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排序方式: 共有31条查询结果,搜索用时 171 毫秒
1.
This study compared the Qualitative Scoring System for the modified version of the Bender-Gestalt Test and the Developmental Scoring System for the Bender-Gestalt Test in predicting performance on the Metropolitan Achievement Test. The subjects were 409 first through fourth graders from regular classes in a public elementary school. Both scoring systems correlated significantly with school achievement. However, the Qualitative system correlated higher than the Developmental system with all Metropolitan Achievement Test subscores. Tests for differences between correlations indicated that five of these comparisons were statistically significant.  相似文献   
2.
Krull  Wilhelm 《Minerva》2004,42(1):29-39
Since the late 1980s, Europe has witnesseddramatic changes in the political landscape andin daily life. Many of these changes are drivenby new developments in science and technology.At the same time, research choices are beingmade in the anticipation of economic benefits.In this context, the European Commission andprivate foundations in Europe are rethinkingtheir approaches and priorities. This paperconsiders some of the changes taking place inresearch policy, and reflects upon somereconfigurations currently underway.  相似文献   
3.
In this work a disposable, parallel microbioreactor (MBR) suitable for screening in batch or continuous mode is presented. The reactor consists of five parallel microchambers made of poly(dimethylsiloxane) bonded to a glass substrate. A grid structure is engraved on each chamber, allowing subsequent morphology imaging. Measurements are recorded over the entire cultivation period with constant parameters, namely, position and focus in the z-axis. The microdevice may be used for either parallel, uni- or multiparametric screening, and overcomes the drawback of gridless microwell plates which require expensive equipment such as an inverted microscope with an automatic stage. To validate the scalability from laboratory scale to microscale, and thus the cultivation protocol in the MBR, the germination of fungal spores (A. ochraceus) is evaluated for two different key magnitudes (pH and temperature) and compared to the results obtained from conventional laboratory scale systems (flasks and agar plates). Information on germination capacity with regard to interspecies' variability allows for optimization of industrial processes as optimal pH and temperature matched to the mesoscopic cultivation systems. The germination conditions therefore remain unaffected inside the MBR, while providing the following advantages: (i) dramatic reduction of medium consumption, (ii) submerged cultivation with constant oxygen supply, (iii) assured low cost and disposability, and (iv) possibility of a continuous cultivation mode.  相似文献   
4.
This paper presents a vertically positioned microfluidic system made of poly(dimethylsiloxane) (PDMS) and glass, which can be applied as a microbubble column (μBC) for biotechnological screening in suspension. In this μBC, microbubbles are produced in a cultivation chamber through an integrated nozzle structure. Thus, homogeneous suspension of biomass is achieved in the cultivation chamber without requiring additional mixing elements. Moreover, blockage due to produced carbon dioxide by the microorganisms—a problem predominant in common, horizontally positioned microbioreactors (MBRs)—is avoided, as the gas bubbles are released by buoyancy at the upper part of the microsystem. The patterned PDMS layer is based on an optimized two-lithographic process. Since the naturally hydrophobic PDMS causes problems for the sufficient production of microbubbles, a method based on polyelectrolyte multilayers is applied in order to allow continuous hydrophilization of the already bonded PDMS-glass-system. The μBC comprises various microelements, including stabilization of temperature, control of continuous bubble formation, and two optical configurations for measurement of optical density with two different sensitivities. In addition, the simple and robust application and handling of the μBC is achieved via a custom-made modular plug-in adapter. To validate the scalability from laboratory scale to microscale, and thus to demonstrate the successful application of the μBC as a screening instrument, a batch cultivation of Saccharomyces cerevisiae is performed in the μBC and compared to shake flask cultivation. Monitoring of the biomass growth in the μBC with the integrated online analytics resulted in a specific growth rate of 0.32 h−1, which is almost identical to the one achieved in the shake flask cultivation (0.31 h−1). Therefore, the validity of the μBC as an alternative screening tool compared to other conventional laboratory scale systems in bioprocess development is proven. In addition, vertically positioned microbioreactors show high potential in comparison to conventional screening tools, since they allow for high density of integrated online analytics and therefore minimize time and cost for screening and guarantee improved control and analysis of cultivation parameters.  相似文献   
5.
This study investigates changes in the conceptions of learning and teaching among undergraduate student teachers. A qualitative content analysis of essays using metaphors to describe learning and teaching written by 256 students at the beginning and end of an educational psychology course was used as the main research procedure. It was found that there was an increase in the share of students that see learning and teaching from a cognitive-constructivist perspective and a decrease in the share that see learning and teaching from a behaviourist perspective by the end of the course. In addition, the study revealed that the coherence in the nature of the metaphors describing learning and teaching increased by the end of the course. However, there was practically no increase in the number of essays describing learning from a socio-constructivist perspective, a fact that points to a need to pay more attention to the manifestations of learning in different communities of students, that is, to a relevant knowledge that teachers need in their everyday work.  相似文献   
6.
Perinatal pain can be experienced by both mothers and infants. In this column, the author encourages readers to view an article by Gayle Page featured in this issue of the journal. Page's article shows the importance of protecting infants from unnecessary pain. The column author also points out that birth stories show the benefit of supporting women as they meet the challenges of a normal birth.  相似文献   
7.
Play power     
These games are excerpted from Play Poweravailable from Play Power Publishing, P.O. Box 2186, Orinda, CA 94563.  相似文献   
8.
Polyelectrolyte multilayers (PEMs) based on the combinations poly(diallyldimethylammonium chloride)∕poly(acrylic acid) (PDADMAC∕PAA) and poly(allylamine hydrochloride)∕PAA (PAH∕PAA) were adsorbed on poly(dimethylsiloxane) (PDMS) and tested for nonspecific surface attachment of hydrophobic yeast cells using a parallel plate flow chamber. A custom-made graft copolymer containing poly(ethylene glycol) (PEG) side chains (PAA-g-PEG) was additionally adsorbed on the PEMs as a terminal layer. A suitable PEM modification effectively decreased the adhesion strength of Saccharomyces cerevisiae DSM 2155 to the channel walls. However, a further decrease in initial cell attachment and adhesion strength was observed after adsorption of PAA-g-PEG copolymer onto PEMs from aqueous solution. The results demonstrate that a facile layer-by-layer surface functionalization from aqueous solutions can be successfully applied to reduce cell adhesion strength of S. cerevisiae by at least two orders of magnitude compared to bare PDMS. Therefore, this method is potentially suitable to promote planktonic growth inside capped PDMS-based microfluidic devices if the PEM deposition is completed by a dynamic flow-through process.  相似文献   
9.
Sexually transmitted infections (STIs) have risen among older people in Australia and other countries. To guide future initiatives, we examined sources of information that older people use or are willing to use for knowledge about safer sex and STIs, including whether there are any gender differences. A total of 2137 Australian adults aged 60+ years completed a nationwide survey. Analyses focused on participants who were at risk of an STI (n = 686; 220 women and 466 men). Overall, information-seeking on STIs in the last year was low (18% men; 15% women). When sought, common sources included general media outlets (e.g., magazines, TV), healthcare providers (HCPs), and the Internet. HCPs were the most relied upon source among both women and men. Brochures, websites, and HCPs were rated highest as future sources; however, women indicated they were more willing than men to have information provided by brochures and websites. STI information-seeking was generally low, but there was willingness among both men and women to use a range of sources for gaining future information.  相似文献   
10.
This study was aimed at investigating differences between novice and experienced teachers’ perceptions of planning activities for developing teacher education students’ professional skills by focusing on promoting of identified ill-developed skills. The teachers’ thinking about instructional planning was conceived as teachers’ decision-making for implementing primary teaching tasks in the planning, delivery, and reflective phases of instruction. This model served as a basis (or framework) for the identification of potential variables of planning skills and developing of items for a teachers’ questionnaire. Fifty-eight experienced and 55 novice teachers from Estonian schools of general education were surveyed. It was revealed that novice teachers did not apprehend events that may undermine reaching long-term instructional objectives and they focused more on the achievement of immediate objectives and the teaching of obligatory content in comparison with experienced teachers.  相似文献   
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