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1.
AIDS Behav ; 28(6): 2054-2077, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38441698

RESUMO

Stigma against sexual and gender minorities (SGM) populations has serious negative health effects for SGM populations. Despite the growing need for accurate stigma measurement in SGM, there are insufficient valid measurement instruments. Moreover, the lack of consistency in construct usage makes comparisons across studies particularly challenging. A critical review and comparative evaluation of the psychometric properties of the various stigma measures for SGM is necessary to advance our understanding regarding stigma measurement against/among SGMs. Based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a comprehensive search was conducted in 4 bibliographic databases (MEDLINE, PsycINFO, CINAHL, and Web of Science) for empirical articles published from 2010 to 2022 that evaluated the psychometrics properties of measurement instruments assessing stigma against SGMs. The screening, extraction, and scoring of the psychometric properties and methodological quality of selected instruments were performed by following the established standards and COSMIN (Consensus-based Standards for the selection of health Measurement Instruments) checklist, respectively. Of the 2031 studies identified, 19 studies were included that reported psychometric properties of 17 measurement instruments. All instruments, except two, were developed for SGMs (n = 15/17). Most instruments included men who have sex with men (MSM) or gay men (n = 11/15), whereas less than half of the instruments assessed stigma among SGM women (n = 6/15). Internal consistency (Cronbach's alpha) and content validity was reported for all instruments (n = 17); construct and structural validity was also reported for majority of the instruments (n = 15 and 10, respectively). However, test-retest reliability and criterion validity was reported for very few instruments (n = 5 each). Based on the COSMIN checklist, we identified the most psychometrically and methodologically robust instruments for each of the five stigma types: combined stigma, enacted stigma, internalized stigma, intersectional stigma, and perceived stigma. For each stigma type, except anticipated stigma, at least one instrument demonstrated strong promise for use in empirical research; however, the selection of instrument depends on the target population and context of the study. Findings indicated a growing use of instruments assessing multiple stigma types. Future studies need to develop intersectional stigma instruments that account for the multiple and intersecting social identities of SGMs. Additionally, most existing instruments would benefit from further psychometric testing, especially on test-retest reliability, criterion validity, adaptability to different LGBTQIA + populations and cultures.


Assuntos
Psicometria , Minorias Sexuais e de Gênero , Estigma Social , Humanos , Minorias Sexuais e de Gênero/psicologia , Reprodutibilidade dos Testes , Inquéritos e Questionários/normas , Masculino , Feminino
2.
Ear Hear ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38783422

RESUMO

Editor's Note: The following article discusses the timely topic Clinical Guidance in the areas of Evidence-Based Early Hearing Detection and Intervention Programs. This article aims to discuss areas of services needed, guidance to countries/organizations attempting to initiate early hearing detection and intervention systems. Expert consensus and systematic/scoping reviews were combined to produce recommendations for evidence-based clinical practice. In Ear and Hearing, our long-term goal for the Point of View article is to stimulate the field's interest in and to enhance the appreciation of the author's area of expertise. Hearing is an important sense for children to develop cognitive, speech, language, and psychosocial skills. The goal of universal newborn hearing screening is to enable the detection of hearing loss in infants so that timely health and educational/therapeutic intervention can be provided as early as possible to improve outcomes. While many countries have implemented universal newborn hearing screening programs, many others are yet to start. As hearing screening is only the first step to identify children with hearing loss, many follow-up services are needed to help them thrive. However, not all of these services are universally available, even in high-income countries. The purposes of this article are (1) to discuss the areas of services needed in an integrated care system to support children with hearing loss and their families; (2) to provide guidance to countries/organizations attempting to initiate early hearing detection and intervention systems with the goal of meeting measurable benchmarks to assure quality; and (3) to help established programs expand and improve their services to support children with hearing loss to develop their full potential. Multiple databases were interrogated including PubMed, Medline (OVIDSP), Cochrane library, Google Scholar, Web of Science and One Search, ERIC, PsychInfo. Expert consensus and systematic/scoping reviews were combined to produce recommendations for evidence-based clinical practice. Eight essential areas were identified to be central to the integrated care: (1) hearing screening, (2) audiologic diagnosis and management, (3) amplification, (4) medical evaluation and management, (5) early intervention services, (6) family-to-family support, (7) D/deaf/hard of hearing leadership, and (8) data management. Checklists are provided to support the assessment of a country/organization's readiness and development in each area as well as to suggest alternative strategies for situations with limited resources. A three-tiered system (i.e., Basic, Intermediate, and Advanced) is proposed to help countries/organizations at all resource levels assess their readiness to provide the needed services and to improve their integrated care system. Future directions and policy implications are also discussed.

3.
Mol Ecol ; 32(18): 4953-4970, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37566208

RESUMO

Understanding how interactions among microevolutionary forces generate genetic population structure of exploited species is vital to the implementation of management policies that facilitate persistence. Philopatry displayed by many coastal shark species can impact gene flow and facilitate selection, and has direct implications for the spatial scales of management. Here, genetic structure of the blacktip shark (Carcharhinus limbatus) was examined using a mixed-marker approach employing mitochondrial control region sequences and 4339 SNP-containing loci generated using ddRAD-Seq. Genetic variation was assessed among young-of-the-year sampled in 11 sites in waters of the United States in the western North Atlantic Ocean, including the Gulf of Mexico. Spatial and environmental analyses detected 68 nuclear loci putatively under selection, enabling separate assessments of neutral and adaptive genetic structure. Both mitochondrial and neutral SNP data indicated three genetically distinct units-the Atlantic, eastern Gulf, and western Gulf-that align with regional stocks and suggest regional philopatry by males and females. Heterogeneity at loci putatively under selection, associated with temperature and salinity, was observed among sites within Gulf units, suggesting local adaptation. Furthermore, five pairs of siblings were identified in the same site across timescales corresponding with female reproductive cycles. This indicates that females re-used a site for parturition, which has the potential to facilitate the sorting of adaptive variation among neighbouring sites. The results demonstrate differential impacts of microevolutionary forces at varying spatial scales and highlight the importance of conserving essential habitats to maintain sources of adaptive variation that may buffer species against environmental change.


Assuntos
Genética Populacional , Tubarões , Animais , Masculino , Feminino , Haplótipos/genética , Oceano Atlântico , Tubarões/genética , Estruturas Genéticas
4.
Conserv Biol ; 35(3): 991-1001, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33538362

RESUMO

Developing-world shark fisheries are typically not assessed or actively managed for sustainability; one fundamental obstacle is the lack of species and size-composition catch data. We tested and implemented a new and potentially widely applicable approach for collecting these data: mandatory submission of low-value secondary fins (anal fins) from landed sharks by fishers and use of the fins to reconstruct catch species and size. Visual and low-cost genetic identification were used to determine species composition, and linear regression was applied to total length and anal fin base length for catch-size reconstruction. We tested the feasibility of this approach in Belize, first in a local proof-of-concept study and then scaling it up to the national level for the 2017-2018 shark-fishing season (1,786 fins analyzed). Sixteen species occurred in this fishery. The most common were the Caribbean reef (Carcharhinus perezi), blacktip (C. limbatus), sharpnose (Atlantic [Rhizoprionodon terraenovae] and Caribbean [R. porosus] considered as a group), and bonnethead (Sphyrna cf. tiburo). Sharpnose and bonnethead sharks were landed primarily above size at maturity, whereas Caribbean reef and blacktip sharks were primarily landed below size at maturity. Our approach proved effective in obtaining critical data for managing the shark fishery, and we suggest the tools developed as part of this program could be exported to other nations in this region and applied almost immediately if there were means to communicate with fishers and incentivize them to provide anal fins. Outside the tropical Western Atlantic, we recommend further investigation of the feasibility of sampling of secondary fins, including considerations of time, effort, and cost of species identification from these fins, what secondary fin type to use, and the means with which to communicate with fishers and incentivize participation. This program could be a model for collecting urgently needed data for developing-world shark fisheries globally. Article impact statement: Shark fins collected from fishers yield data critical to shark fisheries management in developing nations.


Uso de Aletas Secundarias Proporcionadas por Pescadores para Llenar Vacíos Importantes de Información sobre las Pesquerías de Tiburones Resumen Con frecuencia no se evalúan las pesquerías de tiburones del mundo en desarrollo ni cuentan con un manejo activo de sustentabilidad. Uno de los principales obstáculos para esto es la falta de información sobre las especies y la composición de los tamaños en las capturas. Probamos e implementamos una estrategia nueva y potencialmente aplicable en todas partes para la recolección de estos datos: la entrega obligatoria de las aletas secundarias de bajo valor económico (aletas anales) obtenidas de los tiburones desembarcados por parte de los pescadores y el uso de estas aletas para reconstruir las especies y tamaños en la captura. Usamos identificaciones genéticas de bajo costo e identificaciones visuales para determinar la composición de las especies y aplicamos una regresión lineal a la longitud total y a la de la base de la aleta anal para la reconstrucción del tamaño en captura. Probamos la viabilidad de esta estrategia en Belice, primero en un estudio de prueba de concepto y después subiendo al nivel nacional para la temporada de pesca de tiburón 2017-2018 (1,786 aletas analizadas). Se registraron 16 especies en esta pesquería. Las más comunes fueron Carcharhinus perezi, C. limbatus, Rhizoprionodon terraenovae y R. porosus (consideradas como un grupo) y Sphyrna cf. tiburo. Las últimas tres especies fueron desembarcadas principalmente por encima del tamaño maduro, mientras que con las dos primeras especies lo hacían por debajo del tamaño maduro. Nuestra estrategia demostró ser efectiva en la obtención de información crítica para el manejo de la pesquería de tiburones y sugerimos que las herramientas desarrolladas como parte de este programa puedan ser exportadas a otras naciones en esta región y aplicadas casi de manera inmediata si existen los medios para comunicarse con los pescadores e incentivarlos a proporcionar las aletas anales. Fuera del Atlántico Occidental tropical, recomendamos una mayor investigación de la viabilidad del muestreo de aletas secundarias, incluyendo la consideración del tiempo, esfuerzo y costo de la identificación de especies a partir de estas aletas; cuál tipo de aleta secundaria utilizar; y los medios mediante los cuales comunicarse con los pescadores e incentivarlos a participar. Este programa podría ser un modelo para la recolección de información de necesidad urgente para las pesquerías del mundo en desarrollo.


Assuntos
Mustelidae , Tubarões , Animais , Conservação dos Recursos Naturais , Pesqueiros , Alimentos Marinhos
5.
BMC Genomics ; 19(1): 163, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29471804

RESUMO

BACKGROUND: Southern flounder, Paralichthys lethostigma, historically support a substantial fishery along the Atlantic and Gulf coasts of the southern United States. Low year-class strengths over the past few years in the western Gulf of Mexico have raised concern that spawning stocks may be overfished. Current management of the resource includes releasing hatchery-raised juveniles to restock bays and estuaries; additionally, there is a growing interest in the potential for commercial aquaculture of the species. Currently, genomic resources for southern flounder do not exist. Here, we used two hatchery-reared families and double-digest, restriction-site-associated DNA (ddRAD) sequencing to create a reduced-representation genomic library consisting of several thousand single nucleotide polymorphisms (SNPs) located throughout the genome. RESULTS: The relative position of each SNP-containing locus was determined to create a high-density genetic map spanning the 24 linkage groups of the southern flounder genome. The consensus map was used to identify regions of shared synteny between southern flounder and seven other fish species for which genome assemblies are available. Finally, syntenic blocks were used to localize genes identified from transcripts in European flounder as potentially being involved in ecotoxicological and osmoregulatory responses, as well as QTLs associated with growth and disease resistance in Japanese flounder, on the southern flounder linkage map. CONCLUSIONS: The information provided by the linkage map will enrich restoration efforts by providing a foundation for interpreting spatial genetic variation within the species, ultimately furthering an understanding of the adaptive potential and resilience of southern flounder to future changes in local environmental conditions. Further, the map will facilitate the use of genetic markers to enhance restoration and commercial aquaculture.


Assuntos
Mapeamento Cromossômico/métodos , Linguado/genética , Genômica/métodos , Polimorfismo de Nucleotídeo Único , Animais , Meio Ambiente , Ligação Genética , Marcadores Genéticos , Variação Genética , Genoma , Locos de Características Quantitativas , Análise de Sequência de DNA , Sintenia
6.
Mol Ecol ; 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29987880

RESUMO

Sequencing reduced-representation libraries of restriction site-associated DNA (RADseq) to identify single nucleotide polymorphisms (SNPs) is quickly becoming a standard methodology for molecular ecologists. Because of the scale of RADseq data sets, putative loci cannot be assessed individually, making the process of filtering noise and correctly identifying biologically meaningful signal more difficult. Artefacts introduced during library preparation and/or bioinformatic processing of SNP data can create patterns that are incorrectly interpreted as indicative of population structure or natural selection. Therefore, it is crucial to carefully consider types of errors that may be introduced during laboratory work and data processing, and how to minimize, detect and remove these errors. Here, we discuss issues inherent to RADseq methodologies that can result in artefacts during library preparation and locus reconstruction resulting in erroneous SNP calls and, ultimately, genotyping error. Further, we describe steps that can be implemented to create a rigorously filtered data set consisting of markers accurately representing independent loci and compare the effect of different combinations of filters on four RAD data sets. At last, we stress the importance of publishing raw sequence data along with final filtered data sets in addition to detailed documentation of filtering steps and quality control measures.

7.
J Hered ; 106(3): 258-65, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25762777

RESUMO

The white shark, Carcharodon carcharias, is both one of the largest apex predators in the world and among the most heavily protected marine fish. Population genetic diversity is in part shaped by recent demographic history and can thus provide information complementary to more traditional population assessments, which are difficult to obtain for white sharks and have at times been controversial. Here, we use the mitochondrial control region and 14 nuclear-encoded microsatellite loci to assess white shark genetic diversity in 2 regions: the Northwest Atlantic (NWA, N = 35) and southern Africa (SA, N = 131). We find that these 2 regions harbor genetically distinct white shark populations (Φ ST = 0.10, P < 0.00001; microsatellite F ST = 0.1057, P < 0.021). M-ratios were low and indicative of a genetic bottleneck in the NWA (M-ratio = 0.71, P < 0.004) but not SA (M-ratio = 0.85, P = 0.39). This is consistent with other evidence showing a steep population decline occurring in the mid to late 20th century in the NWA, whereas the SA population appears to have been relatively stable. Estimates of effective population size ranged from 22.6 to 66.3 (NWA) and 188 to 1998.3 (SA) and evidence of inbreeding was found (primarily in NWA). Overall, our findings indicate that white population dynamics within NWA and SA are determined more by intrinsic reproduction than immigration and there is genetic evidence of a population decline in the NWA, further justifying the strong domestic protective measures that have been taken for this species in this region. Our study also highlights how assessment of genetic diversity can complement other sources of information to better understand the status of threatened marine fish populations.


Assuntos
Variação Genética , Genética Populacional , Tubarões/genética , África Austral , Animais , Oceano Atlântico , DNA Mitocondrial/genética , Feminino , Haplótipos , Endogamia , Masculino , Repetições de Microssatélites , Dinâmica Populacional , Análise de Sequência de DNA
8.
Evol Appl ; 17(6): e13705, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38832083

RESUMO

Intraspecific diversity plays a critical role in the resilience of Chinook salmon populations. California's Central Valley (CV) historically hosted one of the most diverse population complexes of Chinook salmon in the world. However, anthropogenic factors have dramatically decreased this diversity, with severe consequences for population resilience. Here we use next generation sequencing and an archive of thousands of tissue samples collected across two decades during the juvenile outmigration to evaluate phenotypic diversity between and within populations of CV Chinook salmon. To account for highly heterogeneous sample qualities in the archive dataset, we develop and test an approach for population and subpopulation assignments of CV Chinook salmon that allows inclusion of relatively low-quality samples while controlling error rates. We find significantly distinct outmigration timing and body size distributions for each population and subpopulation. Within the archive dataset, spring run individuals that assigned to the Mill and Deer Creeks subpopulation exhibited an earlier and broader outmigration distribution as well as larger body sizes than individuals that assigned to the Butte Creek subpopulation. Within the fall run population, individuals that assigned to the late-fall run subpopulation also exhibited an earlier and broader outmigration distribution and larger body sizes than other fall run fish in our dataset. These results highlight the importance of distinct subpopulations for maintaining remaining diversity in CV Chinook salmon, and demonstrates the power of genomics-based population assignments to aid the study and management of intraspecific diversity.

9.
Ecol Evol ; 14(6): e11514, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38859886

RESUMO

Patterns of genetic variation reflect interactions among microevolutionary forces that vary in strength with changing demography. Here, patterns of variation within and among samples of the mouthbrooding gafftopsail catfish (Bagre marinus, Family Ariidae) captured in the U.S. Atlantic and throughout the Gulf of Mexico were analyzed using genomics to generate neutral and non-neutral SNP data sets. Because genomic resources are lacking for ariids, linkage disequilibrium network analysis was used to examine patterns of putatively adaptive variation. Finally, historical demographic parameters were estimated from site frequency spectra. The results show four differentiated groups, corresponding to the (1) U.S. Atlantic, and the (2) northeastern, (3) northwestern, and (4) southern Gulf of Mexico. The non-neutral data presented two contrasting signals of structure, one due to increases in diversity moving west to east and north to south, and another to increased heterozygosity in the Atlantic. Demographic analysis suggested that recently reduced long-term effective population size in the Atlantic is likely an important driver of patterns of genetic variation and is consistent with a known reduction in population size potentially due to an epizootic. Overall, patterns of genetic variation resemble that of other fishes that use the same estuarine habitats as nurseries, regardless of the presence/absence of a larval phase, supporting the idea that adult/juvenile behavior and habitat are important predictors of contemporary patterns of genetic structure.

10.
Ecol Evol ; 11(19): 13415-13429, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34646479

RESUMO

Interpreting contemporary patterns of population structure requires an understanding of the interactions among microevolutionary forces and past demographic events. Here, 4,122 SNP-containing loci were used to assess structure in southern flounder (Paralichthys lethostigma) sampled across its range in the US Atlantic Ocean (Atlantic) and Gulf of Mexico (Gulf) and relationships among components of genomic variation and spatial and environmental variables were assessed across estuarine population samples in the Gulf. While hierarchical amova revealed significant heterogeneity within and between the Atlantic and Gulf, pairwise comparisons between samples within ocean basins demonstrated that all significant heterogeneity occurred within the Gulf. The distribution of Tajima's D estimated at a genome-wide scale differed significantly from equilibrium in all estuaries, with more negative values occurring in the Gulf. Components of genomic variation were significantly associated with environmental variables describing individual estuaries, and environment explained a larger component of variation than spatial proximity. Overall, results suggest that there is genetic spatial autocorrelation caused by shared larval sources for proximal nurseries (migration/drift), but that it is modified by environmentally driven differentiation (selection). This leads to conflicting signals in different parts of the genome and creates patterns of divergence that do not correspond to paradigms of strong local directional selection.

11.
PLoS One ; 8(6): e66126, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762473

RESUMO

In contrast to freshwater fish it is presumed that marine fish are unlikely to spawn with close relatives due to the dilution effect of large breeding populations and their propensity for movement and reproductive mixing. Inbreeding is therefore not typically a focal concern of marine fish management. We measured the effective number of breeders in 6 New York estuaries for winter flounder (Pseudopleuronectes americanus), a formerly abundant fish, using 11 microsatellite markers (6-56 alleles per locus). The effective number of breeders for 1-2 years was remarkably small, with point estimates ranging from 65-289 individuals. Excess homozygosity was detected at 10 loci in all bays (FIS = 0.169-0.283) and individuals exhibited high average internal relatedness (IR; mean = 0.226). These both indicate that inbreeding is very common in all bays, after testing for and ruling out alternative explanations such as technical and sampling artifacts. This study demonstrates that even historically common marine fish can be prone to inbreeding, a factor that should be considered in fisheries management and conservation plans.


Assuntos
Peixes/crescimento & desenvolvimento , Endogamia , Água do Mar , Alelos , Animais , Baías , Intervalos de Confiança , Peixes/genética , Loci Gênicos/genética , Variação Genética , Geografia , Heterozigoto , Repetições de Microssatélites/genética , New York , Tamanho da Amostra
12.
Psychopharmacology (Berl) ; 223(1): 37-45, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22427020

RESUMO

BACKGROUND: Soda manufacturers claim that caffeine is added to soda as a flavor enhancer, but many researchers have speculated that caffeine is added to increase the hedonic and reinforcing properties of the soda. Studies in adults have demonstrated that caffeine can condition flavor preferences when added to novel-flavored beverages. OBJECTIVES: The purpose of this study was to test the hypothesis that caffeine added to novel-flavored drinks would increase liking and preference in adolescents. METHODS: Adolescents (n = 99) between the ages of 12 and 17 rated and ranked seven novel soda drinks. They were then randomly assigned to consume one of these beverages paired with either caffeine (1 or 2 mg/kg) or placebo over four consecutive days and rate liking. On the final visit, participants retasted the seven beverages and provided hedonic ratings and rankings. RESULTS: Participants in the 2-mg/kg caffeine group increased the liking of the beverage over the exposure period after an initial decrease, but there was no change in liking for those in the placebo group or in the 1-mg/kg group. The increase in liking in the 2-mg/kg group was accompanied by a decrease in perceived bitterness, but no change in beverage ranking or consumption during the post-test. CONCLUSIONS: Caffeine added to novel beverages results in a decrease in liking followed by an increase in liking with repeated exposures that may result from habituation to the bitterness of caffeine. Change in bitter perception may be the mechanism by which adolescents establish regular caffeine use.


Assuntos
Bebidas , Cafeína/administração & dosagem , Preferências Alimentares , Paladar , Adolescente , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Reforço Psicológico
13.
Opt Lett ; 32(5): 569-71, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17392924

RESUMO

Coherent Zeeman resonance from electron spin coherence is demonstrated in a Lambda-type three-level system, coupling electron spin states via trions. The optical control of electron density that is characteristic of a mixed-type quantum-well facilitates the study of trion formation as well as the effects of many-body interactions on the manifestation of electron spin coherence in the nonlinear optical response.

14.
Biochemistry ; 44(15): 5774-87, 2005 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-15823036

RESUMO

When the nonfluorescent chromoprotein asFP595 from Anemonia sulcata is subjected to sufficiently intense illumination near the absorbance maximum (lambda(abs)(max) = 568 nm), it undergoes a remarkable transition, termed "kindling", to a long-lived fluorescent state (lambda(em)(max) = 595 nm). In the dark recovery phase, the kindled state relaxes thermally on a time scale of seconds or can instantly be reverted upon illumination at 450 nm. The kindling phenomenon is enhanced by the Ala143 --> Gly point mutation, which slows the dark recovery time constant to 100 s at room temperature and increases the fluorescence quantum yield. To investigate the chemical nature of the chromophore and the possible role of chromophore isomerization in the kindling phenomenon, we determined the crystal structure of the "kindling fluorescent protein" asFP595-A143G (KFP) in the dark-adapted state at 1.38 A resolution and 100 K. The chromophore, derived from the Met63-Tyr64-Gly65 tripeptide, closely resembles that of the nonfluorescent chromoprotein Rtms5 in that the configuration is trans about the methylene bridge and there is substantial distortion from planarity. Unlike in Rtms5, in the native protein the polypeptide backbone is cleaved between Cys62 and Met63. The size and shape of the chromophore pocket suggest that the cis isomer of the chromophore could also be accommodated. Within the pocket, partially disordered His197 displays two conformations, which may constitute a binary switch that stabilizes different chromophore configurations. The energy barrier for thermal relaxation was found by Arrhenius plot analysis to be approximately 71 kJ/mol, somewhat higher than the value of approximately 55 kJ/mol observed for cis-trans isomerization of a model chromophore in solution.


Assuntos
Proteínas Luminescentes/química , Anêmonas-do-Mar/química , Substituição de Aminoácidos , Animais , Cristalografia por Raios X , Escuridão , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/efeitos da radiação , Luz , Proteínas Luminescentes/genética , Proteínas Luminescentes/efeitos da radiação , Modelos Moleculares , Estrutura Molecular , Mutação Puntual , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/efeitos da radiação , Anêmonas-do-Mar/genética , Eletricidade Estática , Termodinâmica
15.
Psicológica (Valencia, Ed. impr.) ; 26(1): 7-24, ene.- jun. 2005. ilus, tab
Artigo em En | IBECS (Espanha) | ID: ibc-044014

RESUMO

When navigating by path integration, knowledge of one’s position becomesincreasingly uncertain as one walks from a known location. Thisuncertainty decreases if one perceives a known landmark location nearby.We hypothesized that remembering landmarks might serve a similar purposefor path integration as directly perceiving them. If this is true, walking neara remembered landmark location should enhance response consistency inpath integration tasks. To test this, we asked participants to view a targetand then attempt to walk to it without vision. Some participants saw thetarget plus a landmark during the preview. Compared with no-landmarktrials, response consistency nearly doubled when participants passed near theremembered landmark location. Similar results were obtained whenparticipants could audibly perceive the landmark while walking. A controlexperiment ruled out perceptual context effects during the preview. Weconclude that remembered landmarks can enhance path integration eventhough they are not directly perceived


Assuntos
Humanos , Percepção Espacial , Percepção de Distância , Imagem Eidética , Visão Ocular/fisiologia , Locomoção/fisiologia
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