Age-related deficits in attentional control of perceptual rivalry

AbstractSome aspects of attentional processing are known to decline with normal aging. To understand how age affects the attentional control of perceptual stability, we investigated age-related changes in voluntarily controlled perceptual rivalry. Durations of the dominant percept, produced by an ambiguous Rubin vase-faces figure, were measured in conditions that required passive viewing and attentional control: holding and switching the dominant percept. During passive viewing, mean dominance duration in the older group was significantly longer (63%) than the dominance duration found in the young group. This age-related deficit could be due to a decline in the apparent strength of the alternating percepts as a result of higher contrast gain of visual cortical activity and a reduction in the amount of attentional resources allocated to the ambiguous stimulus in older people compared to young adults. In comparison to passive viewing, holding the dominant percept did not significantly alter the dominance durations in the older group, while the dominance durations in the young group were increased (∼100%). The dominance durations for both age groups in switch conditions were reduced compared to their passive viewing durations (∼40%). The inability of older people to voluntarily prolong the duration of the dominant percept suggests that they may have abnormal attentional mechanisms, which are inefficient at enhancing the effective strength of the dominant percept. Results suggest that older adults have difficulty holding attended visual objects in focus, a problem that could affect their ability to carry out everyday tasks

A Cross-Case Analysis of Disciplinary Identities Communicated Through Design Reviews

In post-secondary educational settings, discourse is a mechanism by which students develop occupational identities as they engage in a particular community that communicates attributes of their prospective profession. This study focuses on revealing disciplinary identities and how they are conveyed and negotiated during interactions between design students and project reviewers. We draw upon Gee’s identity framework and focus on the enactments of disciplinary identity in three different disciplinary settings: choreography, industrial design, and mechanical engineering. A cross-case analysis indicated differences that were epistemological (e.g., subjectivity of reviews) and similarities in ways instructors modeled institutional identities. The results have implications for interdisciplinary activities and suggest that disciplines that engage in design have much to learn from one another

Word-Based computer recognition of Printed text

Computer recognition of printed text luis been traditionally based on characters : each character is first extracted and then recognized by one of varions methods. Word recognition follows where contextual information is brought in (reference dictionary, confusion matrices, syntactic and semantic context, etc.) . Our approach is based directly on the recognition of the word ; no emphasis is put on the character or on context, although these can be used. A word is represented by simple and stable features computed directly from the word (length, position of ascenders, descenders, holes, etc .) . A word is recognized by matching its characteristics against those of a reference set, a hierarchically organized dictionary . A simple preferential process may be instantiated in the case of multiple matches. Experimental results have demonstrated not only the feasibility of the approach but also its advantages, simplicity, robusteness, and efficiency in an omnifont context .La reconnaissance de texte par ordinateur s'est traditionnellement faite à partir des caractères : on isole chacun des caractères d'un mot et, par une méthode de reconnaissance quelconque, on établit l'identité de chaque caractère . Une fois la reconnaissance de toutes les lettres d'un mot achevée, une analyse contextuelle est faite (dictionnaire, matrice de confusion, etc .) . Des approches « top-down » suggèrent que la reconnaissance d'un mot peut s'établir à partir du contexte de ce mot dans la phrase. Ce contexte peut être de nature diverse : statistique, syntaxique ou sémantique. Notre approche s'insère entre les deux approches mentionnées : on ne s'attardera ni aux caractères individuels constituant un mot, ni aux relations qui existent entre les mots d'une phrase . On s'intéressera au mot lui-même, à sa forme générale, à sa « signature graphique » . Cette signature graphique est établie à partir de caractéristiques très simples prélevées directement sur le mot (position dans le mot des ascendantes, descendantes, boucles, etc .) . Chaque mot d'un dictionnaire donné est classifié selon sa signature graphique : une classe sera donc constituée de mots dont la signature graphique est identique . Pour reconnaître un mot, il s'agit donc d'extraire les caractéristiques sur le mot, de trouver dans le dictionnaire la classe à laquelle il appartient, en extraire le (ou les) mots et d'y appliquer un traitement simple pour finaliser la reconnaissance du mot. Les résultats expérimentaux nous ont permis de démontrer que la reconnaissance de texte à partir des mots est non seulement réalisable mais qu'elle comporte des avantages : entre autres, sa grande simplicité et son efficacité dans les environnements omnifontes ainsi que son habilité à fonctionner dans les environnements bruités

Evapotranspiration in the Nile Basin: Identifying Dynamics, Trends, and Drivers 2002-2011

Analysis of the relationship between evapotranspiration (ET) and its natural and anthropogenic drivers is critical in water-limited basins such as the Nile. The spatiotemporal relationships of ET with rainfall and vegetation dynamics in the Nile Basin during 2002–2011 were analyzed using satellite-derived data. Non-parametric statistics were used to quantify ET-rainfall interactions and trends across land cover types and subbasins. We found that 65% of the study area (2.5 million km2) showed significant (p \u3c 0.05) positive correlations between monthly ET and rainfall, whereas 7% showed significant negative correlations. As expected, positive ET-rainfall correlations were observed over natural vegetation, mixed croplands/natural vegetation, and croplands, with a few subbasin-specific exceptions. In particular, irrigated croplands, wetlands and some forests exhibited negative correlations. Trend tests revealed spatial clusters of statistically significant trends in ET (6% of study area was negative; 12% positive), vegetation greenness (24% negative; 12% positive) and rainfall (11% negative; 1% positive) during 2002–2011. The Nile Delta, Ethiopian highlands and central Uganda regions showed decline in ET while central parts of Sudan, South Sudan, southwestern Ethiopia and northeastern Uganda showed increases. Except for a decline in ET in central Uganda, the detected changes in ET (both positive and negative) were not associated with corresponding changes in rainfall. Detected declines in ET in the Nile delta and Ethiopian highlands were found to be attributable to anthropogenic land degradation, while the ET decline in central Uganda is likely caused by rainfall reduction

Drought Monitoring and Assessment: Remote Sensing and Modeling Approaches for the Famine Early Warning Systems Network

Drought monitoring is an essential component of drought risk management. It is usually carried out using drought indices/indicators that are continuous functions of rainfall and other hydrometeorological variables. This chapter presents a few examples of how remote sensing and hydrologic modeling techniques are being used to generate a suite of drought monitoring indicators at dekadal (10-day), monthly, seasonal, and annual time scales for several selected regions around the world. Satellite-based rainfall estimates are being used to produce drought indicators such as standardized precipitation index, dryness indicators, and start of season analysis. The Normalized Difference Vegetation Index is being used to monitor vegetation condition. Several satellite data products are combined using agrohydrologic models to produce multiple short- and long-term indicators of droughts. All the data sets are being produced and updated in near-real time to provide information about the onset, progression, extent, and intensity of drought conditions. The data and products produced are available for download from the Famine Early Warning Systems Network (FEWS NET) data portal at http:// earlywarning.usgs.gov. The availability of timely information and products support the decision-making processes in drought-related hazard assessment, monitoring, and management with the FEWS NET. The drought-hazard monitoring approach perfected by the U.S. Geological Survey for FEWS NET through the integration of satellite data and hydrologic modeling can form the basis for similar decision support systems. Such systems can operationally produce reliable and useful regional information that is relevant for local, district-level decision making

Group problem management plus (PM+) to decrease psychological distress among Syrian refugees in Turkey: a pilot randomised controlled trial

BACKGROUND: Syrian refugees resettled in Turkey show a high prevalence of symptoms of mental disorders. Problem Management Plus (PM+) is an effective psychological intervention delivered by non-specialist health care providers which has shown to decrease psychological distress among people exposed to adversity. In this single-blind pilot randomised controlled trial, we examined the methodological trial procedures of Group PM+ (gPM+) among Syrian refugees with psychological distress in Istanbul, Turkey, and assessed feasibility, acceptability, perceived impact and the potential cost-effectiveness of the intervention. METHODS: Refugees with psychological distress (Kessler Psychological Distress Scale, K10 > 15) and impaired psychosocial functioning (World Health Organization Disability Assessment Schedule, WHODAS 2.0 > 16) were recruited from the community and randomised to either gPM+ and enhanced care as usual (E-CAU) (n = 24) or E-CAU only (n = 22). gPM+ comprised of five weekly group sessions with eight to ten participants per group. Acceptability and feasibility of the intervention were assessed through semi-structured interviews. The primary outcome at 3-month follow-up was symptoms of depression and anxiety (Hopkins Symptoms Checklist-25). Psychosocial functioning (WHODAS 2.0), symptoms of posttraumatic stress disorder and self-identified problems (Psychological Outcomes Profiles, PSYCHLOPS) were included as secondary outcomes. A modified version of the Client Service Receipt Inventory was used to document changes in the costs of health service utilisation as well as productivity losses. RESULTS: There were no barriers experienced in recruiting study participants and in randomising them into the respective study arms. Retention in gPM+ was high (75%). Qualitative analyses of the interviews with the participants showed that Syrian refugees had a positive view on the content, implementation and format of gPM+. No adverse events were reported during the implementation. The study was not powered to detect an effect. No significant difference between gPM+ and E-CAU group on primary and secondary outcome measures, or in economic impacts were found. CONCLUSIONS: gPM+ delivered by non-specialist peer providers seemed to be an acceptable, feasible and safe intervention for Syrian refugees in Turkey with elevated levels of psychological distress. This pilot RCT sets the stage for a fully powered RCT. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03567083 ; date: 25/06/2018

Development of a Benchmark Eddy Flux Evapotranspiration Dataset for Evaluation of Satellite-Driven Evapotranspiration Models Over the CONUS

A large sample of ground-based evapotranspiration (ET) measurements made in the United States, primarily from eddy covariance systems, were post-processed to produce a benchmark ET dataset. The dataset was produced primarily to support the intercomparison and evaluation of the OpenET satellite-based remote sensing ET (RSET) models and could also be used to evaluate ET data from other models and approaches. OpenET is a web-based service that makes field-delineated and pixel-level ET estimates from well-established RSET models readily available to water managers, agricultural producers, and the public. The benchmark dataset is composed of flux and meteorological data from a variety of providers covering native vegetation and agricultural settings. Flux footprint predictions were developed for each station and included static flux footprints developed based on average wind direction and speed, as well as dynamic hourly footprints that were generated with a physically based model of upwind source area. The two footprint prediction methods were rigorously compared to evaluate their relative spatial coverage. Data from all sources were post-processed in a consistent and reproducible manner including data handling, gap-filling, temporal aggregation, and energy balance closure correction. The resulting dataset included 243,048 daily and 5,284 monthly ET values from 194 stations, with all data falling between 1995 and 2021. We assessed average daily energy imbalance using 172 flux sites with a total of 193,021 days of data, finding that overall turbulent fluxes were understated by about 12% on average relative to available energy. Multiple linear regression analyses indicated that daily average latent energy flux may be typically understated slightly more than sensible heat flux. This dataset was developed to provide a consistent reference to support evaluation of RSET data being developed for a wide range of applications related to water accounting and water resources management at field to watershed scales

Spectroscopic Evidence for Interstellar Ice in Comet Hyakutake

Volatile compounds in comets are the most pristine materials surviving from the time of formation of the Solar System, and thus potentially provide information about conditions that prevailed in the primitive solar material. Moreover, comets may have supplied a substantial fraction of the volatiles on the terrestrial planets, perhaps including organic compounds that played a role in the origin of life on Earth. Here we report the detection of hydrogen isocyanide (HNC) in comet Hyakutake. The abundance of HNC relative to hydrogen cyanide (HCN) is very similar to that observed in quiescent interstellar molecular clouds, and quite different from the equilibrium ratio expected in the outermost solar nebula, where comets are thought to form. Such a departure from equilibrium has long been considered a hallmark of gas-phase chemical processing in the interstellar medium, suggesting that interstellar gases have been incorporated into the comet's nucleus, perhaps as ices frozen onto interstellar grains. If this interpretation is correct, our results should provide constraints on the temperature of the solar nebula, and the subsequent chemical processes that occurred in the region where comets formed