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991.
In this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (IBDV) by binary ethylenimine (BEI) in comparison with formalin, IBDV was isolated from the bursa of infected chickens and its confirmation was done by agar gel precipitation test. Viral suspensions were subjected to inactivation with BEI and formalin for pre-set time in- tervals. BEI was employed at concentrations of 0.001 and 0.002 mol/L while formalin was used at 0.1% and 0.2%. Sampling was done at 6, 12, 24, 36 and 48 h of incubation and samples were tested for their inactivation status in 9-day-old embryonated eggs and 3-week-old broiler chickens. IBDV was completely inactivated by 0.001 and 0.002 mol/L BEI after 36 h of incubation at 37℃, whereas formalin at 0. 1% and 0.2% concentrations inactivated IBDV in 24 h.  相似文献   
992.
A group of non-native, early signing deaf children between the ages of 7 and 11 years were tested on a referential communication task. A group of hearing children matched for sex and mental and chronological age were also included in the study. The aim was to study the deaf children's ability to take another persons perspective in a task that resembled a real-life communicative situation to a higher extent than the standard theory of mind (ToM) tasks. A further aim was to investigate the possible importance of a number of background variables such as mental and chronological age, working memory, and false-belief attribution. Results show that the hearing children outperformed the deaf children on the referential communication task and that results were highly correlated with both chronological and mental age, as well as with working memory. There was a positive, but not significant, correlation between false belief and success on the referential communication task. This is an indication that the two tasks tap different abilities and that false belief might be necessary, but not sufficient in order to be skilled in the art of referential communication. The possible role of working memory in the referential communication task is also discussed. The results support the hypothesis of the importance of early talk about mental states for the later development of ToM abilities.  相似文献   
993.
In this article, themost relevant literature on cognitive aging and instructional design is merged to formulate recommendations for designing computer-based training material aimed at elderly learners. The core message is that researchers and instructional designers do not need to develop special computerized instruction for older adults. Rather, existing principles of general instructional and multimedia design can be evaluated and used to accommodate the needs of elderly learners. Particular attention is given to John Sweller’s Cognitive Load Theory (CLT) and Richard Mayer’s Cognitive Theory of Multimedia Learning (CTML). It is argued that these instructional theories bear important benefits for older learners because they support an efficient use of available cognitive resources. New research directions are suggested to test the implications of these theories for learning in old age.
Pascal W. M. Van GervenEmail:
  相似文献   
994.
Rats experienced a spatial pattern of baited and unbaited arms in an eight-arm radial maze. The spatial pattern remained constant over trials, but the spatial locations that were baited varied unpredictably. Although there was no evidence of control by the spatial pattern during free choice training trials, the rats’ ability to locate baited arms in forced choice test trials was superior to that of animals in a control condition for which maze arms were not baited in a consistent spatial pattern. This is consistent with the results of experiments showing that spatial choices by rats in a pole box maze are controlled by abstract spatial patterns.  相似文献   
995.
OBJECTIVE: The current study examined the prevalence and characteristics of childhood sexual abuse in a jailed-based population. METHODOLOGY: A retrospective, self-reported survey was administered over an 8-week period to a random sample of 100 men who were incarcerated in a county jail in Southeastern Texas. The survey included questions about childhood sexual experiences before and after puberty, drug history and use, and sexual risk-taking behaviors. RESULTS: Of the 100 male inmates who participated in this study, 59% reported experiencing some form of sexual abuse before puberty, and all such instances occurred before or at the age of 13 years. The first episode of childhood sexual abuse began at an average age of 9.6 years (SD = 2.4), and ended at an average age of 13.0 years (SD = 2.3). Kissing and touching without intercourse (64%) was the common pattern of sexual abuse experience reported. The total number of perpetrators was 165, with 10% male and 90% female. Friends (n = 72) and family (n = 56) were the most frequent perpetrators. CONCLUSION: Childhood sexual abuse may be more prevalent among inmates than among males in the general population. These results show a high percentage of inmates who report a history of childhood sexual abuse; this rate is higher than those reported by other studies for incarcerated males. The findings support the belief held by professionals in the criminal justice field that a significant number of incarcerated males may have been victims of sexual abuse.  相似文献   
996.
The double-deficit hypothesis of dyslexia posits that reading deficits are more severe in individuals with weaknesses in phonological awareness and rapid naming than in individuals with deficits in only one of these reading composite skills. In this study, the hypothesis was tested in an adult sample as a model of reading achievement. Participants were parents of children referred for evaluation of reading difficulties. Approximately half of all participants reported difficulty learning to read in childhood and a small subset demonstrated ongoing weaknesses in reading. Structural equation modeling results suggest that the double-deficit hypothesis is an accurate model for understanding adult reading achievement. Better reading achievement was associated with better phonological awareness and faster rapid automatized naming in adults. Posthoc analyses indicated that individuals with double deficits had significantly lower reading achievement than individuals with single deficits or no deficits.  相似文献   
997.
College-level biology courses contain many complex processes that are often taught and learned as detailed narratives. These processes can be better understood by perceiving them as dynamic systems that are governed by common fundamental principles. Conservation of matter is such a principle, and thus tracing matter is an essential step in learning to reason about biological processes. We present here multiple-choice questions that measure students' ability and inclination to trace matter through photosynthesis and cellular respiration. Data associated with each question come from students in a large undergraduate biology course that was undergoing a shift in instructional strategy toward making fundamental principles (such as tracing matter) a central theme. We also present findings from interviews with students in the course. Our data indicate that 1) many students are not using tracing matter as a tool to reason about biological processes, 2) students have particular difficulties tracing matter between systems and have a persistent tendency to interconvert matter and energy, and 3) instructional changes seem to be effective in promoting application of the tracing matter principle. Using these items as diagnostic tools allows instructors to be proactive in addressing students' misconceptions and ineffective reasoning.  相似文献   
998.
We explore the feasibility of automatically identifying sentences in different MEDLINE abstracts that are related in meaning. We compared traditional vector space models with machine learning methods for detecting relatedness, and found that machine learning was superior. The Huber method, a variant of Support Vector Machines which minimizes the modified Huber loss function, achieves 73% precision when the score cutoff is set high enough to identify about one related sentence per abstract on average. We illustrate how an abstract viewed in PubMed might be modified to present the related sentences found in other abstracts by this automatic procedure.  相似文献   
999.
The University of Arkansas for Medical Sciences (UAMS) is planning interprofessional training in electronic health records (EHRs) and medical informatics. Training will be integrated throughout the curricula and will include seminars on broad concepts supplemented with online modules, didactic lectures, and hands-on experiences. Training will prepare future health professionals to use EHRs, evidence-based medicine, medical decision support, and point-of-care tools to reduce errors, improve standards of care, address Health Insurance Portability and Accountability Act requirements and accreditation standards, and promote appropriate documentation to enable data retrieval for clinical research. UAMS will ensure that graduates are ready for the rapidly evolving practice environment created by the HITECH Act.  相似文献   
1000.
Geographical research often involves searching for place names in full-text resources, such as digitized books. Place names often have variants, resulting in many different names for a single geographical place, a problem that can lead to missed results in full-text searches for place names. The problem occurs because full-text search engines merely match words in the search box with words in online documents, leaving place–name variants unsearched. This paper describes how relevant resources can be missed due to this problem and describes the different sources of place–name variation. Finally, the paper describes some solutions to the place–name variation problem in full-text searching.  相似文献   
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