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The ultimate purpose of the statistical analysis of ordinal patterns is to characterize the distribution of the features they induce. In particular, knowing the joint distribution of the pair entropy-statistical complexity for a large class of time series models would allow statistical tests that are unavailable to date. Working in this direction, we characterize the asymptotic distribution of the empirical Shannon's entropy for any model under which the true normalized entropy is neither zero nor one. We obtain the asymptotic distribution from the central limit theorem (assuming large time series), the multivariate delta method, and a third-order correction of its mean value. We discuss the applicability of other results (exact, first-, and second-order corrections) regarding their accuracy and numerical stability. Within a general framework for building test statistics about Shannon's entropy, we present a bilateral test that verifies if there is enough evidence to reject the hypothesis that two signals produce ordinal patterns with the same Shannon's entropy. We applied this bilateral test to the daily maximum temperature time series from three cities (Dublin, Edinburgh, and Miami) and obtained sensible results.

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Post-surgical chylous ascites (CA) is extremely rare in colon surgery, known as the extravasation of creamy fluid rich in triglycerides accumulating in the peritoneal cavity. The incidence of CA after colorectal surgery remains between 1 and 6.5%. A 71-year-old female presented to the Emergency Department complaining of generalized abdominal pain, weakness and anorexia for several days ago and episodes of hematochezia which started the day before admission. Biopsy from colonoscopy revealed mucinous adenocarcinoma. Rectal mass resection with Hartmann's procedure was performed due to obstructive recto-colonic mass. Pathology report confirmed pT4aN0M0 tumor invading through the visceral peritoneum. On post-operative Day number 4, drainage output increased, changing appearance to a whitish color. The diagnosis of CA was confirmed by obtaining >550 mg per dL of triglycerides. Changes to a high-protein, low-fat with medium chain fatty acids were made to her enteral diet. After 48 hours of diet adjustment, the drainage output of CA resolved.

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BACKGROUND: Mexico has learned much from its five decades educating nurses, moving from nurses educated mostly at the technical degree level, to bachelor's degree prepared nurses educated in universities. Several salient lessons have emerged that may prove relevant for other countries seeking to increase their numbers of bachelors prepared nurses. This paper analyzes twenty years of nursing labor market data to highlight where significant social and policy changes helped facilitate increased production of bachelor's degree educated nurses in Mexico. METHODS: We conducted a two-stages analysis, starting with a descriptive stage and followed by a repeated cross-sectional analysis using data sources generated by the Secretariat of Health and the National Institute of Geography and Statistics. Data from the 2005 to 2019 period were analyzed for trends in production patterns and significant relationships in the labor market. RESULTS: Among Mexican nursing graduates, technical and bachelor nurses compete for employment in healthcare institutions. The public sector has greater success in hiring bachelors prepared nurses, but this varies by type of public sector institution. Technical degree nurses have higher underemployment rates and less job security overall. Private hospitals mainly hire technical degree nurses. The Mexican government not been able to properly regulate neither the production of new graduates nor the accreditation of schools, let alone to align roles according to the graduate's level of education. CONCLUSIONS: The success of Mexico in the twenty-first century shows that middle-income countries can increase the production and both private and public sector employment opportunities for nurses educated at both the technical and bachelor's degree level however, labor market challenges persist. The central lesson for other countries is that policies must be revised in order to optimize the use of a more educated nursing workforce.

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Although mitochondrial DNA has been widely used in phylogeography, evidence has emerged that factors such as climate, food availability, and environmental pressures that produce high levels of stress can exert a strong influence on mitochondrial genomes, to the point of promoting the persistence of certain genotypes in order to compensate for the metabolic requirements of the local environment. As recently discovered, the gentoo penguins (Pygoscelis papua) comprise four highly divergent lineages across their distribution spanning the Antarctic and sub-Antarctic regions. Gentoo penguins therefore represent a suitable animal model to study adaptive processes across divergent environments. Based on 62 mitogenomes that we obtained from nine locations spanning all four gentoo penguin lineages, we demonstrated lineage-specific nucleotide substitutions for various genes, but only lineage-specific amino acid replacements for the ND1 and ND5 protein-coding genes. Purifying selection (dN/dS < 1) is the main driving force in the protein-coding genes that shape the diversity of mitogenomes in gentoo penguins. Positive selection (dN/dS > 1) was mostly present in codons of the Complex I (NADH genes), supported by two different codon-based methods at the ND1 and ND4 in the most divergent lineages, the eastern gentoo penguin from Crozet and Marion Islands and the southern gentoo penguin from Antarctica respectively. Additionally, ND5 and ATP6 were under selection in the branches of the phylogeny involving all gentoo penguins except the eastern lineage. Our study suggests that local adaptation of gentoo penguins has emerged as a response to environmental variability promoting the fixation of mitochondrial haplotypes in a non-random manner. Mitogenome adaptation is thus likely to have been associated with gentoo penguin diversification across the Southern Ocean and to have promoted their survival in extreme environments such as Antarctica. Such selective processes on the mitochondrial genome may also be responsible for the discordance detected between nuclear- and mitochondrial-based phylogenies of gentoo penguin lineages.

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The aim of this study is to formulate a new methodology based upon informational tools to detect patients with cardiac arrhythmias. As it is known, sudden death is the consequence of a final arrhythmia, and here lies the relevance of the efforts aimed at the early detection of arrhythmias. The information content in the time series from an electrocardiogram (ECG) signal is conveyed in the form of a probability distribution function, to compute the permutation entropy proposed by Bandt and Pompe. This selection was made seeking its remarkable conceptual simplicity, computational speed, and robustness to noise. In this work, two well-known databases were used, one containing normal sinus rhythms and another one containing arrhythmias, both from the MIT medical databank. For different values of embedding time delay τ, normalized permutation entropy and statistical complexity measure are computed to finally represent them on the horizontal and vertical axes, respectively, which define the causal plane H×C. To improve the results obtained in previous works, a feature set composed by these two magnitudes is built to train the following supervised machine learning algorithms: random forest (RF), support vector machine (SVM), and k nearest neighbors (kNN). To evaluate the performance of each classification technique, a 10-fold cross-validation scheme repeated 10 times was implemented. Finally, to select the best model, three quality parameters were computed, namely, accuracy, the area under the receiver operative characteristic (ROC) curve (AUC), and the F1-score. The results obtained show that the best classification model to detect the ECG coming from arrhythmic patients is RF. The values of the quality parameters were at the same levels reported in the available literature using a larger data set, thus supporting this proposal that uses a very small-sized feature space to train the model later used to classify. Summarizing, the attained results show the possibility to discriminate both groups of patients, with normal sinus rhythm or arrhythmic ECG, showing a promising efficiency in the definition of new markers for the detection of cardiovascular pathologies.

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Dipole-dipole interactions lead to frequency shifts that are expected to limit the performance of next-generation atomic clocks. In this work, we compute dipolar frequency shifts accounting for the intrinsic atomic multilevel structure in standard Ramsey spectroscopy. When interrogating the transitions featuring the smallest Clebsch-Gordan coefficients, we find that a simplified two-level treatment becomes inappropriate, even in the presence of large Zeeman shifts. For these cases, we show a net suppression of dipolar frequency shifts and the emergence of dominant nonclassical effects for experimentally relevant parameters. Our findings are pertinent to current generations of optical lattice and optical tweezer clocks, opening a way to further increase their current accuracy, and thus their potential to probe fundamental and many-body physics.

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INTRODUCTION AND AIMS: Double-balloon enteroscopy is a recently introduced endoscopic method that enables complete visualization of the small bowel, as well as biopsy sampling and therapeutic interventions in that part of the intestine. The aim of the present study was to describe the experience acquired at our hospital to determine the characteristics of the patients that underwent the procedure. MATERIALS AND METHODS: A descriptive, cross-sectional study was conducted on all patients above 18 years of age admitted to the Hospital Universitario de la Fundación Santa Fe de Bogotá for double-balloon enteroscopy, within the time frame of January 2013 to December 2017. RESULTS: The study sample included 93 procedures in 73 patients. Mean patient age was 57.91 years, with a similar number of men and women. There were no severe complications. The most frequent indication for the enteroscopy was gastrointestinal bleeding (overt or occult), presenting in 49.46% of the patients, followed by chronic diarrhea (16.13%). Video capsule endoscopy was the previous study most frequently performed (53.76%). Anterograde double-balloon enteroscopy was carried out in 49 patients and 44 patients underwent the retrograde procedure. A total of 86.02% of the enteroscopies were diagnostic procedures and 13.98% were therapeutic. Normal enteroscopy was the most frequent finding (59.68%), followed by the presence of ulcers (15.05%). CONCLUSIONS: Our results were similar to those reported worldwide, with respect to indications, insertion route, and insertion depth, and there were no severe complications.

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Since at least the middle-Miocene, the Antarctic Polar Front (APF) and the Subtropical Front (STF) appear to have been the main drivers of diversification of marine biota in the Southern Ocean. However, highly migratory marine birds and mammals challenge this paradigm and the importance of oceanographic barriers. Eudyptes penguins range from the Antarctic Peninsula to subantarctic islands and some of the southernmost subtropical islands. Because of recent diversification, the number of species remains uncertain. Here we analyze two mtDNA (HVRI, COI) and two nuclear (ODC, AK1) markers from 13 locations of five putative Eudyptes species: rockhopper (E. filholi, E. chrysocome, and E. moseleyi), macaroni (E. chrysolophus) and royal penguins (E. schlegeli). Our results show a strong phylogeographic structure among rockhopper penguins from South America, subantarctic and subtropical islands supporting the recognition of three separated species of rockhopper penguins. Although genetic divergence was neither observed among macaroni penguins from the Antarctic Peninsula and sub-Antarctic islands nor between macaroni and royal penguins, population genetic analyses revealed population genetic structure in both cases. We suggest that the APF and STF can act as barriers for these species. While the geographic distance between colonies might play a role, their impact/incidence on gene flow may vary between species and colonies.

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Objetivos: Cuantificar donantes, personas que aceptan tratamientos invasivos, que firmarían órdenes de no reanimar, que avalarían transfusiones a personas contra su voluntad, que aceptan el aborto, la eutanasia y la investigación experimental, en todos los casos vinculando la respuesta con fundamentaciones. Materiales y Métodos: Diseño prospectivo, de observación, longitudinal, analítico. En 2007-2008, se estudiaron 848 adolescentes de 13 escuelas públicas de enseñanza media del área de responsabilidad de un hospital del Gobierno de la Ciudad Autónoma de Buenos Aires, en quienes se aplicó una encuesta autoadministrada abierta-cerrada. Se interrogó sobre situaciones vinculadas a aspectos bioéticos. Resultados: Los donantes representan el 75% de la muestra, el 46% desea que le implementen todo tratamiento posible, el 30% firmaría una orden de no reanimación, el 32% avala las transfusiones a Testigos de Jehová, el 57% acepta el aborto; el 81%, la eutanasia; el 62%, la investigación experimental. No hay diferencias de aceptación del aborto y la eutanasia entre católicos y no creyentes (p 0,10 y 0,30, respectivamente). En el análisis multivariado, la implementación de todo tipo de tratamiento se vinculó a no firmar una orden de no reanimar (p 0,0000) y a no respetar la voluntad de los Testigos de Jehová (p 0,0024). La aceptación de la eutanasia se vincula con la aceptación de aborto (p 0,0000) y firmar una orden de no reanimar (p 0,0266). Conclusiones: Los valores más votados fueron la veracidad y la justicia. La escuela media es un sitio de alto impacto para educar en bioética y derechos de ciudadanía(AU)

Objectives: To quantify donors, people who would accept invasive treatments, who would sign orders not to resuscitate, who would support transfusions to persons against their will, who would accept abortion, euthanasia, and experimental research, in all cases supporting their choices with foundations. Materials and Methods: Prospective, observational, longitudinal and analytical study. During 2007-2008, 848 teenagers belonging to 13 public high schools in the area of responsibility of a hospital from Gobierno de la Ciudad Autónoma de Buenos Aires were studied. They were given a self-administered opened-closed survey which included questions about situations linked to bioethical aspects. Results: Donors represent 75% of the sample, 46% wish to get any possible treatment, 30% would sign a do-not-resuscitate order, 32% support transfusions to Jehovah's Witnesses, 57% accept abortion, 81% euthanasia, 62% experimental research. There are no differences on acceptance of abortion and euthanasia between Catholics and non-believers (p 0.10 and 0.30, respectively). In the multivariate analysis, the implementation of all kinds of treatment was linked to a refusal to sign a do-not-resuscitate order (p 0.0000) and to not respecting the will of the Jehovah's Witnesses (p 0.0024). The acceptance of euthanasia links itself, in the analysis multivariate, to accepting abortion (p 0.0000) and to signing a do-not-resuscitate order (p 0.0266). Conclusions: The majority vote in favor of veracity and justice. High school is a high impact point to educate on bioethics and rights of citizenship(AU)

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