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111.
Responses of fig wasps to host plant volatile cues 总被引:4,自引:0,他引:4
Fig wasps (Chalcidoidea; Agaonidae) are intimately associated with the 750 or so species of fig trees (Ficus, Moraceae). Each tree species is usually pollinated by a single species of wasp belonging to the subfamily Agaoninae, while other wasps of the family are parasitoids or seed predators. Previous experiments have shown that the wasps are attracted to the trees by volatiles emanating from the figs. Using fig-bearing trees and arrays of sticky traps baited with figs, we investigated the specificity of wasp attraction and its timing. The pollinators of two closely relatedFicus species were specifically attracted to figs of their host species and only at the time when figs were ready to be pollinated. Some nonpollinating fig wasps appear to respond to the same volatile cues. 相似文献
112.
Masao Tomikawa Frank W. Harris Stephen Z. D. Cheng Edward Galentier 《Reactive and Functional Polymers》1996,30(1-3):101-107
A series of new, substituted pyromellitic dianhydrides were synthesized from 1,2,4,5-tetramethylbenzene. New soluble rigid-rod polyimides were obtained from the dianhydrides and 2,2′-bis(trifluoromethyl)-4,4′-biphenyl (PFMB) in phenolic solvents in the presence of isoquinoline as a catalyst. The polyimides are soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), m-cresol and other solvents, in spite of having no bending in their rigid structures.
UV irradiation changed color of the polyimide solutions and also their viscosity. We observed new absorbance in the 700-nm region and an ESR signal by UV irradiation. The new visible absorbance and the ESR signal are derived from the same origin. They are attributed to the anion radical of the diimide moiety in the polyimide as deduced from the hyper fine structure of the ESR signal. In addition, UV irradiation diminishes the solution viscosity. 相似文献
113.
Mount Emily Gaultney Daniel Vrijsen Geert Adams Michael Baek So-Young Hudek Kai Isabella Louis Crain Stephen van Rynbach Andre Maunz Peter Kim Jungsang 《Quantum Information Processing》2016,15(12):5281-5298
Quantum Information Processing - Many of the challenges of scaling quantum computer hardware lie at the interface between the qubits and the classical control signals used to manipulate them.... 相似文献
114.
In this paper, we introduce new methods for finding functions that lower bound the value function of a stochastic control problem, using an iterated form of the Bellman inequality. Our method is based on solving linear or semidefinite programs, and produces both a bound on the optimal objective, as well as a suboptimal policy that appears to works very well. These results extend and improve bounds obtained in a previous paper using a single Bellman inequality condition. We describe the methods in a general setting and show how they can be applied in specific cases including the finite state case, constrained linear quadratic control, switched affine control, and multi‐period portfolio investment. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
115.
Stephen Abell Nhan Do 《International Journal of Parallel, Emergent and Distributed Systems》2016,31(5):450-468
This article presents a GPU-based single-unit deadlock detection methodology and its algorithm, GPU-OSDDA. Our GPU-based design utilizes parallel hardware of GPU to perform computations and thus is able to overcome the major limitation of prior hardware-based approaches by having the capability of handling thousands of processes and resources, whilst achieving real-world run-times. By utilizing a bit-vector technique for storing algorithm matrices and designing novel, efficient algorithmic methods, we not only reduce memory usage dramatically but also achieve two orders of magnitude speedup over CPU equivalents. Additionally, GPU-OSDDA acts as an interactive service to the CPU, because all of the aforementioned computations and matrix management techniques take place on the GPU, requiring minimal interaction with the CPU. GPU-OSDDA is implemented on three GPU cards: Tesla C2050, Tesla K20c, and Titan X. Our design shows overall speedups of 6-595X over CPU equivalents. 相似文献
116.
117.
Bahador Saket Carlos Scheidegger Stephen G. Kobourov Katy Börner 《Computer Graphics Forum》2015,34(3):441-450
We investigate the memorability of data represented in two different visualization designs. In contrast to recent studies that examine which types of visual information make visualizations memorable, we examine the effect of different visualizations on time and accuracy of recall of the displayed data, minutes and days after interaction with the visualizations. In particular, we describe the results of an evaluation comparing the memorability of two different visualizations of the same relational data: node‐link diagrams and map‐based visualization. We find significant differences in the accuracy of the tasks performed, and these differences persist days after the original exposure to the visualizations. Specifically, participants in the study recalled the data better when exposed to map‐based visualizations as opposed to node‐link diagrams. We discuss the scope of the study and its limitations, possible implications, and future directions. 相似文献
118.
Clarke DT Botchway SW Coles BC Needham SR Roberts SK Rolfe DJ Tynan CJ Ward AD Webb SE Yadav R Zanetti-Domingues L Martin-Fernandez ML 《The Review of scientific instruments》2011,82(9):093705
Optics clustered to output unique solutions (OCTOPUS) is a microscopy platform that combines single molecule and ensemble imaging methodologies. A novel aspect of OCTOPUS is its laser excitation system, which consists of a central core of interlocked continuous wave and pulsed laser sources, launched into optical fibres and linked via laser combiners. Fibres are plugged into wall-mounted patch panels that reach microscopy end-stations in adjacent rooms. This allows multiple tailor-made combinations of laser colours and time characteristics to be shared by different end-stations minimising the need for laser duplications. This setup brings significant benefits in terms of cost effectiveness, ease of operation, and user safety. The modular nature of OCTOPUS also facilitates the addition of new techniques as required, allowing the use of existing lasers in new microscopes while retaining the ability to run the established parts of the facility. To date, techniques interlinked are multi-photon/multicolour confocal fluorescence lifetime imaging for several modalities of fluorescence resonance energy transfer (FRET) and time-resolved anisotropy, total internal reflection fluorescence, single molecule imaging of single pair FRET, single molecule fluorescence polarisation, particle tracking, and optical tweezers. Here, we use a well-studied system, the epidermal growth factor receptor network, to illustrate how OCTOPUS can aid in the investigation of complex biological phenomena. 相似文献
119.
Kevin Curran Michelle Murray David Stephen Norrby Martin Christian 《New Review of Information Networking》2013,18(1-2):47-59
Libraries, as we know them today, can be defined by the term Library 1.0. This defines the way resources are kept on shelves or at a computer behind a login. These resources can be taken from a shelf, checked out by the library staff, taken home for a certain length of time and absorbed, and then returned to the library for someone else to avail of. Library 1.0 is a one-directional service that takes people to the information they require. Library 2.0 – or L2 as it is now more commonly addressed as – aims to take the information to the people by bringing the library service to the Internet and getting the users more involved by encouraging feedback participation. This paper presents an overview of Library 2.0 and introduces web 2.0 concepts. 相似文献
120.
Stephen C. Riley Jacques Rinchard Mark P. Ebener Donald E. Tillitt Kelly R. Munkittrick Joanne L. Parrott Jeffrey D. Allen 《Journal of Great Lakes research》2011,37(4):732-737
Thiamine deficiency is responsible for reproductive impairment in several species of salmonines in the Great lakes, and is thought to be caused by the consumption of prey containing thiaminase, a thiamine-degrading enzyme. Because thiaminase levels are extremely high in dreissenid mussels, fish that prey on them may be susceptible to thiamine deficiency. We determined thiamine concentrations in lake whitefish Coregonus clupeaformis eggs from the upper Laurentian Great Lakes to assess the potential for thiamine deficiency and to determine if thiamine concentrations in lake whitefish eggs were related to maternal diet. Mean thiamine concentrations in lake whitefish eggs were highest in Lake Huron, intermediate in Lake Superior, and lowest in Lake Michigan. Some fish had thiamine concentrations below putative thresholds for lethal and sublethal effects in salmonines, suggesting that some larval lake whitefish may currently be at risk of at least sublethal effects of low thiamine concentrations, although thiamine thresholds are unknown for lake whitefish. Egg thiamine concentrations in lake whitefish eggs were statistically significantly related to isotopic carbon signatures, suggesting that egg thiamine levels were related to maternal diet, but low egg thiamine concentrations did not appear to be associated with a diet of dreissenids. Egg thiamine concentrations were not statistically significantly related to multifunction oxidase induction, suggesting that lower egg thiamine concentrations in lake whitefish were not related to contaminant exposure. 相似文献