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81.
En el campo del lenguaje y la lectoescritura, la renovación educativa parece estar situándose en la batalla por el diseño abierto y la evaluación informal. En este artículo se propone un modelo teórico para la lectoescritura flexible que pueda soportar las posibilidades que se abren y evitar los inconvenientes que amenazan a los actuales métodos informales de renovación a los que está dedicado el tema central de este número.  相似文献   
82.
This paper presents conditions to assure the exponential stability in probability for autonomous switching linear systems. The switching signal acting on the autonomous system produces intervals that follow independent, identically distributed stochastic processes—the stability then follows by verifying simple-to-check linear matrix inequalities.  相似文献   
83.
In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications.  相似文献   
84.
Research in Science Education - The theory of evolution is the backbone of the biological sciences. Arguably, this is the reason why evolution education is an extensively investigated issue in...  相似文献   
85.

Covid-19 literacy, induced by the coronavirus disease (2019), is characterized as the understanding of Covid-19 as well as informed decisions based upon this understanding. This type of literacy is closely related to health literacy, scientific literacy, and scientific media literacy. It may be obvious to say that Covid-19 literacy is a key factor for governments to effectively manage the Covid-19 transition. However, lack of literature exists about Covid-19 literacy among university students. Therefore, the current study aimed to determine the Covid-19 literacy level among 4168 students from a Colombian university. The data were derived from students’ responses to a 25–item anonymous online self-reporting questionnaire. We found that 21–25-year age group, graduate students,?students enrolled prior to 2015, and medical students had a significantly higher mean score. Moreover, the Internet (86.8%) was the most popular source of information from which participants gained most information regarding Covid-19. Furthermore, 58.5% of the participants considered health workers as a source that can provide accurate information. Most importantly, the findings reveal the students’ knowledge about (1) the role of an eventual process of vaccination, (2) the test currently used as diagnostic for Covid-19, and (3) the fatality rate, three aspects of Covid-19 literacy that deserve more attention. The findings provide a useful basis for the formulation of policies and concrete actions in improving Covid-19 literacy.

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86.
A Chebyshev collocation method, an expansion method, has been proposed in order to solve the systems of higher-order linear integro-differential equations. This method transforms the IDE system and the given conditions into the matrix equations via Chebyshev collocation points. By merging these results, a new system which corresponds to a system of linear algebraic equations is obtained. The solution of this system yields the Chebyshev coefficients of the solution function. Some numerical results are also given to illustrate the efficiency of the method. Moreover, this method is valid for the systems of differential and integral equations.  相似文献   
87.
In the following essay, I will discuss D.Johnson's argument in her ETHICOMP99 KeynoteSpeech (Johnson 1999) regarding the possiblefuture disappearance of computer ethics as anautonomous discipline, and I will analyze somelikely objections to Johnson's view.In the future, there are two ways in whichcomputer ethics might disappear: (1) therejection of computer ethics as an aspect ofapplied ethics, or (2) the rejection ofcomputer ethics as an autonomous discipline.The first path, it seems to me, would lead tothe death of the entire field of appliedethics, while the second path would lead onlyto the death of computer ethics as a separatesubject. Computer technology is becoming very pervasive,and each scientific field includes somediscipline-specific computing. For the likelyforeseeable future, disciplines such asbioethics and engineering ethics will have todeal with ethical issues involving the role ofcomputers. I will argue that computer ethics inthis sense is unlikely to disappear, even ifcomputer ethics ceases to be considered as aseparate discipline.In order to understand which path will befollowed by computer ethics, I will compareJohnson's argument with ideas of earlierthinkers like N. Wiener (1950) and B. Russell(1932). Although Russell did not specificallyconsider computer technology, he had somegood intuitions about the development ofsocieties by means of technology.My conclusion will be two-fold: (1) thatapplied ethics will not die, but it may make nosense in the future to talk about computerethics as a separate field; and (2) thatcomputer ethics will not simply become``ordinary ethics', contrary to Johnson's view.  相似文献   
88.
The aim of this article is to present the Procedure for the Assessment of Thinking in Interaction (PAT), an instrument for the assessment of shared thinking. Following an introduction of our concept or “shared thinking”, such as appears in contexts of interaction, we present the results and conclusions obtained from its use in a cross-sectional and a longitudinal developmental study.  相似文献   
89.
The current state of the planet’s environmental deterioration calls for formal educational contexts to implement effective environmental proposals which nurture action competence. The aim of this paper is to examine the educational proposals in formal contexts that have been published in the two research journals of greatest impact on Environmental Education during the period 2008–2013, and to analyse how they contribute to the development of action competence. Special attention is paid to research (i) based on real participation by students; (ii) promotes reflection on the complexity of environmental issues; (iii) facilitates critical thinking; (iv) encourages autonomous and responsible decision-making and (v) involves communities. Our results show that these approaches can help improve the development of action-focused environmental education and bring to light a series of challenges for future research.  相似文献   
90.
A retrospective investigation of 97 psychologically maltreated children showed a clear relationship between clinical symptoms and the intensity of the abuse. Parental neglect resulted in impairment of intellectual and locomotor development and emotional and behavioral disorders. Neurotic manifestations of regressive type appeared in nearly half the preadolescents who suffered severe psychological abuse. Children under 6 years of age presented functional symptoms, including regression in toilet training and sleep disorders secondary to inadequate mothering.  相似文献   
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