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101.
This article examines the effect that postsecondary education has on earnings and the duration of time spent in the Social Security disability programs for young persons who are deaf or hard of hearing. Our hypothesis is that investments in postsecondary training increase the likelihood of employment for persons who are deaf or hard of hearing and thus reduce dependency on disability-related income support programs. A longitudinal data set based upon records from the National Technical Institute for the Deaf and Social Security administrative records is used for this analysis. We find that those who graduate, even those who graduate with vocational degrees, experience significant earnings benefits and reductions in the duration of time spent on federal disability programs when compared with those who do not graduate with a degree. This finding suggests that reductions in the duration of time spent on Social Security programs are not limited to those with the highest level of scholastic aptitude and that investments in post-secondary education can benefit a broad group of deaf and hard-of-hearing persons. In addition, the data show that individuals who attend college, but withdraw before graduation, fair no better economically than individuals who never attended college.  相似文献   
102.
Preschool children (3–4 years old) were trained to perform two actions to gain different outcomes, in the form of video clips from different cartoons, before one of these outcomes was devalued by noncontingent exposure. The effect of outcome devaluation was subsequently assessed in an extinction test by giving children the opportunity to perform both actions in the absence of any outcomes. When the two actions were trained concurrently, performance during the test was modulated by outcome value and children showed a preference for the action trained with the currently valued outcome. By contrast, when each action was trained separately on different trials, test performance was insensitive to outcome devaluation. These effects of the training schedules are interpreted in terms of dual-process theories of action control.  相似文献   
103.
我经常收到一些读者投稿,作文前面往往附着自我简介之类的资料,这些文字往往很有灵气,就是家常话也给人一种很亲切的感觉。比如,有个同学爆料她的家庭,说爸爸生意失败,一家人过得很苦,后来爸爸振作精神去跑运输,又出了车祸。妹妹不太听话,吃  相似文献   
104.
OBJECTIVE: This study examined specific aspects of child sexual abuse in relation to symptom severity among hospitalized patients diagnosed with bulimia nervosa. METHOD: Participants were 45 hospitalized bulimic women who reported a history of child sexual abuse. Structured interviews were conducted in order to obtain detailed information regarding specific features of the abusive event(s). Participants also completed instruments that measured depression and eating pathology. RESULTS: There were no significant differences in severity of depression or eating disturbance among women reporting differing abusive experiences including intrafamilial versus extrafamilial abuse, abuse with or without the use of physical force, one versus multiple incidents, early abuse versus abuse occurring after age 14, contact versus noncontact abuse, disclosed versus undisclosed, and combined physical/sexual abuse versus sexual abuse alone. CONCLUSION: The specific characteristics of child sexual abuse are not related to the level of symptomatology for hospitalized bulimic patients. This study suggests that differences in the nature of the abuse may not be as important as the fact that the abuse occurred in the first place.  相似文献   
105.
周星驰了不得,一个人就能把千千万万男女老少逗得前仰后合稀里哗啦。不过,浩瀚搞笑天地,老是靠一人撑着顶着扛着玩着也实在难为他。偏偏他又喜欢孤身作战,老没下决心培养接班人,将周氏搞笑风采有计划有方向地传播延续下去。我等看在眼里,急在心里,特地为星爷苦心搜罗11位头号接班人,请无厘头掌门人尽早留心考察这些人选,争取在明年此时师徒并肩搞笑,星光DOUBLE灿烂!  相似文献   
106.
Pigeons' keypecking was reinforced by food on baseline schedules of multiple variable interval (VI) x VI x and on contrast schedules of multiple VI x VI y. Deprivation of food was varied by maintaining subjects at 75%, 85%, and 95% (+/- 2%) of their free-feeding weights. Positive and negative behavioral contrast were observed. The size of the contrast was not systematically altered by changes in deprivation. Positive and negative contrast were both larger later in the session than they were earlier. Within-session decreases in responding were steeper for the baseline than for the contrast schedules for positive contrast. Within-session decreases were steeper for the contrast than for the baseline schedules for negative contrast. These results were predicted by the idea that different amounts of habituation to the reinforcer during the baseline and contrast schedules contribute to behavioral contrast. The results show that contrast occurs under conditions that reduce the effect of the following component. The results support the assumption that positive and negative contrast are produced by symmetrical theoretical variables.  相似文献   
107.
伸展在晶格内的离子键很强,因此从晶格中移走离子是困难的。由于这个原因,离子型化合物具有较高的熔点和沸点。存在于共价型固体或液体中的分子间的作用力没有这样强(除1~2例外),使分子聚集在一起的作用力布遍于固体中也是不强的。考虑下列的气化热:  相似文献   
108.
INTRODUCTIONRiceseedharborsadozenofplantpathogen icbacteria (Gotoetal.,1 988;Xieetal.,1 998) .Thebacterialpathogenscausearangeofricediseases,someverydestructivewhileothershavenoeffectonricecropgrowth .Inthisstudy ,wefoundalargenumberofbacteriaasso ciatedw…  相似文献   
109.
110.
砂秘辱如.诬西德尼.哈里斯漫画@西德尼.哈里斯~~  相似文献   
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