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Diversity patterns, environmental drivers and changes in vegetation composition in dry inter-Andean valleys

Journal of Plant Ecology 2017年第3期10卷 461-475页

作者： Catalina Quintana Marco Girardello anders s.barfod Henrik Balslev Department of Bioscience Ecoinformatics and Biodiversity GroupAarhus UniversityNy Munkegade 114DK-8000 Aarhus CDenmark Departamento de Ciencias Biológicas Pontificia Universidad Católica del EcuadorAv.12 de Octubre 1076Apartado postal 17012184QuitoEcuador

Aims We studied diversity,patterns of endemism and turnover of veg-etation composition in dry inter-Andean valleys(DIAVs)where lit-tle is known about the influence of the abiotic drivers controlling plant species composition and occurrences,and the life forms that contribute most toα-andβ-diversity,*** study was focused on DIAVs located in the highlands(800-2800 m)around the Equator(1°N-5°s).The following questions were addressed:(i)what differences exist between endemic and non-endemic species in terms of species number,frequency and abundance?(ii)are pat-terns ofα-andβ-diversity correlated with latitude?(iii)what are the major environmental drivers controlling spatial patterns in species composition and occurrence?Methods We established 63 transects of 5×100 m in areas with DIAV vegetation,impacted as little as possible by human *** each transect,all mature trees and shrubs were identified and counted to determine their *** coverage of terrestrial herbs was *** additive models were used to quantify the relationship betweenα-andβ-diversity with *** recordα-diversity,we used the exponential shannon *** sørensen index was used to measureβ-diversity or species *** used canonical correspondence analysis to deter-mine species composition and generalized linear mixed models to quantify simultaneously the determinants of species occur-rence across species and *** models were evaluated using the Akaike information *** analyses were run separately for trees,herbs and *** Findings Overall,we found that shrubs was the most diverse life form,constituting 43%(12%endemic)of the 313 species,followed by herbs(36%;11.5%endemic)and trees(20%;5%endemic).Trees comprise mostly species with low abundance(e.g.s ha^(−1)),which was also true for herbs,whereas shrubs showed a larger number of abundant species(>30 individuals ha^(−1)),includ-ing four endemic *** of the e

关键词： endemics α-diversity β-diversity life forms Ecuador

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The performance of the Noblesse multi-collector noble gas mass spectrometer for ^(40)Ar/^(39)Ar geochronology

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Acta Geochimica 2018年第5期37卷 734-745页

作者： Defeng He Finlay M.stuart Dan N.barfod Fang Xiao Hong Zhong state Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Isotope Geoscience Unit Scottish Universities Environmental Research Centre NERC Argon Isotope Facility Scottish Universities Environmental Research Centre

Noblesse multi-collector noble gas mass spec- trometer is specially designed for multi-collection of Ar isotopes with different beam sizes, especially for small ion beams, precisely, and hence is perfectly suitable for ^40Ar/^39Ar geochronology. We have analyzed widely used sanidine, muscovite, and biotite standards with recom- mended ages of - 1.2-133 Ma, with the aim to assess the reliability of Noblesse for ^40Ar/^39Ar dating. An EsI MIR10 30W CO2 laser was used for total fusion or incremental heating samples. Extracted gases were routinely purified by four sAEs NP10 getters （one at - 400 ℃ and others at room temperature）. A GP50 getter and a metal cold finger cooled by liquid N （- 196 ℃） were also attached for additional purification if necessary. The Ar isotopes were then measured by Noblesse using Faraday or multiplier according to the signal intensities. Over a period of 1.5 months 337 air calibrations produced a weighted mean ^40Ar/^36Ar of 296.50 ± 0.08 （2σ, MsWD = 4.77）. Fish Canyon sanidine is used to calculate J-values, which show good linear relationship with position in irradiation. The age of four mineral standards （Alder Creek sanidine, Brione muscovite, Yabachi sanidine, and Fangshan biotite） are within error of the accepted ages. Five Alder Creek sanidine aliquots yielded an age range of 1.174-1.181 ± 0.013 Ma （2σ） which broadly overlaps the established age of the standard and the uncertainty approaches those of the foremost Ar/Ar laboratories in the world. The weighted mean ages of four Brione muscovite aliquots （18.75 i 0.16 Ma, 2σ）, five Yabachi sanidine aliquots （29.50 ± 0.19 Ma, 2σ）, and three Fangshan bio- tite aliquots （133.0 ± 0.76 Ma, 2σ） are consistent with the recommended values of these standards, and the uncer- tainties are typical of modem Ar/Ar laboratories world- wide.

关键词： Ar/Ar geochronology Multi-collector Highprecision Noblesse Age standard

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Flight initiation distance, color and camouflage

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Current Zoology 2019年第5期65卷 535-540页

作者： anders Pape MOLLER Wei LIANG Diogo s.M.sAMiA Laboratoire d'Ecologie Systematique et EvolutionCNRS UMRUniversite Paris-SudBatiment 362Orsay CedexFrance Ministry of Education Key Laboratory for Biodiversity science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China Ministry of Education Key Laboratory for Ecology of Tropical Islands College of Life SciencesHainan Normal UniversityHaikouChina Department of Ecology Federal University of GoiasGoianiaBrazil

Camouflage is widespread throughout the animal kingdom allowing individuals to avoid detection and hence save time and energy rather than escape from an approaching ***,camouflage is likely to have co-evolved with antipredator ***,we propose that camouflage results in dichotomous escape behavior within and among species with classes of individuals and species with cryptic coloration having shorter flight initiation distances(FIDs;the distance at which an individual takes flight when approached by a human).We report the results of 2 tests of this ***,bird species with cryptically colored plumage have consistently shorter FID than closely related species without such *** species with sexually dimorphic plumage,brightly colored adult male common pheasants Phasianus colchicus and golden pheasants Chrysolophus pictus have long and variable FID,whereas cryptically colored juveniles and adult females have short and invariable ***,FID in females was predicted by presence or absence of cryptic color,FID in males and their *** findings are consistent with the hypothesis that risk-taking behavior has been attuned to camouflage,and that species with different levels of camouflage differ consistently in their FID.

关键词： anti-predator behavior birds camouflage crypsis sexual dichromatism

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Why are sexually selected weapons almost absent in females？

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Current Zoology 2013年第4期59卷 564-568页

作者： anders BERGLUND Department of Ecology and Genetics/Animal Ecology Uppsala University Norbyv. 18d 752 36 Uppsala Sweden

In sex role reversed species, predominantly females evolve sexually selected traits, such as ornaments and/or weapons. Female ornaments are common and their function well documented in many species, whether sex role reversed or not. However, sexually selected female weapons seem totally absent except for small wing spurs in three jacana species, present in both males and females. This poor female weaponry is in sharp contrast to the situation in species with conventional sex roles： males com- monly have evolved sexually selected weapons as well as ornaments. At the same time, females in many taxa have naturally se- lected weapons, used in competition over resources or in predator defence. Why are sexually selected weapons then so rare, al- most absent, in females？ Here I briefly review weaponry in females and the function of these weapons, conclude that the near ab- sence of sexually selected weapons begs an explanation, and suggest that costs of sexually selected weapons may exceed costs of ornaments. Females are more constrained when evolving sexually selected traits compared to males, at least compared to those males that do not provide direct benefits, as trait costs reduce a female＇s fecundity. I suggest that this constraining trade-off between trait and fecundity restricts females to evolve ornaments but rarely weapons. The same may apply to paternally investing males. Whether sexually selected weapons actually are more costly than sexually selected ornaments remains to be investigated

关键词： sexual selection Female weapons Female ornaments sex role reversal

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Extra-pair paternity and antiparasitic defence

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Avian Research 2020年第4期11卷 391-397页

作者： anders Pape Møller Jørgen skavdal søraker Juan Josésoler Ministry of Education Key Laboratory for Biodiversity science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China Ecologie systématique et Evolution UniversitéParis-SaclayCNRSAgroParisTech91405 OrsayFrance Centre for Biodiversity Dynamics Department of BiologyNorwegian University of Science and TechnologyHøgskoleringen 5No-7491TrondheimNorway Depto.Ecología Funcional y Evolutiva Estación Experimental de ZonasÁridasCtra.Sacramento S/NLa Cañada de San Urbano04120 AlmeríaSpain

Background:Extra-pair paternity(EPP)in birds provides benefits in terms of more offspring,and characteristics for maintenance of this behaviour have been the subject of *** are known to be transmitted during mating,especially when mating with multiple partners,and factors reducing this cost of multiple mating are ***,plumage brightness and colour intensity have been shown to be important traits to benefits from multiple mating as predicted by sexual *** aim of this study was to investigate the relationship between the rate of extra-pair paternity and the relative size of the uropygial gland at the interspecific level,as the uropygial gland is an exocrine gland hypothesized to produce antiparasitic substances and further identified to affect plumage *** of the expected benefits of large uropygial gland in scenarios of sexual selection,we predicted a positive correlation with ***:We collected information from the literature of uropygial gland size and frequency of extra-pair paternity of 60 avian species of different families and explored the predicted positive correlation between *** did so with means of comparative analyses that considered phylogenetic relationship as random factor and included body mass as *** used Markov chain Monte Carlo generalized linear mixed models that were weighted by number of nests used to estimate extra-pair ***:We detected a positive relationship between level of extra-pair paternity and uropygial gland size at an interspecific *** finding is consistent with the ***:We discuss the importance of this result in scenarios of sexual selection and argue that the detected relationship may have arisen by utilizing antiparasitic secretions through secondary sexual characters indicating parasite resistance.

关键词： Antiparasitic defence Costs of extra-pair paternity Microorganisms Uropygial gland Uropygial secretions

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Transrectal ultrasound and magnetic resonance imaging measurement of extramural tumor spread in rectal cancer

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World Journal of Gastroenterology 2012年第36期18卷 5021-5026页

作者： sφren R Rafaelsen Chris Vagn-Hansen Torben sφrensen John Plφen anders Jakobsen Department of Radiology DCCG SouthInstitute of Regional Health Services ResearchUniversity of Southern DenmarkVejle HospitalKabbeltoft 257100 VejleDenmark Department of Oncology DCCG SouthInstitute of Regional Health Services ResearchUniversity of Southern DenmarkVejle HospitalKabbeltoft 257100 VejleDenmark

AIM： To evaluate the agreement between transrectal ultrasound （TRUs） and magnetic resonance imaging （MRI） in classification of ≥ T3 rectal tumors. METHODs： From January 2010 to January 2012, 86 consecutive patients with ≥ T3 tumors were included in this study. The mean age of the patients was 66.4 years （range： 26-91 years）. The tumors were all ≥ T3 on TRUs. The sub-classification was defined by the penetration of the rectal wall： a： 0 to 1 mm; b： 1-5 mm, c： 6-15; d：〉 15 mm. Early tumors as ab （≤ 5 ram） and advanced tumors as cd （〉 5 mm）. All patients underwent TRUs using a 6.5 MHz transrectal transducer. The MRI was performed with a 1.5 T Phil- ips unit. The TRUs findings were blinded to the radiol- ogist performing the interpretation of the MRI images and measuring the depth of extramural tumor spread REsULTs： TRUs found 51 patients to have an early ≥ T3 tumors and 35 to have an advanced tumor, where- as MRI categorized 48 as early ≥ T3 tumors and 38 as advanced tumors. No patients with tumors classified as advanced by TRUs were found to be early on MRI. The kappa value in classifying early versus advanced T3 rectal tumors was 0.93 （95% CI： 0.85-1.00）. We found a kappa value of 0.74 （95% CI： 0.63-0.86） for the total sub-classification between the two methods. The mean maximal tumor outgrowth measured by TRUs, 5.5 mm ± 5.63 mm and on MRI, 6.3 mm ±6.18 mm, P = 0.004. In 19 of the 86 patients the following CT scan or surgery revealed distant metastases; of the 51 patients in the ultrasound ab group three （5.9%） had metastases, whereas 16 （45.7%） of 35 in the cd group harbored distant metastases, P = 0.00002. The odds ratio of having distant metastases in the ultra- sound cd group compared to the ab group was 13.5 （95% CI： 3.5-51.6）, P = 0.00002. The mean maximal ultrasound measured outgrowth was 4.3 mm （95% CI： 3.2-5.5 mm） in patients without distant metastases, while the mean maximal outgrowth was 9.5 mm （95% CI： 6.2-12.8 ram） in the patients with metastases, P = 0

关键词： Ultrasound Magnetic resonance imaging Rectal cancer Tumor staging Metastases

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Bottom-up approaches to microLEDs emitting red, green and blue light based on GaN nanowires and relaxed InGaN platelets

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Chinese Physics B 2023年第1期32卷 1-10页

作者：毕朝霞 anders Gustafsson Lars samuelson anders Gustafsson and Lars Samuelson Division of Solid State Physics and NanoLundLund UniversityBox 118SE-22100 LundSweden

Miniaturization of light-emitting diodes(LEDs) with sizes down to a few micrometers has become a hot topic in both academia and industry due to their attractive applications on self-emissive displays for high-definition televisions,augmented/mixed realities and head-up displays, and also on optogenetics, high-speed light communication, etc. The conventional top-down technology uses dry etching to define the LED size, leading to damage to the LED side *** sizes of microLEDs approach the carrier diffusion length, the damaged side walls play an important role, reducing microLED performance significantly from that of large area LEDs. In this paper, we review our efforts on realization of microLEDs by direct bottom-up growth, based on selective area metal–organic vapor phase epitaxy. The individual LEDs based on either GaN nanowires or InGaN platelets are smaller than 1 μm in our approach. such nano-LEDs can be used as building blocks in arrays to assemble microLEDs with different sizes, avoiding the side wall damage by dry etching encountered for the top-down approach. The technology of InGaN platelets is especially interesting since InGaN quantum wells emitting red, green and blue light can be grown on such platelets with a low-level of strain by changing the indium content in the InGaN platelets. This technology is therefore very attractive for highly efficient microLEDs of three primary colors for displays.

关键词： microLEDs RGB GaN InGaN

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Methods of modeling relative growth rate

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Forest Ecosystems 2015年第2期2卷 82-90页

作者： Arne Pommerening anders Muszta Department of Forest Resource Management Faculty of Forest SciencesSwedish University of Agricultural Sciences SLU

Background： Analysing and modelling plant growth is an important interdisciplinary field of plant science. The use of relative growth rates, involving the analysis of plant growth relative to plant size, has more or less independently emerged in different research groups and at different times and has provided powerful tools for assessing the growth performance and growth efficiency of plants and plant populations. In this paper, we explore how these isolated methods can be combined to form a consistent methodology for modelling relative growth rates. Methods： We review and combine existing methods of analysing and modelling relative growth rates and apply a combination of methods to sitka spruce （Piceo sitchensis （Bong.） Carr.） stem-analysis data from North Wales （UK） and British Douglas fir （Pseudotsugd menziesii （Mirb.） Franco） yield table data. Results： The results indicate that, by combining the approaches of different plant-growth analysis laboratories and using them simultaneously, we can advance and standardise the concept of relative plant growth. Particularly the growth multiplier plays an important role in modelling relative growth rates. Another useful technique has been the recent introduction of size-standardised relative growth rates. Conclusions： Modelling relative growth rates mainly serves two purposes, 1） an improved analysis of growth performance and efficiency and 2） the prediction of future or past growth rates. This makes the concept of relative growth ideally suited to growth reconstruction as required in dendrochronology, climate change and forest decline research and for interdisciplinary research projects beyond the realm of plant science.

关键词： Growth efficiency Growth coefficient/multiplier Chapman-Richards growth model standardisation simultaneous estimations

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Topology optimization of 3D shell structures with porous infill

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Acta Mechanica sinica 2017年第4期33卷 778-791页

作者： anders Clausen Erik Andreassen Ole sigmund Department of Mechanical Engineering Solid MechanicsTechnical University of Denmark 2800 Lyngby Denmark

This paper presents a 3D topology optimization approach for designing shell structures with a porous or void interior. It is shown that the resulting structures are significantly more robust towards load perturbations than completely solid structures optimized under the same conditions. The study indicates that the potential benefit of using porous structures is higher for lower total volume *** to earlier work dealing with 2D topology optimization, we found several new effects in 3D problems. Most notably, the opportunity for designing closed shells significantly improves the performance of porous structures due to the sandwich effect. Furthermore, the paper introduces improved filter boundary conditions to ensure a completely uniform coating thickness at the design domain boundary.

关键词： porous shells topology interior perturbations opportunity dealing earlier stiffness struc

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Typicality at quantum-critical points

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Chinese Physics B 2018年第8期27卷 517-528页

作者： Lu Liu anders W sandvik Wenan Guo Department of Physics Beijing Normal UniversityBeijing 100875China 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 discuss the concept of typicality of quantum states at quantum-critical points, using projector Monte Carlo simu- lations of an s ---- 1/2 bilayer Heisenberg antiferromagnet as an illustration. With the projection （imaginary） time t scaled as t= aLz, L being the system length and z the dynamic critical exponent （which takes the value z = 1 in the bilayer model studied here）, a critical point can be identified which asymptotically flows to the correct location and universality class with increasing L, independently of the prefactor a and the initial state. Varying the proportionality factor a and the initial state only changes the cross-over behavior into the asymptotic large-L behavior. In some cases, choosing an optimal factor a may also lead to the vanishing of the leading finite-size corrections. The observation of typicality can be used to speed up simulations of quantum criticality, not only within the Monte Carlo approach but also with other numerical methods where imaginary-time evolution is employed, e.g., tensor network states, as it is not necessary to evolve fully to the ground state but only for sufficiently long times to reach the typicality regime.

关键词： typicality quantum criticality bilayer Heisenberg antiferromagnet model imaginary projectingtime, projecting quantum Monte Carlo simulation

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