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993.
Among the variables affecting comprehension of linguistic stimuli by aphasic subjects are syntactic complexity and processing time. Comprehension performance of 15 aphasic adults was studied while altering the rate of speech presentation and varying the pause time between the major phrases within sentences of increasing grammatical complexity.Simple Active Affirmative Declarative Sentences, Negative, and Passive sentences were presented (1) at the rate of 150 words per minute (wpm) with 1-sec interphrase pause time (IPT); (2) 150 wpm with no pauses; (3) 120 wpm with 1-sec IPT; (4) 120 wpm with no pauses added.Performance was seen to vary with increasing syntactical complexity and as a function of processing time. Greater comprehension was seen with active affirmative than negative; greater with passive affirmative than with active negative. Clinical implications are discussed. Subjects demonstrated greater comprehension when sentences were presented at slower than normal rate; addition of interphrase pause time intervals aided comprehension. Combining slower rate of presentation and IPT intervals provided greatest increase in auditory processing time and showed concomitant increase in comprehension performance.  相似文献   
994.
This study investigated the culture of driving distractions among commercial bus drivers in Ile-Ife, Southwestern Nigeria. The aim was to identify the most prominent non-driving activity (N-DA) causing distraction to drivers. 16 independent research assistants were engaged in naturalistic recording of 128 commercial bus drivers in the study area. Among the variables selected for observation, passenger scouting (93%), fare collection (89.8%) and money counting (75%) were found to be the frequent N-DAs in their order of importance. These variables (passenger scouting, fare collection and money counting), however, have correlations with drivers having no conductor on-board. More so, relationships existed between certain N-DAs (call making, passenger scouting, fare collection sight-seeing and money counting) and loss of concentration by drivers on one hand; and between loss of concentration and the forms the loss of concentration took. It can be concluded from the findings that driving was disrupted and uncoordinated when combined with non-driving activities.  相似文献   
995.
古代山东地区的蚕桑丝织业一直在全国居于中心地位,无论是生产规模、普及程度以及绢帛质量都居全国之首,其基础就在于山东地区有先进、发达的蚕桑丝织技术。本文以《齐民要术》的有关记载,结合其它资料,从种桑、养蚕、初加工、颜料诸方面了解一下古代山东的蚕桑和生产技术。  相似文献   
996.
Lyman A. Page 《Zygon》2007,42(3):767-778
Progress in technology has allowed dynamic research on the development of the human brain that has revolutionized concepts. Particularly, the notions of plasticity, neuronal selection, and the effects of afferent stimuli have entered into thinking about brain development. Here I focus on development from the age of four years to early adulthood, during which a 30 percent reduction in some brain synapses occurs that is out of proportion to changes in neuronal numbers. This corresponds temporally with changes in normal child behavior from the loose‐associative, almost schizoid, thinking and art of the four‐year‐old to the more trained, or disciplined, or acculturated—and restrained—personality of the young adult. I propose that the synaptic changes can best be thought of as a winnowing process likely subject to environmental influences. Acquisition of language and the ability to link linguistic cognition to the plastic development of the brain provide a potentially powerful means of explaining the evolutionally explosive development of human cognition and culture. Schizophrenia, a disease that can be envisioned as representing a derangement of synaptic maturation, may provide an entry into the search for genes controlling the processes mediating the unprecedented development of Homo sapiens over the past 40,000 to 70,000 years. The recently completed mapping of the genome of the chimpanzee provides a new frame of reference that may speed the search.  相似文献   
997.
Recent experience with attempts to test relatively simple patterns such as three-tone sequences in a traditional dichotic-listening paradigm indicates that when such sequences are used for both target and contralateral interference, performance tends to be low in both ears and not useful for measuring or comparing ear advantages in various target conditions. It is reported that tests with a variety of sounds presented contralaterally to three-element patterns show that several such sounds can (1) allow performance in at least one ear to remain above floor values, (2) result in performance in at least one ear that is below ceiling, and (3) reveal ear advantages that are similar in direction and magnitude to those seen with the traditional dichotic paradigm.  相似文献   
998.
Time to collision (TTC) has been a key vehicle safety metric for decades. With the increasing prevalence of advanced driver assistance systems and vehicle automation, TTC and many related metrics are being applied to the analysis of more complicated scenarios, as well as being integrated into automation algorithms. While the TTC metric was originally conceived to be inclusive of generic two-dimensional situations, its applications has been mostly limited to one-dimensional scenarios. This paper derives general equations and algorithms using two-dimensional information. Additionally, methods from computational geometry, a field that didn’t exist when TTC was first used, are employed for the general case of computing TTC between bounding boxes. Parametric equations for lines play a prominent role and offer an elegant way to express the geometry of the scenarios described in this paper. Throughout, the approach is not to derive specific algebraic conditions as in previous efforts. Rather, the focus in on developing general algorithms for computation. The techniques presented are not necessary for traditional car following scenarios; but offer options for more complex situations that trade off analytic solutions for computational flexibility.  相似文献   
999.
In this study the eco-cultural model of parenting (Keller, H. (2007). Cultures of infancy. Mahwah, NJ: Erlbaum) was applied to the study of joint attention behavior of children from families with different socio-economic status (SES). It was hypothesized that infants’ early communication styles would differ with SES reflecting more independent or interdependent interactions with their caregivers. It was also hypothesized that infants would use the same types of behaviors whether they have declarative or imperative communication goals. The Early Social Communication Scales (ESCS, Mundy et al., 2003) was administered to 103 typically developing infants of 12 months (approximately half of them siblings of children with autism). A factor analysis, yielding four behavioral factors, namely pointing, eye contact, actions and following points, confirmed the hypothesis that infants use behaviors consistently across situations independent of their communicative intent. MANOVAs (comprising parental education and income) revealed that higher SES infants showed actions more frequently in the ESCS whereas lower SES infants followed experimenter's points more frequently. The results are discussed in the context of presumably differing socialization goals for infants and the divergent contribution of parental education and income that seem to have additive contribution to some factors (actions, following points) but divergent contributions to others (pointing, eye contact).  相似文献   
1000.
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