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Caracterización taxonómica, genética y de patogenicidad de Anisakis presentes en Chile
Get PDFLos nemátodos del género Anisakis son parásitos zoonóticos con un ciclo de vida complejo, donde intervienen múltiples especies marinas en el desarrollo de cuatro estadios larvales. Lo anterior ha permitido el reporte de sus larvas en más de 200 especies de peces y 25 cefalópodos a nivel global. Dentro de las nueve especies descritas para el género, destacan A. simplex sensu stricto (s. s.), y A. pegreffii, por sus reportes como agentes etiológicos de una zoonosis conocida como anisakiasis. Pese el potencial patógeno de sus larvas, el conocimiento de la biodiversidad de Anisakis sp., Chile aún resulta escasa. Por tanto, esta tesis doctoral, busca identificar y caracterizar las larvas de Anisakis spp. en diferentes hospedadores a través de técnicas moleculares, para determinar su diversidad y el potencial patógeno que rigen su viabilidad, y alergenicidad asociada a humanos, mediante ensayos que replican técnicas de conservación y manipulación de alimentos. En base a lo planteado, el primer objetivo busca conocer la diversidad del género Anisakis en la costa chilena, para ello, se recolectaron larvas de Anisakis spp. en la cavidad abdominal de seis especies de importancia comercial, procedentes de diversos terminales pesqueros del país. La identificación de las larvas se obtuvo mediante la caracterización morfométrica de 4 caracteres y análisis genéticos de la región mitocondrial (COX2) y nuclear (ITS). Ambos análisis concuerdan la identificación de A. pegreffii para todos los hospedadores, y con una escasa variabilidad genética. El segundo objetivo fue conocer el impacto de diferentes temperaturas (5°C, 60°C y 70°C) y acidez (pH4) en la viabilidad y expresión genética de genes asociados la trehalosa, disacárido asociado a la protección contra estrés oxidativo, térmico y acidez. Para ello se colectaron las larvas de hospedadores Trachurus murphyi (Jurel), Merluccius gayi (Merluza) y Thyrsites atun (Sierra). Los resultados evidenciaron una mayor viabilidad en las larvas expuestas al tratamiento de refrigeración. Así mismo, se detectó altos valores expresión de la trehalosa para todos los tratamientos, siendo las larvas provenientes de sierra y jurel las que presentaron una mayor expresión, posiblemente como consecuencia de la gran cantidad de ácidos grasos totales y polinsaturados, respectivamente. El tercer objetivo, buscó evaluar la patogenidad de los nemátodos bajo cambios de temperatura y acidez anteriormente descritas, utilizando los genes que codifican alérgenos asociados con la respuesta inmune humana a la anisakiasis. Se evidenció una elevada expresión genética a bajas temperaturas (5°C) en larvas provenientes de sierra. Esta investigación proporciona información sobre la expresión alergénica de las larvas de A. pegreffii ante tratamientos que simulan las condiciones de preparación cotidiana de estos peces por la población, abriendo puertas a estudios epidemiológicos, y sumando conocimientos sobre los mecanismos moleculares involucrados en la patogenicidad de A. pegreffii, a través de la interacción hospedador parásito
It's not just the CROWN that makes the king, results in aortic position
Get PDFIntroduction: The use of biological valves in the aortic position has become more liberal in recent years due to improvements in prostheses and the possibility of performing valve-in-valve procedures, thus avoiding anticoagulation.
Methods: We retrospectively evaluated 246 adults in whom the Crown PRTTM biological valve was used in the aortic position, including elective and emergency cases, isolated and combined surgeries (CS). We also evaluated mortality at 1, 3, and 5 years of follow-up.
Results: In this study, CS involved 94 patients (38%), while 39 patients (16%) underwent urgent or emergency procedures, which included cases of aortic dissection and endocarditis. Approximately 69% of the patients received a valve more significant than 21 mm. A minimally invasive surgical approach was employed in 42 patients (17%). The in-hospital mortality for the entire patient population was 3.6% (n = 9), with isolated aortic valve replacement (AVR) accounting for 3.3% (n = 5) and CS for another 4.3% (n = 4). The mortality for isolated AVR and CS in elective situations was n = 2 (1.3%) and n = 1 (1.1%), respectively. During the follow-up period, only seven patients required reoperation, with two patients (0.8%) experiencing structural valve deterioration and five other patients (2.1%) requiring reoperation due to prosthetic valve endocarditis.
Conclusion: The use of the Crown valve in the aortic position appears to be safe regarding postoperative morbidity and mortality. Further studies are necessary to assess its applicability in younger patients and predict its performance in the event of a valve-in-valve procedure
Innovation in strategic planning through fuzzy methodologies: a study of the industrial context of Bogota, Colombia during COVID-19
No full textThe paper analyses the strategic planning in the industrial context of Bogota, Colombia during COVID-19. Because of the different perspectives and subjectivity of the topic, the objective is to use an innovative methodology based on different multi-criteria decision-making (MCDM) characteristics and fuzzy logic to analyse the problem. The methodologies used were the Bonferroni ordered weighted average (OWA) operator and the Pitchat algorithm. The study was based on five sectors with seven strategic scopes. Among the main results was possible to visualise that all the sectors find the most important scope in marketing and the less important scope in Formalisation. Finally, some specific analyses of the results for each sector are presented to visualise how the scopes of the strategic planning can change depending on the sector
COVID-19 patient satisfaction and associated factors in telemedicine and hybrid system
Get PDFBackground: The quality assessment of the home-based isolation and care program (HBIC) relies heavily on patient satisfaction and length of stay. COVID-19 patients who were isolated and received HBIC were monitored through telephone consultations (TC), in-person TC visits, and a self-reporting application. By evaluating patient satisfaction and length of stay in HBIC, healthcare providers could gauge the effectiveness and efficiency of the HBIC program.
Methods: A cross-sectional study design enrolled 444 HBIC patients who answered a structured questionnaire. A binary logistic regression model assessed the association between independent variables and patient satisfaction. The length of stay in HBIC was analyzed using Cox regression analysis. The data collection started on April (1–30), 2022, in Addis Ababa, Ethiopia.
Results: The median age was 34, and 247 (55.6%) were females. A greater proportion (313, 70.5%) of the participants had high satisfaction. Higher frequency of calls (>3 calls) (AOR = 2.827, 95% CI = 1.798, 4.443, p = 0.000) and those who were symptomatic (AOR = 2.001, 95% CI = 1.289, 3.106, p = 0.002) were found to be significant factors for high user satisfaction. Higher frequency of calls (>3 calls) (AHR = 0.537, 95% CI = 0.415, 0.696, p = 0.000) and more in-person visits (>1 visit) (AHR = 0.495, 95% CI = 0.322, 0.762, p = 0.001) had greater chances to reduce the length of stay in the COVID-19 HBIC.
Conclusion: 70.5% of the participants had high satisfaction with the system, and frequent phone call follow-ups on patients’ clinical status can significantly improve their satisfaction and length of recovery. An in-person visit is also an invaluable factor in a patient’s recovery
Mapper of the IGM spin temperature: Instrument overview
Get PDFThe observation of the global 21 cm signal produced by neutral hydrogen gas in the intergalactic medium (IGM) during the Dark Ages, Cosmic Dawn, and Epoch of Reionization requires measurements with extremely well-calibrated wideband radiometers. We describe the design and characterization of the Mapper of the IGM Spin Temperature (MIST), which is a new ground-based, single-antenna, global 21 cm experiment. The design of MIST was guided by the objectives of avoiding systematics from an antenna ground plane and cables around the antenna, as well as maximizing the instrument’s on-sky efficiency and portability for operations at remote sites. We have built two MIST instruments, which observe in the range 25–105 MHz. For the 21 cm signal, this frequency range approximately corresponds to redshifts 55.5 > z > 12.5, encompassing the Dark Ages and Cosmic Dawn. The MIST antenna is a horizontal blade dipole of 2.42 m in length, 60 cm in width, and 52 cm in height above the ground. This antenna operates without a metal ground plane. The instruments run on 12 V batteries and have a maximum power consumption of 17 W. The batteries and electronics are contained in a single receiver box located under the antenna. We present the characterization of the instruments using electromagnetic simulations and lab measurements. We also show sample sky measurements from recent observations at remote sites in California, Nevada, and the Canadian High Arctic. These measurements indicate that the instruments perform as expected. Detailed analyses of the sky measurements are left for future work
TOI-663: A newly discovered multi-planet system with three transiting mini-Neptunes orbiting an early M star
Get PDFWe present the detection of three exoplanets orbiting the early M dwarf TOI-663 (TIC 54962195; V = 13.7 mag, J = 10.4 mag, R★ = 0.512 ± 0.015 R⊙, M★ = 0.514 ± 0.012 M⊙, d = 64 pc). TOI-663 b, c, and d, with respective radii of 2.27 ± 0.10 R⊕, 2.26 ± 0.10 R⊕, and 1.92 ± 0.13 R⊕ and masses of 4.45 ± 0.65 M⊕, 3.65 ± 0.97 M⊕, and <5.2 M⊕ at 99%, are located just above the radius valley that separates rocky and volatile-rich exoplanets. The planet candidates are identified in two TESS sectors and are validated with ground-based photometric follow-up, precise radial-velocity measurements, and high-resolution imaging. We used the software package juliet to jointly model the photometric and radial-velocity datasets, with Gaussian processes applied to correct for systematics. The three planets discovered in the TOI-663 system are low-mass mini-Neptunes with radii significantly larger than those of rocky analogs, implying that volatiles, such as water, must predominate. In addition to this internal structure analysis, we also performed a dynamical analysis that confirmed the stability of the system. The three exoplanets in the TOI-663 system, similarly to other sub-Neptunes orbiting M dwarfs, have been found to have lower densities than planets of similar sizes orbiting stars of different spectral types
Facebook como ferramenta discursiva do movimento feminista chileno de 2018
No full textIntroducción: El presente estudio se enfoca en los contenidos discursivos construidos por estudiantes autoconvocadas en páginas de Facebook durante el movimiento estudiantil feminista 2018 en tres universidades de Concepción, Chile.
Metodología: La investigación se llevó a cabo entre el 1 de mayo y el 30 de junio del 2018 y se aplicó un muestreo no probabilístico intencional a texto e imágenes. Se seleccionaron las publicaciones que tuvieron mayor cantidad de reacciones en Facebook y se analizaron con un análisis de contenido cualitativo categorial temático.
Resultados: Los resultados muestran que las publicaciones en Facebook buscan desestabilizar un sistema machista y patriarcal y legitimar el poder del movimiento feminista a través de las plataformas digitales.
Discusión: Se evidencia una evolución del activismo tradicional, cumpliendo una función organizativa e informativa.
Conclusiones: El estudio destaca la importancia de la utilización de Facebook como herramienta discursiva en la movilización y construcción de discurso en el movimiento feminista estudiantil de 2018 en Chile
Female participation in management positions in Chilean sports organizations from a gender perspective
Get PDFLas políticas de género en el deporte pretenden impulsar la presencia de mujeres en cargos directivos de organizaciones deportivas. En este contexto, a partir de los datos de tres amplias encuestas realizadas en Chile durante la última década, este artículo tenía dos objetivos: comparar la presencia de mujeres y hombres en los cargos directivos de diferentes tipos de organizaciones deportivas; y analizar las diferencias en el perfil de mujeres y hombres en los puestos de máxima responsabilidad en cada organización. Los resultados mostraron una significativa infrarrepresentación femenina en los cargos directivos y de liderazgo. El estudio constató que las organizaciones deportivas chilenas poseen una segregación vertical, siendo pocas las que cuentan con un equilibrio entre mujeres y hombres, de modo que a pesar de que se hayan incorporado mujeres en las juntas directivas, existe una predominancia masculina. La investigación releva la necesidad de medidas para la aplicación efectiva de políticas de género en el deporte
Sensitivity-improved polarization maps at 40 GHz with CLASS and WMAP data
Get PDFImproved polarization measurements at frequencies below 70 GHz with degree-level angular resolution are crucial for advancing our understanding of the Galactic synchrotron radiation and the potential polarized anomalous microwave emission and ultimately benefiting the detection of primordial B modes. In this study, we present sensitivity-improved 40 GHz polarization maps obtained by combining the CLASS 40 GHz and Wilkinson Microwave Anisotropy Probe (WMAP) Q-band data through a weighted average in the harmonic domain. The decision to include WMAP Q-band data stems from similarities in the bandpasses. Leveraging the accurate large-scale measurements from the WMAP Q band and the high-sensitivity information from the CLASS 40 GHz band at intermediate scales, the noise level at ℓ ä [30, 100] is reduced by a factor of 2–3 in the map space. A pixel domain analysis of the polarized synchrotron spectral index (βs) using the WMAP K band and the combined maps (mean and 16th/84th percentiles across the βs map: -3.08 +0.20-0.20) reveals a stronger preference for spatial variation (probability to exceed for a uniform βs hypothesis smaller than 0.001) than the results obtained using WMAP K and Ka bands (-3.08 +0.14-0.14). The cross-power spectra of the combined maps follow the same trend as other low-frequency data, and validation through simulations indicates negligible bias introduced by the combination method (subpercent level in the power spectra). The products of this work are publicly available on LAMBDA (https://lambda.gsfc.nasa.gov/product/class/class_prod_table.html)
On the effect of short-run and long-run US economic expectations on oil and gold volatilities
No full textThis paper investigates the effect of US Economic expectations on oil and gold volatilities, examining their formation across different time horizons. To this end, we compute expectations using a MS-VAR model from one (short run) to sixteen quarters ahead (long run). Then, we estimate the impact of an expectation shock on oil and gold volatility measures through an impulse response function estimating a VAR model from 1987Q1 to 2022Q1. Our results show that oil volatility is significantly affected by expectations in the short run, while gold volatility is affected by expectations in the long run. In particular, gold and oil volatilities exhibit a decrease following a positive expectation shock