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Insect Science 2015年第6期22卷 821-828页

作者： Eduardo m. Soto maria I. L. Betti juan Hurtado Esteban Hasson Departamento de Ecologia Genetica y Evolucion IEGEBA (CONICET-UBA) Facultad de Ciencias Exactas y Naturales Universidad deBuenos Aires Buenos Aires Argentina

The preference-performance relationship in plant-insect interactions is a cen- tral theme in evolutionary ecology. Among many insects, eggs are vulnerable and larvae have limited mobility, making the choice of an appropriate oviposition site one of the most important decisions for a female. We investigated the evolution of oviposition preferences in Drosophila melanogaster meigen and Drosophila simulans Sturtevant by artificially selecting for the preference for 2 natural resources, grape and quince. The main finding of our study is the differential responses of D. melanogaster and D. simulans. Although preferences evolved in the experimental populations of D. melanogaster, responses were not consistent with the selection regimes applied. In contrast, responses in D. simulans were consistent with expectations, demonstrating that this species has selectable genetic variation for the trait. Furthermore, crosses between D. simulans divergent lines showed that the genetic factors involved in grape preference appear to be largely recessive. In summary, our artificial selection study suggests that D. melanogaster and D. simulans possess different genetic architectures for this trait.

关键词： artificial selection behavior Drosophila genetic variation naturalresources oviposition preference

Partitioning a Graph into Defensive k-Alliances

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Acta mathematica Sinica,English Series 2011年第1期27卷 73-82页

作者： Ismael G.YERO Sergio BERmUDO juan A.RODRiGUEZ-VELAZQUEZ Jose m.SIGARRETA Department of Computer Engineering and mathematics Rovira i Virgili UniversityAv.Pai'sos Catalans 2643007 TarragonaSpain Department of Economy Quantitative Methods and Economic HistoryPablo de Olavide UniversityCarretera de Utrera Kin.141013-SevillaSpain Department of Computer Engineering and mathematics Rovira i Virgili UniversityAv.Paisos Catalans 2643007 TarragonaSpain Faculty of mathematics Autonomous University of GuerreroCarlos E.Adame 5Co1.La GaritaAcapulcoGuerreroMexico

A defensive k-alliance in a graph is a set S of vertices with the property that every vertex in S has at least k more neighbors in S than it has outside of S. A defensive k-alliance S is called global if it forms a dominating Set. In this paper we study the problem of partitioning the vertex set of a graph into （global） defensive k-alliances. The （global） defensive k-alliance partition number of a graph Г = （V, E）, ψkgd（F）） ψkd（F）, is defined to be the maximum number of sets in a partition of V such that each set is a （global） defensive k-alliance. We obtain tight bounds on ψkd（F） and ψkgd（F） in terms of several parameters of the graph including the order, size, maximum and minimum degree, the algebraic connectivity and the isoperimetric number. moreover, we study the close relationships that exist among partitions of F1 × F2 into （global） defensive （kl ＋ k2）-alliances and partitions of Fi into （global） defensive ki-alliances, i ∈ {1, 2}.

关键词： Defensive alliances dominating sets domination isoperimetric number

Editorial:Special issue on distributed computing and artificial intelligence

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Frontiers of Information Technology & Electronic Engineering 2016年第4期17卷 281-282页

作者： juan m.CORCHADO Li WEIGANG Javier BAJO Fei WU Tian-cheng LI University of Salamanca Spain University of Brasilia Brazil Polytechnic University of madrid Spain Zhejiang University China

4:1!Google’s artificial intelligence(AI)program,Alpha Go,has won Go master Lee Sedol in a best-of-five competition held in Korean march 9-15,*** by many as a landmark moment for AI,the outcome did not come as a surpr... 详细信息

关键词：人工智能分布式计算编辑计算机科学分布式环境智能算法优良组合蒙特卡洛

Photometric and spectroscopic study of flares on Ross 15

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Research in Astronomy and Astrophysics 2021年第1期21卷 67-74页

作者： Jian-Ying Bai Ali Esamdin Xing Gao Yan Yan juan-juan Ren Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

We conducted photometric and spectroscopic observations of Ross 15 in order to further study the flare properties of this less observed flare star.A total of 28 B-band flares are detected in 128 hr of photometric observations,leading to a total flare rate of 0.22-0.040.04 h-1,more accurate than that provided by previous *** give the energy range of the B-band flare(1029.5-1031.5 erg) and the flare frequency distribution(FFD) for the *** the same energy range,the FFD is lower than that of GJ 1243(m4)and YZ Cmi(m4.5),roughly in the middle of those of three m5-type stars and higher than the average FFDs of spectral types> *** performed,for the first time for Ross 15,simultaneous high-cadence spectroscopic and photometric observations,resulting in detection of the most energetic flare in our *** intensity enhancements of the continuum and Balmer lines with significant correlations between them are detected during the flare,which is the same as those of other deeply studied flare stars with similar spectral type.

关键词： stars:flare stars:activity stars:late-type

Review of 500 single incision laparoscopic colorectalsurgery cases-Lessons learned

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World Journal of Gastroenterology 2016年第2期22卷 659-667页

作者： Deborah S Keller juan R Flores-Gonzalez Sergio Ibarra Eric m Haas Colorectal Surgical Associates HoustonTX 77054United States Division of Colon and Rectal Surgery Houston Methodist HospitalThe University of Texas Medical School at HoustonHoustonTX 77054United States Division of minimally Invasive Surgery Department of SurgeryThe University of Texas Medical School at HoustonHoustonTX 77054United States

Single incision laparoscopic surgery(SILS) is a minimally invasive platform with specific benefits over traditional multiport laparoscopic surgery. The safety and feasibility of SILS has been proven, and the applications continue to grow with experience. After 500 cases at a high-volume, single-institution, we were able to standardize instrumentation and operative steps, as well as develop adaptations in technique to help overcome technical and ergonomic challenges. These technical adaptations have allowed the successful application of SILS to technically difficult patient populations, such as pelvic cases, inflammatory bowel disease cases, and high body mass index patients. This review is a frame of reference for the application and wider integration of the single incision laparoscopic platform in colorectal surgery.

关键词： Laparoscopic colectomy minimally invasivecolorectal surgery Single-incision laparoscopic surgery

Heterostructure and Q-factor engineering for low-threshold and persistent nanowire lasing

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Light(Science & Applications) 2020年第1期9卷 1609-1618页

作者： Stefan Skalsky Yunyan Zhang juan Arturo Alanis HAruni Fonseka Ana m.Sanchez Huiyun Liu Patrick Parkinson Department of Physics and Astronomy and The Photon Science Institute The University of ManchesterManchester M139PLUK Department of Electronic and Electrical Engineering University College LondonLondon WC1E 7JEUK Department of Physics University of WarwickCoventry CV47ALUK

Continuous room temperature nanowire lasing from silicon-integrated optoelectronic elements requires careful optimisation of both the lasing cavity Q-factor and population inversion *** apply time-gated optical interferometry to the lasing emission from high-quality GaAsP/GaAs quantum well nanowire laser structures,revealing high Q-factors of 1250±90 corresponding to end-facet reflectivities of R=0.73±*** using optimised direct-indirect band alignment in the active region,we demonstrate a well-refilling mechanism providing a quasifour-level system leading to multi-nanosecond lasing and record low room temperature lasing thresholds(~6μJ cm^(−2) pulse−1)for Ⅲ-Ⅴ nanowire *** findings demonstrate a highly promising new route towards continuously operating silicon-integrated nanolaser elements.

关键词： lasing alignment interferometry

Enhancing output performance of triboelectric nanogenerator by increasing charge storage capacity of electrodes

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Nano Research 2025年第1期18卷 395-403页

作者： Congcong Hao Zekun Wang mingzhe Cai Shuaining Cheng Zhongxin Wang Cong Zhai juan Cui Yongqiu Zheng Chenyang Xue Key Laboratory of Instrumentation Science and Dynamic measurement ministry of Education North University of ChinaTaiyuan 030051China

ABSTRACT:The practical application of rotating triboelectric nanogenerators is often limited by the wear of high-friction surface materials and low surface charge *** addition to the charge pump replenishment strategy,suppressing charge decay is also crucial for increasing surface charge ***,we present a high performance rotary triboelectric nanogenerator(HPR-TENG)based on a coplanar charge pumping strategy and polyvinyl chloride(PVC)*** has been demonstrated that applying PVC film to the surface of the storage electrode of the main TENG(m-TENG)significantly enhances the m-TENG’s output ***,the HPR-TENG with three layers of PVC film pasted achieved the best output performance,with a peak-topeak output voltage of 2828 V,a peak-to-peak output current of 327μA and a charge transfer of 0.81μC at 500 *** addition,the output improvement effects of different materials are *** TENG with 3 layers of PVC film pasted on it has a maximum output power of 748 mW at a load resistance of 4×10^(6)Ω.HPR-TENG’s output performance remains consistent after 100,000 cycles,which shows excellent *** excellent electrical performance of the HPR-TENG can be used as the energy supply for the tip high-voltage breakdown sensor system,which can achieve 14 breakdowns in 10 *** to its extraordinary electrical performance,HPRTENG can not only serve as an energy supply for cutting-edge high-voltage breakdown sensor systems,but also has the potential to serve as an energy supply for high-pressure sterilization,high-pressure vacuum and water electrolysis.

关键词： triboelectric nanogenerator coplanar charge pump enhancing charge density suppressing charge decay polyvinyl chloride(PVC)film

Constraint Cooling of Hot Rolled Coil

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Journal of Iron and Steel Research International 2004年第5期11卷 37-40页

作者： WANGLi-juan ZHANGChun-li NortheasternUniversity Shenyang110004China ShanghaiBaosteelGroupCo Shanghai201900China

Amorphous ribbons of Fe 74Al 4Sn 2(PSiB) 20 alloy have been synthesized by melt spinning and axial design method. The thermal properties of the amorphous ribbons have been measured by differential scanning calorimeter (DSC). The DSC results show that the Fe 74Al 4Sn 2P 12Si 4B 4 amorphous alloy has relatively wider supercooled liquid region with a temperature interval of 40 38 K (ΔT x=T x-T g). The alloys with a higher phosphorous content in the metalloid element composition triangle of Fe 74Al 4Sn 2(PSiB) 20 have high glass forming ability. The amorphous alloys also show good magnetic properties in which Fe 74Al 4Sn 2P 6 67Si 6 67B 6 67 alloy has a large maximum permeability (μ m), Fe 78Al 4Sn 2P 3Si 3B 10 alloy exhibits a high square ratio (B r/B 10) and Fe 74Al 4Sn 2P 4Si 12B 4 shows a low core loss (P 0 5/1 3T). High glass forming ability and good magnetic properties make Fe 74Al 4Sn 2(PSiB) 20 amorphous alloys valuable in future research.

关键词： iron-based amorphous alloys soft magnetic properties supercooled liquid region melt spinning

Knowledge arising from long-term research of variable retention harvesting in Tierra del Fuego: where do we go from here?

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Ecological Processes 2019年第1期8卷 318-333页

作者： Guillermo J.martínez Pastur Yamina m.Rosas mónica Toro manríquez Alejandro Huertas Herrera juan A.miller juan m.Cellini marcelo D.Barrera Pablo L.Peri maría V.Lencinas Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina Universidad Nacional de la Plata(UNLP) Calle 7 e/47 y 48(1900)La PlataBuenos AiresArgentina Instituto Nacional de Tecnología Agropecuaria(INTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)cc 332(9400)Río GallegosSanta CruzArgentina

Nothofagus pumilio forests in Tierra del Fuego are the southernmost forests in the world,where extreme climate conditions represent a challenge to attain sustainable forest *** forestry was proposed as an alternative to increase the species conservation in managed ***,we synthetized results related to the implementation of a variable retention harvesting based on a combination of aggregate patches and dispersed retention during the last 18 years comparing with other silviculture proposals(e.g.,shelterwood cuts)and control treatments(primary unmanaged forests).We summarized the results for(i)sawmill operations,(ii)timber yield,(iii)overstory stability,(iv)forest structure,(v)microclimate and natural cycles,(vi)natural regeneration dynamics(flowering,seeding,foraging,recruitment,growth,and mortality),and(vii)biodiversity(mammals,understory plants,mistletoes,birds,arthropods,mosses,lichens,and fungi).In general,aggregate patches maintained forest structure and micro-environmental variables,and slightly increased biodiversity and forest reproduction variables compared to unmanaged primary *** the contrary,dispersed retention decreased forest structure variables and greatly increased biodiversity(richness and abundance)when it was compared to unmanaged primary *** conditions are influenced by variable retention harvesting,but direction and magnitude of the effect depend and differ according to retention *** this,biodiversity taxa greatly differed among groups depending on retention *** general,the species assemblages in aggregate patches were similar to those found in primary unmanaged forests,while they were significantly modified in the dispersed *** occurred due to(i)local extinction of some original species,(ii)the introduction of native species from the surrounding environments,or(iii)the invasion of exotic *** silvicultural method has been a useful tool to conserve biodiversity and ec

关键词： Aggregate patches Dispersed retention Biodiversity conservation Long-term sustainability Timber production

Design on a multi-Sensor Integrated Attitude Determination System for Small UAVs

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Journal of Harbin Institute of Technology(New Series) 2014年第6期21卷 81-92页

作者： Cun-Xiao miao juan-juan Cao Jian-Cheng Fang School of mechanical Engineering University of Science and Technology Beijing Science and Technology on Space Physics Laboratory School of Instrumentation Science and Optoelectronics Engineering Beihang University

This paper discusses the design and implementation of a low cost multi-sensor integrated attitude determination system for small unmanned aerial vehicles( UAVs),which uses strapdown inertial navigation system( SINS) based on micro electromechanical system( mEmS) inertial sensors,commercial GPS receiver,and 3-axis ***-SINS initial attitude determination cannot be well performed for the reason that the mEmS inertial sensors biases are time-varying and poor repeatability,therefore in this paper the magnetometer and inclinometer are used to assist the mEmS-SINS initial attitude determination and mEmS inertial sensors field ***,the attitude determination algorithms are presented to estimate the full attitude during GPS signal outage and non-accelerating ***,the attitude information estimation results are compared with the reference of the non-magnetic marble platform and 3-axis *** the attitude estimation precision satisfies the requirement of attitude measurement for small UAVs during GPS signal outage and ***,the small UAV autonomous flight test results show that the low cost and real-time attitude determination system can yield continuous,reliable and effective attitude information for small UAVs.

关键词： attitude determination micro electromechanical system(mEmS) global positioning system(GPS) magnetometer small UAV