Repeated 15-minute coronary occulsions in pigs increase occlusion arrhythmias but decrease reperfusion arrhythmias that are associated with extracellular hypokalemia

AbstractObjectives. We sought to evaluate the effects of repetitive 15-min coronary occlusions followed by 45-min reperfusions on the incidence of occlusion and reperfusion arrhythmias in pigs.Background. Brief 2- to 5-min coronary occlussions seem to exert a protective effect on occlusion and reperfusion arrhythmias. However, because clinical ischemic episodes are often longer, it would be appropriate to assess whether such protection also occurs when longer cycles of occlusion-reperfusion are produced.Methods. Three to four cycles of 15-min coronary occlusions with 45-min reperfusions were performed in 34 pigs, and changes in ST segment and incidence of ventricular arrhythmias were assessed. Plasma potassium ion concentrations in eight pigs and blood gas in six were measured from blood from the ischemic area during reperfusion.Results. Repetitive occlusions were associated with a progressively higher ST segment elevation and a higher incidence of ST segment alternans (p < 0.001) and ventricular fibrillation (VF) (p < 0.01). However, during repetitive reperfusions, normalization of the ST segment was increasingly faster, the incidence of VF was progressively reduced (p < 0.03), and there was progressively less severe regional acidosis ([mean ± SD] 7.06 ± 0.12 vs 7.26 ± 0.06, p < 0.05) and hypokalemia (1.9 ± 0.7 vs. 2.3 ± 0.4 mEq/liter, p = NS).Conclusions. The progressive electrocardiographic deterioration and increasing incidence of ventricular arrhythmias during repetitive 15-min occlusions in pigs suggest increasing metabolic derangement. However, the progressively faster normalization of the ST segment and the reduced incidence of ventricular arrhythmias during reperfusion suggest an increasingly faster restoration of the metabolic and ionic balance

Transferencia de resultados de investigación sobre enseñanza y aprendizaje de la geometría al aula

En este trabajo presentamos algunos ítems del test que hemos diseñado con objeto de obtener información sobre la Geometría que se enseña en escuelas de primaria de algunos estados de México y así poder, por un lado, valorar si la Geometría que se contempla en el currículum de primaria mexicano se corresponde con la que imparten estos maestros y, por otor, determinar las posibles causas que han llevado a la enseñanza de la geometría a la situación actual. En este informe hacemos también referencia a un estudio que estamos realizando en el que analizamos algunos libros de texto de primaria mexicanos y algunos de los test utilizados en este país para la evaluación de los estudiantes de este nivel

The causal factors of international inequality in co2 emissions per capita: a regression-based inequality decomposition analysis [WP]

This paper uses the possibilities provided by the regression-based inequality decomposition (Fields, 2003) to explore the contribution of different explanatory factors to international inequality in CO2 emissions per capita. In contrast to previous emissions inequality decompositions, which were based on identity relationships (Duro and Padilla, 2006), this methodology does not impose any a priori specific relationship. Thus, it allows an assessment of the contribution to inequality of different relevant variables. In short, the paper appraises the relative contributions of affluence, sectoral composition, demographic factors and climate. The analysis is applied to selected years of the period 1993–2007. The results show the important (though decreasing) share of the contribution of demographic factors, as well as a significant contribution of affluence and sectoral composition

Sparse image approximation with application to flexible image coding

Natural images are often modeled through piecewise-smooth regions. Region edges, which correspond to the contours of the objects, become, in this model, the main information of the signal. Contours have the property of being smooth functions along the direction of the edge, and irregularities on the perpendicular direction. Modeling edges with the minimum possible number of terms is of key importance for numerous applications, such as image coding, segmentation or denoising. Standard separable basis fail to provide sparse enough representation of contours, due to the fact that this kind of basis do not see the regularity of edges. In order to be able to detect this regularity, a new method based on (possibly redundant) sets of basis functions able to capture the geometry of images is needed. This thesis presents, in a first stage, a study about the features that basis functions should have in order to provide sparse representations of a piecewise-smooth image. This study emphasizes the need for edge-adapted basis functions, capable to accurately capture local orientation and anisotropic scaling of image structures. The need of different anisotropy degrees and orientations in the basis function set leads to the use of redundant dictionaries. However, redundant dictionaries have the inconvenience of giving no unique sparse image decompositions, and from all the possible decompositions of a signal in a redundant dictionary, just the sparsest is needed. There are several algorithms that allow to find sparse decompositions over redundant dictionaries, but most of these algorithms do not always guarantee that the optimal approximation has been recovered. To cope with this problem, a mathematical study about the properties of sparse approximations is performed. From this, a test to check whether a given sparse approximation is the sparsest is provided. The second part of this thesis presents a novel image approximation scheme, based on the use of a redundant dictionary. This scheme allows to have a good approximation of an image with a number of terms much smaller than the dimension of the signal. This novel approximation scheme is based on a dictionary formed by a combination of anisotropically refined and rotated wavelet-like mother functions and Gaussians. An efficient Full Search Matching Pursuit algorithm to perform the image decomposition in such a dictionary is designed. Finally, a geometric image coding scheme based on the image approximated over the anisotropic and rotated dictionary of basis functions is designed. The coding performances of this dictionary are studied. Coefficient quantization appears to be of crucial importance in the design of a Matching Pursuit based coding scheme. Thus, a quantization scheme for the MP coefficients has been designed, based on the theoretical energy upper bound of the MP algorithm and the empirical observations of the coefficient distribution and evolution. Thanks to this quantization, our image coder provides low to medium bit-rate image approximations, while it allows for on the fly resolution switching and several other affine image transformations to be performed directly in the transformed domain

Breaking the silence on special needs children in foster care: The diversity of children in foster care, carers and processes

This study aims to advance the understanding of children with special needs in foster care by identifying the characteristics, processes, and outcomes of their placement. The study uses a quantitative approach to identify 190 children with special needs (registered) from among 2,157 foster children in Catalonia and the Balearic Islands, Spain and examines key data covering 2008 to 2018. The results show that children with special needs are overrepresented in placements with single-parent foster carers (mainly women), raising questions about the extent to which the care system takes the complexity of special needs into account

8T SRAM Cell with Open Defects under Voltage and Timing Variations

Postprint (published version

Mucocutaneous Response to New Therapeutic Strategies in Behçet’s Disease: A Retrospective Cohort Study

Mucocutaneous lesions are the most frequent symptoms of Behcet's disease (BD). Recently, new therapies are being used to treat refractory cases, but the effect of these treatments on mucocutaneous manifestations has been scarcely reported. Our objective was to describe the mucocutaneous response to the different therapies used to treat BD in routine clinical practice. We retrospectively reviewed the clinical records of all patients diagnosed with BD seen at our institution between January 2010 and January 2022. Patients with BD without mucocutaneous manifestations were excluded. We included 109 patients diagnosed with BD: 51 males (46.8%) and 58 females (53.2%). The mean age at diagnosis was 31.58 years (standard deviation (SD) 12.110) and the mean time of disease evolution was 14.94 years (SD 11.094). Oral ulcers were the most frequent symptom present in 100% of patients, followed by genital ulcers (GU) in 76.1% of patients. Twenty-four patients (22%) had severe mucocutaneous symptoms (> 12 lesions/year) before treatment. We found that among patients with GU there was a higher prevalence of episodes of posterior uveitis and venous thrombosis (p=0.011 and p=0.045, respectively). In our series, we observed a lower complete cutaneous response to colchicine in patients with GU, pathergy or severe mucocutaneous symptoms (p < 0.05). Regarding the choice of a TNF-alpha inhibitor, we observed a lower prevalence of complete cutaneous response to adalimumab among patients with GU (53.3% complete response in patients with GU vs. 100% in patients without GU, p=0.022), whereas no differences were found between clinical characteristics in the response to infliximab

Impact of gate tunnelling leakage on CMOS circuits with full open defects

Electronics Letter of the MonthInterconnecting lines with full open defects become floating lines. In nanometric CMOS technologies, gate tunnelling leakage currents impact the behaviour of these lines, which cannot be considered electrically isolated anymore. The voltage of the floating node is determined by its neighbours and leakage currents. After some time an equilibrium is reached between these effects. Theoretical analysis and experimental evidence of this behaviour are presented.Peer ReviewedAward-winningPostprint (published version