Self-concept and attitudes as factors in the achievement of preservice teachers     

Richard L. Campbell  Luis Martinez-Perez 《科学教学研究杂志》1977,14(5):455-459

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Evaluation of a new equation for estimating low-density lipoprotein cholesterol through the comparison with various recommended methods     

Eduardo Martínez-Morillo  María García-García  María Angeles Luengo Concha  Luis Rello Varas 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(1)

IntroductionThe accurate estimation of low-density lipoprotein cholesterol (LDL) is crucial for management of patients at risk of cardiovascular events due to dyslipidemia. The LDL is typically calculated using the Friedewald equation and/or direct homogeneous assays. However, both methods have their own limitations, so other equations have been proposed, including a new equation developed by Sampson. The aim of this study was to evaluate Sampson equation by comparing with the Friedewald and Martin-Hopkins equations, and with a direct LDL method.Materials and methodsResults of standard lipid profile (total cholesterol (CHOL), high-density lipoprotein cholesterol (HDL) and triglycerides (TG)) were obtained from two anonymized data sets collected at two laboratories, using assays from different manufacturers (Beckman Coulter and Roche Diagnostics). The second data set also included LDL results from a direct assay (Roche Diagnostics). Passing-Bablok and Bland-Altman analysis for method comparison was performed.ResultsA total of 64,345 and 37,783 results for CHOL, HDL and TG were used, including 3116 results from the direct LDL assay. The Sampson and Friedewald equations provided similar LDL results (difference ≤ 0.06 mmol/L, on average) at TG ≤ 2.0 mmol/L. At TG between 2.0 and 4.5 mmol/L, the Sampson-calculated LDL showed a constant bias (- 0.18 mmol/L) when compared with the Martin-Hopkins equation. Similarly, at TG between 4.5 and 9.0 mmol/L, the Sampson equation showed a negative bias when compared with the direct assay, which was proportional (- 16%) to the LDL concentration.ConclusionsThe Sampson equation may represent a cost-efficient alternative for calculating LDL in clinical laboratories.  相似文献   

Ecological dynamics of continuous and categorical decision-making: The regatta start in sailing     

Duarte Araújo  Keith Davids  Ana Diniz  Luis Rocha  João Coelho Santos  Gonçalo Dias 《European Journal of Sport Science》2015,15(3):195-202

Abstract

Ecological dynamics of decision-making in the sport of sailing exemplifies emergent, conditionally coupled, co-adaptive behaviours. In this study, observation of the coupling dynamics of paired boats during competitive sailing showed that decision-making can be modelled as a self-sustained, co-adapting system of informationally coupled oscillators (boats). Bytracing the spatial–temporal displacements of the boats, time series analyses (autocorrelations, periodograms and running correlations) revealed that trajectories of match racing boats are coupled more than 88% of the time during a pre-start race, via continuous, competing co-adaptions between boats. Results showed that both the continuously selected trajectories of the sailors (12 years of age) and their categorical starting point locations were examples of emergent decisions. In this dynamical conception of decision-making behaviours, strategic positioning (categorical) and continuous displacement of a boat over the course in match-race sailing emerged as a function of interacting task, personal and environmental constraints. Results suggest how key interacting constraints could be manipulated in practice to enhance sailors' perceptual attunement to them in competition.  相似文献   

Measuring the impact of inquiry-based learning on outcomes and student satisfaction     

José Luis Zafra-Gómez  Isabel Román-Martínez  María Elena Gómez-Miranda 《Assessment & Evaluation in Higher Education》2015,40(8):1050-1069

The aim of this study is to determine the impact of inquiry-based learning (IBL) on students’ academic performance and to assess their satisfaction with the process. Linear and logistic regression analyses show that examination grades are positively related to attendance at classes and tutorials; moreover, there is a positive significant relationship between academic performance and IBL, which is considered useful for better understanding of the subject. While students’ satisfaction is directly associated with class attendance and motivation and with the perceived usefulness of IBL, it is unaffected by attendance at tutorials. We conclude, therefore, that students become more involved in learning and acquire increased knowledge of the subject when an IBL-based method is followed.  相似文献   

Dissipative output feedback control for semi-Markovian jump systems under hybrid cyber-attacks     

Huiyan Zhang  Xiuli He  Luis I. Minchala  Peng Shi 《Journal of The Franklin Institute》2021,358(5):2683-2702

In this paper, the dissipativity-based dynamic output feedback controller (DOFC) design for Semi-Markovian jump systems under stochastic cyber-attacks is first proposed. It is assumed that the time-varying uncertainties obey Bernoulli-distribution and transition probability matrix is time-varying and partially accessed. By utilizing the dissipativity-based technique, sufficient conditions for the existence of the DOFC are obtained to ensure the exponential stability with a strict dissipative performance of the resulted system. Next, the proposed results are improved by fractionalizing the time-varying transition probability matrix and the corresponding DOFC gains are obtained by cone complementarity linearization algorithm. Simulations results are provided to demonstrate the effectiveness and theoretical value of the proposed dissipativity-based DOFC design method.  相似文献   

Applying the technology acceptance model to a Spanish City Hall     

José Luis Moreno Cegarra  Juan Gabriel Cegarra Navarro  José Rodrigo Córdoba Pachón 《International Journal of Information Management》2014

This paper examines the relative importance and significance of the four technology enablers introduced by Davis (1989) in the technology acceptance model (TAM) (perceived ease of use, perceived usefulness, attitude towards using and behavioural intention) for use on four different levels of citizen engagement in e-government (null, publish, interact and transact). An extended technology acceptance model (TAM) is developed to test citizen engagement towards online e-government services from a sample of 307 citizens who used the benefits advisor tool within a Spanish City Hall. Although the proposed model follows TAM and explains the intention towards the actual use of e-government by postulating four direct determinants, “A, PU, PEOU and BI” have been considered as parallel processes, meaning that each can have separate influence in different levels of citizen engagement. To achieve this goal, a multinomial logistic regression is developed and tested to confirm the explanatory power of the four technology enablers on the four different levels of e-government. Our findings further suggest that in order to implement e-government, some of the enablers matter more than others to move from one level of citizen engagement to another. The main contribution of the paper is to question the use of existing models which seek to represent the relationship between technology enablers and the adoption of e-government services without considering their impacts on citizens’ engagement. The implications of the findings are discussed and useful insights are provided in relation to policy recommendations geared to create appropriate conditions to build citizens’ engagement intent of use of e-government services.  相似文献   

Development of a three-dimensional cell culture system based on microfluidics for nuclear magnetic resonance and optical monitoring     

Vicent Esteve  Javier Berganzo  Rosa Monge  M. Carmen Martínez-Bisbal  Rosa Villa  Bernardo Celda  Luis Fernandez 《Biomicrofluidics》2014,8(6)

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Life Securitisation,the Event Object of Insurance and the Strategisation of Time     

Luis Lobo-Guerrero 《Journal of Cultural Economy》2014,7(3):353-370

Understanding the matter of insurability as a problem of governing uncertainty has led to thinking ‘the event’ as the object of insurance. How the event is understood and conceptualized determines to a great extent the ways in which its related uncertainty will be rendered. This, in turn, will determine how such uncertainty will be managed. Although this idea has been widely explored with important nuances by various scholars, what has not been discussed in great detail is the problematic idea of temporality and the role time plays in helping constitute the event object of insurance. Such a problem is of great relevance for pushing forward the debate on the limits of insurability. The empirical cases used in this article, Swiss Re's Vita and Kortis, launched and developed during the last decade, relate to hedging the exposure of life and health insurance portfolios to events that would generate excess mortality and excess vitality. The schemes, as explored here, are not simply actuarial, although actuarial practice still figures prominently in their crafting. They involve the strategic articulation of varied forms of knowledge that enshrine particular understandings of time and produce the truth-base of insurable events.  相似文献   

Alienation in mathematics education: a problem considered from neo-Vygotskian approaches     

Luis Radford  Wolff-Michael Roth 《Educational Studies in Mathematics》2017,96(3):367-380

In a recent article published in this journal, Williams (Educational Studies in Mathematics, 92, 59–72, 2016) offers a critique of neo-Vygotskian perspectives exemplified in recent work on the funds of knowledge and on cultural-historical activity theoretic perspectives. The critique has great value in that it asks interesting questions that often go unnoticed and fail to be discussed in mathematics education research—e.g., the question of alienation or the role of agency in Vygotsky’s notion of the zone of proximal development. Despite the great value of the questions raised, the critique fails because its idealist theoretical epistemological underpinning is at odds with Vygotsky’s thought and cultural-historical activity research in general. The critique falls short especially on the point of realizing the materialist dialectical method Vygotsky employed. The goal of this article is to address Williams’ critique by (a) revisiting the main argument of the critique, (b) articulating the departures of the critique from the materialist dialectical method, (c) conceptualizing development along the theoretical lines of the late (Spinozist-Marxian) Vygotsky, and (d) formulating a materialist dialectical approach to alienation. We conclude by summarizing three main problems of the critique.  相似文献   

Reasons and mediators in the development and communication of personal digital stories     

Rodríguez-Illera  José Luis  Barberà Gregori  Elena  Molas-Castells  Núria 《Education and Information Technologies》2021,26(4):4093-4109

The expansion of access to devices, as well as the production and publication options in social networks requires a broader definition of the traditional notion of personal digital storytelling. To get a deeper understanding of these practices in the group of adolescents, the objective of this article is to analyze what are the reasons that direct the publications of personal stories and what kind of filters, agents and consequences are articulated in these stories. To do this, the most qualitative part of an investigation on teenagers’ internet publication guidelines is synthesized. Specifically, the results of a semi-structured interview with 12 adolescents between 12 and 20 years are shown. The answers show that the interviewees’ perspective on what a digital story is goes beyond the format and varies depending on the network where it is published and the type of content. Thus, the emphasis and motivation of the publication has shifted from the digital - which has been incorporated with something normal and not differential - towards the personal, focusing the publications on the daily life of young people. An extension and refinement of the public-private dichotomy has been identified, maintaining general privacy guidelines above the dissemination of publications. As for filters, publications are preceded by the widespread use of image modification tools. Finally, the answers show the influence of personal agents, mostly friends and brothers, and technology agents, which determine the relationship between the type of story and the network where it is published.

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