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81.
How can we assess the opportunity that students have to learn the material they find on tests? How do students' perceptions of opportunity to learn differ from their teachers? 相似文献
82.
Eduardo Mercado Scott O. Murray Robert K. Uyeyama Adam A. Pack Louis M. Herman 《Learning & behavior》1998,26(2):210-218
Little is known about how animals represent their own actions in working memory. We investigated whether bottlenosed dolphins could recall actions they had recently performed and reveal those recollections using an abstract rule. Two dolphins were trained to respond to a specific gestural command by repeating the last behavior performed. Both dolphins proved to be able to repeat a wide variety of behaviors on command and were able to generalize the repeating rule to novel behaviors and situations. One dolphin was able to repeat all 36 behaviors she was tested on, including behaviors involving multiple simultaneous actions and self-selected behaviors. These results suggest that dolphins can flexibly access memories of their recent actions and that these memories are of sufficient detail to allow for reenactments. The repeating task can potentially be used to investigate short-term action and event representations in a variety of species. 相似文献
83.
84.
Patrick C.Y.WOO Samson S.Y.WONG Jade L.L.TENG Kit-Wah LEUNG Antonio H.Y.NGAN Herman TSE Susanna K.P.LAU Kwok-Yung YUEN 《Journal of Zhejiang University. Science. B》2010,11(6):391-401
A straight, non-sporulating, Gram-variable bacillus (HKU24T) was recovered from the blood culture of a patient with metastatic breast carcinoma. After repeated subculturing in BACTEC Plus Anaerobic/F blood culture broth, HKU24T grew on brucella agar as non-hemolytic, pinpoint colonies after 96 h of incubation at 37 °C in an anaerobic environment and aerobic environment with 5% CO2. Growth was enhanced with a streak of Staphylococcus aureus. HKU24T was non-motile and catalase-negative, but positive for alkaline phosphatase, β-glucosidase, and α-glucosidase. It hydrolyzed phenylphosphonate and reduced resazurin. 16S rRNA, groEL, gyrB, recA, and rpoB sequencing showed that HKU24T occupies a distinct phylogenetic position among the Leptotrichia species, being most closely related to Leptotrichia trevisanii. Using HKU24T groEL, gyrB, recA, and rpoB gene-specific primers, fragments of these genes were amplified from one of 20 oral specimens. Based on phenotypic and genotypic characteristics, we propose a new species, Leptotrichia hongkongensis sp. nov., to describe this bacterium. 相似文献
85.
This paper approaches the issue of higher entrepreneurship education in motivating young people to start their own business as a viable alternative to the successful integration of university graduates on the labour market. The fundamental question of this research is if, currently, entrepreneurship education influences students’ entrepreneurial intentions and to what extent. The research results, based on the statistical analysis of data collected through a questionnaire distributed to Romanian business and engineering bachelor students in the final year, highlight that business students assessed the effectiveness of higher entrepreneurship education and its positive influence on entrepreneurial intentions to a greater extent than the engineering students. Furthermore, entrepreneurial intentions of engineering students are influenced positively much more by entrepreneurial family background than by entrepreneurship education. The findings provide important highlights for future research, in order to identify the most effective ways of approaching, modernising and expanding entrepreneurship education, aiming to increase entrepreneurial intentions among students, regardless of the graduated field of study. 相似文献
86.
Robert S.Herman 《海外英语》2003,(2):4-6
Dear Friends,I recently learned that February 14th is celebrated inChina as qing ren jie.In America we call this Valentine’sDay and dedicate it to romantic love.Because of this I havebeen asked to devote this month’s column to Love.This is avery complicated subject,and not easy to write about.Thereare no experts.Terms are ambiguous,and there are wide cu-tural differences in our approach to the subject of Love. 相似文献
87.
Joan L. Herman Davina C.D. Klein Sara T. Wakai 《Assessment in Education: Principles, Policy & Practice》1997,4(3):339-352
This study used the 1993 California Learning Assessment System (CLAS) Middle Grades Mathematics Performance Assessment as a platform to examine alternative assessment in actual practice in the United States. Reported here is information gathered using the CLAS regarding student attitudes and approaches toward this new type of assessment. At issue is whether students find alternative assessments to be more motivating and interesting than traditional types of tests, and whether they appreciate the difference between traditional and alternative tasks. Data were collected in 13 schools across the state of California, involving more than 800 students. Instrumentation used in data collection included student surveys as well as in‐depth student retrospective interviews. Findings suggest that students do indeed understand the differences in approaches necessitated by novel, open‐ended versus more familiar multiple‐choice tasks. In addition, student attitudes toward these two types of tasks are discussed in detail. 相似文献
88.
Sanju Jalla Sunil Sazawal Salkat Deb robert E. Black Satya Narayan Das Archana Sarkar Maharaj K. Bhan 《Indian journal of clinical biochemistry : IJCB》2004,19(2):95-99
Lymphocyte subset estimations by flow cytometry in population-based studies require transportation of samples from the field
site to the laboratory. As samples arrive late in the day they have to wait overnight before being processed. The effect of
two possible approaches, sample storage for 24 h before staining and immediate staining with analysis after 24 h and 48 h
were evaluated. Two sets of experiments were performed with EDTA (ethylenediamine tetra-acetate) anticoagulated peripheral
blood. In the first experiment, after collection, each sample was divided into two portions. One portion was stained at the
time of blood collection and the other 24 h later after keeping it at room temperature (38–45°C). In the second experiment,
blood samples were stained within 1–2 h. Each sample was analyzed immediately upon completion of staining process and subsequently
after 24 h and 48 h of storage at 4°C. Results suggest that blood collected in EDTA can be processed using whole blood lysis
method, after storage at room temperature (38–45°C) for 24 h with some but not significant alteration in T-cell subsets. Storage
at 4°C after staining for 24 h results in a lesser and insignificant loss of cells or alteration of T-cell subsets and may
be the method of choice. 相似文献
89.
Sanju Jalla Sunil Sazawal Saikat Deb Robert E. Black Maharaj K. Bhan 《Indian journal of clinical biochemistry : IJCB》2002,17(1):69-74
The development of monoclonal antibodies combined with flow cytometry has revolutionized the analysis of lymphocyte subsets.
These newer methods using the Q-prep leucocyte preparation system require only 1–2 ml of blood as compared to 10 ml required
traditionally. One of the main impediments in the use of this superior technology in Indian laboratories has been the high
cost of reagents. This study evaluated methods to reduce the cost of assays. In the first experiment from 26 healthy subjects,
2ml venous blood samples in EDTA (ethylenediamine tetra-acetate) were obtained. Each sample was divided into two equal portions,
one portion was stained using diluted monoclonal antibody, whereas the other portion was stained using standard concentrations
of antibodies. In the second experiment, blood samples from 12 subjects were again divided into 2 portions; one portion of
each pair was processed using commercial Q-prep reagents while the other portion was processed using our own reagents. In
the first experiment, which evaluated use of a diluted antibody against the standard recommended concentrations, a 5-tube
panel that estimated CD3, CD4, CD8, CD20 was used. In the second experiment CD3, CD4 and CD8 were estimated. The total cost
per sample for a 5-panel estimation was however reduced from $39.11 to $1.10.
Given the proven advantages of using a whole blood stain-lyse method for T cell subset estimations, its use should be encouraged
in developing country settings. With the suggested methods the whole blood Q-prep could be performed at appreciably reduced
costs, without loss in precision. 相似文献
90.
This essay examines some ethical aspects of stalkingincidents in cyberspace. Particular attention is focused on the Amy Boyer/Liam Youens case of cyberstalking, which has raised a number of controversial ethical questions. We limit our analysis to three issues involving this particular case. First, we suggest that the privacy of stalking victims is threatened because of the unrestricted access to on-linepersonal information, including on-line public records, currently available to stalkers. Second, we consider issues involving moral responsibility and legal liability for Internet service providers (ISPs) when stalking crimesoccur in their `space' on the Internet. Finally, we examine issues of moral responsibility for ordinary Internet users to determine whether they are obligated to inform persons whom they discover to be the targets of cyberstalkers. 相似文献