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1.
Bioresour Technol ; 406: 130961, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38876281

RESUMEN

This study investigates the potential of humic substances (HS) and graphene oxide (GO), as extracellular electron acceptors (EEA) for nitrification, aiming to explore alternatives to sustain this process in wastewater treatment systems. Experimental results demonstrate the conversion of ammonium to nitrate (up to 87 % of conversion) coupled to the reduction of either HS or GO by anaerobic consortia. Electron balance confirmed the contribution of HS and GO to ammonium oxidation. Tracer analysis in incubations performed with 15NH4+ demonstrated 15NO3- as the main product with a minor fraction ending as 29N2. Phylogenetic analysis identified Firmicutes, Euryarchaeota, and Chloroflexi as the microbial lineages potentially involved in anoxic nitrification linked to HS reduction. This study introduces a new avenue for research in which carbon-based materials with electron-accepting capacity may support the anoxic oxidation of ammonium, for instance in bioelectrochemical systems in which carbon-based anodes could support this novel process.


Asunto(s)
Carbono , Nitrificación , Carbono/química , Electrones , Grafito/química , Filogenia , Oxidación-Reducción , Compuestos de Amonio/metabolismo , Anaerobiosis , Nitratos/metabolismo , Bacterias/metabolismo
2.
Sci Total Environ ; 923: 171368, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38438040

RESUMEN

Coastal sediments play a central role in regulating the amount of land-derived reactive nitrogen (Nr) entering the ocean, and their importance becomes crucial in vulnerable ecosystems threatened by anthropogenic activities. Sedimentary denitrification has been identified as the main sink of Nr in marine environments, while anaerobic ammonium oxidation with nitrite (anammox) has also been pointed out as a key player in controlling the nitrogen pool in these locations. Collected evidence in the present work indicates that the microbial biota in coastal sediments from Baja California (northwestern Mexico) has the potential to drive anaerobic ammonium oxidation linked to Mn(IV) reduction (manganammox). Unamended sediment showed ammonification, but addition of vernadite (δMnO2 with nano-crystal size ∼15 Å) as terminal electron acceptor fueled simultaneous ammonium oxidation (up to ∼400 µM of ammonium removed) and production of Mn(II) with a ratio ∆[Mn(II)]/∆[NH4+] of 1.8, which is very close to the stoichiometric value of manganammox (1.5). Additional incubations spiked with external ammonium also showed concomitant ammonium oxidation and Mn(II) production, accounting for ∼30 % of the oxidized ammonium. Tracer analysis revealed that the nitrogen loss associated with manganammox was 4.2 ± 0.4 µg 30N2/g-day, which is 17-fold higher than that related to the feammox process (anaerobic ammonium oxidation linked to Fe(III) reduction, 0.24 ± 0.02 µg 30N2/g-day). Taxonomic characterization based on 16S rRNA gene sequencing revealed the existence of several clades belonging to Desulfobacterota as potential microorganisms catalyzing the manganammox process. These findings suggest that manganammox has the potential to be an additional Nr sink in coastal environments, whose contribution to total Nr losses remains to be evaluated.


Asunto(s)
Compuestos de Amonio , Nitrógeno , Nitrógeno/análisis , Anaerobiosis , Sedimentos Geológicos/química , Compuestos Férricos , Ecosistema , ARN Ribosómico 16S/genética , México , Óxidos , Oxidación-Reducción , Desnitrificación
3.
Brain Sci ; 14(1)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38248268

RESUMEN

(1) Background: Spinocerebellar ataxias (SCA) is a term that refers to a group of hereditary ataxias, which are neurological diseases characterized by degeneration of the cells that constitute the cerebellum. Studies suggest that magnetic resonance imaging (MRI) supports diagnoses of ataxias, and linear measurements of the aneteroposterior diameter of the midbrain (ADM) have been investigated using MRI. These measurements correspond to studies in spinocerebellar ataxia type 2 (SCA2) patients and in healthy subjects. Our goal was to obtain the cut-off value for ADM atrophy in SCA2 patients. (2) Methods: This study evaluated 99 participants (66 SCA2 patients and 33 healthy controls). The sample was divided into estimations (80%) and validation (20%) samples. Using the estimation sample, we fitted a logistic model using the ADM and obtained the cut-off value through the inverse of regression. (3) Results: The optimal cut-off value of ADM was found to be 18.21 mm. The area under the curve (AUC) of the atrophy risk score was 0.957 (95% CI: 0.895-0.991). Using this cut-off on the validation sample, we found a sensitivity of 100.00% (95% CI: 76.84%-100.00%) and a specificity of 85.71% (95% CI: 42.13%-99.64%). (4) Conclusions: We obtained a cut-off value that has an excellent discriminatory capacity to identify SCA2 patients.

4.
Phys Chem Chem Phys ; 26(3): 2260-2268, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38165403

RESUMEN

In this study, we investigated the mechanical behavior of pristine copper (Cu) nanoparticles (NPs) and Cu@graphene (Cu@G) hybrid NPs using molecular dynamics simulations. The longitudinal engineering strain was calculated as a measure of compression until reaching 25% of the initial size of the NPs. The stress-strain curves revealed the elastic-to-plastic transition in the Cu NPs at a longitudinal strain of 3.57% with a yield strength of 6.15 GPa. On the other hand, the Cu@G NPs exhibited a maximum average load point at a longitudinal strain of 6.81% with a yield strength of 8.26 GPa. The hybrid Cu@G NPs showed increased strength and resistance to plastic deformation compared to the pure Cu NPs, while the calculation of the elastic modulus indicated a higher load resistance provided by the graphene coverage for the Cu@G NPs. Furthermore, the analysis of atomic configurations, dislocations, and stress distribution demonstrated that the graphene flakes play a crucial role in preventing dislocation events and faceting in the Cu@G NPs by acting as a shock absorber, distributing the applied force on themselves, and producing a more homogeneous stress distribution on the Cu NPs; additionally, they prevent the movement of Cu atoms, reducing the occurrence of dislocations and surface faceting, thanks to their supportive effect. Overall, our findings highlight the potential of hybrid nanomaterials, such as Cu@G, for enhancing the mechanical properties of metallic NPs, which could have significant implications for the development of advanced nanomaterials with improved performance in a variety of applications.

5.
Biodegradation ; 35(1): 47-70, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37436663

RESUMEN

In the context of the anaerobic ammonium oxidation process (anammox), great scientific advances have been made over the past two decades, making anammox a consolidated technology widely used worldwide for nitrogen removal from wastewaters. This review provides a detailed and comprehensive description of the anammox process, the microorganisms involved and their metabolism. In addition, recent research on the application of the anammox process with alternative electron acceptors is described, highlighting the biochemical reactions involved, its advantages and potential applications for specific wastewaters. An updated description is also given of studies reporting the ability of microorganisms to couple the anammox process to extracellular electron transfer to insoluble electron acceptors; particularly iron, carbon-based materials and electrodes in bioelectrochemical systems (BES). The latter, also referred to as anodic anammox, is a promising strategy to combine the ammonium removal from wastewater with bioelectricity production, which is discussed here in terms of its efficiency, economic feasibility, and energetic aspects. Therefore, the information provided in this review is relevant for future applications.


Asunto(s)
Compuestos de Amonio , Aguas Residuales , Desnitrificación , Nitrógeno/metabolismo , Oxidación Anaeróbica del Amoníaco , Electrones , Oxidación-Reducción , Anaerobiosis , Reactores Biológicos , Compuestos de Amonio/metabolismo , Oxidantes
6.
Electrophoresis ; 45(3-4): 300-309, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37946567

RESUMEN

This paper analyzes the role of the diffusion coefficient in the movement of analytes that can reversibly react with a selector given a product in the presence of drift. The problem mimics the movement of enantiomers in a capillary electrophoresis experiment. As is well known, the signal in the capillary must be sharp enough to make a good determination of the effective mobility of the analytes being analyzed. The essence of the technique is based on fast interconversion rates. Therefore, the effective diffusion coefficient must be negligible during the experiment. In the present work, an exact expression for both the apparent mobility and the diffusion coefficient is obtained. This is done by writing the rate equations governing the process and solving them using the generating function technique. The effective mobility coincides with the Wren and Rowe equation, whereas the diffusion coefficient allows us to determine the values of the parameters to be taken into account so that this quantity is minimal or close to zero. On the other hand, the numerical solution of the kinetic equations and Monte Carlo simulations allow us to follow the signal in the capillary and to determine its space-time evolution.


Asunto(s)
Electroforesis Capilar , Electroforesis Capilar/métodos , Estereoisomerismo , Cinética , Método de Montecarlo , Difusión
7.
J Clin Med ; 12(19)2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37834850

RESUMEN

Asthma is a widespread disease affecting approximately 300-million people globally. This condition leads to significant morbidity, mortality, and economic strain worldwide. Recent clinical and laboratory research advancements have illuminated the immunological factors contributing to asthma. As of now, asthma is understood to be a heterogeneous disease. Personalized medicine involves categorizing asthma by its endotypes, linking observable characteristics to specific immunological mechanisms. Identifying these endotypic mechanisms is paramount in accurately profiling patients and tailoring therapeutic approaches using innovative biological agents targeting distinct immune pathways. This article presents a synopsis of the key immunological mechanisms implicated in the pathogenesis and manifestation of the disease's phenotypic traits and individualized treatments for severe asthma subtypes.

9.
MHSalud ; 20(1): 127-139, Jan.-Jun. 2023. tab
Artículo en Español | LILACS, SaludCR | ID: biblio-1558367

RESUMEN

Resumen: Introducción: el conocimiento de los entrenamientos es fundamental para optimizar la formación de los jugadores; por ello, una de las estrategias más empleadas por los entrenadores para optimizar el proceso de entrenamiento es modificar el número de jugadores (Situación de Juego). Objetivo: el objetivo del estudio fue analizar el proceso de enseñanza-aprendizaje de un entrenador de baloncesto en edad escolar, así como conocer la asociación de la Situación de Juego y las variables pedagógicas, de carga externa y organizativa empleadas que influyen en el diseño de las tareas. Método: para ello, se analizaron un total de 20 sesiones de entrenamiento formadas por 100 tareas, registradas a través del Sistema integral para el análisis de las tareas de entrenamiento. Se realizó un análisis descriptivo e inferencial entre las variables planteadas en la investigación con relación a la Situación de Juego. Resultados: los resultados demostraron la relación significativa de las variables analizadas con la Situación de Juego. La forma de agrupar los jugadores durante el desarrollo de las tareas de entrenamiento condiciona los resultados del resto de las variables que definen una tarea de entrenamiento, tanto en el nivel pedagógico, organizativo, como de carga externa. Conclusión: estas evidencias revindican la importancia de conocer los factores que influyen en las tareas de entrenamiento. Además, los resultados muestran que existen diferencias en el empleo de las Situaciones de Juego en función del resto de variables empleadas.


Abstract: Introduction: Currently, Knowledge of training is essential to optimize player training. Therefore, one of the strategies most used by coaches to optimize the training process is to modify the number of players (Game Situation). Purpose: The objective of the study was to analyze the teaching-learning process of a school-age basketball coach, as well as to know the association of the Game Situation and the Pedagogical, External Load and Organizational variables used that influence the design of the tasks. Method: For this, a total of 20 training sessions consisting of 100 tasks, recorded through the Comprehensive System for the Analysis of Training Tasks, were analyzed. A descriptive and inferential analysis was carried out between the variables raised in the research in relation to the Game Situation. Results: The results demonstrated the significant relationship of the variables analyzed with the Game Situation. The way the players are grouped during the development of the training tasks conditions the results of the rest of the variables that define a training task, both at a pedagogical, organizational, and external load level. Conclusion: These evidences vindicate the importance of knowing the factors that influence training tasks. In addition, the results show that there are differences in the use of Game Situations depending on the rest of the variables used.


Resumo: Introdução: O conhecimento do treinamento é fundamental para otimizar o processo de formação dos jogadores. Portanto, uma das estratégias mais utilizadas pelos treinadores para otimizar o processo de treinamento é modificar o número de jogadores (Situação do jogo). Objetivo: O objetivo do estudo foi analisar o processo de ensino-aprendizagem de um treinador de basquetebol em idade escolar, e também descobrir a associação entre a Situação do Jogo e as variáveis Pedagógicas, de Carga Externa e Organizacionais utilizadas que influenciam o desenho das tarefas. Método: Para este fim, foram analisadas 20 sessões de treinamento compostas de 100 tarefas, registradas através do Sistema Integral de Análise de Tarefas de Treinamento. Foi realizada uma análise descritiva e inferencial entre as variáveis levantadas na pesquisa em relação à situação do jogo. Resultados: Os resultados mostraram uma relação significativa entre as variáveis analisadas e a situação do jogo. A forma de agrupar os jogadores durante o desenvolvimento das tarefas de treinamento condiciona os resultados das demais variáveis que definem uma tarefa de treinamento, tanto ao nível pedagógico, organizacional e de carga externa. Conclusão: Estas evidências reafirmam a importância de conhecer os fatores que influenciam as tarefas de treinamento. Além disso, os resultados mostram que existem diferenças no uso de Situações de Jogo dependendo do resto das variáveis utilizadas.


Asunto(s)
Humanos , Educación y Entrenamiento Físico , Baloncesto , España , Tutoría
10.
Faraday Discuss ; 242(0): 23-34, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36200857

RESUMEN

In this work, nanoindentation of spherical NiCo nanoalloys with core-shell and random mixing patterns was studied, and we compared them against monometallic nanoparticles in order to investigate how the mechanical response may be influenced by the elemental distribution and the proportion of each element. Independently of the mixing patterns, plasticity begins with the nucleation of Shockley partial dislocations (SPDs) at the nanoparticle surface, on several slip planes, which leads to the appearance of sessile dislocations and either a stacking fault pyramid (SFP) or an open pyramid at the poles of the spherical nanoalloys. SPDs leave behind stacking faults but, for core-shell structures, the formation of nanotwins was also observed. It was also found that the presence of Co in the external shell of the nanoparticle has the effect of raising the yield strength, which could be interpreted in terms of unstable stacking fault energy. These results have relevance in the design of nanoalloys, since elemental distribution and stoichiometry can be used to tune the desired mechanical properties of the nanoparticle.

11.
Medicina (B Aires) ; 82(6): 914-926, 2022.
Artículo en Español | MEDLINE | ID: mdl-36571531

RESUMEN

Advances in knowledge incorporated in the last decade have modified the treatment paradigm in most of the malignant hematological diseases. In particular, the introduction of Bruton tyrosine kinase inhibitors (BTKi) and other target drugs together with new monoclonal antibodies have become agents of choice for both chronic lymphocytic leukemia (CLL) and other peripheral "B" lymphomas such as mantle cell lymphoma (MCL). The results of efficacy against genotoxic therapy are so successful that the end of chemoimmunotherapy, especially for CLL, is already a postulate recognized by the main research groups. On the other hand, the new drugs modified the profile of adverse events, which forced the development of new subspecialties such as cardio-oncology, which currently constitutes a bastion for the rational management of these patients. This review aims to highlight the current state of knowledge on these pathologies, pharmacological principles together with new adverse events of iBTK and the invaluable contribution of cardiology for correct management of these patients.


Los avances en el conocimiento incorporados en la última década han modificado en gran parte el paradigma del tratamiento de las enfermedades hematológicas malignas. Particularmente la introducción de los inhibidores de la Bruton tirosina quinasa (iBTK) y otras drogas blanco junto a nuevos anticuerpos monoclonales se han transformado en los agentes de elección, tanto para la leucemia linfática crónica (LLC) como para otros linfomas "B" periféricos como el linfoma de células del manto (LCM). Los resultados de eficacia frente a la terapia genotóxica son tan exitosos que el fin de la quimio inmunoterapia, sobre todo para la LLC, es ya un postulado reconocido por los principales grupos de investigación. Por otra parte, los nuevos fármacos modificaron el perfil de eventos adversos lo que obligó al desarrollo de nuevas subespecialidades como la cardiooncología, la cual constituye actualmente un baluarte para el manejo racional de estos pacientes. La presente revisión tiene como objetivo destacar el estado actual del conocimiento sobre estas enfermedades, los principios farmacológicos junto a los nuevos eventos adversos de los iBTK y el invalorable aporte de la cardiología para un correcto tratamiento y control de estos pacientes.


Asunto(s)
Antineoplásicos , Cardiólogos , Leucemia Linfocítica Crónica de Células B , Linfoma de Células del Manto , Humanos , Adulto , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/patología , Agammaglobulinemia Tirosina Quinasa , Linfoma de Células del Manto/tratamiento farmacológico , Linfoma de Células del Manto/patología , Antineoplásicos/efectos adversos
12.
Medicina (B.Aires) ; Medicina (B.Aires);82(6): 914-926, dic. 2022. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1422087

RESUMEN

Resumen Los avances en el conocimiento incorporados en la última década han modificado en gran parte el paradigma del tratamiento de las enfermedades hematológicas malignas. Particularmente la intro ducción de los inhibidores de la Bruton tirosina quinasa (iBTK) y otras drogas blanco junto a nuevos anticuerpos monoclonales se han transformado en los agentes de elección, tanto para la leucemia linfática crónica (LLC) como para otros linfomas "B" periféricos como el linfoma de células del manto (LCM). Los resultados de eficacia frente a la terapia genotóxica son tan exitosos que el fin de la quimio inmunoterapia, sobre todo para la LLC, es ya un postulado reconocido por los principales grupos de investigación. Por otra parte, los nuevos fármacos modificaron el perfil de eventos adversos lo que obligó al desarrollo de nuevas subespecialidades como la cardio-oncología, la cual constituye actualmente un baluarte para el manejo racional de estos pacientes. La presente revisión tiene como objetivo destacar el estado actual del conocimiento sobre estas enfermedades, los principios farmacológicos junto a los nuevos eventos adversos de los iBTK y el invalorable aporte de la cardiología para un correcto tratamiento y control de estos pacientes.


Abstract Advances in knowledge incorporated in the last decade have modified the treatment paradigm in most of the malignant hematological diseases. In particular, the introduction of Bruton tyrosine kinase inhibitors (BTKi) and other target drugs together with new monoclonal antibodies have become agents of choice for both chronic lym phocytic leukemia (CLL) and other peripheral "B" lymphomas such as mantle cell lymphoma (MCL). The results of efficacy against genotoxic therapy are so successful that the end of chemoimmunotherapy, especially for CLL, is already a postulate recognized by the main research groups. On the other hand, the new drugs modified the profile of adverse events, which forced the development of new subspecialties such as cardio-oncology, which currently constitutes a bastion for the rational management of these patients. This review aims to highlight the current state of knowledge on these pathologies, pharmacological principles together with new adverse events of iBTK and the invaluable contribution of cardiology for correct management of these patients.

13.
Artículo en Inglés | MEDLINE | ID: mdl-36231390

RESUMEN

Constructivism is used as a powerful theoretical outlook to support teaching, learning, and curriculum in physical education and sport. The Constructivist Teaching Practices Inventory in Elementary Physical Education (CTPI-EPE) is a valid instrument for assessing in-service teachers. However, there is a need to translate constructivist teaching practices for PE into other languages. This study examined the validity of the Portuguese version of the adapted CTPI-EPE for Brazilian physical education preservice teachers (PST). The sample comprised of 869 physical education PSTs from Brazil. Data were collected through an online form. Aiken's V was used to examine content validity, and Bayesian methods used for exploratory and confirmatory factor analysis. The results showed adequate content and internal structure of the translated and adapted questionnaire. This study highlighted the validity of the Portuguese version of the CTPI-EPE, which could be considered an important instrument for self-reflection by PSTs, and provide information for improved training in higher education toward constructivist teaching.


Asunto(s)
Educación y Entrenamiento Físico , Teorema de Bayes , Brasil , Análisis Factorial , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
14.
Sensors (Basel) ; 22(12)2022 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-35746216

RESUMEN

This study aimed to investigate how different strategies of task constraint manipulation impact physical and tactical demands in small-sided and conditioned games (SSCG). Ten recreational U-17 soccer players participated in this study (16.89 ± 0.11 years). We used different strategies of task manipulation to design two 4 vs. 4 SSCG: Structural SSCG and Functional SSCG. In Structural SSCG, pitch format and goal sizes were manipulated, while in Functional SSCG, players were allowed to kick the ball twice and at least 5 passes to shoot at the opponent's goal. Players participated in four Structural and Functional SSCG, of five minutes duration with a two-minute interval in between. Players' physical performance and tactical behavior were assessed using the WIMU PROTM inertial device. Structural SSCG stimulated players to cover more distance in sprinting (p = 0.003) and high-speed running (p < 0.001). Regarding tactical behavior, Structural SSCG stimulated players to explore game space better (p < 0.001). Moreover, Functional SSCG stimulated players to be closer to the ball, decreasing the effective playing space (p = 0.008). We conclude that these strategies of task constraint manipulation impact physical and tactical demands of the game.


Asunto(s)
Rendimiento Atlético , Carrera , Fútbol , Motivación , Rendimiento Físico Funcional
15.
Front Vet Sci ; 9: 852650, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35529838

RESUMEN

Aujeszky's disease (AD) is endemic in Argentina. In 2016, an inactivated gE- negative marker Bartha K61 vaccine (AUSKIPRA® BK) was launched for use, making Argentina the only country to carry out a control strategy plan with it. In the present article, we describe the results of a control program in a farrow-to-finishing farm with high initial AD prevalence (33% in sows), based on the systematic vaccination, detection, and elimination of seropositive pigs, the replacement of sows with vaccinated gilts, and the instauration of artificial insemination. The program was suitable for diminishing the incidence and the prevalence at levels consistent with virus eradication. This situation has been sustained over time. This is the first report of AUSKIPRA® BK efficacy under field conditions.

16.
Sensors (Basel) ; 22(10)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35632283

RESUMEN

Steel-concrete composite systems are an efficient alternative to mid- and high-rise building structures because of their high strength-to-weight ratio when compared to traditional concrete or steel constructive systems. Nevertheless, composite structural systems are susceptible to damage due to, for example, deficient construction processes, errors in design and detailing, steel corrosion, and the drying shrinkage of concrete. As a consequence, the overall strength of the structure may be significantly decreased. In view of the relevance of this subject, the present paper addresses the damage detection problem in a steel-concrete composite structure with an impact-hammer-based modal testing procedure. The mathematical formulation adopted in this work allows for the identification of regions where stiffness varies with respect to an initial virgin state without the need for theoretical models of the undamaged structure (such as finite element models). Since mode shape curvatures change due to the loss of stiffness at the presence of cracks, a change in curvature was adopted as a criterion to quantify stiffness reduction. A stiffness variability index based on two-dimensional mode shape curvatures is generated for several points on the structure, resulting in a damage distribution pattern. Our numerical predictions were compared with experimentally measured data in a full-scale steel-concrete composite beam subjected to bending and were successfully validated. The present damage detection strategy provides further insight into the failure mechanisms of steel-concrete composite structures, and promotes the future development of safer and more reliable infrastructures.

17.
An Acad Bras Cienc ; 94(suppl 1): e20210805, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35508022

RESUMEN

Carbonaceous aerosols can affect climate, especially particles containing black carbon (BC). BC originated from the incomplete combustion of fossil fuel and biomass, which can heat the atmosphere and increase ice melting, but little is known about BC sources to Antarctica. We quantified the contribution of distant origin (biomass burning) and local emissions (fossil fuel) to atmospheric BC concentration in the King George Island (Antarctic Peninsula) and the Southern Ocean. We examine the BC concentrations using a multi-wavelength Aethalometer AE-33 and AE-42 aboard the Brazilian Oceanographic Research Ship Almirante Maximiano. The results indicate that the region is influenced by local sources and air masses coming from surrounding continents. Fossil fuel combustion was the major source of carbonaceous aerosols in the region, whereas the total average concentration was 41.8 ± 22.8 ng m-3. The findings indicate a contribution of biomass burning coming from low and mid-latitudes of South America over the Antarctic Peninsula and the Southern Ocean around 62ºS latitude. We demonstrated that fossil fuel is the main contributor to atmospheric BC concentration for the Austral summer and autumn. Scientific stations, local tourism, and traffic are possible local BC sources. Our work invokes the urgency of questionable sustainability issues about Antarctica exploration.


Asunto(s)
Contaminantes Atmosféricos , Combustibles Fósiles , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Regiones Antárticas , Océano Atlántico , Biomasa , Brasil , Carbono/análisis , Monitoreo del Ambiente/métodos , Combustibles Fósiles/análisis , Estaciones del Año
18.
Gac Med Mex ; 158(M3): M1-M48, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35350063

RESUMEN

Acute myeloid leukemia (AML) comprises a heterogeneous group of hematopoietic cell neoplasms of myeloid lineage that arise from the clonal expansion of their precursors in the bone marrow, interfering with cell differentiation, leading to a syndrome of bone marrow failure. AML is a consequence of genetic and epigenetic changes (point mutations, gene rearrangements, deletions, amplifications, and arrangements in epigenetic changes that influence gene expression) in hematopoietic precursor cells, which create a clone of abnormal cells that are capable of proliferating but cannot differentiate into mature hematopoietic cells or undergo programmed cell death. The diagnosis requires more than 20% myeloid blasts in the bone marrow and certain cytogenic abnormalities. Treatment will depend on age, comorbidities, and cytogenetic risk among the most frequent.


La leucemia mieloide aguda (LMA) comprende un grupo heterogéneo de neoplasias de células hematopoyéticas de linaje mieloide que surgen de la expansión clonal de sus precursores en la médula ósea, interfiriendo con la diferenciación celular, lo que conlleva a un síndrome de falla medular. La LMA es una consecuencia de cambios genéticos y epigenéticos (mutaciones puntuales, rearreglos de genes, deleciones, amplificaciones y arreglos en cambios epigenéticos que influyen en la expression del gen) en las células hematopoyéticas precursoras, la cual crea una clona de células anormales que son capaces de proliferar, pero no se pueden diferenciar en células hematopoyéticas maduras ni sufrir una muerte celular programada. El diagnostic requiere más del 20% de blastos mieloides en médula ósea y ciertas anormalidades citogénicas. El tratamiento dependerá de la edad, comorbilidades, riesgo citogenético entre las más frecuentes.


Asunto(s)
Leucemia Mieloide Aguda , Diferenciación Celular , Consenso , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , México
19.
Artículo en Inglés | MEDLINE | ID: mdl-35010719

RESUMEN

In spite of the negative effects of anger, coaches are often seen becoming angry during games. This is especially worrying in U18 categories. Thus, the objective of this study was to identify the influence that the coach's anger has on the performance of a basketball team in competition. For this, an ad hoc observation tool was designed, in which 587 moments of anger from the coaching staff (64 coaches) were recorded in the 24 semi-final and final matches of the Spanish Autonomous Region Team Championships in 2019 and 2020 in the infantil (M = 14 years old) and cadete (M = 16 years old) categories. The results show that, in response to most incidents of coach anger, the performance of the team did not change. Significant differences were identified in some scenarios, with low- or medium-intensity anger targeted at the defence, where the team performance improved. However, anger towards the referee in the last quarter with scores level had a negative influence on the team's performance.


Asunto(s)
Baloncesto , Tutoría , Adolescente , Ira , Ansiedad , Humanos
20.
Sci Total Environ ; 807(Pt 2): 151231, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-34715230

RESUMEN

The Abrolhos bank is home of the richest coral reef system of the Southwestern Atlantic, where endemic coral species are found. It has been reported that Abrolhos' corals are under intense stress due to increasing of Marine Heat Waves during the last decades. Additionally, anthropic interventions along the adjacent coastal regions are a factor of concern since they contribute to the increase in the sediment load and to organic debris input in the reef domain. In November 2015, the collapse of the Fundão mining tailings dam resulted in the release of approximately 50 million m3 of iron oxide and quartz-rich slurry into the Doce River. Aiming at using a fingerprint of the tailings and to assess the presence of traces of the Fundão dam material from this event on the Abrolhos bank, this work presents new 87Sr/86Sr and 143Nd/144Nd isotope ratios of marine suspended sediment samples collected between 2016 and 2020 from a network of sediment traps throughout the reef and complementary suspended material at sea. In parallel, we monitored meteo-oceanographic parameters and modeled surface marine currents as an attempt to identify the sediment transport between the Doce River mouth and Abrolhos bank. The r isotopes were used as provenance proxies based on the fact that minerals and rocks tend to have specific isotopic signatures reflecting their own geological derivation. In this context, the isotopic ratios of various potential regional sources for the sedimentation in Abrolhos bank were evaluated. Our monitoring and isotopic measurements indicate that Doce River signatures are detected at Abrolhos bank, following the seasonal Doce River discharge at sea. Isotopic signature of Doce River at Abrolhos bank was also observed during the austral winter (July-August) when cold fronts migrate at the Brazilian coast with higher frequency and energy.


Asunto(s)
Antozoos , Colapso de la Estructura , Animales , Brasil , Arrecifes de Coral , Sedimentos Geológicos , Isótopos
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