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121.
This paper focuses particularly on the role of municipal science consultants in developing and maintaining network activities and connections among primary school science teachers. The hypothesis is that consultants play a crucial role in supporting strategic planning, and sustaining contacts and activities within professional learning networks. The research is framed by a project that involved 80 primary science teachers in 20 schools. The aim of the project was to develop network activities that facilitate sustainable change of the participating schools’ collective culture and practice of science teaching. The authors were involved as researchers and evaluators in the project. Data consist of reports from the consultants about their participation in various network activities, school assessment reports and a longitudinal survey. Three distinct cases are analysed through the use of a framework of professional learning networks to assess the consultants’ opportunities and constraints in terms of participating in network development. The results indicate that the consultants’ roles in successful network formation is characterized by personal stable contacts within the science teacher community in the municipality, availability of municipal resources to support network activities, participation in strategic planning of municipal network support, and facilitation of the development of new teaching activities within schools or in collaboration between schools. These four distinctive features of municipal science consultants’ participation in supporting network activities enable the participants to share and develop teaching activities.  相似文献   
122.
Since 2005, Outstanding Universal Value (OUV) is the standard by which United Nations Educational Scientific and Cultural Organization (UNESCO) evaluates world cultural heritage site suitability. The sites worthy of UNESCO preservation as well as the parameters used to demonstrate OUV are diverse. Our study focused on the uniquely distinguished rural landscape sites and the OUV parameter of integrity. Integrity however, is an elusive concept for which UNESCO provides no definitional protocol, and for which the scientific community objects to a static or pure historical interpretation. Given this, our work aims to analyse the concept of integrity and how it can be used to preserve the heritage of rural landscapes. After reviewing the UNESCO approach, we focused on the international scientific debate on the meaning and application of integrity. We designed and conducted a comparative study of UNESCO rural landscapes selected from the 2011 World Heritage List. Documents describing the historical, rural, and agro-ecological features of each of the fourteen rural sites were analysed. From this, several historical and ecological parameters were chosen as “values to have” and several socio-economic and management parameters were chosen as “values to maintain” to assess the integrity of each landscape. Our results found integrity to be a value of both cultural and natural landscapes and that it is key to site identity. We demonstrated that UNESCO assigns a high value to the following parameters: historical features, traditional crops and local products, land-use and agricultural practice permanence, and the presence of architecture related to agricultural activity. Finally, we found the relationship between culture and nature to characterize best the integrity of a rural landscape, rather than nature or culture alone.  相似文献   
123.

Background:

In vitro hemolysis can be induced by several biological and technical sources, and may be worsened by forced aspiration of blood in vacuum tubes. This study was aimed to compare the probability of hemolysis by drawing blood with a commercial evacuated blood collection tube, and S-Monovette used either in the “vacuum” or “aspiration” mode.

Materials and methods:

The study population consisted in 20 healthy volunteers. A sample was drawn into 4.0 mL BD Vacutainer serum tube from a vein of one upper arm. Two other samples were drawn with a second venipuncture from a vein of the opposite arm, into 4.0 mL S-Monovette serum tubes, by both vacuum an aspiration modes. After separation, serum potassium, lactate dehydrogenase (LD) and hemolysis index (HI) were tested on Beckman Coulter DxC.

Results:

In no case the HI exceed the limit of significant hemolysis. As compared with BD Vacutainer, no significant differences were observed for potassium and LD using S-Monovette with vacuum method. Significant increased values of both parameters were however found in serum collected into BD Vacutainer and S-Monovette by vacuum mode, compared to serum drawn by S-Monovette in aspiration mode. The mean potassium bias was 2.2% versus BD Vacutainer and 2.4% versus S-Monovette in vacuum mode, that of LD was 2.7% versus BD Vacutainer and 2.1% versus S-Monovette in vacuum mode. None of these variations exceeded the allowable total error.

Conclusions:

Although no significant macro-hemolysis was observed with any collection system, the less chance of producing micro-hemolysis by S-Monovette in aspiration mode suggest that this device may be used when a difficult venipuncture combined with the vacuum may increase the probability of spurious hemolysis.  相似文献   
124.
Abstract

We investigated the mechanical properties of the triceps surae between professional, junior, and non-football players. Fifty-nine men participated in this study. The mechanical properties of the right legs’ triceps surae were measured in vivo using a free oscillation technique; no significant differences existed between the groups. The mean results for musculo-articular stiffness, damping coefficient, and damping ratio were as follows: professional football players (21523 N· m?1, 330.8 N · s · m?1, and 0.201); junior football players (21063 N · m?1, 274.4 N · s · m?1, and 0.173); and non-players (19457 N · m?1, 281.5 N · s · m?1, and 0.184). When analysed according to position, the results were as follows: defender (21447 N · m?1, 308.6 N · s · m?1, and 0.189); midfielder (20762 N · m?1, 250.7 N · s · m?1, and 0.157); winger (21322 N · m?1, 335.1 N · s · m?1, and 0.212); forward (22085 N · m?1, 416.2 N · s · m?1, and 0.254); and non-players (19457 N · m?1, 281.5 N · s · m?1, and 0.184).

Thus, football training, football games, and the position played had no effect on triceps surae mechanical properties. These results may be attributed to opposing adaptations between different types of training that are usually implemented in football. Alternatively, the minimum strain amplitude and/or frequency threshold of the triceps surae required to trigger adaptations of mechanical properties might not be achieved by football players with football training and matches.  相似文献   
125.
126.
Many studies have shown that learning to read in a second language (L2) is similar, in many ways, to learning to read in a first language (L1). Nevertheless, reading development also relies upon oral language proficiency and is greatly influenced by orthographic consistency. This longitudinal study aimed to analyze the role of linguistic predictors (phonological awareness, letter knowledge, pseudoword repetition, morphosyntactic comprehension, lexical knowledge and rapid naming) in reading outcomes (fluency, accuracy and comprehension) in a group of bilingual children (n = 30) reading Italian as an L2, compared to a group of monolingual children (n = 56). We ran a multi-group structural equation model. Our findings showed that rapid automatized naming was a significant predictor of reading speed in both groups. However, the study revealed different patterns of predictors for reading accuracy, predictors for monolinguals being LK, phonological awareness and lexical knowledge, while pseudoword repetition was a predictor for bilinguals. Morphosyntactic comprehension was the most significant predictor of comprehension skills in bilingual children. Implications for clinical and educational settings are discussed.  相似文献   
127.
There is currently a growing interest in control of stretching of DNA inside nanoconfined regions due to the possibility to analyze and manipulate single biomolecules for applications such as DNA mapping and barcoding, which are based on stretching the DNA in a linear fashion. In the present work, we couple Finite Element Methods and Monte Carlo simulations in order to study the conformation of DNA molecules confined in nanofluidic channels with neutral and charged walls. We find that the electrostatic forces become more and more important when lowering the ionic strength of the solution. The influence of the nanochannel cross section geometry is also studied by evaluating the DNA elongation in square, rectangular, and triangular channels. We demonstrate that coupling electrostatically interacting walls with a triangular geometry is an efficient way to stretch DNA molecules at the scale of hundreds of nanometers. The paper reports experimental observations of λ-DNA molecules in poly(dimethylsiloxane) nanochannels filled with solutions of different ionic strength. The results are in good agreement with the theoretical predictions, confirming the crucial role of the electrostatic repulsion of the constraining walls on the molecule stretching.  相似文献   
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