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91.
Shu Ge Fukun Shi Guiyao Zhou Songhao Liu Zhiyun Hou Lu Peng 《Plasmonics (Norwell, Mass.)》2016,11(5):1307-1312
A surface plasmon resonance sensor based on a U-shaped photonic crystal fiber with a rectangular lattice has been designed through finite element method. The U-shaped fiber exhibits not only stronger mechanical strength but also better sensor performance than our previous scheme. The upper detection limit extends to higher analyze refractive index, 1.384, for phase interrogation. We introduce a ratio to evaluate the impact of higher order plasmonic mode. For wavelength modulation scheme, the parameter to describe the performance of a sensor is chosen to be the figure of merit, which can be up to 533.8[RIU?1] around complete coupling condition. 相似文献
92.
Gaëtan Podevijn Rehan O’Grady Nithin Mathews Audrey Gilles Carole Fantini-Hauwel Marco Dorigo 《Swarm Intelligence》2016,10(3):193-210
We study the psychophysiological state of humans when exposed to robot groups of varying sizes. In our experiments, 24 participants are exposed sequentially to groups of robots made up of 1, 3 and 24 robots. We measure both objective physiological metrics (skin conductance level and heart rate), and subjective self-reported metrics (from a psychological questionnaire). These measures allow us to analyse the psychophysiological state (stress, anxiety, happiness) of our participants. Our results show that the number of robots to which a human is exposed has a significant impact on the psychophysiological state of the human and that higher numbers of robots provoke a stronger response. 相似文献
93.
Cecilia Polacow Herzog 《Landscape and Ecological Engineering》2016,12(1):141-150
The city of Rio de Janeiro now covers what was formerly coastal Atlantic rainforest. Native biodiversity has been lost from most of the metropolitan area due to changes in land use, introduction of exotic species, and influence of foreign designs in public and private parks and gardens. This paper presents a multifunctional green infrastructure planning proposal to protect and regenerate native biodiversity in the last remaining natural ecosystem fragments in a watershed within the city’s limits. The proposal is based on social–ecological assessments and analyses. The watershed contains an extensive mangrove remnant surrounded by a protected massif partially covered by coastal Atlantic rainforest and is one of the very last productive landscapes where residents experience a strong sense of place. The strategy is to reconcile urban development with environmental achievements to conserve existing ecosystem patches, which will be connected by way of riparian corridors and other open spaces, such as streets, private yards and public areas, by using native species and ecological design. The green infrastructure framework is planned at the watershed scale. On a neighborhood and local scale, the plan is to promote public participation, develop new ecological aesthetics, encourage the planting of native species, and establish an innovative circulation system within a low-impact design framework to achieve various abiotic, biotic, and cultural goals. In addition to the economic benefits, accessible food production, rural tourism and ecotourism have the potential to unite people and nature within the city. 相似文献
94.
Herbert Budzikiewicz Mathias Schäfer Diana Uría Fernández Sandra Matthijs Pierre Cornelis 《Biometals》2007,20(2):135-144
Characteristic fragment ions of the various chromophores of the pyoverdin siderophore family obtained by collision activated
dissociation of the [M+2H]2+ ions are reported allowing unambiguous identification. Tandem mass spectrometrical studies revealed the existence of the
first example of a ferribactin with a succinamide side chain, and they add some information to the problem in which way a
malic acid side chain is attached to the chromophore. 相似文献
95.
Understanding how the environment impacts development is of central interest in developmental and evolutionary biology. On
the one hand, we would like to understand how the environment induces phenotypic changes (the study of phenotypic plasticity).
On the other hand, we may ask how a development system maintains a stable and precise phenotypic output despite the presence
of environmental variation. We study such developmental robustness to environmental variation using vulval cell fate patterning
in the nematode Caenorhabditis elegans as a study system. Here we review both mechanistic and evolutionary aspects of these studies, focusing on recently obtained
experimental results. First, we present evidence indicating that vulval formation is under stabilizing selection. Second,
we discusss quantitative data on the precision and variability in the output of the vulval developmental system in different
environments and different genetic backgrounds. Third, we illustrate how environmental and genetic variation modulate the
cellular and molecular processes underlying the formation of the vulva. Fourth, we discuss the evolutionary significance of
environmental sensitivity of this developmental system. 相似文献
96.
97.
Melissa A. Partridge Sumana Gopinath Simon J. Myers Jens R Coorssen 《Journal of chemical biology》2016,9(1):9-18
An initial proteomic analysis of the cuprizone mouse model to characterise the breadth of toxicity by assessing cortex, skeletal muscle, spleen and peripheral blood mononuclear cells. Cuprizone treated vs. control mice for an initial characterisation. Select tissues from each group were pooled, analysed in triplicate using two-dimensional gel electrophoresis (2DE) and deep imaging and altered protein species identified using liquid chromatography tandem mass spectrometry (LC/MS/MS). Forty-three proteins were found to be uniquely detectable or undetectable in the cuprizone treatment group across the tissues analysed. Protein species identified in the cortex may potentially be linked to axonal damage in this model, and those in the spleen and peripheral blood mononuclear cells to the minimal peripheral immune cell infiltration into the central nervous system during cuprizone mediated demyelination. Primary oligodendrocytosis has been observed in type III lesions in multiple sclerosis. However, the underlying mechanisms are poorly understood. Cuprizone treatment results in oligodendrocyte apoptosis and secondary demyelination. This initial analysis identified proteins likely related to axonal damage; these may link primary oligodendrocytosis and secondary axonal damage. Furthermore, this appears to be the first study of the cuprizone model to also identify alterations in the proteomes of skeletal muscle, spleen and peripheral blood mononuclear cells. Notably, protein disulphide isomerase was not detected in the cuprizone cohort; its absence has been linked to reduced major histocompatibility class I assembly and reduced antigen presentation. Overall, the results suggest that, like experimental autoimmune encephalomyelitis, results from the standard cuprizone model should be carefully considered relative to clinical multiple sclerosis. 相似文献
98.
99.
This paper explains the biophysical principles which, according to us, govern the Proteus mirabilis swarm phenomenon. Then, this explanation is translated into a mathematical model, essentially based on partial differential
equations. This model is then implemented using numerical methods of the finite volume type in order to make simulations.
The simulations show most of the characteristics which are observed in situ and in particular the terrace generation.
相似文献
100.
David C. Queller 《Biology & philosophy》2011,26(6):905-913
Biologists and philosophers differ on whether selection should be analyzed at the level of the gene or of the individual.
In Peter Godfrey-Smith’s book, Darwinian Populations and Natural Selection, he argues that individuals can be good members
of Darwinian populations, whereas genes rarely can. I take issue with parts of this view, and suggest that Godfrey-Smith’s
scheme for thinking about Darwinian populations is also applicable to populations of genes. 相似文献