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Journal of Youth and Adolescence - Strong school engagement is crucial for school success among adolescents and particularly important for reducing recidivism. Yet, little is known about school...  相似文献   
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The contribution that parental educational expectations for youth and youth’s perceptions of academic competence can have on youth’s own educational expectations across early to late adolescence is not well-understood. In a sample of Mexican-origin families, the current study examined longitudinal (from early to late adolescence) associations among mothers, fathers, and youth’s educational expectations, how youth’s educational expectations were associated with perceived academic competence, and the potential mediating role of youth’s perceived academic competence. Data from two-parent families which included one focal child (7th grade: N=?469; youth: Mage?=?12.31, 50% female) at three waves (7th, 9th, and 11th grade) were utilized. Structural equation modeling and multi-group analysis were implemented to assess the study’s goals. Results revealed significant associations among parents’ 7th grade educational expectations and youth’s 9th and 11th grade educational expectations. The findings also revealed three significant associations among youth’s perceived academic competence and educational expectations between 7th and 11th grade. Specifically, youth’s 7th grade perceived academic competence predicted youth’s 9th grade educational expectations, youth’s 7th grade educational expectations predicted youth’s 9th grade perceived academic competence, and youth’s 9th grade perceived academic competence predicted youth’s 11th grade educational expectations. Multigroup analysis did not reveal gender differences for the associations tested. The findings highlight the long-term significance of parents’ educational expectations on youth’s educational expectations and underscore youth’s academic competence, an individual level factor, as critical to consider for understanding educational expectations across adolescence for Mexican-origin youth.

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A 40-year-old man was admitted to the emergency department after a suicide attempt. The patient was found at home unconscious, with an open bottle of antifreeze near him. The patient was in a coma on admission, but neurological examination excluded intracranial changes. Results of initial urine and serum toxicological screening tests were negative. Laboratory values indicated metabolic acidosis, leukocytosis, urinalysis revealed hematuria and unrecognized crystals. Osmolality and osmol gap were not determined on patient admission. Treatment with ethanol as an antidote and hemodialysis were started because of metabolic acidosis, anamnestic data and clinical status of the patient, and subsequently led to improvement of his condition. Further toxicological analyses of glycolic and oxalic acids in serum and urine samples were performed by ion-chromatography (IC) method and showed high values in spot urine and serum ultrafiltrate at admission, but during therapy the values progressively decreased. Treatment of poisoned patient for 3 weeks resulted in complete recovery.  相似文献   
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The preservation of teeth that have been exposed to a heat source is a key factor in order to keep their value as evidence. This research paper presents some methods under development for the analysis of dental evidence after exposure to high temperatures; it also establishes age related alterations of young and aged teeth which have been exposed to direct heat. A total of thirty permanent healthy teeth (young=15 and old=15) were submitted to direct heat (n=14) and to a controlled raise of temperature (n=16); they were embedded in polymethylmetacrilate. For the macroscopic study, blocks were cut in half, polished and their surfaces were digitalized. Subsequently, blocks were put in slides, worn away and observed through a photomicroscope. The study of the colorimetric pattern was done by Corel Photo Paint 12.0 and Image J. software. All teeth submitted to the gradual raise of temperature presented a degree of structural damage lower than those exposed to direct heat. The internal surface of young teeth exposed to direct heat showed lines of fracture oblique to the long axis of the tooth; in contrast, a reticular pattern was observed on aged teeth. All teeth exposed to direct heat showed some matte-black coloration areas, while those submitted to a gradual increment of temperature showed a greyish colour in the enamel and a chalky-white in the cementum. By using both thermal treatments in young teeth, the amelodentinal junction was lost, thus preserving the integrity of each tissue. In aged teeth, the separation of this junction was produced because of the breakdown of the dentine. Microscopically, in teeth exposed to direct heat, it was neither possible to differentiate the dentin from the cementum, nor to distinguish the incremental lines of the latter; while in those submitted to a controlled increment of temperature, the corresponding morphology in the tissues was observed. A significant statistical difference was obtained for black colour among young and aged teeth exposed to direct heat, as well as among the means of all colours obtained from the teeth exposed to both treatments. The structural changes observed allow locating a tooth in the studied age groups. Our results show the viability of the applied method for the processing of samples, allowing their preservation as evidence during an indefinite time.  相似文献   
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