426 research outputs found
A Belief System's Organization Based on a Computational Model of the Dynamic Context: First Approximation
In this article we present a model of organization of a belief system based on a set of binary recursive functions that characterize the dynamic context that modifies the beliefs. The initial beliefs are modeled by a set of two-bit words that grow, update, and generate other beliefs as the different experiences of the dynamic context appear. Reason is presented as an emergent effect of the experience on the beliefs. The system presents a layered structure that allows a functional organization of the belief system. Our approach seems suitable to model different ways of thinking and to apply to different realistic scenarios such as ideologies
Optical types of inland and coastal waters
Inland and coastal waterbodies are critical components of the global biosphere. Timely monitoring is necessary to enhance our understanding of their functions, the drivers impacting on these functions and to deliver more effective management. The ability to observe waterbodies from space has led to Earth observation (EO) becoming established as an important source of information on water quality and ecosystem condition. However, progress toward a globally valid EO approach is still largely hampered by inconsistences over temporally and spatially variable in‐water optical conditions. In this study, a comprehensive dataset from more than 250 aquatic systems, representing a wide range of conditions, was analyzed in order to develop a typology of optical water types (OWTs) for inland and coastal waters. We introduce a novel approach for clustering in situ hyperspectral water reflectance measurements (n = 4045) from multiple sources based on a functional data analysis. The resulting classification algorithm identified 13 spectrally distinct clusters of measurements in inland waters, and a further nine clusters from the marine environment. The distinction and characterization of OWTs was supported by the availability of a wide range of coincident data on biogeochemical and inherent optical properties from inland waters. Phylogenetic trees based on the shapes of cluster means were constructed to identify similarities among the derived clusters with respect to spectral diversity. This typification provides a valuable framework for a globally applicable EO scheme and the design of future EO missions
The behaviour of repeat visitors to museums: Review and empirical findings
This study presents a theoretical and operational framework for analysing repeat visit to museums. Starting from the literature on repeat visit in tourism, the specificities of these cultural attractions are made explicit through a review of theoretical and applied works. Consistently with previous contributors, the paper suggests that the analysis of actual past behaviours has to be preferred to the one of attitudes. The application of proper econometric models is also remarked in order to put into account individual profiles. Information coming from three techniques is then used in an integrated way in order to provide a more comprehensive view of the phenomenon. Evidence from an ad hoc survey suggests the necessity to give a greater attention to perceived cultural value during the visit, promoting cultural events during the week and addressed to children, and taking care of those visitors that come from far places also through an integrated tourist supply. © 2013 Springer Science+Business Media Dordrecht
Remote Estimation of Net Ecosystem CO2 Exchange in Crops: Principles, Technique Calibration and Validation
Accurate and synoptic estimation of spatially distributed CO2 fluxes is of great importance for regional and global studies of carbon balance. A technique solely based on remotely sensed data was developed and tested for estimating net ecosystem CO2 exchange (NEE) in maize and soybean. The model is based on the reflectance in two spectral channels: the near-infrared and either the green or red-edge around 700 nm. The technique provides accurate estimations of mid-day NEE in both crops under either rainfed or irrigated conditions, explaining more than 85% of NEE variation in maize and more than 81% in soybean, and shows great potential for remotely tracking crop NEE
Response and resilience of Spartina alterniflora to sudden dieback
We measured an array of biophysical and spectral variables to evaluate the response and recovery of Spartina alterniflora to a sudden dieback event in spring and summer 2004 within a low marsh in coastal Virginia, USA. S. alterniflora is a foundation species, whose loss decreases ecosystem services and potentiates ecosystem state change. Long-term records of the potential environmental drivers of dieback such as precipitation and tidal inundation did not evidence any particular anomalies, although Hurricane Isabel in fall 2003 may have been related to dieback. Transects were established across the interface between the dieback area and apparently healthy areas of marsh. Plant condition was classified based on ground cover within transects as dieback, intermediate and healthy. Numerous characteristics of S. alterniflora culms within each condition class were assessed including biomass, morphology and spectral attributes associated with photosynthetic pigments. Plants demonstrated evidence of stress in 2004 and 2005 beyond areas of obvious dieback and resilience at a multi-year scale. Resilience of the plants was evident in recovery of ground cover and biomass largely within 3 y, although a small remnant of dieback persisted for 8 y. Culms surviving within the dieback and areas of intermediate impact had modified morphological traits and spectral response that reflected stress. These morphometric and spectral differences among plant cover condition classes serve as guidelines for monitoring of dieback initiation, effects and subsequent recovery. Although a number of environmental and biotic parameters were assessed relative to causation, the reason for this particular dieback remains largely unknown, however
Non-Destructive Optical Monitoring of Grape Maturation by Proximal Sensing
A new, commercial, fluorescence-based optical sensor for plant constituent assessment was recently introduced. This sensor, called the Multiplex® (FORCE-A, Orsay, France), was used to monitor grape maturation by specifically monitoring anthocyanin accumulation. We derived the empirical anthocyanin content calibration curves for Champagne red grape cultivars, and we also propose a general model for the influence of the proportion of red berries, skin anthocyanin content and berry size on Multiplex® indices. The Multiplex® was used on both berry samples in the laboratory and on intact clusters in the vineyard. We found that the inverted and log-transformed far-red fluorescence signal called the FERARI index, although sensitive to sample size and distance, is potentially the most widely applicable. The more robust indices, based on chlorophyll fluorescence excitation ratios, showed three ranges of dependence on anthocyanin content. We found that up to 0.16 mg cm−2, equivalent to approximately 0.6 mg g−1, all indices increase with accumulation of skin anthocyanin content. Excitation ratio-based indices decrease with anthocyanin accumulation beyond 0.27 mg cm−2. We showed that the Multiplex® can be advantageously used in vineyards on intact clusters for the non-destructive assessment of anthocyanin content of vine blocks and can now be tested on other fruits and vegetables based on the same model
Роль сугаммадекса при эндоваскулярных вмешательствах на сосудах головного мозга
Highlights. The article discusses the features of general anesthesia in patients with cerebrovascular diseases using the relaxant binding agent sugammadex.Aim. To evaluate the effectiveness of sugammadex in endovascular management of cerebrovascular diseases.Methods. The study included 57 patients who underwent endovascular treatment of cerebrovascular disease under general anesthesia. The experimental group included 29 patients who were injected with sugammadex - a selective relaxant binding agent for reversal of neuromuscular block induced by rocuronium. The comparison group included 28 patients who did not undergo decurarization (n = 13), or it was performed with neostigmine (n = 15). Acceleromyography was used to monitor the state of neuromuscular function.Result. Onset of action and duration of action of rocuronium at a dose of 0.9 mg/kg did not differ between the groups. The neuromuscular recovery time was 2.14 [1.67; 2.59] minutes after administration of sugammadex, compared with spontaneous 35.8 [31.5; 40.4] minutes and neostigmine-induced 22.1 [16.8; 27.3] minutes (p<0.001). No adverse or allergic reactions were noted after administration of the relaxant binding agent.Conclusion. Using a specific antidote sugammadex to eliminate the effect of rocuronium helps to restore neuromuscular function within 2–3 minutes and assess the neurological status of patients immediately after the endovascular treatment of cerebrovascular disease.Основные положения. В статье обсуждаются особенности проведения общей анестезии пациентам с сосудистыми заболеваниями головного мозга с использованием релаксант-связывающего агента сугаммадекса.Цель. Оценка эффективности сугаммадекса при эндоваскулярных вмешательствах на сосудах головного мозга.Материалы и методы. В исследование включены 57 пациентов, которым выполнено рентгенэндоваскулярное вмешательство на сосудах головного мозга в условиях общей анестезии. В исследуемую группу вошли 29 больных, которым вводили сугаммадекс – релаксант-связывающий агент рокурония. Группу сравнения составили 28 пациентов, которым декураризация не выполнена (n = 13) или проведена с помощью неостигмина (n = 15). Для контроля состояния нейромышечной функции использован метод акcелерометрического мониторинга.Результаты. Время начала действия и клиническая продолжительность действия рокурония в дозе 0,9 мг/кг не различались в группах. Время восстановления нейромышечной проводимости после введения сугаммадекса составило 2,14 [1,67; 2,59] мин в сравнении с 35,8 [31,5; 40,4] мин при спонтанном восстановлении и 22,1 [16,8; 27,3] мин при восстановлении, индуцированным неостигмином (p<0,001). Не зафиксировано каких-либо побочных и аллергических реакций после введения релаксант-связывающего агента.Заключение. Использование специфического антидота сугаммадекса для устранения эффекта рокурония позволяет в течение 2–3 мин полностью восстановить нейромышечное проведение и оценить неврологический статус пациентов сразу после окончания эндоваскулярного вмешательства на сосудах головного мозга
GLORIA - A globally representative hyperspectral in situ dataset for optical sensing of water quality
The development of algorithms for remote sensing of water quality (RSWQ) requires a large amount of in situ data to account for the bio-geo-optical diversity of inland and coastal waters. The GLObal Reflectance community dataset for Imaging and optical sensing of Aquatic environments (GLORIA) includes 7,572 curated hyperspectral remote sensing reflectance measurements at 1 nm intervals within the 350 to 900 nm wavelength range. In addition, at least one co-located water quality measurement of chlorophyll a, total suspended solids, absorption by dissolved substances, and Secchi depth, is provided. The data were contributed by researchers affiliated with 59 institutions worldwide and come from 450 different water bodies, making GLORIA the de-facto state of knowledge of in situ coastal and inland aquatic optical diversity. Each measurement is documented with comprehensive methodological details, allowing users to evaluate fitness-for-purpose, and providing a reference for practitioners planning similar measurements. We provide open and free access to this dataset with the goal of enabling scientific and technological advancement towards operational regional and global RSWQ monitoring
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