酪蛋白磷酸肽-无定形磷酸钙、不同玷污层的处理和储存时间对牙本质粘接的影响(英文)

研究目的:评价含有酪蛋白磷酸肽-无定形磷酸钙(CPP-ACP)的再矿化剂Tooth Mousse(TM)的使用、不同玷污层的处理以及样本储存时间对牙本质粘接微拉伸性能的影响。研究方法:将牙本质样本分成保留玷污层组和用15%乙二胺四乙酸(EDTA)处理90秒去除玷污层组。每组根据是否使用TM处理再分亚组。每个亚组分别用三种不同的粘结剂(两步法自酸蚀Clearfil SE Bond(CSE)、一步法自酸蚀G-Bond(GB)和全酸蚀Adper Single Bond 2(SB))与牙本质样本粘接,分别经过3天和6个月的去离子水储存。样本进行切割微拉伸测试并通过扫描电镜分析断裂界面模式。重要结论:经过再矿化剂TM预处理,可以减少牙齿的敏感性,并且对于这三种粘结系统经过长时间储存后的粘结性能没有影响。EDTA的处理对于长期储存的粘结性能没有显著影响。额外的TM和EDTA对短期(3天)粘接力会有效应,但对长期(6个月)的粘接力没有影响。     

Circadian rhythms in Neurospora crassa on a polydimethylsiloxane microfluidic device for real-time gas perturbations

Racetubes, a conventional system employing hollow glass tubes, are typically used for monitoring circadian rhythms from the model filamentous fungus, Neurospora crassa. However, a major technical limitation in using a conventional system is that racetubes are not amenable for real-time gas perturbations. In this work, we demonstrate a simple microfluidic device combined with real-time gas perturbations for monitoring circadian rhythms in Neurospora crassa using bioluminescence assays. The developed platform is a useful toolbox for investigating molecular responses under various gas conditions for Neurospora and can also be applied to other microorganisms.     

The effect of individualised sprint training in elite female team sport athletes: A pilot study

ABSTRACT

This study aimed to evaluate whether an individualised sprint-training program was more effective in improving sprint performance in elite team-sport players compared to a generalised sprint-training program. Seventeen elite female handball players (23 ± 3 y, 177 ± 7 cm, 73 ± 6 kg) performed two weekly sprint training sessions over eight weeks in addition to their regular handball practice. An individualised training group (ITG, n = 9) performed a targeted sprint-training program based on their horizontal force-velocity profile from the pre-training test. Within ITG, players displaying the lowest, highest and mid-level force-velocity slope values relative to body mass were assigned to a resisted, an assisted or a mixed sprint-training program (resisted sprinting in the first half and assisted sprinting in the second half of the intervention period), respectively. A control group (CG, n = 8) performed a generalised sprint-training program. Both groups improved 30-m sprint performance by ~1% (small effect) and maximal velocity sprinting by ~2% (moderate effect). Trivial or small effect magnitudes were observed for mechanical outputs related to horizontal force- or power production. All between-group differences were trivial. In conclusion, individualised sprint-training was no more effective in improving sprint performance than a generalised sprint-training program.     

Optimal Convert Strategies in Football

Abstract

A frequently occurring situation in college and professional football is that of a team catching up through two touchdowns after trailing by 14 points, with the game outcome being determined by the extra-point plays. For leagues allowing two-point converts, an optimal point-after strategy exists under quite reasonable assumptions, and depends upon the relative utility to the team of a win, tie, or loss and the probability of success with a (one-point) kick as opposed to a (two-point) run/pass. We illustrate with reference to the January 1984 Orange Bowl game, where the favored team followed a possibly suboptimal strategy, losing the game and the national championship.     

Inhalte und Strukturen prototypischer Merkmale in Fußballmannschaften

Members of a social group possess a shared social identity, which is individually represented as the group prototype. The prototype is the individual cognitive representation of all attributes, which best describes the group from the group members’ point of view. The aim of the study was to gather those attributes provided by group members of a soccer team and subsequently to describe and categorize them by means of a content analysis. Using one single open question, a total of 1581 attributes were assessed through n?=?278 soccer players (67?% male; M?=?23.5 years, SD?=?5.0 years) from 20 soccer teams. The data analysis was based on the qualitative content analysis described by Mayring (2010). Results show that the attributes mentioned by the team members can be divided into four distinct categories (social, psychological, sport specific, ecological). These categories result from intragroup synchronisations. Future research should examine which categories and subcategories seem to best represent the prototype in soccer teams.     

The early prevention of mathematics difficulty: its power and limitations

In this article, the authors consider the power and limitations of responsiveness-to-intervention (RTI) for reducing the need for ongoing and intensive services for the segment of the school population traditionally identified as having a learning disability in mathematics. To assess the robustness of RTI, the authors describe four studies with strong demonstrations of efficacy, as they considered the percentage of students who failed to respond, the post-tutoring achievement gap between tutored and not-at-risk students, and the extent of transfer across components of the mathematics curriculum. The authors then discuss implications and additional research questions pertaining to mathematics intervention generally and within the context of RTI. They conclude with a proposal for an expanded conceptualization of RTI.     

On the potential for using immersive virtual environments to support laboratory experiment contextualisation

This paper explores the hypothesis that embedding a laboratory activity into a virtual environment can provide a richer experimental context and hence improve the understanding of the relationship between a theoretical model and the real world, particularly in terms of the model's strengths and weaknesses. While an identified learning objective of laboratories is to support the understanding of the relationship between models and reality, the paper illustrates that this understanding is hindered by inherently limited experiments and that there is scope for improvement. Despite the contextualisation of learning activities having been shown to support learning objectives in many fields, there is traditionally little contextual information presented during laboratory experimentation. The paper argues that the enhancing laboratory activity with contextual information affords an opportunity to improve students’ understanding of the relationship between the theoretical model and the experiment (which is effectively a proxy for the complex real world), thereby improving their understanding of the relationship between the model and reality. The authors propose that these improvements can be achieved by setting remote laboratories within context-rich virtual worlds.     

Children's expected interpersonal consequences of communicating their affective state and reported likelihood of expression

This study explored several factors associated with expected outcome of emotional expression and likelihood of expression among children. These variables were posited to be a reflection of children's affective display rules. Differences in outcome expectancies and likelihood of expression were assessed as a function of sex of parent, sex of subject, grade, and type of affect. 125 first-, fourth-, and sixth-grade children (mean ages, 6-9, 9-2, and 11-7, respectively) were randomly assigned to 1 of 2 experimental conditions involving either sad or angry affect inductions. Older boys reported less positive expectancies and lower likelihood of expression than younger boys; and boys had less positive expectancies and lower likelihood of expression for sadness than girls. A high correlation was obtained between outcome expectancy and likelihood of expression; the correlation was higher for sadness than anger, and higher among males than females. These results suggest that socialization practices tend to be directed toward the suppression of sadness among males.     

Political Journalists’ Interaction Networks

This article examines with whom political journalists interact on Twitter and what information they share. These relations are explored by combining a content analysis and a network analysis of interaction patterns. The activities published on journalists’ personal accounts are studied. Prior research has shown that elite journalists, in particular, mainly seek to remain gatekeepers and tend to normalize emerging communication spaces. Only one-quarter of the parliamentary correspondents in the German Federal Press Conference had an individual Twitter profile as of February 2014. The content analysis of all tweets published during a week in March 2014 (N?=?2210) reveals that German political journalists clearly normalize Twitter to fit existing practices: the journalists mostly tweeted about publicly relevant communication and reported in an information-oriented style. Transparency was limited on their topics of interest, and they did not provide direct opportunities for the audience to become more active in the news-creation process. The network analysis shows that the correspondents especially incorporated politicians into their regular circle of contacts. Nevertheless, the interaction networks were clearly dominated by exchanges between journalists. In this way, journalists’ tweets allow us to observe expert talks rather than encouraging users to participate in a discussion.     

From plans to actions: A process model for why feedback features influence feedback implementation

Implementing peer feedback in revisions is a complex process involving first planning to fix problems and then actual implementing feedback through revisions. Both phases are influenced by features of the peer feedback itself, but potentially in different ways, and yet prior research has not examined their separate role in planning or the mediating role of planning in the relationship of feedback features and implementation. We build on a process model to investigate whether feedback features had differing relationships to plans to ignore or act on feedback versus actual implementation of feedback in the revision, and whether planning mediated the relationship of feedback features and actual implementation. Source data consisted of peer feedback comments received, revision plans made, and revisions implemented by 125 US high school students given a shared writing assignment. Comments were coded for feedback features and implementation in the revision. Multiple regression analyses revealed that having a comment containing a specific solution or a general suggestion predicted revision plans whereas having a comment containing an explanation predicted actual implementation. Planning mediated the relationship to actual implementation for the two feedback features predicting plans, suggestion and solution. Implications for practice are discussed.