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1.
Midwest Educ Res (Akron) ; 26(2): 3-27, 2014 Jun.
Article in English | MEDLINE | ID: mdl-25866457

ABSTRACT

The relationships between adolescent ethnic identity and attitudes toward school and school climate are investigated in a small, multiracial/multiethnic city in the Great Lakes region with ethnically diverse adolescents taught by primarily White teachers. The mixed methods investigation of 986 eighth through eleventh grade students during the 2010-2011 academic year suggests that the relationship between ethnic identity and attitude toward school is a complex interaction among individual characteristics of ethnicity/race, ethnic identity, gender, and ecological context. Quantitative results reveal that White female and Hispanic and African American male students exhibit strong ethnic identity that correlates positively with school attitude; however, qualitative results indicate very different paths in getting to those outcomes. Hispanic students appear to benefit from a strong ethnic identity that assists with positive relationships at school, while African American male students utilize parental cultural socialization as a protective function in school. The results emphasize the implications of positive school climates for all students.

2.
Environ Int ; 61: 127-37, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24161360

ABSTRACT

The present study investigated occurrence of environmental estrogens (EEs) in waterways managed by the Metropolitan Water Reclamation District of Greater Chicago ('District') - one of the largest and most complex water districts in the United States. The objectives of the study were: (i) to document spatial and temporal occurrence of EEs in the Chicago Area Waterways (CAWs); (ii) to determine whether water reclamation plant (WRP) effluents contribute to estrogenic pollution of the receiving streams; (iii) to determine whether the mandated water quality monitoring data could be used to predict estrogenic pollution in the receiving streams; and (iv) to determine whether snow melt, storm runoff and combined sewer overflows may also be contributors of estrogenic activity to these systems. The estrogenic potency of the waterways was assessed using a cell-based reporter gene assay. The water quality data was readily available as part of the District's regular monitoring program. Our findings indicate that EEs are commonly found in the CAWs, and that WRP effluents are one of, but not the only important contributor to estrogenic activity. Mean estrogenic activities in CAWs (11ng estradiol equivalents (EEQs/L)) are well within the values reported for other urban areas and WRP effluents. The estrogenic activity exhibited significant seasonal variation with highest values noted during the spring and summer months. When comparing the mean estrogenic activity of general use waters, secondary contact waters and WRP effluents, we found that general use waters had significantly lower estrogenic activity (ca 5ng EEQ/L) than the other two matrices (ca 15 and 17ng EEQ/L respectively). Our analyses indicate that estrogenic activity of the waterways was not reliably associated with mandated water quality parameters, and that such measurements may not be useful for predicting estrogenic activity, especially so in the complex urban systems. One of the prominent findings of this study is that EEs do not follow predictable spatial patterns - many of the upstream sites in the heavily urbanized areas had levels of estrogenic activity comparable to those found in the effluents and downstream locations. Our data suggest that surface runoff and snow melt are estrogenic (0-9ng EEQ/L), and given that their estrogenic activities are similar to those of their receiving waterways (0-7ng EEQ/L), we conclude that these non-WRP sources are important contributors to estrogenic activity of the CAWs.


Subject(s)
Ecosystem , Environmental Monitoring , Estrogens/analysis , Water Pollutants, Chemical/analysis , Chicago , Seasons , Water Purification , Water Quality
3.
Environ Int ; 61: 138-49, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24029288

ABSTRACT

Urban aquatic ecosystems are often overlooked in toxicological studies even though they serve many ecosystem functions and sustain fish populations despite large-scale habitat alterations. However, urban fish populations are likely exposed to a broad range of stressors, including environmental estrogens (EEs) that may affect anatomy, physiology and reproduction of exposed fish. Although significant progress has been made in establishing ecological consequences of EE exposure, these studies have focused largely on hydrologically simple systems that lack the complexity of urban aquatic environments. Therefore, the objective of this study was to assess the occurrence and biological effects of EEs across a large urbanized aquatic ecosystem. A multi-pronged study design was employed relying on quantitative determination of select EEs by liquid chromatography tandem mass spectrometry and repeated biological monitoring of wild-caught and caged fish for indications of endocrine disruption. Over three years, EEs were measured in aqueous samples (n=42 samples) and biological effects assessed in >1200 male fish across the 2000km(2) aquatic ecosystems of the Greater Metropolitan Area of Chicago, IL. Our study demonstrated that in addition to water reclamation plant (WRP) effluents, non-WRP sources contribute significant EE loads to the aquatic ecosystem. While resident and caged male fish responded with the induction of the egg-yolk protein vitellogenin, an indicator of EE exposure, neither resident nor caged sunfish exhibited prevalent histopathological changes to their reproductive organs (i.e., intersex) that have been reported in other studies. Vitellogenin induction was greater in spring than the fall and was not correlated with body condition factor, gonadosomatic index or hepatosomatic index. Exposure effects were not correlated with sites downstream of treated effluent discharge further affirming the complexity of sources and effects of EEs in urban aquatic ecosystems.


Subject(s)
Ecosystem , Environmental Monitoring , Estrogens/analysis , Estrogens/pharmacology , Fishes/physiology , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/pharmacology , Animals , Chicago , Endocrine Disruptors/analysis , Endocrine Disruptors/pharmacology , Estradiol/analysis , Gonads/drug effects , Liver/drug effects , Male , Reproduction/drug effects , Rivers/chemistry , Seasons , Testis/drug effects , Urban Population , Vitellogenins/blood
4.
Drug Alcohol Depend ; 117(1): 38-44, 2011 Aug 01.
Article in English | MEDLINE | ID: mdl-21296508

ABSTRACT

BACKGROUND: Sleep difficulty is a common symptom of cannabis withdrawal, but little research has objectively measured sleep or explored the effects of hypnotic medication on sleep during cannabis withdrawal. METHODS: Twenty daily cannabis users completed a within-subject crossover study. Participants alternated between periods of ad libitum cannabis use and short-term cannabis abstinence (3 days). Placebo was administered at bedtime during one abstinence period (withdrawal test) and extended-release zolpidem, a non-benzodiazepine GABA(A) receptor agonist, was administered during the other. Polysomnographic (PSG) sleep architecture measures, subjective ratings, and cognitive performance effects were assessed each day. RESULTS: During the placebo-abstinence period, participants had decreased sleep efficiency, total sleep time, percent time spent in Stage 1 and Stage 2 sleep, REM latency and subjective sleep quality, as well as increased sleep latency and time spent in REM sleep compared with when they were using cannabis. Zolpidem attenuated the effects of abstinence on sleep architecture and normalized sleep efficiency scores, but had no effect on sleep latency. Zolpidem was not associated with any significant side effects or next-day cognitive performance impairments. CONCLUSIONS: These data extend prior research that indicates abrupt abstinence from cannabis can lead to clinically significant sleep disruption in daily users. The findings also indicate that sleep disruption associated with cannabis withdrawal can be attenuated by zolpidem, suggesting that hypnotic medications might be useful adjunct pharmacotherapies in the treatment of cannabis use disorders.


Subject(s)
Cannabinoids/pharmacology , Hypnotics and Sedatives/therapeutic use , Pyridines/therapeutic use , Sleep Initiation and Maintenance Disorders/drug therapy , Sleep/drug effects , Substance Withdrawal Syndrome/pathology , Adult , Cannabis/metabolism , Control Groups , Cross-Over Studies , Delayed-Action Preparations , Double-Blind Method , Female , Humans , Male , Middle Aged , Placebos , Polysomnography , Sleep Initiation and Maintenance Disorders/complications , Sleep, REM/drug effects , Substance Withdrawal Syndrome/complications , Substance Withdrawal Syndrome/metabolism , Young Adult , Zolpidem
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