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1.
Int J Mol Sci ; 25(13)2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-39000470

RESUMEN

Agave tequilana stems store fructan polymers, the main carbon source for tequila production. This crop takes six or more years for industrial maturity. In conducive conditions, agave wilt disease increases the incidence of dead plants after the fourth year. Plant susceptibility induced for limited photosynthates for defense is recognized in many crops and is known as "sink-induced loss of resistance". To establish whether A. tequilana is more prone to agave wilt as it ages, because the reduction of water-soluble carbohydrates in roots, as a consequence of greater assembly of highly polymerized fructans, were quantified roots sucrose, fructose, and glucose, as well as fructans in stems of agave plants of different ages. The damage induced by inoculation with Fusarium solani or F. oxysporum in the roots or xylem bundles, respectively, was recorded. As the agave plant accumulated fructans in the stem as the main sink, the amount of these hexoses diminished in the roots of older plants, and root rot severity increased when plants were inoculated with F. solani, as evidence of more susceptibility. This knowledge could help to structure disease management that reduces the dispersion of agave wilt, dead plants, and economic losses at the end of agave's long crop cycle.


Asunto(s)
Agave , Fructanos , Fusarium , Enfermedades de las Plantas , Raíces de Plantas , Agave/microbiología , Agave/metabolismo , Raíces de Plantas/microbiología , Raíces de Plantas/metabolismo , Fructanos/metabolismo , Enfermedades de las Plantas/microbiología , Fusarium/patogenicidad , Hexosas/metabolismo , Tallos de la Planta/microbiología , Tallos de la Planta/metabolismo
2.
IEEE Open J Eng Med Biol ; 5: 467-475, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38899015

RESUMEN

Accurate short- and mid-term blood glucose predictions are crucial for patients with diabetes struggling to maintain healthy glucose levels, as well as for individuals at risk of developing the disease. Consequently, numerous efforts from the scientific community have focused on developing predictive models for glucose levels. This study harnesses physiological data collected from wearable sensors to construct a series of data-driven models based on deep learning approaches. We systematically compare these models to offer insights for practitioners and researchers venturing into glucose prediction using deep learning techniques. Key questions addressed in this work encompass the comparison of various deep learning architectures for this task, determining the optimal set of input variables for accurate glucose prediction, comparing population-wide, fine-tuned, and personalized models, and assessing the impact of an individual's data volume on model performance. Additionally, as part of our outcomes, we introduce a meticulously curated dataset inclusive of data from both healthy individuals and those with diabetes, recorded in free-living conditions. This dataset aims to foster research in this domain and facilitate equitable comparisons among researchers.

3.
Sensors (Basel) ; 23(9)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37177645

RESUMEN

Optimizing the bias modulation of a fiber-optic gyroscope is crucial to improving its precision. In this study, we propose and demonstrate the use of multiple harmonics of sinusoidal modulation as an intermediate alternative to the widely used modulation methods: sinusoidal and square-wave modulation. We show that this alternative integrates the advantages of each modulation method by providing a smooth modulation that produces a clean, spike-free output and a satisfactory signal-to-noise ratio. By using three harmonics of modulation in combination with a high frequency to reduce thermal phase noise, we obtained an angular random walk of 5.2(2)µdeg/h and a bias instability of ∼10µdeg/h. This is the highest performance ever reported for fiber-optic gyroscopes.

4.
Artículo en Inglés | MEDLINE | ID: mdl-36900945

RESUMEN

(1) Background: The CEECCA questionnaire assesses the ability to communicate among individuals with aphasia. It was designed using the NANDA-I and NOC standardised nursing languages (SNLs), reaching high content validity index and representativeness index values. The questionnaire was pilot-tested, demonstrating its feasibility for use by nurses in any healthcare setting. This study aims to identify the psychometric properties of this instrument. (2) Methods: 47 individuals with aphasia were recruited from primary and specialist care facilities. The instrument was tested for construct validity and criterion validity, reliability, internal consistency, and responsiveness. The NANDA-I and NOC SNLs and the Boston test were used for criterion validity testing. (3) Results: five language dimensions explained 78.6% of the total variance. Convergent criterion validity tests showed concordances of up to 94% (Cohen's κ: 0.9; p < 0.001) using the Boston test, concordances of up to 81% using DCs of NANDA-I diagnoses (Cohen's κ: 0.6; p < 0.001), and concordances of up to 96% (Cohen's κ: 0.9; p < 0.001) using NOC indicators. The internal consistency (Cronbach's alpha) was 0.98. Reliability tests revealed test-retest concordances of 76-100% (p < 0.001). (4) Conclusions: the CEECCA is an easy-to-use, valid, and reliable instrument to assess the ability to communicate among individuals with aphasia.


Asunto(s)
Afasia , Humanos , Psicometría , Reproducibilidad de los Resultados , Afasia/diagnóstico , Lenguaje , Encuestas y Cuestionarios
5.
Travel Med Infect Dis ; 52: 102514, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36462747

RESUMEN

OBJECTIVE: To estimate the prevalence of post-vaccination seropositivity against SARS-CoV-2 and identify its predictors in Peruvian Social Health Insurance (EsSalud) personnel in 2021. METHODS: We conducted a cross-sectional study in a representative simple stratified sample of EsSalud workers. We evaluated IgG anti-SARS-CoV-2 antibodies response (seropositivity) by passive (previous infection) and active immunization (vaccination), and epidemiological and occupational variables obtained by direct interview and a data collection form. Descriptive and inferential statistics were used with correction of sample weights adjusted for non-response rate, and crude and adjusted odds ratio (OR) and geometric mean ratio (GMR) with their respective 95% confidence intervals (95%CI) were estimated. RESULTS: We enrolled 1077 subjects. Seropositivity was 67.4% (95%CI: 63.4-71.1). Predictors of seropositivity were age (negative relation; p < 0.001), previous infection (aOR = 11.7; 95%CI: 7.81-17.5), working in COVID-19 area (aOR = 1.47; 95%CI: 1.02-2.11) and time since the second dose. In relation to antibody levels measured by geometric means, there was an association between male sex (aGMR = 0.77; 95%CI: 0.74-0.80), age (negative relation; p < 0.001), previous infection (aGMR = 13.1; 95%CI:4.99-34.40), non-face-to-face/licensed work modality (aGMR = 0.78; 95%CI: 0.73-0.84), being a nursing technician (aGMR = 1.30; 95%CI: 1.20-1.41), working in administrative areas (aGMR = 1.17; 95%CI: 1.10-1.25), diagnostic support (aGMR = 1.07; 95%CI: 1.01-1.15), critical care (aGMR = 0.85; 95%CI: 0.79-0.93), and in a COVID-19 area (aGMR = 1.30; 95%CI: 1.24-1.36) and time since receiving the second dose (negative relation; p < 0.001). CONCLUSIONS: Seropositivity and antibody levels decrease as the time since receiving the second dose increases. Older age and no history of previous infection were associated with lower seropositivity and antibody values. These findings may be useful for sentinel antibody surveillance and the design of booster dose strategies.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Masculino , COVID-19/epidemiología , COVID-19/prevención & control , Estudios Transversales , Perú/epidemiología , Anticuerpos Antivirales
6.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1440950

RESUMEN

Objetivos: Explorar, desde las narrativas de la población de donantes de plasma convaleciente en un ensayo clínico, las experiencias en el proceso de donación de sangre. Métodos: Se realizó un estudio cualitativo con diseño fenomenológico. La investigación se llevó a cabo en un hospital de la seguridad social del Perú aplicándose entrevistas semiestructuradas a profundidad. Resultados: Se entrevistó a once donantes de plasma convaleciente. Se identificó que las principales motivaciones de los donantes fueron tanto el poder contribuir a la investigación nacional como, apoyar a pacientes afectados por la COVID-19. Los principales miedos se centran en el posible riesgo de contagio dentro del hospital. Por otro lado, los donantes resaltaron la atención y acompañamiento del personal de salud en el proceso. Las principales expectativas y sugerencias apuntan hacia una mayor difusión de las campañas de donación de sangre en general, con especial énfasis en el tema de seguridad, la mejora en el tiempo del procedimiento de donación (en el caso de la donación de plasma convaleciente, desde el enrolamiento hasta la extracción de plasma convaleciente) y, la implementación de espacios amigables para incentivar las futuras campañas de donación de sangre en general. Conclusiones: Las experiencias de los donantes de plasma convaleciente fueron positivas. Sin embargo, aún hay mejoras que realizar a nivel de procesos e infraestructuras para asegurar campañas exitosas de donación de sangre futuras.


Objectives: To know and explore from convalescent plasma donators' voices the experience in the blood donation process at a social security hospital. Methods: Qualitative study with a phenomenological design. The investigation was carried out in 01 hospitals of the social security of Peru. Semi-structured interviews were carried out. Results: Eleven donors of convalescent plasma were interviewed. The main motivations for donating were being able to contribute to national research and supporting patients affected by COVID-19. Fears focus on the possible risk of contagion within the hospital. Donors emphasised the attention and support of health personnel alongside the donation procedure. The main expectations and suggestions point towards greater dissemination of donation campaigns with special emphasis on safety. Likewise, an improvement in the time of the donation procedure (from enrolment to the extraction of convalescent plasma), and the implementation of friendly spaces to encourage future blood donation campaigns were highlighted. Conclusions: The experience of the convalescent plasma donors was positive. However, improvements must be made in terms of processes and infrastructure to ensure future successful blood donation campaigns.

7.
AoB Plants ; 14(3): plac027, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35782336

RESUMEN

Agave (Agave tequilana var. azul) is considered a crop with low genetic diversity because it has been propagated vegetatively for centuries for commercial purposes, and consequently, it could be equally susceptible to pests and diseases. However, the present study employs plant material derived from field-grown plants exhibiting phenotypic variability in susceptibility to agave wilt. The offshoots from rhizomes of these plants were reproduced in vitro and classified as potentially resistant or susceptible. Amplified fragment length polymorphism analysis confirmed wide genetic differences among individuals, but these differences were not correlated with the observed phenotypic variability in resistance. Propagated plantlets were inoculated with Fusarium solani in two time-lapse confrontations for 72 h and 30 days. The early biochemical response showed statistically superior levels in the accumulation of shikimic acid, phenolic compounds, and chitinase activity in potentially resistant plantlets. There was an inverse correlation of these early biochemical responses and salicylic acid and the incidence of diseased root cells in isogenic plantlets in the 30-day confrontation with F. solani, suggesting that these activities and accumulation of molecules were primordial in the defence against this pathogen.

8.
Nat Phys ; 18(10): 1240-1247, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37396880

RESUMEN

Wave-like beating of eukaryotic cilia and flagella-threadlike protrusions found in many cells and microorganisms-is a classic example of spontaneous mechanical oscillations in biology. This type of self-organized active matter raises the question of the coordination mechanism between molecular motor activity and cytoskeletal filament bending. Here we show that in the presence of myosin motors, polymerizing actin filaments self-assemble into polar bundles that exhibit wave-like beating. Importantly, filament beating is associated with myosin density waves initiated at twice the frequency of the actin-bending waves. A theoretical description based on curvature control of motor binding to the filaments and of motor activity explains our observations in a regime of high internal friction. Overall, our results indicate that the binding of myosin to actin depends on the actin bundle shape, providing a feedback mechanism between the myosin activity and filament deformations for the self-organization of large motor filament assemblies.

9.
Rev Sci Instrum ; 86(7): 073110, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26233359

RESUMEN

We developed a high-power laser system at a wavelength of 399 nm for laser cooling of ytterbium atoms with ultraviolet laser diodes. The system is composed of an external cavity laser diode providing frequency stabilized output at a power of 40 mW and another laser diode for amplifying the laser power up to 220 mW by injection locking. The systematic method for optimization of our injection locking can also be applied to high power light sources at any other wavelengths. Our system does not depend on complex nonlinear frequency-doubling and can be made compact, which will be useful for providing light sources for laser cooling experiments including transportable optical lattice clocks.

10.
Rev. Fac. Odontol. Univ. Antioq ; 22(1): 23-32, dic. 2010. ilus, tab, graf
Artículo en Español | LILACS | ID: lil-575816

RESUMEN

Introducción: el objetivo de este estudio fue investigar la presencia de la variable canal mandibular bífido (VCMB), por sujeto y por lado. Se distribuyó por tipo, según la clasificación de Naitoh, Hiraiwa, Aimiya y Ariji, agregándose el tipo canal triple. Se asoció con el género y se comparó la observación de la VCMB entre la vista panorámica y los cortes sagitales y coronales del sistema Cone Beam. Métodos: se analizó una muestra aleatoria de 84 sujetos (52 mujeres, 32 hombres), entre doce y ochenta años, conducido entre los años 2008 y 2009 en el Centro Sistemas Radiológicos Máxilo Faciales de Santiago de Chile. Se efectuaron adquisiciones volumétricas por medio de TC, sistema Cone Beam, utilizando un equipo Siemens Sirona, modelo Galileos Comfort. Se clasificaron los pacientes por edad y sexo. Se realizó un análisis cualitativo y cuantitativo marcando recorrido de ambos conductos dentarios inferiores. Se clasifica la VCMB de acuerdo con la propuesta de los autores, Naitoh, Hiraiwa, Aimiya y Ariji y canal triple. Se observó y comparó la presencia de la VCMB entre vista panorámica y cortes sagitales y coronales. Resultados: el 69% de la muestra considerada en el estudio presentó al menos una variación en el trayecto del conducto dentario inferior. La variable del recorrido del conducto dentario que presentó mayor frecuencia fue la clasificada como prolongación anterior con confluencia (39,28%) y en segundo lugar la variable clasificada como canal retromolar (23,80%). Se encontró una diferencia estadísticamente significativa al comparar los cortes sagitales y coronales del estudio volumétrico mediante tomografía de alta resolución con relación a la reconstrucción panorámica, lo que sugiere que las imágenes panorámicas son insuficientes para la investigación de variables en el recorrido del conducto dentario inferior.


Introduction: the purpose of this study was to evaluate the presence of a bifid mandibular canal variable (BMCV), by subject and by side. It was distributed by type, as classified by Naitoh, Hiraiwa, Aimiya and Ariji, adding the triple canal type. It was also associated with gender and the BMCV observation was compared with the panoramic view and the sagittal and coronal Cone Beam System. Methods: a random sample of 84 subjects (52 women, 32 men) between 12 and 80 years of age was analyzed; it was conducted between 2008 and 2009 at the Maxillo Facial Radiology Systems Center of Santiago de Chile. Volumetric acquisitions were made by CT, Cone Beam System, using Siemens Sirona equipment, model Galileos Comfort. Patients were classified by age and gender. We performed a qualitative and quantitative analysis both marking the path of the mandibular canal; BMCV was classified according to the classification of Naitoh, Hiraiwa, Aimiya and Ariji. The presence of BMCV was observed and compared between panoramic, and the sagittal and coronal slices. Results: 69% of the sample of the study showed at least one variation in the trajectory of the inferior dental canal. The variable of the trajectory of the dental canal which showed the highest frequency was the one classified as anterior elongation with confluence (39.28%) and, in second place the variable known as retromolar canal (23.80%). There was a statistical significant difference when the sagittal slices were compared with the coronal slices of the volumetric study through high resolution tomography in relation with the panoramic reconstruction, which suggests that the panoramic images are not sufficient to look for variables in the trajectory of the inferior dental canal. As it relates to gender, it was found that there was a statistically significant difference (p = 0.02) for the variable classified as lingual canal.


Asunto(s)
Humanos , Tomografía Computarizada de Haz Cónico , Radiografía Panorámica
12.
Can J Microbiol ; 55(7): 887-94, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19767862

RESUMEN

Mycosphaerella fijiensis causes black leaf streak disease in banana and plantain. This fungus is usually attacked by reactive oxygen species secreted by the plant or during exposure to fungicide, however, little is known about the antioxidant response of the fungus. In this study, mycelia were observed to totally decompose 30 mmol/L of hydrogen peroxide (H2O2) within 120 min, liberating oxygen bubbles, and also to survive in concentrations as high as 100 mmol/L H2O2. The oxidative stress responses to H2O2, paraquat, and hydroquinone were characterized in terms of the activities of catalase and superoxide dismutase (SOD). Two active catalase bands were seen in native PAGE induced by H2O2. Band I had monofunctional activity and band II had bifunctional catalase-peroxidase activity. Two isozymes of SOD, distinguishable by their cyanide sensitivity, were found; CuZnSOD was the main one. The combination of H2O2 and 3-aminotriazole reduced the accumulation of biomass up to 40% compared with exposure to H2O2 alone, suggesting that catalase is important for the rapid decomposition of H2O2 and has a direct bearing on cell viability. The results also suggest that the superoxide anion formed through the redox of paraquat and hydroquinone has a greater effect than H2O2 on the cellular viability of M. fijiensis.


Asunto(s)
Ascomicetos/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Musa/microbiología , Estrés Oxidativo , Paraquat/farmacología , Enfermedades de las Plantas/microbiología , Ascomicetos/enzimología , Ascomicetos/metabolismo , Proteínas Fúngicas/metabolismo , Superóxido Dismutasa/metabolismo , Superóxidos/metabolismo
14.
Diagnóstico (Perú) ; 47(4): 160-162, oct.-dic. 2008.
Artículo en Español | LILACS, LIPECS | ID: lil-515235
15.
Acta pediatr. esp ; 61(11): 629-632, dic. 2003. ilus, tab
Artículo en Es | IBECS | ID: ibc-28580

RESUMEN

Objetivo: Estudio sobre consejos de higiene, con respecto a la postura y la prevención del dolor de espalda, impartidos a niños en el ámbito escolar desde la Asistencia Primaria. Metodología: Durante dos años, se efectuaron clases dirigidas a escolares del último curso de primer grado en las tres escuelas públicas pertenecientes al Área Básica de Salud. En estos escolares se realizó un estudio descriptivo de tipo observacional, seleccionando una muestra de 37 alumnos escogida aleatoriamente, según el método aleatorizado simple, que se llevó a cabo distribuyendo una encuesta previamente validada, que constaba de 7 ítems con preguntas sobre higiene postural, dolor de espalda y práctica de ejercicio físico. A 21 de estos alumnos se les distribuyó la encuesta antes de efectuar la clase de educación sanitaria, y a otros 16 se les distribuyó después de haber realizado la clase; posteriormente, se les pusieron tres ejemplos prácticos para ver sí los consejos impartidos se habían asimilado o no: recoger un objeto del suelo, coger un objeto puesto en lo alto de una estantería y sentarse en la mesa para escribir. Resultados: Estas clases se dirigieron a un total de 108 escolares que asistían al último curso de primer grado, en las tres escuelas públicas del Área Básica de Salud, durante los dos últimos años y también a los padres en el propio Centro de Salud, con muy buena aceptación por parte de todos, manifestando quedar satisfechos el 98 por ciento de los entrevistados. Por otra parte, al menos uno de cada dos niños manifestó haber tenido, al menos una vez en su vida, dolor de espalda. La distribución por sexos era del 51 por ciento de niños y del 49 por ciento de niñas. Respecto a los niños a los que se les distribuyó la encuesta antes de la clase, sólo el 1 por ciento consideraba que el dolor de espalda era debido a mala higiene de la postura, el 60 por ciento de ellos consideró que era mejor dormir en cama blanda, y sólo el 19 por ciento manifestó no efectuar habitualmente ejercicio físico. Todos los niños que contestaron la encuesta después de recibir la clase de educación sanitaria consideraban que el dolor de espalda era debido a una mala postura (excepto uno que lo atribuía también a enfermedad), el 63 por ciento estimo que era mejor dormir en cama dura y el 18 por ciento estimó que no hacían ejercicio regularmente. Después de la educación sanitaria, el 99 por ciento de ellos sabía que lo mejor para coger un objeto del suelo era hacerlo agachado en cuclillas, el 81 por ciento sabía que no podía estirar demasiado la espalda para coger un objeto que estuviera alto y que lo mejor era subirse a una banqueta, y el 99 por ciento había aprendido a sentarse correctamente en la mesa, con la espalda recostada en el respaldo de la silla. Conclusiones: La valoración de la educación sanitaria ha sido muy buena tanto por parte de los escolares, como de los padres y los profesores. Parece que, al menos a corto plazo, se asimilaron bien los cambios de conocimiento y actitud para prevenir el dolor de espalda. Se ha considerado, por tanto, que el dar consejos sobre higiene postural y práctica de ejercicio físico puede resultar una medida muy eficaz en la prevención del dolor de espalda (AU)


Asunto(s)
Femenino , Masculino , Niño , Humanos , Dolor de Espalda/prevención & control , Prevención Primaria/métodos , Educación en Salud , Atención Primaria de Salud , Postura , Epidemiología Descriptiva , Muestreo Aleatorio Simple , Ejercicio Físico
17.
Rev. sanid. mil ; 47(5): 173-4, sept.-oct. 1993.
Artículo en Español | LILACS | ID: lil-134959

RESUMEN

Artículo de revisión de los tratamientos usados por diferentes investigadores en grupos de 33, 20, 43 y 36 pacientes menopáusicas respectivamente, en quienes en algunos casos se prescribió un progestágeno de depósito intramuscular, acetato de medroxiprogesterona AMPD, cada 30 y 60 días. Otros investigadores han usado estrógenos conjugados solos y, otros más, los han prescrito combinados con el progestágeno. Todos los autores llegaron a la misma conclusión, que el AMPD es de utilidad en los trastornos del climaterio y evita la osteoporosis. Consideran que es una buena opción cuando existen contraindicaciones para la terapéutica estrogénica


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Progesterona/administración & dosificación , Climaterio/efectos de los fármacos , Medroxiprogesterona/administración & dosificación , Progesterona/uso terapéutico , Osteoporosis Posmenopáusica/prevención & control , Osteoporosis Posmenopáusica/tratamiento farmacológico , Inyecciones Intramusculares
19.
s.l; Programa de Apoyo y Extensión en Salud Materno Infantil; 1985. 21 p.
Monografía en Español | LILACS | ID: lil-70924
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