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1.
Arch Environ Contam Toxicol ; 43(3): 356-63, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12202933

RESUMO

Raccoons (n = 95) were collected from the U.S. Department of Energy's Savannah River Site (SRS) and from public hunting areas. Raccoons were collected near a stream drainage system (Steel Creek delta) and a former reactor-cooling reservoir (pond B) that received inputs of mercury-contaminated Savannah River water. Mercury concentrations were determined for hair, liver, kidney, muscle, and spleen tissues. Samples were analyzed using inductively coupled plasma mass spectroscopy (ICP-MS) and cold vapor atomic absorption spectroscopy (CVAAS). Raccoons were also collected from a natural stream floodplain system (Upper Three Runs/Tinker Creek) located upstream of Hg use and storage areas and near coal ash basins. These samples were compared to samples collected from off-site hunting areas near the SRS. Hg concentrations between internal tissues were significantly correlated. Hair did not correlate well with internal tissue and was a weak indicator of raccoon exposure to Hg. Nonetheless, raccoons are potentially good indicators of Hg contamination because tissue concentrations were higher in raccoons from areas with known Hg input than in those from reference areas, and muscle biopsies can be used as biomarkers for contaminant exposure. Muscle Hg concentrations ranged from 0-0.14 ppm from nearby hunting grounds, indicating that people hunting in designated areas near the SRS are at negligible risk for Hg consumption from raccoon meat. Several raccoons collected from the SRS had muscle Hg concentrations at or near the FDA action level for seizing commercial fish due to mercury contamination of 1.0 ppm. Though Hg action levels for wild game have not been proposed, it is clear that some SRS raccoons had Hg levels that warrant concern if these areas would be open to public hunting. Last, 64 raccoons from this study had Hg concentrations that were considered elevated by the U.S. FWS standard (> 1.1 ppm) of ecosystem health for one or two tissues (hair, liver, or kidney), and 17 had high concentrations for most or all tissues.


Assuntos
Poluentes Ambientais/farmacocinética , Mercúrio/farmacocinética , Guaxinins , Animais , Monitoramento Ambiental , Poluentes Ambientais/análise , Feminino , Rim/química , Fígado/química , Masculino , Mercúrio/análise , Músculo Esquelético/química , South Carolina , Baço/química , Distribuição Tecidual
2.
Environ Monit Assess ; 74(1): 67-84, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11893161

RESUMO

Levels of arsenic, cadmium, chromium, copper, lead, manganese, selenium, and strontium88 were examined in heart, kidney, muscle, spleen and liver of raccoons (Procyon lotor) from four areas on the Department of Energy's Savannah River Site (SRS), including near a former reactor cooling reservoir and a coal ash basin, and from public hunting areas within 15 km of the site. Mercury is mentioned briefly because it is discussed more fully in another paper. We test the hypotheses that there are no differences in metal levels between raccoons on SRS and off the SRS (off-site), and among different locations on the SRS. Although raccoons collected off-site had significantly lower levels of mercury and selenium in both the liver and kidney, there were few consistencies otherwise. There were significantly higher levels of cadmium in liver of on-site compared to off-site raccoons, and significantly higher levels of chromium and strontium88 in kidney of on-site compared to off-site raccoons. Copper and manganese were highest in the liver; cadmium, lead, mercury and selenium were highest in the liver and kidney; chromium was highest in the spleen and muscle; arsenic was highest in the heart, and strontium88 was slightly higher in the kidney than other organs. Where there were significant differences on site, chromium, manganese were highest in raccoon tissues from Steel Creek; arsenic, lead and selenium were highest in the Ash Basin; cadmium was highest at Upper Three Runs; and strontium88 was highest at Upper Three Runs and Steel Creek. The patterns were far from consistent.


Assuntos
Metais/análise , Guaxinins/metabolismo , Animais , Ecossistema , Rim/química , Fígado/química , Músculo Esquelético/química , Miocárdio/química , Especificidade de Órgãos , South Carolina , Baço/química , Distribuição Tecidual
3.
J Toxicol Environ Health A ; 60(4): 243-61, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10914690

RESUMO

The relationship between metallothionein levels and concentrations of several metals and radionuclides was examined in liver tissues of raccoons (Procyon lotor, n = 47) from the Department of Energy's Savannah River Site in South Carolina to determine the applicability of metallothioneins as an initial screening device for exposure assessment in free-living mammals and environmental monitoring. Using a fluorescent marker and a cell sorter to measure metallothionein, a significant positive correlation was found across animals between levels of metallothioneins and concentrations of selenium (Pearson's r = .30), mercury (Pearson's r = .3 1), and copper (Pearson's r = .30) in liver tissue. Arsenic, cobalt, silver, thallium, and tin were below detection limits in most or all liver samples. Other metals, including cadmium, chromium, radiocesium (137-Cs), copper, lead, manganese, strontium, and vanadium, showed only weak and nonsignificant correlations with metallothionein. Concentrations of mercury were correlated with concentrations of selenium (Pearson's r = .73), manganese (Pearson's r = .56), and strontium (Pearson's r = .57). In an a posteriori test, there was a still unexplained positive correlation between mercury (Pearson r = .56), selenium (Pearson r = .54), and radiocesium (Pearson's r = .38) concentrations and background cellular autofluorescence, and a negative correlation of strontium with the latter (Kendall tau = -.38). Background cellular autofluorescence may represent a generalized cellular stress response, or a yet unidentified biomarker. To better understand which metals contribute to the induction of metallothionein, principle component analysis (PCA) was performed. The first three principle components explained 78% of the variance, with highest loadings being from mercury and radiocesium. Metallothionein levels did not correlate well with the principal components from the metals and radiocesium, while autofluorescent background levels tended to correlate better.


Assuntos
Monitoramento Ambiental , Fígado/química , Metalotioneína/análise , Metais/análise , Guaxinins , Animais , Arsênio/análise , Peso Corporal , Radioisótopos de Césio/análise , Cobre/análise , Poluição Ambiental/análise , Citometria de Fluxo , Geografia , Fígado/enzimologia , Masculino , Manganês/análise , Mercúrio/análise , Metais Pesados/análise , Valor Preditivo dos Testes , Selênio/análise , South Carolina , Estrôncio/análise
4.
J Toxicol Environ Health A ; 58(4): 245-60, 1999 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-10591491

RESUMO

It is important to understand the perceptions of user groups regarding both the health of our estuaries and environmental problems requiring management. Recreational fishers were interviewed to determine the perceptions of one of the traditional user groups of Barnegat Bay (New Jersey), and elected officials were interviewed to determine if the people charged with making decisions about environmental issues in the bay held similar perceptions. Although relative ratings were similar, there were significant differences in perceptions of the severity of environmental problems, and for the most part, public officials thought the problems were more severe than did the fishers. Personal watercraft (often called Jet Skis) were rated as the most severe problem, followed by chemical pollution, junk, overfishing, street runoff, and boat oil. Small boats, sailboats, wind surfers, and foraging birds were not considered environmental problems by either elected officials or fishermen. The disconnect between the perceptions of the recreational fishers and those of the locally elected public officials suggests that officials may be hearing from some of the more vocal people about problems, rather than from the typical fishers. Both groups felt there were decreases in some of the resources in the bay; over 50% felt the number of fish and crabs had declined, the size of fish and crabs had declined, and the number of turtles had declined. Among recreational fishers, there were almost no differences in perceptions of the severity of environmental problems or in changes in the bay. The problems that were rated the most severe were personal watercraft and overfishing by commercial fishers. Recreational fishers ranked sailboats, wind surfers, and fishing by birds as posing no problem for the bay. Most fishers felt there had been recent major changes in Barnegat Bay, with there now being fewer and smaller fish, fewer and smaller crabs, and fewer turtles. The results suggest that the views of a wide range of coastal users should be considered when making environmental health decisions.


Assuntos
Braquiúros , Exposição Ambiental/efeitos adversos , Peixes , Política , Recreação , Adulto , Animais , Coleta de Dados , Feminino , Contaminação de Alimentos , Humanos , Masculino , New Jersey , Alimentos Marinhos , Poluição da Água
5.
J Pers Soc Psychol ; 60(4): 531-44, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2037965

RESUMO

The contact hypothesis predicts that cooperative interaction with members of a disliked group results in increased liking for those members and generalizes to more positive attitudes toward the group. The authors sought to provide evidence consistent with the hypothesis that contact affects attitude in part by eliciting a more positive portrait of the typical group member. Undergraduates participated in a 1-hr dyadic learning session (scripted cooperative learning, jigsaw cooperative learning, or individual study) with a confederate portrayed as a former mental patient. Students initially expected the confederate to display traits similar to those of a typical former mental patient. After the sessions, initially prejudiced students in the 2 cooperative conditions described the typical mental patient more positively and adopted more positive attitudes and wider latitudes of acceptance toward the group. Connections between intergroup attitudes and impression formation are discussed.


Assuntos
Atitude , Comportamento Cooperativo , Processos Grupais , Relações Interpessoais , Preconceito , Atitude Frente a Saúde , Feminino , Generalização Psicológica , Humanos , Masculino , Transtornos Mentais/psicologia
6.
Child Dev ; 61(1): 191-200, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2307039

RESUMO

Teachers convey evaluations through such "appraisal actions" as ability versus effort attributions for children's performance, spontaneous displays of warmth versus matter-of-fact acceptance, and attention versus inattention. Some appraisal actions (e.g., ability-effort) require an understanding of multiplicative relations to arrive at an "adult" interpretation. Others (e.g., attention-inattention) do not. First through sixth graders watched videotaped scenes in which teachers attributed one child's performance to ability but chided another for lack of effort even though he had given an equivalent performance, hugged one child but not another for equivalent performance, and paid attention to one child's oral report but not another's. Younger students (ages 5-9 to 7-10) rated the ability-attributed and hugged children as smarter; older students (ages 9-9 to 11-10) rated the effort-attributed and unhugged children as smarter. In contrast, no age differences were found in decoding attention versus inattention. The results suggest that younger children use a different strategy in decoding the meanings of complex appraisal actions.


Assuntos
Desenvolvimento Infantil , Percepção Social , Aptidão , Atenção , Criança , Pré-Escolar , Humanos , Controle Interno-Externo , Motivação , Reforço Social , Ensino
7.
J Pers Soc Psychol ; 56(5): 698-708, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2724065

RESUMO

Tested whether having tokens (Ts) adopt the role of judge reduces cognitive deficits; examined several hypotheses to explain these deficits. In 3 experiments, Ss were asked to remember as many as possible of opinions exchanged in a group interaction with 3 actors. Experiment 1 demonstrated that judging majority members helped gender Ts improve their memory and ruled out self-denigration as a mediator of token deficits. Experiment 2 indicated that judging others was effective regardless of whether the others were said to know about it or not, ruling out insulation from evaluative scrutiny as a viable mediator for the judge role. Experiment 3 suggested the judge role restores completely the Ts, cognitive capacities and ruled out heightened responsibility as an explanation for the improved memory of judges. This work suggests that Ts may perform better if they can restructure cognitively their social environments.


Assuntos
Escolha da Profissão , Identidade de Gênero , Identificação Psicológica , Memória , Rememoração Mental , Preconceito , Atenção , Cognição , Humanos , Autoimagem , Estereotipagem
8.
J Pers Soc Psychol ; 50(1): 106-15, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3701568

RESUMO

Pairs of subjects participated in two unstructured conversations spaced one week apart. In the second session, one subject of the pair was asked to participate either as an ingratiator or as a self-promoter. Naive target subjects clearly distinguished between presenters attempting to appear likable or competent. As verified by observer subjects, ingratiators used reactive verbal and nonverbal behaviors, whereas promoters used proactive behaviors. Preparation time did not produce differential behavioral tactics. The results are discussed in terms of the use of conversational resources to produce the attributions of likability and competence.


Assuntos
Logro , Relações Interpessoais , Autoimagem , Adulto , Feminino , Humanos , Masculino , Enquadramento Psicológico , Comportamento Verbal
9.
J Pers Soc Psychol ; 49(4): 918-26, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4057050

RESUMO

Historically, women and minority group members have been underrepresented in the professions and in better paying, high-status jobs. Even when they have been admitted to such positions, these underrepresented persons often have been the only member of their social category: a token. Previous field and laboratory research has shown that "tokens" attract disproportionate attention and are either evaluated unfairly or evaluated on the basis of their normal reactions to differential treatment by majority group members. We tested the possibilities of whether tokens might suffer more cognitive deficits than would nontokens, and whether they do so even when they are treated no differently. College students were led to believe that they were sharing their views on everyday topics with three other students (actually videotaped confederates), who were either all of the student's own sex or all of the opposite sex. In a later memory test, token participants remembered fewer of the opinions that they and the three other students had expressed than did nontokens. Observers, in contrast, remembered more of what token subjects said than what the three other students said. Theoretical and public policy implications are discussed.


Assuntos
Memória , Grupos Minoritários/psicologia , Atenção , Cognição , Feminino , Processos Grupais , Humanos , Relações Interpessoais , Masculino , Fatores Sexuais , Percepção Social
10.
J Pers Soc Psychol ; 47(6): 1231-43, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6527215

RESUMO

It is proposed that several biases in social judgment result from a failure--first noted by Francis Bacon--to consider possibilities at odds with beliefs and perceptions of the moment. Individuals who are induced to consider the opposite, therefore, should display less bias in social judgment. In two separate but conceptually parallel experiments, this reasoning was applied to two domains--biased assimilation of new evidence on social issues and biased hypothesis testing of personality impressions. Subjects were induced to consider the opposite in two ways: through explicit instructions to do so and through stimulus materials that made opposite possibilities more salient. In both experiments the induction of a consider-the-opposite strategy had greater corrective effect than more demand-laden alternative instructions to be as fair and unbiased as possible. The results are viewed as consistent with previous research on perseverance, hindsight, and logical problem solving, and are thought to suggest an effective method of retraining social judgment.


Assuntos
Julgamento , Atitude , Pena de Morte , Cognição , Extroversão Psicológica , Humanos , Introversão Psicológica , Resolução de Problemas
11.
J Pers Soc Psychol ; 46(6): 1254-66, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6737212

RESUMO

This article addresses the questions of when we can predict from an individual's attitude toward a social group to the individual's behavior toward a specific member of that group. One possibility is that individuals determine their attitudes toward a social group by assessing their reactions to an imagined group representative who embodies the defining or central group characteristics--the prototypical group member. When they encounter a specific group member whose characteristics match well those of the "attitude prototype", individuals display attitude-behavior consistency; when the match is poor, they display attitude-behavior inconsistency. This proposition was tested in two experiments, and in each the attitude-behavior relationship was greater in relation to prototypical than to unprototypical group members. In addition, knowledge of an unprototypical group member had little or no effect on attitude prototypes. Rather, the unprototypical group member was dismissed as atypical, leaving the prototype intact to influence future social behavior. The implications for attitude change, and possible applications to more abstract attitudes, are discussed.


Assuntos
Atitude , Relações Interpessoais , Personalidade , Adulto , Humanos , Masculino , Enquadramento Psicológico , Desejabilidade Social
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