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High resolution tracking of adult horseshoe crabs Limulus polyphemus in a New Hampshire estuary using fixed array ultrasonic telemetry

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current Zoology 2010年第5期56卷 599-610页

作者： Winsor H.WATSON Ⅲ christopher c.c.abot Department of Biological Sciences University of New Hampshire Department of Biology Plymouth State University

While several studies have documented the large-scale, seasonal movements of horseshoe crabs, little is known about their fine-scale, daily movement patterns. In this study we used a fixed array ultrasonic telemetry system to track the movements of 12 male and 16 female horseshoe crabs in the Great Bay estuary, New Hampshire. Data were obtained during the mating season, as well as during the remainder of the summer and fall, in the years 2005-2008. During the mating season animals were often, but not always, active during the high tides when they were approaching and leaving the spawning beaches. On average, both males and females approached mating beaches during 33% of the high tides they experienced and they most often made the tran- sition from being inactive to active during the last two hours of an incoming tide. From April-October horseshoe crabs were significantly more active during high tide periods vs low tide periods, with no clear preference for diurnal vs nocturnal activity. After the mating season ended horseshoe crabs continued to move into shallower water at high tide and then return to deeper water at low tide. Observations by ScUBA divers suggest that during these excursions into the mudflats horseshoe crabs were digging pits in the sediment while foraging for food. Thus, the tidal rhythm of activity that has been so well documented during the mating season probably persists into the fall, and primarily involves foraging activities

关键词： Telemetry Tracking Movements Mating Foraging Estuary

High-cycle Fatigue Life Extension of Glass Fiber/Polymer composites with carbon Nanotubes

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 167-173页

作者： christopher S Grimmer c K H Dharan Berkeley composites Laboratory University of California 5135 Etcheverry Hall Berkeley CA94720-1740 USA

The present work shows that the addition of small volume fractions of multi-walled carbon nanotubes （cNTs） to the matrix results in a significant increase in the high-cycle fatigue life. It is proposed that carbon nanotubes tend to inhibit the formation of large cracks by nucleating nano-scale damage zones. In addition, the contribution to energy absorption from the fracture of nanotubes bridging across nano-scale cracks and from nanotube pull-out from the matrix are mechanisms that can improve the fatigue life. An energy-based model was proposed to estimate the additional strain energy absorbed in fatigue. The distributed nanotubes in the matrix appear to both distribute damage as well as inhibit damage propagation resulting in an overall improvement in the fatigue strength of glass fiber composites.

关键词： glass fiber composites carbon nanotubes fatigue strain energy

IgE-Mast cell mediated allergy: a sensor of food quality

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Signal Transduction and Targeted Therapy 2024年第1期9卷 8-9页

作者： christopher c.Udoye Rudolf A.Manz Institute for Systemic Inflammation Research University of LübeckLübeckGermany

In two recent studies published in Nature,Florsheim et *** Plum et *** that allergic-specific reactions induced by immunoglobulin(Ig)E mediated mast cell activation is crucial for the timely induction of antigen-avoidance behaviour.1,2 These studies prove the concept that allergic sensitization triggers the formation of avoidance behaviour and define the underlying molecular mechanism.

关键词： allergic mechanism

Improved hemostasis with major hepatic resection in the current surgical era

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Hepatobiliary & Pancreatic Diseases International 2019年第5期18卷 439-445页

作者： christopher W Mangieri Matthew A Strode Bradley c Bandera Department of Surgery Dwight D. Eisenhower Army Medical Center(DDEAMC)Fort GordonGA 30809USA Department of Surgical Oncology Roswell Park Cancer InstituteBuffaloNY 14203USA

Background: Major hepatic resection, predominantly performed for oncologic intent, is a complex procedure with the potential for severe intraoperative hemorrhage. The current surgical era has the ability to improve hemostasis throughout the performance of major hepatic resections which decreases blood transfusions and the detrimental effects associated with transfusion. We evaluated hemostasis and outcomes in the current surgical era of performing hepatic resections. Methods: Utilizing the American college of Surgeons (AcS) National Surgical Quality Improvement Program (NSQIP) database all major hepatic resections performed between 2012 and 2016 were analyzed in regards to hemostasis. Hemostasis was evaluated by the need for and magnitude of blood transfusions. Additional perioperative variables (including operative time, length of hospital stay, and mortality rates) were analyzed to assess for outcomes with hemostasis. The NSQIP results were compared to previous publications involving major hepatic resections to detect improvement in hemostasis and outcomes in the current surgical era. Results: A total of 22777 major hepatic resections met the inclusion criteria for analysis in the NSQIP database. An additional 21198 cases were compiled within the selected publications for comparative analysis. The transfusion rate in the current surgical era was 13.3% versus 38.7% in the previous era ( P = 0.0001). When a transfusion was required in the current surgical era there was a two-fold reduction in the number of units transfused (1.5 U vs. 3.8 U, P = 0.0001). Statistically significant improvements in operative time and length of hospital stay were presented within the current surgical era ( P = 0.0001). When a transfusion was required there was an increased relative risk score of 7 for mortality (4.9% vs. 0.7%, P = 0.0001), however, improvement in mortality rates did not reach statistical significance across surgical eras (1.3% vs. 4.0%, P = 0.0001). conclusions: The cond

关键词： Major hepatic resection Improved hemostasis Improved outcomes

Horseshoe crab behavior:Patterns and processes

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current Zoology 2010年第5期56卷 I0001-I0003页

作者： christopher c.c.abot Winsor H.Watson Ⅲ Plymouth State University University of New Hampshire

1 Introduction The Ameriean horseshoe erab Limulus PolyPhemus has long served as a souree of delight and insPiration to a broad eross-seetion of seientists-from naturalists to ***, for the last hundred years or so,new... 详细信息

关键词：行为马蹄科学家自然主义蟹

Rider Optimization Algorithm Based Optimal cloud Server Selection in E-Learning

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computer Systems Science & Engineering 2023年第2期44卷 1749-1762页

作者： R.Soundhara Raja Pandian c.christopher columbus Department of computer Science and Engineering PSN College of Engineering and TechnologyMelathediyoorTamil Nadu627152India

currently,e-learning is one of the most prevalent educational methods because of its need in today’s *** classrooms and web-based learning are becoming the new method of teaching *** students experience a lack of access to resources commonly the educational *** remote loca-tions,educational institutions face signiﬁcant challenges in accessing various web-based materials due to bandwidth and network infrastructure *** objective of this study is to demonstrate an optimization and queueing tech-nique for allocating optimal servers and slots for users to access cloud-based e-learning *** proposed method provides the optimization and queue-ing algorithm for multi-server and multi-city constraints and considers where to locate the best *** optimal server selection,the Rider Optimization Algo-rithm(ROA)is utilized.A performance analysis based on time,memory and delay was carried out for the proposed methodology in comparison with the exist-ing *** proposed Rider Optimization Algorithm is compared to Par-ticle Swarm Optimization(PSO),Genetic Algorithm(GA)and Fireﬂy Algorithm(FFA),the proposed method is more suitable and effective because the other three algorithms drop in local optima and are only suitable for small numbers of user *** the proposed method outweighs the conventional techniques by its enhanced performance over them.

关键词： Optimization queuing slot selection server selection rider optimization algorithm

Sensitivity of precipitation statistics to urban growth in a subtropical coastal megacity cluster

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Journal of Environmental Sciences 2017年第9期29卷 6-12页

作者： christopher claus Holst Johnny c.L.chan chi-Yung Tam School of Energy and Enuironment City Uniuersity of liong KongHong KongChina Guy carpenter Asia-Pacific climate Impact centre City Uniuersity of Hong KongHong KongChina Earth System Science Programme The Chinese Uniuersity of Hong KongHong KongChina

This short paper presents an investigation on how human activities may or may not affect precipitation based on numerical simulations of precipitation in a benchmark case with modified lower boundary conditions, representing different stages of urban development in the model. The results indicate that certain degrees of urbanization affect the likelihood of heavy precipitation significantly, while less urbanized or smaller cities are much less prone to these effects. Such a result can be explained based on our previous work where the sensitivity of precipitation statistics to surface anthropogenic heat sources lies in the generation of buoyancy and turbulence in the planetary boundary layer and dissipation through triggering of convection. Thus only mega cities of sufficient size, and hence human-activity-related anthropogenic heat emission, can expect to experience such effects. In other words, as cities grow, their effects upon precipitation appear to grow as well.

关键词： Urban precipitation Micro climate sensitivity Urbanization

The Incomprehensible Art of Thomas Hobbes

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Frontiers of Philosophy in china 2016年第4期11卷 680-697页

作者： christopher c. chrappa Department of Philosophy Huazhong University of Science and Technology Wuhan 430000 China

The political philosophy of Thomas Hobbes is one of the cornerstones of modern liberalism. Resting on controversial doctrines of freedom, perception, human nature, and history, the foundations of Hobbesianism presuppose an emergence of reason from matter-in-motion that Hobbes never adequately explains. In this paper I explore the motivations and consequences of his neglect of fundamental philosophical problems through a series of ambiguous uses of key terms manifested his work： nature, necessity, and God in metaphysics and theology; freedom in politics; intelligible unity in epistemology; and imagination in ethics. These show up, respectively, in his doctrines of naturalism, political science, phenomenalism, and the state of nature. While it may be that Hobbes＇s metaphysical ideas are finally incoherent, this only raises a further question： Might Hobbes have recognized that the goal of a liberal state-a common human war against death-can only be grounded on sketchy and inadequate metaphysics, to be suppressed and avoided so far as possible？ Primarily through a reading of the Leviathan, I explore this question and tentatively propose that an affirmative answer is warranted.

关键词： Hobbes Leviathan science political philosophy freedom state of nature

Quantized Redshift and its Significance for Recent Observation

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Research in Astronomy and Astrophysics 2024年第9期24卷 156-166页

作者： Arindam Mal Sarbani Palit christopher c.Fulton Sisir Roy Indian Space Research Organization Space Applications CentreAhmedabadIndia Indian Statistical Institute CVPR UnitKolkataIndia Protostar Inc.15652 Carrousel DriveCanyon CountryCA 91387USA National Institute of Advanced Studies IISC CampusBangaloreIndia

With the recent observational evidence in extragalactic astronomy,the interpretation of the nature of quasar redshift continues to be a research *** high redshifts are being detected for extragalactic objects that are presumably very distant and young while also exhibiting properties that are characteristic of a more mature galaxy such as *** to Halton Arp and Geoffrey Burbidge,redshift disparities consist of an intrinsic component and are related to an evolutionary *** observed redshift periodicity at integer multiples of0.089 in log scale and Burbidge observed redshift periodicity at integer multiples of 0.061 in linear *** Singular Value Decomposition based periodicity estimation is known to be superior for noisy data sets,especially when the data contain multiple harmonics and overtones,mainly irregular in nature,we have chosen it to be our primary tool for analysis of the quasar-galaxy pair redshift *** have observed a fundamental periodicity of0.051 with a confidence interval of 95%in linear scale with the site-available Sloan Digital Sky Survey Data Release 7(SDSS DR7)quasar-galaxy pair data *** have independently generated quasar-galaxy pair data sets from both 2d F and SDSS and found fundamental periodicities of 0.077 and 0.089,respectively,in log scale with a confidence interval of 95%.

关键词： galaxies:distances and redshifts (galaxies:)quasars:absorption lines cosmology:observations