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Nylon 6-cellulose composite hosted in a hypodermic needle: Biofluid extraction and analysis by ambient mass spectrometry in a single device

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Journal of Pharmaceutical Analysis 2023年第11期13卷 1346-1352页

作者： jaime Millan-Santiago Rafael Lucena Soledad Cardenas Affordable and Sustainable Sample Preparation(AS2P)Research Group Analytical Chemistry DepartmentChemical Institute for Energy and Environment(IQUEMA)University of CordobaE-14071CordobaSpain

This study proposes a hypodermic needle(HN)as a sorbent holder and an electrospray(ESI)emitter,thus combining extraction and analysis in a single device.A novel nylon 6-cellulose(N6-Cel)composite sorbent is proposed to extract methadone from oral fluid *** cellulosic substrate provides the composite with high porosity,permitting the flow-through of the sample,while the polyamide contributes to the extraction of the *** low price of the devices(considering the holder and the sorbent)contributes to the affordability of the method,and their small size allows easy transportation,opening the door to on-site *** the optimum conditions,the analyte can be determined by high-resolution ambient ionization mass spectrometry at a limit of detection(LOD)as low as 0.3 mg/L and precision(expressed as relative standard deviation,RSD)better than 9.3%.The trueness,expressed as relative recovery(RR),ranged from 90%to 109%.As high-resolution mass spectrometers are not available in many laboratories,the method was also adapted to low-resolution *** this sense,the direct infusion of the eluates in a triple quadrupole-mass spectrometry provided an LOD of 2.2 mg/*** RSD was better than 5.3%,and the RR ranged from 96%to 121%.

关键词： ESI emitter Mass spectrometry Hypodermic needle Composite Methadone

Abandoned corrals: colonization and vegetation recovery of ephemeral habitats in silvo-pastoral systems

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Journal of Plant Ecology 2020年第6期13卷 722-731页

作者： Arie Vinograd Eli Zaady jaime Kigel Institute of Plant Science and Genetics in Agriculture Robert H.Smith Faculty of AgricultureFood and EnvironmentHebrew University of JerusalemRehovot 76100Israel Department of Natural Resources Gilat Research CenterAROMobile Post Negev 85280Israel

Aims Management of silvo-pastoral systems in planted and natural forests in semi-arid Mediterranean regions often employs seasonal night corrals for animal *** management system changes the spatial distribution of animal excreta,resulting in a net transfer of soil mineral resources and their accumulation in the *** abandonment,corrals are colonized by ruderal species,becoming focal sources for their spread in the *** aimed to implement a rational management of seasonal sheep corrals based on a better understanding of the vegetation processes occurring in abandoned corrals,in order to alleviate their negative impact in the *** Relationships between temporal changes in the vegetation,the soil seed-bank and levels of soil nutrients were studied in a chronosequence of abandoned sheep corrals and compared with nearby reference plots in planted Eucalyptus forests grazed by sheep in the semi-arid North-Western Negev,*** region has a bi-seasonal Mediterranean climate,with high dominance of annual species in the grazing *** Findings Abandoned sheep corrals were colonized by seeds of ruderals originating in older abandoned *** successional changes occur at a slow rate,driven by the depletion of soil resources in the abandoned corrals,and were still in progress 20 years after *** were gradually replaced,first by taller grasses and followed by short grasses,but most forbs and particularly geophytes did not recover during this *** of the original herbaceous vegetation in the corrals was through seed dispersal from the surrounding vegetation,not from the original soil seed-bank remaining in the corrals after *** species in the grazed,planted forests behave as patch-tracking *** persistency depends on constant creation of new corrals compensating for the gradually dwindling populations in older abandoned corrals,and on the availability of dispersa

关键词： metapopulation ruderals seasonal grazing seed-bank sheep succession

GBP-WAHSN:A Group-Based Protocol for Large Wireless Ad Hoc and Sensor Networks

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Journal of Computer Science & Technology 2008年第3期23卷 461-480页

作者： jaime Lloret Miguel Garcia Jesus Tomás Fernando Boronat Department of Communications Polytechnic University of ValenciaCamino Vera s/n46022ValenciaSpain

Grouping nodes gives better performance to the whole network by diminishing the average network delay and avoiding unnecessary message forwarding and additional overhead. Many routing protocols for ad-hoc and sensor networks have been designed but none of them are based on groups. In this paper, we will start defining group-based topologies, and then we will show how some wireless ad hoc sensor networks （WAHSN） routing protocols perform when the nodes are arranged in groups. In our proposal connections between groups are established as a function of the proximity of the nodes and the neighbor＇s available capacity （based on the node＇s energy）. We describe the architecture proposal, the messages that are needed for the proper operation and its mathematical description. We have also simulated how much time is needed to propagate information between groups. Finally, we will show a comparison with other architectures.

关键词： group-based protocol group-based architecture group-based routing algorithm large networks

Slow light bimodal interferometry in onedimensional photonic crystal waveguides

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Light(Science & Applications) 2021年第2期10卷 154-165页

作者： Luis Torrijos-Morán Amadeu Griol jaime García-Rupérez Nanophotonics Technology Center Universitat Politècnica de Valencia46022 ValenciaSpain

Strongly influenced by the advances in the semiconductor industry,the miniaturization and integration of optical circuits into smaller devices has stimulated considerable research efforts in recent *** other structures,integrated interferometers play a prominent role in the development of photonic devices for on-chip applications ranging from optical communication networks to point-of-care analysis ***,it has been a longstanding challenge to design extremely short interferometer schemes,as long interaction lengths are typically required for a complete modulation *** approaches,including novel materials or sophisticated configurations,have been proposed to overcome some of these size limitations but at the expense of increasing fabrication complexity and ***,we demonstrate for the first time slow light bimodal interferometric behaviour in an integrated single-channel one-dimensional photonic *** proposed structure supports two electromagnetic modes of the same polarization that exhibit a large group velocity ***,an over 20-fold reduction in the higher-order-mode group velocity is experimentally shown on a straightforward all-dielectric bimodal structure,leading to a remarkable optical path reduction compared to other conventional ***,we experimentally demonstrate the significant performance improvement provided by the proposed bimodal photonic crystal interferometer in the creation of an ultra-compact optical modulator and a highly sensitive photonic sensor.

关键词： interferometer polarization modulator

Incipient sexual isolation in Laupala cerasina： Females discriminate population-level divergence in acoustic characters

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Current Zoology 2012年第3期58卷 416-425页

作者： jaime L. GRACE Kerry L. SHAW Department of Biology University of Maryland College Park MD 20742 USA Department of Neurobiology and Behavior Cornel1 University Ithaca NY 14853 USA kls4@cornell.edu

Sexual selection by female choice can shape the evolution of male traits within populations, since the most attractive males experience an increase in fitness through elevated mating success. Speciation by sexual selection occurs when evolution in traits and preferences within populations causes differentiation among populations, such that females in alternative populations prefer sexual signals of their own population relative to others. Differentiated traits and preferences thereby play an active role in limiting gene flow between divergent populations. The effectiveness of differentiated preferences in maintaining differentiated male signals against the homogenizing effects of gene flow across populations will be limited by both the degree to which fe- males can discriminate against non-local males, and the breeding values of traits and preferences. Populations of the Hawaiian cricket Laupala cerasina have diverged in pulse rate, a sexually selected male signal, and female acoustic preference for pulse rate. Gene flow between neighboring populations may be reduced if migrants from sexually diverged populations experience re- duced mating success. We show that females discriminate among divergent songs characteristic of neighboring populations, that differences among populations in song and preference breed true in a common environment, and that mean preferences for each population closely match the mean pulse rates. Divergence in preference was observed only between populations that also dif- fered in song. Along with a striking ability to discriminate slight differences in song, correlated evolution of song and preference within populations could be a mechanism that promotes assortative mating among populations, thereby reducing gene flow, and leading to speciation in Laupala [Current Zoology 58 （3）： 416-425, 2012].

关键词： Sexual selection Phenotypic divergence Behavioral isolation Preference functions Speciation

Modeling egg development of the pest Clavipalpus ursinus （Coleoptera： Melolonthidae） using a temperature-dependent approach

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Insect Science 2012年第6期19卷 657-665页

作者： Andrea Escobar Rodrigo Gil Carlos Ricardo Bojaca jaime Jimenez Facultad de Ciencias Naturales e Ingenieria Departamento de Ciencias Basicas Universidad de Bogota Jorge Tadeo Lozano Bogota Direccion Tecnica de Sanidad Vegetal Instituto Colombiano Agropecuario Bogota Colombia

Predicting the population dynamics of insects in natural conditions is es- sential for their management or preservation, and temperature-dependent development models contribute to achieving this. In this research the effects of temperature and soil moisture content on egg development and hatching of Clavipalpus ursinus （Blanchard） were evaluated. The eggs were exposed to seven temperature treatments with averages of 7.2, 13.0, 15.5, 19.7, 20.6, 22.0 and 25.3~C, in combination with three soil moisture contents of 40%, 60% and 80%. A linear and two non-linear （Lactin and Briere） models were evaluated in order to determine the thermal requirements of this developmental stage. Temperature affected significantly the time of development and egg hatching, while no significant effect was observed for moisture content. Thermal requirements were set as： 7.2℃ for lower developmental threshold, 20.6℃ for optimum developmental threshold, 25.3℃ for maximum temperature and 344.83 degree-days for the thermal constant. The linear model described satisfactorily egg development at intermediate temperatures; nev- ertheless, a slightly better fit of the observed data was obtained with the Lactin model. Egg development took place inside a narrow range of temperatures. Consequently, an increment of soil temperature could generate a negative impact on the population size of this species or changes in its biological parameters.

关键词： egg development pests soil moisture thermal requirements

Feeding on clean food?Potential effects of electric organ discharges by Torpedo spp.(Torpediniformes:Torpedinidae)on their trophically transmitted parasites

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Integrative Zoology 2022年第2期17卷 234-245页

作者： jaime PENADÉS-SUAY Tania REGACHO Francisco Javier AZNAR Marine Zoology Unit Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValènciaSpain LAMNA Association for the study of elasmobranchs from the Valencian Community ValènciaSpain

Members of the Torpedinidae(torpedoes)and Hypnidae(coffin ray)use electric organ discharges(EOD)to stun or kill their prey before *** investigated whether EOD could also negatively affect the helminth larvae infecting these preys through a surrogate model:we applied electric discharges to individuals of blue whiting,Micromesistius poutassou,that harbored live larvae of *** mortality throughout a 6-h period was significantly higher in the treatment group,suggesting that EODs could significantly hamper helminth *** then tested whether torpedinids and hypnids(“strong-EOD”families)harbored species-poor helminth(cestode)assemblages compared with“weak-EOD”Torpediniformes(Narcidae and Narkidae)and other *** on comparisons on estimated species diversity and mean species richness of tapeworms at host individual level we found that(i)Torpediniformes had the lowest tapeworm diversity of all Batoidea orders;(ii)Torpedo *** had the lowest mean cestode richness at host individual level,and this could not be related to other host factors influencing cestode diversity in chondrichthyans,that is body size,trophic level or dietary ***,a preliminary comparison between“strong-EOD”and“weak-EOD”Torpediniformes did not detect clear differences of cestode ***,evidence supporting an unambiguous contribution of EODs to depauperate cestode assemblages requires further research.

关键词： Anisakis Batoidea cestode EOD behavior Torpediniform Torpedo

A species-transport model for circulation in a leading-edge vortex

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Advances in Aerodynamics 2022年第1期4卷 762-779页

作者： Clara Giner-Morency jaime G.Wong Department of Mechanical Engineering University of AlbertaEdmontonT6G 1H9Canada

In this study,we propose a model to predict circulation growth along the span of a rotating wing,in which circulation transport is represented as species *** particles entering the vortex shear layer at the leading edge are initialized as vorticity-containing mass and are advected by the flow along the span.A circulation budget is presented,consisting of a generation and transport term,the latter derived from the vorticity transport equation,which leaves only two unknowns for the modeller to determine:the shear-layer thickness and the spanwise flow *** find that the model is insensitive to the value chosen for the shear-layer thickness,as varying the thickness by an order of magnitude only changes the output by a few ***,we use Bernoulli equation in a rotating coordinates system as a basic model for spanwise *** verify the accuracy of the model,the predicted circulation values are compared against experimental circulation values and show good agreement to measurements close to the axis of rotation,which corresponds to the spanwise locations at which the spanwise flow model best matches experimental *** is suggested,therefore,that this model produces accurate results subject to an appropriate spanwise flow model.

关键词： Leading-edge vortices Circulation transport Vortex growth Rotating wings

A re-evaluation of the average chain length of lacustrine sedimentary n-alkanes as a paleoproxy on the Qinghai-Tibet Plateau

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Frontiers of Earth Science 2023年第4期17卷 905-919页

作者： Mingda WANG Qin LI jaime TONEY David HENDERSON Juzhi HOU School of Geography Liaoning Normal UniversityDalian 116029China Alpine Paleoecology and Human Adaptation(ALPHA)Group State Key Laboratory of Tibetan Plateau Earth SystemResources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China School of Geographical and Earth Sciences University of GlasgowGlasgow G128QQScotlandUK CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China

Long-chain n-alkanes are one of the most common organic compounds in terrestrial plants and they are well-preserved in various geological archives.n-alkanes are relatively resistant to degradation and thus they can provide high-fidelity records of past vegetation and climate ***,previous studies have shown that the interpretation of n-alkane proxies,such as the average chain length(ACL),is often ambiguous since this proxy depends on more than one *** vegetation and climate could exert controls on the n-alkane ACL,and hence its interpretation requires careful consideration,especially in regions like the Qinghai-Tibet Plateau(QTP)where topography,biome type and moisture source are highly *** further evaluate the influences of vegetation and climate on the ACL in high-elevation lakes,we examined the n-alkane distributions of the surface sediments of 55 lakes across the *** results show that the ACL across a climatic gradient is significantly affected by precipitation,rather than by *** positive correlation between ACL and precipitation may be because of the effect of microbial degradation during ***,we suggest that more caution is needed in the interpretation of ACL data in different regions.

关键词： ACL average chain length n-alkanes leaf wax lake sediments Qinghai-Tibet Plateau