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Nanoparticle exsolution has emerged as a versatile method to functionalize oxides with robust metallic nanoparticles for catalytic and energy applications. By modifying certain external parameters during thermal reduction (temperature, time, reducing gas), some morphological and/or compositional properties of the exsolved nanoparticles can be tuned. Here, it is shown how the application of high pressure (<100 bar H2) enables the control of the exsolution of ternary FeCoNi alloyed nanoparticles from a double perovskite. H2 pressure affects the lattice expansion and the nanoparticle characteristics (size, population, and composition). The composition of the alloyed nanoparticles could be controlled, showing a reversal of the expected thermodynamic trend at 10 and 50 bar, where Fe becomes the main component instead of Ni. In addition, pressure drastically lowers the exsolution temperature to 300 °C, resulting in unprecedented highly-dispersed and small-sized nanoparticles with a similar composition to those obtained at 600 °C and 10 bar. The mechanisms behind the effects of pressure on exsolution are discussed, involving kinetic, surface thermodynamics, and lattice-strain factors. A volcano-like trend of the exsolution extent suggests that competing pressure-dependent mechanisms govern the process. Pressure emerges as a new design tool for metallic nanoparticle exsolution enabling novel nanocatalysts and surface-functionalized materials.
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Among renewable energies, wind and solar are inherently intermittent and therefore both require efficient energy storage systems to facilitate a round-the-clock electricity production at a global scale. In this context, concentrated solar power (CSP) stands out among other sustainable technologies because it offers the interesting possibility of storing energy collected from the sun as heat by sensible, latent, or thermochemical means. Accordingly, continuous electricity generation in the power block is possible even during off-sun periods, providing CSP plants with a remarkable dispatchability. Sensible heat storage has been already incorporated to commercial CSP plants. However, because of its potentially higher energy storage density, thermochemical heat storage (TCS) systems emerge as an attractive alternative for the design of next-generation power plants, which are expected to operate at higher temperatures. Through these systems, thermal energy is used to drive endothermic chemical reactions, which can subsequently release the stored energy when needed through a reversible exothermic step. This review analyzes the status of this prominent energy storage technology, its major challenges, and future perspectives, covering in detail the numerous strategies proposed for the improvement of materials and thermochemical reactors. Thermodynamic calculations allow selecting high energy density systems, but experimental findings indicate that sufficiently rapid kinetics and long-term stability trough continuous cycles of chemical transformation are also necessary for practical implementation. In addition, selecting easy-to-handle materials with reduced cost and limited toxicity is crucial for large-scale deployment of this technology. In this work, the possible utilization of materials as diverse as metal hydrides, hydroxides, or carbonates for thermochemical storage is discussed. Furthermore, special attention is paid to the development of redox metal oxides, such as Co3O4/CoO, Mn2O3/Mn3O4, and perovskites of different compositions, as an auspicious new class of TCS materials due to the advantage of working with atmospheric air as reactant, avoiding the need of gas storage tanks. Current knowledge about the structural, morphological, and chemical modifications of these solids, either caused during redox transformations or induced wittingly as a way to improve their properties, is revised in detail. In addition, the design of new reactor concepts proposed for the most efficient use of TCS in concentrated solar facilities is also critically considered. Finally, strategies for the harmonic integration of these units in functioning solar power plants as well as the economic aspects are also briefly assessed.
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Memristive devices are among the most prominent candidates for future computer memory storage and neuromorphic computing. Though promising, the major hurdle for their industrial fabrication is their device-to-device and cycle-to-cycle variability. These occur due to the random nature of nanoionic conductive filaments, whose rupture and formation govern device operation. Changes in filament location, shape, and chemical composition cause cycle-to-cycle variability. This challenge is tackled by spatially confining conductive filaments with Ni nanoparticles. Ni nanoparticles are integrated on the bottom La0.2 Sr0.7 Ti0.9 Ni0.1 O3- δ electrode by an exsolution method, in which, at high temperatures under reducing conditions, Ni cations migrate to the perovskite surface, generating metallic nanoparticles. This fabrication method offers fine control over particle size and density and ensures strong particle anchorage in the bottom electrode, preventing movement and agglomeration. In devices based on amorphous SrTiO3 , it is demonstrated that as the exsolved Ni nanoparticle diameter increases up to ≈50 nm, the ratio between the ON and OFF resistance states increases from single units to 180 and the variability of the low resistance state reaches values below 5%. Exsolution is applied for the first time to engineer solid-solid interfaces extending its realm of application to electronic devices.
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Many relevant high-temperature chemical processes require the use of oxide-supported metallic nanocatalysts. The harsh conditions under which these processes operate can trigger catalyst degradation via nanoparticle sintering, carbon depositions or poisoning, among others. This primarily affects metallic nanoparticles created via deposition methods with low metal-support interaction. In this respect, nanoparticle exsolution has emerged as a promising method for fabricating oxide-supported nanocatalysts with high interaction between the metal and the oxide support. This is due to the mechanism involved in nanoparticle exsolution, which is based on the migration of metal cations in the oxide support to its surface, where they nucleate and grow as metallic nanoparticles partially embedded in the oxide. This anchorage confers high robustness against sintering or coking-related problems. For these reasons, exsolution has attracted great interest in the last few years. Multiple works have been devoted to proving the high catalytic stability of exsolved metallic nanoparticles in several applications for high-temperature energy storage and conversion. Additionally, considerable attention has been directed towards understanding the underlying mechanism of metallic nanoparticle exsolution. However, this growing field has not been limited to these types of studies and recent discoveries at the forefront of materials design have opened new research avenues. In this work, we define six new trends in nanoparticle exsolution, taking a tour through the most important advances that have been recently reported.
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Oxygen transport membranes (OTMs) are a promising oxygen production technology with high energy efficiency due to the potential for thermal integration. However, conventional perovskite materials of OTMs are unstable in CO2 atmospheres, which limits their applicability in oxycombustion processes. On the other hand, some dual-phase membranes are stable in CO2 and SO2 without permanent degradation. However, oxygen permeation is still insufficient; therefore, intensive research focuses on boosting oxygen permeation. Here, we present a novel dual-phase membrane composed of an ion-conducting fluorite phase (Ce0.8Tb0.2O2-δ, CTO) and an electronic-conducting spinel phase (Co2MnO4, CMO). CMO spinel exhibits high electronic conductivity (60 S·cm-1 at 800 °C) compared to other spinels used in dual-phase membranes, i.e., 230 times higher than that of NiFe2O4 (NFO). This higher conductivity ameliorates gas-solid surface exchange and bulk diffusion mechanisms. By activating the bulk membrane with a CMO/CTO porous catalytic layer, it was possible to achieve an oxygen flux of 0.25 mL·min-1·cm-2 for the 40CMO/60CTO (%vol), 680 µm-thick membrane at 850 °C even under CO2-rich environments. This dual-phase membrane shows excellent potential as an oxygen transport membrane or oxygen electrode under high CO2 and oxycombustion operation.
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Aortic dissection is a rare condition with a high mortality rate, the clinical manifestations of which depend on the involvement of aortic branches. We describe the case of a male patient with neurological deficits accompanied by dorsal-lumbar pain and exuberant sympathetic hyperactivity, diagnosed with ascending and descending aorta dissection, initially managed in the prehospital setting. This case reinforces the importance of maintaining high levels of suspicion for rare causes of cerebrovascular accidents.
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BACKGROUND: Greater trochanteric pain syndrome (GTPS) is a prevalent cause of lateral hip pain that often leads to significant functional limitations. Conservative treatment options include physical therapy, pharmacological treatment, and more invasive techniques such as corticosteroid injections. However, despite the high success rates reported with corticosteroid injections, a significant number of patients have their symptoms persist or recur. OBJECTIVES: In this case series, we present the outcomes of nine patients with GTPS who underwent ultrasound-guided bipolar pulsed radiofrequency targeting the trochanteric branches of the femoral nerve. We aim to discuss the effectiveness and safety of this approach. MATERIAL AND METHODS: Eligible patients referred to our centre underwent ultrasound-guided bipolar pulsed radiofrequency aimed at the trochanteric branches of the femoral nerve. The procedure consisted of one cycle at 42°C for six minutes, followed by the injection of ropivacaine (0.2%, 3 mL) and dexamethasone (12 mg). The Brief Pain Inventory - Short Form (BPI-sf) and Lequesne Algofunctional Index (LAI) were used before the procedure and at the third and sixth months post-procedure. We monitored immediate and late complications, as well as adverse effects. RESULTS AND DISCUSSION: Our results indicate a favourable outcome for most patients, with an average pain reduction of 76.51% according to their report of the BPI-sf. Additionally, eight out of nine patients experienced at least 50% relief. These findings align with a previous case series, which reported a similar average pain reduction. Before the procedure, most patients were classified as "extremely severe" in the LAI, with an average score of 18.17. Although there was only a slight reduction of 16.84% at the six-month follow-up, this suggests a potential improvement in their functional status. We did not observe any immediate complications or adverse effects after the procedure, nor were any reported at the subsequent follow-ups, which is consistent with existing literature. CONCLUSIONS: Our study suggests that ultrasound-guided bipolar pulsed radiofrequency treatment is a promising minimally invasive technique for GPTS, especially for patients who do not respond to conservative treatments. Although our case series provides some evidence of effectiveness and safety, further controlled studies on a larger scale are necessary, particularly to compare this intervention with the use of corticosteroid injections alone.
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Exsolution has emerged as a promising method for generating metallic nanoparticles, whose robustness and stability outperform those of more conventional deposition methods, such as impregnation. In general, exsolution involves the migration of transition metal cations, typically perovskites, under reducing conditions, leading to the nucleation of well-anchored metallic nanoparticles on the oxide surface with particular properties. There is growing interest in exploring alternative methods for exsolution that do not rely on high-temperature reduction via hydrogen. For example, utilizing electrochemical potentials or plasma technologies has shown promising results in terms of faster exsolution, leading to better dispersion of nanoparticles under milder conditions. To avoid limitations in scaling up exhibited by electrochemical cells and plasma-generation devices, we proposed a method based on pulsed microwave (MW) radiation to drive the exsolution of metallic nanoparticles. Here, we demonstrate the H2-free MW-driven exsolution of Ni nanoparticles from lanthanum strontium titanates, characterizing the mechanism that provides control over nanoparticle size and dispersion and enhanced catalytic activity and stability for CO2 hydrogenation. The presented method will enable the production of metallic nanoparticles with a high potential for scalability, requiring short exposure times and low temperatures.
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Cardiac arrest (CA) in the operating room is rare. Among known perioperative CA causes, Takotsubo syndrome (TTS) is a well-recognized one. Perioperative TTS is more common than existing reported cases therefore anesthesiologists should be aware of its diagnosis and management. TTS is an acquired and self-limited stress cardiomyopathy usually triggered by a precipitating stress factor and should be considered in any hospitalized patient presenting with symptoms such as acute coronary syndrome, cardiac arrhythmias or CA. A 67-year-old woman presented for lumbar discectomy in knee-chest position suffered CA two hours after the beginning of surgery. After a thorough examination, TTS was determined as the cause. This case report highlights the importance of TTS as a differential diagnosis of CA in the intraoperative setting as well as the usefulness of multimodal monitoring with cerebral monitoring to assist the prompt pulseless electric activity diagnosis. To our knowledge, this is the first case report in such circumstances.
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Viral metagenomics (viromics) has reshaped our understanding of DNA viral diversity, ecology, and evolution across Earth's ecosystems. However, viromics now needs approaches to link newly discovered viruses to their host cells and characterize them at scale. This study adapts one such method, sequencing-enabled viral tagging (VT), to establish "Viral Tag and Grow" (VT + Grow) to rapidly capture and characterize viruses that infect a cultivated target bacterium, Pseudoalteromonas. First, baseline cytometric and microscopy data improved understanding of how infection conditions and host physiology impact populations in VT flow cytograms. Next, we extensively evaluated "and grow" capability to assess where VT signals reflect adsorption alone or wholly successful infections that lead to lysis. Third, we applied VT + Grow to a clonal virus stock, which, coupled to traditional plaque assays, revealed significant variability in burst size-findings that hint at a viral "individuality" parallel to the microbial phenotypic heterogeneity literature. Finally, we established a live protocol for public comment and improvement via protocols.io to maximally empower the research community. Together these efforts provide a robust foundation for VT researchers, and establish VT + Grow as a promising scalable technology to capture and characterize viruses from mixed community source samples that infect cultivable bacteria.
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We have evaluated the in vitro activity of anidulafungin (AFG) against 31 strains of Candida parapsilosis sensu stricto by using broth microdilution, disk diffusion, and minimal fungicidal concentration (MFC) determination procedures. The two first methods showed a high level of activity of the drug, while MFCs were 1 to 5 dilutions higher than their corresponding MICs. To assess if MICs were predictive of in vivo outcomes, six strains representing different AFG MICs (0.12 to 2 µg/ml) were tested in a murine model of disseminated infection treated with different doses of the drug (1, 5, or 10 mg/kg of body weight). AFG was able to prolong the survival of mice infected with all the strains tested but was able to reduce the tissue burden of those mice infected only with the strains that showed the lowest MIC (0.12 µg/ml).
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Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candida/patogenicidade , Candidíase/sangue , Candidíase/tratamento farmacológico , Equinocandinas/uso terapêutico , Mananas/sangue , beta-Glucanas/sangue , Anidulafungina , Animais , Estimativa de Kaplan-Meier , Masculino , Camundongos , Testes de Sensibilidade MicrobianaRESUMO
This work presents a method for measuring and computing violin-body directional frequency responses, which are used for violin sound synthesis. The approach is based on a frame-weighted deconvolution of excitation and response signals. The excitation, consisting of bowed glissandi, is measured with piezoelectric transducers built into the bridge. Radiation responses are recorded in an anechoic chamber with multiple microphones placed at different angles around the violin. The proposed deconvolution algorithm computes impulse responses that, when convolved with any source signal (captured with the same transducer), produce a highly realistic violin sound very similar to that of a microphone recording. The use of motion sensors allows for tracking violin movements. Combining this information with the directional responses and using a dynamic convolution algorithm, helps to improve the listening experience by incorporating the violinist motion effect in stereo.
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Acústica/instrumentação , Música , Som , Algoritmos , Simulação por Computador , Desenho de Equipamento , Modelos Teóricos , Movimento (Física) , Processamento de Sinais Assistido por Computador , Espectrografia do Som , Transdutores , VibraçãoRESUMO
Mn oxides are promising materials for thermochemical heat store, but slow reoxidation of Mn3 O4 to Mn2 O3 limits efficiency. In contrast, (Mn1- x Fex )3 O4 oxides show an enhanced transformation rate, but fundamental understanding of the role played by Fe cations is lacking. Here, nanoscale characterization of Fe-doped Mn oxides is performed to elucidate how Fe incorporation influences solid-state transformations. X-ray diffraction reveals the presence of two distinct spinel phases, cubic jacobsite and tetragonal hausmannite for samples with more than 10% of Fe. Chemical mapping exposes wide variation of Fe content between grains, but an even distribution within crystallites. Due to the similarities of spinels structures, high-resolution scanning transmission electron microscopy cannot discriminate unambiguously between them, but Fe-enriched crystallites likely correspond to jacobsite. In situ X-ray absorption spectroscopy confirms that increasing Fe content up to 20% boosts the reoxidation rate, leading to the transformation of Mn2+ in the spinel phase to Mn3+ in bixbyite. Extended X-ray absorption fine structure shows that FeO length is larger than MnO, but both electron energy loss spectroscopy and X-ray absorption near edge structure indicate that iron is always present as Fe3+ in octahedral sites. These structural modifications may facilitate ionic diffusion during bixbyite formation.
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Increasing the capacity and kinetics of oxygen exchange in solid oxides is important to improve the performance of numerous energy-related materials, especially those for the solar-to-fuel technology. Dual-phase metal oxide composites of La0.65Sr0.35MnO3-x%CeO2, with x = 0, 5, 10, 20, 50, and 100, have been experimentally investigated for oxygen exchange and CO2 splitting via thermochemical redox reactions. The prepared metal oxide powders were tested in a temperature range from 1000 to 1400 °C under isothermal and two-step cycling conditions relevant for solar thermochemical fuel production. We reveal synergetic oxygen exchange of the dual-phase composite La0.65Sr0.35MnO3-CeO2 compared to its individual components. The enhanced oxygen exchange in the composite has a beneficial effect on the rate of oxygen release and the total CO produced by CO2 splitting, while it has an adverse effect on the maximum rate of CO evolution. Ex situ Raman and XRD analyses are used to shed light on the relative oxygen content during thermochemical cycling. Based on the relative oxygen content in both phases, we discuss possible mechanisms that can explain the observed behavior. Overall, the presented findings highlight the beneficial effects of dual-phase composites in enhancing the oxygen exchange capacity of redox materials for renewable fuel production.
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Introducción: La osteoartritis es una enfermedad articular crónica degenerativa con componente inflamatorio caracterizado por degeneración y pérdida progresiva del cartílago hialino y hueso subcondral y daño del tejido sinovial. Objetivo: Describir los aspectos clínicos y epidemiológicos de los pacientes con diagnóstico de osteoartritis en el Hospital Provincial de Zaire en la República de Angola, en el período comprendido entre septiembre de 2021 a septiembre de 2022. Método: Se realizó un estudio descriptivo, de cohorte longitudinal, con datos del Departamento de Ortopedia y Traumatología de dicha institución. El universo estuvo constituido por 489 pacientes, la muestra del estudio quedó conformada por n꓿167. Se realizaron pruebas de correlación bivariable con el análisis del coeficiente de correlación de Pearson. Resultados: El grupo etario predominante fue de 61 a 70 años (28,7 %), con predominio del sexo femenino (58,1 %), con un tiempo de evolución mayor a 5 años (35,9 %), la articulación mayormente afectada fue la rodilla con 62 pacientes. Se demostró que existe una correlación positiva considerable entre el tiempo de evolución de la enfermedad y el grado de discapacidad, mediante valor del coeficiente de Pearson (0,407), resultado que muestra significación estadística. Conclusiones: La osteoartritis es una enfermedad degenerativa de etiología variada que se presenta en edades tempranas, con mayor frecuencia en el sexo femenino asociada a la articulación de la rodilla, existiendo correlación entre el tiempo de evolución con el grado de discapacidad que produce.
Introduction: Osteoarthritis is a chronic degenerative joint disease, with an inflammatory component included, its characterized by degeneration and progressive loss of hyaline cartilage and subchondral bone and also for synovial tissue damage. Objective: To describe the clinical and epidemiological aspects of patients diagnosed with osteoarthritis at the Provincial Hospital of Zaire in the Republic of Angola, from September 2021 to September 2022. Method: A descriptive, longitudinal cohort study was carried out using the data gathered from the Department of Orthopedics and Traumatology of the institution. The universe consisted of 489 patients and the study sample consisted of n꓿167. Bivariate correlation tests were performed using the Pearson's correlation coefficient analysis. Results: The predominant age group was 61 to 70 years old (28.7%), with women sex as predominant (58.1%), with an evolution time of more than 5 years (35.9%), and the knee was the most affected joint (observed in 62 patients). A considerable positive correlation between the time of the disease evolution and the degree of disability was demonstrated using the Pearson's coefficient value (0.407), value that shows a great statistical significance. Conclusions: Osteoarthritis is a degenerative disease of varied etiology that occurs at early ages, more frequently in the female sex associated with the knee joint, and there is a correlation between the time of evolution and the degree of disability produces by the disease.
Introdução: A osteoartrite é uma doença articular degenerativa crônica com componente inflamatório caracterizada por degeneração e perda progressiva da cartilagem hialina e lesão do osso subcondral e tecido sinovial. Objetivo: Descrever os aspectos clínicos e epidemiológicos dos pacientes diagnosticados com osteoartrite no Hospital Provincial do Zaire na República de Angola, no período de setembro de 2021 a setembro de 2022. Método: Foi realizado um estudo descritivo, de coorte, longitudinal, com dados do Departamento de Ortopedia e Traumatologia da referida instituição. O universo foi composto por 489 pacientes, a amostra do estudo foi composta por n꓿167. Os testes de correlação bivariada foram realizados por meio da análise do coeficiente de correlação de Pearson. Resultados: A faixa etária predominante foi de 61 a 70 anos (28,7%), com predominância do sexo feminino (58,1%), com tempo de evolução superior a 5 anos (35,9%), a articulação mais acometida foi o joelho com 62 pacientes. Foi demonstrado que existe uma correlação positiva considerável entre o tempo de evolução da doença e o grau de incapacidade, através do valor do coeficiente de Pearson (0,407), resultado que apresenta significância estatística. Conclusões: A osteoartrite é uma doença degenerativa de etiologia variada que ocorre em idade precoce, mais frequentemente no sexo feminino associada à articulação do joelho, havendo correlação entre o tempo de evolução com o grau de incapacidade que produz.
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RESUMEN El riesgo preconcepcional está condicionado por una serie de factores, enfermedades o circunstancias únicas o asociadas que pueden repercutir desfavorablemente en el binomio madre / hijo durante la gestación, parto o puerperio. La prevención de la enfermedad y la muerte durante el proceso de reproducción, es uno de los pilares fundamentales para el desarrollo de la salud reproductiva. La morbilidad materna constituye uno de los aspectos más importantes para reflexionar. El objetivo de esta investigación es valorar la influencia del riesgo preconcepcional en la salud materna. Es indispensable, no solo en la atención de las gestantes, sino también para aquellas mujeres que desean ser madres en algún momento de su vida. Se ha adoptado un nuevo enfoque hacia el riesgo preconcepcional con acciones que contribuyan a mejorar la salud sexual y reproductiva en esta etapa en la vida de hombres y mujeres.
ABSTRACT Preconception risk is conditioned by a series of factors, diseases or unique or associated circumstances that can have an unfavorable impact on the mother - child binomial during pregnancy, delivery or puerperium. The prevention of disease and death during the reproductive process is one of the fundamental pillars for the development of reproductive health. Maternal morbidity is one of the most important aspects to reflect on. The objective of this research is to assess the influence of preconception risk on maternal health. It is essential, not only in the care of pregnant women, but also for those women who want to be mothers at some point in their life. A new approach has been adopted towards preconception risk with actions that contribute to improve sexual and reproductive health at this stage in the lives of men and women.
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Mortalidade Materna , Cuidado Pré-Concepcional , Saúde MaternaRESUMO
RESUMEN La formación integral de los universitarios, a través de los diferentes programas, los cursos propios, optativos / electivos, con el macrocurrículo, el microcurrículo y las diferentes mallas de formación de cada carrera, garantizan un profesional preparado, con amplios recursos para su desempeño posterior. Los cursos propios están bien establecidos por las asignaturas rectoras en cada semestre, y los optativos / electivos pueden ser preestablecidos en el colectivo de asignatura. El objetivo principal es enriquecer el acervo de cada educando. En la presente comunicación se destacó la importancia de la formación de promotores de salud en los estudiantes de las Ciencias Médicas a través de los cursos optativos / electivos. Se aspira a una formación integral del educando que se encuentra en las universidades cubanas, y que el conocimiento científico les permita, una vez graduados, brindar una atención holística a la población en el radio de acción que les corresponda.
ABSTRACT Comprehensive training of university students through the different programs, their own optional or elective courses, the macro-curriculum, the micro-curriculum and the different training curriculums of each career guarantee well-prepared professionals, with ample resources for their subsequent performance. The own courses are well-established by the guiding subjects in each semester, and the optional or elective ones can be pre-established in the subject group. The main objective is to enrich the individual wealth of each student. In this communication, the importance of training health promoters in Medical Sciences students through the optional or elective courses was highlighted. A comprehensive training of the student found in Cuban universities is aspired, as well as that their scientific knowledge, once they graduate, allows them to provide a holistic attention to the population in the radius of action that corresponds to them.
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Relações Comunidade-Instituição , Conhecimento , Desempenho Físico FuncionalRESUMO
Introducción: El síndrome de Lowe o síndrome oculocerebrorenal es un trastorno multisistémico. Es una enfermedad rara e infrecuente. Objetivo: Exponer un caso clínico típico, con fracaso renal controlado sin método dialítico y que de manera tardía en su adolescencia se diagnostica con síndrome de Lennox-Gastaut. Presentación caso: Adolescente masculino de 18 años nacido de un embarazo sin riesgo y parto por cesárea, macrofeto. Desde el nacimiento, con diagnóstico perinatal de catarata congénita y evolutivamente glaucoma bilateral con tratamiento conservador. A partir del primer año de vida padece de acidosis tubular y síndrome de Fanconi con evolución a una enfermedad renal crónica. Relacionado todo con retraso del desarrollo psicomotor, discapacidad intelectual, estereotipias, síntomas obsesivos compulsivos y depresión. De manera tardía, a los 10 años tuvo inicio de crisis epilépticas de varios tipos con predominio de las tónicas durante el sueño y en vigilia, frecuentes, con electroencefalograma característico de síndrome Lennox-Gastaut. Tuvo atención interdisciplinaria y evolución clínica estable hasta la edad adulta cumplida. El estudio molecular de ADN materno y del niño confirmaron la mutación c2224_2226 del GTA (exón 19), delección de valina en la posición 742 del cromosoma X del OCRL 1, que ratifica el síndrome de Lowe. Conclusiones: El Síndrome de Lowe, es un trastorno multisistémico, ligado al cromosoma X y frecuente en varones. Clínicamente se caracteriza por alteraciones oftalmológicas, renales y neurológicas(AU)
Introduction: Lowe syndrome or oculocerebrorenal syndrome is a multisystemic disorder. It's a rare and uncommon disease. Objective: Show a typical clinical case, with controlled renal failure without dialytic method and that late in the adolescence is diagnosed with Lennox-Gastaut syndrome. Case presentation: 18-year-old male adolescent born of a risk-free pregnancy and cesarean delivery, with macrosomia. From birth, he had a perinatal diagnosis of congenital cataract and evolutionarily bilateral glaucoma with conservative treatment. From the first year of life he suffers from tubular acidosis and Fanconi syndrome with an evolution to chronic kidney disease. All of these were related to delayed psychomotor development, intellectual disability, stereotypies, obsessive-compulsive symptoms and depression. Lately, at 10 years old, epileptic seizures of various types with predominance of tonic ones during sleep and wakefulness began; they were frequent, with characteristic electroencephalogram of Lennox-Gastaut syndrome. He had interdisciplinary care and stable clinical evolution into adulthood. The molecular study of the mother and child DNA confirmed the c2224_2226 mutation of GTA (exon 19), valine deletion at position 742 of the X chromosome of OCRL 1, which ratifies Lowe syndrome. Conclusion: Lowe Syndrome is a multisystemic disorder, linked to the X chromosome and common in males. Clinically, it is characterized by ophthalmological, renal and neurological alterations(AU)
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Humanos , Masculino , Adolescente , Catarata/terapia , Doenças Raras/etiologia , Insuficiência Renal Crônica/terapia , Síndrome de Lennox-Gastaut/diagnóstico , Síndrome Oculocerebrorrenal/diagnóstico , Eletroencefalografia/métodosRESUMO
Redox cycles of manganese oxides (Mn2 O3 /Mn3 O4 ) are a promising alternative for thermochemical heat storage systems coupled to concentrated solar power plants as manganese oxides are abundant and inexpensive materials. Although their cyclability for such a purpose has been proved, sintering processes, related to the high-temperature conditions at which charge-discharge cycles are performed, generally cause a cycle-to-cycle decrease in the oxidation rate of Mn3 O4 . To guarantee proper operation, both reactions should present stable reaction rates. In this study, it has been demonstrated that the incorporation of Fe, which is also an abundant material, into the manganese oxides improves the redox performance of this system by increasing the heat storage density, narrowing the redox thermal hysteresis, and, above all, stabilizing and enhancing the oxidation rate over long-term operation, which counteracts the negative effects caused by sintering, although its presence is not avoided.
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Ferro/química , Compostos de Manganês/química , Óxidos/química , Temperatura , Fenômenos Químicos , Cinética , OxirreduçãoRESUMO
RESUMEN Introducción: el control de daños en Ortopedia es aplazar la reparación definitiva de lesiones traumáticas, con el objetivo de la recuperación fisiológica deteriorada por lesiones y/o complicaciones que pueden poner en peligro la vida, realizando entonces procedimientos quirúrgicos sencillos, como una estabilización quirúrgica externa de las fracturas. Objetivo: determinar el comportamiento del control de daños ortopédicos en politraumatizados pediátricos. Materiales y método: se realizó un estudio observacional, descriptivo, prospectivo, de corte transversal, de enero del 2015 a diciembre del 2018. El universo estuvo constituido por 22 pacientes menores de 19 años de edad, politraumatizados en el período; la muestra por 15 pacientes, a los que se les aplicó control de daños ortopédicos, según criterios de selección. Resultados: se aplicó control de daños ortopédicos a 15 infantes. El más afectado fue el sexo masculino con el 73,3 %. Prevalecieron los traumatismos de los miembros inferiores con el 58,3 % y las fracturas cerradas con un 53,8 %. La osteomielitis crónica fue la complicación que predominó, en el 20 % de la muestra. En el 73,3 % de los casos se evaluó como satisfactoria la aplicación del control de daños ortopédicos en los politraumatizados. Conclusiones: a la totalidad de los traumatizados se le aplicó control de daños ortopédicos. Predominó el sexo masculino y el grupo de edad de 9 -14 años. Los miembros inferiores aportan la mayor cantidad con el fémur y la tibia. El control de daños ortopédicos se evaluó satisfactoriamente en la mayoría de los pacientes estudiados (AU).
ABSTRAC Introduction: the control of damages in Orthopedics is to postpone the definitive repair of traumatic lesions, with the objective of the physiologic recovery deteriorated by lesions and/or complications that can put in danger the life, carrying out simple surgical procedures, like an external surgical stabilization of the fractures at that time. . Objective: to determine the behavior of the orthopedic damage control in pediatric politraumatized patients. Material and method: a cross-sectional, prospective, descriptive, observational study was carried out from January 2015 to December 2018. The universe was formed by 22 patients younger than 19 years politraumatized in the period and the sample formed 15 patients; they underwent orthopedic damage control, according to the selection criteria. Results: the orthopedic damage control, was applied to 15 children. Male sex was the most affected one. Trauma in the lower limbs with 58.3 % and closed fractures with 53.8 prevailed. The predominating complication was chronic poliomyelitis in 20 % of the sample. The orthopedic damage control in politraumatized patients was assessed as successful in 73.3 % of the cases. Conclusions: the orthopedic damage control was applied to the total of traumatized patients. The male sex and the 9-14 years-old age group predominated. Lower limbs contributed with the biggest quantity of trauma, in femur and tibia. The orthopedic damage control was assessed as successful in most of studied patients (AU).