1,539 research outputs found

    Monitoring of oxygen condition in the Ria Formosa coastal lagoon, Portugal

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    Dissolved oxygen (DO) is one of the most important environmental variables of water quality, especially for marine life. Consequently, oxygen is one of the Chemical Quality Elements required for the implementation of European Union Water Framework Directive. This study uses the example of the Ria Formosa, a meso-tidal lagoon on the south coast of Portugal to demonstrate how monitoring of water quality for coastal waters must be well designed to identify symptoms of episodic hypoxia. New data from the western end of the Ria Formosa were compared to values in a database of historical data and in the published literature to identify long-term trends. The dissolved oxygen concentration values in the database and in the literature were generally higher than those found in this study, where episodic hypoxia was observed during the summer. Analysis of the database showed that the discrepancy was probably related with the time and the sites where the samples had been collected, rather than a long-term trend. The most problematic situations were within the inner lagoon near the city of Faro, where episodic hypoxia (<2 mg dm3 DO) occurred regularly in the early morning. These results emphasise the need for a balanced sampling strategy for oxygen monitoring which includes all periods of the day and night, as well as a representative range of sites throughout the lagoon. Such a strategy would provide adequate data to apply management measures to reduce the risk of more persistent hypoxia that would impact on the ecological, important natural resource. economic and leisure uses of this Important natural resource

    On the physics and technology of gaseous particle detectors

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    Despite an already long and fruitful history, gaseous elementary-particle detectors remain today an important mainstay of high-energy and nuclear physics experiments and of radiation detection in general. In here we briefly describe some of the gaseous detector's main technologies and applications, along with some unsolved gas-discharge physics aspects of practical relevance.Comment: Submitted to Plasma Sources in Science and Technolog

    Morphology And Behavior Of The Early Stages Of The Skipper, Urbanus Esmeraldus, On Urera Baccifera, An Ant-visited Host Plant.

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    The Neotropical genus Urbanus (Hübner) (Lepidoptera: Hesperiidae) contains around 34 described species, and is widely distributed from the extreme southern United States to Argentina. Here, we describe the larval morphology and behavior of Urbanus esmeraldus (Hübner)(Hesperiidae) in Urera baccifera (Urticaceae), a plant producing food rewards and fleshy fruits that attract ants (including predacious species) in a Brazilian forest. Larvae pass through five instars and construct two kinds of leaf shelters. Experiments with ejected fecal pellets showed that these can serve as cues to ground-dwelling ants that climb onto host plants and potentially attack the larvae. Manipulation with pellets placed at different distances suggests that ejection behavior decreases larval vulnerability to ant predation. Larval preference for mature leaves may be related with increased predation risk at ant-visited young leaves. The study shows that a combination of natural history and experimental data can help understand the life history of a butterfly using a plant with high predation risk.125

    A runtime lifecycle for interactive public display applications

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    —Public display systems are becoming increasingly complex. They are moving from passive closed systems to open interactive systems that are able to accommodate applications from several independent sources. This shift needs to be accompanied by more flexible and powerful application management. In this paper, we propose a runtime lifecycle model for interactive public display applications that addresses several shortcomings of current display systems. Our model allows applications to load their resources before they are displayed, enables the system to quickly pause and resume applications, provides strategies for applications to terminate gracefully by requesting additional time to finish the presentation of content, allows applications to save their state before being destroyed and gives applications the opportunity to request and relinquish display timeinfo:eu-repo/semantics/publishedVersio

    Novel diagnostic tools for Asian (Apis cerana) and European (Apis mellifera) honey authentication

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    Honey can be produced by different species of honeybees, with two being of economic importance due to their use in apiculture, namely Apis mellifera (known as European honeybee) and Apis cerana (known as Asian honeybee). Due to the decline of the wild populations of the Asian honeybee, this honey generally attains much higher market value, being prone to adulteration. This work aims at proposing new tools, based on the use of molecular markers, for the entomological authentication of honey. To this end, new species-specific primers were designed targeting the tRNA leu -cox2 intergenic region and allowing the detection of A. cerana DNA by qualitative polymerase chain reaction (PCR). Additionally, a novel real-time PCR method with high resolution melting analysis was developed to target the 16S rRNA gene of both bee species, allowing their discrimination in different clusters. The proposed methodologies were further applied with success in the authentication of Asian and European honey samples by the identification of honeybee DNA, demonstrating the usefulness of these simple and cost-effective new approaches.We thank Matt Webster from Uppsala University for providing the A. cerana samples from China and Thailand. This work was supported by FCT (Fundação para a Ciência e Tecnologia) through project UID/QUI/50006/2013 – POCI/01/0145/FEDER/007265 with financial support from FCT/MEC through national funds and co-financed by FEDER, under the Partnership Agreement PT2020 and by the project NORTE-01-0145-FEDER-000011. S. Soares and J. Costa are grateful to FCT grants (SFRH/BD/75091/2010 and SFRH/BPD/102404/2014, respectively) financed by POPH-QREN (subsidised by FSE and MCTES).info:eu-repo/semantics/publishedVersio

    How additive manufacturing can boost the bioactivity of baked functional foods

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    The antioxidant activity of baked foods is of utmost interest when envisioning enhancing their health benefits. Incorporating functional ingredients is challenging since their bioactivity naturally declines during baking. In this study, 3D food printing and design of experiments are employed to clarify how the antioxidant activity of cookies enriched with encapsulated polyphenols can be maximized. A synergistic effect between encapsulation, time, temperature, number of layers, and infill of the printed cookies was observed on the moisture and antioxidant activity. Four-layer cookies with 30% infill provided the highest bioactivity and phenolic content if baked for 10 min and at 180 °C. The bioacitivity and total phenolic content improved by 115% and 173%, respectively, comparing to free extract cookies.Moreover, the proper combination of the design and baking variables allowed to vary the bioactivity of cooked cookies (moisture 35%) between 300 and 700 ?molTR/gdry. The additive manufacture of foods with interconnected pores could accelerate baking and browning, or reduce thermal degradation. This represents a potential approach to enhance the functional and healthy properties of cookies or other thermal treated bioactive food products.The research leading to these results has received funding from FODIAC – Food for Diabetes and Cognition, funded by European Union, under the call Marie Skłodowsk-Curie Research and Innovation Staff Exchange (Ref. H2020-MSCA-RISE-778388); PhD grantship from Fondazione di Piacenza e Vigevano (Doctoral School on the Agro-Food System, Università Cattolica del Sacro Cuore); Fondazione Cariplo through the project ReMarcForFood – Biotechnological strategies for the conversion of Winemaking by-products and their recycling into the food chain: development of new concepts of use, 2016-0740 grant.info:eu-repo/semantics/publishedVersio

    Integrating Science, Technology, Engineering and Mathematics contents through PBL in an Industrial Engineering and Management first year program

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    Paper aims: This paper presents teachers and students perspectives of integration Science, Technology, Engineering and Mathematics (STEM) courses contents into the first year of Industrial Engineering and Management (IEM) program through Project-Based Learning (PBL). Originality: These perspectives provide strategies that IEM teachers could use to challenge students to apply STEM contents to design a product and its production system by developing a semester interdisciplinary project. Research method: Grounded on project deliveries and an on-line questionnaire, the teachers and students' work and perceptions were analysed in order to understand and to evaluate the effectiveness of such strategies. Main findings: Results pointed out a general satisfaction of the teachers with the way teams integrate the STEM contents to design the production system and the product and students proud of their projects. Implications for theory and practice: PBL is recognized as an active learning methodology that engages students in their own learning process and allows them to realize the relevance of all courses and the role of each to design a product/production system. Nevertheless, is fundamental a good knowledge of the PBL process to achieve this.This work has been supported by FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/201

    A mild and efficient method for the preparation of 3-(2'-Aminoaryl)pyrazoles from 4-chloroquinolines

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    We describe a mild and efficient method for the formation of 3-(2'-aminoaryl)pyrazoles in excellent yields from reactions of 4-chloroquinolines with hydrazine. These heterocyclic ring opening reactions occur under much milder conditions then previously described

    2,4,5-Triaminopyrimidines as blue fluorescent probes for cell viability monitoring: synthesis, photophysical properties, and microscopy applications

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    Monitoring cell viability is critical in cell biology, pathology, and drug discovery. Most cell viability assays are cell-destructive, time-consuming, expensive, and/or hazardous. Herein, we present a series of newly synthesized 2,4,5-triaminopyrimidine derivatives able to discriminate between live and dead cells. To our knowledge, these compounds are the first fluorescent nucleobase analogues (FNAs) with cell viability monitoring potential. These new fluorescent molecules are synthesized using highly efficient and cost- effective methods and feature unprecedented photophysical properties (longer absorption and emission wavelengths, environment-sensitive emission, and unprecedented brightness within FNAs). Using a live– dead Saccharomyces cerevisiae cell and theoretical assays, the fluorescent 2,4,5-triaminopyrimidine derivatives were found to specifically accumulate inside dead cells by interacting with dsDNA grooves, thus paving the way for the emergence of novel and safe fluorescent cell viability markers emitting in the blue region. As the majority of commercially available viability dyes emit in the green to red region of the visible spectrum, these novel markers might be useful to meet the needs of blue markers for co-staining combinations
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