1,200 research outputs found
Implantes transcigomáticos
Los implantes cigomáticos, originariamente diseñados por Branemark en 1989, son implantes de cabeza en 45 grados, de 4'5 milÃmetros de diámetro en su parte más ancha, y que pueden medir entre 30 y 50 milÃmetros de longitud. Se insertan desde la parte palatina del proceso alveolar, siguiendo la cresta cigomática-alveolar hasta anclarse en el cuerpo del malar, y en el caso de pacientes maxilectomizados, entrando directamente en el cuerpo del malar. Estos implantes ofrecen una alternativa más al cirujano en el momento de planificar un tratamiento protésico-rehabilitador implantosoportado. Sobretodo, en aquellos pacientes con un maxilar superior atrófico en el que no se pueden realizar injertos óseos o estos han fracasado. El objetivo de este artÃculo es proponer el protocolo quirúrgico de colocación de los implantes trascigomáticos y revisar la literatura actual sobre la evolución clÃnica de estos implantes
Developing Intensity-Duration-Frequency (IDF) Curves From Satellite-Based Precipitation: Methodology and Evaluation
Given the continuous advancement in the retrieval of precipitation from satellites, it is important to develop methods that incorporate satellite-based precipitation data sets in the design and planning of infrastructure. This is because in many regions around the world, in situ rainfall observations are sparse and have insufficient record length. A handful of studies examined the use of satellite-based precipitation to develop intensity-duration-frequency (IDF) curves; however, they have mostly focused on small spatial domains and relied on combining satellite-based with ground-based precipitation data sets. In this study, we explore this issue by providing a methodological framework with the potential to be applied in ungauged regions. This framework is based on accounting for the characteristics of satellite-based precipitation products, namely, adjustment of bias and transformation of areal to point rainfall. The latter method is based on previous studies on the reverse transformation (point to areal) commonly used to obtain catchment-scale IDF curves. The paper proceeds by applying this framework to develop IDF curves over the contiguous United States (CONUS); the data set used is Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks – Climate Data Record (PERSIANN-CDR). IDFs are then evaluated against National Oceanic and Atmospheric Administration (NOAA) Atlas 14 to provide a quantitative estimate of their accuracy. Results show that median errors are in the range of (17–22%), (6–12%), and (3–8%) for one-day, two-day and three-day IDFs, respectively, and return periods in the range (2–100) years. Furthermore, a considerable percentage of satellite-based IDFs lie within the confidence interval of NOAA Atlas 14
PLA scaffolds production from Thermally Induced Phase Separation: effect of process parameters and development of an environmentally improved route assisted by supercritical carbon dioxide
In this work, a relatively large scale of PLA scaffolds was produced using thermally induced phase separation (TIPS) combined with a supercritical carbon dioxide (SC-CO2) drying step as a green alternative. For the TIPS step, the phase separation of PLA and 1,4-dioxane solvent was controlled by adjusting the process conditions such as the polymer concentration and molecular weight, the 1,4-dioxane solvent power and the cooling conditions. The scaffolds morphology was analyzed by scanning electron microscopy. Their structural and mechanical properties were correlated together with the possibility to tune them by controlling the process conditions. An environmental analysis using the Life Cycle Assessment (LCA) methodology confirmed a reduction of at least 50% of the environmental impact of the whole process using the SC-CO2 drying compared to the traditional freeze-drying technology. This work is the first known attempt to conduct the LCA methodology on TIPS process for the PLA scaffolds production
Porosity measurements of interstellar ice mixtures using optical laser interference and extended effective medium approximations
Aims. This article aims to provide an alternative method of measuring the
porosity of multi-phase composite ices from their refractive indices and of
characterising how the abundance of a premixed contaminant (e.g., CO2) affects
the porosity of water-rich ice mixtures during omni-directional deposition.
Methods. We combine optical laser interference and extended effective medium
approximations (EMAs) to measure the porosity of three astrophysically relevant
ice mixtures: H2O:CO2=10:1, 4:1, and 2:1. Infrared spectroscopy is used as a
benchmarking test of this new laboratory-based method. Results. By
independently monitoring the O-H dangling modes of the different water-rich ice
mixtures, we confirm the porosities predicted by the extended EMAs. We also
demonstrate that CO2 premixed with water in the gas phase does not
significantly affect the ice morphology during omni-directional deposition, as
long as the physical conditions favourable to segregation are not reached. We
propose a mechanism in which CO2 molecules diffuse on the surface of the
growing ice sample prior to being incorporated into the bulk and then fill the
pores partly or completely, depending on the relative abundance and the growth
temperature.Comment: 9 pages, 6 figures, 1 table. Accepted for publication in A&
Diagnosis of disseminated toxoplasmosis by PCR analysis of ascitic fluid in a patient with haematologic malignancy
TLR3 MATURATION, LOCALISATION AND APOPTOTIC ROLE IN CANCER
Oral Communication presented at the ";Forum des Jeunes Chercheurs";, Brest (France) 2011
Structural coronary artery remodelling in the rabbit fetus as a result of intrauterine growth restriction
Intrauterine growth restriction (IUGR) is a fetal condition that affects up to 10% of all pregnancies and is associated with cardiovascular structural and functional remodelling that persists postnatally. Some studies have reported an increase in myocardial coronary blood flow
in severe IUGR fetuses which has been directly associated to the dilatation of the coronary
arteries. However, a direct measurement of the coronaries’ lumen diameter in IUGR has not
been reported before. The aim of this paper is to perform, for the first time, a quantitative
analysis of the effects of IUGR in cardiac geometry and coronary vessel size in a wellknown rabbit model of IUGR using synchrotron-based X-ray Phase Contrast Tomography
Imaging (X-PCI). Eight rabbit fetal hearts were imaged non-destructively with X-PCI. 3D
reconstructions of the coronary arterial tree were obtained after semi-automatic image segmentation. Different morphometric features including vessel lumen diameter of the three
main coronaries were automatically quantified. IUGR fetuses had more globular hearts and
dilated coronary arteries as compared to controls. We have quantitatively shown that IUGR
leads to structural coronary vascular tree remodelling and enlargement as an adaptation
mechanism in response to an adverse environment of restricted oxygen and nutrients and
increased perfusion pressure
Mesurament de la concentració de massa de meropenem en el plasma mitjançant cromatografia lÃquida d'alta i rà pida eficà cia acoblada a l'espectrometria de masses en tà ndem
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