268 research outputs found
Stochastic Programming and Distributionally Robust Optimization Approaches for Location and Inventory Prepositioning of Disaster Relief Supplies
In this paper, we study the problem of disaster relief inventory
prepositioning under uncertainty. Specifically, we aim to determine where to
open warehouses and how much relief item inventory to preposition in each,
pre-disaster. During the post-disaster phase, prepositioned items are
distributed to demand nodes, and additional items are procured and distributed
as needed. There is uncertainty in the (1) disaster level, (2) locations of
affected areas, (3) demand of relief items, (4) usable fraction of
prepositioned items post-disaster, (5) procurement quantity, and (6) arc
capacity. We propose and analyze two-stage stochastic programming (SP) and
distributionally robust optimization (DRO) models, assuming known and unknown
uncertainty distributions, respectively. The first and second stages correspond
to pre- and post-disaster phases, respectively. We propose a Monte Carlo
Optimization procedure to solve the SP and a decomposition algorithm to solve
the DRO model. To illustrate potential applications of our approaches, we
conduct extensive experiments using a hurricane season and an earthquake as
case studies. Our results demonstrate the (1) the robustness and superior
post-disaster operational performance of the DRO decisions under various
distributions compared to SP decisions, especially under misspecified
distributions and high variability, (2) the trade-off between considering
distributional ambiguity and following distributional belief, and (3)
computational efficiency of our approaches
The effect of temperature on the elastic precursor decay in shock loaded FCC aluminium and BCC iron
EPSRC under Established Career Fellowship grant EP/N025954/1.
Trinity College Cambridge
Institute of Shock Physics
Research Board and the Faculty of Engineering Dean’s office at the American University of Beiru
A preliminary assessment of the effects of ATI-2042 in subjects with paroxysmal atrial fibrillation using implanted pacemaker methodology
Aims ATI-2042 (budiodarone) is a chemical analogue of amiodarone with a half life of 7 h. It is electrophysiologically similar to amiodarone, but may not have metabolic and interaction side effects. The sophisticated electrocardiograph logs of advanced DDDRP pacemakers were used to monitor the efficacy of ATI-2042. The aim of this study was to determine the preliminary efficacy and safety of ATI-2042 in patients with paroxsymal atrial fibrillation (PAF) and pacemakers.
Methods and results Six women with AF burden (AFB) between 1 and 50% underwent six sequential 2-week study periods. Patients received 200 mg bid of ATI-2042 during Period 2 (p2), 400 mg bid during p3, 600 mg bid during p4, 800 mg bid during p5, and no drug during baseline and washout (p1 and p6). Pacemaker data for the primary outcome measure AFB were downloaded during each period. Mean AFB decreased between baseline and all doses: AFB at baseline (SD) was 20.3 ± 14.6% and mean AFB at 200 mg bid was 5.2 ± 4.2%, at 400 mg bid 5.2 ± 5.2%, at 600 mg bid 2.8 ± 3.4%, and at 800 mg bid 1.5 ± 0.5%. The mean reductions in AFB at all doses of ATI-2042 were statistically significant (P < 0.005). Atrial fibrillation burden increased in washout. Atrial fibrillation episodes tended to increase with ATI-2042, but this was offset by substantial decreases in episode duration. ATI-2042 was generally well tolerated.
Conclusion ATI-2042 effectively reduced AFB over all doses studied by reducing mean episode duration. A large-scale study will be required to confirm this effect
Rethinking justice beyond human rights. Anti-colonialism and intersectionality in the politics of the Palestinian Youth Movement
This article discusses the politics of the Palestinian Youth Movement (PYM) – a contemporary social movement operating across a number of Arab and western countries. Unlike analysis on the Arab Uprisings which focused on the national dimension of youth activism, we explore how the PYM politics fosters and upholds an explicitly transnational anti-colonial and intersectional solidarity framework, which foregrounds a radical critique of conventional notions of self-determination based on state-framed human rights discourses and international law paradigms. The struggle becomes instead framed as an issue of justice, freedom and liberation from interlocking forms and hierarchies of oppression.
KEYWORDS: Palestine, transnational social movements, intersectionality, human rights, anti-colonialis
Improving mental health and psychosocial wellbeing in humanitarian settings: reflections on research funded through R2HC
Establishing glycaemic control with continuous subcutaneous insulin infusion in children and adolescents with type 1 diabetes: experience of the PedPump Study in 17 countries
AIMS/HYPOTHESIS: To assess the use of paediatric continuous subcutaneous infusion (CSII) under real-life conditions by analysing data recorded for up to 90 days and relating them to outcome. METHODS: Pump programming data from patients aged 0-18 years treated with CSII in 30 centres from 16 European countries and Israel were recorded during routine clinical visits. HbA(1c) was measured centrally. RESULTS: A total of 1,041 patients (age: 11.8 +/- 4.2 years; diabetes duration: 6.0 +/- 3.6 years; average CSII duration: 2.0 +/- 1.3 years; HbA(1c): 8.0 +/- 1.3% [means +/- SD]) participated. Glycaemic control was better in preschool (n = 142; 7.5 +/- 0.9%) and pre-adolescent (6-11 years, n = 321; 7.7 +/- 1.0%) children than in adolescent patients (12-18 years, n = 578; 8.3 +/- 1.4%). There was a significant negative correlation between HbA(1c) and daily bolus number, but not between HbA(1c) and total daily insulin dose. The use of 7.5%. The incidence of severe hypoglycaemia and ketoacidosis was 6.63 and 6.26 events per 100 patient-years, respectively. CONCLUSIONS/INTERPRETATION: This large paediatric survey of CSII shows that glycaemic targets can be frequently achieved, particularly in young children, and the incidence of acute complications is low. Adequate substitution of basal and prandial insulin is associated with a better HbA(1c)
RAGE and Modulation of Ischemic Injury in the Diabetic Myocardium
OBJECTIVE—Subjects with diabetes experience an increased risk of myocardial infarction and cardiac failure compared with nondiabetic age-matched individuals. The receptor for advanced glycation end products (RAGE) is upregulated in diabetic tissues. In this study, we tested the hypothesis that RAGE affected ischemia/reperfusion (I/R) injury in the diabetic myocardium. In diabetic rat hearts, expression of RAGE and its ligands was enhanced and localized particularly to both endothelial cells and mononuclear phagocytes
Towards a modular language curriculum for using tasks
Task-based language teaching (TBLT) and task-supported language teaching (TSLT) are often seen as incompatible as they draw on different theories of language learning and language teaching. The position adopted in this article, however, is that both approaches are needed especially in instructional contexts where ‘pure’ task-based teaching may be problematic for various reasons. The article makes a case for a modular curriculum consisting of separate (i.e. non-integrated) task-based and structure-based components. Different curriculum models are considered in the light of what is known about how a second language is learned. The model that is proposed assumes the importance of developing fluency first. It consists of a primary task-based module implemented with focus-on-form (Long, 1991) and, once a basic fluency has been achieved, supported by a secondary structural module to provide for explicit accuracy-oriented work to counteract learned selective attention (N. Ellis, 2006): one of the main sources of persistent error. The article also addresses the content and grading of the task-based and structural modules. It considers the factors that need to be considered in the vertical and horizontal grading of tasks but also points out that, for the time being, syllabus designers will have to draw on their experience and intuition as much as on research to make decisions about how to sequence tasks. An argument is presented for treating the structural component as a checklist rather than as a syllabus so as to allow teachers to address selectively those features that are found to be problematic for their students when they perform tasks
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