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In several cases, it is desirable to have prototypes of low-cost fabrication and adequate performance. In academic laboratories and industries, miniature and microgrippers can be very useful for observations and the analysis of small objects. Piezoelectrically actuated microgrippers, commonly fabricated with aluminum, and with micrometer stroke or displacement, have been considered as Microelectromechanical Systems (MEMS). Recently, additive manufacture using several polymers has also been used for the fabrication of miniature grippers. This work focuses on the design of a piezoelectric-driven miniature gripper, additive manufactured with polylactic acid (PLA), which was modeled using a pseudo rigid body model (PRBM). It was also numerically and experimentally characterized with an acceptable level of approximation. The piezoelectric stack is composed of widely available buzzers. The aperture between the jaws allows it to hold objects with diameters lower than 500 µm, and weights lower than 1.4 g, such as the strands of some plants, salt grains, metal wires, etc. The novelty of this work is given by the miniature gripper's simple design, as well as the low-cost of the materials and the fabrication process used. In addition, the initial aperture of the jaws can be adjusted, by adhering the metal tips in the required position.

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Sudden unexpected death in infancy (SUDI) - defined as the death of a child under 1 year of age du ring sleep with no initially obvious cause - remains one of the most common causes of post-neonatal mortality. Approximately 3,500 infants die annually in the United States from sleep-related deaths. A complex and multifactorial origin is postulated in a vulnerable infant. However, the pathophysiology of SUDI has not been fully understood. Health care providers play a key role in promoting preventive measures described in the literature, which include sleeping in a supine position on a firm surface, avoiding smoking and co-sleeping, promoting breastfeeding, among others. The objective of this re view is to summarize the main epidemiological and physiopathological characteristics of SUDI, and safe sleep-related factors.

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This paper discusses the structure, particle morphology, and optical properties of un-doped ZnO and ZnO doped with Er3+ and Yb3+ lanthanide ion nanoparticles (NPs) through a process denominated sol-gel-hydrothermal. According to the pattern of X-ray diffraction, ZnO:Er and ZnO:Yb is formed by a single-phase wurtzite structure with crystallites sized ~65 nm on average, and Er or Yb dopant ions in the hexagonal structure of ZnO, specifically in its distorted lattice sites. The results also suggest the possible role of oxygen vacancies or Ox- (defects) in the energy transfer from ZnO to the Er or Yb ions with a decrease of 3.18 eV and 3.19 eV in bandgap values to a red shift.

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SrTiO³ nanopowders doped with various percentages of Fe (0, 1, 3, and 5 mol%) was synthesized, determining its chemical and structural properties using X-ray diffraction and X-ray photoelectron spectroscopy. The magnetic properties of the samples were studied using hysteresis curves obtained by an alternating gradient magnetometer. Theoretical calculations within the framework of the density functional theory are also performed to support experimental data. The results indicated that Fe incorporated into de SrTiO³ structure induced intrinsic magnetic properties, which increase as the Fe percentage increase. At 5 mol% of Fe in the sample showed a single-domain state, typical of a ferromagnetic material capable for information storage. This latter result would be due to the reduction of oxygen vacancies as more Fe was added and to the presence of Fe2+ and Fe3+ ions reinforced the magnetic behaviour of the compound.

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Neglected tropical diseases (NTDs) share certain traits: they are parasitic infections, prevailing in tropical environments and affecting marginalized sectors of the population. Six NTDs - ascariasis, cysticercosis, echinococcosis, hookworm infection, onchocerciasis and trichuriasis - all of them endemic in Latin America and the Caribbean (LAC), are analysed in this work. This review aims to discuss key information on the function of excretory/secretory (E/S) proteins from these parasites in their infectivity, pathogeny and diagnosis. The modulation of the host immune system to favour the permanence and survival of the parasite is also discussed. An updated knowledge on the function of E/S molecules in endemic parasitoses in LAC may lead to new approaches for the clinical management and diagnosis of these diseases. In turn, this could allow us to optimize their treatment and make it more affordable - a relevant goal given the economic constraints that the region is facing.

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The better understanding of the global activity of vitamin D has led to an intense search for its involvement in non-skeletal diseases. This article presents an updated review of the relationship between vitamin D and pediatric respiratory pathology. A literature search was performed in PUBMED using free terms and MESH terms: vitamin D, asthma, respiratory system diseases, and bronchiolitis. Stu dies in human patients younger than 18 years and animals, published in English and Spanish until 2017 were included. 507 articles were found, of which 43 were included. Indirect evidence suggests a role of vitamin D and fetal lung maturation. In relation to pediatric pulmonary pathology, studies are scarce and inconclusive. Recent meta-analyses performed with individualized evaluation of the participants shows an important protective role of vitamin D supplementation in the prevention of severe asthma exacerbations and acute viral infections. In bronchiolitis, the results are contradictory, with no clear relationship between plasma levels and severity. There is not enough evidence to assess the benefits of vitamin D supplementation in cystic fibrosis and tuberculosis. A direct relationship between the severity of sleep-related breathing disorders and vitamin D plasma levels has recently been proposed, although the exact mechanisms involved in this association are unknown. Current information suggests that vitamin D supplementation may represent a cost-effective strategy in redu cing important causes of infant morbidity and mortality.

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Active hybrid microspheres were prepared by blending aqueous solutions of gelatine and chitosan with different concentrations of copper nanoparticles (0) (CuNPs) using emulsion-based crosslinking synthesis to obtain hybrid microspheres. The incorporation of CuNPs slightly affected the physical and chemical properties of the films. Microscopic surface structure (SEM), energy dispersive X-ray (EDX) spectroscopy and X-ray diffraction (XRD) analysis confirmed the presence of elemental copper and the crystalline structure of the CuNPs in the hybrid matrix. The surface properties of CuNPs were studied by XPS analyses. The antimicrobial activity of CuNPs coated with chitosan (QO)/gelatine (GE) compared to the QO/GE matrix alone was investigated, using the agar diffusion and culture medium methods in Mueller-Hinton. The evaluation was performed using the Gram-negative bacterium E. coli and the Gram positive bacterium E. faecalis. The investigated microspheres showed antimicrobial activity. Hybrid microspheres with 40 mg of Cu, evaluated in liquid medium, inhibited the growth of E. coli by 56% and of E. faecalis by 40% compared to the matrix hybridised alone; in solid medium, the inhibition was 2.5-fold and 2.6-fold, respectively. Thus, these microspheres are a promising material for applications with medical uses.

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Aedes aegypti is the major vector of a number of arboviruses that cause disease in humans. Without vaccines or pharmaceuticals, pyrethroid insecticides remain the major tool for public health protection. Pyrethroid resistance is now widespread. Replacement substitutions in the voltage-gated sodium channel (vgsc) that reduce the stability of pyrethroid binding account for most of the resistance, but metabolic mechanisms also inactivate pyrethroids. High-throughput sequencing and the A. aegypti L5 annotated physical map has allowed interrogation of the exome for genes and single-nucleotide polymorphisms associated with pyrethroid resistance. We exposed females of A. aegypti from Mexico to a deltamethrin discriminating dose to designate them as resistant (active after 1 h) or susceptible (knocked down with no recovery after 4 h). The vgsc on chromosome 3 had the highest association, followed by genes proximal to vgsc. We identified potential detoxification genes located singly (eg HPX8C) or within clusters in chromosome 2 [three esterase clusters, two of cytochrome P450 monooxygenases (CYP)] and chromosome 3 (one cluster of 16 CYP325 and seven CYP9 genes). Deltamethrin resistance in A. aegypti is associated with mutations in the vgsc gene and a large assortment of genes.

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Resumen: El mejor entendimiento sobre la actividad global de la vitamina D, ha llevado a una intensa búsque da de sus implicancias en enfermedades no esqueléticas. En este artículo se presenta una revisión actualizada de la relación entre la vitamina D y la patología respiratoria pediátrica. Se realizó una búsqueda bibliográfica en PUBMED utilizando términos libres y MESH: vitamina D, enfermedades del sistema respiratorio, asma, bronquiolitis. Se seleccionó estudios en humanos menores de 18 años y animales, publicados en inglés y español hasta el 2017. Se encontraron 507 artículos, de los cuales se incluyeron 43. Evidencia indirecta apunta hacia un rol de la vitamina D y la maduración pulmonar fetal. En relación a la patología pulmonar pediátrica, los estudios son escasos y poco concluyentes. Nuevos meta - análisis, con evaluación individualizada de los participantes, muestran un importante rol protector de la suplementación en la prevención de exacerbaciones asmáticas severas e infecciones virales agudas. En bronquiolitis los resultados son contradictorios, sin relación clara entre niveles plasmáticos y severidad. No existe suficiente evidencia que evalué los beneficios en fibrosis quística y tuberculosis. Recientemente se ha propuesto una relación directa entre la severidad de los trastornos respiratorios del sueño y los niveles plasmáticos de vitamina D, aunque se desconoce los mecanismos exactos involucrados a esta asociación. La información actual permite suponer que la suplementación de vitamina D puede representar una estrategia costo - efectiva en la reducción de importantes causas de morbimortalidad infantil.

Abstract: The better understanding of the global activity of vitamin D has led to an intense search for its involvement in non-skeletal diseases. This article presents an updated review of the relationship between vitamin D and pediatric respiratory pathology. A literature search was performed in PUBMED using free terms and MESH terms: vitamin D, asthma, respiratory system diseases, and bronchiolitis. Stu dies in human patients younger than 18 years and animals, published in English and Spanish until 2017 were included. 507 articles were found, of which 43 were included. Indirect evidence suggests a role of vitamin D and fetal lung maturation. In relation to pediatric pulmonary pathology, studies are scarce and inconclusive. Recent meta-analyses performed with individualized evaluation of the participants shows an important protective role of vitamin D supplementation in the prevention of severe asthma exacerbations and acute viral infections. In bronchiolitis, the results are contradictory, with no clear relationship between plasma levels and severity. There is not enough evidence to assess the benefits of vitamin D supplementation in cystic fibrosis and tuberculosis. A direct relationship between the severity of sleep-related breathing disorders and vitamin D plasma levels has recently been proposed, although the exact mechanisms involved in this association are unknown. Current information suggests that vitamin D supplementation may represent a cost-effective strategy in redu cing important causes of infant morbidity and mortality.

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Objetivos: Determinar la precisión de la angiotomografía renal (ATR) en la evaluación del sistema arterial y las variantes anatómicas en el donante vivo, con la correlación con su ablación quirúrgica. Materiales y métodos: Se evaluaron retrospectivamente los pacientes sometidos a nefrectomía laparoscópica como donantes vivos renales y sus ATR, entre 2014 y 2016 en nuestra Institución. Se utilizó análisis estadístico descriptivo para presentar los resultados. En la ATR se evaluaron: número de arterias renales principales, presencia y número de arterias polares y alteraciones del calibre de la arteria renal. Resultados: Se incluyeron 21 pacientes sometidos a nefrectomía laparoscópica como donantes vivos, 10 mujeres y 11 hombres (entre 23 y 61 años). En todos los casos se realizó la ablación del riñón izquierdo. De los 21 pacientes analizados, 15 no presentaron variantes anatómicas ni alteraciones del calibre en la ATR (una arteria renal principal, sin polares). Estos mismos hallazgos se certificaron en la ablación. En un caso, la ATR observó doble arteria renal principal con el mismo hallazgo quirúrgico; y en tres casos la ATR reconoció una única arteria polar, las cuales se corroboraron en la ablación. En estos 19 casos se demostró correlación entre la ATR y la ablación, con una precisión del 90,4% En los 2 casos restantes, hubo discrepancias. Conclusión: El conocimiento detallado del sistema arterial es necesario para la planificación quirúrgica de la nefrectomía laparoscópica del donante vivo renal. La angiotomografía renal constituye el método de elección para su evaluación, demostrando muy buena correlación entre sus hallazgos y los de la ablación.

Objective: To determine the accuracy of computed tomography renal angiography (CTRA) in the assessment and diagnosis of arterial vascular anatomy of the kidney and its variations in living kidney donors, with its correlation in harvesting kidneys. Materials and methods: Patients who had undergone laparoscopic nephrectomy as living kidney donors and their CTRA were retrospectively evaluated between 2014 and 2016 in our institution. Results are presented using statistical descriptive analysis. The following were assessed in the CTRA report: number of main renal arteries, presence and number of accessory polar arteries, and anomalies related to renal artery calibre. Results: Of the 21 patients that had undergone laparoscopic nephrectomy as living donors, there were 10 female and 11 male donors (age range 23 - 61 years). Renal harvesting included left kidney in all cases. In 15 cases, no anatomical variations or arterial renal dilations were found in computed tomography renal angiography (CTRA): (one main renal artery, without accessories arteries). The same findings were certified during the surgery. In one case CTRA showed a double renal artery, and the same finding occurred in the surgical harvesting; and three cases in which one single polar accessory artery was certified at surgery. An overall accuracy of 90.4% for CTRA was obtained in 19 cases. In the remaining 2 cases, a discrepancy was found. Conclusion: Detailed knowledge of the renal arterial anatomy is important for the preoperative evaluation of the laparoscopic nephrectomy in living renal donors. Computed tomography renal angiography (CTRA) is the technique of choice for these patients, as it demonstrates a high correlation between tomography findings and surgery harvesting.

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