335 research outputs found
Comment: Plio‐Pleistocene Hominid limb proportions: evolutionary reversals or estimation errors?
Semantic web service architecture for simulation model reuse
COTS simulation packages (CSPs) have proved popular in an industrial setting with a number of software vendors. In contrast, options for re-using existing models seem more limited. Re-use of simulation component models by collaborating organizations is restricted by the same semantic issues however that restrict the inter-organization use of web services. The current representations of web components are predominantly syntactic in nature lacking the fundamental semantic underpinning required to support discovery on the emerging semantic web. Semantic models, in the form of ontology, utilized by web service discovery and deployment architecture provide one approach to support simulation model reuse. Semantic interoperation is achieved through the use of simulation component ontology to identify required components at varying levels of granularity (including both abstract and specialized components). Selected simulation components are loaded into a CSP, modified according to the requirements of the new model and executed. The paper presents the development of ontology, connector software and web service discovery architecture in order to understand how such ontology are created, maintained and subsequently used for simulation model reuse. The ontology is extracted from health service simulation - comprising hospitals and the National Blood Service. The ontology engineering framework and discovery architecture provide a novel approach to inter- organization simulation, uncovering domain semantics and adopting a less intrusive interface between participants. Although specific to CSPs the work has wider implications for the simulation community
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A Web Services Component Discovery and Deployment Architecture for Simulation Model Reuse
CSPs are widely used in industry, although have yet to operate across organizational boundaries. Reuse across organizations is restricted by the same semantic issues that restrict the inter-organization use of web services. The current representations of web components are predominantly syntactic in nature lacking the fundamental semantic underpinning required to support discovery on the emerging semantic web. Semantic models, in the form of ontology, utilized by web service discovery and deployment architecture provide one approach to support simulation model reuse. Semantic interoperation is achieved through the use of simulation component ontology to identify required components at varying levels of granularity (including both abstract and specialized components). Selected simulation components are loaded into a CSP, modified according to the requirements of the new model and executed. The paper presents the development carried out within CSPI-PDG and Fluidity Group at Brunel University, of an ontology, connector software and web service discovery architecture. The ontology is extracted from simulation scenarios involving airport, restaurant and kitchen service suppliers. The ontology engineering framework and discovery architecture provide a novel approach to inter-organization simulation, adopting a less intrusive interface between participants. Although specific to CSPs the work has wider implications for the simulation community
Fermi surface and order parameter driven vortex lattice structure transitions in twin-free YBa2Cu3O7
We report on small-angle neutron scattering studies of the intrinsic vortex
lattice (VL) structure in detwinned YBa2Cu3O7 at 2 K, and in fields up to 10.8
T. Because of the suppressed pinning to twin-domain boundaries, a new distorted
hexagonal VL structure phase is stabilized at intermediate fields. It is
separated from a low-field hexagonal phase of different orientation and
distortion by a first-order transition at 2.0(2) T that is probably driven by
Fermi surface effects. We argue that another first-order transition at 6.7(2)
T, into a rhombic structure with a distortion of opposite sign, marks a
crossover from a regime where Fermi surface anisotropy is dominant, to one
where the VL structure and distortion is controlled by the order-parameter
anisotropy.Comment: 4 pages, 3 figures (2 color), minor change
Population Structure of the Blue Crab Callinectes sapidus in the Maryland Coastal Bays
The population structure of the blue crab Callinectes sapidus was examined in the Maryland Coastal Bays (MCB) from 2014 to 2016. Crabs were sampled from April to December of each year. Size–frequency distributions showed a strong seasonal cycle, with small crabs being abundant in April, increasing in size through September, with adult crabs observed in the highest proportions from August through October of each year. A subsample of crabs was assayed for hemolymph ecdysone concentrations to examine molting patterns in field-collected blue crabs. Molting was observed throughout the sampling season, peaking in April for immature crabs, with lows in all size classes occurring in October. The mean size at maturity (L50) for females collected in this study was 116mmcarapace width (CW), which is comparable to that reported for the lower Chesapeake Bay (CB) and suggests crabs in the MCB are not significantly smaller as previously thought; however, large crabs (\u3e127 mmCW) appear to make up a smaller proportion of the total population in the MCB than in CB. Ovigerous females were observed at two distinct locations depending on the season, with 13/15 (86.7%) in southern Chincoteague Bay in April and May and 24/41 (58.5%) nearest to the Ocean City Inlet in July and August, indicating two potentially distinct spawning grounds and periods. This work suggests that blue crab reproductive success and general population trends are similar across both systems, with fishing pressure or disease in the MCB potentially explaining the low abundance of adult male crabs
A complex situation in data recovery
The research considers an unusual situation in data recovery. Data recovery is the process of recovering data from recording media that is not accessible by normal means. Providing that the data has not been overwritten or the recording medium physically damaged, this is usually a relatively simple process of either repairing the file system so that the file(s) may be accessed as usual or finding the data on the medium and copying it directly from the medium into normal file(s). The data in this recovery situation is recorded by specialist call centre recording equipment and is stored on the recording medium in a proprietary format whereby simultaneous conversations are multiplexed together and can only be accessed by using associated metadata records. The value of the recorded data may be very high especially in the financial sector where it may be considered a legal audit of business transactions. When a failure occurs and data needs to be recovered, both the data and metadata information must be recreated before a single call can be replayed. A key component to accessing this information is the location metadata that identifies the location of the required components on the medium. If the metadata is corrupted, incomplete or wrong then a repair cannot proceed until it is corrected. This research focuses on the problem of verifying this location metadata. Initially it was believed that only a small set of errors would exist and work centred on detecting these errors by presenting the information to engineers in an at-a-glance image. When the extent of the possible errors was realised, an attempt was made to deduce location metadata by exploring the content of the recorded medium. Although successful in one instance, the process was not able to distinguish between current and previous uses. Eventually insights gained from exploration of the recording application's source code, permitted an intelligent trial and error process which deduced the underlying medium apportioning formula. It was then possible to incorporate this formula into the heuristics, generating the at-a-glance image, to create an artefact that could verify the location metadata for any given repair. After discovering the formula, the research returned to the media exploration and the produced disk fingerprinting technique. The disk fingerprinting technique gave valuable insights into error states in call centre recording and provided a new way of seeing the contents of a hard drive. This research provided the following contributions: 1. It has provided a means by which the recording systems' location metadata can be verified and repaired. 2. As a result of this verification, greater automation of the recovery process is now possible before the need for human verification is required. 3. The disk fingerprinting process. This has already given insights into the recording system's problems and is able to provide a new way of seeing the contents of recording media.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
A framework for deriving semantic web services
Web service-based development represents an emerging approach for the development of distributed information systems. Web services have been mainly applied by software practitioners as a means to modularize system functionality that can be offered across a network (e.g., intranet and/or the Internet). Although web services have been
predominantly developed as a technical solution for integrating software systems, there is a more business-oriented aspect that developers and enterprises need to deal with in order to benefit from the full potential of web services in an electronic market. This ‘ignored’ aspect is the representation of the semantics underlying the services themselves as well as the ‘things’ that the services manage. Currently languages like the Web Services Description Language (WSDL) provide the syntactic means to describe web services, but
lack in providing a semantic underpinning. In order to harvest all the benefits of web services technology, a framework has been developed for deriving business semantics from syntactic descriptions of web services. The benefits of such a framework are two-fold. Firstly, the framework provides a way to gradually construct domain ontologies from previously defined technical services. Secondly, the framework enables the
migration of syntactically defined web services toward semantic web services. The study follows a design research approach which (1) identifies the problem area and its relevance from an industrial case study and previous research, (2) develops the
framework as a design artifact and (3) evaluates the application of the framework through a relevant scenario
Shared care obesity management in 3-10 year old children: 12 month outcomes of HopSCOTCH randomised trial
Objective: To determine whether general practice surveillance for childhood obesity, followed by obesity management across primary and tertiary care settings using a shared care model, improves body mass index and related outcomes in obese children aged 3-10 years. Design: Randomised controlled trial. Setting: 22 family practices (35 participating general practitioners) and a tertiary weight management service (three paediatricians, two dietitians) in Melbourne, Australia. Participants: Children aged 3-10 years with body mass index above the 95th centile recruited through their general practice between July 2009 and April 2010. Intervention: Children were randomly allocated to one tertiary appointment followed by up to 11 general practice consultations over one year, supported by shared care, web based software (intervention) or “usual care” (control). Researchers collecting outcome measurements, but not participants, were blinded to group assignment. Main outcome measures: Children’s body mass index z score (primary outcome), body fat percentage, waist circumference, physical activity, quality of diet, health related quality of life, self esteem, and body dissatisfaction and parents’ body mass index (all 15 months post-enrolment). Results: 118 (60 intervention, 56 control) children were recruited and 107 (91%) were retained and analysed (56 intervention, 51 control). All retained intervention children attended the tertiary appointment and their general practitioner for at least one (mean 3.5 (SD 2.5, range 1-11)) weight management consultation. At outcome, children in the two trial arms had similar body mass index (adjusted mean difference −0.1 (95% confidence interval −0.7 to 0.5; P=0.7)) and body mass index z score (−0.05 (−0.14 to 0.03); P=0.2). Similarly, no evidence was found of benefit or harm on any secondary outcome. Outcomes varied widely in the combined cohort (mean change in body mass index z score −0.20 (SD 0.25, range −0.97-0.47); 26% of children resolved from obese to overweight and 2% to normal weight. Conclusions: Although feasible, not harmful, and highly rated by both families and general practitioners, the shared care model of primary and tertiary care management did not lead to better body mass index or other outcomes for the intervention group compared with the control group. Improvements in body mass index in both groups highlight the value of untreated controls when determining efficacy.Melissa Wake, Kate Lycett, Susan A Clifford, Matthew A Sabin, Jane Gunn, Kay Gibbons, Cathy Hutton, Zoë McCallum, Sarah J Arnup, Gary Witter
Comparison of Handaxes from Bose Basin (China) and the Western Acheulean Indicates Convergence of Form, Not Cognitive Differences
Alleged differences between Palaeolithic assemblages from eastern Asia and the west have been the focus of controversial discussion for over half a century, most famously in terms of the so-called ‘Movius Line’. Recent discussion has centered on issues of comparability between handaxes from eastern Asian and ‘Acheulean’ examples from western portions of the Old World. Here, we present a multivariate morphometric analysis in order to more fully document how Mid-Pleistocene (i.e. ∼803 Kyr) handaxes from Bose Basin, China compare to examples from the west, as well as with additional (Mode 1) cores from across the Old World. Results show that handaxes from both the western Old World and Bose are significantly different from the Mode 1 cores, suggesting a gross comparability with regard to functionally-related form. Results also demonstrate overlap between the ranges of shape variation in Acheulean handaxes and those from Bose, demonstrating that neither raw material nor cognitive factors were an absolute impediment to Bose hominins in making comparable handaxe forms to their hominin kin west of the Movius Line. However, the shapes of western handaxes are different from the Bose examples to a statistically significant degree. Moreover, the handaxe assemblages from the western Old World are all more similar to each other than any individual assemblage is to the Bose handaxes. Variation in handaxe form is also comparatively high for the Bose material, consistent with suggestions that they represent an emergent, convergent instance of handaxe technology authored by Pleistocene hominins with cognitive capacities directly comparable to those of ‘Acheulean’ hominins
Effect of dietary potassium restriction on serum potassium, disease progression, and mortality in chronic kidney disease : a systematic review and meta-analysis
Low-potassium diets are recommended to reduce serum potassium (Sk) and prevent complications of chronic kidney disease (CKD), but evidence underpinning this recommendation has not been systematically reviewed and synthesized. We conducted a systematic review comparing change in Sk, CKD progression, and mortality between those on a low-potassium versus unrestricted potassium diet. We searched Medline, AMED, PsycINFO, CINAHL, Cochrane Central Register of Controlled Trials, and Clinicaltrials.org from inception to 3 April 2018. We included randomized and observational studies that compared these outcomes in adults with CKD who ate a restricted versus unrestricted amount of dietary potassium. We pooled mean change in Sk and adjusted hazard ratios of disease progression and mortality using random-effects meta-analyses. We identified 5,563 articles, of which seven studies (3,489 participants) met our inclusion criteria. We found very low-quality evidence that restricted (1,295 mg/d) versus unrestricted (1,570 mg/d) dietary potassium lowered Sk by -0.22 mEq/L (95% confidence interval [CI]: -0.33, -0.10; I = 0%). Lower (1,725 mg/d) versus higher (4,558 mg/d) dietary potassium was not significantly associated with disease progression (hazard ratio [HR]: 1.14; 95% CI: 0.77, 1.70; I = 57%). Lower (1,670 mg/d), compared with higher (4,414 mg/d) dietary potassium intake was associated with a 40% reduction in mortality hazard (HR: 0.60; 95% CI: 0.40, 0.89; I = 56%). Very-low-quality evidence supports consensus that dietary potassium restriction reduces Sk in normokalemia and is associated with a reduced risk of death in those with CKD. High-quality randomized controlled trials are needed. [Abstract copyright: Copyright © 2019 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
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