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31.
This paper focuses on the perspectives of Years 7 and 8 Pasifika students on mathematics learning, in particular their views about the communication of solution strategies with others (their peers), and their teacher. Pasifika students' ideas about the importance of communicating their mathematical reasoning and strategies to peers and teachers were analysed and themes identified. While most students were in agreement about the importance of explaining their thinking to others, there was considerable variation in the reasons they gave for their views. The findings are interpreted in relation to socio-cultural theory and recent writing about requirements for citizenship in the twenty-first century.  相似文献   
32.
Surface features such as uneven playing surfaces, low impact absorption capacity and inappropriate friction/traction characteristics are connected with injury prevalence whereas force impact during foot strike has been suggested to be an important mechanism of intravascular haemolysis during running. We aimed to evaluate intravascular haemolysis during running and compare the effect of running on two different types of surfaces on haemolysis. We selected two surfaces (asphalt and grass) on which these athletes usually run. Participants were randomly assigned to group A (asphalt) or group B (grass) with 10 athletes in each group. Each athlete completed one hour of running at the calculated target heart rate (60-70%). Venous blood samples were collected before and immediately after running. We measured unconjugated bilirubin (UBR) (mg · dl(-1)), lactate dehydrogenase (LDH) (μ · ml(-1)), haemoglobin (g · l(-1)) and serum ferritin (ng · ml(-1)) as indicators of haemolysis. Athletes who ran on grass demonstrated an increase in the haematological parameters (UBR: P < 0.01, LDH: P < 0.05) when compared to athletes who ran on asphalt (UBR: P < 0.05, LDH: P = 0.241). Our findings indicate that intravascular haemolysis occurs significantly after prolonged running. Furthermore, we conclude that uneven grass surface results in greater haemolysis compared to asphalt road.  相似文献   
33.
In this study, a simple roller burnishing tool was made to operate burnishing processes on A356/5%SIC metal matrix composite fabricated by electromagnetic stir casting under different parameters. The effects of burnishing speed, burnishing force and number of burnishing passes on the surface roughness and tribological properties were measured. Scanning electron microscopy (SEM) graphs of the machined surface with PCD (insert-10) tool and roller burnished surface with tungsten carbide (WC) roller were taken into consider- ation to observe the surface finish of metal matrix composites. The mechanical properties (tensile strength, hardness, duc- tility) of A356/5%SIC metal matrix composites were studied for both unburnished samples and burnished samples. The results revealed that the roller burnished samples of A356/ 5%SIC led to the improvement in tensile strength, hardness and ductility. In order to find out the effects of roller bur- nishing process parameters on the surface roughness of A356/ 5%SIC metal matrix composite, response surface methodol- ogy (RSM) (Box-Behnken design) was used and a prediction model was developed relevant to average surface roughness using experimental data. In the range of process parameters, the result shows that roller burnishing speed increases, and surface roughness decreases, but on the other hand roller burnishing force and number of passes increase, and surface roughness increases. Optimum values of burnishing speed (1.5 m/s), burnishing force (50 N) and number of passes (2) during roller burnishing of A356/5%SIC metal matrix com- posite to minimize the surface roughness (predicted 1.232 μm) have been found out. There was only 5.03% error in the experimental and modeled results of surface roughness.  相似文献   
34.
Reactive oxygen species (ROS) formed in various metabolic reactions cause unlimited damage by attacking and oxidizing the macromolecules. An arsenal of antioxidant substances neutralizes these ROS at various sites of their metabolic cascade, and if disequilibrium exists between the pro and antioxidant system, oxidative stress persists. The present study was undertaken in schizophrenia, to highlight the response and role of some endogenous antioxidants viz. reduced glutathione (GSH), bilirubin, total proteins, albumin and uric acid in scavenging the ROS. The effect of severity of disease, age factor, and substance abuse was also studied. In all, 50 schizophrenics and 50 age and sex-matched controls were enrolled in the present study. Fasting blood samples were drawn for estimating malondialdehyde (MDA), GSH, bilirubin, total proteins, albumin and uric acid in both the groups. The results were statistically analyzed by Z-test and correlated using correlation coefficient (r). The study shows reduction in MDA levels and decline in the level of endogenous antioxidants, but within the normal range. Chronic schizophrenics were at a higher risk of oxidative stress and age and substance abuse seems to worsen the situation.  相似文献   
35.
This article reports on the third phase of a larger study that explored the perceptions of teachers about distributed leadership practices for inclusive education (IE) in primary schools involved in IE reform in Bangladesh. The Distributed Leadership Practice for Inclusive Education scale was developed specifically for this study to collect data. Participants for the present study were head teachers and teachers from 308 public primary schools. The results of this study indicate that teachers perceived that distributed leadership practices for IE were present in primary schools in Bangladesh. The findings indicate that teachers' perceptions about distributed leadership practices for IE have a significant positive correlation with their satisfaction about the implementation of IE policy.  相似文献   
36.
The purpose of this paper was to investigate Malaysian primary pre-service teachers’ perceptions of students’ disruptive behaviour and their self-reported strategies to prevent and to manage such behaviours. Results indicate that Malaysian pre-service teachers understand disruptive behaviours to be those that disrupt the learning and teaching process. They identified the cause of student disruptive behaviour as factors residing within the individual student. Pre-service teachers here reported preventative strategies in terms of changing teaching strategies and threats to use punishment. When addressing students’ disruptive behaviour, pre-service teachers reported that they would use one-to-one counselling with students and remove tokens or hold back rewards. A discussion regarding the implications for teacher education institutions and future research concludes this paper.  相似文献   
37.
ABSTRACT

Increasingly intense, multifaceted, and integrated forms of surveillance are a central feature of Western national security attempts to counter the violence of “Islamic terrorism.” However, there has been a lack of research examining contemporary regimes of surveillance as profoundly racialized. This study examines how counterterrorism efforts are underpinned by ill-conceived accounts of radicalization that preemptively construct Muslim migrants as a threat to national security, thereby justifying practices of mass surveillance that further propagate racist discourses of uncertainty and risk. We advance an analysis of a racialized surveillant assemblage, which is generative of mutable, algorithmically determined profiles of the Muslim-as-terrorist. Such a regime of mass surveillance effectively puts all Muslims under suspicion. We highlight that, paradoxically, mass data-mining operations stifle, rather than aid, the identification of actual terrorist threats. This conditions a paranoid surveillant racism, through which Muslim populations become modulated as an unknowable threat of death and destruction.  相似文献   
38.
Reflection is an important prerequisite to making meaning of new information, and to advance from surface to deep learning. Strategies such as journal writing and peer feedback have been found to promote reflection as well as deep thinking and learning. This study used an empirical design to investigate the interaction effects of peer feedback and blogging on college students' reflective thinking skills and their learning approaches. Forty-four first- and second-year undergraduate students participated in the study. Students kept blogs each week throughout a whole semester. Two journals were sampled at the beginning and end of the semester for each student. A repeated measure one-way ANOVA suggested that students' reflective thinking level increased significantly over time; however, peer feedback was found to negatively affect students' reflective thinking skills. The result of the study suggests more carefully designed uses in the future.  相似文献   
39.
Everybody is familiar with the ubiquitous term ‘species’. But what is a species? Undeniably, this is one of the most complex dilemmas in the history of biology. There is no other concept in biology as elementary yet controversial as the concept of species. In practice, a species is regarded as the fundamental unit of comparison in all biological disciplines like systematics, evolution, ecology, ethology, physiology, and genetics. However, little agreement exists in the scientific community regarding the nature of species, whether it is a real entity or a cultural artifact, its biological significance or how to delineate a species. This article is a review of the seemingly endless debate on the species concept and its implications.  相似文献   
40.
Serum antioxidant status and peroxidative stress was estimated in 30 pregnant women, their newborn infants and 25 non-pregnant women. Serum Ascorbic acid, α-tocopherol, retinol & β-carotene levels were found to be significantly reduced and peroxidative stress was significantly higher in mothers as compared to matched non-pregnant women. Newborn had significantly higher levels of ascorbic acid as compared to their mother but had significantly lower levels of lipid soluble vitamins. The peroxidative stress in newborn was found to be significantly less as compared to their mothers. A positive correlation of ascorbic acid and α-tocopherol levels between mother and newborn reflects that their status in mother does influence the newborn status.  相似文献   
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