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Phenotype manipulation influences microhabitat choice in pygmy grasshoppers

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Current Zoology 2012年第3期58卷 392-400页

作者： lena WENNERSTEN Einat KARPESTAM anders FORSMAN School of Natural Sciences Linnaeus University SE-391 82 Kalmar Sweden

The matching habitat choice hypothesis posits that individuals actively choose those microhabitats that best match their specific phenotype to maximize fitness. Despite the profound implications, matching habitat choice has not been unequivo- cally demonstrated. We conducted two experiments to examine the impact of pigmentation pattern in the color polymorphic pygmy grasshopper Tetrix subulata on habitat choice in a laboratory thermal mosaic arena. We found no behavioral differences in the thermal mosaic among pygmy grasshoppers belonging to either pale, intermediate or dark natural color morphs. However, af- ter manipulating the grasshoppers＇ phenotype, the utilization through time of warmer and colder parts of the arena was different for black-painted and white-painted individuals. White-painted individuals used warmer parts of the arena, at least during the ini- tial stage of the experiment. We conclude that microhabitat choice represents a form of behavioural plasticity. Thus, even if the choice itself is flexible and not genetically determined, it can still lead to spatial genetic structure in the population because the phenotypes themselves may be genetically mediated [Current Zoology 58 （3）： 392--400, 2012].

关键词： Behavioral plasticity Color polymorphism Integrated phenotypes Microhabitat use Tetrix Thermoregulation

Tunable deconfined quantum criticality and interplay of different valence-bond solid phases

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Chinese Physics B 2020年第5期29卷 52-65页

作者： Bowen Zhao Jun Takahashi anders W.Sandvik Department of Physics Boston University590 Commonwealth AvenueBostonMassachusetts 02215USA Beijing National laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China

We use quantum Monte Carlo simulations to study an S = 1/2 spin model with competing multi-spin interactions. We find a quantum phase transition between a columnar valence-bond solid(cVBS) and a Néel antiferromagnet(AFM), as in the scenario of deconfined quantum-critical points, as well as a transition between the AFM and a staggered valence-bond solid(sVBS). By continuously varying a parameter, the sVBS–AFM and AFM–cVBS boundaries merge into a direct sVBS–cVBS transition. Unlike previous models with putative deconfined AFM–cVBS transitions, e.g., the standard J–Q model,in our extended J–Q model with competing cVBS and sVBS inducing terms the transition can be tuned from continuous to first-order. We find the expected emergent U(1) symmetry of the microscopically Z4 symmetric cVBS order parameter when the transition is continuous. In contrast, when the transition changes to first-order, the clock-like Z4 fluctuations are absent and there is no emergent higher symmetry. We argue that the confined spinons in the sVBS phase are *** also present results for an SU(3) symmetric model with a similar phase diagram. The new family of models can serve as a useful tool for further investigating open questions related to deconfined quantum criticality and its associated emergent symmetries.

关键词： quantum phase transitions deconfined quantum criticality quantum spin systems quantum Monte Carlo simulations

Acupuncture Points Used in the Prophylaxis against Recurrent Uncomplicated Cystitis, Patterns Identified and Their Possible Relationship to Physiological Measurements

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Chinese Journal of Integrative Medicine 2016年第7期22卷 510-517页

作者： Terje Alraek anders Baerheim Steven Birch The National Research Center in Complementary and Alternative Medicine Department of Community Medicine Faculty of Health Science UiT The Arctic University of Norway University College of Health Sciences Institute of Acupuncture Faculty of Medicine and Dentistry Department of Global Health and Primary Care University of Bergen

Objective： To explore the correlation between single acupoints used and the recurrence rate of cystitis among cystitis-prone women receiving acupuncture as a prophylactic treatment. Methods： In all, 58 cystitis-prone women were included in the analysis. Customised acupuncture treatments were given twice a week, over 4 weeks. The main effect parameter was the number of cystitis episodes during the 6-month observation time. Residual urine was measured at baseline, 2, 4 and 6 months using portable ultrasound equipment. Sympathetic and vagotone nerve activities were measured by using skin conductance and respiratory sinus arrhythmia, respectively. Results： The main acupoints used for patients with Kidney （Shen） qi/yang deficiency were Shenshu （Bl23）, Taixi （KI3）, Zhongji （CV3）, Sanyinjiao （SP6） and Pangguangshu （Bl2.8）, compared with Taichong （lR3）, CV3, Bl28, Yinlingquan （SP9） and SP6 for liver （Gan） qi stagnation, and SP6, CV3, Bl28, Zusanli （ST36） and SP9 for Spleen （Pi） qi/yang deficiency patients. The combination Bl23 and KI3 were used in 16 women, 13 of which were Kidney pattern related patients. When used, the number of symptomatic episodes were reduced to a third compared with what occurred in the 42 women where this combination was not used （3/16 vs. 28/42, P〈0.05）. Bl23 application correlated to a significant reduction in residual urine measured a few days after treatment. Patients with the pattern of Spleen qi/yang deficiency had an initial increase in residual urine after treatments. Conclusion： Treating Kidney pattern related patients with the combination of Bl23 and KI3 resulted in far better outcome than other points/combination of points for other Chinese medicine diagnoses. The acupoint SP6 may be less indicated than previously assumed when treating cvstitis-Drone women DroDhvlacticalIv.

关键词： acupuncture point recurrent urinary tract infection Chinese medicine pattern identification,syndrome differentiation women

Coarse-Grained langevin Approximations and Spatiotemporal Acceleration for Kinetic Monte Carlo Simulations of Diffusion of Interacting Particles

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Chinese Annals of Mathematics,Series B 2009年第6期30卷 653-682页

作者： Sasanka ARE Markos A. KATSOUlAKIS anders SZEPESSY Department of Mathematics and Statistics University of MassachusettsAmherstMA 01003-9305USA Department of Applied Mathematics University of Crete and Foundation of Research and TechnologyHellasHeraklion 71405Greece Matematiska Institutionen Kungliga Tekniska Hgskolan (Royal Institute of Technology)SE-100 44 StockholmSweden

Kinetic Monte Carlo methods provide a powerful computational tool for the simulation of microscopic processes such as the diffusion of interacting particles on a surface, at a detailed atomistic level. However such algorithms are typically computationatly expensive and are restricted to fairly small spatiotemporal scales. One approach towards overcoming this problem was the development of coarse-grained Monte Carlo algorithms. In recent literature, these methods were shown to be capable of efficiently describing much larger length scales while still incorporating information on microscopic interactions and fluctuations. In this paper, a coarse-grained langevin system of stochastic differential equations as approximations of diffusion of interacting particles is derived, based on these earlier coarse-grained models. The authors demonstrate the asymptotic equivalence of transient and long time behavior of the langevin approximation and the underlying microscopic process, using asymptotics methods such as large deviations for interacting particles systems, and furthermore, present corresponding numerical simulations, comparing statistical quantities like mean paths, auto correlations and power spectra of the microscopic and the approximating langevin processes. Finally, it is shown that the langevin approximations presented here are much more computationally efficient than conventional Kinetic Monte Carlo methods, since in addition to the reduction in the number of spatial degrees of freedom in coarse-grained Monte Carlo methods, the langevin system of stochastic differential equations allows for multiple particle moves in a single timestep.

关键词： Kinetic Monte Carlo methods Diffusion Fluctuations

Niche segregation, competition, and urbanization

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Current Zoology 2018年第2期64卷 145-152页

作者： anders PAPE MФllER Mario DiAz Ecologie Systematique Evolution CNRS Universite Paris-Sud AgroParisTech Universite Pari-Saclay OrsayCedex F-91400 France Department of Biogeography and Global Change (BGC-MNCN-CSIC) NationalMuseum of Natural Sciences CSIC c/Serrano 155bis Madrid E-28006 Spain

Urbanization of species is an ongoing process where successful urban colonizers usually obtain large fitness benefits. Mechanisms proposed to explain associations between urbanization and lifehistory traits are based on behavioral flexibility in food and habitat use and reduced fear responses. We test the novel hypothesis that interspecific competition for proximity to humans is driving ur- banization. We recorded the distance during the breeding season to human habitation for 50 pairs of closely related bird species, where one was closely associated with humans while the other species was not. The degree of urbanization was larger as was range size and abundance in the species more closely associated to humans. Flight initiation distance was shorter, and species closely associated with humans were more abundant in ancestral rural habitats. likewise, species more closely associated with humans reproduced earlier and during longer periods. These results are consistent with the hypothesis that urbanization is promoted by interspecific competition. Resulting isolation by urban habitat may further facilitate contemporary adaptation to urban environments.

关键词： birds distance to human habitation isolation by habitat isolation by time mechanisms.

Plumage brightness and uropygial gland secretions in barn swallows

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Current Zoology 2019年第2期65卷 177-182页

作者： anders PAPE MOllER Fernando MATEOS-GONZAlEZ Ecologie Systematique Evolution Universite Paris-Sud CNRS AgroParisTech Universite Paris-Saclay Batiment 362 F-91405 Orsay Cedex France Department of Ecology and Genetics Evolutionary Biology Centre University of Uppsala Norbyvagen 18d SE-75236 Uppsala Sweden

The uropygial gland has been hypothesized to play a role in sexual signaling through a "make-up" function derived from the effects of secretions from the gland on the appearanee of the plumage and bare parts of the body. Here we show that plumage brightness of dorsal feathers of individual barn swallows Hirundo rustica was greater in mated than in unmated individuals. In addition, plumage brightness in creased with colony size. Furthermore, plumage bright ness was positively correlated with the amount of wax in the uropygial gland, negatively correlated with time of sampling of uropygial wax (perhaps because more wax is present early in the morning after an entire night of wax production without any preening), and negatively correlated with the number of chewing lice that degrade the plumage. Experimentally preventing barn swallows from access to the uropygial gland reduced plumage brightness, showing a causal link between secretions from the uropygial gland and plumage brightness. These findings provide evidence consistent with a role of uropygial secretions in signaling plumage brightness.

关键词： brightness coloration preening wax sexual selection uropygial gland

Farmers' contributions to the conservation of tree diversity in the Groundnut Basin,Senegal

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Journal of Forestry Research 2017年第5期28卷 1083-1096页

作者： Antoine Sambou Bienvenu Sambou anders R?bild Department of Geosciences and Natural Resource Management Faculty of ScienceUniversity of Copenhagen Institut des Sciences de l'Environnement (ISE) Facultdes Sciences et TechniqueUniversitCheikh Anta Diop(UCAD)

Tree diversity in West Africa is threatened by intensified land uses and salinization, and farmers’ role in conservation of tree species is unclear. We hypothesized that farmers contribute to conservation of tree diversity through protection of trees in their agroforestry landscapes and compared the diversity and structure of the tree vegetation across landscape classes. Inventories were carried out in three villages in the Groundnut Basin in Senegal, assessing tree diversity, density and crown cover. Tree diversity as assessed by species accumulation curves was high in forests, but cultivated landscapes had comparable or almost comparable diversity, especially in the cases where the forest was planted or was affected by charcoal production. However, the occurrence of exotic species was higher in cultivated parts of the landscape, and although many species were in common, ordination plots indicated that forests and cultivated landscapes to some degree had different species composition. Salinity had a strong influence on vegetation, not only in the tans (salt marshes) but also across the other landscape classes. In conclusion, agroforestry landscapes in the three villages harbor considerable tree diversity, but insufficient to fully conserve the tree species. We argue that informing and including farmers in tree management in the region will contribute to overall conservation of tree genetic resources.

关键词： Tree diversity Conservation-landscape classes Environmental factors Groundnut Basin

High frame rate multi-resonance imaging refractometry with distributed feedback dye laser sensor

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light(Science & Applications) 2015年第1期4卷 410-414页

作者： Christoph Vannahme Martin Dufva anders Kristensen Technical University of Denmark Department of Micro-and NanotechnologyDTU NanotechDK-2800 Kgs.LyngbyDenmark

High frame rate and highly sensitive imaging of refractive index changes on a surface is very promising for studying the dynamics of dissolution,mixing and biological processes without the need for ***,a highly sensitive distributed feedback(DFB)dye laser sensor for high frame rate imaging refractometry without moving parts is *** dye lasers are low-cost and highly sensitive refractive index *** unique multi-wavelength DFB laser structure presented here comprises several areas with different grating *** two dimensions of space is enabled by analyzinglaser light from all areasin parallelwith an imaging *** this multi-resonance imaging refractometry method,the spatial position in one direction is identified from the horizontal,i.e.,spectral position of the multiple laser lines which is obtained from the spectrometer charged coupled device(CCD)*** orthogonal spatial position is obtained from the vertical spatial position on the spectrometer CCD array as in established spatially resolved ***,the imaging technique is demonstrated by monitoring the motion of small sucrose molecules upon dissolution of solid sucrose in *** omission of moving parts improves the robustness of the imaging system and allows a very high frame rate of up to 12 Hz.

关键词： distributed feedback laser label-free imaging laser sensor refractive index sensor

Extensive reworking of Archaean crust within the Birimian terrane in Ghana as revealed by combined zircon U-Pb and lu-Hf isotopes

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Geoscience Frontiers 2018年第1期9卷 173-189页

作者： Andreas Petersson anders Scherstén Axel Gerdes Department of Geology Lund UniversitySolvegatan 12SE-223 62 LundSweden Centre for Exploration Targeting School of Earth and EnvironmentUniversity of Western AustraliaCrawleyAustralia Department of Geosciences Swedish Museum of Natural History104 05 StockholmSweden Institut für Geowissenschaften Senckenberganlage 28D-60054 Frankfurt am MainGermany

located in the southeastern parts of the BaouléMossi domain of the West African Craton,the Birimian terrane in Ghana is known to consist of predominantly juvenile crust emplaced during the Eburnean *** we present novel coupled zircon U-Pb and lu-Hf isotope data from nine Birimian granitoids intruding different domains from northwestern,western and southeastern ***-chondriticε_(Hf)-values indicating reworking of Archaean crust are recorded in zircon from both northwestern and southeastern *** a conservative estimate 71%of all analysed zircon grains spanning in age from2220 Ma to 2130 Ma require contribution from a reworked Archaean source,contradicting the common belief that the Birimian terrane consist of predominantly juvenile crust.A minimumε_(Hf)-value of-10.5 at2139 Ma suggests a Palaeoarchaean to late Mseoarchaean component as the contributing ancient *** with previously reported heavy zirconδ^(18)O signatures from Birimian river zircon in Ghana,our new data suggests reworking of Archaean aged sediments during subduction initiated crustal growth in the vicinity of one,or possibly in between two Archaean aged cratons.

关键词： Birimian Baoulé Mossi Archaean Crustal growth Zircon