Neutral perfect fluids of Majumdar-type in general relativity

We consider the extension of the Majumdar-type class of static solutions for the Einstein-Maxwell equations, proposed by Ida to include charged perfect fluid sources. We impose the equation of state $\rho+3p=0$ and discuss spherically symmetric solutions for the linear potential equation satisfied by the metric. In this particular case the fluid charge density vanishes and we locate the arising neutral perfect fluid in the intermediate region defined by two thin shells with respective charges $Q$ and $-Q$. With its innermost flat and external (Schwarzschild) asymptotically flat spacetime regions, the resultant condenser-like geometries resemble solutions discussed by Cohen and Cohen in a different context. We explore this relationship and point out an exotic gravitational property of our neutral perfect fluid. We mention possible continuations of this study to embrace non-spherically symmetric situations and higher dimensional spacetimes.Comment: 9 page

Runoff and erosion at the micro-plot and slope scale in a small burnt catchment, central Portugal

Wildfires can have important impacts on hydrological processes and soil erosion in forest catchments, due to the destruction of vegetation cover and changes to soil properties. However, the processes involved are non-linear and not fully understood. This has severely limited the understanding on the impacts of wildfires, especially in the up-scaling from hillslopes to catchments; in consequence, current models are poorly adapted for burnt forest conditions. The objective of this presentation is to give an overview of the hydrological response and sediment yield from the micro-plot to slope scale, in the first year following a wildfire (2008/2009) that burnt an entire catchment nearby the Colmeal village, central Portugal. The overview will focus on three slopes inside the catchment, with samples including: • Runoff at micro-plot scale (12 bounded plots) and slope scale (12 open plots); • Sediments and Organic Matter loss at micro-plot scale (12 bounded plots) and slope scale (12 open plots plus 3 Sediment fences); • Rainfall and Soil moisture data; • Soil Water Repellency and Ground Cover data. The analysis of the first year following the wildfire clearly shows the complexity of runoff generation and the associated sediment transport in recently burnt areas, with pronounced differences between hillslopes and across spatial scales as well as with marked variations through time. This work was performed in the framework of the EROSFIRE-II project (PTDC/AGR-CFL/70968/2006) which has as overall aim to predict soil erosion risk in recently burnt forest areas, including common post-fire forest management practices; the project focuses on the simultaneous measurement of runoff and soil erosion at multiple spatial scales.The results to be presented in this session are expected to show how sediment is generated, transported and exported in the Colmeal watershed; and contribute to understand and simulate erosion processes in burnt catchments, including for model development and evaluation

Development of a novel scheme for long-term body temperature monitoring: a review of benefits and applications

Body temperature is a health or disease marker that has been in clinical use for centuries. The threshold currently applied to define fever, with small variations, is 38 °C. However, current approaches do not provide a full picture of the thermoregulation process and its correlation with disease. This paper describes a new non-invasive body temperature device that improves the understanding of the pathophysiology of diseases by integrating a variety of temperature data from different body locations. This device enables to gain a deeper insight into fever, endogenous rhythms, subject activity and ambient temperature to provide anticipatory and more efficient treatments. Its clinical use would be a big step in the overcoming of the anachronistic febrile/afebrile dichotomy and walking towards a system medicine approach to certain diseases. This device has already been used in some clinical applications successfully. Other possible applications based on the device features and clinical requirements are also described in this paper.Cuesta Frau, D.; Varela Entrecanales, M.; Valor Pérez, R.; Vargas, B. (2015). Development of a novel scheme for long-term body temperature monitoring: a review of benefits and applications. Journal of Medical Systems. 39(4):1-7. doi:10.1007/s10916-015-0209-3S17394Gai, M., Merlo, I., Dellepiane, S., Cantaluppi, V., Leonardi, G., Fop, F., Guarena, C., Grassi, G., and Biancore, L., Glycemic pattern in diabetic patients on hemodialysis: Continuous Glucose Monitoring (CGM) analysis. Blood Purif. 38(1):68–73 , 2014.Kondziella, D., Friberg, C.K., Wellwood, I., Reiffurth, C., Fabricius, M., and Dreier, J.P.: Continuous EEG monitoring in aneurysmal subarachnoid hemorrhage: A systematic review. Neurocrit. Care (2014)Ciccone, A., Celani, M.G., Chiaramonte, R., Rossi, C., and Righetti, E., Continuous versus intermittent physiological monitoring for acute stroke. Cochrane Database Syst. Rev. 31, 2013.Kushimoto, S., Yamanouchi, S., Endo, T., Sato, T., Nomura, R., Fujita, M., Kudo, D., Omura, T., Miyagawa, N., and Sato, T., Body temperature abnormalities in non-neurological critically ill patients: A review of the literature. J. Intensive Care 2, 2014.Mc Callum, L., and Higgings, D., Measuring body temperature. Nursing Times 108:20–22, 2012.Varela, M., Ruiz-Esteban, R., Martinez-Nicolas, A., Cuervo-Arango, A., Barros, C., and Delgado, E.G., Catching the spike and tracking the flow: Holter-temperature monitoring in patients admitted in a general internal medicine ward. Int. J. Clin. Pract. 65(12):1283–1288, 2011.Lopes, F., Peres, D., Bross, A., Melot, C., and Vincent, J.L., Serial evaluation of the SOFA score to predict outcome in critically ill patients. J. Am. Med. Assoc. 286:1754–1758, 2001.Vincent, J.L., and Moreno, R., Clinical review: Scoring systems in the critically ill. Crit. Care, 14, 2010.Sund-Levander, M., and Grodzinsky, E., Time for a change to assess and evaluate body temperature in clinical practice. Int. J. Nurs. Pract. 15:241–249, 2009.Cuesta-Frau, D., Varela, M., Aboy, M., and Miro, P., Description of a portable wireless device for body temperature acquisition and analysis. Sensors 9(10):7648–7663, 2009.Varela, M., Cuesta-Frau, D., Madrid, J.A., Churruca, J., Miro-Matinez, P., Ruiz, R., and Marinez, C., Holter monitoring of central peripheral temperature: Possible uses and feasibility study in outpatient settings. J. Clin. Monit. Comput. 4(23):209–216, 2009.Jordan, J., Miro, P., Cuesta-Frau, D., Varela, M., and Vargas B.: Aplicacion de analisis multivariante para la deteccion de estados prefebriles en pacientes ingresados (in Spanish), XXXIV Congreso Nacional de Estadistica e Investigacion Operativa, Castellon (Spain) (2013)Richman, J., and Moorman, J.R., Physiological time-series analysis using approximate entropy and sample entropy. Am. J. Physiol. Heart Circ. Physiol. 278(6):H2039–2049, 2000.Young, P., Saxena, M., Eastwood, G.M., Bellomo, R., and Beasley, R., Fever and fever management among intensive care patients with known or suspected infection: A multicentre prospective cohort study. Crit. Care Resusc. 13:97–102 , 2011.Drewry, A.M., Fuller, B.M., Bailey, T.C., and Hotchkiss, R.S., Body temperature patterns as a predictor of hospital-acquired sepsis in afebrile adult intensive care unit patients: A case-control study. Crit. Care,17, 2013.Musher, D., Fainstein, V., Young, E., and Pruett, T., Fever patterns. Their lack of significance. Arch. Intern. Med. 139(11):1225–8, 1979.Varela, M., Calvo, M., Chana, M., Gomez-Mestre, I., Asensio, R., and Galdos, P., Clinical implications of temperature curve complexity in critically ill patients. Crit. Care Med. 33(12):2764–2771, 2005.Varela, M., Churruca, J., Gonzalez, A., Martin, A., Ode, J., and Galdos, P., Temperature curve complexity predicts survival in critically ill patients. Am. J. Respir. Crit. Care Med. 174(3):290–298, 2006.Cuesta-Frau, D., Varela, M., Miro, P., Galdos, P., Abasolo, D., Hornero, R., and Aboy, M., Predicting survival in critical patients by use of body temperature regularity measurement based on Approximate Entropy. Med. Biol. Eng. Computing 45:671–678, 2007.Mackiowak, P. Temperature regulation and the pathogenesis of fever, Principles and Practice of Infectious Diseases, pp. 765–778. New York: Churchill Livingston Elsevier, 2010.Cherbuin N., and Brinkman C., Cognition is cool: Can hemispheric activation be assessed by tympanic membrane thermometry? Brain Cogn. 54:228–231, 2004

Hydrological and erosion response at micro-plot to -catchment scale following forest wildfire, north-central Portugal

Wildfires can have important impacts on hydrological and soil erosion processes, due to the destruction of vegetation cover and changes to soil properties. According to Shakesby and Doerr (2006), these wildfire effects are: i) much better known at small spatial scales (especially erosion plots) than at the scale of catchments; ii) much better studied with respect to overland flow and streamflow (and, then, especially peak discharges) than to soil erosion. Following up on a precursor project studying runoff generation and the associated soil losses from micro-plot to slope-scale in Portuguese eucalypt forests, the EROSFIRE-II project addresses the connectivity of these processes across hillslopes as well as within the channel network. This is done in the Colmeal study area in central Portugal, where the outlet of an entirely burnt catchment of roughly 10 ha was instrumented with a gauging station continuously recording water level and tubidity, and five slopes were each equipped with 4 runoff plots of < 0,5 m2 (“micro-plot”) and 4 slope-scale plots as well as 1 slope-scale sediment fence. Starting one month after the August 2008 wildfire, the plots were monitored at 1- to 2-weekly intervals, depending on the occurrence of rainfall. The gauging station became operational at the end of November 2008, since the in-situ construction of an H-flume required several weeks. A preliminary analysis of the data collected till the end of 2008, focusing on two slopes with contrasting slope lengths as well as the gauging station: revealed clear differences in runoff and erosion between: (i) the micro-plot and slope-scale plots on the same hillslope; (ii) the two slopes; (iii) an initial dry period and a subsequent much wetter period; (iv) the slopes and the catchment-scale, also depending on the sampling period. These results suggest that the different processes govern the hydrological and erosion response at different spatial scales as well as for different periods, with soil water repellency playing a role during the initial post-fire period. The current presentation will review these preliminary results based on the data collected during the first year after the wildfire

The WINGS Survey: a progress report

A two-band (B and V) wide-field imaging survey of a complete, all-sky X-ray selected sample of 78 clusters in the redshift range z=0.04-0.07 is presented. The aim of this survey is to provide the astronomical community with a complete set of homogeneous, CCD-based surface photometry and morphological data of nearby cluster galaxies located within 1.5 Mpc from the cluster center. The data collection has been completed in seven observing runs at the INT and ESO-2.2m telescopes. For each cluster, photometric data of about 2500 galaxies (down to V~23) and detailed morphological information of about 600 galaxies (down to V~21) are obtained by using specially designed automatic tools. As a natural follow up of the photometric survey, we also illustrate a long term spectroscopic program we are carrying out with the WHT-WYFFOS and AAT-2dF multifiber spectrographs. Star formation rates and histories, as well as metallicity estimates will be derived for about 350 galaxies per cluster from the line indices and equivalent widths measurements, allowing us to explore the link between the spectral properties and the morphological evolution in high- to low-density environments, and across a wide range in cluster X-ray luminosities and optical properties.Comment: 12 pages, 10 eps figures, Proceedings of the SAIt Conference 200

Intelligent collaborative decision-making models, methods, and tools

[Excerpt] Problems in engineering are usually hard to be modeled and solved through mathematical approaches, due to the complex nature of these problems and the need for specifying efective, efcient, and proper models to consider and approach reallife or empirical and emulated problem scenarios. Many proposals are constantly being put forward, based on diferent kind of models, specially referring to mathematical models, and formalization approaches, in the context of this journal, ranging from purely linear programming models, algebra or diferential equations based models to artifcial intelligent (AI) oriented models or based on agents or neural networks. These include a great number of AI tools, such as fuzzy theory, grey theory, neural network model, Genetic Algorithms, and expert systems. [...