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The Special Education Elementary Longitudinal Study data set was utilised to examine the potential influences on placement decisions for students with multiple disabilities in the US. The sample consisted of 415 students. Specifically, the study investigated whether factors including students’ prior special education experiences, parental involvement, parental expectations and educational risk factors explain the placement of students in classrooms. Results indicate significant relations between the explanatory variables and the hours spent daily in general education classrooms. However, only two variables, parents’ education and receipt of early childhood special education services, were significantly associated with the dichotomised outcome of whether or not a child received any academic instruction in a general education classroom. Research limitations and implications for future research, policy and practice in the international context are discussed.  相似文献   
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A standard genetic/bioinformatic activity in the genomics era is the identification within DNA sequences of an "open reading frame" (ORF) that encodes a polypeptide sequence. As an educational introduction to such a search, we provide a webapp that composes, displays for solution, and then solves short DNA exemplars with a single ORFTo the Editor: We wish to bring a new Web resource to the attention of CBE—Life Sciences Education readers.When being introduced to the central dogma of nucleic acid transactions, students are often required to identify the 5′→3′ DNA template strand in a double-stranded DNA (dsDNA) molecule; transcribe an antiparallel, complementary 5′→3′ mRNA; and then translate the mRNA codons 5′→3′ into an amino acid polypeptide by means of the genetic code table. Although this algorithm replicates the molecular genetic process of protein synthesis, experience shows that the series of left/right, antiparallel, and/or 5′→3′ reversals is confusing to many students when worked by hand. Students may also obtain the “right” answer for the “wrong” reasons, as when the “wrong” DNA strand is transcribed in the “wrong” 3′→5′ direction, so as to produce a string of letters that “translates correctly.”In genetics and bioinformatics education, we have found it more intuitively appealing to demonstrate and emphasize the equivalence of the mRNA to the DNA sense strand complement of the template strand. The sense strand is oriented in the same 5′→3′ direction and has a sequence identical to the mRNA, except for substitution of thymidine in the DNA for uracil in the mRNA. It is thus more computationally efficient to “read” the polypeptide sequence directly from this strand, with mental substitution of thymidine in the triplets of the genetic code table. (By definition, “codons” occur only in mRNA: the equivalent three-letter words in the DNA sense strand may be designated “triplets.”) This is the same logic used in DNA “translation” software programs.A further constraint often imposed on dsDNA teaching exemplars is that five of the six possible reading frames are “closed” by the occurrence of one or more “stop” triplets, and only one is an open reading frame (ORF) that encodes an uninterrupted polypeptide. We designate this the “5&1” condition. The task for the student is to identify the ORF and “translate” it correctly. Other considerations include correct labeling of the sense and template DNA strands, their 5′ and 3′ ends (and of the mRNA as required), and the amino (N) and carboxyl (C) termini of the polypeptide.Thus, instructors face the logistical challenge of creating dsDNA sequences that satisfy the “5&1” condition for homework and exam questions. Instructors must compose sequences with one or more “stops” in the three overlapping read frames of one strand, while simultaneously creating two “stopped” frames and one ORF in the other. We have explored these constraints as an algorithmic and computational challenge (Carr et al., 2014 ). There are no “5&1” exemplars of length L ≤ 10, and the proportion of exemplars of length L ≥ 11 is very small relative to the 4L possible sequences (e.g., 0.0023% for L = 11, 0.048% for L = 15, 0.89% for L = 25). This makes random exploration for such exemplars inefficient.We therefore developed a two-stage recursive search algorithm that samples 4L space randomly to generate “5&1” exemplars of any specified length L from 11 ≤ L ≤ 100. The algorithm has been implemented as a Web application (“RandomORF,” available at www.ucs.mun.ca/~donald/orf/randomorf). Figure 1 shows a screen capture of the successive stages of the presentation. The application requires JavaScript on the computer used to run the Web browser.Open in a separate windowFigure 1.Successive screen captures of the webapp RandomORF. First panel: the Length parameter is the desired number of base pairs. Second panel: Clicking the “Generate dsDNA” button shows the dsDNA sequence to be solved, with labeled 5′ and 3′ ends. The button changes to “Show ORF.” Third panel: A second click shows the six reading frames, with the ORF highlighted. Here, the ORF is in the sixth reading frame on the bottom (sense) strand. The polypeptide sequence, read right to left, is N–EITHLRL–C, where N and C are the amino and carboxyl termini, respectively. The conventional IUPAC single-letter abbreviations for amino acids are centered over the middle base of the triplet; stop triplets are indicated by asterisks (*).The webapp provides a means for students to practice identifying ORFs by efficiently generating many examples with unique solutions (Supplemental Material); this can take the place of the more standard offering of a small number of set examples with an answer key. The two-stage display makes it possible for problems to be worked “cold,” with the correct ORF identified only afterward. For examinations, any exemplar may be presented in any of four ways, by transposing the top and bottom strands and/or reversing the direction of the strands left to right. Presentation of the 5′ end of the sense strand at the lower left or upper or lower right tests student recognition that sense strands are always read in the 5′→3′ direction, irrespective of the “natural” left-to-right and/or top-then-bottom order. We intend to modify the webapp to include other features of pedagogical value, including constraints on [G+C] composition and the type, number, and distribution of stop triplets. We welcome suggestions from readers.  相似文献   
244.
University instructors’ classroom assessments play a central role in and inevitably influence their teaching and their students’ learning. This paper reports on a comparative interview study conducted in a range of three ESL/EFL university contexts in Canada, Hong Kong and China. Six major aspects of ESL/EFL classroom assessment practices were explored: instructors’ assessment planning for the courses they taught, the relative weight given to course work and tests in their instruction, the type of assessment methods (selection vs. supply methods) that they used, the purposes each assessment was used for, the source of each method used, and when they used each method. University instructors were also asked to indicate what they saw as the advantages and disadvantages of the methods they used, and whether they took into account prior student knowledge when making decisions about what assessment methods to use. The findings contribute to a better understanding of ESL/EFL university instructors’ classroom assessment practices at the tertiary level in a range of three ESL/EFL university teaching contexts.  相似文献   
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Approaches to mentoring junior faculty in counselor education departments have received minimal attention in the counseling literature. In this article, the authors describe a successful program based on the 10 principles for good mentoring recommended by Sorcinelli (2000). Application of the principles within a combined formal and informal mentoring approach is described, as are the experiences of junior faculty whose careers have been shaped within this system.  相似文献   
247.
Research Findings: Outdoor play is important for children’s health and development, yet many preschool-age children in child care settings do not receive the recommended 60 min/day of outdoor play. Child care providers have previously described parent-related barriers to increasing outdoor playtime, including parents not providing appropriate clothing for their children and parents’ preference for academics over active play. This study explored parent perceptions and knowledge of outdoor playtime in child care environments. On average, parents reported wanting their child to spend significantly more time playing outside during a full day of child care than the recommended minimum. However, more than half of parents reported that they did not know how much time their child actually spent playing outside, and 43% reported that they did not know their child care center’s outdoor play policies. Practice or Policy: Child care providers may overperceive parent-related barriers to outdoor play. Parents generally support outdoor play for their preschooler during center-based child care but are not well informed about outdoor playtime and policies. Encouraging communication between parents and early childhood educators about these topics could lead to more universal support and strategies for promoting outdoor and active play opportunities for children, which are important for children’s health and development.  相似文献   
248.
Four experiments were performed to explore the role of context in operant extinction. In all experiments, leverpressing in rats was first reinforced with food pellets on a variable interval 30-s schedule, then extinguished, and finally tested in the same and a different physical context. The experiments demonstrated a clear ABA renewal effect, a recovery of extinguished responding when conditioning, extinction, and testing occurred in contexts A, B, and A, respectively. They also demonstrated ABC renewal (where conditioning extinction and testing occurred in contexts A, B, and C) and, for the first time in operant conditioning, AAB renewal (where conditioning, extinction, and testing occurred in contexts A, A, and B). The latter two phenomena indicate that tests outside the extinction context are sufficient to cause a recovery of extinguished operant behavior and, thus, that operant extinction, like Pavlovian extinction, is relatively specific to the context in which it is learned. AAB renewal was not weakened by tripling the amount of extinction training. ABA renewal was stronger than AAB, but not merely because of context A’s direct association with the reinforcer.  相似文献   
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This study describes the development of an instrument to investigate elementary students attitudes toward science. As a result of the instrument development process employed, the finalized instrument consisted of 28-items separated into three dimensions. The instrument was found to exhibit acceptable ranges of internal consistency. Confirmatory Factor Analysis showed three factors that clustered into the three dimensions of attitude identified and concurrent validity was evidenced as correlations were found when comparing attitude measures with the instrument to students?? perceptions of their science classrooms. Based on the analyses completed, the instrument appears to be useful for assessing student attitude toward science.  相似文献   
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