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1.
Joint presentations of a conditioned stimulus (CS) and an unconditioned stimulus (US) strengthen the contingency between them, whereas presentations of one stimulus without the other degrade this contingency. For example, the CS can be presented without the US either before conditioning (CS–no US and then CS–US; latent inhibition) or after conditioning (CS–US and then CS–no US; extinction). In vertebrate subjects and several invertebrate species, a time lapse usually results in a return of the conditioned response, or spontaneous recovery. However, in land mollusks, spontaneous recovery from extinction has only recently been reported, and response recovery after latent inhibition has not been reported. In two experiments, using conditioned aversion to a food odor as a measure of learning and memory retention, we observed contingency degradation via latent inhibition (Experiment 1) and extinction (Experiment 2) in the common garden slug, Lehmannia valentiana. In both situations, the contingency degradation procedure successfully attenuated conditioned responding, and delaying testing by several days resulted in recovery of the conditioned response. This suggests that the CS–US association survived the degradation manipulation and was retained over an interval of several days. 相似文献
2.
Kristen di Gennaro 《Assessing Writing》2013,18(2):154-172
A growing body of literature in second-language writing suggests that the writing ability of international second language (L2) learners, who attend post-secondary education abroad after having completed high school in their home countries, and the so-called Generation 1.5 population, that is, L2 learners who enter post-secondary education after attending high school in the new country, differs. The present study provides much-needed empirical evidence concerning potential differences in the writing ability of these two groups. Many-facet Rasch measurement procedures were used to analyze learners’ writing scores in five components, based on a theoretical model of writing ability: grammatical, cohesive, rhetorical, sociopragmatic, and content control. Results revealed that the international learners performed better overall than the Generation 1.5 learners and that the two groups had opposing strengths and weaknesses in grammatical and sociopragmatic control. Language program administrators and practitioners can use these results when designing curricula addressing the needs of diverse groups of L2 learners. 相似文献
3.
Several researchers have suggested that the computer holds much promise as a tool for science teachers for use in their classrooms (Bork, 1979, Lunetta & Hofstein, 1981). It also has been said that there needs to be more research in determining the effectiveness of computer software (Tinker, 1983). This study compared the effectiveness of microcomputer simulated experiences with that of parallel instruction involving hands-on laboratory experiences for teaching the concept of volume displacement to junior high school students. This study also assessed the differential effect on students' understanding of the volume displacement concept using sex of the students as another independent variable. In addition, it compared the degree of retention, after 45 days, of both treatment groups. It was found that computer simulated experiences were as effective as hands-on laboratory experiences, and that males, having had hands-on laboratory experiences, performed better on the posttest than females having had the hands-on laboratory experiences. There were no significant differences in performance when comparing males with females using the computer simulation in the learning of the displacement concept. This study also showed that there were no significant differences in the retention levels when the retention scores of the computer simulation groups were compared to those that had the hands-on laboratory experiences. However, an ANOVA of the retention test scores revealed that males in both treatment conditions retained knowledge of volume displacement better than females. 相似文献
4.
It is well documented that students' exposure to science in the middle school is critical for their later selection of science courses, yet instruction time and course offerings in science during the middle school years are often limited. Out-of-School Science Experiences with funds from the National Science Foundation (DISE No. 07872) produced five short science courses intended for children in middle school grades (6, 7, and 8) and their parents that supplement normal science instruction based on topics that are integral to traditional science teaching. The courses were offered through Community Education programs and through informal science learning centers (e.g., zoos, museums, and planetariums). An added strength of the program is that it employs the family as a motivator and reinforcer in a cooperative learning venture. The study reported here is an attempt to determine participant reaction two to three years after having taken the courses, to the course experience, the influence that the courses had on subsequent learning behavior, and the relationship between parents and children. 相似文献
5.
A major reason for the lack of scientific and technological literacy in this country is the lack of emphasis on high-quality science education at the elementary school level. The National Science Board Commission on Precollege Education in Mathematics, Science, and Technology states in its report (1983) that formal study of science must be reinforced by a wide range of activities outside the school. Learning in the home appears to be an excellent way to enhance elementary school science programs. Students who study with their parents or whose parents are involved in school activities achieve more in school. This study describes and presents evaluation data for a program that encourages elementary school students and their parents to study science topics in a hands-on, inquiry fashion in their own homes. The analyses of the data indicate that the program is viewed very positively by both the students and their parents, that there are gender and grade-level differences in the students, and that the program seems to be more effective for girls, a group at risk for continuing in science. 相似文献
6.
Maddalena Boccia Francesca Vecchione Antonella Di Vita Simonetta D'Amico Cecilia Guariglia Laura Piccardi 《Child development》2019,90(2):462-470
Notwithstanding its well-established role on high-demanding spatial navigation tasks during adulthood, the effect of field dependence–independence during the acquisition of spatial navigation skills is almost unknown. This study assessed for the first time the effect of field dependence–independence on topographical learning (TL) across the life span: 195 individuals, including 54 healthy young-adults (age-range = 20–30), 46 teenagers (age-range = 11–14), and 95 children (age-range = 6–9) participated in this study. Field dependence–independence interacted with age in predicting TL. Also during childhood higher field independence was associated with better performances but not later in the life, that is, during adolescence and adulthood. This result suggests that field dependence–independence may have a role in fostering the acquisition of TL. 相似文献
7.
During the 1960s and 1970s a number of family learning projects evolved, most of which focused on pre-schoolers and their parents. The goal of some of these programs was to provide enjoyable, structured experiences in which parents and their children learned together. Recently, a number of institutions have been sponsoring enrichment science classes or learning experiences for parents and older children. The study described here is based on a project funded by the National Science Foundation (DISE No. 07872) which was attempting to show that it was possible to increase scientific literacy of two different age groups by simultaneously exposing parents and their middle school children to short courses in science. The project is an outgrowth of a study previously reported (Gennaro, Bullock, & Alden, 1980) carried out at the Minnesota Zoological Gardens. The study is based on data obtained during the first two years of the project and used various data gathering procedures such as the use of questionnaires, interviews, observations, and cognitive testing. It was found that children register for the courses primarily because of interest in the subject matter of the courses and that parents register because of their desire to nurture the child and the child's interest in the subject matter of the course. Both parents and children made significant gains in learning as measured by subject matter tests. Participants reported that the experience was both enjoyable and valuable. Children's attitudes toward their parents and the course were significantly higher if the children perceived a highly cooperative learning environment with their parents. Parents who scored in the medium or high range on the pretest had significantly more interactions with their children concerning information about course tasks than those who scored low on the pretest. 相似文献
8.
Alessandro Fornasiero Aldo Savoldelli Roberto Modena Gennaro Boccia Barbara Pellegrini Federico Schena 《Journal of sports sciences》2018,36(8):901-906
In the literature there is a lack of data about the development of top level athletes in cross-country mountain biking (XCO). The purpose of this study was to analyze anthropometric and physiological characteristics of some of the best XCO bikers aged between 13 and 16. The study involved 45 bikers (26 males and 19 females) belonging to a youth national team. The evaluations, consisting of anthropometric measures, incremental cycling tests (VO2max, PPO, P@RCP), and 30 s Wingate Tests (PMax, PMean), were conducted over a lapse of 4 years. Our findings showed in bikers, already at young age, a specific athletic profile advantageous for XCO performance. At the age of 16, just before entering the junior category and competing at international level, male and female bikers showed physiological values normalized to the body mass comparable to those reported in literature for high level athletes (VO2max>70 and >60 ml/kg/min, PPO >6.5 and >5.5 W/kg, respectively in males and females). The production of high power-to-weight ratios and high peaks of anaerobic power attests the presence of highly developed aerobic and anaerobic systems in young XCO cyclists reflecting the high physiological demand of this sport. 相似文献
9.
Most of the Peer-to-Peer search techniques proposed in the recent years have focused on the single-key retrieval. However, similarity search in metric spaces represents an important paradigm for content-based retrieval in many applications. In this paper we introduce an extension of the well-known Content-Addressable Network paradigm to support storage and retrieval of more generic metric space objects. In particular we address the problem of executing the nearest neighbors queries, and propose three different algorithms of query execution. An extensive experimental study on real-life data sets explores the performance characteristics of the proposed algorithms by showing their advantages and disadvantages. 相似文献
10.
Domenico Calcaterra Piergiulio Cappelletti Alessio Langella Vincenzo Morra Abner Colella Roberto de Gennaro 《Journal of Cultural Heritage》2000,1(4)
Piperno, a Late Quaternary magmatic rock cropping out on the eastern side of the Campi Flegrei (Italy), is probably the most important building stone of Naples, used over a time-span from at least the Roman age until the beginning of the 20th century. Despite its wide diffusion in the monumental architecture of Naples, very little is known about this rock, as regards its technical features, as well as the geological aspects. This paper aims at providing a first overall contribution towards a rediscovery of this long-time-used material, in view of careful restoration works, which nowadays at Naples only take into account the proper geological features of the stone in a few peculiar cases. Thus, it seems of extreme importance to understand the basic parameters of Piperno and, above all, its response to weathering agents. Main mineralogical, petrographical and engineering–geological properties are presented here for the first time, with specific reference to two sampling areas, located at Pianura and Soccavo, in the western sector of the Neapolitan urban area. As far as many of its physico–mechanical features are concerned, Piperno extends over a wide range of values, which allow different varieties of the rock to be identified. This preliminary result is seemingly in accordance with data from old historical literature, which stated the existence of six horizons in the Piperno formation. 相似文献