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41.
Previous research has found that children engage in Level 2 visual perspective-taking, that is, the understanding that others may see things in a different way, between 4 and 5 years of age (e.g., J. H. Flavell, B. A. Everett, K. Croft, & E. R. Flavell, 1981). This ability was reexamined in 36-month-olds using color filters. In Experiment 1 (N = 24), children had to recognize how an object looked to an adult when she saw it through a color filter. In Experiment 2 (N = 24), a novel production test was applied. Results of both studies show that 36-month-olds know how an object looks to another person. The discussion focuses on the psychological requirements of visual perspective-taking and its relation to other "theory of mind" abilities, such as the distinction between appearance and reality and understanding false belief.  相似文献   
42.
OBJECTIVE: This study examines the relationship between parental self-confidence, warmth, and involvement, and corporal punishment in families of children with attention deficit/hyperactivity disorder (ADHD). METHOD: The diagnosis of ADHD was established through clinical interviews with the parents, children, and teachers, according the criteria in DSM-IV-TR. This diagnosis was also established by having the parents complete the Conners' Parent Rating Scale, and the teachers complete the Conners' Teacher Rating Scale. Two groups of Iranian parents, one group with children who have ADHD (N=130) and a control group (N=120), completed questionnaires measuring parental self-confidence and parenting styles. RESULTS: Parents of children with ADHD were found to have lower self-confidence and less warmth and involvement with their children, and used corporal punishment significantly more than the parents of control children. CONCLUSIONS: The study provides strong evidence that children with ADHD are at considerable risk of abuse by their parents. Rather than focusing only on the child's ADHD, treatment may also need to address the parents' functioning.  相似文献   
43.
To what extent do children with autism (AD) versus typically developing children (TD) rely on attentional and intentional cues to learn words? Four experiments compared 17 AD children (M age=5.08 years) with 17 language- and 17 mental-age-matched TD children (M ages=2.57 and 3.12 years, respectively) on nonverbal enactment and word-learning tasks. Results revealed variability in all groups, but particularly within the AD group. Performance on intention tasks was the most powerful predictor of vocabulary in the AD group but not in the TD groups. These findings suggest that word learning cannot be explained exclusively by either attentional or intentional processes, and they provide evidence of a special role for intentional understanding in the vocabulary development of AD children.  相似文献   
44.
Children with mathematics learning disabilities in Belgium   总被引:6,自引:0,他引:6  
In Belgium, between 3% and 8% of the children in elementary schools have mathematics learning disabilities (MLD). Many of these children have less developed linguistic, procedural, and mental representation skills. Moreover, a majority of the children have been found to show inaccurate prediction and evaluation skills in Grade 3. MLD often become obvious in elementary school. Whereas some children are retained, others are referred to special education. During the last 10 years, the number of children in special education and the number of children with learning disabilities who are following a special guidance program in general education (inclusive education) have increased. Children in Belgium with MLD can get therapy for about 2 years. Nevertheless, many problems continue unresolved even in high school and adulthood.  相似文献   
45.
The authors examined second grade reading accuracy and fluency and their associations via letter knowledge to phonological and language predictors assessed at 3.5, 4.5, and 5.5 years in children in the Jyv?skyl? Longitudinal Study of Dyslexia. Structural equation modeling showed that a developmentally highly stable factor (early phonological and language processing [EPLP]) behind key dyslexia predictors (i.e., phonological awareness, short-term memory, rapid naming, vocabulary, and pseudoword repetition) could already be identified at 3.5 years. EPLP was significantly associated with reading and spelling accuracy and by age with letter knowledge. However, EPLP had only a minor link with reading fluency, which was additionally explained by early letter knowledge. The results show that reading accuracy is well predicted by early phonological and language skills. Variation in fluent reading skills is not well explained by early skills, suggesting factors other than phonological core skills. Future research is suggested to explore the factors behind the development of fast and accurate decoding skills.  相似文献   
46.
In this paper,we investigate the effect and the possible mechanism of high glucose levels on the calcification of human aortic smooth muscle cells (HASMCs).HASMCs were divided into four groups: normal glucose group (NG),osmolality control group (OC),high glucose group (HG,HASMCs culture medium containing 30 mmol/L glucose),and high glucose plus recombinant human Noggin protein (bone morphogenetic protein-2 (BMP-2) antagonist) group (HN).The mRNA levels and the protein expressions of BMP-2 and core binding factor alpha-1 (Cbfα-1) were measured by real-time quantitative polymerase chain reaction (PCR) and Western blot.After induced by 10 mmol/L β-glycerol phosphoric acid,cells were harvested for assessments of alkaline phosphatase (ALP) activities at Days 1,2,and 3,and intracellular calcium contents at Days 7 and 14,respectively.High glucose levels increased the mRNA levels and the protein expressions of BMP-2 and Cbfα-1 (P0.05).The expression of Cbfα-1 was partially blocked by Noggin protein (P0.05),while BMP-2 was not (P0.05).After being induced by β-glycerol phosphoric acid,high glucose levels increased the ALP activity [(48.63±1.03) vs.(41.42±2.28) U/mg protein,Day 3;P0.05] and the intracellular calcium content [(2.76±0.09) vs.(1.75±0.07) μmol/mg protein,Day 14;P0.05] in a time-dependent manner when compared with the NG group,while the ALP activity could not be blocked by Noggin protein [(48.63±1.03) vs.(47.37±0.97) U/mg protein,Day 3;P0.05].These results show that high glucose levels can evoke the calcification of HASMCs by inducing osteoblastic trans-differentiation and intracellular calcium deposition via the BMP-2/Cbfα-1 pathway,which can be partially blocked by Noggin protein.  相似文献   
47.
The aim of this study was to examine the effects of muscle-tendon length on joint moment and power during maximal sprint starts. Nine male sprinters performed maximal sprint starts from the blocks that were adjusted either to 40 degrees or 65 degrees to the horizontal. Ground reaction forces were recorded at 833 Hz using a force platform and kinematic data were recorded at 200 Hz with a film camera. Joint moments and powers were analysed using kinematic and kinetic data. Muscle - tendon lengths of the medial gastrocnemius, soleus, vastus medialis, rectus femoris and biceps femoris were calculated from the set position to the end of the first single leg contact. The results indicated that block velocity (the horizontal velocity of centre of mass at the end of the block phase) was greater (P < 0.01) in the 40 degrees than in the 65 degrees block angle condition (3.39 +/- 0.23 vs. 3.30 +/- 0.21 m . s(-1)). Similarly, the initial lengths of the gastrocnemius and soleus of the front leg in the block at the beginning of force production until half way through the block phase were longer (P < 0.001) in the 40 degrees than in the 65 degrees block angle condition. The initial length and the length in the middle of the block phase were also longer in the 40 degrees than in the 65 degrees block angle condition both for both the gastrocnemius (P < 0.01) and soleus (P < 0.01-0.05) of the rear leg. In contrast, the initial lengths of the rectus femoris and vastus medialis of the front leg were longer (P < 0.05) in the 65 degrees than in the 40 degrees block angle condition. All differences gradually disappeared during the later block phase. The peak ankle joint moment (P < 0.01) and power (P < 0.05) during the block phase were greater in the 40 degrees than in the 65 degrees block angle condition for the rear leg. The peak ankle joint moment during the block phase was greater (P < 0.05) in the 40 degrees block angle for the front leg, whereas the peak knee joint moment of the rear leg was greater (P < 0.01) in the 65 degrees block angle condition. The results suggest that the longer initial muscle-tendon lengths of the gastrocnemius and soleus in the block phase at the beginning of force production contribute to the greater peak ankle joint moment and power and consequently the greater block velocity during the sprint start.  相似文献   
48.
加强綜合技術教育,以提高學校中社會主義敎育的作用,這是所有教師們的共同任務。其中,生物學教師應該以農業經濟的科學基礎知識来武裝學生,教給學生以其力能勝任的有關農業勞動方面的實踐技能。在生物學的教學過程中,來完成綜合技術敎育這一任務,應該舆對學生進行的理論教育密切聯繫起來,因為如果學生沒有相當的科學理論修養,不懂得自然界的客觀規律,就不可能掌握社會主義農業生產的基本原則。在生物課教學中學生所獲得的理論教育,就是教師要以明白易懂的方式把米丘林和巴甫洛夫所發現的,關於生物界的生活和發展法則的知識傳授給他們。  相似文献   
49.
比较一下一个发达国家(罗马尼亚)与一个发展中国家(尼加拉瓜)对天灾的社会反应可以看出一些明显差别,使人感到后者容易遭受天灾袭击。发展中国家的人民非常贫困,促使他们有甘冒风险的倾向,容易听天由命,因此他们继续居住在危险地区。  相似文献   
50.
Ovarian cancer is the leading cause of death from gynecological malignancies in women. The primary challenge is the detection of the cancer at an early stage, since this drastically increases the survival rate. In this study we investigated the dielectrophoretic responses of progressive stages of mouse ovarian surface epithelial (MOSE) cells, as well as mouse fibroblast and macrophage cell lines, utilizing contactless dielectrophoresis (cDEP). cDEP is a relatively new cell manipulation technique that has addressed some of the challenges of conventional dielectrophoretic methods. To evaluate our microfluidic device performance, we computationally studied the effects of altering various geometrical parameters, such as the size and arrangement of insulating structures, on dielectrophoretic and drag forces. We found that the trapping voltage of MOSE cells increases as the cells progress from a non-tumorigenic, benign cell to a tumorigenic, malignant phenotype. Additionally, all MOSE cells display unique behavior compared to fibroblasts and macrophages, representing normal and inflammatory cells found in the peritoneal fluid. Based on these findings, we predict that cDEP can be utilized for isolation of ovarian cancer cells from peritoneal fluid as an early cancer detection tool.  相似文献   
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