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Buzz-pollination in Neotropical bees:genus-dependent frequencies and lack of optimal frequency for pollen release

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Insect Science 2020年第1期27卷 133-142页

作者： conrado Augusto Rosi-Denadai Priscila cassia Souza Araujo Lucio Antonio de Oliveira campos Lirio cosme jr. Raul Narciso carvalho Guedes Departamento de Entomologia Universidade Federal de VigosaVigosaMinas GeraisBrazil Departamento de Biologia Geral Universidade Federal de VigosaVigosaMinas GeraisBrazil

Over 50 genera of bees release pollen from flower anthers using thoracic vibrations,a phenomenon known as *** efficiency of this process is directly affected by the mechanical properties of the buzzes,namely the duration,amplitude,and ***,although the effects of the former two properties are well described,the role of buzz frequency on pollen release remains ***,nearly all of the existing studies describing vibrational properties of natural buzz-pollination are limited to bumblebees(Bombus)and carpenter bees(Xvlocopa)constraining our current understanding of this behavior and its ***,we attempted to minimize this shortcoming by testing whether flower anthers exhibit optimal frequency for pollen release and whether bees tune their buzzes to match these(optimal)*** true,certain frequencies will trigger more pollen release and lighter bees will reach buzz frequencies closer to this optimum to compensate their smaller buzz *** strategies were used to test these hypotheses:(i)the use of(artificial)vibrational playbacks in a broad range of buzz frequencies and amplitudes to assess pollen release by tomato plants(Solarium Ivcopersicum L.)and(ii)the recording of natural buzzes of Neotropical bees visiting tomato plants during *** playback experiment indicates that although buzz frequency does affect pollen release,no optimal frequency exists for *** addition,the recorded results of natural buzz-pollination reveal that buzz frequencies vary with bee genera and are not correlated with body ***,neither bees nor plants are tuned to optimal pollen release *** frequency of buzz-pollination is a likely consequence of the insect flight machinery adapted to reach higher accelerations,while flower plant response to buzz-pollination is the likely result of its pollen granular properties.

关键词： buzz amplitude buzz frequency floral sonication pollination stingless bees vibration

A sensitive electrochemical detection of metronidazole in synthetic serum and urine samples using low-cost screen-printed electrodes modified with reduced graphene oxide and c60

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Journal of Pharmaceutical Analysis 2021年第5期11卷 646-652页

作者： Elsa Maria Materon Ademar Wong Tayane Aguiar Freitas Ronaldo censi Faria Osvaldo N.Oliveira jr. Department of chemistry Federal University of Sao Carlos13560-970Sao CarlosBrazil Sao carlos Institute of Physics University of Sao Paulo13560-970Sao CarlosBrazil

Monitoring the concentration of antibiotics in body fluids is essential to optimizing the therapy and minimizing the risk of bacteria resistance,which can be made with electrochemical sensors tailored with appropriate *** this paper,we report on sensors made with screen-printed electrodes(SPE)coated with fullerene(c60),reduced graphene oxide(rGO)and Nafion(NF)(c60-rGO-NF/SPE)to determine the antibiotic metronidazole(MTZ).Under optimized conditions,the c60-rGO-NF/SPE sensor exhibited a linear response in square wave voltammetry for MTZ concentrations from 2.5×10^(-7) to 34×10^(-6) mol/L,with a detection limit of 2.1×10^(-7) mol/*** sensor was also capable of detecting MTZ in serum and urine,with recovery between 94%and 100%,which are similar to those of the standard chromatographic method(HPLc-UV).Because the c60-rGO-NF/SPE sensor is amenable to mass production and allows for MTZ determination with simple principles of detection,it fulfills the requirements of therapeutic drug monitoring programs.

关键词： Metronidazole Fullerene Reduced graphene oxide Screen-printed electrodes Antibiotic

近地低速飞行时旋翼尾涡系的畸变及其诱导速度

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空气动力学学报 1989年第1期7卷 35-42页

作者：孙茂 H.c.curtiss jr. 北京航空航天大学美国普林斯顿大学

本文用一简化自由涡模型模拟旋翼尾涡系,用一简单涡模拟地面涡,对近地低速飞行时旋翼尾涡系的畸变及其引起的诱导速度变化作了研究。在地面涡和地面的影响下,桨盘附近的尾涡几何位置发生很大变化,导致桨盘处的诱导速度发生很大变化。尾... 详细信息

本文用一简化自由涡模型模拟旋翼尾涡系,用一简单涡模拟地面涡,对近地低速飞行时旋翼尾涡系的畸变及其引起的诱导速度变化作了研究。在地面涡和地面的影响下,桨盘附近的尾涡几何位置发生很大变化,导致桨盘处的诱导速度发生很大变化。尾涡畸变在桨盘处引起的诱导速度变化远远大于地面涡和地面在桨盘处直接产生的诱导速度。考虑尾涡畸变后计算出的诱导速度在桨盘处的分布和实验符合很好。

关键词：旋翼尾涡系畸变低速飞行

counting stripes:revision of the Lipinia vittigera complex(Reptilia, Squamata, Scincidae) with description of two new species from Indochina

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Zoological Research 2019年第5期40卷 358-393页

作者： Nikolay A. Poyarkov jr. Peter Geissler Vladislav A. Gorin Evgeniy A. Dunayev Timo Hartmann chatmongkon Suwannapoom Department of Vertebrate Zoology Biological Faculty Lomonosov Moscow State University Moscow 119991 Russia Joint Russian-Vietnamese Tropical Research and Technological center Nghia Do Cau Giay Hanoi Vietnam Museum Natur und Mensch Freiburg 79098 Germany Zoological Museum Moscow State University Moscow 125009 Russia Zoological Research Museum Alexander Koenig Bonn 53113 Germany School of Agriculture and Natural Resources University of Phayao Phayao 56000 Thailand

We provide an integrative taxonomic analysis of the Lipinia vittigera species complex from mainland Southeast Asia. Based on examination of external morphology, color pattern, and 681 base pairs of the cytochrome oxidase subunit I (cOI) mitochondrial gene, we demonstrate the presence of four morphologically distinct lineages of Lipinia in Vietnam, cambodia, Thailand, and Malaysia, showing a sequence divergence ranging 15.5%–20.4%. All discovered lineages are discretely diagnosable from one another by a combination of scalation traits and color patterns. A review of the published distribution data and a re-examination of available type material revealed the following results:(1) distribution of L. vittigera (Boulenger, 1894) sensu stricto is restricted to Sundaland and the Thai-Malay Peninsula south of the Isthmus of Kra;(2) L. microcercus (Boettger, 1901) stat. nov. is elevated to full species rank;the species has a wide distribution from central and southern Vietnam across cambodia to eastern Thailand;we regard Lygosoma vittigerum kronfanum Smith, 1922 and Leiolopisma pranensis cochran, 1930 as its junior synonyms;(3) Lipinia trivittata sp. nov. occurs in hilly areas of southern Vietnam, cambodia, and eastern Thailand;and (4) Lipinia vassilievi sp. nov. is currently known only from a narrow area along the Vietnamese-cambodian border in the foothills of the central Annamite Mountain Range. We further provide an identification key for Lipinia occurring in mainland Southeast Asia.

关键词： Lipinia microcercus stat. nov. Lipinia trivittata sp. nov. Lipinia vassilievi sp. nov. Vietnam, Thailand, cambodia Biogeography mtDNA cOI-barcoding

Development of a Procedure to Maximize Production of Hardy Rootstocks of citrus Using Stem cuttings

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American Journal of Plant Sciences 2017年第11期8卷 2837-2846页

作者： Richard c. Beeson jr. Dilma Silva University of Florida Institute of Food and Agricultural Science Mid-Florida Research and Education center Apopka USA Agromillora Florida Inc. Wildwood USA

Shoots of citrus sp. Kuharske were used to develop protocols for rooting reportedly HLB resistance rootstocks under intermittent mist. Investigated were shoot maturity, nodes per cutting, leaves per cutting, effects of buds, auxin concentrations and auxin solvent. Shoot maturity was most influential for success, with cuttings taken below the first 30 cm of active terminal growth producing greater root generation. Use of a thickening agent (Natrosal) to dilute the commercial auxin was second most in importance for rooting success. Root mass increased with increasing number of leaves. cutting stems between nodes or below the lowest bud were inconsequential. To produce maximum number of viable cuttings, single node-single leaf cuttings were preferred. Single bud cuttings produced one shoot after rooting. This was adventitious since multi-node cuttings usually sprouted new shoots that would need to be removed before budded. Evaluation of the best combination of auxin and cutting-related attributes were evaluated with four additional common rootstocks in June 2016. Rooting was 100% successful. A quick dip (0.5 s) in a 7500 ppm solution of Dip&Gro produced the most root generation in six weeks for all rootstocks. Root quantity varied by rootstock.

关键词： citrus Propagation Auxin concentration Stem Maturity cutting Length

Discovery of Japalura chapaensis Bourret,1937(Reptilia:Squamata:Agamidae)from Southeast Yunnan Province,china

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Zoological Research 2018年第2期39卷 105-113页

作者： Kai Wang Ke Jiang Yu-Fan Wang Nikolay A.Poyarkov jr. Jing che cameron D.Siler Sam Noble Oklahoma Museum of Natural History & Department of Biology University of Oklahoma Kunming Institute of Zoology Chinese Academy of Sciences Southeast Asia Biodiversity Research Institute Chinese Academy of Sciences Zhejiang Forest Resource Monitoring center Department of Vertebrate Zoology Biological Faculty Lomonosov Moscow State University

Due to a paucity of surveys in northern Indochina and lack of international collaborations among neighboring countries, recognized distributional ranges for many amphibian and reptile species end at the political borders for some countries, despite seemingly continuous suitable habitat spanning the region. combining both morphological and genetic data, we report the first discovery of Japalura chapaensis, a rare agamid lizard believed previously to be endemic to northern Vietnam only, along the border region of southeastern Yunnan Province,china. To facilitate future research on the genus Japalura sensu lato in Indochina, we provide detailed descriptions of additional specimens of this rare species, including the first description of coloration in life and an expanded diagnosis, and discuss the species boundary of J. chapaensis with respect to its congeners.

关键词： Draconinae Indochina Morphological Variation New record Range extension Systematics Taxonomy

Vivid birds do not initiate flight sooner despite their potential conspicuousness

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current Zoology 2015年第4期61卷 773-780页

作者： Nicholai M. HENSLEY Jonathan P. DRURY Theodore GARLAND, jr. Daniel T. BLUMSTEIN Department of Ecology Evolution and Marine Biology University of Califomia Santa Barbara CA USA Department of Ecology and Evolutionary Biology University of California Los Angeles CA 90095-1606 USA Institude de Biologie de I'ENS 46 Rue d'Ulm 75005 Paris France Department of Biology University of California Riverside CA 92521 USA

The distance from an approaching threat at which animals initiate flight - flight-initiation distance （FID） -- is a sensitive metric of variation in risk, but the effects on FID associated with the risk of possessing highly detectable external coloration are unknown. We tested whether variation in the degree of plumage vividness in birds explained variation in flight-initiation distance. After controlling for body mass, the distance at which the experimental approach began, and phylogenetic relatedness, plumage vividness was not a predictor of FID. contrary to the expectation that vividness affects risk, and therefore risk assess- ment, these results suggest that birds do not compensate for greater visual conspicuousness by fleeing sooner from approaching threats [current Zoology 61 （4）： 773-780, 2015].

关键词： Antipredator behavior Body size coloration comparative method conspicuousness Flight Initiation Distance

The Power of an Idea: The International Impacts of the Grand challenges for Engineering

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Engineering 2016年第1期2卷 4-7页

作者： c.D.Mote jr. Dame Ann Dowling 周济 US National Academy of Engineering (NAE) Royal Academy of Engineering (RAE) and Chinese Academy of Engineering (CAE)

Since the dawn of civilization, advances in the fields of engi- neering, science, and technology have played an indispensable role in shaping humans＇ social and economic development. Now people face a host of global ... 详细信息

关键词：国际工程工程科学经济发展人类社会

Selectively breeding for high voluntary physical activity in female mice does not bestow inherent characteristics that resemble eccentric remodeling of the heart,but the mini-muscle phenotype does

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Sports Medicine and Health Science 2023年第3期5卷 205-212页

作者： Eric c.Leszczynski Nicole E.Schwartz Ashley c.McPeek Katharine D.currie David P.Ferguson Theodore Garland jr. Department of Kinesiology Michigan State UniversityEast LansingMIUSA Department of Evolution Ecologyand Organismal BiologyUniversity of California RiversideRiversideCAUSA

Physical activity engagement results in a variety of positive health outcomes,including a reduction in cardiovascular disease risk partially due to eccentric remodeling of the *** purpose of this investigation was to determine if four replicate lines of High Runner mice that have been selectively bred for voluntary exercise on wheels have a cardiac phenotype that resembles the outcome of eccentric *** females(average age 55 days)from the 4 High Runner and 4 non-selected control lines were anaesthetized via vaporized isoflurane,then echocardiographic images were collected and analyzed for structural and functional *** Runner mice in general had lower ejection fractions compared to control mice lines(2-tailed p=0.0236)and tended to have thicker walls of the anterior portion of the left ventricle(p=0.065).However,a subset of the High Runner individuals,termed mini-muscle mice,had greater ejection fraction(p=0.0006),fractional shortening percentage(pcular mass at dissection(pcovariate)compared to non-mini muscle *** from replicate lines bred for high voluntary exercise did not all have inherent positive cardiac functional or structural characteristics,although a genetically unique subset of mini-muscle individuals did have greater functional cardiac characteristics,which in conjunction with their previously described peripheral aerobic enhancements(e.g.,increased capillarity)would partially account for their increased VO2max.

关键词： Echocardiography Heart Voluntary physical activity cardiovascular disease Wheel running