Genetic structure of cherry fruit fly (Rhagoletis cingulata) populations across managed,unmanaged, and natural habitats

The cherry fruit fly (CFF), Rhagoletis cingulata Loew (Diptera: Tephritidae: Trypetini), is endemic to eastern North America and Mexico, where its primary native host is black cherry [Prunus serotina Ehrh. (Rosaceae)]. Cherry fruit fly is also a major economic pest of the fruit of cultivated sweet (Prunus avium L.) and tart (Prunus cerasus L.) cherries. Adult CFF that attack wild black cherry and introduced, domesticated cherries in commercial and abandoned orchards are active at different times of the summer, potentially generating allochronic isolation that could genetically differentiate native from sweet and tart CFF populations. Here, we test for host‐related genetic differences among CFF populations in Michigan attacking cherries in managed, unmanaged, and native habitats by scoring flies for 10 microsatellite loci. Little evidence for genetic differentiation was found across the three habitats or between the northern and southern Michigan CFF populations surveyed in the study. Local gene flow between native black cherry, commercial, and abandoned orchards may therefore be sufficient to overcome seasonal differences in adult CFF activity and prevent differentiation for microsatellites not directly associated with (tightly linked to) genes affecting eclosion time. The results do not support the existence of host‐associated races in CFF and imply that flies attacking native, managed, and unmanaged cherries should be considered to represent a single population for pest management purposes.     

阻生牙拔除术的临床进展

阻生牙是指由于各种阻力导致不能正常萌出的牙齿的统称,通常阻生牙牙体大部甚至全部埋伏于骨内。阻生牙可导致各种并发症的发生,因此临床上一般主张预防性拔除阻生牙。阻生牙拔除手术因其难度高、风险大、术后反应重一直是口腔牙槽外科关注的重点。近年来随着手术器械、手术观念等方面的进步,阻生牙拔除术取得了一些临床进展。新型CT扫描设备CBCT可以为手术设计提供精确定位;借助各类微创器械,微创拔牙技术减小了手术创伤,降低了手术风险;新型麻醉方式和新型局麻药物可以极大减轻疼痛反应;心理干预也将成为阻生牙拔除患者围手术期管理的重要步骤。本文对近年来阻生牙拔除术在定位方式、微创技术、团队协作、疼痛控制和心理干预等方面的临床进展做一综述。     

The influence of biomanipulation on fish community development in a southeastern United States cooling reservoir

L Lake, a reactor cooling reservoir in South Carolina, USA was managed after filling to promote the development of healthy ecological communities similar to those in mature regional cooling reservoirs. Two types of biomanipulation were undertaken to achieve this goal, the introduction of typical southeastern US reservoir fishes (bluegill and largemouth bass) and artificial planting of native aquatic macrophytes. Fish assemblages were monitored by electrofishing from reservoir filling in 1986 until 1998. Multivariate analysis divided the fish samples into five sequential periods resulting from species replacements and additions. Small species that colonized L Lake from a feeder stream predominated in the first period but were mostly eliminated, as bluegill, largemouth bass, and other lentic species increased in the second period. A rapid increase in threadfin shad abundance characterized the third period, and small littoral zone and phytophilous fishes increased during the fourth and fifth periods coincident with the proliferation of aquatic macrophytes. Analysis of Bray-Curtis similarities and the species accumulation rate indicated that the rate of fish community change decreased with time and that fish community structure changed little during the last several years of the study. By the end of the study, community structure was similar to that in a nearby cooling reservoir that supported diverse and resilient biota. Biomanipulation contributed to the rapid establishment of lentic species and later increases in small littoral and phytophilous species suggesting that biomanipulation may be useful in accelerating fish community development in new cooling reservoirs.     

孝感城区中老年对慢性病及社区管理现状认知情况的调查研究

目的:调查孝感城区中老年对慢性病及其社区管理现状认知情况。方法:选择2010年7月至2015年7月在孝感城区3个社区的500名中老年人作为研究对象,利用自拟调查问卷对所有受试者进行数据调查,分析孝感城区中老年对慢性病的认知情况,及对慢性病社区管理现状的认知情况,分析影响慢性病认知的因素。结果:在慢性病种类中,孝感城区中老年人对于高血压和糖尿病,及风湿性关节炎与慢性支气管炎的认知率较高,而对于癌症、偏瘫及血栓的认知率较低,差异有统计学意义(P0.05)。在慢性病的危险因素中,孝感城区中老年人对于缺乏锻炼、吸烟及膳食不合理的认知率明显较高,而对于酗酒、缺乏保健知识及悲观情绪的认知率明显较低,差异有统计学意义(P0.05)。在慢性病社区管理现状上,孝感城区中老年对于指导其改变生活习惯的认知率较高,为62.00%,而在进行三级预防、强化慢性病自我管理、定期举办慢性病专题讲座以及建立社区卫生的信息服务平台等方面的认知率明显较低,分别为22.40%、36.80%、42.20%及21.80%,差异有统计学意义(P0.05)。Logistic分析显示,文化程度低、经济收入低、未患慢性病及年龄≥60岁均为慢性病认知的危险因素。结论:孝感城区中老年对慢性病及其社区管理现状认知仍存在一定的不足,相关社区卫生管理部门应针对问题的影响因素,积极采取措施,改善社区管理现状。     

Models for forest ecosystem management: a European perspective

BACKGROUND: Forest management in Europe is committed to sustainability. In the face of climate change and accompanying risks, however, planning in order to achieve this aim becomes increasingly challenging, underlining the need for new and innovative methods. Models potentially integrate a wide range of system knowledge and present scenarios of variables important for any management decision. In the past, however, model development has mainly focused on specific purposes whereas today we are increasingly aware of the need for the whole range of information that can be provided by models. It is therefore assumed helpful to review the various approaches that are available for specific tasks and to discuss how they can be used for future management strategies. SCOPE: Here we develop a concept for the role of models in forest ecosystem management based on historical analyses. Five paradigms of forest management are identified: (1) multiple uses, (2) dominant use, (3) environmentally sensitive multiple uses, (4) full ecosystem approach and (5) eco-regional perspective. An overview of model approaches is given that is dedicated to this purpose and to developments of different kinds of approaches. It is discussed how these models can contribute to goal setting, decision support and development of guidelines for forestry operations. Furthermore, it is shown how scenario analysis, including stand and landscape visualization, can be used to depict alternatives, make long-term consequences of different options transparent, and ease participation of different stakeholder groups and education. CONCLUSIONS: In our opinion, the current challenge of forest ecosystem management in Europe is to integrate system knowledge from different temporal and spatial scales and from various disciplines. For this purpose, using a set of models with different focus that can be selected from a kind of toolbox according to particular needs is more promising than developing one overarching model, covering ecological, production and landscape issues equally well.     

The contrasting effects of short‐ and long‐term habitat drainage on the population dynamics of freshwater turtles in a human‐dominated landscape

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南亚热带10种造林树种的水力结构和水力安全

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Cattle grazing in CRP grasslands during the nesting season: effects on avian abundance and diversity

The Conservation Reserve Program (CRP) is a primary tool for restoring grassland in the United States, in part as wildlife habitat, which has benefited declining grassland bird populations. Among potential mid-contract management practices used to maintain early-successional CRP grasslands, cattle grazing had been prohibited and is currently disincentivized during the primary nesting season for birds (much of the growing season), despite the important role that large herbivores historically played in structuring grassland ecosystems. Conservative grazing of CRP grasslands could increase spatial heterogeneity in vegetation structure and plant diversity, potentially supporting higher densities of some grassland bird species and higher bird diversity. Our objective was to determine the effect of experimental cattle grazing on species-specific relative abundance and occupancy, species diversity, and community dissimilarity of grassland birds on CRP grasslands across the longitudinal extent of Kansas, USA (a 63.5-cm precipitation gradient) during the 2017–2019 avian breeding seasons. Fifty-three of 108 fields were grazed by cattle during the growing seasons of 2017 and 2018 and all fields were rested from grazing in 2019. For all analyses, we examined separate model sets for semiarid western versus more mesic eastern Kansas. Using data from line transect surveys, we modeled relative abundances of 5 songbird species: grasshopper sparrow (Ammodramus savannarum), dickcissel (Spiza americana), eastern meadowlark (Sturnella magna), western meadowlark (Sturnella neglecta), and brown-headed cowbird (Molothrus ater). Grazing had delayed yet positive effects on abundances of grasshopper sparrow in western Kansas, and eastern meadowlark in eastern Kansas, but negative effects on dickcissel abundance in western Kansas and especially on burned fields in eastern Kansas. Somewhat counterintuitively, brown-headed cowbirds in western Kansas were more abundant on ungrazed versus grazed fields in the years after grazing began. In addition, we modeled multi-season occupancy of 3 gamebird species (ring-necked pheasant [Phasianus colcicus], northern bobwhite [Colinus virginianus], mourning dove [Zenaida macroura]) and Henslow's sparrow (Centronyx henslowii); grazing did not affect occupancy of these species. In eastern Kansas, species diversity was highest in grazed, unburned fields. In western Kansas, bird communities in grazed and ungrazed fields were dissimilar, as determined from multivariate analysis. Though regionally variable, conservative stocking of cattle on CRP grasslands during the nesting season as a mid-contract management tool might increase bird species diversity by restructuring habitat that accommodates a greater variety of species and decreasing abundances of species associated with taller, denser stands of vegetation.     

Temporal variation and landcover influence survival in adult female mottled ducks

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