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In this work, the characteristics of a simulator for channel coding techniques used in communication systems, are described. This software has been designed for engineering students in order to facilitate the understanding of how the error correcting codes work. To help students understand easily the concepts related to these kinds of codes, a user-friendly interface has been developed using the MATLAB environment, since it provides many toolboxes related to communication systems.  相似文献   
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Abstract

This paper sought to shed light on the beliefs, aspirations and values in relation to education that shape parental ways of involvement among Chilean urban lower-middle-class parents. Using the capability approach as the main theoretical framework and a critical epistemology, the discussion focuses on the way in which the pre-eminence of instrumental and positional dimensions of education arguably places limitations on how education is understood and valued; sets boundaries for parental involvement and overloads families. This situation ultimately diminishes the power of education to disrupt intergenerational cycles of disadvantage among Chilean urban lower-middle-class families.  相似文献   
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IntroductionSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests have been suggested as an additional diagnostic tool in highly suspected cases with a negative molecular test and determination of seroprevalence in population. We compared the diagnostic performance of eight commercial serological assays for IgA, IgM, and IgG antibodies to the SARS-CoV-2 virus.Materials and methodsThe comparison study was performed on a total of 76 serum samples: 30 SARS-CoV-2 polymerase chain reaction (PCR)-negative and 46 SARS-CoV-2 PCR-positive patients with asymptomatic to severe disease and symptoms duration from 3-30 days. The study included: three rapid lateral flow immunochromatographic assays (LFIC), two enzyme-linked immunosorbent assays (ELISA), and three chemiluminescence immunoassays (CLIA).ResultsAgreement between IgM assays were minimal to moderate (kappa 0.26 to 0.63) and for IgG moderate to excellent (kappa 0.72 to 0.92). Sensitivities improved with > 10 days of symptoms and were: 30% to 89% for IgM; 89% to 100% for IgG; 96% for IgA; 100% for IgA/IgM combination; 96% for total antibodies. Overall specificities were: 90% to 100% for IgM; 85% to 100% for IgG; 90% for IgA; 70% for IgA/IgM combination; 100% for total antibodies. Diagnostic accuracy for IgG ELISA and CIA assays were excellent (AUC ≥ 0.90), without significant difference. IgA showed significantly better diagnostic accuracy than IgM (P < 0.001).ConclusionThere is high variability between IgM assays independently of the assay format, while IgG assays showed moderate to perfect agreement. The appropriate time for testing is crucial for the proper immunity investigation.  相似文献   
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This article presents part of the research performed in a project from 2008 to 2013, regarding the introduction of the Reggio Emilia approach to Slovene preschool educators. The study’s aim was to recognize the possible influence of the training—from 2009 to 2011—in this project on educators’ viewpoints and the promotion of children’s participation in practice. We believe that a potential reform of the Slovene national curriculum should establish the participation of children as one of its key principles. It seems that the two-year intensive training of educators, followed by projects in preschool practice, has been a successful step in this direction.  相似文献   
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This intervention study aimed at helping undergraduate students of psychology learn to use the discursive resources useful to make academic voice visible in their texts and to improve their writing practices. The intervention involved tutorial meetings and collaborative revisions in two different learning environments, on-line and face-to face. The final text quality, the students’ knowledge and the amount and the quality of revisions were assessed in both conditions. Results show that the quality of the texts improved for both intervention groups in contrast with for control group, and better texts were related with higher rates of revision and more students’ satisfaction with the intervention.  相似文献   
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Whole body vibration (WBV) is used as a training method but its physical risk is not yet clear. Hence, the aim of this study is to assess the exposure to WBV by a measure of acceleration at the lower limb under dynamic and static postural conditions. The hypothesis of this paper is that this assessment is influenced by the frequency, position, and movement of the body. Fifteen healthy males are exposed to vertical sinusoidal vibration at different frequencies (20–60 Hz), while adopting three different static postures (knee extension angle: 180°, 120° and 90°) or performing a dynamic half-squat exercise. Accelerations at input source and at three joints of the lower limb (ankle, knee, and hip) are measured using skin-mounted accelerometers. Acceleration values (g) in static conditions show a decrease in the vibrational dose when it is measured at a more proximal location in the lower extremity. The results of the performed statistical test show statistically significant differences (p < 0.05) in the transmissibility values caused by the frequency, the position, and to the presence of the movement and its direction at the different conditions. The results confirm the initial hypothesis and justify the importance of a vibration assessment in dynamic conditions.  相似文献   
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