检索结果-南通市图书馆

Twists and Gromov hyperbolicity of Riemann Surfaces

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2011年第1期27卷 29-44页

作者： Katsuhiko MATSUZAKI Jose M. rodriguez Department of Mathematics School of Education Waseda University Shinjuku Tokyo 169-8050 Japan Departamento de Matemdticas Universidad Carlos IH de Madrid Avenida de la Universidad 30 28911 Legangs Madrid Spain

The main aim of this paper is to study whether the Gromov hyperbolicity is preserved under some transformations on Riemann surfaces （with their Poincare metrics）. We prove that quasiconformal maps between Riemann surfaces preserve hyperbolicity; however, we also show that arbitrary twists along simple closed geodesics do not preserve it, in general.

关键词： Quasiconformal maps Riemann surfaces Gromov hyperbolicity

EBSD Investigation on Effect of Cooling Rate on Microstructure and Transformation Textures of high Strength hot-rolled Steel Plates

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2016年第3期23卷 261-269页

作者： Nancy M.LOPEZ GRANADOS Armando SALINAS rodriguez Department of Metallurgical Engineering and Materials Science Center of Research and Advanced StudiesCINVESTAV-Unidad Saltillo

The effect of cooling rate on the microstructure and transformation textures of high strength hot-rolled steels was *** treated samples subjected to different cooling conditions were characterized by optical and scanning electron microscopes using orientation imaging microscopy（OIM）.The experimental results demonstrate that there is a significant effect of cooling rate on microstructures and textures resulting from phase *** cooling rates lead to the appearance of the cube（001）[010],rotated cube（001）[110]/（001）[110],Goss（110）[001]and rotated Goss（110）[110]*** contrast,textures developed at rapid cooling rates are preferably of Cu（112）[111],Br（110）[112],transformed Cu（113）[110]and transformed Br（332）[113]/（112）[131].These texture changes are attributed to the selective character of the phase *** OIM technique was used to have a better understanding of the formation of phases and their relationship between microstructure and processing *** volume fraction of micro-constituents resulting from phase transformation such as bainite,martensite and different types of ferrite,can be measured satisfactorily by this technique correlating image quality of EBSD patterns to specific phases.

关键词： orientation imaging microscopy texture phase transformation microstructure steel

Abscisic Acid Catabolism Generates Phaseic Acid, a Molecule Able to Activate a Subset of ABA Receptors

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2016年第11期9卷 1448-1450页

作者： Pedro L. rodriguez Instituto de Biotogia Molecular y Celular de Plantas Consejo Superior de Investigaciones Cientificas-Universidad Politecnica de Valencia 46022 Valencia Spain

Abscisic acid （ABA） catabolic pathways are conventionally thought of as routes for ABA inactivation and, thus, reduction of the well-known ABA responses to cope with stress. however, this point of view was challenged by the finding that some forms of hydroxylated ABA generated by ABA catabolism still maintain biological activity （Zou et al., 1995; Kepka et al., 2011）.

关键词： MICROSPORE-DERIVED EMBRYOS (+)-ABSCISIC ACID 8'-hYDROXYLASE METABOLITES NAPUS

Generating native user interfaces for multiple devices by means of model transformation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2015年第12期16卷 995-1017页

作者： Ignacio MARIN Francisco ORTIN German PEDROSA Javier rodriguez Department of Research and Development CTIC Foundation Department of Computer Science University of Oviedo

In the last years, the types of devices used to access information systems have notably increased using different operating systems, screen sizes, interaction mechanisms, and software features. This device fragmentation is an important issue to tackle when developing native mobile service front-end applications. To address this issue,we propose the generation of native user interfaces(UIs) by means of model transformations, following the modelbased user interface(MBUI) paradigm. The resulting MBUI framework, called LIZARD, generates applications for multiple target platforms. LIZARD allows the definition of applications at a high level of abstraction, and applies model transformations to generate the target native UI considering the specific features of target platforms. The generated applications follow the UI design guidelines and the architectural and design patterns specified by the corresponding operating system manufacturer. The objective is not to generate generic applications following the lowest-common-denominator approach, but to follow the particular guidelines specified for each target device. We present an example application modeled in LIZARD, generating different UIs for Windows Phone and two types of Android devices(smartphones and tablets).

关键词： Model-to-model transformation Native user interfaces Model-based user interfaces Model-driven engineering

Sex and stress modulate pupal defense response in tobacco hornworm

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2023年第5期69卷 592-599页

作者： Sukhman Singh Sakshi Watts Ishveen Kaur Isabella rodriguez Jessica Ayala Dariela rodriguez Elian Martin Rupesh Kariyat Department of Entomology The Pennsylvania State UniversityState CollegePA 16802USA Department of Biology The University of Texas Rio Grande ValleyEdinburgTX 78539USA School of Earth Environmental and Marine Sciences The University of Texas Rio Grande ValleyEdinburgTX 78539USA Department of Entomology and Plant Pathology University of ArkansasFayettevilleAR 72701USA

In insects,larval and adult defenses against predators have been well ***,pupal(also known as resting stage)defenses have been overlooked and not examined *** some pupa possess antipredator strategies such as hairs,spines,cryptic coloration,and exudation of chemicals,few studies have tested these responses and the factors affecting ***,we investigated the behavioral responses in tobacco hornworm Manduca sexta that pupates in soil by introducing an external stimulus using vibrations from an electric toothbrush to mimic *** observed that *** made violent wriggling(twitching),followed by pulsating movements in response to the vibrational *** examination showed that these twitches and pulsating events occurred more frequently and for longer periods of time in male pupa and were dependent on the magnitude of the stress(high and low frequency).however,when we estimated the angular force exerted by pupa using radian and angular momentum of twitches,it was found to be independent of pupal sex.A follow-up experiment on possible cascading effects of stress exposure on eclosion success revealed that low-and high-frequency stress exposure didn’t cause any of the common defects in eclosed *** study clearly demonstrates that the so-called defenseless pupal stage uses a wide range of measurable defense behaviors that can actively defend against predators and should be examined further-linking observed behavior with underlying mechanisms.

关键词： hornworm predation pupal defenses pupal sex twitching

A UNIFIED APPROACh TO CERTAIN PROBLEMS OF BEST LOCAL APPROXIMATION

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Analysis in Theory and Applications 2007年第2期23卷 162-170页

作者： h. h. Cuenya M. D. Lorenzo C. N. rodriguez Universidad Nacional de Rio Cuarto Argentina

In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several *** approach extends and unifies several problems concern... 详细信息

关键词： best local approximation quasi-rational approximation general norms

Gone with the wind： Seasonal trends in foraging movement directions for a central-place forager

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2014年第5期60卷 604-615页

作者： Jesus hERNANDEZ-PLIEGO Carlos rodriguez Javier BUSTAMANTE Department of Wetland Ecology Estacion Biologica de Dofiana CSIC c/Amorico Vespucio s/n 41092 Seville Spain Department of Conservation Biology Estacion Biologica de Dofiana C SIC c/Amorico Vespucio s/n 41092 Seville Spain

Lesser kestrels Falco naumanni are migratory central-place foragers that breed in dynamic arable landscapes. After arriving from migration, kestrels have no knowledge of the distribution of crops, and consequently prey, around their colony. The energy demand of pairs increases as breeding season progresses, but at the same time prey abundance, and their knowledge on prey distribution, also increases. Wind can have a strong influence on flight cost and kestrels should try to reduce energy expendi- ture when possible. When prey abundance is low, kestrels have little knowledge of prey distribution, and pairs have no chicks, they could reduce foraging flight cost by leaving the colony with tailwinds. When prey is abundant, knowledge on prey distribu- tion has increased, and chick demand is high, kestrels should fly to the most favorable foraging patches. We analyzed foraging trips directions in a lesser kestrel colony along the breeding season and in relation to wind speed and direction. We recorded 664 foraging trips from 19 individuals using GPS-dataloggers. We found that outward flights direction changed from uniform to a concentrated distribution along the season, as prey abundance and individual experience increased. We also found a temporal trend in the angular difference between outward flights and wind directions, with low values early in the season and then increa- sing as expected, but again low values at the end, contrary to expectation. Results suggest changes in kestrels foraging strategy along the season in relation to wind. Kestrels depart more with tailwinds in exploratory flights early in the season, while there is a spurious coincidence in direction to preferred foraging patches and dominant wind direction at the end [Current Zoology 60 （5）： 604-615, 2014].

关键词： Falco naumanni Movement ecology Foraging behavior Wind effect GPS-dataloggers

Intrasexual competition enhances reproductive isolation between locally adapted populations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2018年第1期64卷 125-133页

作者： David BIERBACh Lenin ARIAS-rodriguez Martin PLATh Department of Biology and Ecology of Fishes Leibniz-lnstitute of Freshwater Ecology and Inland Fisheries Muggelseedamm 310 12587 Berlin Germany Division Academica de Ciencias Biologicas Universidad Juarez Autonoma de Tabasco (UJAT) 86150 Villahermosa Tabasco Mexico College of Animal Science and Technology Northwest A&F University Yangling Shaanxi 712100 China

During adaptation to different habitat types, both morphological and behavioral traits can undergo divergent selection. Males often fight for status in dominance hierarchies and rank positions predict reproductive success. Ecotypes with reduced fighting abilities should have low reproductive success when migrating into habitats that harbor ecotypes with superior fighting abilities. Livebearing fishes in the Poecilia mexicana-species complex inhabit not only regular freshwater environments, but also independently colonized sulfidic （h2S-containing） habitats in three river drainages. In the current study, we found fighting intensities in staged contests to be considerably lower in some but not all sulfidic surface ecotypes and the sulfidic cave ecotype compared with populations from non-sulfidic surface sites. This is perhaps due to selection imposed by h2S, which hampers oxygen uptake and transport, as well as cellular respiration. Furthermore, migrants from sulfidic habitats may lose fights even if they do not show overall reduced aggressiveness, as phys- iological performance is likely to be challenged in the non-sulfidic environment to which they are not adapted. To test this hypothesis, we simulated migration of h2S-adapted males into h2S-free waters, as well as h2S-adapted cave-dwelling males into sulfidic surface waters. We found that intruders established dominance less often than resident males, independent of whether or not they showed reduced aggressiveness overall. Our study shows that divergent evolution of male aggressive behavior may also contribute to the maintenance of genetic differentiation in this system and we call for more careful evaluation of male fighting abilities in studies on ecological speciation.

关键词： ecological speciation extremophile teleost local adaptation Poecilia premating isolation selection againstmigrants.

Plant geranylgeranyl diphosphate synthases: every (gene) family has a story

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

aBIOTECh 2021年第3期2卷 289-298页

作者： M.Victoria Barja Manuel rodriguez-Concepcion Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAB-UB Campus UAB Bellaterra08193 Barce-lonaSpain Institute for Plant Molecular and Cell Biology(BMCP) CSIC-Universitat Politecnica de Valencia46022 ValenciaSpain

Plant isoprenoids(also known as terpenes or terpenoids)are a wide family of primary and secondary metabolites with multiple *** particular,most photosynthesis-related isoprenoids(including carotenoids and chlorophylls)as well as diterpenes and polyterpenes derive from geranylgeranyl diphosphate(GGPP)produced by GGPP synthase(GGPPS)enzymes in several cell *** genomes typically harbor multiple copies of differentially expressed genes encoding GGPPS-like *** sequence comparisons allow to identify potential GGPPS candidates,experimental evidence is required to ascertain their enzymatic activity and biologi cal ***,functional analyses of the full set of potential GGPPS paralogs are only available for a handful of plant *** we review our current knowledge on the GGPPS families of the model plant Arabidopsis thaliana and the crop species rice(0ryza sativa),pepper(Capsicum annuum)and tomato(Solanum lycopersicum).The results indicate that a major determinant of the biological role of particular GGPPS paralogs is the expression profile of the corresponding genes even though specific interactions with other proteins(including GGPP-consuming enzymes)might also contribute to *** some species,however,a single GGPPS isoforms appears to be responsible for the production of most if not all GGPP required for cell *** the mechanisms regulating GGPPS activity in particular cell compartments,tissues,organs and plant species will be very useful for future metabolic engineering approaches aimed to manipulate the accumulation of particular GGPP-derived products of interest without negatively impacting the levels of other isoprenoids required to sustain essential cell functions.

关键词： Geranylgeranyl diphosphate GGPP GGPP synthase Isoprenoid Isoprenyl transferase