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1.
J Opt Soc Am A Opt Image Sci Vis ; 41(6): B135-B143, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856432

RESUMO

Currently, limitations in modeling the temporal behavior of light propagating through atmospheric turbulence stem from the Taylor's frozen turbulence hypothesis (TFTH). Indeed, under certain conditions it has been reported to be unreliable, often leading to inaccurate predictions. On the other hand, in fluid dynamics an alternative has been validated: the random sweeping hypothesis. Nevertheless, its applicability to optical turbulence has remained unexplored. This work introduces the first, to the best of our knowledge, controlled experiment testing this hypothesis on the spatiotemporal properties from image wander. The existence of two characteristic times is observed, one associated with TFTH decorrelation and a second potentially linked to the sweeping hypothesis.

2.
J Opt Soc Am A Opt Image Sci Vis ; 41(6): PCA1-PCA4, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856437

RESUMO

This joint feature issue in Applied Optics and JOSA A collects articles focused on the topic of propagation through and characterization of atmospheric oceanic phenomena. The papers cover a broad range of topics, many of which were addressed at the 2023 Propagation Through and Characterization of Atmospheric Oceanic Phenomena (pcAOP) Topical Meeting at the Optica Imaging Congress in Boston, Massachusetts, 14-17 August 2023. These papers are supplemented by numerous examples of the current state of research in the field. This is the first pcAOP feature issue, with the intention to produce an issue on this topic every two years.

3.
Appl Opt ; 63(16): PCA1-PCA4, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856626

RESUMO

This joint feature issue in Applied Optics and JOSA A collects articles focused on the topic of propagation through and characterization of atmospheric oceanic phenomena. The papers cover a broad range of topics, many of which were addressed at the 2023 Propagation Through and Characterization of Atmospheric Oceanic Phenomena (pcAOP) Topical Meeting at the Optica Imaging Congress in Boston, Massachusetts, 14-17 August 2023. These papers are supplemented by numerous examples of the current state of research in the field. This is the first pcAOP feature issue, with the intention to produce an issue on this topic every two years.

4.
bioRxiv ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38370632

RESUMO

Failure of septation of the interventricular septum (IVS) is the most common congenital heart defect (CHD), but mechanisms for patterning the IVS are largely unknown. We show that a Tbx5+/Mef2cAHF+ progenitor lineage forms a compartment boundary bisecting the IVS. This coordinated population originates at a first- and second heart field interface, subsequently forming a morphogenetic nexus. Ablation of Tbx5+/Mef2cAHF+ progenitors cause IVS disorganization, right ventricular hypoplasia and mixing of IVS lineages. Reduced dosage of the CHD transcription factor TBX5 disrupts boundary position and integrity, resulting in ventricular septation defects (VSDs) and patterning defects, including Slit2 and Ntn1 misexpression. Reducing NTN1 dosage partly rescues cardiac defects in Tbx5 mutant embryos. Loss of Slit2 or Ntn1 causes VSDs and perturbed septal lineage distributions. Thus, we identify essential cues that direct progenitors to pattern a compartment boundary for proper cardiac septation, revealing new mechanisms for cardiac birth defects.

5.
J Opt Soc Am A Opt Image Sci Vis ; 40(4): OSA1-OSA2, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132989

RESUMO

South American optics research has seen remarkable growth over the past 50 years, with significant contributions in areas such as quantum optics, holography, spectroscopy, nonlinear optics, statistical optics, nanophotonics and integrated photonics. The research has driven economic development in sectors like telecom, biophotonics, biometrics, and agri-sensing. This joint feature issue between JOSA A and JOSA B exhibits cutting-edge optics research from the region, fostering a sense of community and promoting collaboration among researchers.

6.
Medicina (B.Aires) ; 83(1): 65-73, abr. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1430774

RESUMO

Resumen Introducción: En Argentina, los medicamentos de alto costo (MAC) generan una carga económica elevada que deben afrontar las instituciones sanitarias. Sin embargo, no existe a la fecha un estu dio en Argentina que indique la magnitud del real problema de los MAC para la Seguridad Social. El presente trabajo, explora cuál es su impacto económico para una de las principales Obras Sociales del país. Métodos: Se realizó un estudio descriptivo con etapa analítica a partir de datos obtenidos en gerencia de prestaciones, área farmacia y área contable de la institución. Cada medicamento fue clasificado según recomendación de OMS (clasificación Anatómica-Terapéutica- Química-ATC). Los precios fueron consignados en tres valores: nominal al momento de adquisición, actualizado a pesos fin de 2021 utilizando el CER (coeficiente de estabilización de referencia), y en dólares (USD). Se evaluaron 105 324 dispensas de MAC, correspondientes a 258 011 unidades para 10 450 afiliados. Resultados: El gasto total anualizado fue 57 millones de dólares (USD), y por usuario 6220 USD. Solo 1.9% de los afiliados requirieron MAC, aunque el gasto fue del 21.9% de los ingresos (aportes + contribuciones). Los primeros 5 medicamentos que generaron el mayor gasto fueron enzalutamida, bevacizu mab, nivolumab, palbociclib, pembrolizumab. Las enfermedades oncológicas y reumatológicas representaron el 62.8% del gasto. Conclusión: A la luz de los resultados, se deduce que los MAC constituyen un riesgo potencial de desfinanciación del sistema de salud si son abordados de manera atomizada por cada subsector. Los MAC requieren de políticas globales de carácter nacional y/o regional.


Abstract Introduction: In Argentina, high-cost drugs (HCD) induce a high economic burden for all the health system sec tors. However, it does not exist in Argentina any data that indicates the real problem of HCD for Social Security. That is why, the present study explores the economic impact of the HCD for one of the main Institutions of the country. Methods: A descriptive study with an analytical stage was carried out based on data obtained from management, pharmacy and accounting area. Each drug was classified according to WHO recommendation (Anatomical-Therapeutic-Chemical-ATC classification). The prices were expressed in three ways: nominal value at the time of acquisition in local currency, updated using the CER (reference stabilization coefficient), and in US dollars. A total of 105 324 HCD dispensed were evaluated, which corresponded to 258 011 units destined to 10 450 patients. Results: Total annualized spend was US$57 million (US$6220 per patient). Only 1.9% of affiliates required HCD, although those expenses represented 21.9% of the institutions´ total income. The first 5 drugs associated to the highest expenditure were enzalutamide, bevacizumab, nivolumab, palbociclib, pembrolizumab. Oncological and rheumatological diseases represented 62.8% of the HCD costs. Conclusion: Considering the results obtained, it can be deduced that if the HCD problem is approached in a scattered way by each subsec tor, it will become a potential risk for health system defund. The HCD topic requires of global policies at national or even regional level.

7.
J Xenobiot ; 13(1): 90-101, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36810433

RESUMO

In this work, a stability study of dispersions of graphene oxide and graphene oxide functionalized with polyethylene glycol (PEG) in the presence of bovine serum albumin is carried out. First, a structural characterization of these nanomaterials is performed by scanning electron microscopy, atomic force microscopy, and ultraviolet visible spectroscopy, comparing the starting nanomaterials with the nanomaterials in contact with the biological material, i.e., bovine fetal serum. The different experiments were performed at different concentrations of nanomaterial (0.125-0.5 mg/mL) and BSA (0.01-0.04 mg/mL), at different incubation times (5-360 min), with and without PEG, and at different temperatures (25-40 °C). The SEM results show that BSA is adsorbed on the surface of the graphene oxide nanomaterial. Using UV-Vis spectrophotometry, the characteristic absorption peaks of BSA are observed at 210 and 280 nm, corroborating that the protein has been adsorbed. When the time increases, the BSA protein can be detached from the nanomaterial due to a desorption process. The stability of the dispersions is reached at a pH between 7 and 9. The dispersions behave like a Newtonian fluid with viscosity values between 1.1 and 1.5 mPa·s at a temperature range of 25 to 40 °C. The viscosity values decrease as the temperature increases.

8.
Medicina (B Aires) ; 83(1): 65-73, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-36774599

RESUMO

INTRODUCTION: In Argentina, high-cost drugs (HCD) induce a high economic burden for all the health system sectors. However, it does not exist in Argentina any data that indicates the real problem of HCD for Social Security. That is why, the present study explores the economic impact of the HCD for one of the main Institutions of the country. METHODS: A descriptive study with an analytical stage was carried out based on data obtained from management, pharmacy and accounting area. Each drug was classified according to WHO recommendation (Anatomical-Therapeutic-Chemical-ATC classification). The prices were expressed in three ways: nominal value at the time of acquisition in local currency, updated using the CER (reference stabilization coefficient), and in US dollars. A total of 105 324 HCD dispensed were evaluated, which corresponded to 258 011 units destined to 10 450 patients. RESULTS: Total annualized spend was US$57 million (US$6220 per patient). Only 1.9% of affiliates required HCD, although those expenses represented 21.9% of the institutions' total income. The first 5 drugs associated to the highest expenditure were enzalutamide, bevacizumab, nivolumab, palbociclib, pembrolizumab. Oncological and rheumatological diseases represented 62.8% of the HCD costs. CONCLUSION: Considering the results obtained, it can be deduced that if the HCD problem is approached in a scattered way by each subsector, it will become a potential risk for health system defund. The HCD topic requires of global policies at national or even regional level.


Introducción: En Argentina, los medicamentos de alto costo (MAC) generan una carga económica elevada que deben afrontar las instituciones sanitarias. Sin embargo, no existe a la fecha un estudio en Argentina que indique la magnitud del real problema de los MAC para la Seguridad Social. El presente trabajo, explora cuál es su impacto económico para una de las principales Obras Sociales del país. Métodos: Se realizó un estudio descriptivo con etapa analítica a partir de datos obtenidos en gerencia de prestaciones, área farmacia y área contable de la institución. Cada medicamento fue clasificado según recomendación de OMS (clasificación Anatómica-Terapéutica- Química-ATC). Los precios fueron consignados en tres valores: nominal al momento de adquisición, actualizado a pesos fin de 2021 utilizando el CER (coeficiente de estabilización de referencia), y en dólares (USD). Se evaluaron 105 324 dispensas de MAC, correspondientes a 258 011 unidades para 10 450 afiliados. Resultados: El gasto total anualizado fue 57 millones de dólares (USD), y por usuario 6220 USD. Solo 1.9% de los afiliados requirieron MAC, aunque el gasto fue del 21.9% de los ingresos (aportes + contribuciones). Los primeros 5 medicamentos que generaron el mayor gasto fueron enzalutamida, bevacizumab, nivolumab, palbociclib, pembrolizumab. Las enfermedades oncológicas y reumatológicas representaron el 62.8% del gasto. Conclusión: A la luz de los resultados, se deduce que los MAC constituyen un riesgo potencial de desfinanciación del sistema de salud si son abordados de manera atomizada por cada subsector. Los MAC requieren de políticas globales de carácter nacional y/o regional.


Assuntos
Gastos em Saúde , Previdência Social , Humanos , Argentina
9.
Sci Rep ; 13(1): 292, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609670

RESUMO

Transition metal dichalcogenide (TMD) semiconductors are two-dimensional materials with great potential for the future of nano-optics and nano-optoelectronics as well as the rich and exciting development of basic research. The influence of an external magnetic field on a TMD monolayer raises a new question: to unveil the behavior of the magneto-polaron resonances (MPRs) associated with the phonon symmetry inherent in the system. It is shown that the renormalized Landau energy levels are modified by the interplay of the long-range Pekar-Fröhlich (PF) and short-range deformation potential (DP) interactions. This leads to a new series of MPRs involving the optical phonons at the center of the Brillouin zone. The coupling of the two Landau levels with the LO and [Formula: see text] optical phonon modes provokes resonant splittings of double avoided-crossing levels giving rise to three excitation branches. This effect appears as bigger energy gaps at the anticrossing points in the renormalized Landau levels. To explore the interplay between the MPRs, the electron-phonon interactions (PF and DP) and the couplings between adjacent Landau levels, a full Green's function treatment for the evaluation of the energy and its life-time broadening is developed. A generalization of the two-level approach is performed for the description of the new MPR branches. The obtained results are a guideline for the magneto-optical experiments in TMDs, where three MPR peaks should be observable.

10.
Rev. ORL (Salamanca) ; 13(3): 211-225, octubre 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-211126

RESUMO

Introducción y objetivo: El incremento de traqueotomías en las unidades de cuidados críticos aumenta notablemente la morbimortalidad en la sala general. Para revertirlo, hemos implementado un programa de seguimiento multidisciplinar basado en la formación, la estandarización de los cuidados y la adopción de nuevas estrategias. Metodología: Estudio de cohorte prospectivo y observacional del seguimiento de 150 pacientes en un hospital universitario de tercer nivel, que carece de unidad de cuidados intermedios. Registramos y analizamos las variables clínicas, epidemiológicas y la evolución tras la aplicación del programa. Resultados: La edad media de los pacientes fue de 61 años, 67% varones y el 42% neurocríticos. 71% con traqueotomía percutánea. La mortalidad general fue del 17% y la de los pacientes con accidente cerebrovascular del 6,3%. Hubo un 8% de reingresos en la unidad de críticos. Detectamos un 23% de complicaciones de escasa gravedad. Se decanuló durante el ingreso a un 43% de pacientes y el 38% volvió a su domicilio, siendo dados de alta un 55% con alimentación oral. El tiempo medio de estancia en la unidad de críticos fue de 34 días y de 70 días la media de ingreso hospitalario. Conclusiones: Este trabajo describe los resultados obtenidos tras aplicar un protocolo de seguimiento multidisciplinar en la sala de hospitalización, del paciente traqueotomizado que procede de las UCC. La finalidad de este seguimiento es mejorar la seguridad de estos pacientes, a fin de disminuir su morbimortalidad. Las aplicación de nuevas estrategias permitirá su evaluación en relación con los datos obtenidos de este estudio. (AU)


Introduction and objective: Increasing the number of tracheostomies in critical care units significantly increases morbimortality in the wards. To reverse this, we have implemented a multidis-ciplinary follow-up program based on training, standardization of care and the adoption of new strategies. Methodology: Prospective and observational cohort study of the follow-up of 150 patients in a third-level university hospital that does not have a step-down unit. We record and analyze the clinical and epide-miological variables and the evolution after the application of the program. Results: The average age was 61 years old, 67 % male, and 41 % neurocritical care patients. Percutaneous tracheostomy in 71 % of all tracheostomies. Global mortality was 17 % and that of patients with stroke was 6.3 %. Readmission to critical care units was 8 %. Low-severity complications were detected in 23 % of patients. The decannulation process was completed during admission in 43 % of patients, 38 % in all discharged from hospital, 55 % of them with oral feeding now of discharge. Average stay in critical care unit was 34 days and hospital length of stay was 70 days. Conclusions: This work describes the results obtained after applying a multidisciplinary follow-up protocol in the wards, of the tracheotomized patient who comes from the critical care units. The purpose of this follow-up is to improve the safety of these patients, to reduce their morbimortality. The application of new strategies will allow their evaluation in relation to the data obtained from this study. (AU)


Assuntos
Humanos , Traqueotomia , Segurança do Paciente , Melhoria de Qualidade , Unidades de Terapia Intensiva , Pacientes , Acidente Vascular Cerebral
11.
Salud Colect ; 17: e3583, 2021 Sep 27.
Artigo em Espanhol | MEDLINE | ID: mdl-34752020

RESUMO

Benzodiazepines and "Z-drugs" (BZD/Z) are overprescribed in many countries. This study evaluates their consumption in a social security sector health insurance provider with national coverage in Argentina. With a descriptive and observational approach, outpatient dispensations of BZD/Zs were analyzed for people over 18 years old from April 2020 to March 2021, disaggregated by sex, age, active ingredient, and half-life. An annual prevalence of use of 11.6% was found among the 431,445 adult affiliates, with higher rates in women and in those over age 60. Overall consumption of BZD/Zs was 77.6 defined daily doses (DDD) per 1000 enrollee-days. The average user received 5.1 annual dispensations and the equivalent of 1.4 DDD for each day of the year. BZD/Zs with long half-life were the most used. We found high levels of BZD/Z consumption and for longer periods than recommended. It is necessary to improve the quality of consumption and reduce the negative impact of inappropriate use of these drugs among treated individuals.


Las benzodiazepinas y los "fármacos Z" (BZD-Z) se prescriben en exceso en muchos países. Este estudio evaluó su consumo en una organización de la seguridad social (obra social) de Argentina de alcance nacional. A partir de un diseño observacional descriptivo se analizó la dispensa ambulatoria de BZD-Z, entre abril 2020 y marzo 2021, a mayores de 18 años; desagregada por sexo, edad, principio activo y vida media. Se encontró una prevalencia anual de uso del 11,6% entre los 431.445 afiliados adultos, con valores más elevados en las mujeres y mayores de 60 años. El consumo global de BZD-Z fue de 77,6 dosis diarias definidas (DDD) cada 1.000 afiliados-día. El usuario promedio recibió 5,1 dispensas anuales y el equivalente a 1,4 DDD por cada día del año. Las BZD-Z más usadas fueron las de vida media larga. El consumo de BZD-Z resultó elevado y más prolongado que lo recomendado. Es necesario mejorar la calidad en el consumo y reducir el impacto negativo del uso inapropiado de estos fármacos entre los individuos tratados.


Assuntos
Benzodiazepinas , Preparações Farmacêuticas , Adolescente , Adulto , Argentina , Benzodiazepinas/efeitos adversos , Feminino , Humanos , Renda , Pessoa de Meia-Idade , Previdência Social
12.
Salud colect ; 17: 3583-3583, 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1365980

RESUMO

RESUMEN Las benzodiazepinas y los "fármacos Z" (BZD-Z) se prescriben en exceso en muchos países. Este estudio evaluó su consumo en una organización de la seguridad social (obra social) de Argentina de alcance nacional. A partir de un diseño observacional descriptivo se analizó la dispensa ambulatoria de BZD-Z, entre abril 2020 y marzo 2021, a mayores de 18 años; desagregada por sexo, edad, principio activo y vida media. Se encontró una prevalencia anual de uso del 11,6% entre los 431.445 afiliados adultos, con valores más elevados en las mujeres y mayores de 60 años. El consumo global de BZD-Z fue de 77,6 dosis diarias definidas (DDD) cada 1.000 afiliados-día. El usuario promedio recibió 5,1 dispensas anuales y el equivalente a 1,4 DDD por cada día del año. Las BZD-Z más usadas fueron las de vida media larga. El consumo de BZD-Z resultó elevado y más prolongado que lo recomendado. Es necesario mejorar la calidad en el consumo y reducir el impacto negativo del uso inapropiado de estos fármacos entre los individuos tratados.


ABSTRACT: Benzodiazepines and "Z-drugs" (BZD/Z) are overprescribed in many countries. This study evaluates their consumption in a social security sector health insurance provider with national coverage in Argentina. With a descriptive and observational approach, outpatient dispensations of BZD/Zs were analyzed for people over 18 years old from April 2020 to March 2021, disaggregated by sex, age, active ingredient, and half-life. An annual prevalence of use of 11.6% was found among the 431,445 adult affiliates, with higher rates in women and in those over age 60. Overall consumption of BZD/Zs was 77.6 defined daily doses (DDD) per 1000 enrollee-days. The average user received 5.1 annual dispensations and the equivalent of 1.4 DDD for each day of the year. BZD/Zs with long half-life were the most used. We found high levels of BZD/Z consumption and for longer periods than recommended. It is necessary to improve the quality of consumption and reduce the negative impact of inappropriate use of these drugs among treated individuals.

13.
Rev. ORL (Salamanca) ; 11(2): 1-9, 2020. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-193766

RESUMO

INTRODUCCIÓN Y OBJETIVOS: El colesteatoma de conducto auditivo externo (CCAE) es un proceso patológico poco frecuente, caracterizado por la invasión de tejido escamoso en un área del canal auditivo, que progresa hasta la destrucción ósea. Debido a la escasez de casos publicados hemos considerado de utilidad esta revisión. MATERIAL Y MÉTODOS: Estudio prospectivo y observacional desde el año 2000, de 18 pacientes diagnosticados clínicamente de CCAE en nuestro servicio de ORL. RESULTADOS: El porcentaje de hombres y mujeres es similar, con una edad media de diagnóstico de 60 años. La localización más frecuente es póstero-inferior y en la mayor parte de casos el origen es primario. La otalgia, la otorrea y la hipoacusia fueron los síntomas principales, siendo menos habitual el prurito y excepcional la debilidad facial. En general el tratamiento es conservador, pero resultó necesario el abordaje quirúrgico en un tercio de pacientes mediante canaloplastia, siguiendo el esquema expuesto, o la mastoidectomía, en función de la extensión de las lesiones. CONCLUSIONES: Aunque desconocemos los mecanismos patogénicos responsables de la formación y desarrollo del CCAE, la inclusión de queratina entre el epitelio y el hueso, con la participación del periostio, parecen ser los desencadenantes del proceso. El diagnóstico es clínico y su extensión determina el empleo de un tratamiento local o quirúrgico, que suele ser resolutivo


INTRODUCTION: External auditory canal cholesteatoma (EACC) is a rare entity characterized by the invasion of squamous tissue in the auditory canal, that progresses to bone destruction. Due to the scarcity of published cases of EACC, we have deemed useful this review. MATERIAL AND METHODS: Prospective and observational study from the year 2000 to the present in 18 patients clinically diagnosed with EACC in our ORL service. RESULTS: The percentage of men and women is similar, with a mean age at diagnosis of 60 years. The most frequently location was postero-inferior, and in most cases, the origin is primary. Otalgia, otorrhea and subjective hearing loss were the main symptoms, being less common the pruritus and exceptional facial weakness. Overall, the treatment is conservative, but it was necessary surgical treatment on one-third of the patients, performing canaloplasty or mastoidectomy, according to the extent of injuries. CONCLUSIONS: Although we do not know the genesis and pathogenic mechanisms responsible of EACC formation and development, the inclusion of keratin between the epithelium and bone, with the participation of the periosteum, seems to be the trigger of this process. The diagnosis is clinical, and its extension determines the use of a local or surgical treatment, which is usually resolutive


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Colesteatoma/diagnóstico por imagem , Colesteatoma/patologia , Procedimentos Cirúrgicos Otológicos/métodos , Colesteatoma/cirurgia , Otopatias/cirurgia , Estudos Prospectivos , Dor de Orelha/etiologia , Endoscopia/métodos , Mastoidectomia
14.
Phys Rev E ; 100(4-1): 042215, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31770914

RESUMO

In this paper, we introduce a model to describe the decay of the number of unobserved ordinal patterns as a function of the time series length in noisy chaotic dynamics. More precisely, we show that a stretched exponential model fits the decay of the number of unobserved ordinal patterns for both discrete and continuous chaotic systems contaminated with observational noise, independently of the noise level and the sampling time. Numerical simulations, obtained from the logistic map and the x coordinate of the Lorenz system, both operating in a totally chaotic dynamics were used as test beds. In addition, we contrast our results with those obtained from pure stochastic dynamics. The fitting parameters, namely, the stretching exponent and the characteristic decay rate, are used to distinguish whether the dynamical nature of the data sequence is stochastic or chaotic. Finally, the analysis of experimental records associated with the hyperchaotic pulsations of an optoelectronic oscillator allows us to illustrate the applicability of the proposed approach in a practical context.

15.
Acta biol. colomb ; 24(2): 202-212, May-ago. 2019. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1010850

RESUMO

RESUMEN La yuca es determinante para la seguridad alimentaria de cientos de millones de personas alrededor del mundo. A pesar de que el principal medio de propagación del cultivo es a través de semilla asexual por estacas (tallos maduros) se ha revelado una relativamente alta diversidad intraespecífica, principalmente en los sistemas de cultivo de manejo tradicional. En esta revisión se documentan algunos estudios realizados sobre la diversidad de la yuca, tanto por marcadores moleculares como morfológicos, centrándose en aquellos realizados en el Amazonas. También se exponen los principales factores que han determinado el aprovechamiento y conservación de esta diversidad, tales como la aparición espontánea de semillas de origen sexual, el sistema de chagras indígenas, la memoria biocultural y la facilidad de intercambio de semilla entre comunidades. Finalmente, se pone de manifiesto que en los sistemas de manejo tradicional la conservación y uso de la diversidad intraespecífica se constituye en un elemento prioritario que se ha perdido en los sistemas de cultivo a gran escala. En los sistemas de manejo tradicional existe un vínculo etnobotánico que pervive e invita a buscar prácticas alternativas que aseguran un mantenimiento de la diversidad, permitiendo una productividad eficiente e incluso se hace un mejor manejo para disminuir los riesgos de incidencia de algunas plagas y enfermedades.


ABSTRACT Cassava is crucial for the food security of hundreds ofmillions of people around the world. Even though the main source of propagation of the crop is through asexual seed by stakes (stems-cuttings) a relative high intraspecific diversity has been identified, mainly in the traditionally managed cultivation systems. Some studies on the diversity of cassava, based on molecular and morphological markers, are documented focusing on those made in the Amazon in this review. Also, the main factors that have determined the use and conservation of this diversity are exposed, such as the spontaneous appearance of seeds of sexual origin, the system of indigenous chagras, the biocultural memory and the ease of seed exchange between communities. From this perspective, it is evident that in traditional management systems the conservation and use of intraspecific diversity is a priority element that has been lost in large-scale farming systems. In traditional management systems, there is an ethnobotanical link that survives and invites us to seek alternative practices that ensure the maintenance of diversity, allowing efficient productivity and even better management to reduce the risk of incidence of some pests and diseases.

16.
Investig. desar. ; 27(1): 234-264, ene.-jun. 2019. tab, graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1090740

RESUMO

RESUMEN Este artículo de reflexión teórica aborda la investigación narrativa como su objeto. Esto obedece a las consideraciones metodológicas de la investigación que originaron esta reflexión. De esta manera, se acude, por una parte, a la bibliografía encontrada sobre tema narrativo, y a la experiencia con los estudiantes con quienes se trabajó. Se encontró que las narraciones permiten penetrar de manera profunda en un contexto familiar que vive un país conflictivo, con grandes escisiones sociales, políticas y económicas. La reflexión se basa en una investigación realizada con los estudiantes del programa de Desarrollo Familiar en la Universidad de Caldas, Manizales (Colombia), y acude a un diálogo con ellos sobre el proceso investigativo, de modo que este artículo se articula en torno a tres fuentes: la investigación de base, la bibliografía sobre narrativas y memoria y el diálogo con los estudiantes.


ABSTRACT This teoric reflection paper deals with narrative research as its main objet, concerning methodological considerations in research which generated this reflection. On one hand the bibliography regarding the subject of narrative is used, on the other hand the experience of the students involve in this study. The findings of this study show that the accounts allow a deep exploration in a family context within a trouble country, with large social, political and economical divisions. The reflection is based on a research carried out with the students of the Desarrollo Familiar program at the Universidad de Caldas, Manizales (Colombia), and they go to a dialogue with them about the investigative process, so this article has three sources: basic research, the bibliography on narratives and memory and the dialogue with students.


Assuntos
Humanos , Estudantes , Família , Narração
17.
Biol Open ; 7(1)2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29183906

RESUMO

How chromatin-remodeling complexes modulate gene networks to control organ-specific properties is not well understood. For example, Baf60c (Smarcd3) encodes a cardiac-enriched subunit of the SWI/SNF-like BAF chromatin complex, but its role in heart development is not fully understood. We found that constitutive loss of Baf60c leads to embryonic cardiac hypoplasia and pronounced cardiac dysfunction. Conditional deletion of Baf60c in cardiomyocytes resulted in postnatal dilated cardiomyopathy with impaired contractile function. Baf60c regulates a gene expression program that includes genes encoding contractile proteins, modulators of sarcomere function, and cardiac metabolic genes. Many of the genes deregulated in Baf60c null embryos are targets of the MEF2/SRF co-factor Myocardin (MYOCD). In a yeast two-hybrid screen, we identified MYOCD as a BAF60c interacting factor; we showed that BAF60c and MYOCD directly and functionally interact. We conclude that Baf60c is essential for coordinating a program of gene expression that regulates the fundamental functional properties of cardiomyocytes.

18.
Opt Lett ; 42(10): 2030-2033, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28504741

RESUMO

We describe, through simulations and experiments, a real-time wavefront acquisition technique using random binary amplitude masks and an iterative phase retrieval algorithm based on the Fresnel propagator. By using a digital micromirror device, it is possible to recover an unknown complex object by illuminating with this set of masks and simultaneously recording the resulting intensity patterns with a high-speed camera, making this technique suitable for dynamic applications.

19.
Phys Rev E ; 96(4-1): 042207, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29347549

RESUMO

We have experimentally quantified the temporal structural diversity from the coordinate fluctuations of a laser beam propagating through isotropic optical turbulence. The main focus here is on the characterization of the long-range correlations in the wandering of a thin Gaussian laser beam over a screen after propagating through a turbulent medium. To fulfill this goal, a laboratory-controlled experiment was conducted in which coordinate fluctuations of the laser beam were recorded at a sufficiently high sampling rate for a wide range of turbulent conditions. Horizontal and vertical displacements of the laser beam centroid were subsequently analyzed by implementing the symbolic technique based on ordinal patterns to estimate the well-known permutation entropy. We show that the permutation entropy estimations at multiple time scales evidence an interplay between different dynamical behaviors. More specifically, a crossover between two different scaling regimes is observed. We confirm a transition from an integrated stochastic process contaminated with electronic noise to a fractional Brownian motion with a Hurst exponent H=5/6 as the sampling time increases. Besides, we are able to quantify, from the estimated entropy, the amount of electronic noise as a function of the turbulence strength. We have also demonstrated that these experimental observations are in very good agreement with numerical simulations of noisy fractional Brownian motions with a well-defined crossover between two different scaling regimes.

20.
Opt Lett ; 41(24): 5696-5699, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27973492

RESUMO

At the foundation of the problem of light propagation through optical turbulence is the classical Obukhov-Kolmogorov theory. It rests in the requirement that the refractive index fluctuations should be homogeneous and isotropic. These, with other necessary assumptions, lead to the very well-known -11/3-power exponent spectrum on the inertial range; although departures have been found, they are usually associated with partially developed turbulence or its intrinsic intermittency. Recently, in optics, the interest in anisotropic fluctuations of the refractive index has gained attention. These studies are mostly theoretical, and reduce anisotropic effects to a dilatation along a coordinate direction in the three-dimensional wavenumber space. Few experimental works exists, but all of them employ simulated turbulence. In this Letter, we describe an experiment to produce anisotropic turbulence under controlled conditions; moreover, we observe anisotropy by studying the spectral power exponent of a temporal series of laser beam wandering.

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