Thermodynamic and dynamic anomalies for a three dimensional isotropic core-softened potential

Using molecular dynamics simulations and integral equations (Rogers-Young, Percus-Yevick and hypernetted chain closures) we investigate the thermodynamic of particles interacting with continuous core-softened intermolecular potential. Dynamic properties are also analyzed by the simulations. We show that, for a chosen shape of the potential, the density, at constant pressure, has a maximum for a certain temperature. The line of temperatures of maximum density (TMD) was determined in the pressure-temperature phase diagram. Similarly the diffusion constant at a constant temperature, $D$, has a maximum at a density $\rho_{max}$ and a minimum at a density $\rho_{min}<\rho_{max}$. In the pressure-temperature phase-diagram the line of extrema in diffusivity is outside of TMD line. Although in this interparticle potential lacks directionality, this is the same behavior observed in SPC/E water.Comment: 16 page

Knowledge of family health program practitioners in Brazil about sickle cell disease: a descriptive, cross-sectional study

BACKGROUND: Although sickle cell disease is an important public health problem in Brazil, there is a gap in the literature on the level of knowledge of primary health care professionals about the treatment and management of sickle cell disease. Therefore, this study aimed to evaluate the level of knowledge about sickle cell disease of physicians and nurses who work in the Family Health Program in a region of Brazil with a high prevalence of this disease. METHODS: This is a descriptive, cross-sectional study conducted at the municipality of Montes Claros, in the north of Minas Gerais, Brazil. Study participants included 96 physicians and nurses who work at the Family Health Program in an urban area of the city. Data was collected using an original, partially tested questionnaire based on health care check points for children with sickle cell disease established in educational protocols from the State Health Secretary of Minas Gerais and the Ministry of Health. The structured questionnaire contained 47 questions addressing three axes: epidemiology (8 questions); clinical manifestations (13 questions); and management of children with sickle cell disease (26 questions). Knowledge was measured through mean correct responses to proposed questions. Ethical principles were respected and this project was approved by the Committee of Ethics in Research. RESULTS: 59.4% (57) of the study participants were nurses and 40.6% (39) were physicians. The median length of training and median length of service in primary health care were 4.3 (2.8-8.0) years and 4.0 (2.0-7.1) years, respectively. The mean performance in knowledge tests was < 75%, with 5.7/8 (SD = 1.4) for the "epidemiology" questions; 8.6/13 (SD = 2.2) for "clinical manifestations"; and 17.0/26 (SD = 2.9) for "management of children with sickle cell disease" questions; resulting in a mean total of 31.4/47 (SD = 5.10) correct responses. A statistically significant association was found between the number of correct responses and family health care qualifications (p = 0.015). CONCLUSION: There is an urgent need to improve primary health care professional training in the care of children with sickle cell disease

Experiencia estética y desarrollo sostenible: Un estudio de caso

A partir de la pregunta de cómo pueden contribuir las artes para la comunicación sobre desarrollo sostenible, el estudio hace un análisis sociológico-antropológico de la recepción de una exposición internacional de arte contemporáneo sobre sostenibilidad en Valparaíso, Chile. La experiencia estética del público comprueba que el arte, a través de componentes sensuales y estrategias estéticas que conducen a la reflexión, puede fertilizar la susceptibilidad a cuestiones de desarollo sostenible. Esa potencialidad es capaz de identificar lagunas en la discusión pública local sobre sostenibilidad, pero no es capaz de rellenarlas.Palabras clave: Experiencia estética; sostenibilidad; arte contemporáneo; Valparaíso

Multifunctional Hybrid MoS2-PEGylated/Au Nanostructures with Potential Theranostic Applications in Biomedicine

In this work, flower-like molybdenum disulfide (MoS2) microspheres were produced with polyethylene glycol (PEG) to form MoS2-PEG. Likewise, gold nanoparticles (AuNPs) were added to form MoS2-PEG/Au to investigate its potential application as a theranostic nanomaterial. These nanomaterials were fully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), photoelectron X-ray spectroscopy (XPS), Fourier-transformed infrared spectroscopy (FTIR), cyclic voltammetry and impedance spectroscopy. The produced hierarchical MoS2-PEG/Au microstructures showed an average diameter of 400 nm containing distributed gold nanoparticles, with great cellular viability on tumoral and non-tumoral cells. This aspect makes them with multifunctional characteristics with potential application for cancer diagnosis and therapy. Through the complete morphological and physicochemical characterization, it was possible to observe that both MoS2-PEG and MoS2-PEG/Au showed good chemical stability and demonstrated noninterference in the pattern of the cell nucleus, as well. Thus, our results suggest the possible application of these hybrid nanomaterials can be immensely explored for theranostic proposals in biomedicine

Didactic Sequence for Teaching Exponential Function

This paper presents a methodological proposal for the teaching of exponential function, resulting from the application of a didactic sequence involving exponential function, where evidence of learning and the consolidation and application of mathematical concepts in problem solving were identified and analyzed. The Didactic Engineering of Michèle Artigue (1988) was used as a research methodology. As theoretical contributions that guided and enabled the development of the research, we chose the use of Mathematical Investigation in the classroom; Didactic Sequence in the conception of Zabala (1999); the Articulated Units of Conceptual Reconstruction proposed by Cabral (2017) and assumptions of Vygotsky\u27s theory. A didactic sequence composed of five UARC\u27s was elaborated to work the exponential function, with a view to minimizing the difficulties naturally imposed by the content to be explained. Microgenetic analysis of verbal interactions between teacher and students was used to analyze the results of the application. The results show that the students participating in the experiment showed evidence of learning, recorded during the process, and began to have a good understanding of the concepts and properties related to the topic, in addition to a good performance in carrying out the activities, facts that corroborate the potential of the didactic sequence proposed herein

Systematic analysis of jellyfish galaxy candidates in Fornax, Antlia, and Hydra from the S-PLUS survey: A self-supervised visual identification aid

© 2024 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/We study 51 jellyfish galaxy candidates in the Fornax, Antlia, and Hydra clusters. These candidates are identified using the JClass scheme based on the visual classification of wide-field, twelve-band optical images obtained from the Southern Photometric Local Universe Survey. A comprehensive astrophysical analysis of the jellyfish (JClass > 0), non-jellyfish (JClass = 0), and independently organized control samples is undertaken. We develop a semi-automated pipeline using self-supervised learning and similarity search to detect jellyfish galaxies. The proposed framework is designed to assist visual classifiers by providing more reliable JClasses for galaxies. We find that jellyfish candidates exhibit a lower Gini coefficient, higher entropy, and a lower 2D Sérsic index as the jellyfish features in these galaxies become more pronounced. Jellyfish candidates show elevated star formation rates (including contributions from the main body and tails) by 1.75 dex, suggesting a significant increase in the SFR caused by the ram-pressure stripping phenomenon. Galaxies in the Antlia and Fornax clusters preferentially fall towards the cluster's centre, whereas only a mild preference is observed for Hydra galaxies. Our self-supervised pipeline, applied in visually challenging cases, offers two main advantages: it reduces human visual biases and scales effectively for large data sets. This versatile framework promises substantial enhancements in morphology studies for future galaxy image surveys.Peer reviewe

Falls among older adults in the South of Brazil: prevalence and determinants

OBJETIVO: Avaliar a prevalência e os fatores associados à ocorrência de quedas em idosos. MÉTODOS: Estudo transversal com amostra representativa de 1.451 idosos residentes na zona urbana de Pelotas, RS, em 2014. Foi realizada análise descritiva dos dados e apresentada a prevalência de quedas no último ano. A análise de fatores demográficos, socioeconômicos, comportamentais e de saúde associados ao desfecho foi realizada por meio de regressão de Poisson com ajuste para variância robusta conforme modelo hierárquico. As variáveis foram ajustadas entre si dentro de cada nível e para as de nível superior. Aquelas com p ≤ 0,20 foram mantidas no modelo para controle de confusão e aquelas com p &lt; 0,05 foram consideradas associadas ao desfecho. RESULTADOS: A prevalência de quedas em idosos no último ano foi de 28,1% (IC95% 25,9–30,5), e a maioria ocorreu na própria residência do idoso. Entre os idosos que sofreram queda, 51,5% (IC95% 46,6–56,4) tiveram uma única queda e 12,1% (IC95% 8,9–15,3) tiveram fratura como consequência, sendo a de membros inferiores a mais relatada. A prevalência de quedas foi maior em mulheres, idosos com idade avançada, de menor renda e escolaridade, com incapacidade funcional para atividades instrumentais e portadores de enfermidades como diabetes, doença cardíaca e artrite. CONCLUSÕES: A ocorrência de quedas atingiu quase um terço dos idosos, e a prevalência foi mais elevada em segmentos específicos da população em questão. Cerca de 12% dos idosos que caíram, fraturaram algum osso. Os fatores associados à ocorrência de quedas identificados neste estudo poderão nortear medidas que visem sua prevenção na população de idosos.OBJECTIVE: Evaluate the prevalence and the factors associated with the occurrence of falls among older adults. METHODS: A cross-sectional study with a representative sample of 1,451 elderly residents in the urban area of Pelotas, RS, in 2014. A descriptive analysis of the data was performed and the prevalence of falls in the last year was presented. The analysis of demographic, socioeconomic, behavioral and health factors associated with the outcome was performed using Poisson regression with adjustment for robust variance according to the hierarchical model. The variables were adjusted to each other within each level and for the higher level. Those with p ≤ 0.20 were maintained in the model for confounding control and those with p &lt; 0.05 were considered to be associated with the outcome. RESULTS: The prevalence of falls among older adults in the last year was 28.1% (95%CI 25.9–30.5), and most occurred in the person’s own residence. Among the older adults who fell, 51.5% (95%CI 46.6–56.4) had a single fall and 12.1% (95%CI 8.9–15.3) had a fracture as a consequence, usually in the lower limbs. The prevalence of falls was higher in women, adults of advanced age, with lower income and schooling level, with functional incapacity for instrumental activities, and patients with diseases such as diabetes, heart disease, and arthritis. CONCLUSIONS: The occurrence of falls reached almost a third of the older adults, and the prevalence was higher in specific segments of the population in question. About 12% of the older adults who fell fractured some bone. The factors associated with the occurrence of falls identified in this study may guide measures aimed at prevention in the older adult population