Tracking Cluster Debris (TraCD) – I. Dissolution of clusters and searching for the solar cradle

The capability to reconstruct dissolved stellar systems in dynamical and chemical space is a key factor in improving our understanding of the evolution of the Milky Way. Here we concentrate on the dynamical aspect and given that a significant portion of the stars in the Milky Way have been born in stellar associations or clusters that have lived a few Myr up to several Gyr, we further restrict our attention to the evolution of star clusters. We have carried out our simulations in two steps: (1) we create a simulation of dissolution and mixing processes which yields a close fit to the present-day Milky Way dynamics and (2) we have evolved three sets of stellar clusters with masses of 400, 1000 and 15 000 M⊙ to dissolution. The birth location of these sets was 4, 6, 8 and 10 kpc for the 400 and 1000 M⊙ clusters and 4, 6, 8, 10 and 12 kpc for the 15 000 M⊙. We have focused our efforts on studying the state of the escapers from these clusters after 4.5 Gyr of evolution with particular attention to stars that reach the solar annulus, i.e. 7.5 ≤ Rgc ≤ 8.5 kpc. We give results for solar twins and siblings over a wide range of radii and cluster masses for two dissolution mechanisms. From kinematics alone, we conclude that the Sun was ∼50 per cent more likely to have been born near its current Galactocentric radius, rather than have migrated (radially) ∼2 kpc since birth. We conclude our analysis by calculating magnitudes and colours of our single stars for comparison with the samples that the Gaia, Gaia-ESO and GALAH-AAO surveys will obtain. In terms of reconstructing dissolved star clusters, we find that on short time-scales we cannot rely on kinematic evolution alone and thus it will be necessary to extend our study to include information on chemical space

An object-oriented framework for predictive models in intensive care units

When used in conjunction with patterns, class libraries, and components, objectoriented application frameworks can significantly increase software quality and reduce development effort. Frameworks are a kind of domain-specific model whose structure can reuse existing patterns. In the field of medical applications, one of the important trends is the move towards frameworks describing different situations. Frameworks in medicine entails capturing, storing, retrieving, transmitting and manipulating patient-specific health care related data, including clinical, administrative, and biographical data. Using predictive methods in Intensive Care Units is a standard procedure to determine a measure of disease severity, based on current physiologic measurements, age and previous health condition. These situations can be described by reusing existing models and patterns, and building new structures based on flexible issues. In this paper, we present a Java object-oriented framework developed for modelling predictive methods in Intensive Care Units. We also briefly discuss future work, which will include a formal specification as part of the framework’s documentation.Eje: Ingeniería de softwareRed de Universidades con Carreras en Informática (RedUNCI

Conservación de recursos a través de estrategias de reutilización de edificios y de reutilización de materiales en el sitio

Rethinking buildings and construction activities is a fundamental step towards sustainable construction. Being one of the most materials consumers, changes to current practices in the construction industry are crucial in order to effectively reduce primary resources exploitation, as also to reduce the environmental impacts associated with it. End of life of buildings are opportunities to close the materials loop, by means of building renewal and recovery of components and materials. In this context, building reuse and on site materials reuse have shown to be the most preferable end of life scenarios when compared with off site reuse, recycling, energy recovery and landfill disposal. Moving from demolition to deconstruction is one of the changes that are supposed to happen. Another is to change the materials selection procedures in order to consider also reused materials as a valid option in architectural process. Therefore, surveys to assess reuse potential are needed prior to architectural design in order to look for reuse opportunities and reuse constrains both at the building level and materials level. Such opportunities and constrains comprise building adaptability, building conservation state, mechanical and aesthetic performance of materials, feasibility of components and materials recovery. However, existing buildings were not built to be deconstructed and materials recovery is a labor intensive task, facing obstacles as non reversible connections which usually destroy materials integrity. A case study for building reuse and on site materials reuse is here analised in order to illustrate the theoretical principles and goals that drive the reuse approach, highlighting the environmental benefits by keeping Embodied Energy and thus reducing the Global Warming Potential related to construction activitiesRepensar los edificios y las actividades de la construcción es un paso fundamental hacia la construcción sostenible. Siendo uno de los mayores consumidores de materiales, es crucial proceder a cambios en las prácticas actuales en el sector de la construcción para reducir efectivamente la explotación de recursos primarios, como también para reducir todos los impactos ambientales asociados. El fin de vida de los edificios son oportunidades para cerrar el ciclo de vida de los materiales, por medio de la renovación de los edificios y la recuperación de componentes y materiales. En este contexto, la reutilización de los edificios y la reutilización de los materiales en el sitio han demostrado ser la solución más preferible en la gestión de los escenarios de fin de ciclo de vida, en comparación con la reutilización de los materiales fuera del sitio, reciclaje, valorización energética y eliminación en vertedero. Pasar de la demolición a la deconstrucción es uno de los cambios que deberá de acontecer. Otro es lo de cambiar los procedimientos de selección de los materiales con el fin de tener en cuenta también los materiales reutilizables como una opción válida en el proyecto arquitectónico. Por lo tanto, se necesita estudiar el edificio para evaluar su potencial de reutilización antes del proyecto, con el fin de buscar oportunidades y restricciones a la reutilización, tanto al nivel del edificio como al nivel de los componentes y materiales. Tales oportunidades y limitaciones incluyen la capacidad de adaptación del edificio, su estado de conservación, el funcionamiento mecánico y condición estética de los materiales y, por fin, la viabilidad técnica y económica de la recuperación de esos componentes y materiales. Sin embargo, los edificios existentes no fueron construidos para seren deconstruidos y la recuperación de materiales se torna una tarea intensiva de trabajo, enfrentando obstáculos como conexiones no reversibles que normalmente destruyen la integridad de los materiales. Un caso de estudio para la reutilización de la construcción y la reutilización de materiales en el sitio está aquí analizado con el fin de ilustrar los principios y objetivos teóricos que impulsan el enfoque de la reutilización, destacando los beneficios ambientales al mantener la energía incorporada y reduciendo así el potencial de calentamiento global relacionado con las actividades de construcción

Non-extensive entropy from incomplete knowledge of Shannon entropy?

In this paper we give an interpretation of Tsallis' nonextensive statistical mechanics based upon the information-theoretic point of view of Luzzi et al. [cond-mat/0306217; cond-mat/0306247; cond-mat/0307325], suggesting Tsallis' entropy to be not a fundamental concept but rather a derived one, stemming from an incomplete knowledge of the system, not taking properly into account its interaction with the environment. This interpretation seems to avoid some problems occurring with the original interpretation of Tsallis statistics.Comment: v.4. 11 pages. Title changed. Content substantially changed: added discussion of several points raised by various referees and readers; Also reference made to work by Luzzi, Vasconcellos, Galvao Ramos. Physica Scripta, to appea

When do generalized entropies apply? How phase space volume determines entropy

We show how the dependence of phase space volume $\Omega(N)$ of a classical system on its size $N$ uniquely determines its extensive entropy. We give a concise criterion when this entropy is not of Boltzmann-Gibbs type but has to assume a {\em generalized} (non-additive) form. We show that generalized entropies can only exist when the dynamically (statistically) relevant fraction of degrees of freedom in the system vanishes in the thermodynamic limit. These are systems where the bulk of the degrees of freedom is frozen and is practically statistically inactive. Systems governed by generalized entropies are therefore systems whose phase space volume effectively collapses to a lower-dimensional 'surface'. We explicitly illustrate the situation for binomial processes and argue that generalized entropies could be relevant for self organized critical systems such as sand piles, for spin systems which form meta-structures such as vortices, domains, instantons, etc., and for problems associated with anomalous diffusion.Comment: 5 pages, 2 figure

Numerical indications of a q-generalised central limit theorem

We provide numerical indications of the $q$-generalised central limit theorem that has been conjectured (Tsallis 2004) in nonextensive statistical mechanics. We focus on $N$ binary random variables correlated in a {\it scale-invariant} way. The correlations are introduced by imposing the Leibnitz rule on a probability set based on the so-called $q$-product with $q \le 1$. We show that, in the large $N$ limit (and after appropriate centering, rescaling, and symmetrisation), the emerging distributions are $q_e$-Gaussians, i.e., $p(x) \propto [1-(1-q_e) \beta(N) x^2]^{1/(1-q_e)}$, with $q_e=2-\frac{1}{q}$, and with coefficients $\beta(N)$ approaching finite values $\beta(\infty)$. The particular case $q=q_e=1$ recovers the celebrated de Moivre-Laplace theorem.Comment: Minor improvements and corrections have been introduced in the new version. 7 pages including 4 figure

Managerial family ties and employee risk bearing in family firms : evidence from Spanish car dealers

The paper argues that family firms in which the Top Management Team (TMT) is dominated by non-family managers are more likely to shift risk to employees through incentive pay schemes than family firms with TMTs dominated by family members. We also argue that this tendency is aggravated in firms of bigger size as this condition makes non-family managers more vulnerable. We further note that differences between family and non-family dominated TMTs may lessen when the sales trend is negative. The analyses conducted on a sample of 219 family controlled car dealerships in Spain confirm our expectations

Estudio descriptivo de establecimientos farmacéuticos en Bogotá D.C. y del personal responsable de la atención a usuarios localidad nº 11 Suba

Encuestas, Tablas, Imágenes, Mapa Geográfico y GraficasSe evaluaron los diferentes establecimientos inscritos en las entidades antes mencionadas, de una total de 3.707 establecimientos farmacéuticos en Secretaria de Salud y 2.942 en Cámara y comercio en Bogotá se tomó para el trabajo de la localidad de Suba, 361 inscritos en Secretaria de Salud y 499 de Cámara de comercio que corresponden a un 9.7% y un 17% del total de Bogotá, de allí se obtuvo una muestra de 34 establecimientos de Secretaría de Salud y 58 establecimientos de cámara y comercio, del total de la base de datos proporcionada por la secretaria de salud y cámara y comercio, para el muestreo se contó con el apoyo de la Unidad de Ciencias Básicas de la Universidad Nacional Abierta y a Distancia (UNAD) y para la aplicación de la encuesta con los estudiantes de ultimo semestre de Regencia de Farmacia; En el momento de la encuesta se excluyeron los establecimientos que no eran considerados farmacéuticos como tiendas naturistas, pañaleras y tiendas cosméticas entre otros . De los establecimientos farmacéuticos encuestados seleccionados se hizo efectiva la encuesta en 50.1% de los establecimientos, encontrándose que en 6.3% correspondían a establecimientos a los que no aplicaba la encuesta y el 43.8% eran establecimientos que no existían en las direcciones relacionadas, para un promedio total de 8 establecimientos. Estos resultados permiten observar en forma mas clara el cumplimiento de las normas a nivel general y la manera como se están aplicando.For this the different establishments enrolled in the organizations before mentioned were evaluated, of a total of 3,707 pharmaceutical establishments in Secretary of Health and 2,942 in Camera and commerce in Bogotá were taken for the work of the locality from Raises, the pertaining ones to the locality that correspond to 361 enrolled ones in Secretary of Health and 499 of Chamber of Commerce which a 17% of the total of Bogotá correspond to 9,7% and, obtained a sample of 34 establishments of Secretariat of Health and 58 establishments of camera there and commerce, of the total of the data base provided by the secretary of health and camera and commerce, for sampling was counted on the support of the Unit of Basic Sciences of the Opened National University and remote (UNAD) and for the application of the survey with the students of I complete semester of Regency of Pharmacy. at the moment of the survey the establishments that were not considered drug stores like natural stores, baby’s store and cosmetic stores among others were excluded Of the pharmaceutical polled selected establishments the survey became effective in 50.1 % of the establishments, thinking that in 6.3 % they were corresponding(fitting) to establishments to which it(he,she) was not applying the survey and 43.8 % they were establishments that did not exist in the related directions(addresses), for a total average of 8 establishments. These results allow to observe in form mas clear the fulfillment of the procedure to general level and the way like are applying

Market impact and trading profile of large trading orders in stock markets

We empirically study the market impact of trading orders. We are specifically interested in large trading orders that are executed incrementally, which we call hidden orders. These are reconstructed based on information about market member codes using data from the Spanish Stock Market and the London Stock Exchange. We find that market impact is strongly concave, approximately increasing as the square root of order size. Furthermore, as a given order is executed, the impact grows in time according to a power-law; after the order is finished, it reverts to a level of about 0.5-0.7 of its value at its peak. We observe that hidden orders are executed at a rate that more or less matches trading in the overall market, except for small deviations at the beginning and end of the order.Comment: 9 pages, 7 figure