Recently, there has been an increasing interest in looking at urban environment as a complex system. More and more researchers are paying attention to the study of the configuration of urban space as well as human social activities within it. It has been found that correlation exists between the morphological properties of urban street network and observed human social movement patterns. This correlation implies that the influence of urban configurations on human social movements is no longer only revealed from the sense of metric distance, but also revealed from topological and geometrical perspectives. Metric distances, topological relationships and angular changes between streets should be considered when applying space syntax analysis to an urban street network. This thesis is mainly focused on the comparison among metric, topological and angular analyses based on three kinds of urban street representation models: natural streets, axial lines and axial segments. Four study areas (London, Paris, Manhattan and San Francisco) were picked up for empirical study. In the study, space syntax measures were calculated for different combinations of analytical methods and street models. These theoretical space syntax accessibility measures (connectivity, integration and choice) were correlated to the corresponding practical human movement to evaluate the correlations. Then the correlation results were compared in terms of analytical methods and street representation models respectively. In the end, the comparison of results show that (1) natural-street based model is the optimal street model for carrying out space syntax analysis followed by axial lines and axial segments; (2) angular analysis and topological analysis are more advanced than metric analysis; and (3) connectivity, integration and local integration (two-step) are more suitable for predicting human movements in space syntax. Furthermore, it can be hypothesized that topological analysis method with natural-street based model is the best combination for the prediction of human movements in space syntax, for the integration of topological and geometrical thinking.

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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Western Aeronautical Test Range (WATR) of NASA’s Dryden Flight Research Center (DFRC) is facing a challenge in meeting the technology demands of future flight mission projects. Rapid growth in technology for aircraft has resulted in complexity often surpassing the capabilities of the current WATR real-time processing and display systems. These current legacy systems are based on an architecture that is over a decade old. In response, the WATR has initiated the development of the WATR Integrated Next Generation System (WINGS). The purpose of WINGS is to provide the capability to acquire data from a variety of sources and process that data for subsequent analysis and display to Project Users in the WATR Mission Control Centers (MCCs) in real-time, near real-time and subsequent post-mission analysis. WINGS system architecture will bridge the continuing gap between new research flight test requirements and capability by distributing current system architectures to provide incremental and iterative system upgrades.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / At the 2007 iNet Technology Demonstrator multiple vendors are asked to participate to develop and evaluate protocols for time synchronization, configuration identification and heterogeneous data packet transfer. The iNet initiative from RCC is aimed at focusing and collating telemetry network developments within the wider sphere of commercial and military network developments. The KAM-500 is an inherently networked data-acquisition system offering seamless gateways to many heterogeneous data sources, such as different sensor devices, avionics-busses, networks and video sources. This paper offers insights into the impact of traffic and network configuration on the performance of heterogeneous data acquisition in a homogenous-switched network based a 1588 enabled controller module.

No description available.

Cerebral hypoperfusion can occur in normal ageing and is proposed to underlie white matter disturbances observed in the ageing brain. Moreover, cerebral hypoperfusion and white matter attenuation are early events in the progression of Alzheimer’s disease (AD). White matter mostly consists of myelinated axons which have distinct protein architecture, segregated into defined regions; the axon initial segment (AIS), the node of Ranvier, paranode, juxtaparanode, and internode. These sites are essential for action potential initiation and/or propagation and subsequently effective brain function. At the outset of the studies in the thesis there was evidence that the different regions within the myelinated axons are vulnerable to injury and disease. Thus it is hypothesised that in response to normal ageing and/or cerebral hypoperfusion these structures are altered and associated with cognitive impairment and that these effects are exacerbated in a transgenic mouse model (APPSw,Ind, J9 line) which develops age-dependent amyloid-β (Αβ) pathology. The first study aims to investigate the effect of normal ageing and Aβ deposition on myelinated axons and on learning and memory. To address this, the effects of normal ageing on the integrity of the AIS, nodes of Ranvier, myelin, axons, synapses and spatial working memory are examined in young and aged wild-type and TgAPPSw,Ind mice. A significant reduction in the length of nodes of Ranvier is demonstrated in aged wild-type and TgAPPSw,Ind mice. In addition, the length of AIS, is significantly reduced in the aged wild-type animals while the young TgAPPSw,Ind have significantly shorter AIS than the young wild-type mice. These effects are not influenced by the presence of Aβ. Myelin integrity is affected by age but this is more prominent in the wild-type animals whilst axonal integrity is intact. Moreover, there is an age-related decrease of presynaptic boutons only in the TgAPPSw,Ind mice. Contrary to the original hypothesis, working memory performance is not altered with age or influenced by increasing Aβ levels. The second study aims to examine the effects of cerebral hypoperfusion in combination with Αβ pathology and/or ageing on cognitive performance and the structure of myelinated axons. To address this, the effects of surgically induced cerebral hypoperfusion on the integrity of the nodes of Ranvier, paranodes, myelin, axons and spatial working memory performance are investigated in young and aged wild-type and TgAPPSw,Ind mice. A decrease in nodal length is observed in response to hypoperfusion in young and aged animals. This effect is shown to be exacerbated in the young TgAPPSw,Ind animals. Moreover, the disruption of the nodal domain is shown to occur without any gross alterations in myelin and axonal integrity. It is also demonstrated that in response to hypoperfusion, spatial working memory performance is defected in young and aged animals of both genotypes. This deficit is exacerbated in the young TgAPPSw,Ind. The observed changes in the nodal structure are associated with poor working memory performance indicating functional implication for the nodal changes. These data highlight that structures within myelinated axons are vulnerable to ageing and cerebral hypoperfusion. Therefore, the development of strategies that minimize injury or drive repair to these regions is necessary together with therapeutic approaches against the vascular insults that induce hypoperfusion and lead to white matter attenuation and cognitive decline. In the future, it would be interesting to investigate how alterations at the AIS/nodes of Ranvier affect neuronal excitability.

Sediment samples were collected during three Ocean Network Canada expeditions to three hydrothermal vent fields at the Endeavour segment of the Juan de Fuca Ridge. The sediments were collected at variable distances (≤ 1340 m) from the vents fields by push core and, in some cases, by suction sampling from base of a chimney structure. The geochemistry of the sediments was investigated in order to understand their formation and the mass fluxes associated with these hydrothermal systems. Qualitative and quantitative approaches have been applied to deconvolve sediments bulk compositions into mass fractions of the different components that they are made up of. Qualitative analysis identified five different end-member components (hydrothermal plume particles, hydrothermal chimney fragments, terrigenous sediment, basalt fragments and organic matter). Using Q-mode factor analysis only three main components are identified. This is due to the geochemical similarity of (i) the hydrothermal plume particles and hydrothermal chimney fragments which are grouped together in this analysis, and (ii) the terrigenous sediment and basalt which are also grouped. Mass fractions of each component were calculated by using a numerical inversion procedure. The samples collected at the base of the chimney are composed of 20-40% plume particles and 56-72% chimney fragments with little contribution from other sediment sources. With increasing distance from the vent fields the contributions of these “hydrothermal” sources to the sediments drop rapidly to <50% within 90 m of the vents and <25% within 120 m from the vents. The mass fraction and chemical composition of the plume particles component, along with the estimates of the chemical flux out of hydrothermal vents and sedimentation rates in the area, are used to make a preliminary estimation of the chemical flux into the ocean. / Graduate / 0372 / 0996 / 0547 / armaghan.attar@gmail.com

Thesis (MMed (Surgical Sciences. Orthopaedic Surgery))--University of Stellenbosch, 2010. / Objective: This research paper reports on the radiographic outcome of unstable thoracolumbar injuries with short segment posterior instrumentation as standalone treatment; in order to review rate of instrumentation failure and identify possible contributing factors. Background: Short segment posterior instrumentation is the treatment method of choice for unstable thoracolumbar injuries in the Acute Spinal Cord Injury Unit (Groote Schuur Hospital). It is considered adequate treatment in fracture cases with an intact posterior longitudinal ligament, and Gaines score below 7 (Parker JW 2000); as well as fracture dislocations, and seatbelt-type injuries (without loss of bone column - bearing integrity). The available body of literature often states instrumentation failure rates of up to 50% (Alanay A 2001, Tezeren G 2005). The same high level of catastrophic hardware failure is not evident in the unit researched. Methods: Sixty-five consecutive patients undergoing the aforementioned surgery were studied. Patients were divided into two main cohorts, namely the “Fracture group” (n=40) consisting of unstable burst fractures and unstable compression fractures; and the “Dislocation group” (n=25) consisting of fracture dislocations and seatbelt-type injuries. The groups reflect similar goals in surgical treatment for the grouped injuries, with reduction in loss of sagittal profile and maintenance thereof being the main aim in the fracture group, appropriately treated with Schantz pin constructs; and maintenance in position only, the goal in the dislocation group, managed with pedicle screw constructs. Data was reviewed in terms of complications, correction of deformity, and subsequent loss of correction with associated instrumentation failure. Secondly, factors influencing the aforementioned were sought, and stratified in terms of relevance. Results: Average follow up was 278 days for the fracture group and 177 days for the dislocation group (all patients included were deemed to have achieved radiological fusion – if fusion technique was employed). There was an average correction in kyphotic deformity of 10.25 degrees. Subsequent loss in sagittal profile averaged 2 degrees (injured level) and 5 degrees (thoracolumbar region) in the combined fracture and dislocation group. The only factor showing a superior trend in loss of reduction achieved was the absence of bone graft (when non-fusion technique was employed). Instrumentation complications occurred in two cases (bent connection rods in a Schantz pin construct with exaggerated loss in regional sagittal profile, and bent Schantz pins). These complications represent a 3.07% hardware failure in total. None of the failures were considered catastrophic. Conclusion: Short segment posterior instrumentation is a safe and effective option in the treatment of unstable thoracolumbar fractures as a standalone measure.

<b>Purpose:</b> Assess the relationship between tear film drying and sensation between blinks. <b>Methods:</b> MATLAB sampled a slitlamp video camera, a potentiometer and a microphone while subjects kept one eye open for as long as possible. 23 subjects rated the intensity of the ocular sensation while video and voice data were collected simultaneously. The tear drying on the cornea was measured. <b>Results:</b> The sensation was triphasic. Two linear functions described the latter 2 parts of the data (r &#8805; 0. 95). The correlation between TBUT and the elbow in the time-discomfort function was 0. 72. Extent of tear film drying was linearly correlated to time (median correlation = 0. 88). The correlation between the discomfort elbow and image elbow was 0. 93 with single data pair for each subject. Analysis of sensation characteristics showed significant differences between itching and burning for both intensity and time (p = 0. 03 and p = 0. 02 respectively). <b>Conclusions:</b> Simultaneous recording of ocular surface appearance, discomfort intensity and attributes of sensation provide novel information about the development of discomfort during ocular surface drying. The rapid increase in discomfort proceeding blinking has been quantified and the relationship between the time course of drying and discomfort is elucidated.

Both revenues and earnings of diversified firms are increasingly being reported, to the government and the public, on a subentity basis. Adequate criterial foundations do not exist to permit the effective general prescription of specific segment delineations, nor is it known whether such criterial assists can be usefully developed.Demands for segmentation in financial reports are currently intense. Actual reporting practices are largely nonstandardized as to either the definition of segments employed or, the disclosure modes used to present them. Neither conceptual nor theoretical supports are now adequate in guidance to the forms and levels of segmentation activity now required. Prerequisite to effective development of such supports is an-adequate understanding of the corporate diversification phenomenon itself. This dissertation project investigates and analyzes the nature of corporate diversification, as manifested in (1) its historical evolution; (2) general comprehensions of the phenomenon, as evidenced in published opinions and conceptual reasoning schemes of both authoritative experts and lay investors; and (3) formal research by others. Additionally, the results of these investigations and analyses are developed into conceptual schemes and theoretical frameworks, at moderate levels of abstraction.