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201.
Agriculture, industry and medicine are being altered by new biotechnologies. Biotechnology education is important because todays students and citizens will make decisions about the development and application of these new molecular biologies. This article reports an investigation of the teaching of biotechnology in an Australian state, New South Wales (NSW). In NSW few students were electing to answer examination questions related to biotechnology, suggesting that few students were studying the topic. This study looks at why electives relating to biotechnology are chosen or not chosen by students and teachers, with the intention of developing a greater understanding of the requirements for provision of a successful unit of study in this subject. Data was obtained through a survey of secondary science teachers, interviews with teachers and two case studies of the teaching of a biotechnology unit. Teachers reported a range of obstacles to the teaching of biotechnology including the difficulty of the subject matter and a lack of practical work that was suited to the content of the teaching unit. If biotechnology is worth learning in school science, then further research is needed to identify ways to promote the effective teaching of this topic, which teachers regard as important for, and interesting to, students but which most teachers choose not to teach. 相似文献
202.
One hundred and three children attending Learning Assistance Centres due to reading difficulties and one hundred and three matched, average readers were administered a battery of auditory perceptual processing tasks. The battery was composed of auditory analysis and synthesis, auditory sequential memory, auditory discrimination, and phonemic segmentation tasks. A principal components analysis yielded four factors. These were determined to be advanced phonological awareness, sequential memory, discrimination, and simple phonological awareness. Discriminant analyses, using the factor scores, indicated that three of the four factors were able to discriminate between the able and disabled readers. Most notable among these was advanced phonological awareness. Auditory discrimination could not discriminate between the groups. The results suggest that there may not be one underlying phonological ability implicated in successful reading acquisition. Furthermore, it is clear that two levels of phonological awareness exist and that screening and diagnostic instruments should address both in order to have predictive validity. 相似文献
203.
OBJECTIVE: This study examines the relationship between parental self-confidence, warmth, and involvement, and corporal punishment in families of children with attention deficit/hyperactivity disorder (ADHD). METHOD: The diagnosis of ADHD was established through clinical interviews with the parents, children, and teachers, according the criteria in DSM-IV-TR. This diagnosis was also established by having the parents complete the Conners' Parent Rating Scale, and the teachers complete the Conners' Teacher Rating Scale. Two groups of Iranian parents, one group with children who have ADHD (N=130) and a control group (N=120), completed questionnaires measuring parental self-confidence and parenting styles. RESULTS: Parents of children with ADHD were found to have lower self-confidence and less warmth and involvement with their children, and used corporal punishment significantly more than the parents of control children. CONCLUSIONS: The study provides strong evidence that children with ADHD are at considerable risk of abuse by their parents. Rather than focusing only on the child's ADHD, treatment may also need to address the parents' functioning. 相似文献
204.
Brown MF Knight-Green MB Lorek EJ Packard C Shallcross WL Wifall T Price T Schumann E 《Learning & behavior》2008,36(4):327-340
In two experiments using a radial-arm maze, pairs of rats made choices among eight maze locations, each containing a large
quantity of one of two food types. The choices made by 1 rat affected the choices made by the other rat. Under most conditions,
visits by 1 rat increased the tendency of the other rat to subsequently choose that maze location. However, the effect depended
on the quality of the food available in a particular location. When it was possible for the rats to observe each other on
the maze arms and a rat had experienced that a location contained the less preferred food type, a previous visit to that location
by the foraging partner decreased the tendency to visit that location. These effects are attributed to working memory for
the spatial choices of another rat, and they indicate that memory produced by a rat’s own visit to a maze location is integrated
with memory for the behavior of another rat to determine spatial choice 相似文献
205.
A. Mark Langan David M. Shuker W. Rod Cullen David Penney Richard F. Preziosi C. Philip Wheater 《Assessment & Evaluation in Higher Education》2008,33(2):179-190
There are many influences on how assessors grade themselves and others. Oral presentations are useful for exploring such factors in peer, self‐ and tutor marked assessments, being rapidly completed and assessed, commonly used in HE and very difficult to anonymize. This opportunistic study examined the effects of gender and level of attainment on the triangulation of marks awarded to student presenters. Grades generated by peer assessment were associated more strongly with tutor‐awarded marks than those from self‐assessment. For self‐assessment there was a strong effect of gender (female students undervalued their performance compared with tutor grades). Peer assessment produced higher marks than from tutors, perhaps because of the close‐knit community developed during residential courses. For tutor marks, the greatest variability was at the lower end of the scale, whereas peer assessors were most variable when marking students who self‐evaluated or peer assessed highly. Students awarded a narrower range of marks to peers compared with tutors, but when self‐assessing used a larger range. Presentations by students who admitted to little sleep the night before received lower grades from both peers and tutors, but this was not reflected by self‐assessments, suggesting they were unaware of their poorer performances. Sessions with fewer talks (four rather than seven) reduced the ‘dip’ in marks previously observed in the middle of sessions. Findings are discussed in the context of bias in this mode of assessment. 相似文献
206.
Christopher F. Lucey Sarah K. Y. Lam 《International journal for the advancement of counseling》2012,34(2):107-117
This study was designed to identify characteristics of family functioning that relate to suicide potential in an outpatient
adolescent population. Participants included 51 adolescents between the ages of 14 and 18 who were involved in outpatient
counselling. The Family Environment Scale and the Suicide Probability Scale were used to assess adolescents’ perception of
family social climate and degree of suicide risk respectively. Results revealed significant correlations between suicide risk
and family systems characterized by heightened conflict and lower levels of cohesion, independence, and organization. A stepwise
multiple regression analysis suggested that organization (related to clarity and structure in family activities and responsibilities)
was the strongest predictor of suicide risk. Implications for research and practice are considered. 相似文献
207.
Debasis?GangulyEmail authorView authors OrcID profile Gareth?J.?F.?Jones Aarón?Ramírez-de-la-Cruz Gabriela?Ramírez-de-la-Rosa Esaú?Villatoro-Tello 《Information Retrieval》2018,21(1):1-23
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents. 相似文献
208.
We present an overview of the special issue in this paper. The main objective is to provide information for lecturers on how
to improve the student experience, using current knowledge in the field. To this end we present an overview of six papers
covering areas as diverse as tools and methods used to support teaching and learning, pedagogical challenges in teaching mathematics
for search, etc. 相似文献
209.
Two rhesus monkeys were tested in 6- and 10-item list memory tasks for performance changes as a function of the exposure duration of the list stimuli and the interstimulus interval (ISI) between successive list stimuli. Accuracy increased with longer item exposure duration and tended to decrease with longer ISI duration. Humans, by contrast, typically show increases in accuracy with ISI, a result taken as evidence of rehearsal. The decrease in accuracy for monkeys suggests that they were not using rehearsal processes in these list memory experiments. Further tests in which choice accuracy with predictable ISIs was compared with choice accuracy with unpredictable ISIs also yielded no evidence of rehearsal by the monkeys. This apparent absence of rehearsal mechanisms in monkeys, in situations also shown to support human rehearsal, is discussed as a potential difference in the visual working memory processes of the two species. 相似文献
210.
Preschool teachers and classroom aides: Same context,similar perceptions of children's behaviors? 下载免费PDF全文
This study explored the correspondence and differences between school staff perceptions of preschool children's social skills and behavior problems. One hundred preschoolers were assessed by 14 pairs of teachers and classroom aides with the Preschool and Kindergarten Behavior Scales – 2nd Edition (PKBS‐2 Portuguese version). Indexes of agreement and disagreement were calculated. Risk levels and item analyses of PKBS‐2 scores according to both informants' ratings were compared. A higher level of agreement was obtained for social skills scores than for behavior problems (mean correlation of .62). No statistically significant differences between informants were obtained for the risk levels, and item analyses revealed a similar pattern of behaviors that were most and least rated by both informants. Results indicate that the classroom aides' perspective on preschool assessment represents a reliable input, which justifies that they network with teachers in addressing preschoolers' social‐emotional and behavioral challenges. 相似文献