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Reliability of a computational model for evaluating thoracoabdominal mobility in newborns: a cross‑sectional study
No full textThe present study aimed to verify the inter and intra-examiner reliability of an interactive custom-made MATLAB (R) App for bio-photogrammetric analysis of thoracoabdominal mobility in newborns and compare the respiratory rate (RR) results between the automatic MATLAB (R) App and its manual counterpart. This is a cross-sectional study conducted in 27 healthy newborns of both sexes (gestational age between 37 and 41 weeks and up to 72 h of life) who did not cry during data acquisition. Chest and abdominal areas of the subjects in the supine position were analyzed through 60 s videos, totaling 30,714 photograms. All photograms were analyzed by three examiners on three different occasions. Analysis of variance (ANOVA) and intraclass correlation coefficient (ICC) were applied, adopting a 95% confidence interval and significance level of alpha = 0.05. Reliability was excellent for intra (ICC 0.81-0.96) and inter-examiner correlations (ICC 0.84-0.99) between the chest and abdominal areas, in both inspiration and expiration, with no differences between them. Evaluation of newborns' thoracoabdominal mobility using the custom-made MATLAB (R) App for bio-photogrammetric analysis exhibited good to excellent intra- and inter-examiner reliability and an excellent correlation between manual and automatic models for measuring RR. Thus, it proved to be an objective and practical tool for bedside thoracoabdominal mobility assessment in different clinical situations involving neonatal care
Thermodynamic model of life-cycle deterioration of seismic resistance for complex RC structures by coupling corrosion and cracking damage
No full textThe durability and service life of reinforced concrete (RC) structural components in bridges and frames are limited by the susceptibility of the reinforcement to corrosion. Corrosion leads to a reduction in the cross-section of the rebar and degrades its material properties. Severe corrosion and damage to stirrups can trigger buckling of the longitudinal bars. Additionally, it has been reported that concrete cracking, caused by mechanical forces, accelerates the corrosion process. The fundamental cause or driving force for all corrosion is the lowering of the system's Gibbs energy. Based on a lumped damage model and the theory of the thermodynamics of solids, coupling relations of three internal variables (concrete cracking damage, reinforcement plasticity, and corrosion level) are proposed. This macro -model also allows for considering buckling of longitudinal bars and loss of confinement due to corrosion of the transverse reinforcement. By combining available time -dependent corrosion laws with lumped damage constitutive equations, it is possible to predict the life -cycle resistance of RC bridge columns and frames and simulate their behavior when subjected to extreme loading in a corrosive environment. Earthquake forces are considered as an example of such kind of extreme loading. The thermodynamic formulation extends the range of applicability for the available corrosion laws in the literature by including the influence of concrete cracks. Two parametric examples demonstrate the potential applications of the model, including the estimation of critical mass loss for specific structures and the reduction of service life after medium -intensity earthquakes. The accuracy, effectiveness, and computational efficiency of the proposed model are fully verified in terms of the comparisons of experimental and numerical results
Scale Mixture of Gleser Distribution with an Application to Insurance Data
No full textIn this paper, the scale mixture of the Gleser (SMG) distribution is introduced. This new distribution is the product of a scale mixture between the Gleser (G) distribution and the Beta(a,1) distribution. The SMG distribution is an alternative to distributions with two parameters and a heavy right tail. We study its representation and some basic properties, maximum likelihood inference, and Fisher's information matrix. We present an application to a real dataset in which the SMG distribution shows a better fit than two other known distributions
Comparative Study of New A<sub>3</sub> and A<sub>2</sub>B Aluminum Corroles by Absorption and Charge Transport Properties
No full textNew materials for applications in energy conversion systems as solar cells or lighting devices, avoiding expensive and scarce metals is desirable, therefore, aluminum corroles appear as alternative, since these compounds are relatively less expensive, and the electronic modulation appears as an interesting tuning to achieve good performance in optical devices. In this sense, this research presents a theoretical study of new aluminum corroles containing electron-withdrawing substituents on the meso-carbons of the macrocycle. The first family of corroles comprises three A(3) structures (AlCo1, AlCo2 and AlCo3) that contain NO2-phenyl and CF3-phenyl substituents, and the second family comprises three A(2)B structures (AlCo4, AlCo5 and AlCo6) with a pyrenyl substituent on the 10 meso-carbon. All the calculations were obtained by Density Functional Theory using B3LYP functional and 6-31G(d,p) basis set for all atoms evaluating their geometrical parameters, absorption properties and injection/transport charge transfer processes. The results show that the corroles have strong absorption processes extended from blue to near infrared region, being favored the absorption shifted to red in A(2)B structures and with para NO2-phenyl substituents. Furthermore, the calculated charge transfer processes showed interesting values demonstrating that these macrocyclic compounds could be useful for optoelectronic applications such as solar cells or lighting devices
Textos escolares y debates en torno a los pueblos indígenas en Chile
Get PDFSe exponen antecedentes respecto de las propuestas de los textos escolares en Chile, referido a los pueblos indígenas, identificando en ellos sesgos coloniales y racistas. En este sentido, el objetivo de fondo de esta propuesta es identificar el sentido de los textos escolares que llegan a los y las estudiantes chilenas. Todo lo anterior a partir del estudio de las representaciones sociales vertidas en libros de historia escolar. Tensionamos la literalidad de los textos con la imagen que expresan de los pueblos indígenas, y con el esquema ideológico difundido por el sistema escolar en su conjunto, a la hora de expresar su opinión/valoración de la historia de los pueblos indígenas. Los resultados de la investigación permiten distinguir un discurso antiindígena, que centra su potencial en un ejercicio de ecuación histórica que relega la historia y figura indígena al pasado, al olvido y a la negación.
Abstract
Background is presented regarding the proposals of the school texts in Chile, referring to indigenous peoples, identifying in them colonial and racist biases. In this sense, the main objective of this proposal is to identify the meaning of the school texts that reach Chilean students. All of the above from the study of social representations poured into school history books. We stress the literal nature of the texts with the image they express of indigenous peoples, and with the ideological scheme disseminated by the school system as a whole, when expressing their opinion / appreciation of the history of indigenous peoples. The results of the research make it possible to distinguish an anti-indigenous discourse, which focuses its potential on an exercise of historical equation that relegates history and indigenous figure to the past, oblivion and denial
Feasibility, Clinical Efficacy, and Maternal Outcomes of a Remote Exercise Program in Pregnant Women with Obesity: The GROB Randomized Control Pilot Study
No full textBackground: Obesity is common in women of reproductive age and increases the risk during pregnancy. Exercising during this period reduces health complications. Home e -health programs are effective in overcoming exercise barriers as pregnant women use technology and the internet for health information. Methods: A single -blind randomized controlled feasibility study with pregnant women with obesity (body mass index [BMI] >= 30 kg/m2) was conducted in the University Hospital Center of Sao Joao between January and April 2023. Pregnant women were randomized to a control group with standard care and to an experimental group with 8-week remote exercise program using a Phoenix (R) biofeedback device. Feasibility outcome measures were recruitment rate (>= 35%), loss to follow-up (= 1 session/week). Secondary outcomes were evaluated through Pregnancy Physical Activity Questionnaire, Oswestry Index on Disability, and weight assessments at baseline and at the end of the program. Results: Of the 63 eligible participants, 24 (38.1%) were successfully randomized and completed the baseline assessment. Of these, 3 (4.8%) from experimental group did not perform the initial onboarding. The control group had 8.3% of follow-up losses and for the experimental group there were no follow-up losses. Program fidelity (mean >= 1 session/week) was fulfilled by 66.7% of successfully randomized participants. Regarding secondary outcomes assessed between baseline and the 8th week, experimental group compared to control group had higher levels of physical activity for sports activities, a lower level of inactivity, and lower disability rates caused by low back pain. Conclusions: Based on the recruitment rate, losses to follow-up, and fidelity rate, the GROB (obesity in pregnancy) study was deemed feasible and worthy of consideration for a larger study. Moreover, the GROB study has the potential to improve maternal outcomes by reducing sedentarism and disability caused by low back pain. Clinical Trial Registration: The study has been registered on https://classic.clinicaltrials.gov/ (registration number: NCT05331586)
Rhizosphere-inhabiting fungi isolated from native plants of the atacama desert affect leaf traits of chardonnay' grapevines (<i>Vitis vinifera</i> L.)
No full textStudying new alternatives for promoting plant growth is crucial to face a changing climate. This study aimed to determine the beneficial effect of fungal strains isolated from the rhizospheric soil of two native plants from the Atacama Desert on physiological leaf traits of inoculated 'Chardonnay' grapevines. Rhizosphere fungi were isolated from Baccharis scandens and Solanum chilense and tested in vitro for plant growth-promoting traits, including indole acetic acid, phosphate solubilization, siderophore production, and polyamine production. Aspergillus niger, Microdochium bolleyi, and Westerdikeya centenaria were isolated, showing plant growth-promoting attributes and high salt tolerance in almost all tested isolates. Then, the fungi were stabilized and co-inoculated in pot-grown 'Chardonnay' plants (Vitis vinifera L.) growing in outdoor conditions to evaluate gas exchange variables, chlorophylls (as SPAD value), water potential, proline and sugar content, and lipid peroxidation in leaves. Inoculation of the fungal strains significantly increased the photosynthesis rate, which was associated with higher mesophyll conductance and SPAD values. The co-inoculation also induced an enhanced protective condition for oxidative damage. Increased carbon assimilation resulted in higher soluble sugars and intrinsic water use efficiency in leaves without altering the water status of treated plants. Our results demonstrated the beneficial effects of co-inoculating rhizosphere-inhabiting fungi isolated from native plants from the Atacama Desert on physiological traits of 'Chardonnay' grapevines
Analysis of Food Security of Older Rural Indigenous People in Latin America and the Caribbean
No full textFood insecurity is a critical issue in the Americas, with severe impacts in the Caribbean, Mesoamerica, and South America, particularly affecting older adults in Indigenous and rural contexts where it intersects with poverty, gender, and ethnicity. This study aims to provide an in-depth understanding of the current research about food insecurity among older Indigenous adults in Latin America and the Caribbean. A comprehensive literature review was conducted, utilizing specific search queries and the population, intervention, comparison, and outcome (PICO) strategy across multiple databases to identify the pertinent studies. The findings indicate an increase in academic output on this topic since 2018, with significant emphasis on the interplay between climate change and food insecurity. The review highlights the importance of developing targeted food programs, reforming policies, and fostering collaboration between academia and local communities to implement practical interventions. Despite the growing body of literature, a notable research gap persists in rural areas of Latin America and the Caribbean. This study underscores the necessity of balancing the geographic distribution of research and emphasizes the preservation of cultural practices and the adaptation of public policies to support traditional food practices. It advocates for culturally sensitive interventions and interdisciplinary collaboration to formulate comprehensive strategies. The originality and value of this study lie in its focused analysis of older Indigenous adults, contributing crucial insights to the international literature on food security
A new generalization of the maxwell distribution
Get PDFA new univariate three-parameter distribution, the transmuted exponentiated Maxwell distribution, is proposed and studied. This new univariate distribution can be seen as generalization of the Maxwell distribution and its respective exponentiated and transmuted versions. The new generalization is generate using the families of exponentiated and transmuted distributions. Some probabilistic properties are studied, maximum likelihood estimation discussed, derive the functions to be used in reliability studies and present an application with a real data. We hope that the new distribution proposed will serve as an alternative model to the Maxwell and the respective exponentiated and transmuted versions
Indigenous socio-educational recognition in the construction of intercultural knowledge dialogues in education
No full textThis article aims to analyze indigenous socio-educational knowledge to build an intercultural knowledge dialogue in the school curriculum, using educational experience from a Mapuche context in Chile. Based on the knowledge of teachers, indigenous scholars, and parents, the article outlines three ways to guide the construction of a knowledge dialogue when implementing intercultural education. The methodology uses a comprehensive interpretative paradigm. The results reveal that indigenous socio-educational recognition for intercultural knowledge dialogue in an educational environment is essential for changing the school's epistemological colonialism, monoculturalism, and disconnect from the territory. The work highlights the importance of exploring the potentialities of intercultural dialogue to overcome the socio-educational and socio-cultural ambivalence of actors in the school setting, as well as the hegemony of a Eurocentric curriculum. Thus, the contribution to the educational debate is linked to the presentation of contextualized and intercultural guidelines that serve as references for the actors in the educational field, in the challenge of achieving decolonized coexistence