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941.
Debora Puglia Franco Dominici José Maria Kenny Carlo Santulli Catia Governatori Giacomo Tosti Paolo Benincasa 《Journal of Polymers and the Environment》2016,24(1):37-47
The production of bioplastics directly from wheat flour has been demonstrated to be reliable, but scarce knowledge is available on how flour characteristics may affect the performance of thermoplastic films. In this work, we first established the most suitable recipe and process for the production of extruded films and then we used eight single-cultivar wheat flours with different baking technological properties to assess how they affect the mechanical properties of thermoplastic films. The results have shown that flours from soft grain cultivars offered more rigid and deformable films than flours from hard grain cultivars. For similar hardness, the alveographic P/L ratio of the dough was inversely related to rigidity and directly related to deformability of plastic films, while the deformation energy of the dough (W) played a role only for great differences of it. The subsequent fabrication of blends between each of the flours that yielded the best film properties and polycaprolactone (PCL) at different proportions indicated that a wheat flour/PCL ratio (TWF/PCL) of 75/25 offered the most suitable films for further application. Our results are likely to be useful for improving the plasticization of flour, in that selection of wheat flours could be tailored on the properties desired for the bioplastic films. 相似文献
942.
Alicia Pelegrina-López Francisco M. Ocaña-Peinado Ignacio Henares-Civantos José L. Rosúa-Campos 《Journal of Environmental Planning and Management》2018,61(1):124-142
Protected areas cannot be considered as elements isolated from the human groups that inhabit them. Consideration of the social factor is fundamental to guarantee the success of any management model. In this sense, analyzing the perception of people who live in protected areas can be a key tool for the formulation of proposals for improving the existing models. This article explores perceptions of local residents in the Sierra Nevada Protected Area in Southern Spain and identifies the socio-demographic factors that affect these perceptions. The main objective is to generate relevant data for the protected area management team. The recommendations we can offer entail a review of the communication plan and participatory strategy considering social differences in perceptions of the local population. 相似文献
943.
Rocío Pérez-Campaña Luis Miguel Valenzuela-Montes 《Journal of Environmental Planning and Management》2018,61(3):406-429
The ecological value of some fine-scale landscape elements tends to be overlooked when they are found in highly human-influenced landscapes, such as peri-urban agricultural ones. These landscapes usually fall beyond the scope of the defined categories of landscape protection, and are thus mapped as areas of little or no ecological interest in the context of extensive analysis. In this paper, we present a method for assessing and visualizing the existing nodes in the field pattern of a peri-urban agricultural landscape. Nodes are identified from the field pattern and characterized according to the presence of relevant features and land uses from the viewpoint of their ecological functions. The method is applied in the Vega del Guadalfeo (south of Spain). Our results show an innovative map of the Vega which may be interpreted as its eco-structure; a model based on nodes to represent the ecological value of the peri-urban agricultural landscape. 相似文献
944.
945.
Koengkan Matheus Fuinhas José Alberto Silva Nuno 《Environmental science and pollution research international》2021,28(2):1656-1674
Environmental Science and Pollution Research - The impact of renewable energy consumption on reducing the outdoor air pollution death rate, in nineteen Latin America & the Caribbean... 相似文献
946.
Frédéric Soulignac Brigitte Vinçon-Leite Bruno J. Lemaire José R. Scarati Martins Céline Bonhomme Philippe Dubois Yacine Mezemate Ioulia Tchiguirinskaia Daniel Schertzer Bruno Tassin 《Environmental Modeling and Assessment》2017,22(4):309-322
Urban lakes provide many ecosystem services, e.g., flood control, nature protection, coolness island, recreation. Hydrodynamic models will increasingly be used to enhance these benefits. We present the first validation of a three-dimensional (3D) hydrodynamic model on a small shallow lake with high resolution and high frequency measurements. Lake Créteil, France (area 0.4 km2, mean depth 4.5 m, and catchment area 1 km2) is a former gravel pit and now part of a regional park. The model Delft3D-FLOW was calibrated on a one-month period, with continuous measurements of temperature at five depths at the center of the lake and at three depths at two other stations, and with current speed profiles at the centre of the lake. The model was then verified on 18 1-month periods with similar temperature measurements. The model reproduced very well the temperature dynamics, including the alternation between mixing and stratification periods and internal wave patterns. The mean absolute errors over the five depths at the central point remained below 0.55°C in spring and summer, the most favorable seasons for phytoplankton growth. Horizontal temperature differences, which rose up to 3°C at the beginning of stratification periods, were also well reproduced, as well as current speeds. These results are very promising for assessing nutrient and pollutant diffusion, settling and resuspension, as well as for understanding how phytoplankton blooms start in small shallow lakes. 相似文献
947.
948.
The role of automated feedback in training and retaining biological recorders for citizen science
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René van der Wal Nirwan Sharma Chris Mellish Annie Robinson Advaith Siddharthan 《Conservation biology》2016,30(3):550-561
The rapid rise of citizen science, with lay people forming often extensive biodiversity sensor networks, is seen as a solution to the mismatch between data demand and supply while simultaneously engaging citizens with environmental topics. However, citizen science recording schemes require careful consideration of how to motivate, train, and retain volunteers. We evaluated a novel computing science framework that allowed for the automated generation of feedback to citizen scientists using natural language generation (NLG) technology. We worked with a photo‐based citizen science program in which users also volunteer species identification aided by an online key. Feedback is provided after photo (and identification) submission and is aimed to improve volunteer species identification skills and to enhance volunteer experience and retention. To assess the utility of NLG feedback, we conducted two experiments with novices to assess short‐term (single session) and longer‐term (5 sessions in 2 months) learning, respectively. Participants identified a specimen in a series of photos. One group received only the correct answer after each identification, and the other group received the correct answer and NLG feedback explaining reasons for misidentification and highlighting key features that facilitate correct identification. We then developed an identification training tool with NLG feedback as part of the citizen science program BeeWatch and analyzed learning by users. Finally, we implemented NLG feedback in the live program and evaluated this by randomly allocating all BeeWatch users to treatment groups that received different types of feedback upon identification submission. After 6 months separate surveys were sent out to assess whether views on the citizen science program and its feedback differed among the groups. Identification accuracy and retention of novices were higher for those who received automated feedback than for those who received only confirmation of the correct identification without explanation. The value of NLG feedback in the live program, captured through questionnaires and evaluation of the online photo‐based training tool, likewise showed that the automated generation of informative feedback fostered learning and volunteer engagement and thus paves the way for productive and long‐lived citizen science projects. 相似文献
949.
José Santana Clara Giraudi Emílio Marengo Elisa Robotti Sara Pires Inês Nunes Elvira M. Gaspar 《Environmental science and pollution research international》2014,21(2):1380-1390
This paper reports, for the first time, the concentrations of selected phthalates in drinking water consumed in Portugal. The use of bottled water in Portugal has increased in recent years. The main material for bottles is polyethylene terephthalate (PET). Its plasticizer components can contaminate water by leaching, and several scientific studies have evidenced potential health risks of phthalates to humans of all ages. With water being one of the most essential elements to human health and because it is consumed by ingestion, the evaluation of drinking water quality, with respect to phthalate contents, is important. This study tested seven commercial brands of bottled water consumed in Portugal, six PET and one glass (the most consumed) bottled water. Furthermore, tap water from Lisbon and three small neighbor cities was analyzed. Phthalates (di-n-butyl phthalate ester (DnBP), bis(2-ethylhexyl) phthalate ester (DEHP), and di-i-butyl phthalate ester (DIBP)) in water samples were quantified (PET and glass) by means of direct immersion solid-phase microextraction and ionic liquid gas chromatography associated with flame ionization detection or mass spectrometry due to their high boiling points and water solubility. The method utilized in this study showed a linear range for target phthalates between 0.02 and 6.5 μg L?1, good precision and low limits of detection that were between 0.01 and 0.06 μg L?1, and quantitation between 0.04 and 0.19 μg L?1. Only three phthalates were detected in Portuguese drinking waters: dibutyl (DnBP), diisobutyl (DIBP), and di(ethylhexyl) phthalate (DEHP). Concentrations ranged between 0.06 and 6.5 μg L?1 for DnBP, between 0.02 and 0.16 μg L?1 for DEHP, and between 0.1 and 1.89 μg L?1 for DIBP. The concentration of DEHP was found to be up to five times higher in PET than in glass bottled water. Surprisingly, all the three phthalates were detected in glass bottled water with the amount of DnBP being higher (6.5 μg L?1) than in PET bottled water. These concentrations do not represent direct risk to human health. Regarding potable tap water, only DIBP and DEHP were detected. Two of the cities showed concentration of all three phthalates in their water below the limits of detection of the method. All the samples showed phthalate concentrations below 6 μg L?1, the maximum admissible concentration in water established by the US Environmental Protection Agency. The concentrations measured in Portuguese bottled waters do not represent any risk for adult's health. 相似文献
950.
The present study represents the first comprehensive work dealing with the dietary analysis of Caprellidea. We studied 743
specimens of 31 genera and 62 species from all around the world. Analysis of digestive contents revealed that caprellids are
mainly detritivores (detritus represented the 86% of the caprellid diet), but a small percentage of species, those lacking
molars belonging to the Phtisicinae, can be considered as obligate predators and feed mainly on small crustaceans (copepods
and other amphipods) and polychaetes. The contribution of sponges, hydroids, macroalgae, diatoms and dinoflagellates to the
caprellid diet was very low (<2%). Apart from the clear relationship between the absence of molar process and predators, no
other correlations between digestive contents and mouthpart structure were found. Cluster analysis based on the dietary data
indicated a patent segregation between the Phtisicinae (obligate predators) and Caprellinae (detritivores, detritivores/predators
or opportunistics) and could support the hypothesis of basal divergence in two major lines of evolution: Phtisicinae and Caprogammaridae–Caprellinae.
Consequently, the debate questioning if the taxon Caprellidea is a monophyletic group or not is still open. Additional morphological,
molecular and behavioral studies are necessary to define the evolutionary relationships in this group of crustaceans. 相似文献