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1.
Mem Cognit ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668990

RESUMO

Cognitive control processes are central to adaptive behavior, but how control is applied in a context-appropriate manner is not fully understood. One way to produce context-sensitive control is by mnemonically linking particular control settings to specific stimuli that demanded those settings in a prior encounter. In support of this episodic reinstatement of control hypothesis, recent studies have produced evidence for the formation of stimulus-control associations in one-shot, prime-probe learning paradigms. However, since those studies employed perceptually identical stimuli across prime and probe presentations, it is not yet known how generalizable one-shot stimulus-control associations are. In the current study, we therefore probed whether associations formed between a prime object and the control process of task-switching would generalize to probe objects seen from a different viewpoint (Experiment 1), to different exemplars of the same object type (Experiment 2), and to different members of the object category (Experiment 3). We replicated prior findings of one-shot control associations for identical prime/probe stimuli. Importantly, we additionally found that these episodic control effects are expressed regardless of changes in viewpoint and exemplar, but do not seem to generalize to other category members. These findings elucidate the scope of generalization of the episodic reinstatement of cognitive control.

2.
J Cogn ; 5(1): 26, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072115

RESUMO

It has been proposed that cognitive control processes may be implemented in a contextually appropriate manner through the encoding, and cued retrieval, of associations between stimuli and the control processes that were active during their encoding, forming "stimulus-control bindings" as part of episodic event files. Prior work has found strong evidence for such a mechanism by observing behavioral effects of stimulus-control bindings based on a single pairing (one-shot learning). Here, we addressed the important question of how durable these one-shot stimulus-control bindings are. Over three experiments, we investigated the durability of one-shot stimulus-control bindings in relation to both the passage of time and the number of intervening events between the encoding (prime) and retrieval (probe) of the stimulus-control bindings. We found that stimulus-control bindings are quite robust to temporal decay, lasting at least up to 5 minutes in the absence of similar intervening events. By contrast, binding effects were more short-lived in the face of interference from the encoding of similar events between the prime and probe, with a maximum duration of ~2 minutes. Together, these results shed new light on the characteristics of the binding mechanisms underlying the integration of internal control processes in episodic event files and highlight that interference, rather than temporal decay, may be the main limiting factor on long-term effects of item-specific one-shot control learning.

3.
Psychon Bull Rev ; 29(5): 1997-2007, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35477849

RESUMO

Much of our day is spent mind-wandering-periods of inattention characterized by a lack of awareness of external stimuli and information. Whether we are paying attention or not, information surrounds us constantly-some true and some false. The proliferation of false information in news and social media highlights the critical need to understand the psychological mechanisms underlying our beliefs about what is true. People often rely on heuristics to judge the truth of information. For example, repeated information is more likely to be judged as true than new information (i.e., the illusory truth effect). However, despite the prevalence of mind wandering in our daily lives, current research on the contributing factors to the illusory truth effect have largely ignored periods of inattention as experimentally informative. Here, we aim to address this gap in our knowledge, investigating whether mind wandering during initial exposure to information has an effect on later belief in the truth of that information. That is, does the illusory truth effect occur even when people report not paying attention to the information at hand. Across three studies we demonstrate that even during periods of mind wandering, the repetition of information increases truth judgments. Further, our results suggest that the severity of mind wandering moderated truth ratings, such that greater levels of mind wandering decreased truth judgements for previously presented information.


Assuntos
Julgamento , Humanos
4.
Psychon Bull Rev ; 29(3): 1035-1044, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34918273

RESUMO

Learning often happens in ideal conditions, but then must be applied in less-than-ideal conditions - such as when a learner studies clearly illustrated examples of rocks in a book but then must identify them in a muddy field. Here we examine whether the benefits of interleaving (vs. blocking) study schedules, as well as the use of feature descriptions, supports the transfer of category learning in new, impoverished contexts. Specifically, keeping the study conditions constant, we evaluated learners' ability to classify new exemplars in the same neutral context versus in impoverished contexts in which certain stimulus features are occluded. Over two experiments, we demonstrate that performance in new, impoverished contexts during test is greater for participants who received an interleaved (vs. blocked) study schedule, both for novel and for studied exemplars. Additionally, we show that this benefit extends to both a short (3-min) or long (48-h) test delay. The presence of feature descriptions during learning had no impact on transfer. Together, these results extend the growing literature investigating how changes in context during category learning or test impacts performance and provide support for the use of interleaving to promote the far transfer of category knowledge to impoverished contexts.


Assuntos
Formação de Conceito , Aprendizagem , Humanos
5.
Atten Percept Psychophys ; 83(7): 2968-2982, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34322789

RESUMO

The one-shot pairing of a stimulus with a specific cognitive control process, such as task switching, can bind the two together in memory. The episodic control-binding hypothesis posits that the formation of temporary stimulus-control bindings, which are held in event-files supported by episodic memory, can guide the contextually appropriate application of cognitive control. Across two experiments, we sought to examine the role of task-focused attention in the encoding and implementation of stimulus-control bindings in episodic event-files. In Experiment 1, we obtained self-reports of mind wandering during encoding and implementation of stimulus-control bindings. Results indicated that, whereas mind wandering during the implementation of stimulus-control bindings does not decrease their efficacy, mind wandering during the encoding of these control-state associations interferes with their successful deployment at a later point. In Experiment 2, we complemented these results by using trial-by-trial pupillometry to measure attention, again demonstrating that attention levels at encoding predict the subsequent implementation of stimulus-control bindings better than attention levels at implementation. These results suggest that, although encoding stimulus-control bindings in episodic memory requires active attention and engagement, once encoded, these bindings are automatically deployed to guide behavior when the stimulus recurs. These findings expand our understanding of how cognitive control processes are integrated into episodic event files.


Assuntos
Aprendizagem , Memória Episódica , Atenção , Humanos
6.
Exp Psychol ; 67(5): 303-313, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33274657

RESUMO

Recent work in attentional control has suggested that conflict effects measured across different tasks are not reliable and by extension unrelated. The lack of correlation between these conflict effects is in juxtaposition not only to theoretical predictions of a domain-general attentional control mechanism but also to a large body of individual differences research that has used these tasks to show evidence for an attentional control construct and its relatedness to other psychological constructs. In an effort to address this, we fit hierarchical models to each task that modeled trial-to-trial variability in response times to assess the extent to which the parameter estimates for the conflict effect correlated across tasks. We compared this method of assessing shared variance to more traditional summed difference score estimates of the conflict effect by analyzing data from a large-scale individual differences experiment, in which N = 582 subjects completed a Stroop, Flanker, and Simon task. Across tasks, we found that while the reliability of the conflict was sufficiently high and the between-task conflict effect significantly correlated, the magnitude of the between-task correlation was low. We discuss the implications of these results as providing more support for a domain-specific than domain-general attentional control mechanism.


Assuntos
Conflito Psicológico , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Reprodutibilidade dos Testes
7.
Cognition ; 199: 104220, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32065944

RESUMO

The repeated pairing of a particular stimulus with a specific cognitive control process, such as task switching, can bind the two together in memory, resulting in the formation of stimulus-control associations. These bindings are thought to guide the context-sensitive application of cognitive control, but it is not presently known whether such stimulus-control associations are only acquired through slow, incremental learning or could also be mediated by episodic memories of a single experience, so-called one-shot learning. Here, we tested this episodic control-binding hypothesis by probing whether a single co-occurrence of a stimulus and the control process of task switching would lead to significant performance benefits (reduced task switch cost) when that stimulus later re-occurred under the same as opposed to different control demands. Across three experiments, we demonstrate that item-specific stimulus-control associations can be formed based on a single exposure, providing the first strong evidence for episodic memory guidance of cognitive control.


Assuntos
Aprendizagem , Memória Episódica , Humanos
8.
J Cogn Neurosci ; 31(7): 1079-1090, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30938591

RESUMO

The contents of working memory (WM) guide visual attention toward matching features, with visual search being faster when the target and a feature of an item held in WM spatially overlap (validly cued) than when they occur at different locations (invalidly cued). Recent behavioral studies have indicated that attentional capture by WM content can be modulated by cognitive control: When WM cues are reliably helpful to visual search (predictably valid), capture is enhanced, but when reliably detrimental (predictably invalid), capture is attenuated. The neural mechanisms underlying this effect are not well understood, however. Here, we leveraged the high temporal resolution of ERPs time-locked to the onset of the search display to determine how and at what processing stage cognitive control modulates the search process. We manipulated predictability by grouping trials into unpredictable (50% valid/invalid) and predictable (100% valid, 100% invalid) blocks. Behavioral results confirmed that predictability modulated WM-related capture. Comparison of ERPs to the search arrays showed that the N2pc, a posteriorly distributed signature of initial attentional orienting toward a lateralized target, was not impacted by target validity predictability. However, a longer latency, more anterior, lateralized effect-here, termed the "contralateral attention-related negativity"-was reduced under predictable conditions. This reduction interacted with validity, with substantially greater reduction for invalid than valid trials. These data suggest cognitive control over attentional capture by WM content does not affect the initial attentional-orienting process but can reduce the need to marshal later control mechanisms for processing relevant items in the visual world.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Função Executiva/fisiologia , Memória de Curto Prazo/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Sinais (Psicologia) , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Tempo de Reação , Adulto Jovem
9.
PLoS One ; 14(1): e0210528, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30650155

RESUMO

Genetic analyses provide a powerful tool with which to identify the biological components of historical objects. Te Tiriti o Waitangi | The Treaty of Waitangi is New Zealand's founding document, intended to be a partnership between the indigenous Maori and the British Crown. Here we focus on an archived piece of blank parchment that has been proposed to be the missing portion of the lower parchment of the Waitangi Sheet of the Treaty. However, its physical dimensions and characteristics are not consistent with this hypothesis. We perform genetic analyses on the parchment membranes of the Treaty, plus the blank piece of parchment. We find that all three parchments were made from ewes and that the blank parchment is highly likely to be a portion cut from the lower membrane of the Waitangi Sheet because they share identical whole mitochondrial genomes, including an unusual heteroplasmic site. We suggest that the differences in size and characteristics between the two pieces of parchment may have resulted from the Treaty's exposure to water in the early 20th century and the subsequent repair work, light exposure during exhibition or the later conservation treatments in the 1970s and 80s. The blank piece of parchment will be valuable for comparison tests to study the effects of earlier treatments and to monitor the effects of long-term display on the Treaty.


Assuntos
Equidade em Saúde/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Serviços de Saúde do Indígena/legislação & jurisprudência , Cooperação Internacional , Animais , Identificação Biométrica/métodos , DNA Mitocondrial/classificação , DNA Mitocondrial/isolamento & purificação , Feminino , Testes Genéticos/métodos , Genoma Mitocondrial/genética , Humanos , Nova Zelândia , Filogenia , Ovinos/genética , Reino Unido
10.
PLoS One ; 14(1): e0210736, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30645634

RESUMO

The visual color-word Stroop task is widely used in clinical and research settings as a measure of cognitive control. Numerous neuroimaging studies have used color-word Stroop tasks to investigate the neural resources supporting cognitive control, but to our knowledge all have used unimodal (typically visual) Stroop paradigms. Thus, it is possible that this classic measure of cognitive control is not capturing the resources involved in multisensory cognitive control. The audiovisual integration and crossmodal correspondence literatures identify regions sensitive to congruency of auditory and visual stimuli, but it is unclear how these regions relate to the unimodal cognitive control literature. In this study we aimed to identify brain regions engaged by crossmodal cognitive control during an audiovisual color-word Stroop task, and how they relate to previous unimodal Stroop and audiovisual integration findings. First, we replicated previous behavioral audiovisual Stroop findings in an fMRI-adapted audiovisual Stroop paradigm: incongruent visual information increased reaction time towards an auditory stimulus and congruent visual information decreased reaction time. Second, we investigated the brain regions supporting cognitive control during an audiovisual color-word Stroop task using fMRI. Similar to unimodal cognitive control tasks, a left superior parietal region exhibited an interference effect of visual information on the auditory stimulus. This superior parietal region was also identified using a standard audiovisual integration localizing procedure, indicating that audiovisual integration resources are sensitive to cognitive control demands. Facilitation of the auditory stimulus by congruent visual information was found in posterior superior temporal cortex, including in the posterior STS which has been found to support audiovisual integration. The dorsal anterior cingulate cortex, often implicated in unimodal Stroop tasks, was not modulated by the audiovisual Stroop task. Overall the findings indicate that an audiovisual color-word Stroop task engages overlapping resources with audiovisual integration and overlapping but distinct resources compared to unimodal Stroop tasks.


Assuntos
Percepção Auditiva/fisiologia , Imageamento por Ressonância Magnética/métodos , Percepção Visual/fisiologia , Adolescente , Adulto , Feminino , Giro do Cíngulo/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Parietal/fisiologia , Tempo de Reação/fisiologia , Teste de Stroop , Adulto Jovem
11.
J Exp Psychol Learn Mem Cogn ; 45(5): 765-778, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30047768

RESUMO

Recent work on cognitive control focuses on the conflict-monitoring hypothesis, which posits that a performance monitoring mechanism recruits regions in the dorsolateral prefrontal cortex to ensure that goal-directed behavior is optimal. Critical to this theory is that a single performance monitoring mechanism explains a large number of behavioral effects including the sequential congruency effect (SCE) and the error-related slowing (ERS) effect. This leads to the prediction that the size of these effects should correlate across cognitive control tasks. To this end, we conducted three large-scale individual differences experiments to examine whether the SCE and ERS effect are correlated across Simon, Flanker, and Stroop tasks. Across all experiments, the results revealed a correlation for the error-related slowing effect, but not for the sequential congruency effect across tasks. We discuss the implications of these results in regards to the hypothesis that a domain-general performance monitoring mechanism drives both effects. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Cognição , Autocontrole , Conflito Psicológico , Função Executiva , Humanos , Individualidade , Testes Psicológicos , Teoria Psicológica , Tempo de Reação
12.
J Exp Psychol Hum Percept Perform ; 44(12): 1970-1980, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30265022

RESUMO

Recent studies have demonstrated that keeping an instructed task set in working memory (WM) for prospective use can interfere with behavior on an intervening task that employs shared stimuli-the prospective task-set-interference effect. One open question is whether people have strategic control over prospective task-set interference based on their expectations of whether task instructions will have to be implemented or recalled. To answer this question, we conducted two experiments that varied the likelihood with which a set of prospective task instructions would have to be implemented or recalled. Based on the hypothesis that participants are able to strategically modulate the manner in which a prospective task set is encoded in WM, we predicted that, as the frequency of implementing task instructions increased, so too would the magnitude of the prospective task-set-interference effect. We found that task instructions held in WM caused significant task-set interference, even in mostly recall conditions, but-crucially-that this interference effect scaled positively with the likelihood of having to implement the prospective set. These data suggest that task instructions are obligatorily encoded as a procedural task set, but that the degree to which this set impinges on ongoing stimulus processing is subject to some strategic control, possibly via modulation of the associations between declarative and procedural WM contents. (PsycINFO Database Record (c) 2018 APA, all rights reserved).


Assuntos
Atenção/fisiologia , Função Executiva/fisiologia , Objetivos , Memória de Curto Prazo/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Humanos , Masculino , Reconhecimento Visual de Modelos/fisiologia
13.
Acta Psychol (Amst) ; 189: 12-18, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27645133

RESUMO

Recent theories have proposed that contingency learning occurs independent of control processes. These parallel processing accounts propose that behavioral effects originally thought to be products of control processes are in fact products solely of contingency learning. This view runs contrary to conflict-mediated Hebbian-learning models that posit control and contingency learning are parts of an interactive system. In this study we replicate the contingency learning effect and modify it to further test the veracity of the parallel processing accounts in comparison to conflict-mediated Hebbian-learning models. This is accomplished by manipulating conflict to test for an interaction, or lack thereof, between conflict and contingency learning. The results are consistent with conflict-mediated Hebbian-learning in that the addition of conflict reduces the magnitude of the contingency learning effect.


Assuntos
Condicionamento Clássico/fisiologia , Conflito Psicológico , Aprendizagem/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Teste de Stroop , Adulto Jovem
14.
J Exp Psychol Hum Percept Perform ; 44(5): 741-755, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29154623

RESUMO

Recent studies have demonstrated that maintaining task-sets in working memory (WM) for prospective implementation can interfere with performance on an intervening task when the same stimulus requires incompatible responses in the ongoing versus the prospective task. This prospective task-set interference effect has previously been conceptualized as an obligatory process, resulting from instruction-based reflexivity (IBR). However, the extent to which strategic control can be exerted over interference in ongoing behavior from prospective task-sets held in WM has heretofore not been tested directly. To probe for strategic control over this effect, the authors conducted 3 experiments using a common inducer-diagnostic task design that manipulated the proportion compatibility of trials in the ongoing task. They hypothesized that if prospective task-set interference were malleable by control, participants would suppress the influence of the prospective set on ongoing processing when incompatible trials are frequent. Consistent with this prediction, the results show that prospective task-set interference is subject to modulation by strategic control such that the magnitude of interference is reduced, eliminated, or reversed in the presence of frequent incompatible trials. Thus, the influence on ongoing behavior of a prospective task-set held in WM is not obligatory, but subject to strategic control. (PsycINFO Database Record


Assuntos
Atenção/fisiologia , Função Executiva/fisiologia , Memória de Curto Prazo/fisiologia , Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Psychophysiology ; 54(7): 1031-1039, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28349582

RESUMO

The proportion congruency effect refers to the observation that the magnitude of the Stroop effect increases as the proportion of congruent trials in a block increases. Contemporary work shows that proportion effects can be driven by both context and individual items, and are referred to as context-specific proportion congruency (CSPC) and item-specific proportion congruency (ISPC) effects, respectively. The conflict-modulated Hebbian learning account posits that these effects manifest from the same mechanism, while the parallel episodic processing model posits that the ISPC can occur by simple associative learning. Our prior work showed that the neural correlates of the CSPC is an N2 over frontocentral electrode sites approximately 300 ms after stimulus onset that predicts behavioral performance. There is strong consensus in the field that this N2 signal is associated with conflict detection in the medial frontal cortex. The experiment reported here assesses whether the same qualitative electrophysiological pattern of results holds for the ISPC. We find that the spatial topography of the N2 is similar but slightly delayed with a peak onset of approximately 300 ms after stimulus onset. We argue that this provides strong evidence that a single common mechanism-conflict-modulated Hebbian learning-drives both the ISPC and CSPC.


Assuntos
Córtex Cerebral/fisiologia , Conflito Psicológico , Potenciais Evocados , Aprendizagem/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Eletroencefalografia , Humanos , Estimulação Luminosa , Tempo de Reação
16.
PLoS One ; 10(12): e0143426, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26630453

RESUMO

Carbon markets afford potentially useful opportunities for supporting socially and environmentally sustainable land management programs but, to date, have been little applied in globally significant fire-prone savanna settings. While fire is intrinsic to regulating the composition, structure and dynamics of savanna systems, in north Australian savannas frequent and extensive late dry season wildfires incur significant environmental, production and social impacts. Here we assess the potential of market-based savanna burning greenhouse gas emissions abatement and allied carbon biosequestration projects to deliver compatible environmental and broader socio-economic benefits in a highly biodiverse north Australian setting. Drawing on extensive regional ecological knowledge of fire regime effects on fire-vulnerable taxa and communities, we compare three fire regime metrics (seasonal fire frequency, proportion of long-unburnt vegetation, fire patch-size distribution) over a 15-year period for three national parks with an indigenously (Aboriginal) owned and managed market-based emissions abatement enterprise. Our assessment indicates improved fire management outcomes under the emissions abatement program, and mostly little change or declining outcomes on the parks. We attribute improved outcomes and putative biodiversity benefits under the abatement program to enhanced strategic management made possible by the market-based mitigation arrangement. For these same sites we estimate quanta of carbon credits that could be delivered under realistic enhanced fire management practice, using currently available and developing accredited Australian savanna burning accounting methods. We conclude that, in appropriate situations, market-based savanna burning activities can provide transformative climate change mitigation, ecosystem health, and community benefits in northern Australia, and, despite significant challenges, potentially in other fire-prone savanna settings.


Assuntos
Carbono/química , Conservação dos Recursos Naturais/métodos , Desastres/prevenção & controle , Incêndios/prevenção & controle , Austrália , Biodiversidade , Mudança Climática , Ecossistema , Estações do Ano
17.
J Environ Manage ; 86(1): 104-13, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17303315

RESUMO

Information on distribution and relative abundance of species is integral to sustainable management, especially if they are to be harvested for subsistence or commerce. In northern Australia, natural landscapes are vast, centers of population few, access is difficult, and Aboriginal resource centers and communities have limited funds and infrastructure. Consequently defining distribution and relative abundance by comprehensive ground survey is difficult and expensive. This highlights the need for simple, cheap, automated methodologies to predict the distribution of species in use, or having potential for use, in commercial enterprise. The technique applied here uses a Geographic Information System (GIS) to make predictions of probability of occurrence using an inductive modeling technique based on Bayes' theorem. The study area is in the Maningrida region, central Arnhem Land, in the Northern Territory, Australia. The species examined, Cycas arnhemica and Brachychiton diversifolius, are currently being 'wild harvested' in commercial trials, involving sale of decorative plants and use as carving wood, respectively. This study involved limited and relatively simple ground surveys requiring approximately 7 days of effort for each species. The overall model performance was evaluated using Cohen's kappa statistics. The predictive ability of the model for C. arnhemica was classified as moderate and for B. diversifolius as fair. The difference in model performance can be attributed to the pattern of distribution of these species. C. arnhemica tends to occur in a clumped distribution due to relatively short distance dispersal of its large seeds and vegetative growth from long-lived rhizomes, while B. diversifolius seeds are smaller and more widely dispersed across the landscape. The output from analysis predicts trends in species distribution that are consistent with independent on-site sampling for each species and therefore should prove useful in gauging the extent of resource availability. However, some caution needs to be applied as the models tend to over predict presence which is a function of distribution patterns and of other variables operating in the landscape such as fire histories which were not included in the model due to limited availability of data.


Assuntos
Conservação dos Recursos Naturais , Cycas , Malvaceae , Modelos Teóricos , Austrália , Teorema de Bayes , Sistemas de Informação Geográfica
18.
Environ Manage ; 38(3): 463-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16736298

RESUMO

Should north Australia's extensive populations of feral animals be eradicated for conservation, or exploited as a rare opportunity for Indigenous enterprise in remote regions? We examine options for a herd of banteng, a cattle species endangered in its native Asian range but abundant in Garig Gunak Barlu National Park, an Aboriginal land managed jointly by traditional owners and a conservation agency in the Northern Territory of Australia. We reflect on the paradoxes that arise when trying to deal effectively with such complex and contested issues in natural resource management using decision-support tools (ecological-economic models), by identifying the trade-offs inherent in protecting values whilst also providing incomes for Indigenous landowners.


Assuntos
Bovinos/fisiologia , Conservação dos Recursos Naturais/economia , Tomada de Decisões , Ecossistema , Modelos Econômicos , Animais , Ásia , Austrália , Dinâmica Populacional
19.
J Biomed Opt ; 11(2): 024006, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16674196

RESUMO

Early identification of high-risk disease could greatly reduce both mortality and morbidity due to oral cancer. We describe a simple handheld device that facilitates the direct visualization of oral-cavity fluorescence for the detection of high-risk precancerous and early cancerous lesions. Blue excitation light (400 to 460 nm) is employed to excite green-red fluorescence from fluorophores in the oral tissues. Tissue fluorescence is viewed directly along an optical axis collinear with the axis of excitation to reduce inter- and intraoperator variability. This robust, field-of-view device enables the direct visualization of fluorescence in the context of surrounding normal tissue. Results from a pilot study of 44 patients are presented. Using histology as the gold standard, the device achieves a sensitivity of 98% and specificity of 100% when discriminating normal mucosa from severe dysplasia/carcinoma in situ (CIS) or invasive carcinoma. We envisage this device as a suitable adjunct for oral cancer screening, biopsy guidance, and margin delineation.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Medições Luminescentes/instrumentação , Neoplasias Bucais/diagnóstico , Espectrometria de Fluorescência/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Medições Luminescentes/métodos , Miniaturização , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos
20.
J Zoo Wildl Med ; 37(1): 33-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17312809

RESUMO

A surrogacy program to increase the reproductive rate of the critically endangered Victorian brush-tailed rock wallaby (Petrogale penicillata), initially developed in semicaptive conditions, was established in close captivity at Adelaide Zoological Gardens in 1998. Pouch young were removed from their mothers on days 8-20 or 40-45 after parturition and placed onto the teat of a tammar wallaby (Macropus eugenii) or yellow-footed rock wallaby (Petrogale xanthopus xanthopus) surrogate mother. During the early years of the program, mortality of brush-tail pouch young was high (12/16, 75%), both before transfer while still on their mother (5/16) and after transfer to a surrogate mother (7/11). Changing pouch young transfer methodology and improving the health status of the surrogate animals during the later years of the program significantly reduced the mortality of brush-tail pouch young (8/29). Under the new methodology, no mortality of brush-tail pouch young was observed between birth and the time of transfer, (0/29), and after transfer, pouch young mortality rate was eight of 29 (28%). Factors implicated in the improved success of the program included 1) the early transfer (between days 8 and 20) of brush-tail pouch young from mother to surrogate mother, 2) review of the veterinary history and health of the animals selected to act as surrogate mothers, and 3) increased access to grazing pasture for foster mothers. The reproductive rate of the brush-tail females in the later years of the breeding program was sixfold above natural birthing rates. These and other factors important in establishing a breeding program of this nature are discussed.


Assuntos
Criação de Animais Domésticos/métodos , Conservação dos Recursos Naturais , Macropodidae/crescimento & desenvolvimento , Medicina Veterinária/métodos , Animais , Animais Recém-Nascidos , Animais Lactentes , Animais Selvagens , Animais de Zoológico , Conservação dos Recursos Naturais/métodos , Feminino , Macropodidae/fisiologia , Masculino
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