74 research outputs found
Cuando Cuba entró en París : retombées barthesianas en la crítica literaria de Severo Sarduy
En el presente artículo se exploran los usos barthesianos de la crítica literaria de Severo Sarduy. En primer lugar, analizamos de qué manera la lectura estructuralista-telquelista realizada por Sarduy sobre las obras de Góngora y Lezama Lima le permitió elaborar el concepto de neobarroco como rasgo identitario de la cultura cubana. En segundo lugar, vemos cómo a través de la práctica del "habla indirecta" barthesiana Sarduy acaba constituyendo una crítica literaria en la que Cuba se afirma y se cuestiona a la vez.En el present article s'exploren els usos barthesianos de la crítica literària de Sever Sarduy. En primer lloc, analitzem de quina manera la lectura estructuralista-telquelista realitzada per Sarduy sobre les obres de Góngora i Lezama Lima li va permetre elaborar el concepte de neobarroc com a tret identitari de la cultura cubana. En segon lloc, veiem com a través de la pràctica del "parla indirecta" barthesiana Sarduy acaba constituint una crítica literària en què Cuba s'afirma i es qüestiona alhora.This article explores the uses of Roland Barthes in Severo Sarduy's literary criticism. First, we analyse how the structuralist-telquelist reading operated by Sarduy on the works of Luis de Góngora and José Lezama Lima allowed him to develop the concept of neo-baroque as an identifying feature of Cuban culture. Secondly, we explain how Sarduy constructs an affirming but questioning literary critique of Cuba through the practice of the 'indirect language' of Barthes
Modelo de educación de la inteligencia colectiva
The research carried out is part of the field of study of Collective Intelligence (CI) with the use of Information and Communication Technologies (ICT) in Higher Education.
The heart of this research was focused on the study, design and construction of electronic tools according to the paradigms of CI, to be applied in Higher Education. As an instrument for the implementation of these tools, an educational model with a collective work approach was designed.
The research strategy used was Design-Based Research (DBR), because it investigates a phenomenon in its real context, iterative and incremental, and it is especially recommended for the field of education. DBR in each experimental cycle updates literature, model and tools.
Empirical studies were conducted in four universities and fields of study in Latin America and Europe.
The refinements demanded by the research strategy provided the scientific and empirical evidence to design ICT tools that meet the requirements of CI. In addition, the results indicate that the educational model and the tools have generated a positive perception in teachers and students about the effects on the teaching-learning process. Based on this fact, the experimental cycles present significant contributions to the research carried out around the CI with ICT tools in Higher Education.La investigación realizada se enmarca en el campo de estudio de la Inteligencia Colectiva (IC) con el uso de las Tecnologías de la Información y la Comunicaciones (TIC) en la Educación Superior. El corazón de ésta investigación estuvo enfocada en el estudio, diseño y construcción de herramientas electrónicas acorde a los paradigmas de IC, para ser aplicadas en la Educación Superior. Como vía de instrumentación de dichas herramientas, se diseñó un modelo educativo con enfoque de trabajo colectivo. La estrategia de investigación que se utilizó fue la Investigación Basada en el Diseño (DBR), porque investiga un fenómeno en su contexto real, es iterativa e incremental, y está especialmente recomendada para el ámbito de la educación.DBR en cada ciclo experimental actualiza literatura, modelo y herramientas. Los estudios empíricos se realizaron en cuatro universidades y campos de estudio en Hispanoamérica y Europa. Los múltiples refinamientos exigidos por la estrategia de investigación, proporcionaron la evidencia científica y empírica para diseñar herramientas TIC que cumplan con los requisitos de IC. Además, los resultados indican que el modelo educativo y las herramientas han generado una percepción positiva en docentes y estudiantes sobre los efectos en el proceso de enseñanza-aprendizaje. Basados en este hecho, los ciclos experimentales presentan aportes significativos a las investigaciones que se realizan en torno a la IC con herramientas TIC en la Educación Superior
Mapping spatial variation of population aging in China's mega cities
<p>Based on the statistics of the fifth and sixth censuses in China, this paper, which focuses on the spatial distribution characteristics of aging population in China's mega cities, examines the distribution of aging in Beijing, Shanghai, Guangzhou, and Wuhan. In this paper, an Aging Degree Index and an Aging Population Mean Center have been used to analyze the spatial distribution characteristics and spatial variation trends of aging population in mega cities. According to the research, the spatial distribution of aging population shows a faster development tendency of suburbanization from two different perspectives: one tendency is centrifugal spread associated with seniors who are moving from the city center to outer suburb areas, and the other is center concentration where the seniors who lived in the outer suburb areas are moving towards the city center.</p
Effects of Chemically Modified Messenger RNA on Protein Expression
Chemically
modified nucleotides play significant roles in the effectiveness
of mRNA translation. Here, we describe the synthesis of two sets of
chemically modified mRNAs [encoding firefly Luciferase (FLuc) and
enhanced green fluorescent protein (eGFP), respectively], evaluation
of protein expression, and correlation analysis of expression level
under various conditions. The results indicate that chemical modifications
of mRNAs are able to significantly improve protein expression, which
is dependent on cell types and coding sequences. Moreover, eGFP mRNAs
with <i>N</i><sub>1</sub>-methylpseudouridine (me<sup>1</sup>ψ), 5-methoxyuridine (5moU), and pseudouridine (ψ) modifications
ranked top three in cell lines tested. Interestingly, 5moU-modified
eGFP mRNA was more stable than other eGFP mRNAs. Consequently, me<sup>1</sup>ψ, 5moU, and ψ are promising nucleotides for chemical
modification of mRNAs
Image2_Research on road surface temperature characteristics and road ice warning model of ordinary highways in winter in Hunan province, central China.png
The study of road surface temperature (Ts) characteristics in winter and the early warning method of road icing is of great significance to reduce traffic accidents and improve transportation efficiency. Using the hourly observation data of Hunan traffic meteorological stations from December 2020 to February 2022, this study analyzes the winter Ts characteristics of ordinary roads in Hunan Province, and uses the Logistic regression model to establish the temperature threshold for icing of ordinary roads in the province. So as to build a road icing early warning model hierarchically. The results show that the Ts in southern Hunan is relatively high, the Ts at most stations is above 10 °C, and the low Ts area is in western Hunan, and the stations below 8 °C are mostly distributed in this area. This may be due to the higher altitude in western Hunan. In terms of diurnal variation, the lowest value of average Ts and air temperature (Ta) in Hunan Province in winter both appeared at 7:00 Beijing Time (BT), while the highest value appeared at 15:00 BT, and the average Ta is always lower than the Ts. The temperature variation on the bridge surface is more pronounced. When the Ta is lower than −2.5 °C, more than 70% of the sites have a rapid increase in the risk of icing; and when the Ta is lower than −5°C, nearly 87% of the sites have a risk level of 4, which means icing risk is extremely high. Furthermore, combining the warning model with thermal spectrum mapping can improve the spatial resolution of the warning model and also solve the problem of lack of observations in some areas.</p
Image1_Research on road surface temperature characteristics and road ice warning model of ordinary highways in winter in Hunan province, central China.png
The study of road surface temperature (Ts) characteristics in winter and the early warning method of road icing is of great significance to reduce traffic accidents and improve transportation efficiency. Using the hourly observation data of Hunan traffic meteorological stations from December 2020 to February 2022, this study analyzes the winter Ts characteristics of ordinary roads in Hunan Province, and uses the Logistic regression model to establish the temperature threshold for icing of ordinary roads in the province. So as to build a road icing early warning model hierarchically. The results show that the Ts in southern Hunan is relatively high, the Ts at most stations is above 10 °C, and the low Ts area is in western Hunan, and the stations below 8 °C are mostly distributed in this area. This may be due to the higher altitude in western Hunan. In terms of diurnal variation, the lowest value of average Ts and air temperature (Ta) in Hunan Province in winter both appeared at 7:00 Beijing Time (BT), while the highest value appeared at 15:00 BT, and the average Ta is always lower than the Ts. The temperature variation on the bridge surface is more pronounced. When the Ta is lower than −2.5 °C, more than 70% of the sites have a rapid increase in the risk of icing; and when the Ta is lower than −5°C, nearly 87% of the sites have a risk level of 4, which means icing risk is extremely high. Furthermore, combining the warning model with thermal spectrum mapping can improve the spatial resolution of the warning model and also solve the problem of lack of observations in some areas.</p
Synthesis of Sterically Protected Xanthene Dyes with Bulky Groups at C‑3′ and C‑7′
Substitution of the xanthene scaffold
with bulky groups at C-3′
and C-7′ is expected to protect the electrophilic central methine
carbon against nucleophilic attack and inhibit stacking. However,
such structures are not readily prepared via traditional xanthene
syntheses. We have devised an alternative and convenient synthesis
to enable facile preparation of this subset of xanthene dyes under
mild conditions and in good yields
Density, Viscosity, and Refractive Index of Aqueous CO<sub>2</sub>‑Loaded and -Unloaded Ethylaminoethanol (EAE) Solutions from 293.15 to 323.15 K for Post Combustion CO<sub>2</sub> Capture
The
physical properties of densities, viscosities, and refractive
indices, which are important in kinetics and mass transfer processes
were measured for aqueous CO<sub>2</sub>-loaded and -unloaded (EAE)
solutions applied in CO<sub>2</sub> absorption in the temperature
range from 293.15 to 323.15 K at atmospheric pressure. Due to the
limitation of the instrument and corrosive behavior with increasing
concentration, the mass fractions (<i>w</i><sub>1</sub>)
of aqueous EAE solutions selected were: as 0.089, 0.178, 0.267, and
0.356, which correspond to the molar concentrations of 1, 2, 3, and
4 mol·L<sup>–1</sup>, respectively. The determined density,
viscosity and refractive index data for binary EAE+H<sub>2</sub>O
and ternary CO<sub>2</sub>+EAE+H<sub>2</sub>O systems were correlated
using Weiland et al. model, Redlich–Kister equation, extended
Arrhenius equation, and a new proposed empirical function. All the
calculated density, viscosity, and refractive index data fitted well
with experimental values at all operational conditions
Selection of appropriate reference genes for the detection of rhythmic gene expression via quantitative real-time PCR in Tibetan hulless barley
<div><p>Hulless barley (<i>Hordeum vulgare</i> L. var. <i>nudum</i>. hook. f.) has been cultivated as a major crop in the Qinghai-Tibet plateau of China for thousands of years. Compared to other cereal crops, the Tibetan hulless barley has developed stronger endogenous resistances to survive in the severe environment of its habitat. To understand the unique resistant mechanisms of this plant, detailed genetic studies need to be performed. The quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) is the most commonly used method in detecting gene expression. However, the selection of stable reference genes under limited experimental conditions was considered to be an essential step for obtaining accurate results in qRT-PCR. In this study, 10 candidate reference genes—<i>ACT</i> (Actin), <i>E2</i> (Ubiquitin conjugating enzyme 2), <i>TUBα</i> (Alpha-tubulin), <i>TUBβ6</i> (Beta-tubulin 6), <i>GAPDH</i> (Glyceraldehyde 3-phosphate dehydrogenase), <i>EF-1α</i> (Elongation factor 1-alpha), <i>SAMDC</i> (S-adenosylmethionine decarboxylase), <i>PKABA1</i> (Gene for protein kinase HvPKABA1), <i>PGK</i> (Phosphoglycerate kinase), and <i>HSP90</i> (Heat shock protein 90)—were selected from the NCBI gene database of barley. Following qRT-PCR amplifications of all candidate reference genes in Tibetan hulless barley seedlings under various stressed conditions, the stabilities of these candidates were analyzed by three individual software packages including geNorm, NormFinder, and BestKeeper. The results demonstrated that <i>TUBβ6</i>, <i>E2</i>, <i>TUBα</i>, and <i>HSP90</i> were generally the most suitable sets under all tested conditions; similarly, <i>TUBα</i> and <i>HSP90</i> showed peak stability under salt stress, <i>TUBα</i> and <i>EF-1α</i> were the most suitable reference genes under cold stress, and <i>ACT</i> and <i>E2</i> were the most stable under drought stress. Finally, a known circadian gene <i>CCA1</i> was used to verify the service ability of chosen reference genes. The results confirmed that all recommended reference genes by the three software were suitable for gene expression analysis under tested stress conditions by the qRT-PCR method.</p></div
Description of primer sequences and amplicon characteristics in ten candidate reference genes.
<p>Description of primer sequences and amplicon characteristics in ten candidate reference genes.</p
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