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Improving estimates of waning immunity rates in stochastic SIRS models with a hierarchical framework

Infectious Disease modelling 2023年第4期8卷 1127-1137页

作者： Punya Alahakoon james m.mcCaw Peter GTaylor School of mathematics and Statistics The University of MelbourneMelbourneAustralia Centre for Epidemiology and Biostatistics Melbourne School of Population and Global HealthThe University of MelbourneMelbourneAustralia School of Population Health University of New South WalesSydneyAustralia Kirby Institute University of New South WalesSydneyAustralia

As most disease causing pathogens require transmission from an infectious individual to a susceptible individual,continued persistence of the pathogen within the population requires the replenishment of susceptibles through births,immigration,or waning *** the introduction of an unknown infectious disease into a fully susceptible population where it is not known how long immunity is conferred once an individual recovers from ***,initially,the prevalence of disease increases(that is,the infection takes off),the number of infectives will usually decrease to a low level after the first major *** this post-outbreak period,the disease dynamics may be influenced by stochastic effects and there is a non-zero probability that the epidemic will die *** out in this period following the first major outbreak is known as an epidemic *** the disease does not die out,the susceptible population may be replenished by the waning of immunity,and a second wave may *** this study,we investigate if the rate of waning immunity(and other epidemiological parameters)can be reliably estimated from multiple outbreak data,in which some outbreaks display epidemic fade-out and others do *** generated synthetic outbreak data from independent simulations of stochastic SIRS models in multiple *** outbreaks faded-out and some did *** conducted Bayesian parameter estimation under two alternative approaches:independently on each outbreak and under a hierarchical *** conducting independent estimation,the waning immunity rate was poorly estimated and biased towards zero when an epidemic fade-out was ***,under a hierarchical approach,we obtained more accurate and precise posterior estimates for the rate of waning immunity and other epidemiological *** greatest improvement in estimates was obtained for those communities in which epidemic fade-out was observed.

关键词： estimates stochastic estimation

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A possible anorthositic continent of early mars and the role of planetary size for the inception of Earth-like life

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Geoscience Frontiers 2018年第4期9卷 1085-1098页

作者： james m.Dohm Shigenori maruyama motoyuki Kido Victor R.Baker The University museum The University of Tokyo Earth-Life Science Institute Tokyo Institute of Technology International Research Institute of Disaster Science Tohoku University Lunar and Planetary Laboratory The University of Arizona

The moon has an anorthositic primordial continental crust. Recently anorthosite has also been discovered on the martian surface. Although the occurrence of anorthosite is observed to be very limited in Earth＇s extant geological record,both lunar and martian surface geology suggest that anorthosite may have comprised a primordial continent on the early Earth during the first 600 million years after its formation. We hypothesized that differences in the presence of an anorthositic continent on an Earthlike planet are due to planetary size. Earth likely lost its primordial anorthositic continent by tectonic erosion through subduction associated with a kind of proto-plate tectonics（PPT）. In contrast, mars and the moon, as much smaller planetary bodies, did not lose much of their anorthositic continental crust because mantle convection had weakened and/or largely stopped, and with time, they had appropriately cooled down. Applying this same reasoning to a super-Earth exoplanet suggests that, while a primordial anorthositic continent may briefly form on its surface, such a continent will be likely transported into the deep mantle due to intense mantle convection immediately following its formation. The presence of a primordial continent on an Earth-like planet seems to be essential to whether the planet will be habitable to Earth-like life. The key role of the primordial continent is to provide the necessary and sufficient nutrients for the emergence and evolution of life. With the appearance of a ＂trinity＂ consisting of（1） an atmosphere,（2） an ocean, and（3） the primordial continental landmass, material circulation can be maintained to enable a ＂Habitable Trinity＂ environment that will permit the emergence of Earth-like life. Thus, with little likelihood of a persistent primordial continent, a super-Earth affords very little chance for Earth-like life to emerge.

关键词： Anorthosite on mars moon Habitable trinity Super-Earth Plate tectonics Origin of life

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Ductility demands on buckling-restrained braced frames under earthquake loading

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 255-268页

作者： Larry A.Fahnestock Richard Sause james m.Ricles Le-Wu Lu Department of Civil and Environmental Engineering ATLSS CenterLehigh UniversityBethlehemPennsylvaniaUSA Graduate Research Assistant Department of Civil and Environmental Engineering ATLSS CenterLehigh UniversityBethlehemPennsylvaniaUSA Professor

Accurate estimates of ductility demands on buckling-restrained braced frames(BRBFs)are crucial to performance-based design of *** analytical study on the seismic behavior of BRBFs has been conducted at the ATLSS Center,Lehigh University to prepare for an upcoming experimental *** analysis program DRAIN-2DX was used to model a one-bay,four-story prototype BRBF including material and geometric *** buckling- restrained brace(BRB)model incorporates both isotropic and kinematic *** static pushover and time- history analyses were performed on the prototype *** objectives for the BRBs were defined and used to evaluate the time-history analysis *** emphasis was placed on global ductility demands and ductility demands on the *** demands were compared with anticipated ductility *** analysis results,along with results from similar previous studies,are used to evaluate the BRBF design provisions that have been recommended for codification in the United *** results show that BRB maximum ductility demands can be as high as 20 to *** demands significantly exceed those anticipated by the BRBF recommended *** from the static pushover and time- history analyses are used to demonstrate why the ductility demands exceed those anticipated by the recommended provisions. The BRB qualification testing protocol contained in the BRBF recommended provisions is shown to be inadequate because it requires only a maximum ductility demand of at most *** to the testing protocol are recommended.

关键词： buildings buckling-restrained braced frames buckling-restrained braces structural response seismic response ductility demand seismic codes and standards

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基于CJP模型的疲劳裂纹扩展率曲线及应用方法

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机械工程学报 2018年第18期54卷 76-84页

作者：杨冰 james m N 西南交通大学牵引动力国家重点试验室成都610031 普利茅斯大学工程学院英国普利茅斯PL4 8AA

利用数字图像相关技术开展工业纯钛5种不同高宽比CT试样的疲劳裂纹扩展率试验,分别采用传统应力强度因子范围ΔK和基于CJP模型理论框架的新应力强度因子范围ΔKCJP对数据进行分析,得到的da/d N-ΔK和da/d N-ΔKCJP曲线均有效反映了试验... 详细信息

利用数字图像相关技术开展工业纯钛5种不同高宽比CT试样的疲劳裂纹扩展率试验,分别采用传统应力强度因子范围ΔK和基于CJP模型理论框架的新应力强度因子范围ΔKCJP对数据进行分析,得到的da/d N-ΔK和da/d N-ΔKCJP曲线均有效反映了试验数据分布规律,具有良好的拟合效果。相较于传统参量ΔK,ΔKCJP直接由裂尖位移场求解,无需进行修正即可用于材料疲劳裂纹扩展率描述,具有与CT试样高宽比无关的特性;作为ΔKCJP的两个组成参量,ΔKF、ΔKR与传统ΔK数据间均呈现出某种总体变化趋势,分别可用二次多项式和线性方程表征。构造了ΔKCJP与ΔK的关联函数,并由此推导出ΔKCJP表达式,为da/d N-ΔKCJP曲线在材料与结构的失效分析和安全评价中的应用提供了有效途径,拓宽了CJP模型的工程应用范围。

关键词： CJP模型裂尖位移场数字图像相关裂纹扩展率工业纯钛

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The Shishugou Fauna of the middle-Late Jurassic Transition Period in the Junggar Basin of Western China

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1115-1135页

作者： XU Xing james m.CLARK David A.EBERTH Philip J.CURRIE Centre for Vertebrate Evolutionary Biology Yunnan UniversityKunming 650500China Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China Department of Biological Sciences George Washington UniversityWashington DC20052USA Royal Tyrrell museum of Palaeontology Box 7500DrumhellerAlberta T0J 0Y0Canada Department of Biological Sciences University of Alberta 116 Street and 85 AvenueEdmontonAB T6G 2R3Canada

The middle-Late Jurassic transition period is a critical period for the evolution of terrestrial vertebrates,but the global fossil record from this time is relatively *** Shishugou Fauna of this period has recently produced significant fossil remains of dinosaurs and other vertebrate groups,some representing the earliest known members of several dinosaurian groups and other vertebrate groups and some representing the best-known specimens of their *** discoveries are significant for our understanding of the origin and evolution of several vertebrate *** dating indicates that the fauna is aged approximately 159-164 *** with other similarly-aged terrestrial faunas such as Shaximiao and Yanliao show both taxonomic similarities and differences between these faunas and indicate that the Junggar deposits might have preserved the most complete vertebrate fossil record for a middle-Late Jurassic Laurasian terrestrial fauna.

关键词： middle-Late Jurassic Shishugou Fauna Shishugou Formation terrestrial ecosystem Shaximiao Yanliao Junggar Basin

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ImPACT OF URBANIZATION ON STRUCTURE AND FUNCTION OF RIVER SYSTEm—Case Study of Shanghai,China

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Chinese Geographical Science 2006年第2期16卷 102-108页

作者： Philip james Research Institute for the Built and Human Environment School of Environment and Life Sciences University of Salford Greater manchester m5 4WT UK

Urbanization can affect the physical process of river growth, modify stream structure and further influence the functions of river system. Shanghai is one of the largest cities in the world, which is located in Changjiang (Yangtze) River Delta in China. Since the 1970s, the whole river system in Shanghai has been planned and managed by the Shanghai Water Authority. The primary management objectives in the last 30 years have been to enhance irrigation and flood-control. By using Horton-Strahler classification and Horton laws as a reference, a novel method of stream classification, in conjunction with the traditional and specially designed indicators, was applied to understanding the structure and functions of the river system in Shanghai. Correlation analysis was used to identify the interrelations among indicators. It was found that the impact of urbanization on the river system was significant although natural laws and physical characteristics marked a super-developed river system. There was an obvious correlation between the degree of urbanization and the abnormal values of some indicators. Urbanization impacts on river system such as branches engineered out, riverbank concreting and low diversity of river style were widely observed. Each indicator had distinct sensibility to urbanization so they could be used to describe different characteristics of urban river system. The function indicators were significantly related to structure indicators. Stream structure, described by fractal dimension and complexity of river system, was as important as water area ratio for maintaining river’s multi-function.

关键词： river system stream classification Horton law urbanization Shanghai

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Nanotrains and Self-Assembled Two-Dimensional Arrays Built from Carboranes Linked by Hydrogen Bonding of Dipyridones

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Nano Research 2008年第5期1卷 412-419页

作者： Takashi Sasaki Jason m.Guerrero Ashley D.Leonard james m.Tour Department of Chemistry Department of Mechanical Engineering and Materials ScienceRice UniversityMS 2226100 Main St.HoustonTexas 77005USA

The strong hydrogen bonding ability of 2-pyridones were exploited to build nanotrains on *** wheels on axles difunctionalized with 2-pyridone hydrogen bonding units were synthesized and displayed spontaneous formation of linear nanotrains by self-assembly on SiO_(2)or mica *** using atomic force microscopy confi rmed linear formations with lengths up to 5μm and heights within the range of the molecular height of the carborance-tipped axles.

关键词： Nanovehicles nanotrains 2-pyridone hydrogen bonding self-assembly

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Development of single-cell-level microfluidic tech no logy for long-term growth visualization of living cultures of mycobacterium smegmatis

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microsystems & Nanoengineering 2021年第3期7卷 63-72页

作者： Han Wang Gloria m.Conover Song-I Han james C.Sacchettini Arum Han Department of Biomedical Engineering School of MedicineTsinghua University100084 BeijingChina Department of Biochemistry and Biophysics Texas A&M UniversityCollege StationTX 77843USA Department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTX 77843USA Department of Biomedical Engineering Texas A&M UniversityCollege StationTX 77843USA Department of medical Education Health Sciences CenterTexas A&M UniversityBryanTX 77807USA

Analysis of growth and death kinetics at single-cell resolution is a key step in understanding the complexity of the nonreplicating growth phenotype of the bacterial pathogen mycobacterium ***,we developed a single-cell-resolution microfluidic mycobacterial culture device that allows time-lapse microscopy-based Iong-term phenotypic visualization of the live replication dynamics of *** technology was successfully applied to monitor the real-time growth dynamics of the fast-growing model strain mycobacterium smegmatis(***)while subjected to drug treatment regimens during continuous culture for 48 h inside the microfluidic device.A clear morphological change leading to significant swelling at the poles of the bacterial membrane was observed during drug *** addition,a small subpopulation of cells surviving treatment by frontline antibiotics was observed to recover and achieve robust replicative growth once regular culture media was provided,suggesting the possibility of identifying and isolating nonreplicative *** device is a simple,easy-to-use,and low-cost solution for studying the single-cell phenotype and growth dynamics of mycobacteria,especially during drug treatment.

关键词： fluid culture treatment mycobacterium

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Field experiments to improve the efficacy of gargoor (fish trap) fishery in Kuwait's waters

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Chinese Journal of Oceanology and Limnology 2012年第4期30卷 535-546页

作者：陈卫忠 AL-BAZ Ali BISHOP james m. AL-HUSAINI mohsen mariculture and Fisheries Department Kuwait Institute for Scientific Research P. O. Box 1638Salmiya 22017Kuwait

Fish traps were investigated to understand the effects of season, bait type, trap size, and trap soak time on catch rates, catch composition, and trap loss rates from march 2004 to September 2005, to improve the performance and management of Kuwait＇s gargoor （cage style fish trap） fishery, which used to be the nation＇s most important one in terms of value and landings volume. Catch rates were the highest in April/may （5 8 kg/trap haul） and again in December （7 kg/trap haul）. Bait type and trap size also affected catch rates and species composition. Of the seven baits tested, the best catch rates, 〉5 kg/trap haul, occurred with cuttlefish （Sepia pharaonis）, but wolf-herring （Chiroeentrus dorab） and mullet （Liza klunzingeri） also produced good results （4-5 kg/trap haul）. Within the five tested sizes, the two largest-sized traps captured more fish and larger size fish. Analysis of variance （ANOVA） showed significant differences of catch rate among traps with different baits as well as among traps of different sizes. Duncan test further revealed these differences between two specific baits and sizes. Cluster Analysis of species composition showed more differences among different baits than among different trap sizes. Longer soak times did not result in larger catch rates, but increased trap loss. About 10-day soak time resulted in trap loss 7%, while 40-day soak time could result in a loss of around 20%. Consequently, it is recommended that the gargoor be checked every 10 or fewer days. The average overall catch rate during the study period was lower than that of 1980s （4.5 vs. 5.8 kg/trap haul）, indicating a possible decline offish abundance in Kuwait＇s waters. It is recommended that the number of gargoor fishing boats and gargoors from each boat should be limited to allow stock rehabilitation.

关键词： field experiment fish trap improvement of efficacy catch rate Kuwait

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Response of saproxylic insect communities to logging history, tree species, stage of decay, and wood posture in the central Nearctic boreal forest

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Journal of Forestry Research 2018年第5期29卷 1365-1377页

作者： R.W.james Dennis Jay R.malcolm Sandy m.Smith m.Isabel Bellocq Faculty of Forestry University of Toronto 33 Willcocks St.Toronto ON M5S 3B3 Canada Departamento de Ecología Genética y EvoluciónFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires and IEGEBA (CONICET)Buenos Aires Argentina

Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest *** used a split-plot ANOVA design to analyze differences in selected saproxylic insects（all arthropod orders and dipteran and parasitic hymenopteran families） emerging from dead wood of sites with different logging histories（horse-logged,mechanically-logged and unlogged）,tree species（Populus and Picea）,stage of decay（early-and late-decay stages） and posture（standing and downed logs） in the boreal forest of central *** clear effects of logging history were seen for the studied taxa; however,interaction between logging history and other dead wood features was *** consistently emerged more from Populus than from Picea dead *** of the studied saproxylic families were more abundant in late-decay than in early-decay *** of the Cecidomyiidae,Ceratopogonidae,Empididae,mycetophilidae and Sciaridae families,and hymenopterans of the Diapriidae and Ichneumonidae families were significantly more abundant in downed than in standing dead *** contrast,mymaridae was most abundant in standing dead *** study provides evidence that some insects at high taxonomic levels respond differently to dead wood quality,and this could inform future management strategies in the boreal forest for the conservation of saproxylic fauna and their ecological functions.

关键词： Boreal forest Dead wood quality Forest harvesting High-level taxa Saproxylic insects

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