2,707 research outputs found
Sustainable Conversion of historic buildings in Cuba: the case of Santo Domingo de Atares Castle, Havana
Recently, in the Cuban capital of Havana, a number of fortresses were given away by the Army for refurbishment and conversion to public functions. In the last two decades, there have been examples of refurbishment and conversions of fortifications in museums, some of them with dire consequences for the collections and the structures. In this type of structure every architectonical element has historic value and very few interventions are allowed. However, the accommodation of modern functions and the preservation of the structure heavily rely upon the balance between various environmental parameters of the interior spaces. This study explores the challenges and opportunities of an environmentally driven conservation approach to the refurbishment of one of Havana’s most iconic XVIII century’s defensive structures, Santo Domingo of Atares Castle. The paper illustrates the development of an architectural proposal for the conversion of the castle into a museum and associated energy and environmental strategies. The museum function is particularly demanding due to the rigorous standards for the preservation of the collections, generally accomplished by mechanical equipment. Recently, however, there has been a major concern in the conservation scene about energy consumption and sustainable practices in this type of buildings. Therefore, the work identifyies the characteristics of the existing climatic and environmental conditions affecting the interior spaces of the thermally heavyweight fortress. This has led to an analysis of the requirements of the collection in a hot-humid climate in conjunction with the parameters for human comfort, in order to identify to what extent the original conditions can be passively modified to adapt the building to the conversion. Finally, with the help of computational dynamic simulations, passive strategies and zoning options were tested for the achievement of suitable interior environmental conditions and subsequent energy savings
Micromagnetism in (001) magnetite by spin-polarized low-energy electron microscopy
Spin-polarized low-energy electron microscopy was used to image a magnetite
crystal with (100) surface orientation. Sets of spin-dependent images of
magnetic domain patterns observed in this surface were used to map the
direction of the magnetization vector with high spatial and angular resolution.
We find that domains are magnetized along the surface [110] directions, and
domain wall structures include 90{\deg} and 180{\deg} walls. A type of
unusually curved domain walls are interpreted as N\'eel-capped surface
terminations of 180{\deg} Bloch walls.Comment: 17 pages, 4 figures. Presented at the LEEM-PEEM 8 conferenc
Theory and simulation of the dynamics, deformation, and breakup of a chain of superparamagnetic beads under a rotating magnetic field
In this work, an analytical model for the behavior of superparamagnetic chains under the effect of a rotating magnetic field is presented. It is postulated that the relevant mechanisms for describing the shape and breakup of the chains into smaller fragments are the induced dipole-dipole magnetic force on the external beads, their translational and rotational drag forces, and the tangential lubrication between particles. Under this assumption, the characteristic S-shape of the chain can be qualitatively understood. Furthermore, based on a straight chain approximation, a novel analytical expression for the critical frequency for the chain breakup is obtained. In order to validate the model, the analytical expressions are compared with full three-dimensional smoothed particle hydrodynamics simulations of magnetic beads showing excellent agreement. Comparison with previous theoretical results and experimental data is also reported
Determination of the cosmic-ray-induced neutron flux and ambient dose equivalent at flight altitude
Journal of Physics: Conference Series, Volumen 630There is interest in modeling the atmosphere in the South Atlantic Magnetic Anomaly in order to obtain information about the cosmic-ray induced neutron spectrum and angular distribution as functions of altitude. In this work we use the Monte Carlo codes MCNPX and Geant4 to determine the cosmic-ray-induced neutron flux in the atmosphere produced by the cosmic ray protons incident on the top of the atmosphere and to estimate the ambient dose equivalent rate as function of altitude. The results present a reasonable conformity to other codes (QARM and EXPACS) based on other parameterizations
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The development of 'Make One Small Change': an e-health intervention for the workplace developed using the Person-Based Approach.
Background: The application of digital health interventions is widespread and many employers are implementing employee e-health programs. Intended to enhance productivity by increasing wellbeing, workplace interventions often lack evidence of effectiveness and have low rates of retention. Use of the person-based approach (PBA) is one solution, which offers a systematic framework for developing effective digital health interventions. This paper describes the application of the PBA to the development of 'Make one small change' (Cigna MSC™), an online behaviour change system for lifestyle habits focused on resilience, movement, eating and sleep. Method and results: The development of Cigna MSC™ took place over four stages with colleagues (n = 79) across Cigna globally. Application of the PBA entailed using high amounts of qualitative data to inform development and a cyclical process of 'listening, applying and delivering' was adhered to throughout. Early stages involved review of current literature and the collection of feedback in relation to existing interventions. Combined, results revealed key intervention development issues that were then used to form guiding principles. Guiding principles ensured intervention objectives translated into relevant design features. The final stages of evaluation included testing images, text and content approaches. Feedback dictated that the intervention should be fun, easy to use and include milestones for self-monitoring. The resulting version was finalised and made ready to pilot so future analysis can be made in relation to real-world engagement and the embedded evaluative content can be used to provide evidence of intervention effectiveness. Conclusions: Using the PBA, which was evolved specifically to improve development of digital interventions, resulted in a workplace intervention embedded with in-depth user input combined with evidenced-based theory. This paper illustrates how using a rigorous methodology can drive the creation of an effective digital health intervention that uniquely allows for refinement at each stage
Anion transport and supramolecular medicinal chemistry
New approaches to the transmembrane transport of anions are discussed in this review. Advances in the design of small molecule anion carriers are reviewed in addition to advances in the design of synthetic anion channels. The application of anion transporters to the potential future treatment of disease is discussed in the context of recent findings on the selectivity of anion transporters.University of Sydney and the Australian Research
Council (DP170100118) for funding. JTD thanks the Office of Basic
Energy Sciences, U.S. Department of Energy (DE-FG02-98ER14888)
for funding. RQ thanks Consejerı´a de Educacio´n de la Junta de
Castilla y Leo´n (BU340U13 and BU092U16) and La Marato´ de TV3
Foundation (20132730
Hydrogen-induced reversible spin-reorientation transition and magnetic stripe domain phase in bilayer Co on Ru(0001)
Imaging the change in the magnetization vector in real time by spin-polarized
low-energy electron microscopy, we observed a hydrogen-induced, reversible
spin-reorientation transition in a cobalt bilayer on Ru(0001). Initially,
hydrogen sorption reduces the size of out-of-plane magnetic domains and leads
to the formation of a magnetic stripe domain pattern, which can be understood
as a consequence of reducing the out-of-plane magnetic anisotropy. Further
hydrogen sorption induces a transition to an in-plane easy-axis. Desorbing the
hydrogen by heating the film to 400 K recovers the original out-of-plane
magnetization. By means of ab-initio calculations we determine that the origin
of the transition is the local effect of the hybridization of the hydrogen
orbital and the orbitals of the Co atoms bonded to the absorbed hydrogen.Comment: 5 figure
Autoimmune rheumatic diseases : An update on the role of atherogenic electronegative ldl and potential therapeutic strategies
Altres ajuts: Vascular and Medicinal Research Fund, Texas Heart Institute (#765-64050), Houston, TX, USA; Ministry of Science and Technology (Taiwana grant MOST 107-2314-B-039-053-MY3); Ministerio de Sanidad, Spain (co-financed by Fondo Europeo de Desarrollo Regional (FEDER)).Atherosclerosis has been linked with an increased risk of atherosclerotic cardiovascular disease (ASCVD). Autoimmune rheumatic diseases (AIRDs) are associated with accelerated atherosclerosis and ASCVD. However, the mechanisms underlying the high ASCVD burden in patients with AIRDs cannot be explained only by conventional risk factors despite disease-specific factors and chronic inflammation. Nevertheless, the normal levels of plasma low-density lipoprotein (LDL) cholesterol observed in most patients with AIRDs do not exclude the possibility of increased LDL atherogenicity. By using anion-exchange chromatography, human LDL can be divided into five increasingly electronegative subfractions, L1 to L5, or into electropositive and electronegative counterparts, LDL (+) and LDL (−). Electronegative L5 and LDL (−) have similar chemical composi-tions and can induce adverse inflammatory reactions in vascular cells. Notably, the percentage of L5 or LDL (−) in total LDL is increased in normolipidemic patients with AIRDs. Electronegative L5 and LDL (−) are not recognized by the normal LDL receptor but instead signal through the lectin-like oxidized LDL receptor 1 (LOX-1) to activate inflammasomes involving interleukin 1β (IL-1β). Here, we describe the detailed mechanisms of AIRD-related ASCVD mediated by L5 or LDL (−) and discuss the potential targeting of LOX-1 or IL-1β signaling as new therapeutic modalities for these diseases
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