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81.
Heart failure (HF) is a frequent chronic disease in elderly people and represents a major health and economic burden. The accurate diagnosis of HF and the identification of high risk patients is mandatory to select the appropriate therapy and care. HF is associated to cardiac remodeling and inflammation and to the release of neurohormones. If natriuretic peptides remain the biomarkers of choice for the diagnosis and the prognosis of HF, several biomarkers related to cardiac remodeling and inflammation are available for testing and may add valuable information for the risk estimation of HF patients and for the selection of the most appropriated therapy. Furthermore, the quest for new efficient biomarkers of cardiac remodeling and inflammation is still ongoing and new candidates have been identified for a potential use in daily clinical practices. However, before their potential translation to routine parameters several challenges ranging form the analytical validation to the cost-effectiveness estimation should be considered.  相似文献   
82.
To prepare a biosynthetic module in an infochemical communication project, we designed a silicon/glass microreactor with anti-adsorption polyelectrolyte multilayer coating and immobilized alcohol acetyl transferase (atf), one of the key biosynthetic enzymes of the pheromone of Spodoptera littoralis, on agarose beads inside. The system reproduces the last step of the biosynthesis in which the precursor diene alcohol (Z,E)-9,11-tetradecadienol is transformed into the major component (Z,E)-9,11-tetradecadienyl acetate. The scope of this study was to analyze and implement a multilayer, anti-adsorption coating based on layer-by-layer deposition of polyethylenimine/dextransulfate sodium salt (PEI/DSS). The multilayers were composed of two PEI with molecular weights 750 and 1.2 kDa at pH 9.2 or 6.0. Growth, morphology, and stability of the layers were analyzed by ellipsometry and atomic force microscopy (AFM). The anti-adsorption functionality of the multilayer inside the microreactor was validated. The activity of His(6)-(atf) was measured by gas chromatography coupled to mass spectrometer (GC-MS).  相似文献   
83.
Combining home–school literacy bags with preschool family literature circles provided a strong foundation for family involvement at home and school during this year-long Reading Partners project, and helped parents become essential partners in their children’s literacy development. Using home–school literacy bags, children and parents learned how to combine expressive arts and emergent literacy strategies including alphabet recognition, phonemic and phonological awareness, and oral language fluency. State-of-the-art activities designed for each of the multiple intelligences met the needs of diverse students with many different learning styles and interests. As families participated in fall and spring school-based Festivals in which they shared the literacy bags in small group family literature circles, they demonstrated children’s emerging literacy skills in a relaxed, yet highly engaging atmosphere.  相似文献   
84.
The transition from teacher training into the teaching profession is seen to be key in the biography of a teacher. Yet there is a lack of enquiry into the development of the content knowledge (CK) and pedagogical content knowledge (PCK) held by teachers at the end of their education, and into the significance of this knowledge for situational and behavioural cognition. On the basis of data from the international comparative study TEDS-M 2008 and the Germany-based 2012 follow-up, this contribution investigates the knowledge and skills development of teachers during the transition from teacher training to the teaching profession in a four-year longitudinal study with n = 171 mathematics teachers. Three test formats (paper-and-pencil, video-vignettes and speed tests) are used to examine various indicators for teacher expertise. In addition to the analysis of changes in mathematical CK and PCK levels, path analysis is used to determine the extent to which this knowledge functions as a predictor for the perception and interpretation of classroom situations, the decision-making in these situations, and the quick identification of student mistakes. The results show only small changes in the group mean (for MCK there is a small loss, whereas MPCK remains constant), but high fluctuation (i. e. weak correlation) in the MPCK ranking between the two measurement occasions, pointing to differential learning effects gained from teaching practice. There are also significant differences in predictability: MCK is important for the speed indicators of teacher expertise; MCK and MPCK for the perception and interpretation of situations, and for the generation of action strategies. These findings can on the one hand help to facilitate the evaluation of beginning teachers’ need for support and, on the other hand, they indicate the necessity for the early integration of practice-based elements into teacher training programmes with the aim of developing PCK and related skills.  相似文献   
85.
Discrimination reversal learning has been used as a measure of species flexibility in dealing with changes in reinforcement contingency. In the simultaneous-discrimination, midsession-reversal task, one stimulus (S1) is correct for the first half of the session, and the other stimulus (S2) is correct for the second half. After training, pigeons show a curious pattern of choices: They begin to respond to S2 well before the reversal point (i.e., they make anticipatory errors), and they continue to respond to S1 well after the reversal (i.e., they make perseverative errors). That is, pigeons appear to be using the passage of time or the number of trials into the session as a cue to reverse, and are less sensitive to the feedback at the point of reversal. To determine whether the nature of the discrimination or a failure of memory for the stimulus chosen on the preceding trial contributed to the pigeons’ less-than-optimal performance, we manipulated the nature of the discrimination (spatial or visual) and the duration of the intertrial interval (5.0 or 1.5 s), in order to determine the conditions under which pigeons would show efficient reversal learning. The major finding was that only when the discrimination was spatial and the intertrial interval was short did the pigeons perform optimally.  相似文献   
86.
The recent convergence of digital cameras into mobile phones with Internet connectivity has provided the opportunity for individuals and organisations to adopt new image-making practices. The widespread use of photo-sharing and social networking platforms for sharing, accessing and storing digital photographs is presenting scholars in the social sciences with new areas of research that address the nature of digital photography. By examining the technological, social and cultural factors involved in contemporary image-making practices, scholars are presenting new concepts regarding the characteristics of digital photographs that impact archival activities aimed at managing and preserving trustworthy digital records. This article identifies and discusses the key concepts emerging from social science research on digital photography that are most relevant to the archival field. Analysis of the findings of these studies suggests that new technologies and social practices are changing how people use digital photographs and their expectations of permanence. Therefore, archivists need to be engaged in interdisciplinary discussions regarding the evolution of photographic practices and emerging characteristics of digital photographs in order to anticipate the management and preservation activities required to protect contemporary visual records for future use.  相似文献   
87.
This article reports on a study of the awareness, perceptions and use of e-books by academic staff in Further Education (FE) colleges throughout Northern Ireland (NI). It is the first comprehensive study of e-book use by FE faculty in NI and fills a significant gap in the research literature on e-books in education, which has tended to focus on Higher Education and the university setting. Data was collected through an online survey which was distributed to FE faculty across NI. The findings show that although FE academic staff are receptive to e-books and welcome them as a resource, poor reading experience and lack of awareness of relevant titles have had an impact. In particular, the research found that 40% of academic staff, in post less than five years, had not used e-books. Greater availability of titles, promotion, and better integration within teaching and learning emerge as key requisites for effective service delivery and enhancement of e-books within FE, as does the need for better targeted instruction and training aimed at academic staff. Understanding patrons' views, awareness, needs, habits and expectations in relation to e-books is crucial to help direct collection content while budgets remain tight and physical space limited.  相似文献   
88.
The TEMPUS/PHARE Multilateral Programme was initiated in 1990 by the European Communities with a view to improving training by means of the structural reform of the higher education systems in the central and eastern European countries. The results are now widely visible. The question to be asked is whether or not these results are limited solely to the educational field or whether the improvement of training has not also had an impact on society and the economy. In the particular case of the central and eastern European countries that are currently moving from one social system to another, the task is one of finding out in what respects and to what extent the changes in the higher education systems have contributed to this transition.  相似文献   
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