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Estudio de prefactibilidad técnica-económica para la creación de una empresa de mantenimiento eléctrico en condominios de la Región Metropolitana
No full textTesis no posee resumen ni abstrac
The Effects of Lockdown, Urban Meteorology, Pollutants, and Anomalous Diffusion on the SARS-CoV-2 Pandemic in Santiago de Chile
No full textPublisher Copyright: © 2024 by the authors.A study was carried out in Santiago de Chile, located in a geographic basin, on the sustainability and diffusion of the recent SARS-CoV-2 pandemic. Hourly measurements were used (carried out for 3.25 years in seven communes of the city) to quantify the accumulated sick (AS) population, urban meteorology variables (MVs) (temperature (T), relative humidity (RH), and magnitude of wind speed (WS)), and air pollution (P) (PM10, PM2.5, 03). Time series (TS) were constructed for each commune, which related AS to MVs, called AS/VM, and to P, noted AS/P. Chaos theory was applied to each TS, requiring the following variables: the Lyapunov exponent (λ > 0), the correlation dimension (DC 0), the Hurst exponent (H, such that 0 0), and information loss ( < 0). Every TS complied with chaos theory. For each commune, CK was calculated as a quotient between the sum of AS/T, AS/WS, and AS/RH entropies and the sum of AS/PM10, AS/PM2.5, and AS/O3 entropies. The results show that the entropy for the AS/P ratio is lower than that of the AS/VM ratio in three of the seven communes, since between 2020 and early 2022, the population was confined, reducing pollution. The TS of the AS/P ratio is more persistent and complex. The predictability times of the ratios are comparable in four of the seven communes. The TS of the AS/MV ratios shows greater information loss and chaos. According to the calculated CK values, it is possible to relate it to anomalous diffusion (sub/super-diffusion) and the context that favored the expansion of the pandemic: urban densification, pollution, urban meteorology, population density, etc. Using Fréchet heavy-tailed probability, the compatibility of the results with CK is verified
Magnetic field dependence of the neutral pion longitudinal screening mass in the linear sigma model with quarks
No full textPublisher Copyright: © 2024 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3.We use the linear sigma model with quarks to study the magnetic-field-induced modifications on the longitudinal screening mass for the neutral pion at one-loop level. The effects of the magnetic field are introduced into the self-energy, which contains the contributions from all the model particles. We find that, to obtain a reasonable description for the behavior with the field strength, we need to account for the magnetic field dependence of the particle masses. We also find that the couplings need to decrease fast enough with the field strength to then reach constant and smaller values as compared to their vacuum ones. The results illustrate the need to treat the magnetic corrections to the particle masses and couplings in a self-consistent manner, accounting for the backreaction of the field effects for the magnetic field dependence of the rest of the particle species and couplings in the model
Hamstring Muscles. Analysis of its Use and Proposal for Inclusion in Terminologia Anatomica
No full textPublisher Copyright: © 2024, Universidad de la Frontera. All rights reserved.The Terminologia Anatomica published in 2019 in English and 2001 in Spanish conTAIns the official names of anatomical structures. However, there are terms that are not included in this terminology, and are widely used, such as the term “hamstring muscles. The objective of this work was to analyze the use of the terms hamstring muscles, muscles of the posterior compartment of thigh and muscles of the flexor compartment of thigh. A narrative review was carried out that included 37 anatomy books, 3 dictionaries of medical and biological terminology, 10 databases and 15 digital resources. Results: In the books published after 2001, 55.6 % used the term hamstring muscles, 18.5 % muscles of the posterior compartment of thigh and 0 % muscles of the flexor compartment of thigh; In no dictionary was the use of the terms hamstring muscles, muscles of the posterior compartment of thigh or muscles of the flexor compartment of thigh found; In the databases, 12,104 articles were found with the term hamstring muscles, 5 with the term muscles of the posterior compartment of thigh and 1 with the term muscles of the flexor compartment of thigh; In the digital anatomy resources, 50 % used the term hamstring muscles, 37.5 % the term muscles of the posterior compartment of thigh and 12.5 % muscles of the flexor compartment of thigh. In conclusion, the use of the term hamstring muscles far exceeds the use of the terms indicated by the International Anatomical Terminology. Additionally, this term is anatomically descriptive and univocal. In this regard, it seems appropriate to assess the incorporation of the term hamstring muscles in Terminologia Anatomica.Terminologia Anatomica Internacional publicada el año 2019 en inglés y el 2001 en español contiene los nombres oficiales de las estructuras anatómicas. Sin embargo, existen términos que no están incluidos en esta terminología, y son ampliamente utilizados, es el caso del término músculos isquiotibiales. El objetivo de este trabajo fue analizar la utilización del término músculos isquiotibiales, músculos del compartimento femoral posterior y músculos del compartimento femoral flexor. Se realizó una revisión narrativa que incluyó 37 libros de anatomía, 3 diccionarios de terminología médica y biológica, 10 bases de datos y 15 recursos digitales. En los libros publicados después del año 2001 el 55,6 % utilizaba el término músculos isquiotibiales y el 18,5 % utilizó músculos del compartimento femoral posterior. En ningún diccionario se encontró el uso de los términos músculos isquiotibiales, músculos del com- partimento femoral posterior ni músculos del compartimento femoral flexor. En las bases de datos se encontraron 12.104 artículos con el término músculos isquiotibiales, cinco con el término músculos del compartimento femoral posterior y uno con el término músculos del compartimento femoral flexor. En los recursos digitales de anatomía el 50 % utilizaba el término músculos isquiotibiales, el 37,5 % el término músculos del compartimento femoral posterior y el 12,5 % músculos del compartimento femoral flexor. En conclusión, el uso del término músculos isquiotibiales supera ampliamente al uso de los términos indicados por Terminologia Anatomica Internacional. Adicionalmente, este término es anatómicamente descriptivo y unívoco. Al respecto, parece apropiado valorar la incorporación del término músculos isquiotibiales en Terminologia Anatomica Internacional
The Long Non-Coding RNA MALAT1 Modulates NR4A1 Expression through a Downstream Regulatory Element in Specific Cancer Cell Types
Get PDFPublisher Copyright: © 2024 by the authors.Long non-coding RNAs (lncRNAs) have been shown to modulate gene expression and are involved in the initiation and progression of various cancer types. Despite the wealth of studies describing transcriptome changes upon lncRNA knockdown, there is limited information describing lncRNA-mediated effects on regulatory elements (REs) modulating gene expression. In this study, we investigated how the metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) lncRNA regulates primary target genes using time-resolved MALAT1 knockdown followed by parallel RNA-seq and ATAC-seq assays. The results revealed that MALAT1 primarily regulates specific protein-coding genes and a substantial decrease in the accessibility downstream of the NR4A1 gene that was associated with a decreased NR4A1 expression. Moreover, the presence of an NR4A1-downstream RE was demonstrated by CRISPR-i assays to define a functional MALAT1/NR4A1 axis. By analyzing TCGA data, we identified a positive correlation between NR4A1 expression and NR4A1-downstream RE accessibility in breast cancer but not in pancreatic cancer. Accordingly, this regulatory mechanism was experimentally validated in breast cancer cells (MCF7) but not in pancreatic duct epithelial carcinoma (PANC1) cells. Therefore, our results demonstrated that MALAT1 is involved in a molecular mechanism that fine-tunes NR4A1 expression by modulating the accessibility of a downstream RE in a cell type-specific manner
The Role of Social Networks in Eating Behavior Disorders among Adolescents
Get PDFPublisher Copyright: © 2024, Editorial Ciencias Medicas. All rights reserved.Introduction: In addition to facilitating communication among people, social networks provide information and entertainment media. Although this can be favorable, it also has important consequences on the development of anorexia nervosa in adolescents, since such is a stage that involves psychological, physical and social changes. Objective: To find out how social networks have impacted on the development of anorexia nervosa in adolescents with the purpose of maintaining beauty stereotypes and how, from the public health point of view, this problem could be intervened. Methods: An integrative review study of original articles was carried out, using mixed methodology and review. The search strategy was to look up in the SciELO, Scopus (ScienceDirect), Dialnet, WOS, CINAHL and MEDLINE/PubMed databases, using the descriptors red social [social network], adolescente [adolescent], salud mental [mental health], trastornos de alimentación e ingestión de alimentos [eating and food ingestion disorders] and anorexia nerviosa [anorexia nervosa], combined with the Booleans AND, NOT and OR; and to answer the question What influence have social networks had on the development of anorexia nervosa in adolescents? Articles published from 2017-2023 in Spanish, English and Portuguese language were included, which also highlighted studied constructs; while articles unrelated to the research objective and without defined constructs were excluded. The PRISMA guide was adopted to evaluate and synthesize the 14 analyzed articles. Conclusion: The evidence supports the relationship between social networks and anorexia nervosa; therefore; it is important to implement prevention strategies that address recommendations on the use of social networks and mental health in adolescents
Exact oscillations and chaos on a non-Abelian coil
No full textPublisher Copyright: © 2024 The Author(s)We construct new exact solutions of the Georgi-Glashow model in 3+1 dimensions. These configurations are periodic in time but lead to a stationary energy density and no energy flux. Nevertheless, they possess a characteristic frequency which manifests itself through non-trivial resonances on test fields. This allows us to interpret them as non-Abelian self sustained coils. We show that for larger energies a transition to chaotic behavior takes place, which we characterize by Poincaré sections, Fourier spectra and exponential growth of the geodesic deviation in an effective Jacobi metric, the latter triggered by parametric resonances
Current Research on Molecular Biomarkers for Colorectal Cancer in Stool Samples
No full textPublisher Copyright: © 2023 by the authors.Colorectal cancer (CRC) is one of the most diagnosed cancers worldwide, with a high incidence and mortality rate when diagnosed late. Currently, the methods used in healthcare to diagnose CRC are the fecal occult blood test, flexible sigmoidoscopy, and colonoscopy. However, the lack of sensitivity and specificity and low population adherence are driving the need to implement other technologies that can identify biomarkers that not only help with early CRC detection but allow for the selection of more personalized treatment options. In this regard, the implementation of omics technologies, which can screen large pools of biological molecules, coupled with molecular validation, stands out as a promising tool for the discovery of new biomarkers from biopsied tissues or body fluids. This review delves into the current state of the art in the identification of novel CRC biomarkers that can distinguish cancerous tissue, specifically from fecal samples, as this could be the least invasive approach
Estimación del peso en caballos (Equus caballus) fina sangre inglés de carrera y pura raza chilena mediante cinta métrica específica y ecuación matemática
No full textCriogeles de alginato como plantilla para la preparación de oleogeles comestibles
No full textPublisher Copyright: © 2024 by the authors.A high consumption of solid fats is linked to increased inflammation and a risk of cardiovascular diseases. Hence, in recent years, there has been increasing interest in the development of oleogels as a fat substitute in food products. Oleogels are edible gels that contain a large amount of liquid oils entrapped in a 3D network and that can potentially be applied to spreads, bakery goods, meat, and dairy products in order to lower their saturated fat content while maintaining a desirable food texture and mouthfeel. In this work, alginate cryogels were studied as templates for three different edible oils in the process of oleogel formation. Two different freezing regimes to obtain cryogels were employed in order to evaluate better the textural and morphological capabilities of cryogels to adsorb and retain edible oils. It was shown that rapid freezing in liquid nitrogen produces alginate cryogels with a lower density, higher porosity, and a greater ability to adsorb the tested oils. The highest uptake and holding oil capacity was achieved for olive oil, which reached a value of 792% and 82%, respectively. The best chewiness was found for an oleogel containing olive oil, whereas oleogels with the other two tested oils showed better springiness. Hence, the results presented in this work demonstrated that alginate-based cryogels can be effectively used as templates for oleogels and potentially find applications in the food industry