|
|
|
| Registros recuperados: 10 | |
|
|
| VARGAS,ALEXANDER O. |
| It has been argued that the study of natural selection and quantitative genetics should have a central role in evolutionary thinking and undergraduate teaching in Chile. Extensive operational use of the concept of natural selection may seem consistent with this argument. However, advances of evolutionary knowledge in independent fields such as phylogenetic analysis, developmental evolution, and paleontology cannot be ignored. I argue here that the role of natural selection in contemporary evolutionary biology can be compared to that of Newtonian mechanics in contemporary physics: it can describe a given domain of observations, but it is insufficient to handle the different sources of evolutionary knowledge. Overemphasis on natural selection as the... |
| Tipo: Journal article |
Palavras-chave: Evolution; History; Development; Epigenesis; Drift. |
| Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000400012 |
| |
|
|
| Azizpanah, Amir; Rajabipour, Ali; Alimardani, Reza; Kheiralipour, Kamran; Ghamari, Bahram; Mohammadi, Vahid. |
| Spray drift study for reducing environmental hazards and protecting crops is of high importance as the pesticides used today are more active and many are non-selective. Drift potential can be restricted by assessing and optimizing equipment design, application parameters, the liquid spray properties, type of formulation and environmental conditions. The aim of this research was to design, construct and assess an intelligent system to determine the level of the spraying drift. The main parts of the system were liquid supply mechanism, pipes and nozzles, a controlled pneumatic system to pressurize the liquid, a nozzle moving system with a controlling panel and a tunnel for wind providing and control. To assess the performance of sprayer and drift of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sprayer; Wind tunnel; Drift; Volumetric mean diameter.. |
| Ano: 2015 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3308 |
| |
|
|
| Bialetzki,Andréa; Sanches,Paulo Vanderlei; Cavicchioli,Maristela; Baumgartner,Gilmar; Ribeiro,Ricardo Pereira; Nakatani,Keshiyu. |
| Analysis of drift of ichthyoplankton in two channels in the River Paraná, Brazil, were made. Sampling was undertaken from October 1995 to April 1996 during nychthemeral cycles. Water samples were collected to determine several environmental variables. Eggs densities largely differed to layers, times of day and months. In both the channels, highest occurrence of eggs was detected between January and March; greater concentrations at the bottom, during night. With regard to larvae, densities were significantly different in channels, times of days and months. Maximum occurrences were seen in the right channel, in both layers, with largest capture between January and March. Surface of the both channels presented highest density of larvae during night. Water... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Drift; Ichthyoplankton; Paraná River. |
| Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89131999000100008 |
| |
|
|
| Di Prinzio,Alcides; Behmer,Sergio; Magdalena,Jorge; Chersicla,Germán. |
| Only part of the active ingredient used in agrochemical applications in orchards is retained on the trees. The product that is not retained is lost as sedimentation in the soil and as drift, the latter being a major source of environmental pollution. Unfavorable atmospheric conditions affect the uniformity of distribution and increase product loss. This can be mitigated by the utilization of larger drops. The objective of the present work was to evaluate the effect of service pressure on distribution in the trees and product loss by using a conventional hydro pneumatic sprayer. A fluorescent tracer was applied on fruit trees by an airblast sprayer, with two treatments: high pressure (1800 kPa) and low pressure (500 kPa). Samples were collected from the... |
| Tipo: Journal article |
Palavras-chave: Orchards; Sprayers; Drift; Service pressure. |
| Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000400020 |
| |
|
|
| Ardhuin, Fanny; Ezraty, Robert. |
| Satellites enable daily and global coverage of the polar oceans and provide a unique monitoring capability of sea ice dynamics. Sea ice drift maps can be estimated in Arctic from several satellite sensors, particularly from scatterometers and radiometers. This study presents the benefits of combining single drift fields at the same resolution into a "merged" field, built at three-and six-day lags during winters with a 62.5-km resolution. It is shown that combining these drift fields not only increases the reliability of the displacement estimation and the number of estimated vectors to almost a full ice covered area but also expands the time period over which these estimations are reliable from freeze until the melt onset. The autumn-winter-spring sea ice... |
| Tipo: Text |
Palavras-chave: Arctic; Advanced Scatterometer (ASCAT); Drift; Merging; Scatterometry; Sea ice. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00088/19895/17729.pdf |
| |
|
|
| Behmer,Sergio; Di Prinzio,Alcides; Striebeck,Guillermina; Magdalena,Jorge. |
| Fruit production demands several phytosanitary treatments per year. The efficiency of these treatments is affected by product loss because of drift, a situation that is aggravated by frequent high winds and the presence of a substantial rural population. The objective of this study was to evaluate the distribution and to quantify product losses in fruit orchard applications. Fluorescent tracers with air-blast sprayers were applied, using air-induction hollow cone nozzles, compared to conventional hollow cone nozzles. To evaluate drift, pipes cleaner were placed on columns behind the adjacent row to the treated one, and for the losses under the tree, Petri dishes were located below the treated row; for the distribution in the tree, leaves were collected... |
| Tipo: Journal article |
Palavras-chave: Orchards; Sprayers; Drift; Air-induction nozzles. |
| Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000300017 |
| |
|
|
| Moreira, A.; Alfonso, A.. |
| Sargassum fluitans y Sargassum natans son macroalgas pardas holopelágicas que se pueden agregar para formar extensas masas flotantes en la superficie del Atlántico Norte (Mar de los Sargazos). El presente trabajo describe la ocurrencia de una excesiva arribazón de Sargassum fluitans en la costa este de la provincia de Cienfuegos, región centro-sur de Cuba, en mayo de 2012. El mayor impacto de la arribazón por efecto mecánico sobre la costa fue reportado en el sector turístico. Se observaron condiciones meteorológicas atípicas durante la arribazón de Sargassum. |
| Tipo: Journal Contribution |
Palavras-chave: Drift; Algae resources. |
| Ano: 2013 |
URL: http://hdl.handle.net/1834/5248 |
| |
|
|
| Carvalho, Felipe Paolinelli de; Universidade Federal de Viçosa; França, André Cabral; Universidade Federal dos Vales do Jequitinhonha e Mucuri; Lemos, Vinícius Teixeira; Universidade Federal de Lavras; Ferreira, Evander Alves; Universidade Federal dos Vales do Jequitinhonha e Mucuri; Santos, José Barbosa dos; Universidade Federal dos Vales do Jequitinhonha e Mucuri; Silva, Antonio Alberto da; Universidade Federal de Viçosa. |
| Farmers use non-selective herbicides, such as glyphosate, in directed applications to control weeds in coffee crops. Despite the precautions used during the application of herbicides, there are usually reports of poisoning in plantation areas. Moreover, it is fundamental to understand the effects of glyphosate on photosynthetic processes. The present study aimed to evaluate the characteristics associated with the photosynthetic activity in coffee cultivars subjected to doses of glyphosate. The experiment was conducted in a greenhouse using three varieties of coffee (Coffea arabica), including Acaiá (MG-6851), Catucaí Amarelo (2 SL) and Topázio (MG-1190), and three subdoses of glyphosate (0.0, 115.2 and 460.8 g ha-1) in a 3 x 3 factorial scheme. Herbicide... |
| Tipo: Pesquisa empírica |
Palavras-chave: 5.01.03.00-8 herbicide; EPSPs; Coffea arabica; Photosynthetic rate; Drift Fitotecnia herbicide; EPSPs; Coffea arabica; Photosynthetic rate; Drift. |
| Ano: 2012 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/15440 |
| |
|
| |
|
|
| Ardhuin, Fanny; Ezraty, Robert. |
| Satellites enable daily and global coverage of the polar oceans, providing an unique monitoring capability of sea ice dynamics over Arctic and Antarctic. Available geophysical parameters include ice concentration, extent, type and sea ice drift. Backscatter map from SeaWinds/QuikSCAT and brightness temperature maps from Special Sensor Microwave Imager (SSM/I) are available at a pixel resolution of 12,5 km from which ice drift can be estimated for each sensor. Since 1999, IFREMER makes available a "Merged" sea ice drift data set based on the combination of these drifts at 3 and 6-day lags at the grid resolution of 62,5 km. It has been demonstrated that combining these drifts increases the number of valid vectors. In this paper, the validation of this... |
| Tipo: Text |
Palavras-chave: Arctic; Buoys; Drift; Sea ice; AMSR E; Radiometer; Scatterometer; Arctique; Bouées; Dérive; Glaces de mer; AMSR E; Radiomètre; Diffusiomètre. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-1292.pdf |
| |
| Registros recuperados: 10 | |
|
|
|
