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First Successful Nesting of Black Oystercatchers among Endangered California Least Terns along the West Coast of North America
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作者 David L.Riensche Ben Pearl Susan Ramos 《Journal of Environmental Science and Engineering(A)》 2023年第3期100-105,共6页
A pair of Black Oystercatchers(Haematopus bachmani)established a nest in June 2022 at“Tern Town”,an island located in Hayward,California along the eastern side of the San Francisco Bay.This is the first documented o... A pair of Black Oystercatchers(Haematopus bachmani)established a nest in June 2022 at“Tern Town”,an island located in Hayward,California along the eastern side of the San Francisco Bay.This is the first documented occurrence of oystercatchers successfully nesting and fledgling young in association with California Least Terns.The island provides nesting habitat for three special status species.Since 2015,and for a total of six breeding seasons,the endangered California Least Tern(Sternula antillarum browni),the threatened Western Snowy Plover(Charadrius alexandrinus nivosus)and species-of-special-concern Black Skimmer(Rynchops niger),have nested successfully,in association with American Avocet(Recurvirostra americana)and Black-necked Stilt(Himantopus mexicanus).We collected shells near the oystercatcher nest to assess their diet.Diet data showed the oystercatchers foraged on,in decreasing order of abundance,Japanese Little-necked Clams(Ruditapes philippinarum),Ribbed Mussels(Geukensia demissa),Bent-nose Clams(Macoma nasuta),Limpets(Patellogastropoda sp.)and Bay Mussels(Mytilus edulis).This new report on breeding Black Oystercatchers indicates that managing habitat for California Least Tern,Western Snowy Plover,and Black Skimmer can also benefit Black Oystercatcher.This site-specific information on breeding Black Oystercatchers supports recovery plan tasks that are consistent with managing habitat for California Least Tern,Western Snowy Plover and Black Skimmer. 展开更多
关键词 Black Oystercatcher REPRODUCTION diet endangered species California Least tern Western Snowy Plover Black Skimmer
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Three Australian leg-flagged Roseate Terns found at Caiyu Archipelago of SE Fujian, China
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作者 林植 何芬奇 《Chinese Birds》 2012年第1期67-70,共4页
In undertaking regular surveys on those waterbirds appearing on Fujian coast and on offshore islands,people of Xiamen Bird-watching Society had observed,for five times during 2007-2009,three marked individuals of the ... In undertaking regular surveys on those waterbirds appearing on Fujian coast and on offshore islands,people of Xiamen Bird-watching Society had observed,for five times during 2007-2009,three marked individuals of the Roseate Tern (Sterna dougallii) on Caiyu Archipelago of south Fujian offshore; it is now quite certain that the leg-flags were marked on birds by people of the Australasian Wader Studies Group (AWSG) and at least one of those leg-flagged terns is already over six or seven years old by the time of re-sighting; this record might be useful and helpful for further estimating the life circle as well as the length of generation of those gulls and terns appearing and breeding along the SE Chinese coast,such as the Black-tailed Gull (Larus crassirostris),the Great Crested Tern (Sterna bergii),the Chinese Crested Tern (S.bernsteini),etc. 展开更多
关键词 Roseate tern Sterna dougallii found banded and leg-flagged Caiyu Archipelago southeast Fujian coast of SE China
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Assessing nest attentiveness of Common Terns via video cameras and temperature loggers
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作者 Jeffery D.Sullivan Paul R.Marbán +4 位作者 Jennifer M.Mullinax David F.Brinker Peter C.McGowan Carl R.Callahan Diann J.Prosser 《Avian Research》 CSCD 2020年第3期284-301,共18页
Background:While nest attentiveness plays a critical role in the reproductive success of avian species,nest attentiveness data with high temporal resolution is not available for many species.However,improvements in bo... Background:While nest attentiveness plays a critical role in the reproductive success of avian species,nest attentiveness data with high temporal resolution is not available for many species.However,improvements in both video monitoring and temperature logging devices present an opportunity to increase our understanding of this aspect of avian behavior.Methods:To investigate nest attentiveness behaviors and evaluate these technologies,we monitored 13 nests across two Common Tern(Sterna hirundo)breeding colonies with a paired video camera-temperature logger approach,while monitoring 63 additional nests with temperature loggers alone.Observations occurred from May to August of 2017 on Poplar(Chesapeake Bay,Maryland,USA)and Skimmer Islands(Isle of Wight Bay,Maryland,USA).We examined data respective to four times of day:Morning(civil dawn‒11:59),Peak(12:00‒16:00),Cooling(16:01‒civil dusk),and Night(civil dusk‒civil dawn).Results:While successful nests had mostly short duration off-bouts and maintained consistent nest attentiveness throughout the day,failed nests had dramatic reductions in nest attentiveness during the Cooling and Night periods(p<0.05)with one colony experiencing repeated nocturnal abandonment due to predation pressure from a Great Horned Owl(Bubo virginianus).Incubation appeared to ameliorate ambient temperatures during Night,as nests were significantly warmer during Night when birds were on versus off the nest(p<0.05).Meanwhile,off-bouts during the Peak period occurred during higher ambient temperatures,perhaps due to adults leaving the nest during the hottest periods to perform belly soaking.Unfortunately,temperature logger data alone had limited ability to predict nest attentiveness status during shorter bouts,with results highly dependent on time of day and bout duration.While our methods did not affect hatching success(p>0.05),video-monitored nests did have significantly lower clutch sizes(p<0.05).Conclusions:The paired use of iButtons and video cameras enabled a detailed description of the incubation behavior of COTE.However,while promising for future research,the logistical and potential biological complications involved in the use of these methods suggest that careful planning is needed before these devices are utilized to ensure data is collected in a safe and successful manner. 展开更多
关键词 Common tern IBUTTON Nest attentiveness Sterna hirundo Temperature logger Video monitoring
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Preliminary assessment on the current knowledge of the Chinese Crested Tern(Sterna bernsteini) 被引量:2
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作者 江航东 陈林 何芬奇 《Chinese Birds》 2010年第2期163-166,共4页
The Chinese Crested Tern (Sterna bernsteini;hereafter regarded as CCT, Plate I) is perhaps the most enigmatic tern bird in the world–though
关键词 Chinese Crested tern(Sterna bernsteini) current knowledge
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Latest evidence of the existence of the northern flock of the Chinese Crested Tern(Sterna bernsteini)
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作者 秦玉平 何芬奇 《Chinese Birds》 2011年第4期206-207,共2页
Three Chinese Crested Terns (Sterna bernsteini) were seen stopping at the Golden Coast of Rizhao (city), southern Shandong Province, China, on 6 September 2011. This is the third record of the bird appearing in northern
关键词 three Chinese Crested tern Rizhao of Shandong Province northern flock
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THE PATTERN OF GENERAL ATMOSPHERIC CIRCULATION IN EASTERN ASIA BEFORE THE UPLIFT OF THE TIBETAN PLATEAU
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作者 Jiang Xinsheng, Pan Zhongxi, Fu Qingping (Chengdu Institute of Geology and Mineral Resources,Chinese Academy of Geological Sciences, Chengdu 610082 , China) 《地学前缘》 EI CAS CSCD 2000年第S1期399-400,共2页
The global climatic change study is a hot point today.As the pattern of the general circulation of the atmosphere is the key factor for climate,the reconstruction of the pattern of the past general circulation of the ... The global climatic change study is a hot point today.As the pattern of the general circulation of the atmosphere is the key factor for climate,the reconstruction of the pattern of the past general circulation of the atmosphere has become important part of the global climatic change study.The paleowind belts are the comprising part of the past general circulation of the atmosphere and also the records of the circulation,therefore,their reconstruction will be helpful to the reconstruction of the general circulation of the atmosphere.In present years,the pattern of the general circulation of the atmosphere has attracted great concern from scientists.For example,Zhang Linyuan and Liu Dongsheng, based on the existence and inexistence of the Tibetan Plateau and paleogeography,divide the evolution of the general circulation of the atmosphere in eastern asia into two stages:the planetary wind stage before the uplift of the plateau and the monsoon stage after the uplift of the plateau which is subdivided into ancient monsoon and modern monsoon stages.While Dong Guangrong et al., Jiang Xinsheng et al. and Cooke et al, based on the latitudinal distribution of the Cretaceous and Tertiary deserts and the generation of arid climate,suggest that there was a subtropical high pressure zone across the eastern asia and was a planetary wind system,but have not found any direct record of the circulation.It is true that before the Early Tertiary,not only organism, but also inorganism,i.e.,biogeography and lithogeography, show strong zonal distribution.It can only indicate that zonal climate was evident at that time.Of course, as the climate is the result of the influences on the ground by zones of the circulation,it is reasonable to deduce the existence of zonal circulation,i.e. the the existence of the planetary wind system,from the zonal climate.But it would be much better if direct record of planetary wind system were found.Prevailing winds are the main geological agent for a desert which must leave deep stamps on the desert.The stamps on modern desert are reflected by dune migrating directions and on paleodesert by foreset dip directions..It is the most direct geological record for reconstructing paleowind belts and has been extensively used to reconstruct paleowind belts,paleogeography,paleoclimate and even to check the paleolatitude determined by paleomagnetism (for example, Opdyke and Runcorn, 1960; Creer, 1958; Pook, 1962; Bigarella and Salamuni,1961). 展开更多
关键词 CRETACEOUS deserts REGULARITY of paleowind DIRECTIONS pat tern of paleowind BELTS UPLIFT of the Tibet Plateau
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Abundance and prey capture success of Common Terns(Sterna hirundo)and Pied Kingfishers(Ceryle rudis)in relation to water clarity in south-east coastal Ghana
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作者 Lars H.Holbech Francis Gbogbo Timothy Khan Aikins 《Avian Research》 CSCD 2018年第3期226-238,共13页
Background: Water clarity may negatively influence rate of plunge diving and prey capture success of piscivorous plunge-diving birds, and therefore has implications for their conservation in polluted urban wetlands. W... Background: Water clarity may negatively influence rate of plunge diving and prey capture success of piscivorous plunge-diving birds, and therefore has implications for their conservation in polluted urban wetlands. We studied the relationship between water clarity and the abundance and prey capture success of Pied Kingfishers(Ceryle rudis) and Common Terns(Sterna hirundo) in two polluted coastal waters of south-east Ghana—the Weija Lake and Densu Delta Ramsar Site.Methods: On each wetland, data on abundance and prey capture success of plunge-divers were collected in four spatio-temporal quadrats of 100 m × 100 m and analysed with concurrent measurements of water quality parameters using GLM regression with Pearson's correlation coefficients.Results: Mean prey capture success of Pied Kingfishers(34.7 e two species responded differently to water clarity. The± 13.1%) and Common Terns(35.3 abundance of Common Terns was± 11.0%) were similar but th significantly higher in less transparent/more turbid water while that of Pied Kingfishers showed no significant relationship with turbidity and transparency. In contrast, the prey capture success of Common Terns was neither related to transparency nor turbidity, as opposed to that of Pied Kingfishers which was significantly higher in more turbid/less transparent waters. Correlations between capture success and bird abundance, as well as capture attempts were insignificant, suggesting that increased fish abundance associated with cloudy water may not necessarily promote higher abundance and capture success of foraging birds. Thus, when foraging in less transparent water, capture success may depend more on predator avoidance by fish prey than lower prey detectability of foraging birds.Conclusion: Within a gradient of 15–51 cm transparency studied, lower water clarity did not constrain prey capture success of Common Terns and Pied Kingfishers. Further studies on the foraging ecology of plunge-divers in coastal Ghana are however required to make firm conclusions on the relationship between water clarity and foraging birds and fish prey abundances, as well as capture success. 展开更多
关键词 Coastal Ghana Common tern PIED Kingfisher PREY capture SUCCESS Water TURBIDITY and transparency
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GPS tracking data reveal the annual spatiotemporal movement patterns of Bridled Terns
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作者 Xin Yu Ping Fan +3 位作者 Yun Wu Yongbin Chang Chenxi Jia Fumin Lei 《Avian Research》 SCIE CSCD 2022年第4期424-428,共5页
Understanding the spatiotemporal patterns of animal movement is a central theme in the growing field of movement ecology.The Bridled Tern(Onychoprion anaethetus)is widely distributed across tropical and subtropical la... Understanding the spatiotemporal patterns of animal movement is a central theme in the growing field of movement ecology.The Bridled Tern(Onychoprion anaethetus)is widely distributed across tropical and subtropical latitudes;however,knowledge of its annual movement is based only on relatively scarce recoveries of ringed birds.Studying the annual movement of pelagic seabirds is important to identify the impact of changes of marine habitats on them.We examined fine-scaled movement patterns of the species from two colonies in southern China by using GPS-GSM transmitters in 2018–2022.Twenty-three terns bred in Xichiyu Islet and Qilianyu Islet while wintered in four different sites:Gulf of Thailand,Natuna Islands,The Sulu Sea,and Makassar Strait.Bridled Terns made small detours and employed a fly-and-forage strategy with frequent stopovers to forage during autumn migration,but took more direct routes and reduced the need for stopovers during spring migration.Distance of migration between breeding and winter sites was significantly longer in autumn(average 3635 km)when compared with spring(2777 km).Ten birds with whole-year tracking data used the same breeding sites both years and four birds with tracking data of two consecutive years returned to the same wintering area,indicating that Bridled Terns are highly faithful to their breeding and wintering grounds. 展开更多
关键词 GPS-GSM Transmitters Bridled tern FIDELITY MIGRATION
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Breeding Habitat Use of Little Tern along Enshunada Coast-Tenryu River Continuum in Relation to Dam Development
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作者 Guangwei Huang 《Journal of Environmental Protection》 2015年第3期204-214,共11页
Breeding habitat of the Little Tern in a coast-river continuum was studied in relation to dam development. A habitat shift from coast to river occurred decades after dam construction as the dam-caused coastal erosion ... Breeding habitat of the Little Tern in a coast-river continuum was studied in relation to dam development. A habitat shift from coast to river occurred decades after dam construction as the dam-caused coastal erosion became manifested. On the other hand, the riverine habitat was affected by dam both positively and negatively. The positive aspect is the reduction of inundation risk for the habitat, and the negative effect is the vegetation development on the habitat. As a result, the bird did not abandon the riverine habitat although its physical characteristics may be considered as suboptimal. In addition, reasoning was given to explain why an artificially created habitat was not used by the bird. A general message resulting from this study is that species adaptive behaviors should be taken into consideration in assessing environmental impacts caused by human activities such as dam development. 展开更多
关键词 LITTLE tern RIVERINE HABITAT Coastal HABITAT DAM Erosion Vegetation
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Pair bonds during the annual cycle of a long-distance migrant,the Arctic Tern(Sterna paradisaea)
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作者 Chris P.F.Redfern 《Avian Research》 CSCD 2021年第3期346-353,共8页
Background:The extent to which pairs remain together during the annual cycle is a key question in the behav-ioural ecology of migratory birds.While a few species migrate and winter as family units,for most the extent ... Background:The extent to which pairs remain together during the annual cycle is a key question in the behav-ioural ecology of migratory birds.While a few species migrate and winter as family units,for most the extent to which breeding partners associate in the non-breeding season is unknown.The Arctic Tern(Sterna paradisaea)has one of the longest migrations of any species,and the aim of this study was to establish whether or not partners remain together after breeding.Methods:Leg-mounted geolocators were fitted to breeding pairs of Arctic Terns nesting on the Farne Islands,North-umberland,UK.The devices were recovered for analysis the following year.Results:Analysis of data for the six pairs which returned the following year showed that partners departed from the colony at different times after breeding and migrated independently to different Antarctic regions.Partners also departed from the Antarctic and turned to the breeding colony independently.One third of the pairs divorced on return.Conclusions:For long-distance migrants reliant on unpredictable foraging opportunities,it may not be viable to remain as pairs away from the breeding colony.Synchrony in arrival times at the breeding colony may maximise the chance of retaining a familiar partner,but could be affected by environmental factors in wintering areas or along migration routes. 展开更多
关键词 Arctic tern MIGRATION PAIR-BOND Partner association
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Hybrid Sooty Tern Optimization and Differential Evolution for Feature Selection
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作者 Heming Jia Yao Li +2 位作者 Kangjian Sun Ning Cao Helen Min Zhou 《Computer Systems Science & Engineering》 SCIE EI 2021年第12期321-335,共15页
In this paper,a hybrid model based on sooty tern optimization algo-rithm(STOA)is proposed to optimize the parameters of the support vector machine(SVM)and identify the best feature sets simultaneously.Feature selec-ti... In this paper,a hybrid model based on sooty tern optimization algo-rithm(STOA)is proposed to optimize the parameters of the support vector machine(SVM)and identify the best feature sets simultaneously.Feature selec-tion is an essential process of data preprocessing,and it aims to find the most rele-vant subset of features.In recent years,it has been applied in many practical domains of intelligent systems.The application of SVM in many fields has proved its effectiveness in classification tasks of various types.Its performance is mainly determined by the kernel type and its parameters.One of the most challenging process in machine learning is feature selection,intending to select effective and representative features.The main disadvantages of feature selection processes included in classical optimization algorithm are local optimal stagnation and slow convergence.Therefore,the hybrid model proposed in this paper merges the STOA and differential evolution(DE)to improve the search efficiency and con-vergence rate.A series of experiments are conducted on 12 datasets from the UCI repository to comprehensively and objectively evaluate the performance of the proposed method.The superiority of the proposed method is illustrated from dif-ferent aspects,such as the classification accuracy,convergence performance,reduced feature dimensionality,standard deviation(STD),and computation time. 展开更多
关键词 sooty tern optimization algorithm hybrid optimization feature selection support vector machine
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Biometrics and wing molt in White-winged Black Tern (Chlidonias leucopterus) in north-west Australia
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作者 Peter J. FULLAGAR Michael J. DAWKINS Clive D. T. MINTON 《Chinese Birds》 CSCD 2013年第4期306-313,共8页
We analyze morphometrics from a sample of 276 White-winged Black Tern(Chlidonias leucopterus) caught in north-west Australia on 4 March 2011. An estimated 40000 terns were present — the largest concentration of this ... We analyze morphometrics from a sample of 276 White-winged Black Tern(Chlidonias leucopterus) caught in north-west Australia on 4 March 2011. An estimated 40000 terns were present — the largest concentration of this species yet reported from Australia. When comparing juveniles with adults, only wing length and body mass differed significantly; however, juveniles were still easily recognized by plumage and wing molt as late as March. There was little evidence of any dramatic weight gain in adults before their northward migration. No morphological characteristic distinguishing sex was found. We confirmed that terns caught in this study did not appear to differ morphologically from those of the western palearctic populations. We describe wing molt based on data from 354 individuals captured and banded in Australia over 28 years. Wing molt proceeds in much the same way as found in other small terns. 展开更多
关键词 White-winged Black tern morphometrics wing molt AUSTRALIA feeding ROOSTING
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Breeding Status, Nesting Densities & Diet Trends of Two Endangered California Least Tern Colonies
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作者 David L. Riensche Meredith L. Elliott Susan H. Euing 《Journal of Environmental Science and Engineering(B)》 2012年第10期1135-1145,共11页
The California least tern (Sternula antillarum browni) is an endangered species. The two largest colonies of this bird species in the San Francisco Bay, California, USA, are located 23 km apart at Alameda Point and ... The California least tern (Sternula antillarum browni) is an endangered species. The two largest colonies of this bird species in the San Francisco Bay, California, USA, are located 23 km apart at Alameda Point and Hayward Regional Shoreline. The Alameda Point colony, on the former Naval Air Station, Alameda, has grown at an average rate of 9.2% per year since its discovery in 1976 and has a nesting density ranging from 1-153 nests per ha. Long-term breeding success at Alameda has averaged 0.86 fledglings per breeding pair. Least tems began appearing in 2003, at an island in Hayward enhanced with substrate mediums and social attraction devices. Successful breeding attempts have been observed at the Hayward colony since 2006. The Hayward colony has grown at an average rate of 51.5% per year, has a nesting density ranging from 33-333 nests per ha and long-term breeding success average of 0.87 fledglings per breeding pair. Dropped fish have been collected from both colonies, and silversides (family Atherinopsidae) are the dominant prey. Alameda terns forage on a greater variety of species than the Hayward terns. The regression results indicate the importance of Northern anchovy (Engraulis mordax) to the breeding success of the Alameda colony. 展开更多
关键词 California least tern endangered species breeding status nesting densities diet trends.
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Panda and Colorful Lan terns as the Highlights on China Festival in Moscow
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作者 He Xuan 《China & The World Cultural Exchange》 2019年第9期25-28,共4页
On September 13 to 15, a series of events of the two-day China Festival, dedicated to celebrate the 70^th anniversary of the founding of the People's Republic ot China and the establishment of China-Russia diploma... On September 13 to 15, a series of events of the two-day China Festival, dedicated to celebrate the 70^th anniversary of the founding of the People's Republic ot China and the establishment of China-Russia diplomatic relations.The China Festival was initiated by the Institute of Far Eastern Studies of the Russian Academy of Sciences and supported by the Embassy of the People's Republic of China in Russia, the Ministry of Culture and Tourism of the People's Republic of China, China Cultural Center in Moscow and other government bodies and organizations from both countries. 展开更多
关键词 PANDA COLORFUL LAN ternS Russian ACADEMY
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2005至2021年北京市海淀区60岁及以上老年人法定传染病流行特征及趋势分析
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作者 韦懿芸 孙亚敏 +1 位作者 鲁宁 朱玮燕 《传染病信息》 2024年第3期271-276,I0001-I0003,共9页
目的分析2005至2021年北京市海淀区60岁及以上老年人法定传染病发病水平和流行趋势,为老年人传染病防控提供依据。方法采用描述性分析、置换检验和秩和检验对疾病流行特征进行分析;应用Joinpoint回归(Joinpoint regression,JPR)模型计... 目的分析2005至2021年北京市海淀区60岁及以上老年人法定传染病发病水平和流行趋势,为老年人传染病防控提供依据。方法采用描述性分析、置换检验和秩和检验对疾病流行特征进行分析;应用Joinpoint回归(Joinpoint regression,JPR)模型计算年度变化百分比(annual percent change,APC)和平均年度变化百分比(average annual percent change,AAPC),对乙丙类传染病和重点传染病进行区间和全局流行趋势的分析。结果2005至2021年北京市海淀区老年人乙丙类传染病报告发病率为437.02/10万,报告死亡率为2.38/10万,报告病死率为0.54%。乙类传染病报告死亡率和病死率均高于丙类传染病(P均<0.01);男性老年人乙类传染病的发病率、死亡率和病死率均高于女性(P均<0.01);≥80岁组老年人各类传染病发病率、乙类传染死亡率最高(校正P均<0.05);乙类传染病报告发病率和报告死亡率的AAPC分别为-7.20(t=-7.802,P=0.000)和-5.31(t=-3.063,P=0.008)。报告发病率居前6位的传染病分别为其它感染性腹泻病(147.90/10万)、流行性感冒(82.32/10万)、痢疾(71.04/10万)、肺结核(54.56/10万)、隐性梅毒(25.43/10万)和乙肝(22.91/10万)。痢疾、乙肝和其它感染性腹泻病发病率AAPC分别为-12.79(t=-21.772,P=0.000)、-14.16(t=-4.672,P=0.000)和-10.61(t=-10.744,P=0.000),肺结核、流行性感冒发病率AAPC分别为1.15(t=2.977,P=0.009)和38.36(t=4.093,P=0.000);男性老年人肺结核、隐性梅毒、乙肝、其它感染性腹泻病和流行性感冒总体标准化发病率均高于女性。结论北京市海淀区老年人乙类传染病发病率和死亡率呈下降趋势;肺结核和流行性感冒是老年人群重点防控的传染病;肺结核和乙肝在男性老年人群中的流行不容忽视。 展开更多
关键词 法定传染病 流行趋势 老年人 Joinpoint回归模型
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Combining video and GPS-tracking to study the spatial foraging distribution of a single-prey loading seabird
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作者 Ruben C.Fijn Wouter Courtens +2 位作者 Bas W.R.Engels Emiel E.van Loon Judy Shamoun-Baranes 《Avian Research》 SCIE CSCD 2024年第3期316-325,共10页
Seabirds are valuable indicators of marine ecosystem processes and studying seabird diets can shed light on natural or human-induced variability in food-web composition.Specifically single-prey loading seabird species... Seabirds are valuable indicators of marine ecosystem processes and studying seabird diets can shed light on natural or human-induced variability in food-web composition.Specifically single-prey loading seabird species such as terns have the potential to act as visual sentinels of prey availability offshore.However,obtaining diet information from remote bird colonies is often challenging and time consuming.In this pilot study we present a novel approach to combine two established methods to study seabird foraging ecology,providing a powerful and cost-effective tool to study the distribution of prey items available to seabirds.We combined GPS tracking data of Sandwich Terns(Thalasseus sandvicensis)with prey-observations from a hide in 2012 and 2013,and from semicontinuously recorded camera footage in 2017.By doing so,we identified 115 approximate catch locations of prey(86 herring/sprat Clupeidae,29 sandeel Ammodytidae).Combining GPS-data and prey observations yielded detailed knowledge on the movements and chick diets of tracked birds as well as the spatial origin and lengths of captured prey items.Further catch distances of both Clupeidae and Ammodytidae resulted in deliveries of larger prey items and thus higher energy yield per trip,but also a higher energy expenditure per trip.We discuss the limitations and potential of our methodological approach to study foraging energetics during chick-provisioning of seabirds that carry prey items visible in their beaks. 展开更多
关键词 DIET Digitalfilm Geo-referencing Non-invasive monitoring PROVISIONING Sandwich tern Thalasseus sandvicensis
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疯狂自适应的正余弦乌燕鸥算法及应用
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作者 苏开拓 《机械设计与制造》 北大核心 2024年第7期65-71,共7页
桥式起重机主梁优化是一个非线性的复杂约束优化问题,现有方法求解此问题时存在收敛缓慢、稳定性差、收敛精度低等问题。为克服此问题,提出一种疯狂自适应的正余弦乌燕鸥混合优化算法(CCASSTOA)。在乌燕鸥算法(STOA)中,引入Logistics混... 桥式起重机主梁优化是一个非线性的复杂约束优化问题,现有方法求解此问题时存在收敛缓慢、稳定性差、收敛精度低等问题。为克服此问题,提出一种疯狂自适应的正余弦乌燕鸥混合优化算法(CCASSTOA)。在乌燕鸥算法(STOA)中,引入Logistics混沌映射对STOA算法种群初始化,增加种群个体的多样性和迭代初期收敛速度;将惯性自适应权重和正余弦算法混合搜索策略引入到乌燕鸥位置更新公式中,增强了算法的全局搜索与局部搜索之间的平衡能力。将疯狂算子引入到乌燕鸥最优位置进行扰动,增强迭代后期种群的多样性,避免算法陷入局部最优。采用6个测试函数对CCASSTOA算法性能进行验证,结果表明:CCASSTOA算法优于其他五种元启发式优化算法,收敛精度高,稳定性好和鲁棒性强。将CCASSTOA算法应用在32t/22.5m的桥式起重机主梁轻量化设计中,可实现主梁截面面积减小约为31.45%。因此,CCASSTOA算法可有效地处理此类非线性的约束优化问题。 展开更多
关键词 乌燕鸥算法 Logistics混沌映射 惯性自适应权重 正余弦算法 疯狂算子 桥式起重机主梁
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新发展格局下农产品流通系统构建思考
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作者 全春光 方子玲 +1 位作者 吴堪 叶欣 《物流技术》 2024年第2期1-8,共8页
梳理了2018年以来国内外在冷链物流、农产品批发市场、农产品品牌、现代化协同四个方面的研究热点,并立足于新发展格局的背景,深入剖析了农产品流通系统的发展现状;发现我国的农产品流通系统仍处于初级发展阶段,在生产、分配、流通和消... 梳理了2018年以来国内外在冷链物流、农产品批发市场、农产品品牌、现代化协同四个方面的研究热点,并立足于新发展格局的背景,深入剖析了农产品流通系统的发展现状;发现我国的农产品流通系统仍处于初级发展阶段,在生产、分配、流通和消费四个环节中面临着一系列亟待解决的问题。这些问题主要表现为冷链物流效益低下、品牌竞争力不强以及现代化协同程度较低等。针对这些问题,从冷链物流系统、农产品批发市场、农产品品牌和现代化水平等方面提出了农产品流通系统的发展对策,其重点在于利用现代化技术优化协同运作体系,构建农产品流通系统的协同创新模式,以提升农产品流通的效益和服务质量。 展开更多
关键词 农产品流通 流通模式 双循环 新发展格局 协同创新
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基于LE-ISTOA-SVM的聚合釜化工过程故障诊断
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作者 高淑芝 范策 《计算技术与自动化》 2024年第1期32-37,共6页
聚合釜是制备高分子化合物的最主要设备,其能否稳定的运行关系到产品的质量以及人员、设备的安全。但是,现代化工生产流程非常复杂,化工过程诊断数据具有高维非线性的特点。提出了基于LE-ISTOA-SVM的聚合釜化工过程故障诊断方法。首先,... 聚合釜是制备高分子化合物的最主要设备,其能否稳定的运行关系到产品的质量以及人员、设备的安全。但是,现代化工生产流程非常复杂,化工过程诊断数据具有高维非线性的特点。提出了基于LE-ISTOA-SVM的聚合釜化工过程故障诊断方法。首先,使用拉普拉斯特征映射算法(Laplace Feature Mapping Algorithm,LE)对故障数据进行降维。然后,使用改进乌燕鸥优化算法(Improved Sooty Tern Optimization Algorithm,ISTOA)优化SVM(Support Vector Machine,SVM)的参数来提高其性能。最后,利用聚合釜的实验数据做仿真测试。测试结果表明,该方法有较好的诊断效果。 展开更多
关键词 故障诊断 乌燕鸥优化算法 聚合釜
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低能冲击下复合材料蜂窝夹芯结构表面损伤分析
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作者 崔航 贾彩霞 李俊 《郑州航空工业管理学院学报》 2024年第4期29-33,44,共6页
基于低能量冲击探究复合材料蜂窝夹芯结构表面的损伤模式,分析低能量冲击对结构表面环氧树脂膜的裂纹扩展模式、损伤面积、裂纹长度和数量的影响,通过三点弯曲试验研究了低能冲击后碳纤维增强复合材料层合板的弯曲性能以及损伤极限值。... 基于低能量冲击探究复合材料蜂窝夹芯结构表面的损伤模式,分析低能量冲击对结构表面环氧树脂膜的裂纹扩展模式、损伤面积、裂纹长度和数量的影响,通过三点弯曲试验研究了低能冲击后碳纤维增强复合材料层合板的弯曲性能以及损伤极限值。研究结果表明,冲击能量会影响表面环氧树脂膜的损伤扩展模式,裂纹均以冲击落点为中心,向周围不规则地扩展,所形成的损伤面积随冲击能量递增,裂纹扩展长度与冲击能量成正相关,层合板的层间损伤模式以分层和纤维弯曲为主;低能量冲击试验证明了表面环氧树脂膜的裂纹扩展模式、损伤面积等与夹芯结构层合板内部的冲击损伤程度之间具备特定的联系,因此可为设计一种新的无损检测方法用于快速表征结构内部的冲击损伤提供可能性。 展开更多
关键词 环氧树脂膜 复合材料蜂窝夹芯结构 低能量冲击 表面损伤模式 三点弯曲
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