CI 6.6%,8.5%)and 75 years and over age groups(7.1%,95%CI 6.2%,7.9%).Mean percentage of patient records achieving target glycaemic control slightly increased and was negatively associated with male sex(-3.7%,95%CI-5.2%,–2.2%),but positively associated with 55–74 years(4.5%,95%CI 3.8%,5.1%)and 75 years and over age groups(12.2%,95%CI 4.5%,20.0%).Compliance to testing guidelines increased with each additional general practice per 10000 persons(8.4%,95%CI 4.9%,11.8%).Conclusions During the COVID-19 pandemic,people with type 2 diabetes in Australia continued to follow

关键词： patients testing slightly

Trauma systems in Canada:striving for quality across an expansive landmass

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Emergency and Critical Care Medicine 2023年第3期3卷 89-93页

作者： Natasha G.Caminsky evan G.Wong Division of General and Trauma Surgery McGill UniversityMontrealQuebecCanada

Although Canada has a universal health care program that provides free in-hospital services to all citizens,its vast landmass and nonstandardized prehospital and posthospital systems make delivering quality trauma care challenging,particularly to resource-limited rural *** article summarizes the strengths of the prehospital system,facility-based care,trauma network,trauma registry,rehabilitation,and governance/financing/quality assurance components of Canada’s trauma *** directions,including the use of telemedicine,standardization of practices,and resource optimization,are also ***’s trauma system is well developed,yet geography impedes equitable *** standardization and resource optimization are needed.

关键词： Trauma referral Trauma registry Trauma systems Universal health care

A Hunter-Gatherer Exercise Prescription to Optimize Health and Well-Being in the Modern World

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Journal of Science in Sport and Exercise 2021年第2期3卷 147-157页

作者： evan L.O’Keefe Carl J.Lavie Ochsner Clinical School The University of Queensland School of MedicineNew OrleansLAUSA Department of Cardiovascular Diseases John Ochsner Heart and Vascular Institute1514 Jefferson HighwayNew OrleansLA 70121-2483USA

There has been considerable innovation and advancement in the field of exercise and physical activity (PA).In regards to the battle against chronic non-communicable disease,however,we believe the model of PA that would prove most salu-tary is one closely mimicking that of our hunter-gatherer *** the purpose of longevity,the human body and our genetic makeup have been evolutionarily adapted to respond best to moderate amounts of high-intensity interval training,in conjunction with high amounts of low intensity ***,to optimize resiliency and cardiorespiratory fitness,a hunter-gatherer fitness regimen must include cross training targeted at flexibility,balance and *** not com-monly understood,the health benefits from exercise comprise a reverse *** endurance athletes residing on the furthest reaches of the PA spectrum appear to lose a substantial portion of the exercise-related longevity and cardiovascular benefits due to cardiac overuse ***,there is an emerging body of evidence suggesting leisure time exercise done with peers in a natural environment is significantly superior to that training done in *** idea of the "power of play" lends support to the ancestral model of PA whereby humans are evolutionary adapted to be highly social,outdoor creatures capable of a diverse range of PA at varying intensities.

关键词： Hunter-gatherer Cardiovascular disease Physical activity Exercise

Physical Properties of SiC Nanostructure for Optoelectronics Applications

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Journal of Renewable Materials 2021年第9期9卷 1519-1530页

作者： Mayyadah H.Mohsin Najwan H.Numan evan T.Salim Makram A.Fakhri Applied Science Department University of Technology-IraqBaghdad10066Iraq Laser and Optoelectronic Engineering Department University of Technology-IraqBaghdad10066Iraq

A SiC nanofilms have been deposited and investigated on quartz and silicon substrates using pulsed laser deposition technique with the 300 pulses of Nd:YAG laser at two different laser wavelengths of 1064 nm and 532 *** structural,morphological,and optical properties of the deposited nanostructure SiC were prepared and characterized as a function of the wavelengths of the used *** structural result shows four different pecks at(111),(200),(220),and(311)planes related to Nano *** transmission result presents that the optical energy gap value for the SiC nanostructure is depended on the wavelength of the used laser and it is found about the range(3.03 eV–3.23 eV).The investigations of the SEM and AFM show that the prepared SiC Nano-films having a grain size range(36.34–48.75)nm and roughness about 4.462 to 3.062 ***/Si hetero-junction devices show an enhanced performance at 532 nm.

关键词： Pulsed Laser deposition nanostructure 4H-SiC PLD heterostructure nanofilms

Snapshot Mueller spectropolarimeter imager

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Microsystems & Nanoengineering 2023年第5期9卷 271-279页

作者： Tianxiang Dai Thaibao Phan evan W.Wang Soonyang Kwon Jaehyeon Son Myungjun Lee Jonathan A.Fan Department of Electrical Engineering Stanford UniversityStanfordCA 94305USA Equipment R&D Team 4 Mechatronics ResearchSamsung Electronics Co.LtdGyeonggi-do 18848Republic of Korea

We introduce an imaging system that can simultaneously record complete Mueller polarization responses for a set of wavelength channels in a single image *** division-of-focal-plane concept combines a multiplexed illumination scheme based on Fourier optics together with an integrated telescopic light-field imaging ***-resolved imaging is achieved using broadband nanostructured plasmonic polarizers as functional pinhole *** recording of polarization and wavelength information on the image sensor is highly *** also develop a calibration approach based on a customized neural network architecture that can produce calibrated measurements in *** a proof-of-concept demonstration,we use our calibrated system to accurately reconstruct a thin film thickness map from a four-inch *** anticipate that our concept will have utility in metrology,machine vision,computational imaging,and optical computing platforms.

关键词： polarization image Snapshot

Effect of pumping chamber on performance of non-overload centrifugal pump

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Journal of Central South University 2015年第8期22卷 2989-2997页

作者：谷云庆牟介刚代东顺郑水华吴登昊蒋兰芳施瀚昱 WANG evan College of Mechanical and Engineering Zhejiang University of Technology Engineering Research Center of Process Equipment and Its Re-manufacturing of Ministry of Education(Zhejiang University of Technology) Zhijiang College Zhejiang University of Technology Institut National Polytechnique of Grenoble Joseph Fourier University

In order to specify the characteristics of un-overloaded centrifugal pumps, the IH100-65-200 pump was chosen as the model pump. Different calculation models for centrifugal pumps were established under different pumping chamber sectional parameters. In the numerical simulation of the centrifugal pumps flow field, the shaft power, head, efficiency, and the changes of the internal flow field under different sectional areas and sectional shapes were studied with the RNG k-ε turbulence model, and the influence of the pumping chamber section characteristics of the non-overloaded centrifugal pumps were analyzed. The results show that sectional areas have a significant impact on the non-overload characteristics of centrifugal pumps. The shaft power and head of centrifugal pump are increasing with a lager sectional area, by which the gradient of head curves decreases. The efficiency is improved under a large flow rate condition, but the head and the efficiency are reduced at a small flow rate. It is also observed that the sectional shapes have less influence on the shaft power, the hydraulic performance and flow field characteristics of a centrifugal pump.

关键词： centrifugal pumps sectional area sectional shape non-overload characteristics numerical simulation