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1.
Sci Total Environ ; 845: 157292, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35820523

RESUMO

Improvements in the spray application of plant protection products enhance agricultural sustainability by reducing environmental contamination, but by increasing food quality and human safety. Currently, Unmanned Aerial Vehicles (UAVs) are raising interest in spray applications in 3D crops. However, operational configurations of UAV-spray systems need further investigation to maximise the deposition in the canopy and minimise the off-target losses. Our experimental research focused on investigating the effects on the canopy spray deposition and coverage due to different UAV-spray system configurations. Twelve configurations were tested under field conditions in an experimental vineyard (cv. Barbera), derived from the combination of different UAV flight modes (band and broadcast spray applications), nozzle types (conventional and air inclusion), and UAV cruise speeds (1 and 3 m s-1). Also, the best treatment, among those tested, by using the UAV-spray system and a traditional airblast sprayer were compared. The data was analysed by testing the effects of the three operational parameters and their two- and three-way interactions by means of linear mixed models. The results indicated that the flight mode deeply affects spray application efficiency. Compared to the broadcast spray modes, the band spray mode was able to increase the average canopy deposition from 0.052 to 0.161 µL cm-2 (+ 309 %) and reduce the average ground losses from 0.544 to 0.246 µL cm-2 (- 54 %). The conventional airblast sprayer, operated at a low spray application rate, showed higher canopy coverage and lower ground losses in comparison to the best UAV-spray system configuration.


Assuntos
Agricultura , Produtos Agrícolas , Agricultura/métodos , Fazendas , Humanos
2.
Neotrop Entomol ; 48(1): 50-56, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29949122

RESUMO

Pitfall traps are commonly used for the collection of terrestrial insects in ecology and biology studies; they are relatively straightforward to manufacture and there is a large variety of models described in the literature. However, they present a few drawbacks: (i) the removal and transport of the collected material are not practical; (ii) they have low resistance and durability; (iii) they fail to correctly protect the attractive bait against adverse weather conditions and scavengers, and (iv) evaporation of the liquid used inside the trap. We proposed an optimized pitfall trap design for terrestrial insect collection made from cheap and easily accessible materials. The new design allows the transfer of the collected material to the lab by removing only that part of the trap where the insects have been captured; the other part remains in its original place. Thus, the proposed trap allows easier operation since there is no need to transport water to replenish the traps after each transfer; in addition, there is less volume and weight to be carried. The trap can remain in the field for months because of the durability of its material. Furthermore, the collected material is better protected against adverse weather conditions and scavengers. Currently, an efficient and rapid sampling strategy in the field is of global interest to understand mechanisms that can contribute to the monitor changes in phenology, succession, and biodiversity.


Assuntos
Biodiversidade , Ecologia/instrumentação , Entomologia/instrumentação , Insetos , Animais
3.
Sci Total Environ ; 616-617: 805-815, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29111253

RESUMO

Pneumatic sprayers are widely used in vineyards due to their very fine droplet size, which makes the drift risk to become an important problem to be considered. The aim of this study was to assess the effect of the spout diameter at the release point on the spray droplet size and uniformity achieved for different liquid flow rates (LFR) and air flow rates (AFR). A test bench was developed to simulate a real pneumatic sprayer under laboratory conditions, and it was empirically adjusted to match the air pressure conditions as closely as possible to real working conditions. Two positions of insertion of the liquid hose, the conventional position (CP) and an alternative position (AP), were tested for three LFRs, 1.00, 1.64, and 2.67Lmin-1, and four AFRs, 0.280, 0.312, 0.345, and 0.376m3s-1. The air speed decrease between the two insertion points of the liquid hose was measured. A Malvern SprayTec® instrument was used to measure the droplet size, and the D50, D10, and D90 parameter values were obtained. The relative SPAN factor (RSF) was also calculated. A model to predict variations in D50 was fitted using the aforementioned parameters. The results show that variations in the diameter of the spout significantly change the droplet size, producing a mean increase of 59.45% in D50 and similar increases in D10 and D90. The model developed to predict variations in D50 has a very high degree of accuracy (R2=0.945). The relative decrease in the air speed along the spout did not present significant differences for the different airflow rates tested. The results of the study show that the droplet size produced in pneumatic spraying can be modified easily by varying the air spout dimensions. This should be taken into account by manufacturers from a design point of view.

4.
Pediatr Med Chir ; 36(5-6): 103, 2014 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-25669894

RESUMO

Children have an high risk of renal damage as a result of blunt trauma. Conservative management is always recommended for lower grades (I to III) but is rather controversial whenever high grade injuries (grade IV and V) are concerned. We describe a case of successful conservative management in grade IV renal injury occurred in a 9-years-old girl with blunt trauma.


Assuntos
Rim/lesões , Stents , Ferimentos não Penetrantes/complicações , Criança , Drenagem/métodos , Feminino , Humanos , Rim/patologia , Tratamentos com Preservação do Órgão/métodos , Ferimentos não Penetrantes/patologia , Ferimentos não Penetrantes/terapia
5.
J Med Chem ; 43(25): 4726-37, 2000 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11123981

RESUMO

A series of allosteric effectors of hemoglobin, 2-(aryloxy)-2-alkanoic acids, was prepared to investigate the effect of the stereocenter on allosteric activity. The chiral analogues were based on the lead compound, RSR13 (3b), with different alkyl/alkanoic and cycloalkyl/cycloalkanoic groups positioned at the acidic chiral center. Of the 23 racemic molecules synthesized, 5 were selected for resolution based on structure-activity relationships. One chiral analogue, (-)-(1R,2R)-1-[4-[[(3, 5-dimethylanilino)carbonyl]methyl]phenoxy]-2-methylcyclopentane carbox ylic acid (11), exhibited greater in vitro activity in hemoglobin solutions than its antipode, racemate, and RSR13. Compound (-)-(1R, 2R)-11 was equipotent with RSR13 in whole blood, is a candidate for in vivo animal studies, and if efficacious and safe has a potential for use in humans. In general, it was found that chirality affects allosteric effector activity with measurable differences observed between enantiomers and the racemates.


Assuntos
Acetatos/síntese química , Compostos de Anilina/química , Hemoglobinas/química , Propionatos/química , Acetatos/sangue , Acetatos/química , Regulação Alostérica , Compostos de Anilina/sangue , Derivados de Benzeno , Cristalografia por Raios X , Hemoglobinas/metabolismo , Humanos , Modelos Moleculares , Oxigênio/metabolismo , Propionatos/sangue , Estereoisomerismo , Relação Estrutura-Atividade
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