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221.
Perhaps the most pressing issue concerning teacher education and training since the end of the Second World War has been that of the role of theory—or principled reflection—in professional expertise. Here, although the main post-war architects of a new educational professionalism clearly envisaged a key role for theory—considering such disciplines as psychology, sociology and philosophy as indispensable for reflective practice—there are nevertheless well-rehearsed difficulties about crediting such disciplines with quite the (applied) role in educational practice of (say) physiology or anatomy in medical practice. This paper argues that while recent developments in professional teacher education and training may have moved on from erstwhile instrumentalist and/or applied science (competence and other) perspectives, there may yet be a case for further progress towards a rather more sophisticated philosophical psychology of teacher knowledge and expertise.  相似文献   
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Data driven pedagogy has been introduced into Australian schools over the last decade to improve student learning outcomes, but are teacher educators preparing preservice teachers to be data literate? We used a survey to investigate ready-to-graduate preservice teachers’ beliefs regarding their knowledge and skills in data literacy. Before entering a course on data literacy their belief responses indicated that they had basic data interpretation knowledge, but they were unsure of how to translate that knowledge into the classroom to improve student outcomes. The survey was administered again after a data literacy course, which included a five-week supervised professional experience task of observing data being used in schools to drive pedagogy. The post-course survey responses showed students increased confidence in their ability to interpret and use data, suggesting that a data literacy course linked to the professional experience task improves teachers’ sense of preparedness to use data in the classroom. Keywords: Data literacy; professional learning.  相似文献   
224.
Two different measurement techniques are used to examine the effect of surface geometry on soccer ball trajectories. Five professional players are observed using high-speed video when taking curling free kicks with four different soccer balls. The input conditions are measured and the average launch velocity and spin are found to be approximately 24 m/s and 106 rad/s. It is found that the players can apply more spin (~50%) on average to one ball, which has a slightly rougher surface than the other balls. The trajectories for the same four balls fired at various velocities and spin rates across a sports hall using a bespoke firing device are captured using high-speed video cameras, and their drag and lift coefficients estimated. Balls with more panels are found to experience a higher lift coefficient. The drag coefficient results show a large amount of scatter, and it is difficult to distinguish between the balls. Using the results in a trajectory prediction programme it is found that increasing the number of panels from 14 to 32 can significantly alter the final position of a 20 m-curling free kick by up to 1 m.  相似文献   
225.
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   
226.
We examine the North Carolina Pre-K (NC Pre-K) program to test the hypothesis that observed variation in effects resulting from exposure to the program can be attributed to interactions with other environmental factors that occur before, during, or after the pre-k year. We examine student outcomes in 5th grade and test interaction effects between NC's level of investment in public pre-k and moderating factors. Our main sample includes the population of children born in North Carolina between 1987 and 2005 who later attended a public school in that state, had valid achievement data in 5th grade, and could be matched by administrative record review (n = 1,207,576; 58% White non-Hispanic, 29% Black non-Hispanic, 7% Hispanic, 6% multiracial and Other race/ethnicity). Analyses were based on a natural experiment leveraging variation in county-level funding for NC Pre-K across NC counties during each of the years the state scaled up the program. Exposure to NC Pre-K funding was defined as the per-4-year-old-child state allocation of funds to a county in a year. Regression models included child-level and county-level covariates and county and year fixed effects. Estimates indicate that a child's exposure to higher NC Pre-K funding was positively associated with that child's academic achievement 6 years later. We found no effect on special education placement or grade retention. NC Pre-K funding effects on achievement were positive for all subgroups tested, and statistically significant for most. However, they were larger for children exposed to more disadvantaged environments either before or after the pre-k experience, consistent with a compensatory model where pre-k provides a buffer against the adverse effects of prior negative environmental experiences and protection against the effects of future adverse experiences. In addition, the effect of NC Pre-K funding on achievement remained positive across most environments, supporting an additive effects model. In contrast, few findings supported a dynamic complementarity model. Instrumental variables analyses incorporating a child's NC Pre-K enrollment status indicate that program attendance increased average 5th grade achievement by approximately 20% of a standard deviation, and impacts were largest for children who were Hispanic or whose mothers had less than a high school education. Implications for the future of pre-k scale-up and developmental theory are discussed.  相似文献   
227.
Know-how     
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This study examined the association between psychological climate and the types of communication relationships employees form with their peers. 194 teachers completed a questionnaire measuring psychological climate. They also reported their proportions of information, collegial and special peer relationships. Perceptions of the organization's climate were associated with the types of communication relationships employees form with their peers. These associations were moderated, in part, by gender, suggesting that men and women differ significantly in the ways they approach friendships at work. Implications of these findings are discussed.  相似文献   
230.
OBJECTIVE: This study aimed to profile subgroups of CSA cases referred for assessment at two national CSA assessment centers in Ireland. METHOD: Historical and clinical data for 150 CSA cases were drawn from records of two Dublin-based national specialist sexual abuse assessment and therapeutic centers. Three main comparisons were made involving: (1) 113 confirmed CSA cases and 37 unconfirmed CSA cases, (2) 55 confirmed CSA cases that displayed clinically significant behavior problems, and the 56 confirmed CSA cases without significant adjustment difficulties, and (3) 19 confirmed CSA cases in which violence was a central feature, and 79 confirmed cases in which violence was not a central feature. RESULTS: There were three main findings. (1) More unconfirmed cases were male; had single or separated parents; and a father with a criminal history. As a group, the confirmed cases were largely youngsters who had been abused by male adults or adolescents outside their nuclear family and who subsequently were well supported by one or two parents. (2) Poorly adjusted CSA victims had a history of coercive violent abuse while better adjusted children were victims of nonviolent abuse. (3) Victims of violent CSA were more likely to have experienced penetrative abuse and to display more externalizing behavior problems. CONCLUSIONS: Confirmed and unconfirmed CSA cases, well and poorly adjusted CSA cases, and victims of violent and nonviolent CSA referred for assessment at two national CSA assessment centers in Ireland had distinctive clinical profiles.  相似文献   
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