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During the past decades magnetic materials and structures that span several length scales have been of interest mainly due to their application in data storage and processing, flexible electronics, medicine, between others. From a microscopic point of view, these systems are typically studied using the Landau-Lifshitz equation (LLE), while approaches such as the dumbbell model are used to study macroscopic magnetic structures. In this work we use both the LLE and the dumbbell model to study spin chains of various lengths under the effect of a time dependent-magnetic field, allowing us to compare qualitatively the results obtained by both approaches. This has allowed us to identify and describe in detail several frequency modes that appear, with additional modes arising as the chain length increases. Moreover, we find that high frequency modes tend to be absorbed by lower frequency ones as the amplitude of the field increases. The results obtained in this work are of interest not only to better understand the behavior of the macroscopic spins chains, but also expands the available tools for qualitative studies of both macroscopic and microscopic versions of the studied system, or more complex structures such as junctions or lattices. This would allow to study the qualitative behavior of microscopic systems (e.g. nanoparticles) using macroscopic arrays of magnets, and vice versa.

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Purpose: The main purpose of this study was to report a case of cystoid macular edema (CME) after gonioscopy-assisted transluminal trabeculotomy (GATT). Methods: We describe the case of a 73-year-old woman with ocular hypertension and history of cataract surgery combined with posterior vitrectomy and epiretinal membrane peeling 2 years before, who developed CME after uncomplicated GATT procedure. Results: Uneventful GATT surgery was performed in an eye with ocular hypertension. A month after GATT surgery, the patient com-plained of blurry vision. Best corrected visual acuity had deteriorated from 20/20 on Snellen chart, to 20/70. The patient was diagnosed with CME. Treatment with topical non-steroidal anti-inflammatory drug (NSAID) and topical corticosteroids for one month, and oral carbonic anhydrase inhibitor for one week achieved a total CME regression with recovery of a normal macular and foveal architecture. Conclusions: Surgery-induced CME may occur following stand-alone microinvasive glaucoma surgery (MIGS) such as GATT. It would be worthwhile to conduct studies to explore whether the prophylactic use of NSAID and corticosteroids is justified.

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Full-thickness macular hole is a rare complication of macular telangiectasia type 2, and its treatment is still controversial. A patient with a full-thickness macular hole secondary to macular telangiectasia type 2 underwent vitreoretinal surgery with a plasma rich in growth factors membrane in the macular hole. At the sixth month of follow-up, anatomical and functional improvements were achieved, with no adverse effects. Plasma rich in growth factors is a new option, with advantages due to its biological properties that achieves good results in terms of safety and effectiveness in the surgical treatment of macular hole.

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Macroscopic magnets can easily be manipulated and positioned so that interactions between themselves and with external fields induce interesting dynamics and equilibrium configurations. In this work, we use rotating magnets positioned in a line or at the vertices of a regular polygon. The rotation planes of the magnets can be modified at will. The rich structure of stable and unstable configurations is dictated by symmetry and the side of the polygon. We show that both symmetric solutions and their symmetry-breaking bifurcations can be explained with group theory. Our results suggest that the predicted magnetic textures should emerge at any length scale as long as the interaction is polar, and the system is endowed with the same symmetries.

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Resumen Objetivo: Mostrar los resultados en el corto y mediano plazo del tratamiento endovascular de angioplastia transluminal percutánea (ATP) con balón en pacientes en estado de isquemia crítica por enfermedad arterial obstructiva infrapoplítea. Materiales y Método: Estudio descriptivo, observacional, retrospectivo. Se incluyeron los pacientes hospitalizados entre 2009 y 2018 por isquemia crítica Fontaine III o IV sometidos a una ATP del territorio infrapoplíteo. Se observó como objetivos primarios la preservación de la extremidad afectada y la mortalidad posoperatoria a un año plazo, y como objetivos secundarios los procedimientos adicionales en pacientes con lesiones o necrosis distales, estadía hospitalaria, complicaciones posoperatorias y necesidad de reintervención. Resultados: Se incluyeron 42 pacientes con un promedio de edad de 66 años (46-82), con importantes comorbilidades. Un 83,3% ingresó en etapa Fontaine IV. En 16 casos se realizó una angioplastia percutánea en más de una arteria. No se colocó stents. Se presentaron complicaciones en 3 pacientes, 2 requirieron una amputación mayor y en otro se debió efectuar un nuevo procedimiento endovascular de rescate. La estadía hospitalaria promedio fue 22 días. No hubo mortalidad precoz posprocedimiento. La mortalidad global a un año fue 9,5%. A todos los pacientes en etapa Fontaine IV se les efectuó algún procedimiento adicional, a 31 una amputación menor, 3 cerraron sus lesiones por segunda intención y en otro se realizó un injerto dermo-epidérmico. De los 35 pacientes con seguimiento, 77% preservó su extremidad a un año. Conclusión: La reparación endovascular mediante una angioplastia percutánea en estos casos es un procedimiento seguro y tiene una alta tasa de preservación de la extremidad inicial a un año de seguimiento.

Aim: Show initial and midterms results of endovascular Percutaneous Transluminal Angioplasty (PTA) in critical limb isquemia (CLI) patients caused by below-the-knee arterial disease. Materials and Method: Observational, descriptive and retrospective study. 42 CLI patients admitted in our hospital from 2009 until 2018 with Fontaine III or IV treated by PTA in infrapopliteal arteries were analyzed, collecting demographic, clinical and surgical characteristics, additional procedures in Fontaine IV, hospital stay, postoperative complications, need of reintervention, limb preservation and mortality with one year follow-up after procedure. Results: 42 patients, average age 66 year-old (46-82), with significant comorbidities. Fontaine IV stage patients were 83.3%. In 16 cases more than one artery was intervened. No stent revascularization was performed. Complications occurred in 3 patients, 2 required major amputation and an urgent endovascular reintervention was required in another. Average hospital stay was 22 days with no post-operative mortality. One-year global mortality was 9.5 One-year follow-up in 35 patients shows that 77% preserved their limb. Conclusión: Percutaneous transluminal angioplasty procedure in this patients has a high rate of limb preservation in a one-year follow-up. There was no post-operative mortality.

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Full-thickness macular hole is a rare complication of macular telangiectasia type 2, and its treatment is still controversial. A patient with a full-thickness macular hole secondary to macular telangiectasia type 2 underwent vitreoretinal surgery with a plasma rich in growth factors membrane in the macular hole. At the sixth month of follow-up, anatomical and functional improvements were achieved, with no adverse effects. Plasma rich in growth factors is a new option, with advantages due to its biological properties that achieves good results in terms of safety and effectiveness in the surgical treatment of macular hole.

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Cancer of unknown primary (CUP) is defined as a heterogeneous group of tumours that present with metastasis, and in which attempts to identify the original site have failed. They differ from other primary tumours in their biological features and how they spread, which means that they can be considered a separate entity. There are several hypotheses regarding their origin, but the most plausible explanation for their aggressiveness and chemoresistance seems to involve chromosomal instability. Depending on the type of study done, CUP can account for 2-9% of all cancer patients, mostly 60-75 years old. This article reviews the main clinical, pathological, and molecular studies conducted to analyse and determine the origin of CUP. The main strategies for patient management and treatment, by both clinicians and pathologists, are also addressed.

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Introducción: Más de la tercera parte de los homicidios reportados a nivel mundial tienen lugar en el continente Americano, siendo Chile uno de los países con las tasas más bajas de Latinoamérica. Actualmente, son escasos los estudios que caracterizan el acto homicida en nuestro país. Se caracterizó el acto homicida según las autopsias realizadas por el Servicio Médico Legal (SML) de Concepción, durante el periodo 2011-2015. Materiales y método: Se realizó un estudio transversal de informes de autopsia con causa homicidio durante los años 2011 a 2015, realizadas por el SML de Concepción, utilizándose las variables: género, edad, procedencia, lugar de ocurrencia del homicidio, estado civil, ocupación, patologías asociadas, causa de muerte, tipo de arma utilizada, alcoholemia, examen toxicológico y atención en centro asistencial. El estudio fue aprobado por comité de ética. Resultados: Del total de autopsias en el periodo 2011-2015; 5.92% (241) correspondieron a homicidios, de los cuales un 89.6% fueron víctimas de sexo masculino. Del total de homicidios estudiados la edad promedio fue de 33 años, un 58.3% del total ocurrieron en vía pública y 42.1% fallecieron por trauma torácico complicado. Finalmente del total de homicidios, un 49,2% poseían alcoholemia negativa y 49.2% examen toxicológico negativo. Discusión: En Chile, el homicidio afecta a una pequeña porción de la población, acercándose a las bajas tasas que presentan diversos países de Europa. En su mayoría, los homicidios reportados fueron hombres entre los 18 y 29 años de edad, resultado similar a lo descrito a nivel mundial.

Introduction: More than a third part of the worldwide reported homicides takes place in the whole american continent, and Chile is one the countries with the lowest rates in latin america. Only a few are the studies that characterize the homicidal act in our country. Characterize the homicide act according to the autopsies reports performed by the Legal Medical Service (SML) of Concepción, during the period 2011-2015. Materials and methods: We made a transversal study with the autopsies reports classified as homicide, performed by the SML Concepción, between the years 2011 and 2015 using variables such as: gender, age, place of residence, place of homicidal act, marital state, occupation, comorbidities, death cause, weapon, blood alcohol concentration, toxicological results and medical assistance. An ethic committee approved the study. Results: From the total autopsies between 2011 and 2015; 5.92% (241) were homicides, of which 89.4% were men. The average age of homicides victims was 33 years old, 58.3% occurred on public areas and 42.1% were died because a complicated thoracic traumatism. And finally from the total homicides, 49.2% had none alcohol in blood such as the 49.2% as well had negative toxicological test. Discussion: In Chile, homicide affects a few number of its population, approaching the low rates that some european countries have. The most of the homicides reported were men between 18 to 29 years old, similar results comparing with the worldwide statistics.

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This study was performed to determine the effects of gamma irradiation on UV spectrum on maca, total content of polyphenols, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities and in vivo biological activities of red and black maca extracts (Lepidium meyenii). Adult mice of the strain Swiss aged 3 months and weighing 30-35 g in average were used to determine biological activities. Daily sperm production, effect on testosterone-induced prostate hyperplasia and forced swimming test were used to determine the effect of irradiation on biological activities of maca extracts. Irradiation did not show differences in UV spectrum but improves the amount of total polyphenols in red maca as well as in black maca extracts. In both cases, black maca extract has more content of polyphenols than red maca extract (p < 0.01). Gamma irradiation significantly increased the antioxidant capacity (p < 0.05). No difference was observed in daily sperm production when irradiated and nonirradiated maca extract were administered to mice (p > 0.05). Black maca extract but not red maca extract has more swimming endurance capacity in the forced swimming test. Irradiation of black maca extract increased the swimming time to exhaustion (p < 0.05). This is not observed with red maca extract (p > 0.05). Testosterone enanthate (TE) increased significantly the ventral prostate weight. Administration of red maca extract in animals treated with TE prevented the increase in prostate weight. Irradiation did not modify effect of red maca extract on prostate weight (p > 0.05). In conclusion, irradiation does not alter the biological activities of both black maca and red maca extracts. It prevents the presence of microorganisms in the extracts of black or red maca, but the biological activities were maintained.

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In 2011, the Spanish Society of Medical Oncology and the Spanish Society of Pathology started a joint project to establish recommendations on biomarker testing in patients with advanced non-small-cell lung cancer based on the current evidence. Most of these recommendations are still valid, but new evidence requires some aspects to be updated. Specifically, the recommendation about which biomarkers to test in which patients is being amended, and the best way to manage tumour samples and minimum requirements for biomarker test material are defined. Suitable techniques for testing for epidermal growth factor receptor mutations and anaplastic lymphoma kinase rearrangement are also reviewed, and a consensus is reached on which situations warrant re-biopsy.

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