283 research outputs found
A benchmark activity on the fatigue life assessment of AlSi10Mg components manufactured by L-PBF
One of the challenges associated with additive manufacturing (AM) is the definition of an assessment route which considers the main process signatures of the AM process. To this end, this work presents a complete benchmark activity for the assessment of an AlSi10Mg component produced by a laser pow- der bed fusion process, aimed at advancing the understanding of the fatigue resistance of AM materials with particular focus on the comparison between the fatigue performances of small coupons and demon- strators. Four builds of AlSi10Mg specimen geometries were manufactured to: (i) determine the fatigue curves for both as-built and machined conditions; (ii) measure the fatigue crack growth rate; (iii) produce and test under fatigue a benchmark component used as a reference for the validation of the fatigue assessment procedure. Tools and concepts of flaw tolerance were then used to perform the fatigue assess- ment of the benchmark component and were shown to be successful in the life prediction. Results obtained from this wide database (related to internal defects and surface features) show that only a fracture-based fatigue assessment is able to provide precise life estimates consistent with material crack growth properties. Eventually, all the experimental results including specimens design, analysis of frac- ture surfaces and raw testsā data will be made available in a database which can be accessed and used by the industrial and scientific communities to calibrate and validate alternative fatigue assessment proce- dures of AM parts
Personal wellbeing in posttraumatic stress disorder (PTSD): Association with PTSD symptoms during and following treatment
Ā© 2018 The Author(s). Background: It remains unclear to what extent treatment-related gains in posttraumatic stress disorder (PTSD) symptoms translate to improvements in broader domains of personal wellbeing, such as community connectedness, life achievement and security. We sought to determine whether: 1. personal wellbeing improves during the course of a treatment program and 2. changes in core symptom domains (PTSD, anxiety and depression) were associated with improvements in overall personal wellbeing. Methods: Participants (N=124) completed the PTSD Checklist, the Depression and Anxiety Stress Scales and the Personal Wellbeing Index at the start and end of a 4-week Trauma Focused CBT residential program, as well as 3- and 9-months post-treatment. Results: Personal wellbeing improved significantly across the 9-months of the study. Generalised estimating equations analyses indicated that (older) age and improvements in PTSD and depressive symptoms were independent predictors of personal wellbeing across time. Conclusions: Although personal wellbeing improved in tandem with PTSD symptoms, the magnitude of improvement was small. These findings highlight a need to better understand how improvements in personal wellbeing can be optimised following PTSD treatment
Characterisation of a refined rat model of respiratory infection with Pseudomonas aeruginosa and the effect of ciprofloxacin
AbstractBackgroundWe sought to characterise a refined rat model of respiratory infection with P. aeruginosa over an acute time course and test the antibiotic ciprofloxacin.MethodsAgar beads were preparedĀ±SPANĀ®80. Rats were inoculated with sterile agar beads or those containing 105 colony forming units (cfu) P. aeruginosa via intra-tracheal dosing. Bacterial load and inflammatory parameters were measured.ResultsDiffering concentrations of SPANĀ® 80 modified median agar bead diameter and reduced particle size distribution. Beads prepared with 0.01% v/v SPANĀ®80 were evaluated in vivo. A stable lung infection up to 7days post infection was achieved and induced BALF neutrophilia 2 and 5days post infection. Ciprofloxacin (50mg/kg) significantly attenuated infection without affecting the inflammatory parameters measured.ConclusionSPANĀ® 80 can control the particle size and lung distribution of agar beads and P. aeruginosa-embedded beads prepared with 0.01%v/v SPANĀ®80 can induce infection and inflammation over 7days
Seminar Users in the Arabic Twitter Sphere
We introduce the notion of "seminar users", who are social media users
engaged in propaganda in support of a political entity. We develop a framework
that can identify such users with 84.4% precision and 76.1% recall. While our
dataset is from the Arab region, omitting language-specific features has only a
minor impact on classification performance, and thus, our approach could work
for detecting seminar users in other parts of the world and in other languages.
We further explored a controversial political topic to observe the prevalence
and potential potency of such users. In our case study, we found that 25% of
the users engaged in the topic are in fact seminar users and their tweets make
nearly a third of the on-topic tweets. Moreover, they are often successful in
affecting mainstream discourse with coordinated hashtag campaigns.Comment: to appear in SocInfo 201
Bioprospecting for biological control agents for invasive tilapia in Australia
Originating in Africa, tilapia (Pisces, Cichlidae) now have a worldwide distribution and are both a prime model system for evolutionary biology and an important aquaculture species in over 135 countries. In contrast, Mozambique tilapia (Oreochromis mossambicus) is also listed in the top 100 of the world's worst invasive alien species and has been documented to have severe impacts on freshwater ecosystems primarily through displacement of native species and habitat alteration. In Australia, both O. mossambicus and the lesser-known spotted tilapia (Tilapia mariae) have established significant populations within Queensland waters, and recent incursions into northern New South Wales are of great concern. Eradication attempts using a combination of electrofishing and piscicide (poison) are rarely successful in open waterways, and given their invasive nature, there is a lack of demonstrated broad-scale effective control mechanisms for tilapia. Biological control (biocontrol), where it is feasible can be a cost-effective, a safe (species specific) and practical solution to managing invasive species because it does not require reapplication of chemicals or poisons, and once established should be self-sustaining. Based on the development of previous viral biocontrol strategies for rabbits and carp, we used a robust assessment framework for bioprospecting of biocontrol agents and found that tilapia lake virus (TiLV), and possibly tilapia parvovirus (TiPV), may offer the potential for biocontrol for invasive tilapia in Australia. TiLV causes high mortality in wild and cultured tilapia, but not in other species, and spreads through a waterborne route - an important transmission pathway for a successful viral biocontrol of fish. However, safety and efficacy, two major concerns for a successful biocontrol virus, need to be taken into consideration before the use of any exotic biocontrol virus is considered. Herein, we describe a systematic approach to assess known pathogens for their suitability as potential agents for biological control of tilapia and outline the possible next steps to further investigate the top candidates
Special Libraries, October 1922
Volume 13, Issue 8https://scholarworks.sjsu.edu/sla_sl_1922/1007/thumbnail.jp
Privacy in crowdsourcing:a systematic review
The advent of crowdsourcing has brought with it multiple privacy challenges. For example, essential monitoring activities, while necessary and unavoidable, also potentially compromise contributor privacy. We conducted an extensive literature review of the research related to the privacy aspects of crowdsourcing. Our investigation revealed interesting gender differences and also differences in terms of individual perceptions. We conclude by suggesting a number of future research directions.</p
Sports-related injuries in New Zealand: National Insurance (Accident Compensation Corporation) claims for five sporting codes from 2012 to 2016
**Objectives** To provide epidemiological data and related costs for sport-related injuries of five sporting codes (cricket, netball, rugby league, rugby union and football) in New Zealand for moderate-to-serious and serious injury claims.
**Methods** A retrospective analytical review using detailed descriptive epidemiological data obtained from the Accident Compensation Corporation (ACC) for 2012ā2016.
**Results** Over the 5āyears of study data, rugby union recorded the most moderate-to-serious injury entitlement claims (25 226) and costs (New Zealand dollars (NZD10 484 (Ā£5454)) per moderate-to-serious injury entitlement claim. Rugby union recorded more serious injury entitlement claims (n=454) than cricket (t(4)=ā66.6; P<0.0001); netball (t(4)=ā45.1; P<0.0001); rugby league (t(4)=ā61.4; P<0.0001) and football (t(4)=66.6; P<0.0001) for 2012ā2016. There was a twofold increase in the number of female moderate-to-serious injury entitlement claims for football (RR 2.6 (95%CI 2.2 to 2.9); P<0.0001) compared with cricket, and a threefold increase when compared with rugby union (risk ratio (RR) 3.1 (95%CI 2.9 to 3.3); P<0.0001). Moderate-to-serious concussion claims increased between 2012 and 2016 for netball (RR 3.7 (95%CI 1.9 to 7.1); P<0.0001), rugby union (RR 2.0 (95% CI 1.6 to 2.4); P<0.0001) and football (RR 2.3 (95%CI 1.6 to 3.2); P<0.0001). Nearly a quarter of moderate-to-serious entitlement claims (23%) and costs (24%) were to participants aged 35 years or older.
**Conclusions** Rugby union and rugby league have the highest total number and costs associated with injury. Accurate sport exposure data are needed to enable injury risk calculations
Comprehensive policy review of anti-trafficking projects funded by the EU
The study reviews the 300+ projects that were funded by the EU in relation to their anti-trafficking policy, between 2012-2016, at a cost of 158.5m euros. The study explores the nature and geographic distribution of these projects. It also examines the activity and outcomes related to them for areas of good practice. Using this information the study examines the current EC strategy and makes recommendations for the future strategy
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