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Female mating status affects male mating tactic expression in the wolf spider rabidosa punctulata

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Current Zoology 2022年第1期68卷 121-127页

作者： Sophie BUNCH Dustin j.WILGErS Department of Natural Sciences McPherson College1600 E.EuclidMcPhersonKS 67460USA

Males and females have conflicting interests on the frequency and outcomes of mating *** maximize their fitness by mating with as many females as possible,whereas choosy females often reduce receptivity following *** male mating tactics can be adaptive in their expression to a variety of mating contexts,including interactions with a relatively unreceptive mated *** rabidosa punctulata wolf spiders can adopt distinctive mating tactics when interacting with a female,a complex courtship display,and/or a more coercive direct mount tactic that often involves grappling with females for *** this study,we set up female mating treatments with initial trials and then paired mated and unmated females with males to observe both female remating frequencies and the male mating tactics used during the *** adopted different mating tactics depending on the mating status of the female they were paired *** were more likely to adopt a direct mount tactic with already-mated females and courtship with unmated ***-mated females were considerably less receptive to males during experimental trials,although they did remate 34%of the time,the majority of which were with males using a direct mount *** males adjusting to these contextual cues were able to gain more copulations,the observation of multiple mating in female *** introduces the potential for sperm *** discuss this sexual conflict in terms of the fitness consequences of these mating outcomes for both males and females.

关键词： alternative mating tactic female multiple mating Lycosidae sexual conflict

Extracellular vesicles and angiotensin-converting enzyme 2 in COVID-19 disease

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BIOCELL 2024年第1期48卷 1-8页

作者： YU LIU rOBErT j.KASPEr NATALIE j.S.CHOI Department of Family and Community Medicine Northwestern University Feinberg School of MedicineChicagoIllinois

Extracellular vesicles(EVs)are membranous vesicular structures released from almost all eukaryotic cell types under different physiological or pathological *** evidence demonstrates that EVs can serve as mediators of intercellular communication between donor and recipient cells or microorganism-infected and noninfected *** disease 2019(COVID-19)disease is caused by infection of the severe acute respiratory syndrome coronavirus 2(SArS-CoV-2)of host cells in the respiratory system and various extra-pulmonary tissue/organs,resulting in complications of multiple organ *** the cell surface receptor,angiotensin-converting enzyme 2(ACE2)mediates cellular entry of SArS-CoV-2 into the host cells in patients with *** studies have found that ACE2 can be released with EVs,which have been shown to interfere with the entry of the virus into host cells and thus may be involved in COVID-19 *** addition,ACE2,neprilysin(NEP),and thimet oligopeptidase(TOP)are the key enzymes that regulate angiotensin metabolism by converting angiotensin II or angiotensin I to angiotensin 1-7,the latter of which has protective effects in counterbalancing the harmful effects of angiotensin II in COVID-19 *** review summarizes the recent research progress regarding EV-associated ACE2,NEP,and TOP and the perspectives of their potential involvement in the pathophysiology of COVID-19 disease.

关键词： Extracellular vesicles COVID-19 Angiotensin converting enzyme 2 Thimet oligopeptidase

Density and carrying capacity in the forgotten tigerland:Tigers in the understudied Nepalese Churia

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Integrative Zoology 2017年第3期12卷 211-227页

作者： Kanchan THAPA Marcella j.KELLY Department of Fish and Wildlife Conservation Virginia TechBlacksburgVirginiaUSA Conservation Science Unit WWF NepalBaluwatarKathmanduNepal

While there are numerous wildlife ecology studies in lowland areas of Nepal,there are no in-depth studies of the hilly Churia habitat even though it comprises 7642 km2 of potential wildlife habitat across the Terai *** investigated tiger,leopard and prey densities across this understudied *** camera trapping survey covered 536 km2 of Churia and surrounding areas within Chitwan National Park(CNP).We used 161 trapping locations and accumulated 2097 trap-nights in a 60-day survey period during the winter season of *** addition,we walked 136 km over 81 different line transects using distance sampling to estimate prey *** photographed 31 individual tigers,28 individual leopards and 25 other mammalian *** capture-recapture methods resulted in lower density estimates for tigers,ranging from 2.3 to 2.9 tigers per 100 km2,than for leopards,which ranged from 3.3 to 5.1 leopards per 100 *** addition,leopard densities were higher in the core of the Churia compared to surrounding *** estimated 62.7 prey animals per 100 km2 with forest ungulate prey(sambar,chital,barking deer and wild pig),accounting for 47%of the *** on prey availability,Churia habitat within CNP could potentially support 5.86 tigers per 100 km2 but our density estimates were lower,perhaps indicating that the tiger population is below carrying *** results demonstrate that Churia habitat should not be ignored in conservation initiatives,but rather management efforts should focus on reducing human disturbance to support higher predator numbers.

关键词： camera trapping carrying capacity churia habitat Panthera tigris tigris spatially explicit capture recapture

Geographic variation in sexual selection and implications for speciation in the Barn Swallow

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Chinese Birds 2015年第1期5卷 30-42页

作者： Elizabeth SC Scordato rebecca j Safran Department of Ecology and Evolutionary Biology The University of Colorado

Barn Swallows(Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with human settlements.A tractable species for both individual-based and population-level studies, Barn Swallows are a prominent model system in evolutionary, ecological, and behavioral research. Here we review work on sexual selection and population divergence in this species complex, focusing on comparative studies among populations and *** summarize variation in the targets of mate choice and in the information conveyed by sexually selected traits, and conclude that the benefits advertised by different traits may vary geographically. Finally, we consider the role of sexual selection as a driver of population divergence in this widespread and phenotypically variable species complex.

关键词： Barn Swallow Geographic variation Natural selection Sexual selection Speciation Tail streamers Ventral color

Luminescence properties of sol-gel derived silica gels doped and undoped with rE-complexes(rE=Eu,Tb)

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Chinese journal of Chemistry 1997年第4期15卷 327-335页

作者： Lin, j Li, B Zhang, Hj CHINESE ACAD SCI CHANGCHUN INST APPL CHEMRARE EARTH CHEM & PHYS LABCHANGCHUN 130022PEOPLES R CHINA

The luminescence properties of silica gels and silica gels doped with two rare earth complexes, Eu(TTA)(3) and Tb(o-CBA)(3) (TTA=thenoyltriffuocetate, o-CBA=o-chlorobenzoic acid) are reported and discussed. Pure silica gels show a blue luminescence, and the maximum excitation and emission wavelengths depend strongly on the solvents used. Both of the studied rare earth complexes exhibit the characteristic emissions of the rare earth ions in silica gels, i.e., Eu3+5D0-->F-7(j)(j=0,1,2,3,4), Tb3+5D4-->F-7(j)(j=3,4,5,6) transitions. Compared with the pure rE-complexes powder, the silica gels doped with rE-complexes show fewer emission lines of the rare earth ions. Furthermore the rare earth ion (Tb3+) presents a longer lifetime (1346 mu s) in silica gel doped with Tb(o-CBA)3 than in pure Tb((o-CBA)(3) powder (744 mu s). The reasons responsible for these results are discussed in the context.

关键词： sol-gel method luminescence silica gel rare earth complexes

Divergent foraging behavior in a hybrid zone： Darwin＇s tree finches （Camarhynchus spp.） on Floreana Island

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Current Zoology 2015年第1期61卷 181-190页

作者： Katharina j. PETErS Sonia KLEINDOrFEr School of Biological Sciences Flinders University GPO Box 2100 Adelaide 5001 Australia

Hybrid speciation is increasingly recognized as a mechanism for novel evolutionary trajectories. However, we know very little about the ecology of a contact zone that has arisen in sympatry. This study examines the foraging behavior and fitness of two species of Darwin＇s tree finches （Camarhynchus parvulus, C pauper） and hybrid offspring on Floreana Island. Previous study showed that the percentage of hybrids in the tree finch population increased from 19% in 2005 to 41% in 2010, and their body and beak size increased by -5% （parental phenotype did not change）. In 2005-2006, all three tree finch groups （two paren- tal species and hybrid birds） used the same foraging substrate, technique, and height. By 2010-2013, the small tree finch C. par- vulus had changed its foraging technique and the medium tree finch C. pauper had changed its foraging height. Both parental species had higher body condition when foraging at （divergent） mean foraging heights per species but hybrid birds did not. We discuss the implications of conserving forest to facilitate vertical niche expansion and the role of hybridization for genetic persis- tence [Current Zoology 61 （1）： 181-190, 2015].

关键词： Hybridization Speciation Adaptive radiation Conservation Scalesia Ecological niche

Identification of boundary surfaces in flows

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Applied Mathematics and Mechanics(English Edition) 2010年第9期31卷 1097-1104页

作者： B.HErrErA j.PALLArES Department d'Enginyeria Informàtica i Matematiques Universitat Rovira i VirgiliAvinguda Pasos Catalans 26Tarragona 43007Spain Department d'Enginyeria Mecànica Universitat Rovira i VirgiliAvinguda Pasos Catalans 26Tarragona 43007Spain

In this study, boundary surfaces of a flow field are defined as stream surfaces, on which the shear rates vanish, and a procedure is proposed to find them. The method, based on calculations using the velocity vector f... 详细信息

关键词： interracial surfaces structure of flow kinematics

Convergence and exact solutions of spline finite strip method using unitary transformation approach

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Applied Mathematics and Mechanics(English Edition) 2011年第11期32卷 1407-1422页

作者： j. KONG D. THUNG Division of Building Science and Technology City University of Hong Kong Hong Kong P. R. China School of Creative Media City University of Hong Kong Hong Kong P. R. China

The spline finite strip method （FSM） is one of the most popular numerical methods for analyzing prismatic structures. Efficacy and convergence of the method have been demonstrated in previous studies by comparing only numerical results with analytical results of some benchmark problems. To date, no exact solutions of the method or its explicit forms of error terms have been derived to show its convergence analytically. As such, in this paper, the mathematical exact solutions of spline finite strips in the plate analysis are derived using a unitary transformation approach （abbreviated as the U-transformation method herein）. These exact solutions are presented for the first time in open literature. Unlike the conventional spline FSM which involves assembly of the global matrix equation and its numerical solution, the U-transformation method decouples the global matrix equation into the one involving only two unknowns, thus rendering the exact solutions of the spline finite strip to be derived explicitly. By taking Taylor＇s series expansion of the exact solution, error terms and convergence rates are also derived explicitly and compared directly with other numerical methods. In this regard, the spline FSM converges at the same rate as a non-conforming finite element, yet involving a smaller number of unknowns compared to the latter. The convergence rate is also found superior to the conventional finite difference method.

关键词： spline finite strip U-transformation plate symmetry

Diapause development in early and late emerging phenotypes of Delia floralis

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Insect Science 2014年第1期21卷 103-113页

作者： Tor j. johansen richard Meadow Arctic Agriculture and Land Use Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research Tromsm plant Health and Plant Protection Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research As Norway

The turnip fly, Delia floralis Fall6n （Diptera： Anthomyiidae） is an important insect pest of brassica vegetable crops in the holarctic region. Different populations have strongly varying temperature requirements for fly emergence, a challenge for accurate prediction of activity. This study focused on diapause development in one early and one late emerging phenotype. The physiological state after various treatments was deduced from emergence data. Our results showed a slow diapause progression at chilling conditions for both populations and diapause ended about 7 months after pupae were formed for the early population. For the late population held at 4℃ diapause did not end, no matter how long the duration of chilling. These pupae required a period with elevated temperatures above 6~C to continue development. At constant non-chilling conditions （18℃） from the time pupae were formed both populations completed diapause most rapidly. These results indicate that chilling delayed, rather than accelerated development and was not a prerequisite for diapause development. For post-diapause, results indicated a linear relationship between rate of development and temperature within the range of 6-18℃and a theoretical base temperature for development of about 2℃ for both populations. In conclusion, D. floralis pupae are in diapause throughout a long winter period, and delayed emergence of the late population appears to be caused by prolonged diapause regulated by a developmental temperature threshold. The study has added information on the biology of turnip fly populations, a prerequisite for improved pest control.

关键词： brassica chilling emergence hibernation quiescence