33 research outputs found
Exploiting multi-word units in history-based probabilistic generation
We present a simple history-based model for sentence generation from LFG f-structures, which improves on the accuracy of previous models by breaking down PCFG independence assumptions so that more f-structure conditioning context is used in the prediction of grammar rule expansions. In addition, we present work on experiments with named entities and other multi-word units,
showing a statistically significant improvement of generation accuracy. Tested on section 23 of the PennWall Street Journal Treebank, the techniques described in this paper improve BLEU scores from 66.52 to 68.82, and coverage from 98.18% to 99.96%
The taxonomy and aspects of the ecology of the Ephemeroidea (Insecta: Ephemeroptera) of the Mooi River, KwaZulu-Natal Province, Republic of South Africa.
Thesis (M.Sc.)-University of KwaZulu- Natal, Pietermaritzburg, 2004.The Ephemeroidea or burrowing mayflies are a superfamily of the Ephemeroptera
(mayflies) with a worldwide distribution. Recent decades have seen a sharp decline
in their abundance globally. Literature reviews of the past 20 years have shown this
superfamily to be well represented on the Mooi River, KwaZulu-Natal- five species
(Eatonica schoutedeni, Ephemera mooiana, Afromera natalensis, Afroplocia sampsoni
and Ephoron savignyi) were recorded during the 20th century. However recent
fieldwork failed to confirm this professed diversity, recording only two species
(Afromera natalensis and Ephoron savignyi).
This work critically re-examined all of the literature relating to the
Ephemeroidea of Africa (in the context of the five species recorded from KwaZuluNatal)
published in Africa and Europe (as well as many publications from the rest of
the world) during the 19th and 20th century. It was found that a number of oversights
were made in much of this literature that have become assimilated into the
understanding of the taxonomy and ecology of this group. Amongst these, it was
found that the synonymisation of three species of Ephoron
( = Polymitarcys-Polymitarcys savignyi, P. capensis and P. temerata) in the 1920s was
weakly justified.
To clarify problems in the published record relating to the five species
recorded from KwaZulu-Natal, some of the most important museum holdings in
Europe and South Africa were re-examined. Two previously unknown collections of
Ephemera sp. were found in European museums. One of these collections was made
in West Africa, undermining theories that Ephemera sp. are only found in cold
waters. This research confirmed that the records for Eatonica schoutedeni in
KwaZulu-Natal are probably spurious, the result of misidentification. This work
presents a review of the publications relating to each of the species of the
Ephemeroidea recorded from KwaZulu-Natal. Lists of synonyms are provided.
Descriptions from literature and museum specimens are given. The known
distribution and biology of each is presented. The current status of the Ephemeroidea
of KwaZulu-Natal are discussed and a new key to the species of Kwazulu-Natal is
presented.
In order to assess the purported diversity of Ephemeroidea in the rivers of the
KwaZulu-Natal midlands, extensive fieldwork was carried out the Mooi River and on
other tributaries of the Tugela and Mgeni rivers from 1998 to 2000. This investigation
failed to reveal four of the five species indicated in the literature. The sole species that
was found, Ephoron savignyi was abundant in some areas of the Mooi and Karkloof
Rivers. This apparent drop in diversity may be because the sampling effort carried out
from 1998 to 2000 was too limited in time and space to gather specimens of all the
species resident in the river, or because environmental changes in the region in the
last 50 years have resulted in the extirpation of any or all of the remaining four
species.
It is concluded that the records of Eatonica schoutedeni from KwaZulu-Natal
are spurious; Ephemera mooiana is either not the only species in the genus Ephemera
on the continent of Africa, or has a substantially wider distribution than previously
thought; Afromera natalensis and Afroplocia sampsoni may be present on the rivers
of KwaZulu-Natal but have not been found during this research; Ephoron spp. are
abundant in KwaZulu-Natal, but further research is required to confirm that the
species in South Africa are the same as those originally recorded from the type
locality, Egypt
A numerical study on the sheltering effects of the central wind barriers on the Rose Fitzgerald Kennedy Bridge
The 2022 Civil Engineering Research in Ireland (CERI) and Irish Transportation Research Network (ITRN) Conference, Dublin, Ireland, 25-26th August 2022This study aims to examine the sheltering effects of central wind barriers installed near the pylons of the Rose Fitzgerald Kennedy Bridge. A full-scale Computational Fluid Dynamics (CFD) model is developed, which includes high-precision geometries of the bridge and the terrain. Simulations using this model are performed at realistic wind conditions as boundary conditions are mapped from mesoscale Weather Research and Forecasting (WRF) simulations. Wind velocities at multiple locations on the bridge predicted by the CFD simulations are compared with field measurement data where a good agreement is reached. The validated model is then applied with bridge geometries with and without the central wind barriers at high wind conditions. Comparisons between these two groups of simulations show that the wind barriers can effectively reduce wind velocities on traffic lanes near the pylon, which validates the current design of the barriers on the bridge.University College DublinChinese Scholarship Counci
Electropermanent magnetic anchoring for surgery and endoscopy
The use of magnets for anchoring of instrumentation in minimally invasive surgery and endoscopy has become of increased interest in recent years. Permanent magnets have significant advantages over electromagnets for these applications; larger anchoring and retraction force for comparable size and volume without the need for any external power supply. However, permanent magnets represent a potential hazard in the operating field where inadvertent attraction to surgical instrumentation is often undesirable. The current work proposes an interesting hybrid approach which marries the high forces of permanent magnets with the control of electromagnetic technology including the ability to turn the magnet OFF when necessary. This is achieved through the use of an electropermanent magnet, which is designed for surgical retraction across the abdominal and gastric walls. Our electropermanent magnet, which is hand-held and does not require continuous power, is designed with a center lumen which may be used for trocar or needle insertion. The device in this application has been demonstrated successfully in the porcine model where coupling between an intraluminal ring magnet and our electropermanent magnet facilitated guided insertion of an 18 Fr Tuohy needle for guidewire placement. Subsequent investigations have demonstrated the ability to control the coupling distance of the system alleviating shortcomings with current methods of magnetic coupling due to variation in transabdominal wall thicknesses. With further refinement, the magnet may find application in the anchoring of endoscopic and surgical instrumentation for minimally invasive interventions in the gastrointestinal tract
Design of a phase III multicenter trial to evaluate the efficacy of the RTS,S/AS01 malaria vaccine in children across diverse transmission settings in Africa
BACKGROUND\ud
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GlaxoSmithKline Biologicals and the PATH Malaria Vaccine Initiative are working in partnership to develop a malaria vaccine to protect infants and children living in malaria endemic regions of sub-Saharan Africa, which can be delivered through the Expanded Programme on Immunization. The RTS,S/AS candidate vaccine has been evaluated in multiple phase I/II studies and shown to have a favourable safety profile and to be well-tolerated in both adults and children. This paper details the design of the phase III multicentre efficacy trial of the RTS,S/AS01 malaria vaccine candidate, which is pivotal for licensure and policy decision-making.\ud
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METHODS\ud
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The phase III trial is a randomized, controlled, multicentre, participant- and observer-blind study on-going in 11 centres associated with different malaria transmission settings in seven countries in sub-Saharan Africa. A minimum of 6,000 children in each of two age categories (6-12 weeks, 5-17 months) have been enrolled. Children were randomized 1:1:1 to one of three study groups: (1) primary vaccination with RTS,S/AS01 and booster dose of RTS,S/AS01; (2) primary vaccination with RTS,S/AS01 and a control vaccine at time of booster; (3) primary vaccination with control vaccine and a control vaccine at time of booster. Primary vaccination comprises three doses at monthly intervals; the booster dose is administered at 18 months post-primary course. Subjects will be followed to study month 32. The co-primary objectives are the evaluation of efficacy over one year post-dose 3 against clinical malaria when primary immunization is delivered at: (1) 6-12 weeks of age, with co-administration of DTPwHepB/Hib antigens and OPV; (2) 5-17 months of age. Secondary objectives include evaluation of vaccine efficacy against severe malaria, anaemia, malaria hospitalization, fatal malaria, all-cause mortality and other serious illnesses including sepsis and pneumonia. Efficacy of the vaccine against clinical malaria under different transmission settings, the evolution of efficacy over time and the potential benefit of a booster will be evaluated. In addition, the effect of RTS,S/AS01 vaccination on growth, and the safety and immunogenicity in HIV-infected and malnourished children will be assessed. Safety of the primary course of immunization and the booster dose will be documented in both age categories.\ud
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CONCLUSIONS\ud
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This pivotal phase III study of the RTS,S/AS01 candidate malaria vaccine in African children was designed and implemented by the Clinical Trials Partnership Committee. The study will provide efficacy and safety data to fulfil regulatory requirements, together with data on a broad range of endpoints that will facilitate the evaluation of the public health impact of the vaccine and will aid policy and implementation decisions.\ud
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TRIAL REGISTRATION\ud
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Clinicaltrials.gov NCT00866619
Evaluation of RTS,S/AS02A and RTS,S/AS01B in Adults in a High Malaria Transmission Area
This study advances the clinical development of the RTS,S/AS01B candidate malaria vaccine to malaria endemic populations. As a primary objective it compares the safety and reactogenicity of RTS,S/AS01B to the more extensively evaluated RTS,S/AS02A vaccine.A Phase IIb, single centre, double-blind, controlled trial of 6 months duration with a subsequent 6 month single-blind follow-up conducted in Kisumu West District, Kenya between August 2005 and August 2006. 255 healthy adults aged 18 to 35 years were randomized (1ratio1ratio1) to receive 3 doses of RTS,S/AS02A, RTS,S/AS01B or rabies vaccine (Rabipur; Chiron Behring GmbH) at months 0, 1, 2. The primary objective was the occurrence of severe (grade 3) solicited or unsolicited general (i.e. systemic) adverse events (AEs) during 7 days follow up after each vaccination.Both candidate vaccines had a good safety profile and were well tolerated. One grade 3 systemic AE occurred within 7 days of vaccination (RTS,S/AS01B group). No unsolicited AEs or SAEs were related to vaccine. A marked increase in anti-CS antibody GMTs was observed post Dose 2 of both RTS,S/AS01B (31.6 EU/mL [95% CI: 23.9 to 41.6]) and RTS,S/AS02A (16.7 EU/mL [95% CI: 12.9 to 21.7]). A further increase was observed post Dose 3 in both the RTS,S/AS01B (41.4 EU/mL [95% CI: 31.7 to 54.2]) and RTS,S/AS02A (21.4 EU/mL [95% CI: 16.0 to 28.7]) groups. Anti-CS antibody GMTs were significantly greater with RTS,S/AS01B compared to RTS,S/AS02A at all time points post Dose 2 and Dose 3. Both candidate vaccines produced strong anti-HBs responses. Vaccine efficacy in the RTS,S/AS01B group was 29.5% (95% CI: -15.4 to 56.9, p = 0.164) and in the RTS,S/AS02A group 31.7% (95% CI: -11.6 to 58.2, p = 0.128).Both candidate malaria vaccines were well tolerated over a 12 month surveillance period. A more favorable immunogenicity profile was observed with RTS,S/AS01B than with RTS,S/AS02A.Clinicaltrials.gov NCT00197054
Evaluation of two formulations of adjuvanted RTS, S malaria vaccine in children aged 3 to 5 years living in a malaria-endemic region of Mozambique: a Phase I/IIb randomized double-blind bridging trial
BACKGROUND: Previous trials of the RTS, S malaria candidate vaccine have shown that this vaccine is safe, tolerated and immunogenic. The development plan for this vaccine aims at administering it in the first year of life through the Expanded Program on Immunization (EPI). The objective was to evaluate the safety and reactogenicity of RTS, S/AS02D (0.5 ml dose), a pediatric formulation of GlaxoSmithKline Biologicals' current malaria candidate vaccine RTS, S/AS02A (0.25 ml dose). A 0.5 ml dose of AS02D is composed of the same active ingredients in the same quantities as in a 0.25 ml dose of AS02A and has been developed to be easily introduced into routine EPI practices. METHODS: We performed a phase I/IIb randomized double-blind bridging study in a malaria-endemic region of Mozambique, to compare the safety and immunogenicity of both candidate vaccines with the aim of replacing RTS, S/AS02A with RTS, S/AS02D as the candidate pediatric vaccine. 200 Mozambican children aged 3 to 5 years were randomized 1:1 to receive one of the 2 vaccines according to a 0, 1, 2 month schedule. RESULTS: Both vaccines were safe and had similar reactogenicity profiles. All subjects with paired pre and post-vaccination samples showed a vaccine response with respect to anti-circumsporozoite (CS) antibodies irrespective of initial anti-CS serostatus. Geometric mean titers (GMTs) were 191 EU/ml (95% CI 150–242) in recipients of RTS, S/AS02D compared to 180 EU/ml (95% CI 146–221) in recipients of RTS, S/AS02A. For the anti-hepatitis B surface antigen (HBsAg), all subjects were seroprotected at day 90, and the GMTs were 23978 mIU/ml (95% CI 17896–32127) in RTS, S/AS02D recipients and 17410 mIU/ml (95% CI 13322–22752) in RTS, S/AS02A recipients. There was a decrease in anti-CS GMTs between months 3 and 14 in both groups (191 vs 22 EU/mL in RTS, S/AS02D group and 180 vs 29 EU/mL in RTS, S/AS02A group). CONCLUSION: Our data show that the RTS, S/AS02D is safe, well tolerated, and demonstrates non-inferiority (defined as upper limit of the 95% confidence interval of the anti-CS GMT ratio of RTS, S/AS02A to RTS, S/AS02D below 3.0) of the antibody responses to circumsporozoite and HBsAg induced by the RTS, S/AS02D as compared to the RTS, S/AS02A
Federating Heterogeneous Event Services
As event-based middleware is currently being applied for application component integration in a range of application areas, a variety of event services have been proposed to address different application requirements. The emergence of ubiquitous computing systems has given rise to application integration across multiple areas and as a result, has led to systems comprising several, independently operating event services. Even though event services are based on the same communication pattern, application component integration across heterogeneous services is typically prevented by the constraints imposed by their respective event models. This paper presents the design..
Locally Adaptive Deblocking Filter
Blocking artifacts are a major degradation affecting blockbased video compression. In this paper an adaptively based filter is proposed, whereby the type of filtering to be applied is chosen based on local image characteristics. Having three modes of filtering, it allows for strong filtering in flat areas where the blocking effect is most noticeable, detail preserving filtering in highly complex regions, while allowing for the smoothing of intermediate areas without excessively blurring the image. Objective, and more notably subjective testing, show the effectiveness of the proposed postprocessing technique. PSNR improvements of the order of 0.3 dB are found compared to the non-postprocessed image. Computational demands (less than a million operations per QCIF frame) make the proposed method practical for real time implementation
Exploiting Multi-Word Units in History-Based Probabilistic Generation
We present a simple history-based model for sentence generation from LFG f-structures, which improves on the accuracy of previous models by breaking down PCFG independence assumptions so that more f-structure conditioning context is used in the prediction of grammar rule expansions. In addition, we present work on experiments with named entities and other multi-word units, showing a statistically significant improvement of generation accuracy. Tested on section 23 of the Penn Wall Street Journal Treebank, the techniques described in this paper improve BLEU scores from 66.52 to 68.82, and coverage from 98.18 % to 99.96%.