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Mexico is a major center of evolutionary radiation for the genus Quercus, with oak species occurring across different habitat types and showing a wide variation in morphology and growth form. Despite representing about 20% of Mexican species, scrub oaks have received little attention and even basic aspects of their taxonomy and geographic distribution remain unresolved. In this study, we analyzed the morphological and climatic niche differentiation of scrub oak populations forming a complex constituted by six named species, Quercus cordifolia, Quercus frutex, Quercus intricata, Quercus microphylla, Quercus repanda, Quercus striatula and a distinct morphotype of Q. striatula identified during field and herbarium work (hereafter named Q. striatula II). Samples were obtained from 35 sites covering the geographic distribution of the complex in northern and central Mexico. Morphological differentiation was analyzed through geometric morphometrics of leaf shape and quantification of trichome traits. Our results indicated the presence of two main morphological groups with geographic concordance. The first was formed by Q. frutex, Q. microphylla, Q. repanda and Q. striatula, distributed in the Trans-Mexican Volcanic Belt, the Sierra Madre Occidental and a little portion of the south of the Mexican Altiplano (MA). The second group consists of Q. cordifola, Q. intricata and Q. striatula II, found in the Sierra Madre Oriental and the MA. Therefore, our evidence supports the distinctness of the Q. striatula II morphotype, indicating the need for a taxonomic revision. Within the two groups, morphological differentiation among taxa varied from very clear to low or inexistent (i.e. Q. microphylla-Q. striatula and Q. cordifolia-Q. striatula II) but niche comparisons revealed significant niche differentiation in all pairwise comparisons, highlighting the relevance of integrative approaches for the taxonomic resolution of complicated groups such as the one studied here.

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PREMISE: Phylogeographical studies are fundamental for understanding factors that influence the spatial distribution of genetic lineages within species. Population expansions and contractions, distribution shifts, and climate changes are among the most important factors shaping the genetic compositions of populations. METHODS: We investigated the phylogeography of an endemic oak, Quercus mexicana (Fagaceae), which has a restricted distribution in northeastern Mexico along the Sierra Madre Oriental and adjacent areas. Nuclear and chloroplast DNA microsatellite markers were used to describe the genetic diversity and structure of 39 populations of Q. mexicana along its entire distribution area. We tested whether population expansion or contraction events influenced the genetic diversity and structure of the species. We also modeled the historical distributional range of Q. mexicana (for the Mid Holocene, the Last Glacial Maximum, and the Last Interglacial) to estimate the extent to which climate fluctuations have impacted the distribution of this oak species. RESULTS: Our results revealed high genetic diversity and low genetic structure in Q. mexicana populations. Ecological niche models suggested historical fluctuations in the distributional range of Q. mexicana. Historical range changes, gene flow, and physical barriers seem to have played an important role in shaping the phylogeographic structure of Q. mexicana. CONCLUSIONS: Our study indicates that the genetic structure of Q. mexicana may have been the result of responses of oak trees not only to heterogeneous environments present in the Sierra Madre Oriental and adjacent areas, but also to elevational and latitudinal shifts in response to climate changes in the past.

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La pandemia por el nuevo coronavirus COVID- 19 ha tenido impacto en la salud mental del personal médico y de enfermería en todo el mundo. Objetivo: identificar la frecuencia de síntomas depresivos, ansiosos e insomnio y los factores posiblemente relacionados con estos desenlaces en el personal sanitario de un hospital de Suramérica durante el primer pico de la pandemia. Materiales y métodos: se aplicaron las escalas PHQ-9 para depresión, GAD- 7 para ansiedad, ISI - 7 para insomnio en 876 trabajadores de la salud del Hospital Pablo Tobón Uribe en la ciudad de Medellín. Resultados: de los 876 participantes (29,2% médicos, 21.2% profesionales de enfermería y 49,5% auxiliares de enfermería), 357 (40.8%) presentaron síntomas depresivos, 300 (34.2%) síntomas ansiosos y 317 (36.2%) insomnio. Se observaron síntomas de depresión, ansiedad e insomnio, con mayor frecuencia en quienes no tenían las necesidades básicas satisfechas y en quienes se sentían estigmatizados por ser personal de salud. Además, la depresión se presentó con más frecuencia en mujeres, la ansiedad en menores de 44 años y el insomnio en personas separadas. Conclusiones: la frecuencia de problemas de salud mental en el personal de salud es considerable. Estos hallazgos demuestran la necesidad de atención en la salud mental de los profesionales médicos y de enfermería durante la pandemia por COVID-19 y la búsqueda de estrategias para mitigar el riesgo en esta población.

Background: pandemic due to novel coronavirus COVID-19 has impacted on the mental health of health care workers all around the world. Material and Methods: this is a cross sectional study in which questionnaires PHQ-9 for depression, GAD-7 for anxiety, ISI-7 for insomnia were virtually and self administered by 876 health care workers laboring in hospital Pablo Tobón Uribe in Medellin city. Results: from 876 participants (29.2% physicians, 21.2% nurses and 49.5% technical nurses), 357 (40.8%) developed depressive symptoms, 300 (34.2%) anxious symptoms and 317 (36.2%) insomnia. Symptoms of depression, anxiety and insomnia were more frequently found in those who did not have basic needs satisfied and in those who felt stigmatized due to being health personal. Besides, depressive symptoms were more frequent in women, anxious symptoms in people younger than 44 years old and insomnia in divorced people. Conclusions: the frequency of mental health problems in health care workers is significant, these findings bring to light the needs for mental health attention in nurses and doctors during COVID-19 pandemic and the research of strategies to mitigate the risk on this population. Feeling stigmatized and not having basic needs satisfied were associated with symptoms of anxiety, depression and insomnia.

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Plastic particle occurrence in the digestive tracts of fishes from a tropical estuarine system in the Gulf of California was investigated. A total of 1095 fish were analysed, representing 15 species. In total 1384 particles of plastic debris were recovered from the gastrointestinal tracts of 552 specimens belonging to 13 species, and all consisted of threads, the majority of which were small microplastics (0.23 to 1.89), followed by large microplastics (2.07 to 4.49), and few mesoplastics (5.4 to 19.86). Plastic particles were identified using ATR-FTIR spectroscopy. The mean frequency of occurrence of plastics in the gastrointestinal tracts of fishes from this system was 50.5%, which is higher than frequencies reported in similar systems in other areas. The polymers identified by ATR-FTIR were polyamide (51.2%), polyethylene (36.6%), polypropylene (7.3%), and polyacrylic (4.9%). These results show the first evidence of plastic contamination for estuarine biota in the Gulf of California.

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Postoperative pain might be different after intravenous vs. oral paracetamol. We systematically reviewed randomised controlled trials in patients >15 years that compared intravenous with oral paracetamol for postoperative pain. We identified 14 trials with 1695 participants. There was inconclusive evidence for an effect of route of paracetamol administration on postoperative pain at 0-2 h (734 participants), 2-6 h (766 participants), 6-24 h (1115 participants) and >24 h (248 participants), with differences in standardised mean (95%CI) pain scores for intravenous vs. oral of -0.17 (-0.45 to 0.10), -0.09 (-0.24 to 0.06), 0.06 (-0.12 to 0.23) and 0.03 (-0.22 to 0.28), respectively. Trial sequential analyses suggested that a total of 3948 participants would be needed to demonstrate a meaningful difference in pain or its absence at 0-2 h. There were no differences in secondary outcomes. Intravenous paracetamol is more expensive than oral paracetamol. Substitution of oral paracetamol in half the patients given intravenous paracetamol in our hospital would save around £ 38,711 (€ 43,960 or US$ 47,498) per annum.

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Resumen En el presente trabajo se plantea un análisis biomecánico de una prótesis de cadera bajo condiciones de cargas estáticas asociadas a actividades cotidianas, en el cual se comparan tres materiales metálicos para la fabricación de una prótesis personalizada a partir de imágenes médicas. Se utilizaron plataformas en la nube de diseño asistido por computadora y de análisis por elementos finitos. Se diseñaron dos modelos de la prótesis a analizar, uno hueco y otro sólido mediante curvas spline paramétricas. Para el análisis biomecánico se requirió un tamaño de malla de 2,537,684 de elementos tetraédricos y 471,335 nodos para estudiar siete casos de posturas para una persona de 75 kg de peso, mismos que se analizaron tomando como materiales base acero inoxidable 316L, aleación Ti-6AL-4V y L-605. Se observó que con actividades tales como trotar, subir y bajar escaleras los materiales 316L y L-605, presentan el riesgo de deformación plástica e inclusive fractura. Los resultados mostraron que el material más idóneo para la fabricación de este tipo de prótesis es el Ti-6Al-4V, además de que este nos permite realizar modelos tanto sólidos como huecos, suponiendo este último, un ahorro de material y proporcionando mayor ligereza en la prótesis.

Abstract This paper shows a biomechanical analysis of a hip prosthesis under conditions of static loads associated with daily activities. For which it compared three metallic materials for the manufacture of a customized prosthesis from medical images, it was used cloud platforms with computer-aided design and finite element analysis. Two models of prosthesis one hollow and the other one solid using parametric spline curves were designed and analyzed. The biomechanical analysis required a mesh size consisting of 2,537,684 tetrahedral elements and 471,335 nodes to study seven cases of postures for a person weighing 75 kg. These cases were analyzed based on 316L stainless steel, Ti-6AL-4V alloy, and another L-605 alloy. It was observed that with activities such as jogging, climbing and descending stairs, materials 316L, and L-605 present the risk of plastic deformation and even fracture. The results show that the most suitable material for the manufacture of this type of prosthesis is the Ti-6Al-4V, which allows us to make both solid and hollow models. Assuming this last material is saved and improves the prosthesis lightness.

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Here we demonstrate a simple method for the organic sonosynthesis of stable Iron Carbide@Iron Oxide core-shell nanoparticles (ICIONPs) stabilized by oleic acid surface modification. This robust synthesis route is based on the sonochemistry reaction of organometallic precursor like Fe(CO)5 in octanol using low intensity ultrasonic bath. As obtained, nanoparticles diameter sizes were measured around 6.38 nm ±â€¯1.34 with a hydrodynamic diameter around 25 nm and an estimated polydispersity of 0.27. Core-Shell structure of nanoparticles was confirmed using HR-TEM and XPS characterization tools in which a core made up of iron carbide (Fe3C) and a shell of magnetite (γ-Fe2O3) was found. The overall nanoparticle presented ferromagnetic behavior at 4 K by SQUID. With these characteristics, the ICIONPs can be potentially used in various applications such as theranostic agent due to their properties obtained from the iron oxides and iron carbide phases.

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Modulation of opioid receptors is the primary choice for pain management and structural information studies have gained new horizons with the recently available X-ray crystal structures. Herkinorin is one of the most remarkable salvinorin A derivative with high affinity for the mu opioid receptor, moderate selectivity and lack of nitrogen atoms on its structure. Surprisingly, binding models for herkinorin are lacking. In this work, we explore binding models of herkinorin using automated docking, molecular dynamics simulations, free energy calculations and available experimental information. Our herkinorin D-ICM-1 binding model predicted a binding free energy of -11.52 ± 1.14 kcal mol-1 by alchemical free energy estimations, which is close to the experimental values -10.91 ± 0.2 and -10.80 ± 0.05 kcal mol-1 and is in agreement with experimental structural information. Specifically, D-ICM-1 molecular dynamics simulations showed a water-mediated interaction between D-ICM-1 and the amino acid H2976.52, this interaction coincides with the co-crystallized ligands. Another relevant interaction, with N1272.63, allowed to rationalize herkinorin's selectivity to mu over delta opioid receptors. Our suggested binding model for herkinorin is in agreement with this and additional experimental data. The most remarkable observation derived from our D-ICM-1 model is that herkinorin reaches an allosteric sodium ion binding site near N1503.35. Key interactions in that region appear relevant for the lack of ß-arrestin recruitment by herkinorin. This interaction is key for downstream signaling pathways involved in the development of side effects, such as tolerance. Future SAR studies and medicinal chemistry efforts will benefit from the structural information presented in this work.

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El vitiligo y la psoriasis se observan con frecuencia en la consulta dermatológica; sin embargo, pese a su alta prevalencia, no es frecuente que ambas se encuentren en un mismo paciente. Presentamos los casos de tres pacientes que exhiben esta situación y realizamos una revisión de la literatura, en cuanto a los aspectos fisiopatogénicos comunes, que podrían contribuir a generar la coexistencia de estas entidades.

Vitiligo and psoriasis are commonly seen in the dermatology clinic; yet, despite their high prevalence, it is infrequent to find them together in the same patient. We report three cases exhibiting this situation and we do a literature review regarding common pathophysiologic aspects that could generate the coexistence of these entities.

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El vitiligo y la psoriasis se observan con frecuencia en la consulta dermatológica; sin embargo, pese a su alta prevalencia, no es frecuente que ambas se encuentren en un mismo paciente. Presentamos los casos de tres pacientes que exhiben esta situación y realizamos una revisión de la literatura, en cuanto a los aspectos fisiopatogénicos comunes, que podrían contribuir a generar la coexistencia de estas entidades.(AU)

Vitiligo and psoriasis are commonly seen in the dermatology clinic; yet, despite their high prevalence, it is infrequent to find them together in the same patient. We report three cases exhibiting this situation and we do a literature review regarding common pathophysiologic aspects that could generate the coexistence of these entities.(AU)