During pesticide application, operators are exposed to chemical products. Dermal exposure has been reported as the principal means of exposure for growers. In the present work, potential dermal ...exposure (PDE) has been assessed when using new low-cost equipment (a knapsack with a vertical spray boom) and compared to a hand-held spray lance, which is the equipment most widely used by growers in greenhouses. Two sprayers were used, a hand-held spray lance with four twin flat-fan nozzles and a knapsack fitted out with a vertical spray boom containing 3 pairs of twin flat-fan nozzles. Three applications were carried out and compared, one with the spray lance walking backwards (the reference application), and two with the spray boom - the first stopping at the turns and the second with no stopping. The patch method (19 position on the body) and tartrazine (the tracer) were used to assess de PDE. Each application tested was replicated three times. The results show that the knapsack with the vertical boom should not be used walking continuously along the greenhouse rows because the total PDE (1637.12mL 1000L−1) is greater than in the rest of the configurations tested. If the operator stops at the turns for a few seconds, allowing the previously sprayed droplet cloud to dissipate, the level of exposure decreases significantly (324.63mL 1000L−1), providing similar results to the reference application with the spray lance walking backwards (292.25mL 1000L−1).
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•Greenhouse operators have high exposure rates when using hand-held sprayers.•Path method and tartrazine have been used to assess the PDE.•PDE has been assessed with spray lance in comparison to new low-cost equipment.•The knapsack (stopping) gives PDE values similar to the lance walking backwards.
The use of PEG‐based hydrogels as cell culture matrix to mimic the natural extracellular matrix (ECM) has been realized using a range of well‐defined, tunable, and dynamic scaffolds, although they ...require cell adhesion ligands such as RGDS‐peptide (Arg‐Gly‐Asp‐Ser) to promote cell adhesion. Herein the synthesis of ionic and degradable hydrogels is demonstrated for cell culture by crosslinking PEG‐SH4 with the zwitterionic crosslinker N,N‐bis(acryloxyethyl)‐N‐methyl‐N‐(3‐sulfopropyl) ammonium betaine (BMSAB) and the cationic crosslinker N,N‐bis(acryloxyethyl)‐N,N‐dimethyl‐1‐ammonium iodide (BDMAI). Depending on the amount of ionic crosslinker used in gel formation, the hydrogels show tunable gelation time and stiffness. At the same time, the ionic groups act as catalysts for hydrolytic degradation, thereby allowing to define a stability window. The latter could be tailored in a straightforward manner by introducing the non‐degradable crosslinker tri(ethylene glycol) divinyl ether. In addition, both ionic crosslinkers favor cell attachment in comparison to the pristine PEG hydrogels. The degradation is examined by swelling behavior, rheology, and fluorescence correlation spectroscopy indicating degradation kinetics depending on diffusion of incorporated fluorescent molecules.
They herein demonstrate the synthesis and time‐dependent stability of PEG‐based hydrogels with tunable stiffness. The incorporation of degradable and charged crosslinkers allows to introduce cell adhesion ligands such as RGDS peptides and favors cell adhesion.
The study of vulnerable road users (VRUs) behavior is key to designing and optimizing driving assistance systems, such as the autonomous emergency braking (AEB) system. These kinds of devices could ...help lower the VRU accident rate, which is of particular interest to cyclists, who are the subject of this research. To better understand cyclists’ reaction patterns in frequently occurring collision scenarios in urban environments, this paper focuses on developing a virtual reality (VR) simulator for cyclists (VRBikeSim) that incorporates eye-tracking functionality. The braking and steering systems were calibrated by means of on-track tests with a sensorized bicycle in order to improve the accuracy of the bicycle virtual model. From the data obtained in the virtual tests, a battery of predictive models was built using supervised machine learning classifiers. All of them exhibited an accuracy higher than 85%, especially the K-Nearest Neighbors model. This model allowed us to obtain the best balance between the prediction of avoidance and collision cases, as well as enabling computationally lower times to be incorporated into the decision-making algorithm of an AEB system.
The disposable bronchoscope is an excellent alternative to face the problem of SARS-CoV-2 and other cross infections, but the bronchoscopist's perception of its quality has not been evaluated.
To ...evaluate the quality of the Ambu-aScope4 disposable bronchoscope, we carried out a cross-sectional study in 21 Spanish pulmonology services. We use a standardized questionnaire completed by the bronchoscopists at the end of each bronchoscopy. The variables were described with absolute and relative frequencies, measures of central tendency and dispersion depending on their nature. The existence of learning curves was evaluated by CUSUM analysis.
The most frequent indications in 300 included bronchoscopies was bronchial aspiration in 69.3% and the median duration of these was 9.1 min. The route of entry was nasal in 47.2% and oral in 34.1%. The average score for ease of use, image, and aspiration quality was 80/100. All the planned techniques were performed in 94.9% and the bronchoscopist was satisfied in 96.6% of the bronchoscopies. They highlighted the portability and immediacy of the aScope4TM to start the procedure in 99.3%, the possibility of taking and storing images in 99.3%. The CUSUM analysis showed average scores > 70/100 from the first procedure and from the 9th procedure more than 80% of the scores exceeded the 80/100 score.
The aScope4™ scored well for ease of use, imaging, and aspiration. We found a learning curve with excellent scores from the 9th procedure. Bronchoscopists highlighted its portability, immediacy of use and the possibility of taking and storing images.
The National Assembly of Ecuador repealed the Environmental Tax on Vehicle Pollution, which taxed the engine displacement of vehicles. This article aims to make an estimate of the energy savings that ...would have been achieved if this tax had been maintained and executed as originally planned. A methodology was applied to forecast energy consumption, using the Long-range Energy Alternative Planning software, with which two scenarios were analyzed. In the first one, it was considered that new vehicles would be acquired, with the same behavior a buyer would have had from 2012 to 2019, when this tax was a current law. The second scenario, without this imposition, considered that new vehicles would be acquired according to the demand pattern between 2008 and 2011, the period prior to this demand. From the analysis of each scenario, it was concluded that by 2025, there would have been an approximate reduction of 29,200,000 gal of gasoline eq. that represents a saving of 5% in the respective energy consumption, as well as a lower emission of carbon dioxide. A tax on the engine displacement of the vehicle discourages the purchase of unnecessarily large vehicles, which implies a lower consumption of petroleum derivatives and a lower emission of greenhouse gases.
•The green tax in Ecuador could have reduced light transport energy consumption by 5%.•A cylinder displacement tax discourages the purchase of unnecessarily large vehicles.•The green tax in Ecuador can be a tool to achieve climate change commitments.•A cylinder displacement tax may decrease imports of derivatives.
The cultivation of vegetables in greenhouses is characterised by high planting density and environmental conditions that favour the development of pests and diseases. These are mainly controlled ...using plant protection products applied with a hand-held sprayer. This is inefficient low-tech equipment that is difficult to calibrate. The study evaluates one hand-held spray gun and two hand-held spray lances that are widely used in greenhouse vegetable crops. The tests were carried out on a pepper crop at two different developmental stages. Plant canopy deposition and losses to the ground were quantified using a colorimetric method based on applying a tartrazine solution. The results show that the flat-fan spray lance obtains a more uniform spray distribution in the plant canopy and results in losses to the ground that are between 2 and 2.75 times less than when using the other hand-held sprayers tested.
In Latin America and the Caribbean, the interrelationships among water, energy, and food are complex, partly due to their development models, which are intensive in their use of these resources. This ...research aims to recognize and quantify the use of water and energy in food in Ecuador by identifying the main interrelationships, together with their causes and current impacts. Regarding methodology, this research uses sectoral data available at the national level and international databases to obtain cross indexes. The following indicators were sought: percentage of energy demanded by food in different stages, extraction of water for agricultural use, food energy productivity, virtual water, and embodied energy. As a result, it was estimated that food consumes 50% of imported energy and cocoa stands out with 7.6 km3 of water footprint; the products with the highest energy consumption are shrimp with 2090 KBOE and fish with 1459 KBOE. Fishing and aquaculture products present with a significantly high consumption level. Nearly all the virtual water and embodied energy are exported in banana, cocoa, and shrimp. Exporting groups make extensive use of the country’s water and energy resources.
Grey mould caused by Botrytis cinerea is an endemic disease in greenhouse tomato crops in the Mediterranean Basin, where the scarcity of heating systems together with the winter weather conditions ...makes the use of fungicides necessary. The availability of fungicides for organic tomato production is limited, and traditionally, farmers have used copper-based formulations. In the present work, in vitro tests with twelve commercial formulations resulted in cinnamon extract and potassium hydrogen carbonate (PHC) showing high efficacy in the inhibition of B. cinerea growth. Both formulations were evaluated in on-farm greenhouse trials conducted for two seasons (2019/2020 and 2020/2021) in three greenhouses located in Almería, Spain. In terms of controlling Botrytis, PHC showed efficacy results comparable to or even better than those that have been obtained for copper oxychloride. Weather conditions outside and inside the greenhouse were conducive to the onset and development of the disease. Tomato variety selection and pruning practices (flush cuttings) were the main factors that reduced the use of copper-based formulations or any other fungicide to prevent grey mould infection. Smart and integrated management of the mentioned factors could lead to the substitution of copper to control Botrytis in the crop system studied here.
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