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1.
Eur J Clin Nutr ; 70(9): 1028-33, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27222153

RESUMO

BACKGROUND/OBJECTIVES: To investigate the relationship of reporting accuracy in 24-h dietary recalls to child-respondent characteristics-cognitive ability, social desirability, body mass index (BMI) percentile and socioeconomic status (SES). SUBJECTS/METHODS: Fourth-grade children (mean age 10.1 years) were observed eating two school meals and interviewed about dietary intake for 24 h that included those meals. (Eight multiple-pass interview protocols operationalized the conditions of an experiment that crossed two retention intervals-short and long-with four prompts (ways of eliciting reports in the first pass)). Academic achievement-test scores indexed cognitive ability; social desirability was assessed by questionnaire; height and weight were measured to calculate BMI; nutrition-assistance program eligibility information was obtained to index SES. Reported intake was compared to observed intake to calculate measures of reporting accuracy for school meals at the food-item (omission rate; intrusion rate) and energy (correspondence rate; inflation ratio) levels. Complete data were available for 425 of 480 validation-study participants. RESULTS: Controlling for manipulated variables and other measured respondent characteristics, for one or more of the outcome variables, reporting accuracy increased with cognitive ability (omission rate, intrusion rate, correspondence rate, P<0.001), decreased with social desirability (correspondence rate, P<0.0004), decreased with BMI percentile (correspondence rate, P=0.001) and was better by higher- than by lower-SES children (intrusion rate, P=0.001). Some of these effects were moderated by interactions with retention interval and sex. CONCLUSIONS: Children's dietary-reporting accuracy is systematically related to such respondent characteristics as cognitive ability, social desirability, BMI percentile and SES.


Assuntos
Índice de Massa Corporal , Cognição , Inquéritos sobre Dietas/métodos , Dieta , Autorrelato/normas , Classe Social , Desejabilidade Social , Criança , Registros de Dieta , Ingestão de Alimentos , Comportamento Alimentar , Feminino , Humanos , Masculino , Refeições , Rememoração Mental , Reprodutibilidade dos Testes , Instituições Acadêmicas , Estudantes
2.
J Phys Condens Matter ; 25(1): 014007, 2013 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-23221164

RESUMO

Temperature-dependent photoemission spectroscopy in Li(0.9)Mo(6)O(17) contributes to evidence for one-dimensional (1D) physics that is unusually robust. Three generic characteristics of the Luttinger liquid are observed: power law behavior of the k-integrated spectral function down to temperatures just above the superconducting transition, k-resolved lineshapes that show holon and spinon features, and quantum critical (QC) scaling in the lineshapes. Departures of the lineshapes and the scaling from expectations in the Tomonaga-Luttinger model can be partially described by a phenomenological momentum broadening that is presented and discussed. The possibility that some form of 1D physics obtains even down to the superconducting transition temperature is assessed.


Assuntos
Lítio/química , Modelos Químicos , Modelos Moleculares , Espectroscopia Fotoeletrônica/métodos , Reologia/métodos , Soluções/química , Simulação por Computador , Condutividade Térmica
3.
Ecotoxicol Environ Saf ; 55(2): 143-51, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12742360

RESUMO

The objective of this study was to evaluate the chronic lethal and sublethal aquatic toxicity effects associated with the phytoremediation of water contaminated with 2,4,6-trinitrotoluene (TNT) by the wetland plant species Myriophyllum aquaticum (parrot feather). Rotifers (Brachionus calyciflorus) feeding on an algal species (Nannochloropsis spp.) were used as the aquatic test organisms. Continuous flow laboratory microcosms were used to quantify effects on rotifer populations from TNT and the primary degradation product aminodinitrotoluene (ADNT) during and after phytoremediation. Rotifer demographic parameters from life tables, including survivorship, fecundity, reproductive values, net reproductive rate, generation time, intrinsic growth rate, and life expectancy, were used as measures of treatment effects. High-performance liquid chromatography analyses were performed to determine nitroaromatic concentrations. Results from this study have revealed significant differences in rotifer demographic parameters between microcosms with elevated initial TNT concentrations. Significant differences in demographic parameters also existed between the microcosms that did and did not receive phytoremediation treatment and the control microcosms. Study results have indicated that TNT phytoremediation via artificial wetlands not only may clean up hazardous waste at munitions sites but also may encourage the growth of aquatic populations such as rotifers.


Assuntos
Poluentes Ambientais/toxicidade , Rotíferos/fisiologia , Trinitrotolueno/toxicidade , Algoritmos , Animais , Biodegradação Ambiental , Cromatografia Líquida de Alta Pressão , Ambiente Controlado , Poluentes Ambientais/análise , Eucariotos/efeitos dos fármacos , Humanos , Tábuas de Vida , População , Reprodução/efeitos dos fármacos , Rotíferos/genética , Análise de Sobrevida , Trinitrotolueno/análise
5.
Arch Environ Contam Toxicol ; 34(3): 259-64, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9504973

RESUMO

The nematode Caenorhabditis elegans was used in 72-h toxicity tests to evaluate the influence of ozonation on the toxicity of three synthetic azo dye wastewaters (two reactive dyes and one acid-based dye). The two reactive dye wastewaters contained high concentrations of NaCl (89-112 g/L) in addition to potentially toxic dye components. To determine the contribution of NaCl to toxicity, simulated dye wastewater samples with and without NaCl were tested. Samples were collected at various times during ozonation (t = 0, 8, 32, 64 min); nematodes were exposed to the samples for 72 h. The influence of ozonation on toxicity varied between dye wastewater types. For the acid-based dye wastewater, toxicity increased as duration of ozonation increased. For the reactive dyes without NaCl, toxicity did not appear to be influenced by ozonation. For the reactive dyes with NaCl, mortality was 100% with or without ozonation. Range-finding experiments with NaCl in water and NaCl in dye wastewaters suggested an additive toxic interaction between NaCl and the dyes in wastewater to the nematodes. The duration of ozonation for acid-based dyes and the relatively high NaCl concentrations for the reactive dyes appear to influence effluent toxicity in the ozonated dye wastewaters.


Assuntos
Caenorhabditis elegans/fisiologia , Corantes/toxicidade , Ozônio/química , Poluentes Químicos da Água/toxicidade , Animais , Poluentes Químicos da Água/análise
6.
Arch Environ Contam Toxicol ; 33(3): 252-60, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9353202

RESUMO

This investigative study assesses the ease and usefulness of the nematode Caenorhabditis elegans for identifying contributors to effluent toxicity within an industrial and municipal wastewater treatment plant (WWTP) system. Several different types of industries, including fiberglass manufacturing, paper packaging, and yarn dyeing, discharge effluent into the municipal wastewater treatment plant, which in turn discharges into a local creek. A major objective of this study was to identify primary sources of toxicity throughout the system with a nematode toxicity test. Twenty-four-hour composite water samples were taken periodically over a ten-month period at five strategic points within the system: (1) at the point of discharge at each of the three industries, (2) at the combined industrial influent of the wastewater treatment plant, (3) at the effluent of the WWTP, (4) upstream of the WWTP discharge, and (5) downstream of the WWTP discharge. Samples were analyzed for basic water chemistry, and each sample was tested for whole effluent toxicity using a 72-h nematode test with mortality as the end point. Results suggest that interactions between the wastewaters of certain industries may increase the overall nematode toxicity in the wastewater treatment facility's composite influent and effluent. Nematode mortality trends indicate relatively high toxicity levels in wastewater entering the WWTP from contributing industries. High WWTP influent toxicity may potentially be due to varying flow rate ratios of industrial discharges, release of varying toxic constituents in wastewaters, and toxic interactions between chemical constituents of industrial wastewaters. The evaluation of toxicity within the treatment system may pinpoint locations where pollution prevention strategies may be implemented to reduce overall toxicity at the point of discharge.


Assuntos
Caenorhabditis elegans , Resíduos Industriais , Testes de Toxicidade , Eliminação de Resíduos Líquidos , Animais , Georgia , Saúde da População Urbana
8.
Br Poult Sci ; 38(1): 48-54, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9088612

RESUMO

1. This paper describes how birds move between horizontal perches at different heights with different angles separating them, using the time to complete the task and the number of birds failing to indicate ability. 2. For the first experiment, 4 groups of 15 birds (ISA Brown) were subjected to each of the experimental treatments (using three perches with angles of 0 degree (horizontal control), 30 degrees, 45 degrees or 60 degrees between them). The birds were required to move upward between the perches for each treatment and then to move downward between the perches, as a second part of the experiment. 3. Birds moving up between the perches took significantly longer at 60 degrees than at any other angle. No birds failed to complete the task. 4. For birds moving downward between the perches, the median time to complete the task increased significantly with angle. Furthermore, the number of birds failing to complete the task increased with angle. 5. A second experiment was conducted to test whether the vertical or horizontal component of distance affected birds' ability to negotiate perches separated by different angles. 6. For the second experiment 4 groups of 10 Lohmann Brown laying hens were subjected to each of the following treatments: two horizontal perches separated by 30 degrees or 60 degrees and either directly, horizontally or vertically separated by a set distance of 50 cm. Birds were required to move both up and down between perches. 7. Birds negotiated horizontally-separated perches more successfully at 30 degrees than at 60 degrees. However, when the vertical distance between the perches was 50 cm there was no significant difference in the ability of birds to move downward at 30 degrees or 60 degrees. For birds moving upward, 60 degrees was easier to negotiate than 30 degrees. 8. The vertical and horizontal separations, as well as the different angles affected the ability of birds to move between perches. There was a general decreasing trend in ability with increasing vertical separation between perches. 9. The findings are important in terms of arrangements of perches to improve bird welfare. To minimise the risk of injury, the angle between perches at different heights should be no more than 45 degrees, and the horizontal and vertical distances between these perches minimised, to allow the birds to be able to move downwards more easily.


Assuntos
Galinhas , Abrigo para Animais , Locomoção , Bem-Estar do Animal , Animais , Arquitetura de Instituições de Saúde , Feminino , Matemática , Modelos Biológicos , Oviposição , Estatísticas não Paramétricas , Reino Unido
9.
Anim Behav ; 54(6): 1491-1508, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9794774

RESUMO

This study provided basic information about spatial memory in the domestic pig, Sus scrofa and examined how susceptible it is to disruption by environmental stimuli. Eight male pigs were tested individually in a foraging arena. Each day, they entered the arena to search for food randomly located in one of 10 enclosed areas (search trial). After finding and eating the food, they were removed from the arena for a retention interval, and then allowed back in to relocate the food in the same area as previously (relocation trial). Once pigs had achieved a criterion level of performance in relocation trials, 'disturbances' (e.g. isolation, novel food source, novel spatial environment) were presented during the retention interval. Disturbance days were separated by control days on which no disturbance was presented. During search trials, pigs did not use food-related cues to locate food, but appeared to use memory to search systematically and avoid revisits to empty areas. During relocation trials, they found food using fewer area visits than expected by chance, indicating that they could remember the location of food across both 10-min and 2-h retention intervals. Disturbances administered during 10-min retention intervals resulted in more relocation errors than on corresponding control days, indicating that spatial memory in pigs is susceptible to interference by relatively mild environmental stimuli, in contrast to that in rats, Rattus norvegicus and pigeons, Columba livia which appears to be highly resistant to retroactive interference even when potent stimuli are used. Analysis of error locations suggested that disturbances probably acted to increase the general area in which the pig remembered the food to be located, and so reduced accuracy of memory without eradicating it. There was no evidence that errors made during relocation trials represented sampling of areas not visited during the preceding search trial.Copyright 1997 The Association for the Study of Animal Behaviour

10.
J Exp Child Psychol ; 62(3): 378-400, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8691119

RESUMO

The cues that reactivate forgotten memories of young infants are highly specific. At the time of initial reminding, if either the cue or context differs from that originally present during encoding, then the memory is not recovered. In three experiments, we asked whether this specificity decreases over repeated reactivations. Three-month-old infants, trained in the mobile conjugate reinforcement paradigm with a particular cue in a particular context, received multiple reactivation treatments after their training memory was forgotten; either the cue or the context was changed during the final reminder. For a given age of the memory, context specificity was eliminated after fewer retrievals than cue specificity, and the number of retrievals required to eliminate specificity interacted with the age of the memory. These results confirm that different memory attributes become inaccessible at different rates and that repeatedly retrieved and older memories are likely to be less detailed. This transformation may underlie reconstructive memory in linguistic individuals.


Assuntos
Memória , Estimulação Luminosa , Desenvolvimento Infantil , Feminino , Humanos , Lactente , Masculino
12.
J Nutr ; 120 Suppl 11(Suppl 11): 1440-5, 1990 11.
Artigo em Inglês | MEDLINE | ID: mdl-2243284

RESUMO

Planning a multipurpose survey in which nutritional status is assessed requires a series of scientific and practical decisions that are constrained by available resources of money and time and by the limits to what can be expected from the respondents. This paper describes the planning process for a multipurpose survey using our experience with the third National Health and Nutrition Examination Survey (NHANES III) as an example. Ideally, the goals and objectives are well defined at the outset, and these guide the development of the survey content and statistical design. Because the needs for information are so great, criteria need to be developed for evaluating which topics will be included in the survey and what tests will be used. In planning the NHANES III, the evaluation criteria used were the scientific merit of the topic, its public health importance, its practical utility to the government, and the feasibility of implementing it within the survey's mode of operation. After the topics to be covered in a survey have been selected, questionnaires and examination protocols are developed, pilot tested, and revised prior to implementing the survey. Procedures are established for providing for informed consent and assuring the confidentiality of findings.


Assuntos
Inquéritos Nutricionais , Estado Nutricional , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Protocolos Clínicos , Confidencialidade , Humanos , Lactente , Consentimento Livre e Esclarecido , Estudos Longitudinais , Pessoa de Meia-Idade , Projetos de Pesquisa , Inquéritos e Questionários , Estados Unidos
13.
Neuron ; 4(4): 603-14, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2108708

RESUMO

We have demonstrated that immediate early genes can be differentially activated within the central nervous system. We examined the effects of tetanic stimulation in the hippocampus and of noxious sensory stimulation of the spinal cord on the expression of eight immediate early genes. Induction of long-term potentiation (LTP) in the dentate gyrus resulted in an increase in mRNA and protein for NGFI-A (also termed Zif/268, Egr-1, or Krox 24), and less consistently for jun-B mRNA. No increase was seen for c-fos, NGFI-B, c-jun, jun-D, SRF, or PC4 mRNAs. Blockade of the NMDA receptor prevented the induction of both LTP and NGFI-A mRNA in the dentate gyrus. However, commissural stimulation, which prevented the induction of LTP, resulted in bilateral activation of all the genes examined, including NGFI-A. No change was seen in animals trained in a water maze. These results suggest that no simple relationship exists between LTP, spatial learning, and immediate early gene induction. Stimulation of sensory fibers resulted in an increase in mRNA for NGFI-A, c-fos, SRF, NGFI-B, and c-jun in spinal cord neurons. Blockade of the NMDA receptor had no effect on immediate early gene induction in the spinal cord.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Hipocampo/fisiologia , Proteínas do Tecido Nervoso/genética , Medula Espinal/fisiologia , Fatores de Transcrição/fisiologia , Animais , Sequência de Bases , Estimulação Elétrica , Aprendizagem/fisiologia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Sondas de Oligonucleotídeos , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-fos , Proteínas Proto-Oncogênicas c-jun , RNA Mensageiro/genética , Ratos , Ativação Transcricional
15.
AJR Am J Roentgenol ; 135(6): 1161-5, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6779520

RESUMO

With the advent of high resolution real-time sonographic scanning machines, fetal gender can be determined in most pregnancies of more than 25 weeks. In 72 of 112 consecutive pregnancies, fetal genitalia were well visualized and there were no errors in prediction of fetal gender. In the 40 failures, the fetal genitalia could not be detected, hence, determination was not volunteered. Follow-up showed that the failure group was equally divided between males and females, emphasizing that lack of visualization did not imply a female perineum. The reasons for failure and success, scanning techniques, and a brief review of fetal genital embryology are discussed. Caution of potential psychological effects on the parents is raised.


Assuntos
Diagnóstico Pré-Natal/métodos , Análise para Determinação do Sexo , Ultrassonografia , Erros de Diagnóstico , Feminino , Idade Gestacional , Humanos , Masculino , Pênis , Períneo , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Escroto , Testículo
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