CFD of a hybrid cooling system composed of a displacement ventilation unit and a radiant cooling floor

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.The combined use of displacement ventilation (DV) [1-2] and a radiant cooling floor (RCF) [3-5] is increasingly common in the field of building climatization. DV systems are based on injecting air directly into the occupied zone of the building, at low speed and at a temperature slightly below the comfort one. On the other hand, RCF systems are based on circulating cold water through a circuit of pipes embedded in the pavement. With this hybrid cooling system (DV+RCF) that combines both technologies [6], only the occupied zone is climatizated and a vertical stratification of the room air temperature is achieved [7]. In addition, indoor air quality is greater than when conventional cooling systems are used [8], because the updraft convection currents caused by heat sources in the occupied zone [9], move the hot air and contaminants to the roof level going through the occupied zone only once. DV+RCF systems work better in building with high ceiling (of 3 meters high or more), where the air stratification will improve the thermal efficiency and pollution control. Therefore, its use is appropriate in large public buildings, for example theatres [10], museums [11], train stations [12] or airport terminals [13], which are characterized by their high rise. Despite the advantages of implementing a DV+RCF system, their behaviour is not well characterized for an efficient dimensioning of the system. Therefore, the aim of this paper is to present two correlations to quantify, on the one hand, the amount of energy (as heat) the floor is able to absorb by convection, that is, the heat flux along the floor, and, on the other hand, the maximum distance of influence of the primary air stream driven by the DV system. These correlations have been found for the hybrid cooling system DV+RCF in a large enclosure, using computational fluid dynamics (CFD). Moreover, they take into account the presence of the cooling floor and the vertical stratification of air temperature in the enclosure, becoming a powerful tool to help in the cooling system dimensioning. Multiple simulations with different Reynolds, based on the size of the diffuser and its supply air flow rate, and Grashof, based on the temperature difference between the floor and the air supplied by the diffuser, numbers were used to obtain the correlations.dc201

Implementation of an Artificial Neural Network on the Test Barcelona Workstation As a Predictive Model for the Classification of Normal, Mild Cognitive Impairment and Alzheimer’s Disease Subjects Using the Neuronorma Battery

Objective: To develop and implement an online Artificial Neural Network (ANN) that provides the probability of a subject having mild cognitive impairment (MCI) or Alzheimer’s disease (AD). Method: Different ANNs were trained using a sample of 350 controls (CONT), 75 MCI and 93 AD subjects. The ANN structure chosen was the following: (1) an input layer of 33 cognitive variables from the Neuronorma battery plus two sociodemographic variables, age and education. This layer was reduced to a 15 features input vector using Multiple Discriminant Analysis method, (2) one hidden layer with 8 neurons, and (3) three output neurons corresponding to the 3 expected cognitive states. This ANN was defined in a previous study [28]. The ANN was implemented on the web site www.test-barcelona.com (Test Barcelona Workstation) [9]. Results: When comparing CONT, MCI and AD participants, the best ANN correctly classifies up to 94,87% of the study participants. Conclusions: The online implemented ANN, delivers the probabilities (%) of belonging to the CONT, MCI and AD groups of a subject assessed using the 35 characteristics (variables) of the Neuronorma profile. This tool is a good complement for the interpretation of cognitive profiles. This technology improves clinical decision making. Keywords: Artificial Neural Network, Probability, Alzheimer disease, Test Barcelona Workstation

Neuropsychological Test Barcelona-2: Theoretical and Practical Aspects

The Barcelona test (TB) is an instrument of neuropsychological assessment, developed under the influence of Luria’s ideas, and published in 1990 [1]. It explores the main cognitive functions and allows the design of graphic profiles similar to those of the Boston Test for the diagnosis of aphasia. Objective: To present the theoretical and practical characteristics of a new version of the test, the Test Barcelona-2. The new and computerized versions of test structure is described here with six modules established: (1) Language-attention-orientation; (2) Reading and writing; (3) Motorpraxis; (4) Perception-gnosis; (5) Memory; (6) Abstraction-execution. As a novelty, test allows the selection for specific profiles: alpha, beta, abbreviated, aphasia, andecological-forensic approach. The types of variables condition a different statistical approach and a differentiated form of graphic expression. The new test presents a modular structure, which allows determining intra- and inter-module dissociations. Computerization greatly facilitates the work of the clinician. In the case of aphasia the test allows to differentiate easily all its clinical forms. Keywords: Test Barceona-2, neuropsychological test; computerized workstation, modular structur

Ischemic aetiology, self-reported frailty, and gender with respect to cognitive impairment in chronic heart failure patients

Background: decisive information on the parameters involved in cognitive impairment in patients with chronic heart failure is as yet lacking. Our aim was to determine the functional and psychosocial variables related with cognitive impairment using the mini-mental-state examination (MMSE) with age-and education-corrected scores. Methods: a cohort study of chronic heart failure patients included in an integrated multidisciplinary hospital/primary care program. The MMSE (corrected for age and education in the Spanish population) was administered at enrolment in the program. Analyses were performed in 525 patients. Demographic and clinical variables were collected. Comprehensive assessment included depression (Yesavage), family function (family APGAR), social network (Duke), dependence (Barthel Index), frailty (Barber), and comorbidities. Univariate and multivariate logistic regression were performed to determine the predictors of cognitive impairment. Results: cognitive impairment affected 145 patients (27.6 %). Explanatory factors were gender (OR: 2.77 (1.75-4.39) p  3.5 (OR: 0.59 (0.35-0.99) p = 0.048), and beta-blocker treatment (OR: 0.36 (0.17 to 0.76, p = 0.007)). No association was found between cognitive impairment and social support or family function. Conclusion: the observed prevalence of cognitive impairment using MMSE corrected scores was 27.6 %. A global approach in the management of these patients is needed, especially focusing on women and patients with frailty, low albumin levels, and ischemic aetiology heart failure

Recognition memory deficits in mild cognitive impairment

There is no agreement on the pattern of recognition memory deficits characteristic of patients diagnosed with mild cognitive impairment (Mel). Whereas lower performance in recollection is the hallmark of Mel, there is a strong controversy about possible deficits in familiarity estimates when using recognition memory tasks. The aim of this research is to shed Iight on the pattern of responding in recollection and familiarity in MCl. Five groups of participants were tested. The main participant samples were those formed by two Mel groups differing in age and an Alzheimer's disease group (AD), which were compared with two control groups, Whereas one of the control groups served to assess the performance of the MeI and AD people, the other one, composed of young healthy participants, served the purpose of evaluating the adequacy of the experimental tasks used in the evaluation of the different components of recognition memory. We used an associative recognition task as a direct index of recollection and a choice task on a pair of stimuli, one of which was perceptually similar to those studied in the associative recognition phase, as an index of familiarity. Our results indicate that recollection decreases with age and neurological status, and familiarity remains stable in the elderly control sample but it is deficient in Me!. This research shows that a unique encoding situation generated deficits in recollective and familiarity mechanisms in mild cognitive impaired individuals, providing evidence for the existence of deficits in both retrieval processes in recognition memory in a MeI stage

Ischemic aetiology, self-reported frailty, and gender with respect to cognitive impairment in chronic heart failure patients

Decisive information on the parameters involved in cognitive impairment in patients with chronic heart failure is as yet lacking. Our aim was to determine the functional and psychosocial variables related with cognitive impairment using the mini-mental-state examination (MMSE) with age-and education-corrected scores. A cohort study of chronic heart failure patients included in an integrated multidisciplinary hospital/primary care program. The MMSE (corrected for age and education in the Spanish population) was administered at enrolment in the program. Analyses were performed in 525 patients. Demographic and clinical variables were collected. Comprehensive assessment included depression (Yesavage), family function (family APGAR), social network (Duke), dependence (Barthel Index), frailty (Barber), and comorbidities. Univariate and multivariate logistic regression were performed to determine the predictors of cognitive impairment. Cognitive impairment affected 145 patients (27.6 %). Explanatory factors were gender (OR: 2.77 (1.75-4.39) p 3.5 (OR: 0.59 (0.35-0.99) p = 0.048), and beta-blocker treatment (OR: 0.36 (0.17 to 0.76, p = 0.007)). No association was found between cognitive impairment and social support or family function. The observed prevalence of cognitive impairment using MMSE corrected scores was 27.6 %. A global approach in the management of these patients is needed, especially focusing on women and patients with frailty, low albumin levels, and ischemic aetiology heart failure

A view of the Brazil-Malvinas confluence, March 2015

The encountering of the subtropical Brazil Current (BC) and the subantarctic Malvinas Current (MC) along the western margin of the Argentine Basin forms the Brazil-Malvinas Confluence (BMC), one of the most intense open-ocean fronts in the world ocean and a site for the formation of intermediate water masses. Here, we provide a comprehensive description of the BMC based on physical and biogeochemical data – hydrographic stations, profiling floats and subsurface drifters – gathered in March 2015. We use these data in order to characterize the impinging and outflowing currents and to describe the cross- and along-frontal thermohaline structure. In addition, we compare the in-situ measurements with both climatological data and the Mercator Ocean eddy-resolving reanalysis. The hydrographic sections illustrate the contrasting properties between the two western boundary currents: warm, salty, nutrient- and oxygen-poor oligotrophic subtropical waters carried southward by the BC and the cold, fresh, oxygen- and nutrient-rich subantarctic waters carried northward by the MC. The frontal system is also characterized by the presence of thermohaline intrusions, with the cross-frontal gradients and along-front velocities sharpening as the colliding currents shape the frontal system. We also observe brackish waters spreading on top of the frontal jet as a result of both the confluence dynamics and off-shelf advection favored by north-easterly winds. These low-salinity waters are positively correlated with surface ageostrophic speeds over the frontal jet. The cruise data illustrates the high regional and mesoscale variability as compared with climatological conditions, and further document the submesoscale subsurface complexity, which is not properly captured by available operational models.Fil: Orúe Echevarría, Dorleta. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Pelegrí, Josep L.. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Alonso González, Iván J.. Oceomic, Marine Bio And Technology S.L; EspañaFil: Benítez Barrios, Verónica M.. Oceomic, Marine Bio And Technology S.L; EspañaFil: Emelianov, Mikhail. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: García Olivares, Antonio. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Gasser i Rubinat, Marc. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: De La Fuente, Patricia. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Herrero, Carmen. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Isern Fontanet, Jordi. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Masdeu Navarro, Marta. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Peña Izquierdo, Jesús. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Piola, Alberto Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; ArgentinaFil: Ramírez Garrido, Sergio. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Rosell Fieschi, Miquel. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Salvador, Joaquín. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Saraceno, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Barcelona; EspañaFil: Valla, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Vallès Casanova, Ignasi. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; EspañaFil: Vidal, Montserrat. Universidad de Barcelona; Españ