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41.
This paper explores how participants in a Swedish secondary school do gender talk with comics. Swedish schools are tasked with working with gender, but this can be a challenge for many teachers, and finding materials to work with gender aspects can be difficult. Meanwhile, literary research on comics has shown them to be a potential tool for problematising gender, but little educational research has investigated the gender discussions that comics can promote. Therefore, using conversation-analytical methodology, we have documented situated classroom talk through video observations, focusing on the social construction of gender. Five excerpts are shown, where different aspects of gender talk are displayed and discussed. Results indicate that although students deconstruct and criticise gendered binaries in characteristics and behaviour from comics' imagery, this critique remains superficial, revolving around the hypersexualised body imagery of the muscular superhero the Phantom or the outdated femininity of the girly Daisy Duck. Although comics present an opportunity for discussions of norm critique in the classroom, we suggest that more social-realistic comics, wherein gender roles are more subtle and nuanced, be used for furthering the research on this topic and allowing students more width when it comes to deconstructing gender binaries.  相似文献   
42.
Passive particle focusing based on inertial microfluidics was recently introduced as a high-throughput alternative to active focusing methods that require an external force field to manipulate particles. In inertial microfluidics, dominant inertial forces cause particles to move across streamlines and occupy equilibrium positions along the faces of walls in flows through straight micro channels. In this study, we systematically analyzed the addition of secondary Dean forces by introducing curvature and show how randomly distributed particles entering a simple u-shaped curved channel are focused to a fixed lateral position exiting the curvature. We found the lateral particle focusing position to be fixed and largely independent of radius of curvature and whether particles entering the curvature are pre-focused (at equilibrium) or randomly distributed. Unlike focusing in straight channels, where focusing typically is limited to channel cross-sections in the range of particle size to create single focusing point, we report here particle focusing in a large cross-section area (channel aspect ratio 1:10). Furthermore, we describe a simple u-shaped curved channel, with single inlet and four outlets, for filtration applications. We demonstrate continuous focusing and filtration of 10 μm particles (with >90% filtration efficiency) from a suspension mixture at throughputs several orders of magnitude higher than flow through straight channels (volume flow rate of 4.25 ml/min). Finally, as an example of high throughput cell processing application, white blood cells were continuously processed with a filtration efficiency of 78% with maintained high viability. We expect the study will aid in the fundamental understanding of flow through curved channels and open the door for the development of a whole set of bio-analytical applications.  相似文献   
43.
This study focused, for the first time, on the effect of ultrasonic features on the extraction efficiency of secondary metabolites in mustard seed cake(MSC). The nematostatic potential of sonicated seed cake was examined against the second-stage juveniles(J2 s) of root-knot nematode, Meloidogyne javanica. The results show that a 35 ppm(parts per million) concentration of a sonicated extract(SE) sample of MSC caused 65% J2 s mortality at 18 h exposure period in vitro. It also significantly suppressed the root-knot index(RKI=0.94) in tomato roots. The lethal concentration values for SE were 51.76, 29.79, and 13.34 ppm,respectively, at 6, 12, and 18 h of the exposure period, and the lethal concentration values for the non-sonicated extract(NSE)sample were 116.95, 76.38, and 55.59 ppm, respectively, at similar exposure time. Sinapine and gluconapin were identified as the major compounds in ultrasonic-assisted MSC. Because of the high extraction efficiency of metabolites in the SE, all treatments of SE were shown to be antagonistic to J2 s. Thus, this study of ultrasonication activity-based profiling of MSC may help generate target-based compounds at a scale relevant to the control of disease caused by nematodes in economic crops.  相似文献   
44.
Education and Information Technologies - In recent years, and also due to the COVID-19 pandemic, education institutions worldwide have changed their education paradigm from a traditional to an...  相似文献   
45.
The new Advanced Placement (AP) Computer Science (CS) Principles course increases the need for quality CS teachers and thus the need for professional development (PD). This article presents the results of a 2-year study investigating how teachers teaching the AP CS Principles course for the first time used online PD material. Our results showed that the teaching and computing background of teachers had a significant impact on the teachers' need for and use of online PD material. More specifically, novice CS teachers needed and used PD for developing their pedagogical content knowledge (PCK). Non-CS teachers needed and used PD materials emphasizing content knowledge. Experienced CS teachers believed they had little need for PD even though they were teaching a new course. Our study makes three recommendations for designing effective online PD for CS teachers: match PD to teachers' background, align PD with the course curriculum, and use effective motivational design to enhance teacher engagement. (Keywords: computer science education, online professional development, K–12, AP computer science principles course)  相似文献   
46.
The complexity of science teaching requires science teachers to encounter a range of tasks. Some tasks are perceived as stressful while others are not. This study aims to investigate the extent to which different teaching situations lead to different stress levels. It also aims to identify the easiest and most difficult conditions to be regarded as stressful conditions by science teachers. An occupational stress inventory of 25 items developed by Okebukola (1988) validation of the occupational stress inventory for science teachers. Science Teacher, was used to measure the science teachers’ stress level in science teaching. A four point Likert scale ranging from 1 – ‘no stress at all’ to 4 – ‘extreme stress’ was used. Fifty-eight Malaysian secondary science teachers participated in the survey in which six volunteered to participate in the interview study. The data was then analyzed using the Rasch model to measure the level of stress caused by different kinds of stressful conditions. Even though ‘overloaded science syllabus’ was identified to be the basis of multiple stressful conditions, it was, however, difficult for the respondents to regard it as a stressful condition. On the other hand, the respondents found that ‘having to teach difficult science topics’ is easiest to be regarded as a stressful condition. It was shown that even though ‘overloaded science syllabus’ is the starting point for stress caused by multiple conditions, due to the availability of coping strategies which can be employed by the respondents, the stressor is minor in causing stress among teachers. On the other hand, when teachers lack the availability of coping strategies dealing with teaching difficult science topics, they easily feel stressful. One of the main recommendations to overcome stressful conditions is to provide the science teachers ‘topic specific pedagogy’ during in-service training.  相似文献   
47.
Abstract

The aims of this study were to establish the physical and physiological attributes of elite and sub-elite Malaysian male badminton players and to determine whether these attributes discriminate elite players from sub-elite players. Measurements and tests of basic anthropometry, explosive power, anaerobic recovery capacity, badminton-specific movement agility, maximum strength, and aerobic capacity were conducted on two occasions, separated by at least one day. The elite (n = 12) and sub-elite (n = 12) players' characteristics were, respectively: mean age 24.6 years (s = 3.7) and 20.5 years (s = 0.7); mass 73.2 kg (s = 7.6) and 62.7 kg (s = 4.2); stature 1.76 m (s = 0.07) and 1.71 m (s = 0.05); body fat 12.5% (s = 4.8) and 9.5% (s = 3.4); estimated VO2max 56.9 ml · kg?1 · min?1 (s = 3.7) and 59.5 ml · kg?1 · min?1 (s = 5.2). The elite players had greater maximum absolute strength in one-repetition maximum bench press (P = 0.015) compared with the sub-elite players. There were significant differences in instantaneous lower body power estimated from vertical jump height between the elite and sub-elite groups (P < 0.01). However, there was no significant difference between groups in shuttle run tests and on-court badminton-specific movement agility tests. Our results show that elite Malaysian male badminton players are taller, heavier, and stronger than their sub-elite counterparts. The test battery, however, did not allow us to discriminate between the elite and sub-elite players, suggesting that at the elite level tactical knowledge, technical skills, and psychological readiness could be of greater importance.  相似文献   
48.
Whilst laboratory-on-chip cell separation systems using dielectrophoresis are increasingly reported in the literature, many systems are afflicted by factors which impede “real world” performance, chief among these being cell loss (in dead spaces, attached to glass and tubing surfaces, or sedimentation from flow), and designs with large channel height-to-width ratios (large channel widths, small channel heights) that make the systems difficult to interface with other microfluidic systems. In this paper, we present a scalable structure based on 3D wells with approximately unity height-to-width ratios (based on tubes with electrodes on the sides), which is capable of enriching yeast cell populations whilst ensuring that up to 94.3% of cells processed through the device can be collected in tubes beyond the output.  相似文献   
49.
An experimental machine vision apparatus was used to identify and extract recyclable plastic bottles out of a conveyor belt. Color images were taken with a commercially available Webcam, and the recognition was performed by our homemade software, based on the shape and dimensions of object images. The software was able to manage multiple bottles in a single image and was additionally extended to cases involving touching bottles. The identification was fulfilled by comparing the set of measured features with an existing database and meanwhile integrating various recognition techniques such as minimum distance in the feature space, self-organized maps, and neural networks. The recognition system was tested on a set of 50 different bottles and provided so far an accuracy of about 97% on bottle identification. The extraction of the bottles was performed by means of a pneumatic arm, which was activated according to the plastic type; polyethylene-terephthalate (PET) bottles were left on the conveyor belt, while non-PET bottles were extracted. The software was designed to provide the best compromise between reliability and speed for real-time applications in view of the commercialization of the system at existing recycling plants.  相似文献   
50.
Chlorella vulgaris (CV) has been reported to have antioxidant and anticancer properties. We evaluated the effect of CV on apoptotic regulator protein expression in liver cancer-induced rats. Male Wistar rats (200∼250 g) were divided into eight groups: control group (normal diet), CDE group (choline deficient diet supplemented with ethionine in drinking water to induce hepatocarcinogenesis), CV groups with three different doses of CV (50, 150, and 300 mg/kg body weight), and CDE groups treated with different doses of CV (50, 150, and 300 mg/kg body weight). Rats were sacrificed at various weeks and liver tissues were embedded in paraffin blocks for immunohistochemistry studies. CV, at increasing doses, decreased the expression of anti-apoptotic protein, Bcl-2, but increased the expression of pro-apoptotic protein, caspase 8, in CDE rats, which was correlated with decreased hepatoctyes proliferation and increased apoptosis as determined by bromodeoxy-uridine (BrdU) labeling and terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) assay, respectively. Our study shows that CV has definite chemopreventive effect by inducing apoptosis via decreasing the expression of Bcl-2 and increasing the expression of caspase 8 in hepatocarcinogenesis-induced rats. Project supported by Department of Biochemistry, Faculty of Medicine, UKM Medical Center, Universiti Kebangsaan Malaysia, and the Malaysian Ministry of Science and Technological Innovation (MOSTI)  相似文献   
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