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This work analyzes the magnetic configurations of cylindrical nanowires with a bulk Dzyaloshinskii-Moriya interaction and easy-plane anisotropy. We show that this system allows the nucleation of a metastable toron chain even when no out-of-plane anisotropy exists in the nanowire's top and bottom surfaces, as usually required. The number of nucleated torons depends on the nanowire length and the strength of an external magnetic field applied to the system. The size of each toron depends on the fundamental magnetic interactions and can be controlled by external stimuli, allowing the use of these magnetic textures as information carriers or nano-oscillator elements. Our results evidence that the topology and structure of the torons yield a wide variety of behaviors, revealing the complex nature of these topological textures, which should present an exciting interaction dynamic, depending on the initial conditions.

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Using numerical simulations, we studied the dynamics of two skyrmions nucleated in a double-disk structure. Depending on the geometry and the electric current, different regimes for the dynamical behavior of the skyrmions were obtained. Our results evidence that there are four main dynamic regimes depending on the geometry and current: stagnation points, oscillatory motion, and two types of skyrmion annihilation: partial and total. Our findings are explained as a result of the different forces that skyrmions are subject to and are shown in a state diagram of the dynamical states that allow an adequate understanding of the associate phenomena.

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In this work, we present an analysis of skyrmion dynamics considering Dzyaloshinskii-Moriya interactions in an STNO device with a double-disk geometry. Three regimes were observed as a function of geometric parameters and the electric current density: (i) the skyrmion is annihilating at the system's border; (ii) the skyrmion moves in a non-circular trajectory alternating its position between the two disks, and (iii) the skyrmion only rotates inside a one-disk subsystem. For the annihilation state, we found that the transient time decays within a stretched exponential law as a function of the electric current. Our results show a 2D state diagram that can guide new experimental work in order to obtain these specific behaviors for new applications based on skyrmion dynamics.

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Severe respiratory alkalosis is a life-threatening condition, as it induces hypo- calcaemia and extreme adrenergic sensitivity leading to cerebral and myocardial vasoconstriction. We report a 37-year-old woman with previous consultations for a conversion disorder. While she was infected with SARS-CoV-2 (without pulmonary involvement), she consulted in the emergency room due to panic attacks. On admission, she developed a new conversion crisis with progressive clinical deterioration, hyperventilation, and severe respiratory alkalosis (pH 7.68, Bicarbonate 11.8 mEq/L and PaCO2 10 mmHg). Clinically, she was in a coma, with respiratory and heart rates 55 and 180 per min, a blood pressure of 140/90 mmHg, impaired perfusion (generalized lividity, distal coldness, and severe skin mottling) and tetany. She also had electrocardiographic changes and high troponin levels suggestive of ischemia, and hyperlactatemia. She was managed in the hospital with intravenous benzodiazepines. The clinical and laboratory manifestations resolved quickly, without the need for invasive measures and without systemic repercussions.

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Severe respiratory alkalosis is a life-threatening condition, as it induces hypo- calcaemia and extreme adrenergic sensitivity leading to cerebral and myocardial vasoconstriction. We report a 37-year-old woman with previous consultations for a conversion disorder. While she was infected with SARS-CoV-2 (without pulmonary involvement), she consulted in the emergency room due to panic attacks. On admission, she developed a new conversion crisis with progressive clinical deterioration, hyperventilation, and severe respiratory alkalosis (pH 7.68, Bicarbonate 11.8 mEq/L and PaCO2 10 mmHg). Clinically, she was in a coma, with respiratory and heart rates 55 and 180 per min, a blood pressure of 140/90 mmHg, impaired perfusion (generalized lividity, distal coldness, and severe skin mottling) and tetany. She also had electrocardiographic changes and high troponin levels suggestive of ischemia, and hyperlactatemia. She was managed in the hospital with intravenous benzodiazepines. The clinical and laboratory manifestations resolved quickly, without the need for invasive measures and without systemic repercussions.

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Quillaja genus (Quillajaceae family) is endemic to South America, where is represented by two species, Quillaja saponaria and Quillaja brasiliensis. One outstanding characteristic of these forest tree species is their production of saponins, a family of amphipathic glycosides, involved in the defensive response of plants against biotic and abiotic factors. Saponins are metabolites of economic importance due to their chemical and physical properties. Basic and applied research efforts performed during the last decades, mainly on Q. saponaria, have placed these compounds as an important raw material in industrial areas, such as food and beverage, cosmetics, vaccine production, biopesticides, among others. In this review, we summarize information on saponins from Quillaja species during the last years, analyzing current developments by application areas, as well as their chemical composition and properties. We also describe the general advances in revealing saponin biosynthesis pathways, related genes and Quillaja genomes, as well as the conservation status, domestication processes, and perspectives in the context of implementing genetic improvement programs.

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Quillaja genus (Quillajaceae family) is endemic to South America, where is represented by two species, Quillaja saponaria and Quillaja brasiliensis. One outstanding characteristic of these forest tree species is their production of saponins, a family of amphipathic glycosides, involved in the defensive response of plants against biotic and abiotic factors. Saponins are metabolites of economic importance due to their chemical and physical properties. Basic and applied research efforts performed during the last decades, mainly on Q. saponaria, have placed these compounds as an important raw material in industrial areas, such as food and beverage, cosmetics, vaccine production, biopesticides, among others. In this review, we summarize information on saponins from Quillaja species during the last years, analyzing current developments by application areas, as well as their chemical composition and properties. We also describe the general advances in revealing saponin biosynthesis pathways, related genes and Quillaja genomes, as well as the conservation status, domestication processes, and perspectives in the context of implementing genetic improvement programs.(AU)

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La Telemedicina constituye una herramienta que permite proporcionar atención médica especializada usando la tecnología de las telecomunicaciones.Entre mayo del 2015 y julio del 2017 se realizaron 1020 atenciones a través de esta modalidad, entre el Hospital Puerto Montt (HPM) y distintos centros de Atención primaria del SS Reloncaví.Se utilizaron dos modalidades de atención: asincrónica y sincrónica con presencia virtual del paciente.Se realizaron 1020 atenciones con una resolución inmediata en el 61,7% de los casos. Esta modalidad de atención implicó un ahorro de 139.412 Km, y por concepto de pasajes de $ 10.675.200 requeridos para el desplazamiento de los pacientes desde su lugar de origen al HPM.En lugares geográficamente distantes, la Telereumatología se convierte en una herramienta fundamental que permite expandir la cobertura de atenciones de salud por especialista, reducir las listas de espera, disminuir los tiempos de traslado y el costo que estos implican.

Telemedicine constitutes a tool that allows to provide specialized medical attention using telecommunications technology.Between May 2015 and July 2017, 1,020 care were carried out through this modality, between the Puerto Montt Hospital (HPM) and different primary care centers of the SS Reloncavi.Two care modalities were used: asynchronous and synchronous with the virtual presence of the patient.1020 visits were performed with immediate resolution in 61.7% of the cases.This care modality implied a saving of 139,412 km, and for the concept of passages of $ 10,675,200 required for the movement of patients from their place of origin to the HPM.In geographically remote places, Telerheumatology becomes a fundamental tool that allows expanding the coverage of health care by specialist, reducing waiting lists, reducing travel times and the cost that these imply.

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It is still controversial if the combined use of beta-lactam antibiotics and aminoglycosides has advantages over broad-spectrum beta-lactam monotherapy for the empirical treatment of cancer patients with febrile neutropenia. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified three systematic reviews including 14 pertinent randomized trials. We combined the evidence using meta-analysis and generated a summary of findings table following the GRADE approach. We concluded the combination of beta-lactam antibiotics and aminoglycosides probably does not lead to a reduced mortality in febrile neutropenic cancer patients and it might increase nephrotoxicity.

En pacientes con cáncer que se presentan con neutropenia febril existe controversia sobre si es mejor utilizar una combinación de antibióticos betalactámicos y aminoglicósidos o si bastaría la monoterapia con betalactámicos de amplio espectro como tratamiento empírico inicial. Utilizando la base de datos Epistemonikos, la cual es mantenida mediante búsquedas en 30 bases de datos, identificamos tres revisiones sistemáticas que en conjunto incluyen 14 estudios aleatorizados pertinentes a esta pregunta. Realizamos un metanálisis y tablas de resumen de los resultados utilizando el método GRADE. Concluimos que adicionar aminoglicósidos a los betalactámicos en el tratamiento de la neutropenia febril en pacientes con cáncer aumenta la nefrotoxicidad y podría aumentar la mortalidad en comparación con la monoterapia con betalactámicos.

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PURPOSE: To establish the construct validity of a semirigid ureteroscopy in a high-fidelity simulation model, incorporating hand motion analysis as a paramount part of evaluation. METHODS: Participants were divided into 3 groups: group 1 (9 junior residents, without experience in ureteroscopy), group II (9 senior residents, with variable experience in ureteroscopy) and group III (2 experts in endourologist); each group performed a single practice session in the high-fidelity bench model, which was previously prepared with small urinary stone phantom in the mid-ureter. Assessment was done using motion tracking device (ICSAD). Procedures were recorded in external vision and endoscopic vision and scored by two blinded evaluators using a Global Rating Scale and ureteral checklist (OSATS). RESULTS: Significant differences were observed in time taken, path length, numbers of movements, Global Rating Scale and checklist in favor of the experts group. Subanalysis demonstrated no relevant differences between groups II and III in general dexterity parameters except for the non-dominant hand, where experts showed a significant less number of movement (34 vs 221; p = 0.03) and path length (12.1 vs 45.1; p = 0.03). The interrater reliability of the GRS was excellent (0.81; p < 0.001), while for checklist ICC was moderate (0.45; p = 0.03). CONCLUSIONS: The incorporation of ICSAD into the construct validity of this ureteroscopy model complements traditional methods used to achieve construct validity (OSATS). To our knowledge, this study is the first report using motion analysis as a tool for performance evaluation in a simulated endourological procedure.

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Se analizan los aspectos clínicos de un conjunto de 86 pacientes portadoras de embarazos tubarios, reunidas en el Servicio de Obstetricia y Ginecología del Hospital Félix Bulnes durante los años 1981. 1982 y 1 er semestre de 1983. Entre los principales hechos detectados merecen destacarse los siguientes: 1. El 6% de los pacientes que conforman nuestra casuística tenían antecedentes de embarazos ectópicos, porcentaje que es inferior a los habitualmente comunicados en la literatura. 2. La clínica (amenorrea, sangramiento vaginal, dolor hipogástrico, hipotensión, abombamiento doloroso del fondo de saco de Douglas, etc) es la base del diagnóstico. 3. En la confirmación del diagnóstico clínico son importantes la punción del fondo de saco de Douglas, la ecografía y la laparoscopia. En el momento del diagnóstico, los dos tercios de los casos (68,6%) ya estaban complicados. 5. La localización más frecuente del embarazo tubario es la ampular, seguida de la ístmica y de la intersticial. 6. En el 87,2% de los casos el tratamiento quirúrgico consistió en salpingectomía unilateral con o sin ooforectomía. Sólo en el 12,8% se recurrió a la salpingectomía bilateral. 7. En el 86% el diagnóstico de ingreso fue correcto. Hay que señalar, no obstante, que en el 14% restante fue errado, lo que, sin lugar a duda, retardó el tratamiento quirúrgico

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El presente estudio de tipo exploratorio se realizó en una muestra de 86 mujeres con embarazo tubario y 100 puérperas sin este antecedente. Los hallazgos significativos entre los casos de embarazo tubario fueron: Mayor frecuencia de mujeres entre 31 y 40 años; Mayor frecuencia de cirugía abdominal previa; Mayor frecuencia de abortos previos; Mayor frecuencia de uso de dispositivos intrauterinos

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