137 research outputs found
Flow beneath inland navigation vessels
No full textGrowing transportation rates and the subsequent growth in inland waterway transport have led to an increase in inland vessel sizes and draught. Due to the fluctuating water levels on rivers and these increasing draughts, the distance between the river bed and the ships are decreasing. Rijkswaterstaat wants to know the effects of sailing at these small underkeel clearances on river beds and ship manoeuvrability. In order to quantify these effects, more knowledge about the flow field beneath sailing vessels is required, as well as the effect of the flow field on erosion of bed material. Currently no methods exist to determine the flow field beneath vessels, only a few formulations for a single maximum velocity value are available, but these are not applicable at small underkeel clearances (h / T < 1.25). Also the effect on the river bed is fairly unknown. To quantify the different effects of small underkeel clearances on the flow field physical model tests (with a length scale of 30) have been performed at Deltares. During these experiments a ship was towed through the flume, and flow velocities and pressures on the bed were measured, as well as forces on the ship. Additional experiments have been performed to investigate the effect on a moveable bed with different bed forms. From the experiments, it was found that the most important parameters that influence the flow field beneath the keel are the bow shape and the underkeel clearance. Barge bows force more flow underneath the keel than conventional bows, and this results in higher bed velocities. Decreasing keel clearances also result in significantly higher velocities at the bed. However, for very small underkeel clearances the boundary layer on the ship will interact with the boundary layer on the bed. This results in flow blockage underneath the keel. As a result, the flow needs to divert to the sides, and the velocities underneath the keel decrease. The diversion of the flow to the sides is also known as the fanning-out effect. This effect has definitely been proved by the measurements from the experiments. The effect (transverse velocities) increases with decreasing keel clearance (due to boundary layer interaction) and also increases with increasing ship widths. During the experiments, erosion of bed material was clearly observed, and its effect increased with decreasing keel clearance. However, the underkeel clearance needs to be very small (h /UKC < 1.1) to give significant bed erosion. Due to the fanning-out effect and turbulence fluctuations, most sediment transport occurred immediately alongside the vessel, rather than underneath the keel. With bed forms such as dunes the erosion increased, due to erosion at the dune tops and deposition in the troughs (10 passages of a conventional vessel over a dune resulted in a decrease in dune height of 20%). For the removal of small shoals this might be interesting, although a small underkeel clearance is necessary. Barges are preferred over conventional vessels due to the higher velocities and increased turbulence intensity. From the measured velocities during the physical model tests a model has been developed to predict the flow field underneath sailing inland navigation vessels. There are separate models for conventional vessels and for barges. The model is able to accurately predict maximum velocities (in sailing direction as well as in transverse direction), as well as a transverse velocity distribution. Compared to the previous prediction methods, the newly developed model is preferable. The results are more accurate, and the model is more extensive, due to the inclusion of transverse velocities and velocity distributions. More validation is required however, due to the lack of other data sets.Hydraulic EngineeringCivil Engineering and Geoscience
Screening forCronobacterSpecies in Powdered and Reconstituted Infant Formulas and from Equipment Used in Formula Preparation in Maternity Hospitals
No full textBackground/Aims: Cronobacter spp. have been identified as being of considerable risk to neonates. The occurrence of organism in infant formulas is therefore of considerable interest. Methods: The occurrence of Cronobacter spp. in infant feeds (formulas and fortified cow’s milk) was determined using most probable number (MPN) analysis, and from formula preparation utensils. Ninety nine samples were analyzed, of which 42 were unopened cans of powdered infant formula (PIF), 25 reconstituted infant formulas in feeding bottles, 27 utensils used from the preparation of infant formula, and 5 samples of fortified cow’s milk. Presumptive Cronobacter spp. isolates were identified using the 7 allele multilocus sequence typing (MLST) scheme. Results: C. sakazakii, C. malonaticus and C. muytjensii were recovered from PIF. Although the incidence of Cronobacter in PIF was 29% (12/42), the level was low with an average of 0.54 MPN/100g. According to MLST profiling, C. sakazakii was the most frequently isolated Cronobacter species, and C. sakazakii ST4 (associated with neonatal meningitis) was recovered from 2/42 PIF samples at 0.51 and 0.92 MPN/100g. Conclusions: Cronobacter spp. can be isolated from PIF and therefore strict hygienic practices during PIF preparation are important to minimize neonate exposure and reduce the risk of severe infections
The role of mobile technology for fall risk assessment for individuals with multiple sclerosis
No full textMultiple Sclerosis (MS) is a chronic, progressive neurogenerative disease that affects one million people in the United States (Wallin et al., 2019). Common MS symptoms include impaired coordination, poor walking and balance, and fatigue, and these symptoms put people with MS (pwMS) at a higher risk for falls (Cameron & Nilsagard, 2018). Falls are highly prevalent among pwMS and can result in detrimental consequences including bone fractures and even death (Matsuda et al., 2011). To prevent falls and fall related injuries, it is important to first assess for multiple risk factors and then intervene through targeted treatments (Palumbo et al., 2015).
Fall risk can be assessed through self-report measures, clinical performance tests, or with technology such as force plates and motion capture systems (Kanekar & Aruin, 2013). However, clinicians have time constraints, technology is expensive, and trained personnel is needed. Moreover, due to the COVID-19 pandemic, access to in-person clinical visits is limited. As a result, pwMS may not receive fall risk screening and remain vulnerable to fall related injuries. Mobile technology offers a solution to increase access to fall risk screening using an affordable, ubiquitous, and portable tool (Guise et al., 2014; Marrie et al., 2019). Therefore, the overarching goal of this study was to develop a usable fall risk health application (app) for pwMS to self-assess their fall risk in the home setting. Four studies were performed: 1) smartphone accelerometry was tested to measure postural control in pwMS; 2) a fall risk algorithm was developed for a mobile health app; 3) a fall risk app, Steady-MS, was developed and its usability was tested; and 4) the feasibility of home-based procedures for using Steady-MS was determined. Results suggest that smartphone accelerometry can assess postural control in pwMS. This information was used to develop an algorithm to measure overall fall risk in pwMS and was then incorporated into Steady-MS. Steady-MS was found to be usable among MS users and feasible to use in the home setting. The results from this project demonstrate that pwMS can independently assess their fall risk with Steady-MS in their homes. For the first time, pwMS are equipped to self-assess their fall risk and can monitor and manage their risk. Home-based assessments also opens the potential to offer individualized and targeted treatments to prevent falls. Ultimately, Steady-MS increases access to home-based assessments to reduce falls and improve functional independence for those with MS.Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2020-10-02 without embargo termsThe student, Katherine Hsieh, accepted the attached license on 2020-06-26 at 16:01.The student, Katherine Hsieh, submitted this Dissertation for approval on 2020-06-26 at 16:18.This Dissertation was approved for publication on 2020-07-01 at 17:28.DSpace SAF Submission Ingestion Package generated from Vireo submission #15472 on 2020-10-02 at 15:10:39Made available in DSpace on 2020-10-07T20:59:26Z (GMT). No. of bitstreams: 2
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Previous issue date: 2020-07-0
Beyond the Catholic-Protestant divide : religious and ethnic diversity in the North and South of Ireland
No full textPaper presented to the IBIS conference Old structures, new beliefs: religion, community and politics in contemporary Ireland, University College Dublin, 15 May 2003.This paper explores the challenges posed by the ethnic diversification of contemporary Irish society for conventional understandings of and responses to issues of religion, community and politics. It argues that the particularities of social and institutional histories and structures in the North and South have eclipsed wider considerations of both race and ethnicity and religious identity beyond the Catholic-Protestant divide. This has, in turn, served to obscure the many dynamic changes that such diversity has catalysed both within Irish civil society generally, and within the island’s traditional religious institutions themselves. The paper discusses the promises and potentials of conceptualising religion or religious identity and the relationships between religion and ethnicity within broader cultural and political fields, and their implications for the “new” (multicultural) Ireland.Not applicableti -TS 07.07.10
Author is part of the school of Sociolog
Genetic basis of benzimidazole resistance in Teladorsagia circumcincta in Ireland
No full textpeer-reviewedResistance to benzimidazole (BZ) anthelmintics is common in ovine nematodes of economic importance. Single nucleotide polymorphisms (SNP) at three positions in the isotype 1 β– tubulin gene have been associated with BZ resistance and molecular tests for the detection of BZ resistance have been developed. In order to determine if such tests are practicable in Ireland the polymorphisms associated with BZ resistance must be identified. To this end, BZ-resistant nematodes were recovered from four farms in Ireland. Resistant Teladorsagia circumcincta, Cooperia curticei and Trichostrongylus colubriformis were recovered, with resistant T. circumcincta the most common and the only species studied further. Sequencing of the isotype 1 β–tubulin gene from resistant T. circumcincta identified a T - A transition, resulting in an F200Y substitution known to be responsible for BZ-resistance, on three of the farms. However, on the fourth farm the frequency of the resistant A allele was only 0.33 indicating another BZ resistance mechanism may be present on this farm. An additional polymorphism resulting in a substitution of glutamate for leucine (E198L) was also found on this farm at low frequency (0.17). No polymorphisms at position 167 were identified on any farm. Therefore, molecular tests to detect BZ resistance in T. circumcincta in Ireland could prove useful; however, they may result in some instances of resistance remaining undetected
Tobacco Use, Taxation and Self Control in Adolescence
No full textRecent literature has suggested that higher taxes on addictive goods could increase welfare by assisting individuals with self control problems and trouble resisting 'temptation’. In contrast, if individuals continue to use despite increased prices, taxation may serve to reduce the welfare of these individuals while providing no benefits in managing self control nor mitigating externalities. We use data on adolescents from the National Longitudinal Study of Adolescent Health (Add Health) to examine the impact of tobacco taxes on smoking. To account for unobserved heterogeneity in response to taxes we estimate finite mixture models, positing two types of individuals with differential responses to taxes. We find evidence of differential price elasticity for tobacco use across the adolescents groups, and show that individuals with low self control or high discount rates are largely unresponsive to cigarette price. Those who have the least willpower may need the most help in quitting but are unresponsive to taxes, suggesting that policies other than taxation may be needed to reduce adolescent tobacco use.
Angle of attack of the tail-membrane during fanning motion.
No full text<p>Graphic illustrating how the tail-membrane produces foreward thrust during a platform takeoff. The tip of the tail moves along a sinusoidal path through each stroke cycle represented by the curved black-line. Blue lines indicate the position of the tail-membrane relative to the sinusoidal path. The upstroke of the folded tail-membrane would likely be aerodynamically passive, whereas the downstroke provides a thrust force realtive to pitch angle and angle of attack. Numbers indicate tail-membrane position from top to bottom for a single downstroke. T = Thrust, L = Lift, D = Drag. Inset diagram illustrates how angle of attack and pitch angle were calculated for each tail-membrane position during the downstroke. A path tangent was drawn for each point position of the tail tip. α is the angle of attack of the tail-membrane relative to path (here illustrated for position 4 of the downstroke).</p
IMOVE: Protocol for a randomized, controlled 2x2 factorial trial of improvisational movement and social engagement interventions in older adults with early Alzheimer's disease
No full textBackground: In addition to cognitive impairment, people with Alzheimer's disease (PWAD) experience neuropsychiatric symptoms (e.g., apathy, depression), altered gait, and poor balance that further diminish their quality of life (QoL). Here, we describe a unique, randomized, controlled trial to test the hypothesis that both movement and social engagement aspects of a group dance intervention alter the connectivity of key brain networks involved in motor and social-emotional functioning and lead to improved QoL in PWAD. Methods: IMOVE (NCT03333837) was a single-center, randomized, controlled 2x2 factorial trial that assigned PWAD/caregiver dyads to one of 4 study conditions (Movement Group, Movement Alone, Social Group, or Usual Care control). The Movement Group participated in twice-weekly group improvisational dance (IMPROVment® Method) classes for 12 weeks. The Movement Alone intervention captured the same dance movement and auditory stimuli as the group class without social interaction, and the Social Group used improvisational party games to recapitulate the fun and playfulness of the Movement Group without the movement. The primary outcome was change in QoL among PWAD. Key secondary outcomes were functional brain network measures assessed using graph-theory analysis of resting-state functional magnetic resonance imaging scans, as well as neuropsychiatric symptoms, gait, and balance. Results: A total of 111 dyads were randomized; 89 completed the study, despite interruption and modification of the protocol due to COVID-19 restrictions (see companion paper by Fanning et al.). The data are being analyzed and will be submitted for publication in 2023
Comparison of methods for the microbiological identification and profiling of cronobacter species from ingredients used in the preparation of infant formula
No full textCronobacter spp. (formerly Enterobacter sakazakii) can be isolated from a wide range of foods and environments, and its association with neonatal infections has drawn considerable attention from regulatory authorities. The principle route of neonatal infection has been identified as the ingestion of contaminated infant formula. A number of methods have been developed to identify Cronobacter spp., however these were before the most recent (2012 ) taxonomic revision of the genus into seven species. In this study, phenotyping, protein profiling and molecular methods were used to identify Cronobacter strains which had been recently isolated from ingredients used in the preparation of infant formula. Pulsed field gel electrophoresis revealed that different Cronobacter strains had been recovered from the same food products. All isolates were identified as C sakazakii according to four genus specific PCR-probes and protein profiling using MALDI-TOF analysis. However, 16S rDNA sequence analyses and fusA allele sequencing gave more accurate identification: four strains were C sakazakii, one strain was C malonaticus and the remaining strain was C universalis. Multilocus sequence typing showed the strains were different sequence types. These results demonstrate the presence of different Cronobacter species in food ingredients used in the preparation of infant formula, and also the need for molecular identification and profiling methods to be revised according to taxonomic revisions
Opioid mediated activity and expression of mu and delta opioid receptors in isolated human term non-laboring myometrium
No full textThe existence of opioid receptors in mammalian myometrial tissue is now widely accepted. Previously enkephalin degrading enzymes have been shown to be elevated in pregnant rat uterus and a met-enkephalin analogue has been shown to alter spontaneous contractility of rat myometrium. Here we have undertaken studies to determine the effects of met-enkephalin on in vitro human myometrial contractility and investigate the expression of opioid receptors in pregnant myometrium. Myometrial biopsies were taken from women undergoing elective caesarean delivery at term. Organ bath experiments were used to investigate the effect of the met-enkephalin analogue [d-Ala 2, d-met 5] enkephalin (DAMEA) on spontaneous contractility. A confocal immunofluorescent technique and real time PCR were used to determine the expression of protein and mRNA, respectively for two opioid receptor subtypes, mu and delta. DAMEA had a concentration dependent inhibitory effect on contractile activity (1×10−7 M–1×10−4 M; 54% reduction in contractile activity, P<0.001 at 1×10−4 M concentration). Mu and delta opioid receptor protein sub-types and their respective mRNA were identified in all tissues sampled. This is the first report of opioid receptor expression and of an opioid mediated uterorelaxant action in term human non-labouring myometrium in vitroSB. 21/03/201
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