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Fusarium, a member of the Ascomycota fungi, encompasses several pathogenic species significant to plants and animals. Some phytopathogenic species have received special attention due to their negative economic impact on the agricultural industry around the world. Traditionally, identification and taxonomic analysis of Fusarium have relied on morphological and phenotypic features, including the fungal host, leading to taxonomic conflicts that have been solved using molecular systematic technologies. In this work, we applied a phylogenomic approach that allowed us to resolve the evolutionary history of the species complexes of the genus and present evidence that supports the F. ventricosum species complex as the most basal lineage of the genus. Additionally, we present evidence that proposes modifications to the previous hypothesis of the evolutionary history of the F. staphyleae, F. newnesense, F. nisikadoi, F. oxysporum, and F. fujikuroi species complexes. Evolutionary analysis showed that the genome GC content tends to be lower in more modern lineages, in both, the whole-genome and core-genome coding DNA sequences. In contrast, genome size gain and losses are present during the evolution of the genus. Interestingly, core genome duplication events positively correlate with genome size. Evolutionary and genome conservation analysis supports the F3 hypothesis of Fusarium as a more compact and conserved group in terms of genome conservation. By contrast, outside of the F3 hypothesis, the most basal clades only share 8.8% of its genomic sequences with the F3 clade.
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Fusarium , Fusarium/genética , Genoma Fúngico , Genómica , Tamaño del Genoma , Filogenia , Enfermedades de las Plantas/microbiologíaRESUMEN
OBJECTIVE: This study evaluates the ROX index's accuracy in predicting the success or failure of high-flow nasal cannula (HFNC) therapy in children under 2 years with acute respiratory failure (ARF) from lower respiratory tract infections. METHODS: From January 2018 to 2021 we conducted this multicenter retrospective cohort study, which included patients aged 2-24 months. We aimed to assess HFNC therapy outcomes as either success or failure. The analysis covered patient demographics, diagnoses, vital signs, and ROX index values at intervals from 0 to 48 h after initiating HFNC. We used bivariate analysis, repeated measures ANOVA, multivariate logistic regression, and the area under the receiver operating characteristic (AUC-ROC) curve for statistical analysis. RESULTS: The study involved 529 patients from six centers, with 198 females (37%) and a median age of 9 months (IQR: 3-15 months). HFNC therapy failed in 38% of cases. We observed significant variability in failure rates across different centers and physicians (p < .001). The ROX index was significantly associated with HFNC outcomes at all time points, showing an increasing trend in success cases over time (p < .001), but not in HFNC failure cases. Its predictive ability is limited, with AUC-ROC values ranging from 0.56 at the start to 0.67 at 48 h. CONCLUSION: While the ROX index is associated with HFNC outcomes in children under 2 years, its predictive ability is modest, impacted by significant variability among patients, physicians, and centers. These findings emphasize the need for more reliable predictive tools for HFNC therapy in this patient population.
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Cánula , Terapia por Inhalación de Oxígeno , Insuficiencia Respiratoria , Infecciones del Sistema Respiratorio , Insuficiencia del Tratamiento , Humanos , Femenino , Masculino , Lactante , Estudios Retrospectivos , Infecciones del Sistema Respiratorio/terapia , Terapia por Inhalación de Oxígeno/métodos , Terapia por Inhalación de Oxígeno/instrumentación , Insuficiencia Respiratoria/terapia , Saturación de Oxígeno , PreescolarRESUMEN
INTRODUCTION: For over a century, Sporothrix schenckii was considered the sole species responsible for sporotrichosis. In 2007, scientific community confirmed the disease could be caused by various Sporothrix species. These species differed in their virulence factors and their antifungal sensitivity. OBJECTIVE: This study aims to characterize 42 Colombian clinical isolates of Sporothrix spp. phenotypically and genotypically. MATERIAL AND METHODS: Forty-two clinical isolates were characterized using phenotypic methods. It involved various culture media to determine their growth range at different temperatures and to assess the type and distribution of pigment and colony texture. Microscopic morphology was evaluated through microcultures, as well as the conidia diameter, type of sporulation, and morphology. Additionally, the assimilation of carbohydrates was selected as a physiological trait for species identification. Genotyping of 40 isolates was performed through partial amplification of the calmodulin gene, followed by sequence analysis. RESULTS: Molecular studies enabled the identification of 32 isolates of S. schenckii and 8 isolates of S. globosa. The combination of phenotypic and genotypic methods eased these species characterizations and the recognition keys development based on parameters such as growth diameter at 25 and 30 ºC, colony texture (membranous or velvety) on potato dextrose agar, and microscopic morphology with predominance of pigmented triangular, elongated oval globose, or subglobose conidia. CONCLUSIONS: Confirmation of the phenotypic characteristics and molecular analysis is crucial for identifying Sporothrix species and determining adequate treatment. This study represents the first phenotypical and genotypical characterization of clinical isolates of Sporothrix spp. reported in Colombia.
Introducción: Por más de un siglo se creyó que Sporothrix schenckii era la única especie responsable de la esporotricosis. Sin embargo, en el 2007, se consideró que podría ser causada por diferentes especies de Sporothrix, que difieren en sus factores de virulencia y su sensibilidad a los antifúngicos. Objetivo: Caracterizar fenotípica y genotípicamente 42 aislamientos clínicos colombianos de Sporothrix spp. Materiales y métodos: Se caracterizaron 42 aislamientos clínicos mediante métodos fenotípicos. Se usaron varios medios de cultivo para determinar el rango de crecimiento a diferentes temperaturas, el tipo y la distribución del pigmento, y la textura de las colonias. Se evaluó la morfología microscópica por microcultivos mediante la determinación del diámetro, el tipo de esporulación y la morfología de las conidias. La asimilación de carbohidratos se usó como una característica fisiológica para identificar las especies. La genotipificación de los 40 aislamientos se llevó a cabo mediante la amplificación parcial del gen que codifica para la calmodulina y se confirmó por secuenciación. Resultados: Mediante estudios moleculares, se identificaron 32 aislamientos de S. schenckii y ocho de S. globosa. La combinación de métodos fenotípicos y genotípicos permitió caracterizar las especies y construir claves para su reconocimiento, con base en parámetros como el diámetro de crecimiento a 25 y 30 ºC, la textura de las colonias (membranosa, aterciopelada) en agar papa dextrosa y la morfología microscópica con predominio de conidias (triangulares pigmentadas, ovales globosas elongadas, subglobosas). Conclusiones: La caracterización fenotípica y los análisis moleculares son necesarios para identificar las especies de Sporothrix y, de esta forma, elegir el tratamiento indicado. Esta es la primera caracterización fenotípica y genotípica reportada de aislamientos clínicos colombianos de Sporothrix spp.
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Sporothrix , Colombia , Sporothrix/genética , Genotipo , Fenotipo , Antifúngicos , Medios de CultivoRESUMEN
Objetivos: Incidencia del síndrome post-cuidados intensivos al mes del alta hospitalaria en pacientes críticos supervivientes de COVID-19 e identificar factores asociados. Diseño: Estudio de cohortes prospectivo. Ámbito: Dos unidades de críticos polivalentes del Hospital Universitario Araba. Pacientes ingresados en unidades de críticos por insuficiencia respiratoria aguda grave secundaria a COVID-19. Intervención: Ninguna. Variables de interés: Variables demográficas, estancias, índice de Charlson, APACHEII, SOFA, días de ventilación mecánica, traqueotomía, delirio, tetraparesia del paciente crítico, EuroQol 5D5L, Minimental Test. Resultados: Se objetiva un deterioro en el índice de salud (IS) del EuroQol, que pasa de 90,9 ±16,9 a 70,9 ±24,7 (p<0,001). La afectación de los cinco dominios del EuroQol es de: movilidad (46,1%), actividades habituales (44,7%), malestar/dolor (30,7%), dominio psicológico (27,3%) y autocuidado (20,3%). El 61,5% sufren un descenso significativo de su índice de salud. El análisis multivariante mediante regresión logística nos muestra que el delirio (OR=3,01; IC95%: 1,01-8,9; p=0,047) y la traqueotomía (OR=2,37; IC95%: 1,09-5,14; p=0,029) muestran asociación con la caída en el IS del EuroQol 5D5L. El área bajo la curva ROC del modelo es del 67,3%, con un intervalo de confianza entre el 58% y el 76%. Se calibra el modelo mediante el test de Hosmer-Lemeshow:(χ2=0,468; p=0,792). Solamente el 1,2% de los pacientes mostraban una puntuación ≤24, claramente patológica, en el Minimental Test de Folstein. Conclusiones: El delirio y la necesidad de traqueostomía se asocian a síndrome post-cuidados intensivos evaluado mediante EuroQol 5D5L. (AU)
Objectives: Incidence of post-intensive care syndrome at one month after hospital discharge in surviving critically ill COVID-19 patients and to identify associated factors. Design: Prospective cohort study. Setting: Two multipurpose critical care units of the Araba University Hospital. Patients admitted to critical care units for severe acute respiratory failure secondary to COVID-19. Intervention: None. Variables of interest: Demographic variables, length of stay, Charlson index, APACHEII, SOFA, days of mechanical ventilation, tracheotomy, delirium, tetraparesis of the critical patient, EuroQol 5D5L, Minimental Test. Results: A deterioration in the EuroQol health index (HI) from 90.9 ±16.9 to 70.9 ±24.7 (P<.001) was observed. The impairment of the five EuroQol domains is: mobility (46.1%), usual activities (44.7%), discomfort/pain (30.7%), psychological domain (27.3%) and self-care (20.3%). The 61.5% suffer a significant decrease in their health index. Multivariate analysis by logistic regression shows us that delirium (OR=3.01; 95%CI: 1.01-8.9; P=.047) and tracheostomy (OR=2.37; 95%CI: 1.09-5.14; P=.029) show association with drop in EuroQol 5D5L SI. The area under the ROC curve of the model is 67.3%, with a confidence interval between 58% and 76%. The model is calibrated using the Hosmer-Lemeshow test (χ2=0.468; P=.792). Only 1.2% of patients showed a score ≤24, clearly pathological, on the Folstein's Minimental Test. Conclusions: Delirium and need for tracheostomy are associated with post-intensive care syndrome assessed by EuroQol 5D5L. (AU)
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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Pandemias , Infecciones por Coronavirus/epidemiología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Enfermedad Crítica , Estudios Prospectivos , Estudios de Cohortes , Calidad de VidaRESUMEN
The ability to make inferences based on statistical information has so far been tested only in animals having large brains in relation to their body size, like primates and parrots. Here we tested if giraffes (Giraffa camelopardalis), despite having a smaller relative brain size, can rely on relative frequencies to predict sampling outcomes. We presented them with two transparent containers filled with different quantities of highly-liked food and less-preferred food. The experimenter covertly drew one piece of food from each container, and let the giraffe choose between the two options. In the first task, we varied the quantity and relative frequency of highly-liked and less-preferred food pieces. In the second task, we inserted a physical barrier in both containers, so giraffes only had to take into account the upper part of the container when predicting the outcome. In both tasks giraffes successfully selected the container more likely to provide the highly-liked food, integrating physical information to correctly predict sampling information. By ruling out alternative explanations based on simpler quantity heuristics and learning processes, we showed that giraffes can make decisions based on statistical inferences.
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Jirafas , Animales , Alimentos , AprendizajeRESUMEN
Strains of Xanthomonas citri pv. malvacearum cause bacterial blight of cotton, a potentially serious threat to cotton production worldwide, including in sub-Saharan countries. Development of disease symptoms, such as water soaking, has been linked to the activity of a class of type 3 effectors, called transcription activator-like (TAL) effectors, which induce susceptibility genes in the host's cells. To gain further insight into the global diversity of the pathogen, to elucidate their repertoires of TAL effector genes, and to better understand the evolution of these genes in the cotton-pathogenic xanthomonads, we sequenced the genomes of three African strains of X. citri pv. malvacearum using nanopore technology. We show that the cotton-pathogenic pathovar of X. citri is a monophyletic lineage containing at least three distinct genetic subclades, which appear to be mirrored by their repertoires of TAL effectors. We observed an atypical level of TAL effector gene pseudogenization, which might be related to resistance genes that are deployed to control the disease. Our work thus contributes to a better understanding of the conservation and importance of TAL effectors in the interaction with the host plant, which can inform strategies for improving resistance against bacterial blight in cotton.
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Innovation is the ability to solve new problems or find novel solutions to familiar problems, and it is known to provide animals with crucial fitness benefits. Although this ability has been extensively studied in some taxa, the factors that predict innovation within and across species are still largely unclear. In this study, we used a novel foraging task to test 111 individuals belonging to 13 ungulate species-a still understudied taxon. To solve the task, individuals had to open transparent and opaque cups with food rewards, by removing their cover. We assessed whether individual factors (neophobia, social integration, sex, age, rank) and socio-ecological factors (dietary breadth, fission-fusion dynamics, domestication, group size) predicted participation and performance in the task. Using a phylogenetic approach, we showed that success was higher for less neophobic and socially less integrated individuals. Moreover, less neophobic individuals, individuals of domesticated species and having higher fission-fusion dynamics were more likely to participate in the task. These results are in line with recent literature suggesting a central role of sociality and personality traits to successfully deal with novel challenges, and confirm ungulates as a promising taxon to test evolutionary theories with a comparative approach.
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Creatividad , Grupo Social , Animales , Filogenia , Conducta Social , MamíferosRESUMEN
In this work, the characterization and analysis of the physics of a GaAs quantum well with AlGaAs barriers were carried out, according to an interior doped layer. An analysis of the probability density, the energy spectrum, and the electronic density was performed using the self-consistent method to solve the Schrödinger, Poisson, and charge-neutrality equations. Based on the characterizations, the system response to geometric changes in the well width and to non-geometric changes, such as the position and with of the doped layer as well as the donor density, were reviewed. All second-order differential equations were solved using the finite difference method. Finally, with the obtained wave functions and energies, the optical absorption coefficient and the electromagnetically induced transparency between the first three confined states were calculated. The results showed the possibility of tuning the optical absorption coefficient and the electromagnetically induced transparency via changes to the system geometry and the doped-layer characteristics.
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The cotton boll weevil (CBW) (Anthonomus grandis) is one of the major insect pests of cotton in Brazil. Currently, CBW control is mainly achieved by insecticide application, which is costly and insufficient to ensure effective crop protection. RNA interference (RNAi) has been used in gene function analysis and the development of insect control methods. However, some insect species respond poorly to RNAi, limiting the widespread application of this approach. Therefore, nanoparticles have been explored as an option to increase RNAi efficiency in recalcitrant insects. Herein, we investigated the potential of chitosan-tripolyphosphate (CS-TPP) and polyethylenimine (PEI) nanoparticles as a dsRNA carrier system to improve RNAi efficiency in the CBW. Different formulations of the nanoparticles with dsRNAs targeting genes associated with juvenile hormone metabolism, such as juvenile hormone diol kinase (JHDK), juvenile hormone epoxide hydrolase (JHEH), and methyl farnesoate hydrolase (MFE), were tested. The formulations were delivered to CBW larvae through injection (0.05-2 µg), and the expression of the target genes was evaluated using RT-qPCR. PEI nanoparticles increased targeted gene silencing compared with naked dsRNAs (up to 80%), whereas CS-TPP-dsRNA nanoparticles decreased gene silencing (0%-20%) or led to the same level of gene silencing as the naked dsRNAs (up to 50%). We next evaluated the effects of targeting a single gene or simultaneously targeting two genes via the injection of naked dsRNAs or dsRNAs complexed with PEI (500 ng) on CBW survival and phenotypes. Overall, the gene expression analysis showed that the treatments with PEI targeting either a single gene or multiple genes induced greater gene silencing than naked dsRNA (â¼60%). In addition, the injection of dsJHEH/JHDK, either naked or complexed with PEI, significantly affected CBW survival (18% for PEI nanoparticles and 47% for naked dsRNA) and metamorphosis. Phenotypic alterations, such as uncompleted pupation or malformed pupae, suggested that JHEH and JHDK are involved in developmental regulation. Moreover, CBW larvae treated with dsJHEH/JHDK + PEI (1,000 ng/g) exhibited significantly lower survival rate (55%) than those that were fed the same combination of naked dsRNAs (30%). Our findings demonstrated that PEI nanoparticles can be used as an effective tool for evaluating the biological role of target genes in the CBW as they increase the RNAi response.
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Deficits in arousal and stress responsiveness are a feature of numerous psychiatric disorders including depression and anxiety. Arousal is supported by norepinephrine (NE) released from specialized brainstem nuclei, including the locus coeruleus (LC) neurons into cortical and limbic areas. During development, the NE system matures in concert with increased exploration of the animal's environment. While several psychiatric medications target the NE system, the possibility that its modulation during discreet developmental periods can have long-lasting consequences has not yet been explored. We used a chemogenetic strategy in mice to reversibly inhibit NE signaling during brief developmental periods and then evaluated any long-lasting impact of our intervention on adult NE circuit function and on emotional behavior. We also tested whether developmental exposure to the α2 receptor agonist guanfacine, which is commonly used in the pediatric population and is not contraindicated during pregnancy and nursing, recapitulates the effect seen with the chemogenetic strategy. Our results reveal that postnatal days 10-21 constitute a sensitive period during which alterations in NE signaling lead to changes in baseline anxiety, increased anhedonia, and passive coping behaviors in adulthood. Disruption of NE signaling during this sensitive period also caused altered LC autoreceptor function, along with circuit specific changes in LC-NE target regions at baseline, and in response to stress. Our findings indicate an early critical role for NE in sculpting brain circuits that support adult emotional function. Interfering with this role by guanfacine and similar clinically used drugs can have lasting implications for mental health.
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Locus Coeruleus , Norepinefrina , Niño , Ratones , Humanos , Animales , Norepinefrina/farmacología , Locus Coeruleus/fisiología , Guanfacina/farmacología , Neuronas/fisiología , AnsiedadRESUMEN
OBJECTIVES: Incidence of post-intensive care syndrome at one month after hospital discharge in surviving critically ill COVID 19 patients and to identify associated factors. DESIGN: Prospective cohort study. SETTING: Two multipurpose critical care units of the Araba University Hospital. Patients admitted to critical care units for severe acute respiratory failure secondary to COVID 19. INTERVENTION: None. VARIABLES OF INTEREST: Demographic variables, length of stay, Charlson index, APACHE II, SOFA, days of mechanical ventilation, tracheotomy, delirium, tetraparesis of the critical patient, EuroQol 5D5L, Minimental Test. RESULTS: A deterioration in the EuroQol health index (HI) from 90.9±16.9 to 70.9±24.7 (p<0.001) was observed. The impairment of the five EuroQol domains is: mobility (46.1%), usual activities (44.7%), discomfort/pain (30.7%), psychological domain (27.3%) and self-care (20.3%). The 61.5% suffer a significant decrease in their health index. Multivariate analysis by logistic regression shows us that delirium (OR=3.01; 95%CI: 1.01-8.9; p=0.047) and tracheostomy (OR=2.37; 95%CI: 1.09-5.14; p=0.029) show association with drop in EuroQoL 5D5L SI. The area under the ROC curve of the model is 67.3%, with a confidence interval between 58% and 76%. The model is calibrated using the Hosmer-Lemeshow test (χ2=0.468; p=0.792). Only 1.2% of patients showed a score ≤ 24, clearly pathological, on the Folstein's Minimental Test. CONCLUSIONS: Delirium and need for tracheostomy are associated with post-intensive care syndrome assessed by EuroQol 5D5L.
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COVID-19 , Delirio , Humanos , Enfermedad Crítica , Estudios Prospectivos , Alta del Paciente , Factores de Riesgo , COVID-19/complicaciones , Delirio/epidemiología , Delirio/etiologíaRESUMEN
Contemporary diets in Western countries are largely acid-inducing and deficient in potassium alkali salts, resulting in low-grade metabolic acidosis. The chronic consumption of acidogenic diets abundant in animal-based foods (meats, dairy, cheese and eggs) poses a substantial challenge to the human body's buffering capacities and chronic retention of acid wherein the progressive loss of bicarbonate stores can cause cellular and tissue damage. An elevated dietary acid load (DAL) has been associated with systemic inflammation and other adverse metabolic conditions. In this narrative review, we examine DAL quantification methods and index observational and clinical evidence on the role of plant-based diets, chiefly vegetarian and vegan, in reducing DAL. Quantitation of protein and amino acid composition and of intake of alkalising organic potassium salts and magnesium show that plant-based diets are most effective at reducing DAL. Results from clinical studies and recommendations in the form of expert committee opinions suggest that for a number of common illnesses, wherein metabolic acidosis is a contributing factor, the regular inclusion of plant-based foods offers measurable benefits for disease prevention and management. Based on available evidence, dietary shifts toward plant-based nutrition effectively reduces dietary-induced, low-grade metabolic acidosis.
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Acidosis , Dieta Vegetariana , Humanos , Sales (Química) , Dieta , Acidosis/prevención & control , PotasioRESUMEN
OBJECTIVES: incidence of post-intensive care syndrome at one month after hospital discharge in surviving critically ill COVID 19 patients and to identify associated factors. DESIGN: prospective cohort study. SETTING: two multipurpose critical care units of the Araba University Hospital.Patients admitted to critical care units for severe acute respiratory failure secondary to COVID 19. INTERVENTION: none. VARIABLES OF INTEREST: demographic variables, length of stay, Charlson index, APACHE II, SOFA, days of mechanical ventilation, tracheotomy, delirium, tetraparesis of the critical patient, EuroQol 5D5L, Minimental Test. RESULTS: a deterioration in the EuroQol health index (HI) from 90.9 ± 16.9 to 70.9 ± 24.7 (p < 0.001) was observed. The impairment of the five EuroQol domains is: mobility (46.1%), usual activities (44.7%), discomfort/pain (30.7%), psychological domain (27.3%) and self-care (20.3%). The 61.5% suffer a significant decrease in their health index. Multivariate analysis by logistic regression shows us that delirium (OR= 3.01; 95%CI: 1.01-8.9; p= 0.047) and tracheostomy (OR= 2.37; 95%CI: 1.09-5.14; p= 0.029) show association with drop in EuroQoL 5D5L SI. The area under the ROC curve of the model is 67.3%, with a confidence interval between 58% and 76%. The model is calibrated using the Hosmer-Lemeshow test:(χ2=0.468; p=0.792). Only 1.2% of patients showed a score ≤ 24, clearly pathological, on the Folstein's Minimental Test. CONCLUSIONS: delirium and need for tracheostomy are associated with post-intensive care syndrome assessed by EuroQol 5D5L.
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The outbreak of COVID-19, beginning in 2019 and continuing through the time of writing, has led to renewed interest in the mathematical modeling of infectious disease. Recent works have focused on partial differential equation (PDE) models, particularly reaction-diffusion models, able to describe the progression of an epidemic in both space and time. These studies have shown generally promising results in describing and predicting COVID-19 progression. However, people often travel long distances in short periods of time, leading to nonlocal transmission of the disease. Such contagion dynamics are not well-represented by diffusion alone. In contrast, ordinary differential equation (ODE) models may easily account for this behavior by considering disparate regions as nodes in a network, with the edges defining nonlocal transmission. In this work, we attempt to combine these modeling paradigms via the introduction of a network structure within a reaction-diffusion PDE system. This is achieved through the definition of a population-transfer operator, which couples disjoint and potentially distant geographic regions, facilitating nonlocal population movement between them. We provide analytical results demonstrating that this operator does not disrupt the physical consistency or mathematical well-posedness of the system, and verify these results through numerical experiments. We then use this technique to simulate the COVID-19 epidemic in the Brazilian region of Rio de Janeiro, showcasing its ability to capture important nonlocal behaviors, while maintaining the advantages of a reaction-diffusion model for describing local dynamics.
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The computer simulation of organ-scale biomechanistic models of cancer personalized via routinely collected clinical and imaging data enables to obtain patient-specific predictions of tumor growth and treatment response over the anatomy of the patient's affected organ. These patient-specific computational forecasts have been regarded as a promising approach to personalize the clinical management of cancer and derive optimal treatment plans for individual patients, which constitute timely and critical needs in clinical oncology. However, the computer simulation of the underlying spatiotemporal models can entail a prohibitive computational cost, which constitutes a barrier to the successful development of clinically-actionable computational technologies for personalized tumor forecasting. To address this issue, here we propose to utilize dynamic-mode decomposition (DMD) to construct a low-dimensional representation of cancer models and accelerate their simulation. DMD is an unsupervised machine learning method based on the singular value decomposition that has proven useful in many applications as both a predictive and a diagnostic tool. We show that DMD may be applied to Fisher-Kolmogorov models, which constitute an established formulation to represent untreated solid tumor growth that can further accommodate other relevant cancer phenomena (e.g., therapeutic effects, mechanical deformation). Our results show that a DMD implementation of this model over a clinically relevant parameter space can yield promising predictions, with short to medium-term errors remaining under 1% and long-term errors remaining under 20%, despite very short training periods. In particular, we have found that, for moderate to high tumor cell diffusivity and low to moderate tumor cell proliferation rate, DMD reconstructions provide accurate, bounded-error reconstructions for all tested training periods. Additionally, we also show that the three-dimensional DMD reconstruction of the tumor field can be leveraged to accurately reconstruct the displacement fields of the tumor-induced deformation of the host tissue. Thus, we posit the proposed data-driven approach has the potential to greatly reduce the computational overhead of personalized simulations of cancer models, thereby facilitating tumor forecasting, parameter identification, uncertainty quantification, and treatment optimization.
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Neoplasias , Simulación por Computador , HumanosRESUMEN
In this work, a finite periodic superlattice is studied, analyzing the probability of electronic transmission for two types of semiconductor heterostructures, GaAs/AlGaAs and InSe/InP. The changes in the maxima of the quasistationary states for both materials are discussed, making variations in the number of periods of the superlattice and its shape by means of geometric parameters. The effect of a non-resonant intense laser field has been included in the system to analyze the changes in the electronic transport properties by means of the Landauer formalism. It is found that the highest tunneling current is given for the GaAs-based compared to the InSe-based system and that the intense laser field improves the current-voltage characteristics generating higher current peaks, maintaining a negative differential resistance (NDR) effect, both with and without laser field for both materials and this fact allows to tune the magnitude of the current peak with the external field and therefore extend the range of operation for multiple applications. Finally, the power of the system is discussed for different bias voltages as a function of the chemical potential.
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Arsenicales , Galio , Arsenicales/química , Electrónica , Galio/química , Rayos LáserRESUMEN
Resonant tunneling devices are still under study today due to their multiple applications in optoelectronics or logic circuits. In this work, we review an out-of-equilibrium GaAs/AlGaAs double-barrier resonant tunneling diode system, including the effect of donor density and external potentials in a self-consistent way. The calculation method uses the finite-element approach and the Landauer formalism. Quasi-stationary states, transmission probability, current density, cut-off frequency, and conductance are discussed considering variations in the donor density and the width of the central well. For all arrangements, the appearance of negative differential resistance (NDR) is evident, which is a fundamental characteristic of practical applications in devices. Finally, a comparison of the simulation with an experimental double-barrier system based on InGaAs with AlAs barriers reported in the literature has been obtained, evidencing the position and magnitude of the resonance peak in the current correctly.
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Carajurin is the main constituent of Arrabidaea chica species with reported anti-Leishmania activity. However, its mechanism of action has not been described. This study investigated the mechanisms of action of carajurin against promastigote forms of Leishmania amazonensis. Carajurin was effective against promastigotes with IC50 of 7.96 ± 1.23 µg.mL-1 (26.4 µM), and the cytotoxic concentration for peritoneal macrophages was 258.2 ± 1.20 µg.mL-1 (856.9 µM) after 24 h of treatment. Ultrastructural evaluation highlighted pronounced swelling of the kinetoplast with loss of electron-density in L. amazonensis promastigotes induced by carajurin treatment. It was observed that carajurin leads to a decrease in the mitochondrial membrane potential (p = 0.0286), an increase in reactive oxygen species production (p = 0.0286), and cell death by late apoptosis (p = 0.0095) in parasites. Pretreatment with the antioxidant NAC prevented ROS production and significantly reduced carajurin-induced cell death. The electrochemical and density functional theory (DFT) data contributed to support the molecular mechanism of action of carajurin associated with the ROS generation, for which it is possible to observe a correlation between the LUMO energy and the electroactivity of carajurin in the presence of molecular oxygen. All these results suggest that carajurin targets the mitochondria in L. amazonensis. In addition, when assessed for its drug-likeness, carajurin follows Lipinski''s rule of five, and the Ghose, Veber, Egan, and Muegge criteria.
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Dynamic mode decomposition (DMD) is a powerful data-driven method used to extract spatio-temporal coherent structures that dictate a given dynamical system. The method consists of stacking collected temporal snapshots into a matrix and mapping the nonlinear dynamics using a linear operator. The classical procedure considers that snapshots possess the same dimensionality for all the observable data. However, this often does not occur in numerical simulations with adaptive mesh refinement/coarsening schemes (AMR/C). This paper proposes a strategy to enable DMD to extract features from observations with different mesh topologies and dimensions, such as those found in AMR/C simulations. For this purpose, the adaptive snapshots are projected onto the same reference function space, enabling the use of snapshot-based methods such as DMD. The present strategy is applied to challenging AMR/C simulations: a continuous diffusion-reaction epidemiological model for COVID-19, a density-driven gravity current simulation, and a bubble rising problem. We also evaluate the DMD efficiency to reconstruct the dynamics and some relevant quantities of interest. In particular, for the SEIRD model and the bubble rising problem, we evaluate DMD's ability to extrapolate in time (short-time future estimates).