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When sexual selection in hosts benefits parasites

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Infectious Disease Modelling 2022年第3期7卷 561-570页

作者： Pooya Aavani sean H.Rice Department of Biological Sciences Texas Tech UniversityLubbockTXUSA Department of Biology Emory UniversityAtlantaGAUSA

In host-parasite coevolution,the parasite is selected to increase its infectivity while host is selected to resist the parasite *** is widely held that parasite-mediated sexual selection can further amplify the selective pressure on the host to overcome parasite *** this paper we focus on certain types of parasites,those that can impair the activity of the host immune function to prevent signs of *** show that the effect of sexual selection can actually reduce the selective pressure on the host immune response to adapt to the parasite *** design a simple mathematical model for a population of sexually reproducing organism in which individuals are choosy,preferring traits that are correlated negatively with immune system *** introduce to this population a parasite that can suppress activation of the host's immune *** results show that even though the host immune system is likely to ultimately evolve and adapt to the parasite infection,when sexual selection is part of this process,it can slow down this evolution on the host and give the parasite more time to get established.

关键词： Parasite-mediated sexual selection Immune response Initial spread of parasites Trade-off

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画廊

中国国家天文 2010年第8期4卷 140-143页

作者： sean walker 王伸（译）

明亮的火流星摄影／Dylan Etscorn4月18日黎明前的几小时．Dylan Etscorn在美国怀俄明州的科迪上空捕捉到了这颗明亮的流星，当时流星迅疾地穿过人马座处的银河中心。

关键词：画廊火流星怀俄明州人马座小时银河

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Avistack力助月球摄影

中国国家天文 2010年第2期4卷 126-128,129页

作者： sean walker 谢懿（译）

一个强大的免费软件能让你的月球照片更上一层楼。

关键词：月球摄影免费软件

Characterization of Deciliation-Regeneration Process of Tetrahymena Pyriformis for Cellular Robot Fabrication

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Journal of Bionic Engineering 2011年第3期8卷 273-279页

作者： Dal Hyung Kim sean E. Brigandi Paul Kim Doyoung Byun Min Jun Kim Department of Mechanical Engineering & Mechanics Drexel University Philadelphia PA 19104 USA Department of Aerospace Information Engineering Konkuk University Seoul 143-701 South Korea

magnetotactic Tetrahymena pyriformis GL （T. pyriformis） cells were created by the internalization of iron oxide nano particles and became controllable with a time-varying external magnetic field. Thus, T. pyriformis can be utilized as a cellular robot to conduct micro-scale tasks such as transportation and manipulation. To complete these tasks, loading inorganic or organic materials onto the cell body is essential, but functionalization of the cell membrane is obstructed by their motile organelles, cilia. Dibucaine HC1, a local anesthetic, removes the cilia from the cell body, and the functional group would be absorbed more efficiently during cilia regeneration. In this paper, we characterize the recovery of artificial magnetotactic T. pyriformis after the deciliation process to optimize a cellular robot fabrication process. After sufficient time to recover, the motility rate and the average velocity of the deciliated cells were six and ten percent lower than that of non-deciliated cells, respectively. We showed that the motile cells after recovery can still be controlled using magnetotaxis, making T. pyrfformis a good candidate to be used as a celIular robot.

关键词： Tetrahymena pyriformis deciliation cellular robot Helmholtz coil magnetic field magnetotaxis

Plant recruitment and survival as indicators of ecological restoration success in abandoned pasture land in Nurcoung,Victoria,Australia

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Ecological Processes 2013年第1期2卷 380-392页

作者： Singarayer K Florentine Jessica Gardner Friedrich P Graz sean Moloney School of Science Information Technology and Engineering Federation University AustraliaP.O.Box 663Mt.Helen 3353VICAustralia Greening Australia NC2 Building62 Main StreetNatimuk 3409Australia Department of Land Management Polytechnic of Namibia13Storch Str.P/Bag 13388WindhoekNamibia Department of Botany James Cook University1James Cook DrTownsville CityQLD 4811Australia

Introduction:One of the major impediments to developing better restoration strategies is the inadequate documentation of past restoration *** 2008,Greening Australia commenced ecological restoration on the Nurcoung property in Victoria to enhance local biodiversity,and in this paper we report on the habitat restoration outcomes in the three Ecological Vegetation Classes(EVC)found on this ***:Permanent sample plots(12×20 m)were randomly established in July 2010 in each of the restoration areas,with 9,10,and 24 plots demarcated in Shallow Sands Woodland(SSW),Heathy Woodland(HW),and Sandstone Ridge Woodlands(SRW),*** plots were prepared to include three seeded *** were assessed for seedling recruitment and survival in May 2010,April 2011,and May *** of individual seedling development included their height and cover,and their location within the ***:Our study shows that interaction between the age of the planted and direct-seeded vegetation and the nature of the EVC significantly affects the composition of plants and the soil surface in that species and,further,that soil cover parameters develop in different ways in the different experimental plots.A SIMPER analysis of soil cover parameters shows that most of the variation over the years of restoration is attributable to differences in the amount of bare soil recorded,rather than the amount of leaf-litter cover,and that these changes in soil cover parameters differ between EVCs over the sampling *** direct-seeding study shows that whilst most of the broadcast species were recruited,some species used in the Shallow Sands Woodland,the Heathy Woodland,and the Sandstone Ridge Shrubland did not show evidence of recruitment during the three sampling *** the density of most seedlings increased in subsequent sampling years,the planted species Callitris gracilis,Callitris rhomboidea,Hakea muelleriana,and Melaleuca lanceolata did not ***

关键词： soil planted seedling

Quantifying the bearing surface wear of retrieved hip replacements

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Biosurface and Biotribology 2019年第1期5卷 28-33页

作者： sean Bergiers Harry Hothi Robin Richards Johann Henckel Alister Hart Division of Surgery&Interventional Science Institute of Orthopaedics and Musculoskeletal ScienceUniversity College London and the Royal National Orthopaedic HospitalStanmoreUK

Accurate quantification of bearing material loss from retrieved metal-on-metal(MOM)hip replacements is key to understanding their *** methods are currently the only means of estimating volumetric wear from retrieved implants and numerous contrasting approaches to obtain these measures have been *** collection strategies have been thoroughly discussed and refined to minimise the effect of error incurring factors;however,there is an opportunity to optimise the current methods of estimating the pre-wear geometry and,therefore,improve the accuracy of wear volume *** automated analysis strategy to quantify volumetric wear is proposed in this study,which utilises the entire bearing surface to determine the implants pristine *** involves the iterative removal of geometrically effected data points to optimise the fit and size of a perfect *** fitted,this reference geometry is compared with the measured data,in its entirety,to calculate the volume change representative of the quantity of material *** the reliability of this parameter could influence the care of a million patients that remain with MOM hip *** validation of this method will dominate future work,ensuring that the accuracy and reliability of this approach are sufficient to provide clinically meaningful data.

关键词： wear surface meaningful

Macrophage inhibitory cytokine-1/growth differentiation factor-15 in premalignant and neoplastic tumours in a high-risk pancreatic cancer cohort

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World Journal of Gastroenterology 2020年第14期26卷 1660-1673页

作者： Robert sean O’Neill Sam Emmanuel David Williams Alina Stoita Department of Gastroenterology St Vincent’s HospitalSydney 2010Australia St Vincent’s Clinical School Faculty of MedicineUniversity of New South WalesSydney 2010Australia

BACKGROUND Pancreatic cancer(PC)is a leading cause of cancer related mortality worldwide,with poor survival due to late ***,biomarkers have limited use in early diagnosis of *** inhibitory cytokine-1 or growth differentiation factor-15(MIC-1/GDF15)has been implicated as a potential serum biomarker in PC and other *** To determine the role of MIC-1/GDF15 in detecting pre-malignant pancreatic lesions and neoplastic tumours in an asymptomatic high-risk cohort part of Australian Pancreatic Cancer Screening *** A feasibility prospective single centre cohort study was *** recruited for yearly surveillance with endoscopic ultrasound(EUS)had serial fasting blood samples collected before EUS for MIC-1/GDF15,C-reactive protein and carbohydrate antigen *** were stratified into five groups based on EUS findings:Normal;pancreatic cysts,branch-duct intraductal papillary mucinous neoplasm;diffuse non-specific abnormalities;and neoplastic ***-1/GDF15 serum levels were quantified using *** in whom EUS demonstrated abnormalities but not malignancy were closely followed up with magnetic resonance imaging(MRI)or computed *** One hundred twenty participants were prospectively recruited from ***-seven participants(39.2%)had an abnormal EUS and five participants(4.2%)were diagnosed with neoplastic tumours,three by EUS(two pancreatic and one liver)and two by MRI/computed tomography(breast cancer,bladder cancer),which were performed for follow up of abnormal *** serum MIC-1/GDF15 was a significant predictor of neoplastic tumours on receiver operator characteristic curve analysis[area under curve(AUC)=0.814,P=0.023].Baseline serum MIC-1/GDF15 had moderate predictive capacity for branch-duct intraductal papillary mucinous neoplasm(AUC=0.644)and neoplastic tumours noted on EUS(AUC=0.793),however this was not significant(P=0.188 and 0.081 respectively).Seria

关键词： Growth differentiation factor 15 Cytokines Pancreatic neoplasms Digestive system neoplasms Pancreatic diseases Biomarkers Diagnostic screening programs

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No property in man

No property in man

Sex differences in the influence of social context, salient social stimulation and amphetamine on ultrasonic vocalizations in prairie voles

作者： sean Wilentz.

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Integrative Zoology 2014年第3期9卷 280-293页

作者： sean T.MA Shanna L.RESENDEZ Brandon J.ARAGONA Department of Psychology Program in Neuroscience University of MichiganAnn ArborMIUSA

Prairie voles(Microtus ochrogaster)are a socially monogamous rodent species and their cooperative behaviors require extensive communication between *** use ultrasonic vocalizations(USVs)to communicate and because a prairie vole breeder pair must engage in extensive cooperation for successful reproduction,auditory communication may be critical for this ***,we sought to characterize USVs in adult male and female prairie voles,and to determine how these calls are influenced by social context,salient social stimuli and the psychostimulant drug of abuse amphetamine(AMPH).Here,we characterize prairie vole USVs by showing the range of frequencies of prairie vole USVs,the proportion of various call types,how these call types compare between males and females,and how they are influenced by social stimulation and *** caused a robust increase in the number of USVs in both males and females and there was a dramatic sex difference in the complexity of call structures of AMPH-induced USVs,with males emitting more elaborate ***,we show that novel(***)social cues evoked differential increases in USVs across sex,with males showing a much more robust increase in USV production,both with respect to the frequency and complexity of USV *** to an estrous female in particular caused an extraordinary increase in USVs in male *** data suggest that USVs may be a useful measure of social motivation in this species,including how social behaviors can be impacted by drugs of abuse.

关键词： amphetamine dopamine mate choice pair bonding ultrasonic vocalization