679 research outputs found
Practice in Skills Designed to Improve Ability in Playing Handball
Practice sessions in the skill described in this paper were carried on by the writer during the months of January and February, 1939. The object of the practice sessions was to develop skill in handball, in which the subject had had no previous experience. Before deciding on the method of procedure, the subject observed several expert players. He then decided to practice along three lines which seemed most important in securing proficiency in the game
A Taxonomic and Ecological Study of Acridinae of Utah (Orthoptera-Locustidae)
Orthoptera, especially the family Locustidae, is one of the most important and most interesting orders of insects in the state of Utah. It includes a polyphagus group of great economic importance in the state. The topography and climate of Utah varies from forested alpine slopes to hot arid desert wastes, several life zones being represented. This great variation from desert to alpine in Utah presents a rather unique region for taxonomic and ecological studies of the Orthoptera. The most familiar representatives of the insect order Orthoptera are the long-horned grasshoppers, locusts, crickets, katydids, and cockroaches. Orthoptera are characterized by Comstock as those insects having mouth parts fitted for chewing, gradual metamorphosis, nymphal development terrestrial, with 2 pairs of wings or with wings bestigial or wanting. In winged forms the fore wings are more or less thickened, but have distinct venation; the hing wings, when at rest, are folded in plaits like a fan. The family Locustidae, called Acrididae by many authors, includes the locusts or short-horned grasshoppers, which are characterized by having short antennae, 3-jointed tarsi, and a short ovipositor in the female. The ovipositor has 4 separate spines and an egg guide for ovipositing. The 4 separate spines are used to penetrate the ground to a depth corresponding to the length of the abdomen. The eggs are then placed 1 at a time in regular order by the egg guide. During the process of egg-laying a fluid is secreted which hardens and binds the eggs together into a definite mass. The organs of hearing are situated on the first abdominal segment. There are 4 subfamilies of Locustidae. The Acrydiinae, commonly called pigmy locusts, have the pronotum extending over the entire dorsum of the abdomen; the claws of the tarsi have no arolium between them. The other 3 subfamilies have the pronotum extending, at most, only over the base of the abdomen, and the claws of the tarsi have an arolium between them. The Cyrtacanthacrinae (Locustinae), or spur-throated locusts, have the prosternum armed with a distinct conical tuberole. The Oedipodinae, or banded-winged locusts, lack the prosternal tubercle and have the head rounded at the union of the vertex and front. The Acridinae, commonly called slant-faced locusts, is the subfamily under consideration in this paper. The slant-faced locusts have a low median pronotal carina which is cut by one transverse sulcus; the front and vertex usually meet in an acute angle
Once a pond in time: employing palaeoecology to inform farmland pond restoration
The restoration of highly terrestrialized farmland ponds that combines the removal of woody vegetation and pond sediment greatly enhances aquatic biodiversity. Nonetheless, questions remain regarding the historical precedent of pond restoration, and particularly if post-restoration aquatic macrophyte communities resemble pre-terrestrialization assemblages. We used a paleoecological approach to address these questions for a typical, recently restored farmland pond in Norfolk, eastern England. Plant and animal remains in pond sediment cores were used to infer decadal-centennial scale changes to pond communities and to identify past pond management events. We then evaluated the resemblance of restored and historical assemblages by comparisons with contemporary post-restoration vegetation data. Based on changes in the abundance of terrestrial leaf remains and other indicators (increases followed by declines of aquatic organisms), the study pond appears to have a long history (going back to the early-1800s) of canopy management (at least three inferred management events), but after the mid-1970s, steady and substantial increases in terrestrial indicators, suggest cessation of management resulting in uninterrupted terrestrialization. Aquatic macrophyte communities arising after restoration showed some similarities with historical assemblages, but also contained apparently new species. This study demonstrates how paleolimnological methods can improve understanding of pond ecological histories to better inform restoration targets and practices. Implications for Practice Paleolimnological methods can be successfully employed at small, human-made ponds to assess past biological communities and trajectories of ecological change. Restoration of heavily terrestrialized farmland ponds through major woody vegetation and sediment removal mimics periodic management activities undertaken over past centuries and is essential to the maintenance of open canopy conditions and biodiversity conservation. Caution must be taken when setting restoration targets for farmland ponds as rare macrophyte species indicative of high water quality may not necessarily return to restored pond habitats due to fragmentation effects associated with the loss of local populations and/or in-pond eutrophication development
Open-canopy ponds benefit diurnal pollinator communities in an agricultural landscape: implications for farmland pond management
1. Declines in pollinating invertebrates across intensively cultivated landscapes linked to reductions in flower-rich habitats constitute a key threat to biodiversity conservation and the provision of ecosystem services. Over recent decades, many ponds in agricultural landscapes have become overgrown with woody vegetation, resulting in heavily shaded, flower-poor pond basins and margins. Restoration of farmland ponds through removal of sediment and encroaching woody vegetation (canopy management) from pond margins greatly enhances freshwater biodiversity. Nevertheless, the consequences of pond management for pond-margin plants and pollinating insects remain poorly understood. Here, we studied these effects for ponds in Norfolk, eastern England. 2. We compared richness, abundance and composition of pollinating insects (hymenopterans and syrphids) and insect-pollinated plant communities between open-canopy pond systems subjected to either (i) long-term regular management of woody vegetation or (ii) recent restoration by woody vegetation and sediment removal with those communities at (iii) ponds dominated by woody vegetation. 3. Canopy management increased the richness and abundance of pollinators and insect-pollinated plants. Pollinator richness and abundance was best explained by improvements in flower resources at open-canopy ponds. Management most strongly influenced hymenopteran communities. 4. Ponds represent important semi-natural habitats for insect-pollinated plant and pollinator communities in farmland. To enhance food resources, diversity and abundance of diurnal pollinators, conservation management at ponds should aim for mosaics of ponds at different successional stages with a high proportion of early successional open-canopy ponds. Agricultural ponds are emerging as important habitats not only for aquatic biodiversity, but also for terrestrial species, thus warranting their prioritisation in future agri-environment schemes
Using novel palaeolimnological techniques to define lake conservation objectives (Phase 1)
This is the final report to Natural England on Contract No: SAE03/02/054 ‘Using
novel palaeolimnological techniques to define lake conservation objectives’.
The primary objective of this project is to use existing and recently developed
palaeoecological techniques to define reference conditions and assess the condition
of selected SSSIs in England, and thereby to assist in the setting of conservation
objectives and management goals. The eight selected sites are Aqualate Mere,
Hawes Water (Silverdale), Cunswick Tarn, Over Water, Sunbiggin Tarn, Malham
Tarn, Semer Water and Hornsea Mere. The project is divided into four main tasks
with Task 1 essentially involving the collection, processing and dating of cores from
the study sites. To date only the latter has been funded and this report describes the
outputs of this task
Capturing accelerometer outputs in healthy volunteers under normal and simulated-pathological conditions using ML classifiers
Wearable devices offer a possible solution for acquiring objective measurements of physical activity. Most current algorithms are derived using data from healthy volunteers. It is unclear whether such algorithms are suitable in specific clinical scenarios, such as when an individual has altered gait. We hypothesized that algorithms trained on healthy population will result in less accurate results when tested in individuals with altered gait. We further hypothesized that algorithms trained on simulated-pathological gait would prove better at classifying abnormal activity.We studied healthy volunteers to assess whether activity classification accuracy differed for those with healthy and simulated-pathological conditions. Healthy participants (n=30) were recruited from the University of Leeds to perform nine predefined activities under healthy and simulated-pathological conditions. Activities were captured using a wrist-worn MOX accelerometer (Maastricht Instruments, NL). Data were analyzed based on the Activity-Recognition-Chain process. We trained a Neural-Network, Random-Forests, k-Nearest-Neighbors (k-NN), Support-Vector-Machines (SVM) and Naive Bayes models to classify activity. Algorithms were trained four times; once with 'healthy' data, and once with 'simulated-pathological data' for each of activity-type and activity-task classification. In activity-type instances, the SVM provided the best results; the accuracy was 98.4% when the algorithm was trained and then tested with unseen data from the same group of healthy individuals. Accuracy dropped to 52.8% when tested on simulated-pathological data. When the model was retrained with simulated-pathological data, prediction accuracy for the corresponding test set was 96.7%. Algorithms developed on healthy data are less accurate for pathological conditions. When evaluating pathological conditions, classifier algorithms developed using data from a target sub-population can restore accuracy to above 95%.Clinical Relevance - This method remotely establishes health-related data of objective outcome measures of activities of daily living
Integrating Habitats Directive and Water Framework Directive Monitoring: Baseline Survey of Natura 2000 Standing Water Habitats in Wales
This report was commissioned by the Environment Agency (EA) on behalf of the
Countryside Council for Wales (CCW) in 2004. It brings together data collected in 2003
and 2004 from 28 Welsh lakes in 11 Special Areas of Conservation (SACs).
The report
• collates and presents limnological data collected for the Environment Agency in
2003 for the purposes of site condition assessment,
• presents limnological data collected for CCW in 2004 for the purposes of site
condition assessment,
• provides a series of lake data reports on each of the 11 specifies SACs.
Sampling and analytical methods are described and the data presented in the report
include;
• site information (catchment geology, land use and lake characteristics and
bathymetries),
• water chemistry, temperature and oxygen profiles,
• macrophyte survey data presented as DAFOR rated species lists,
• short core analysis for diatoms (required for 19 of the 28 sites)
PPARα contributes to protection against metabolic and inflammatory derangements associated with acute kidney injury in experimental sepsis
Abstract Sepsis‐associated acute kidney injury (AKI) is a significant problem in critically ill children and adults resulting in increased morbidity and mortality. Fundamental mechanisms contributing to sepsis‐associated AKI are poorly understood. Previous research has demonstrated that peroxisome proliferator‐activated receptor α (PPARα) expression is associated with reduced organ system failure in sepsis. Using an experimental model of polymicrobial sepsis, we demonstrate that mice deficient in PPARα have worse kidney function, which is likely related to reduced fatty acid oxidation and increased inflammation. Ultrastructural evaluation with electron microscopy reveals that the proximal convoluted tubule is specifically injured in septic PPARα deficient mice. In this experimental group, serum metabolomic analysis reveals unanticipated metabolic derangements in tryptophan‐kynurenine‐NAD+ and pantothenate pathways. We also show that a subgroup of children with sepsis whose genome‐wide expression profiles are characterized by repression of the PPARα signaling pathway has increased incidence of severe AKI. These findings point toward interesting associations between sepsis‐associated AKI and PPARα‐driven fatty acid metabolism that merit further investigation
Two-axis bend measurement with Bragg gratings in multicore optical fiber
We describe what is to our knowledge the first use of fiber Bragg gratings written into three separate cores of a multicore fiber for two-axis curvature measurement. The gratings act as independent, but isothermal, fiber strain gauges for which local curvature determines the difference in strain between cores, permitting temperature-independent bend measurement. (C) 2003 Optical Society of America
Using a task-based approach in evaluating the usability of BoBIs in an e-book environment
This paper reports on a usability evaluation of BoBIs (Back-of-the-book Indexes) as searching and browsing tools in an e-book environment. This study employed a task-based approach and within-subject design. The retrieval performance of a BoBI was compared with a ToC and Full-Text Search tool in terms of their respective effectiveness and efficiency for finding information in e-books. The results demonstrated that a BoBI was significantly more efficient (faster) and useful compared to a ToC or Full-Text Search tool for finding information in an e-book environment
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