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Selected AbstractsSpatial population structure of a specialist leaf-mining mothJOURNAL OF ANIMAL ECOLOGY, Issue 4 2008Sofia Gripenberg Summary 1The spatial structure of natural populations may profoundly influence their dynamics. Depending on the frequency of movements among local populations and the consequent balance between local and regional population processes, earlier work has attempted to classify metapopulations into clear-cut categories, ranging from patchy populations to sets of remnant populations. In an alternative, dichotomous scheme, local populations have been classified as self-sustaining populations generating a surplus of individuals (sources) and those depending on immigration for persistence (sinks). 2In this paper, we describe the spatial population structure of the leaf-mining moth Tischeria ekebladella, a specialist herbivore of the pedunculate oak Quercus robur. We relate moth dispersal to the distribution of oaks on Wattkast, a small island (5 km2) off the south-western coast of Finland. 3We build a spatially realistic metapopulation model derived from assumptions concerning the behaviour of individual moths, and show that the model is able to explain part of the variation in observed patterns of occurrence and colonization. 4While the species was always present on large trees, a considerable proportion of the local populations associated with small oaks showed extinction,recolonization dynamics. The vast majority of moth individuals occur on large trees. 5According to model predictions, the dominance of local vs. regional processes in tree-specific moth dynamics varies drastically across the landscape. Most local populations may be defined broadly as ,sinks', as model simulations suggest that in the absence of immigration, only the largest oaks will sustain viable moth populations. Large trees in areas of high oak density will contribute most to the overall persistence of the metapopulation by acting as sources of moths colonizing other trees. 6No single ,metapopulation type' will suffice to describe the oak,moth system. Instead, our study supports the notion that real populations are often a mix of earlier identified categories. The level to which local populations may persist after landscape modification will vary across the landscape, and sweeping classifications of metapopulations into single categories will contribute little to understanding how individual local populations contribute to the overall persistence of the system. [source] DEFINING DYSKARYOSIS , THE BSCC CLASSIFICATION IN 2006CYTOPATHOLOGY, Issue 2006K. Denton The terminology used for reporting cervical samples in the UK is the BSCC classification, which has evolved over many years. In 2002 the BSCC held a consensus conference to review the BSCC classification, with the intention of providing clearer results for women, improving concordance with other terminologies and facilitating consistency with new scientific developments and technologies. The consensus conference was well attended and robust. In the intervening years there have also been other further advances on morphometry, data on outcomes, data from EQA and other sources. Liquid Based cytology (LBC) has been implemented by the NHS CSP. All of these developments have impacted on the proposed classification, which will be presented in full. The term ,dyskaryosis' will be retained and several of the current reporting categories will be relatively unchanged, though additional information on LBC will be provided. The major proposed changes are: (1) A move to a single category of ,High Grade Dyskaryosis' to replace the existing categories of moderate and severe dyskaryosis. (2) Sub-division of Borderline change into three categories. Borderline change in glandular cells Borderline change ?high grade Borderline change, NOS (3) The current grades of Mild Dyskaryosis and Borderline change with Koilocytosis to be merged. Details of these proposals, together with illustrations and the evidence base for change will be presented. [source] The Public Health Nursing Practice Manual: A Tool for Public Health NursesPUBLIC HEALTH NURSING, Issue 2 2004M.S.N./ M.P.H., Sharon D. Sakamoto R.N. Abstract Public health nursing is recognized as an important and critical component of the public health workforce, and today, it makes up the largest single category of public health professionals, according to the U.S. Department of Health and Human Services. Preparation of generalist public health nurses with the knowledge base, skills, and training to effectively respond to public health challenges is essential. The County of Los Angeles Department of Health Services, Public Health Nursing Section, in response to this need, implemented the Public Health Nursing Practice Manual to provide public health nurses with interventions and guidelines to articulate their role and practice as outlined by the framework of the Public Health Nursing Practice Model developed by Los Angeles County. Identification and development of new methods to support the practice of nursing is imperative in facilitating a more sophisticated and expanded level of practice, as well as providing a means of improving, protecting, and enhancing the quality of health for all people. The Public Health Nursing Practice Manual is an effective tool to monitor performance improvement and provide standardization of the generalist public health nurse practicing in Los Angeles County. [source] Classifying the fire-response traits of plants: How reliable are species-level classifications?AUSTRAL ECOLOGY, Issue 3 2010LYNDSEY MARIE VIVIAN Abstract Plant species in fire-prone environments possess specific traits which allow them to survive fire. Species are commonly classified according to whether they survive fire and resprout or whether they are killed by fire and regenerate from seed. However, different populations of the same species have been shown to vary in their responses. Therefore, the classification of a species into a single category based on fire-response traits may not necessarily be representative of every population under every circumstance. This study examined the extent of within-species variation in fire-response traits of woody plants in south-eastern Australia after the 2003 fires. Species were then classified using two approaches: (i) using data from a field survey of fire-response traits, taking into account within-species variation; and (ii) using species' fire responses listed in a pre-existing fire-response database compiled from a variety of primary sources. Field data showed that the majority of species in the study area resprouted after fire with around one in 10 species variable in their resprouting response. Almost half of all species varied from site to site according to whether they regenerated from seed, either solely or in addition to resprouting. The numbers of species classified as resprouters and seed regenerators varied according to the classification method used. Differences were also found between the classification method when calculating the mean proportion of resprouters and seed regenerators across sites. The fire-response traits for some species from the database were found to differ from the observed field responses. This study demonstrated that the application of a fire-response trait, reported in a trait database, to an entire species, may not adequately represent the actual fire responses of the populations of interest. Rather than considering the fire-response traits of a species, accurate prediction may be better achieved by considering how different populations of plants will respond to fire. [source] Acromioclavicular joint cyst formationCLINICAL ANATOMY, Issue 2 2010Andrew D. Hiller Abstract Acromioclavicular joint (ACJ) cysts are an uncommon and unusual sequela associated with shoulder pathophysiology. The majority of literature on ACJ cysts consists of individual case reports with no definitive literature review currently available. In addition to a comprehensive literature review, four clinical cases are presented in this report. First described by Craig (1984), a total of 41 cases have been previously reported in the literature. Of these cases, five occurred with the rotator cuff musculature intact. The remaining 36 cases of ACJ cysts occurred in patients with a complete tear/avulsion of the rotator cuff. Previous attempts at compiling a complete record of all reported cases have combined several distinct conditions into a single category. This article presents two distinct etiologies for the pathogenesis of ACJ cyst formation. In the presence of an intact rotator cuff, a Type 1 cyst can form superficially and be limited to the ACJ. Following a massive or traumatic tear of the rotator cuff, mechanical instability of the humeral head can cause a deterioration of the inferior acromioclavicular capsule (cuff tear arthropathy) and an overproduction of synovial fluid. Overtime, a "geyser" of fluid can form between the glenohumeral and the ACJ, forming a Type 2 cyst. This differentiation and categorization is essential for appropriate classification and treatment. Clin. Anat. 23:145,152, 2010. © 2010 Wiley-Liss, Inc. [source] |