63 research outputs found

    A CF3I-based SDD Prototype for Spin-independent Dark Matter Searches

    Full text link
    The application of Superheated Droplet Detectors (SDDs) to dark matter searches has so far been confined to the light nuclei refrigerants C2ClF5 and C4F10 (SIMPLE and PICASSO, respectively), with a principle sensitivity to spin-dependent interactions. Given the competitive results of these devices, as a result of their intrinsic insensitivity to backgrounds, we have developed a prototype trifluoroiodomethane (CF3I)-loaded SDD with increased sensitivity to spin-independent interactions as well. A low (0.102 kgd) exposure test operation of two high concentration, 1 liter devices is described, and the results compared with leading experiments in both spin-dependent and -independent sectors. Although competitive in both sectors when the difference in exposures is accounted for, a problem with fracturing of the detector gel must be addressed before significantly larger exposures can be envisioned.Comment: revised and updated; accepted Astrop. Phy

    IHE cross-enterprise document sharing for imaging: interoperability testing software

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>With the deployments of Electronic Health Records (EHR), interoperability testing in healthcare is becoming crucial. EHR enables access to prior diagnostic information in order to assist in health decisions. It is a virtual system that results from the cooperation of several heterogeneous distributed systems. Interoperability between peers is therefore essential. Achieving interoperability requires various types of testing. Implementations need to be tested using software that simulates communication partners, and that provides test data and test plans.</p> <p>Results</p> <p>In this paper we describe a software that is used to test systems that are involved in sharing medical images within the EHR. Our software is used as part of the Integrating the Healthcare Enterprise (IHE) testing process to test the Cross Enterprise Document Sharing for imaging (XDS-I) integration profile. We describe its architecture and functionalities; we also expose the challenges encountered and discuss the elected design solutions.</p> <p>Conclusions</p> <p>EHR is being deployed in several countries. The EHR infrastructure will be continuously evolving to embrace advances in the information technology domain. Our software is built on a web framework to allow for an easy evolution with web technology. The testing software is publicly available; it can be used by system implementers to test their implementations. It can also be used by site integrators to verify and test the interoperability of systems, or by developers to understand specifications ambiguities, or to resolve implementations difficulties.</p

    Bethe Ansatz solutions for highest states in N=4{\cal N}=4 SYM and AdS/CFT duality

    Get PDF
    We consider the operators with highest anomalous dimension Δ\Delta in the compact rank-one sectors su(11)\mathfrak{su}(1|1) and su(2)\mathfrak{su}(2) of N=4{\cal N}=4 super Yang-Mills. We study the flow of Δ\Delta from weak to strong 't Hooft coupling λ\lambda by solving (i) the all-loop gauge Bethe Ansatz, (ii) the quantum string Bethe Ansatz. The two calculations are carefully compared in the strong coupling limit and exhibit different exponents ν\nu in the leading order expansion Δλν\Delta\sim \lambda^{\nu}. We find ν=1/2\nu = 1/2 and ν=1/4\nu = 1/4 for the gauge or string solution. This strong coupling discrepancy is not unexpected, and it provides an explicit example where the gauge Bethe Ansatz solution cannot be trusted at large λ\lambda. Instead, the string solution perfectly reproduces the Gubser-Klebanov-Polyakov law Δ=2nλ1/4\Delta = 2\sqrt{n} \lambda^{1/4}. In particular, we provide an analytic expression for the integer level nn as a function of the U(1) charge in both sectors.Comment: 42 pages, JHEP style LaTe

    Designing Equitable Antiretroviral Allocation Strategies in Resource-Constrained Countries

    Get PDF
    BACKGROUND: Recently, a global commitment has been made to expand access to antiretrovirals (ARVs) in the developing world. However, in many resource-constrained countries the number of individuals infected with HIV in need of treatment will far exceed the supply of ARVs, and only a limited number of health-care facilities (HCFs) will be available for ARV distribution. Deciding how to allocate the limited supply of ARVs among HCFs will be extremely difficult. Resource allocation decisions can be made on the basis of many epidemiological, ethical, or preferential treatment priority criteria. METHODS AND FINDINGS: Here we use operations research techniques, and we show how to determine the optimal strategy for allocating ARVs among HCFs in order to satisfy the equitable criterion that each individual infected with HIV has an equal chance of receiving ARVs. We present a novel spatial mathematical model that includes heterogeneity in treatment accessibility. We show how to use our theoretical framework, in conjunction with an equity objective function, to determine an optimal equitable allocation strategy (OEAS) for ARVs in resource-constrained regions. Our equity objective function enables us to apply the egalitarian principle of equity with respect to access to health care. We use data from the detailed ARV rollout plan designed by the government of South Africa to determine an OEAS for the province of KwaZulu–Natal. We determine the OEAS for KwaZulu–Natal, and we then compare this OEAS with two other ARV allocation strategies: (i) allocating ARVs only to Durban (the largest urban city in KwaZulu–Natal province) and (ii) allocating ARVs equally to all available HCFs. In addition, we compare the OEAS to the current allocation plan of the South African government (which is based upon allocating ARVs to 17 HCFs). We show that our OEAS significantly improves equity in treatment accessibility in comparison with these three ARV allocation strategies. We also quantify how the size of the catchment region surrounding each HCF, and the number of HCFs utilized for ARV distribution, alters the OEAS and the probability of achieving equity in treatment accessibility. We calculate that in order to achieve the greatest degree of treatment equity for individuals with HIV in KwaZulu–Natal, the ARVs should be allocated to 54 HCFs and each HCF should serve a catchment region of 40 to 60 km. CONCLUSION: Our OEAS would substantially improve equality in treatment accessibility in comparison with other allocation strategies. Furthermore, our OEAS is extremely different from the currently planned strategy. We suggest that our novel methodology be used to design optimal ARV allocation strategies for resource-constrained countries

    New living evidence resource of human and non-human studies for early intervention and research prioritisation in anxiety, depression and psychosis

    Get PDF
    In anxiety, depression and psychosis, there has been frustratingly slow progress in developing novel therapies that make a substantial difference in practice, as well as in predicting which treatments will work for whom and in what contexts. To intervene early in the process and deliver optimal care to patients, we need to understand the underlying mechanisms of mental health conditions, develop safe and effective interventions that target these mechanisms, and improve our capabilities in timely diagnosis and reliable prediction of symptom trajectories. Better synthesis of existing evidence is one way to reduce waste and improve efficiency in research towards these ends. Living systematic reviews produce rigorous, up-to-date and informative evidence summaries that are particularly important where research is emerging rapidly, current evidence is uncertain and new findings might change policy or practice. Global Alliance for Living Evidence on aNxiety, depressiOn and pSychosis (GALENOS) aims to tackle the challenges of mental health science research by cataloguing and evaluating the full spectrum of relevant scientific research including both human and preclinical studies. GALENOS will also allow the mental health community-including patients, carers, clinicians, researchers and funders-to better identify the research questions that most urgently need to be answered. By creating open-access datasets and outputs in a state-of-the-art online resource, GALENOS will help identify promising signals early in the research process. This will accelerate translation from discovery science into effective new interventions for anxiety, depression and psychosis, ready to be translated in clinical practice across the world

    New living evidence resource of human and non-human studies for early intervention and research prioritisation in anxiety, depression and psychosis

    Get PDF
    In anxiety, depression and psychosis, there has been frustratingly slow progress in developing novel therapies that make a substantial difference in practice, as well as in predicting which treatments will work for whom and in what contexts. To intervene early in the process and deliver optimal care to patients, we need to understand the underlying mechanisms of mental health conditions, develop safe and effective interventions that target these mechanisms, and improve our capabilities in timely diagnosis and reliable prediction of symptom trajectories. Better synthesis of existing evidence is one way to reduce waste and improve efficiency in research towards these ends. Living systematic reviews produce rigorous, up-to-date and informative evidence summaries that are particularly important where research is emerging rapidly, current evidence is uncertain and new findings might change policy or practice. Global Alliance for Living Evidence on aNxiety, depressiOn and pSychosis (GALENOS) aims to tackle the challenges of mental health science research by cataloguing and evaluating the full spectrum of relevant scientific research including both human and preclinical studies. GALENOS will also allow the mental health community-including patients, carers, clinicians, researchers and funders-to better identify the research questions that most urgently need to be answered. By creating open-access datasets and outputs in a state-of-the-art online resource, GALENOS will help identify promising signals early in the research process. This will accelerate translation from discovery science into effective new interventions for anxiety, depression and psychosis, ready to be translated in clinical practice across the world

    Riesgo cardiovascular en estudiantes de medicina del municipio Puerto Padre de Las Tunas

    Get PDF
    Introduction: cardiovascular diseases are the first cause of death in Cuba; as a result, the identification of cardiovascular risks from early ages allows the implementation of health promotion and prevention strategies to reduce their impact in the futureObjective: to identify the cardiovascular risk in medical students in Puerto Padre Municipality, Las Tunas province.Methods: an observational, descriptive and cross-sectional study was conducted. The target group included 545 medical students, 237 of whom were selected by means of a simple random sample. The body mass index and waist-hip ratio were studied. Descriptive statistics was applied.Results: the predominant age group was 18-21 years old (50,2 %). The 51,47 % of the students presented a high waist-hip ratio, 54,02 % a high abdominal circumference, 52,74 % a high body mass index, and in all groups 35,44 % presented blood pressure figures lower than 120/80 mmHg; 39 % had a cardiovascular risk.Conclusions: low percentages of cardiovascular risk were identified in medical students from Puerto Padre Municipality, Las Tunas province, determined by high values of waist-hip index, body mass index and abdominal circumference.Introducción: las enfermedades cardiovasculares constituyen la primera causa de mortalidad en Cuba; por lo cual la identificación de riesgos cardiovasculares desde edades tempranas permite implementar estrategias de promoción y prevención de salud para disminuir su impacto en el futuroObjetivo: identificar el riesgo cardiovascular en estudiantes de medicina del municipio Puerto Padre de Las Tunas.Método: se realizó un estudio observacional, descriptivo y transversal. El universo estuvo constituido por 545 estudiantes de medicina, seleccionándose 237 mediante un muestreo aleatorio simple. Se estudió el índice de masa corporal, la circunferencia abdominal y la índice cintura cadera. Se empleó estadística descriptiva.Resultados: se encontró predominio del grupo etario de 18 a 21 años (50,2 %). El 51,47 % de los estudiantes presentó un índice cintura-cadera alto, el 54,02 % una circunferencia abdominal alta, el 52,74 % un índice de masa corporal alta, así como en todos los grupos el 35,44 % presentó cifras de tensión arterial inferiores a 120/80 mmHg. El 39 % presentó riesgo cardiovascular.Conclusiones: se identificaron bajos porcientos de riesgo cardiovascular en los estudiantes de medicina del municipio Puerto Padre de Las Tunas, determinado por altos valores los índice cintura-cadera, índice de masa corporal y circunferencia abdominal
    corecore