45 research outputs found

    The distribution of pond snail communities across a landscape: separating out the influence of spatial position from local habitat quality for ponds in south-east Northumberland, UK

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    Ponds support a rich biodiversity because the heterogeneity of individual ponds creates, at the landscape scale, a diversity of habitats for wildlife. The distribution of pond animals and plants will be influenced by both the local conditions within a pond and the spatial distribution of ponds across the landscape. Separating out the local from the spatial is difficult because the two are often linked. Pond snails are likely to be affected by both local conditions, e.g. water hardness, and spatial patterns, e.g. distance between ponds, but studies of snail communities struggle distinguishing between the two. In this study, communities of snails were recorded from 52 ponds in a biogeographically coherent landscape in north-east England. The distribution of snail communities was compared to local environments characterised by the macrophyte communities within each pond and to the spatial pattern of ponds throughout the landscape. Mantel tests were used to partial out the local versus the landscape respective influences. Snail communities became more similar in ponds that were closer together and in ponds with similar macrophyte communities as both the local and the landscape scale were important for this group of animals. Data were collected from several types of ponds, including those created on nature reserves specifically for wildlife, old field ponds (at least 150 years old) primarily created for watering livestock and subsidence ponds outside protected areas or amongst coastal dunes. No one pond type supported all the species. Larger, deeper ponds on nature reserves had the highest numbers of species within individual ponds but shallow, temporary sites on farm land supported a distinct temporary water fauna. The conservation of pond snails in this region requires a diversity of pond types rather than one idealised type and ponds scattered throughout the area at a variety of sites, not just concentrated on nature reserves

    Optimization of the Strength-Fracture Toughness Relation in Particulate-Reinforced Aluminum Composites via Control of the Matrix Microstructure

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    The article of record as published may be found at http://dx.doi.org/10.1007/s11661-998-0119-9The evolution of the microstructure and mechanical properties of a 17.5 vol. pct SiC particulatereinforced aluminum alloy 6092-matrix composite has been studied as a function of postfabrication processing and heat treatment. It is demonstrated that, by the control of particulate distribution, matrix grain, and substructure and of the matrix precipitate state, the strength-toughness combination in the composite can be optimized over a wide range of properties, without resorting to unstable, underaged (UA) matrix microstructures, which are usually deemed necessary to produce a higher fracture toughness than that displayed in the peak-aged condition. Further, it is demonstrated that, following an appropriate combination of thermomechanical processing and unconventional heat treatment, the composite may possess better stiffness, strength, and fracture toughness than a similar unreinforced alloy. In the high- and low-strength matrix microstructural conditions, the matrix grain and substructure were found to play a substantial role in determining fracture properties. However, in the intermediate- strength regime, properties appeared to be optimizable by the utilization of heat treatments only. These observations are rationalized on the basis of current understanding of the grain size dependence of fracture toughness and the detailed microstructural features resulting from thermomechanical treatments.United States Army Research OfficeArmy Research LabratoryUnited States Air Force Office of Scientific ResearchWright Materials LabratoryDWA Composite

    Prognostic Value of Podoplanin Expression in Oral Squamous Cell Carcinoma鈥旳 Regression Model Auxiliary to UICC Classification

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    Podoplanin, a type I transmembrane glycoprotein with an effect of platelet aggregation, has been reported to be one of the possible prognostic factors of oral squamous cell carcinoma (OSCC). However, the biological significance of podoplanin is largely unclear. The aim of this study was to develop a practical model for the prediction of prognosis using the grade of podoplanin expression, and also to evaluate the biological function of podoplanin. Eighty-two specimens of patients with previously untreated OSCC, who underwent either biopsy or surgery, were histopathologically and immunohistochemically analyzed. These 82 cases were composed of 66 well-differentiated, 10 moderately differentiated and 6 poorly differentiated OSCC. Podoplanin was successfully immunostained in 78 specimens, and was detected in most cases, but the frequency of positive cells varied. The prognosis of patients with more than 50 % podoplanin-positive tumor cells was significantly poorer than that of the other patients. Multivariate hazards regression analysis suggested that a linear combination of covariates, OSCC patients with more or less than 50 % podoplanin expression, age of more or less than 70 years old, mode of invasion and T3, T4 or T2 versus T1 of the UICC T-stage classification was the most effective model for evaluating the prognosis of OSCC patients. Additionally, podoplanin expression had a significant relationship to UICC clinical stage and the expression of Ki-67. An effective regression model using podoplanin expression was developed for evaluating the prognosis of OSCC and the biological significance of podoplanin was suggested to be associated with the growth and/or progression of OSCC

    Analysis of the impact of sex and age on the variation in the prevalence of antinuclear autoantibodies in Polish population: a nationwide observational, cross-sectional study

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    The detection of antinuclear autoantibody (ANA) is dependent on many factors and varies between the populations. The aim of the study was first to assess the prevalence of ANA in the Polish adult population depending on age, sex and the cutoff threshold used for the results obtained. Second, we estimated the occurrence of individual types of ANA-staining patterns. We tested 1731 patient samples using commercially available IIFA using two cutoff thresholds of 1:100 and 1:160. We found ANA in 260 participants (15.0%), but the percentage of positive results strongly depended on the cutoff level. For a cutoff threshold 1:100, the positive population was 19.5% and for the 1:160 cutoff threshold, it was 11.7%. The most prevalent ANA-staining pattern was AC-2 Dense Fine speckled (50%), followed by AC-21 Reticular/AMA (14.38%) ANA more common in women (72%); 64% of ANA-positive patients were over 50 years of age. ANA prevalence in the Polish population is at a level observed in other highly developed countries and is more prevalent in women and elderly individuals. To reduce the number of positive results released, we suggest that Polish laboratories should set 1:160 as the cutoff threshold

    The Robotic Bar -- An Integrated Demonstration of Man-Robot Interaction in a Service Scenario

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    Coming out of the labs, the first robots are currently appearing on the consumer market. Initially they target rather simple application scenarios ranging from entertainment to home convenience. However, one can expect, that they will capture more complex areas soon. These robots will collaborate and interactively communicate with their human users. All this does require appropriate manmachine interaction technologies and considerable cognitive abilities on the robot's side. Consumer acceptance will strongly depend on the integrated system. Thus, system integration and evaluation of the integrated system become increasingly important. This paper describes our approach to construct a robotic assistance system. We present experience with an integrated technology demonstration and the exposure of the integrated system to the public

    Management of the national administration of water from 2018

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    Podj臋to pr贸b臋 analizy zarz膮dzania krajow膮 gospodark膮 wodn膮 od 2018 roku w Polsce. Przeanalizowano ustaw臋 Prawo wodne, kt贸ra zacz臋艂a obowi膮zywa膰 od 20 lipca 2017 roku. Przedstawiono zmiany w zakresie praw i obowi膮zk贸w zwierzchnika w stosunku do w贸d publicznych stanowi膮cych w艂asno艣膰 skarbu pa艅stw oraz por贸wnano obowi膮zuj膮c膮 ustaw臋 z ustaw膮 z 18 lipca 2001 roku. Przedstawiono instytucj臋 Pa艅stwowego Gospodarstwa Wodnego Wody Polskie oraz jej hierarchi臋 i zakres obowi膮zk贸w, a tak偶e dokumenty przez ni膮 wydawane.An attempt was made to analyze the management f domestic water management since 2018 in Poland. The New Water Law, which became effective from 20 July 2017, has been analyzed. Changes in the scope of rights and duties of the superior in relation to public waters owned by the State Treasury were presented and the binding Act was compared to the Act of July 18, 2001. The institution of the State Aquatic Water Poland and its hierarchy and scope of duties was presented. The documents that are issued by the new institution are also specified

    The penetration of topically applied ointment containing hyaluronic acid in rabbit tissues

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    The properties of hyaluronic acid used for treatment of acute and chronic joint disease are known for many years and this compound is widely used both in humans and animals. To obtain a therapeutic effect of a certain drug, the appropriate concentration in the target organ or tissue is important. The application of labeled compounds is one of the frequently applied techniques to estimate drug penetration into the skin and other body tissues or organs. The aim of the study was to evaluate the penetration of hyaluronic acid labeled with I-131 through the skin and its distribution within the knee joint and other internal organs in rabbits after a topical application of an ointment containing hyaluronic acid.The experiment was performed on 22 albino rabbits divided into control and examined groups. Fifteen rabbits were exposed to the multicomponent ointment containing hyaluronic acid labeled with I-131. Time of exposure was 48 hours. Hyaluronate penetrated to a high degree into the examined tissues. No significant differences in terms of leg tissue activity were observed between a leg tissue exposed to labeled ointment and that unexposed, suggesting that after topical administration, the active component of the ointment is delivered to the joint via the blood stream. Hyaluronate applied topically penetrates through the skin into the rabbit tissues and organs and into the joint fluid of both legs (exposed and not exposed). This route of administration seems to be useful for this drug delivery and allows to avoid unnecessary side effects
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