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The recognition of traps most likely to contain hydrocarbons, while making reconnaissance surveys or at an early stage of exploration, has never been an easy task. Utilizing mathematical indicators can allow the identification of ...
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The recognition of traps most likely to contain hydrocarbons, while making reconnaissance surveys or at an early stage of exploration, has never been an easy task. Utilizing mathematical indicators can allow the identification of likely traps containing oil and/or gas accumulation during early exploratory drilling programs. The guidelines set forth in this article permit one to refine the exploration and delineation operations and focus exploration efforts on only those traps that are most likely to contain economic hydrocarbons. This "focusing" saves valuable time and economic resources.
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We monitored four groups of Hymenoptera in organic apple orchards in New Zealand in order to assess different trapping methods. The factors assessed were trap type (pan traps vs. sticky traps), trap colour, preservative type and t...
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We monitored four groups of Hymenoptera in organic apple orchards in New Zealand in order to assess different trapping methods. The factors assessed were trap type (pan traps vs. sticky traps), trap colour, preservative type and trap position within the orchard with regard to the shelterbelt.
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We monitored four groups of Hymenoptera in organic apple orchards in New Zealand in order to assess different trapping methods. The factors assessed were trap type (pan traps vs. sticky traps), trap colour, preservative type and t...
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We monitored four groups of Hymenoptera in organic apple orchards in New Zealand in order to assess different trapping methods. The factors assessed were trap type (pan traps vs. sticky traps), trap colour, preservative type and trap position within the orchard with regard to the shelterbelt.
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A radial inhomogeneous magnetic field produced by counter-propagating currents in anti-Helmholtz configuration coils has been superimposed to a Penning trap. The confinement properties of electrons in such a trap have been studied...
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A radial inhomogeneous magnetic field produced by counter-propagating currents in anti-Helmholtz configuration coils has been superimposed to a Penning trap. The confinement properties of electrons in such a trap have been studied experimentally. Without the radial B-field we find a number of operating conditions where instabilities occur, arising from higher order contributions to the quadrupolar trapping field. When we apply the radial field the trap properties remain essentially unchanged until the strength of this field at the boundary of the electron cloud is of the same order as the homogeneous Penning field. Then a sudden breakdown in the confinement appears. The experiments have been performed in low magnetic fields. The equations of motions of the trapped particles can be cast in a dimensionless form and our results can be considered as independent of the field strength.
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Phlebotominae are the vectors of Leishmania parasites. It is important to have available surveillance and collection methods for the sand fly vectors. The objectives of the present study were to evaluate and compare traps for the ...
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Phlebotominae are the vectors of Leishmania parasites. It is important to have available surveillance and collection methods for the sand fly vectors. The objectives of the present study were to evaluate and compare traps for the collection of sand fly species and to analyze trap catches along months and transects. Field evaluations over a year were conducted in an endemic area of leishmaniasis in the state of Quintana Roo, Mexico. A randomized-block design was implemented in study area with tropical rainforest vegetation. The study design utilized 4 transects with 11 trap types: 1) Centers for Disease Control and Prevention (CDC) light trap with incandescent bulb (CDC-I), 2) CDC light trap with blue light-emitting diodes (LEDs) (CDC-B), 3) CDC light trap with white LEDs (CDC-W), 4) CDC light trap with red LEDs (CDC-R), 5) CDC light trap with green LEDs (CDC-G), 6) Disney trap, 7) Disney trap with white LEDs, 8) sticky panels, 9) sticky panels with white LEDs, 10) delta-like trap, and 11) delta-like trap with white LEDs. A total of 1,014 specimens of 13 species and 2 genera (Lutzomyia and Brumptomyia) were collected. There were significant differences in the mean number of sand flies caught with the 11 traps; CDC-I was (P = 0.0000) more effective than the other traps. Other traps exhibited the following results: CDC-W (17.46%), CDC-B (15.68%), CDC-G (14.89%), and CDC-R (14.30%). The relative abundance of different species varied according to trap types used, and the CDC-I trap attracted more specimens of the known vectors of Leishmania spp., such as like Lutzomyia cruciata, Lu. shannoni, and Lu. ovallesi. Disney trap captured more specimens of Lu. olmeca olmeca. Based on abundance and number of species, CDC light traps and Disney traps appeared to be good candidates for use in vector surveillance programs in this endemic area of Mexico.
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Numerical simulations of a solid-core polymer waveguide structure were performed to calculate the trapping efficiencies of particles with nanoscale dimensions smaller than the wavelength of the trapping beam. A three-dimensional (...
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Numerical simulations of a solid-core polymer waveguide structure were performed to calculate the trapping efficiencies of particles with nanoscale dimensions smaller than the wavelength of the trapping beam. A three-dimensional (3-D) finite element method was employed to calculate the electromagnetic field. The inlet and outlet boundary conditions were obtained using an eigenvalue solver to determine the guided and evanescent mode profiles. The Maxwell stress tensor was considered for the calculation of the transverse and downward trapping efficiencies. A particle at the center of the waveguide showed minimal transverse trapping efficiency and maximal downward trapping efficiency. This trend gradually reversed as the particle moved away from the center of the waveguide. Particles with larger surface areas exhibited higher trapping efficiencies and tended to be trapped near the waveguide. Particles displaced from the wave input tended to be trapped at the waveguide surface. Simulation of an ellipsoidal particle showed that the orientation of the major axis along the waveguide's lateral z-coordinate significantly influenced the trapping efficiency. The particle dimensions along the z-coordinate were more critical than the gap distance (vertical displacement from the floor of the waveguide) between the ellipsoid particle and the waveguide. The present model was validated using the available results reported in the literature for different trapping efficiencies.
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The choice of sampling methods to survey saproxylic beetles is a key aspect to assessing conservation strategies for one of the most endangered assemblages in Europe. We evaluated the efficiency of three sampling methods: baited t...
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The choice of sampling methods to survey saproxylic beetles is a key aspect to assessing conservation strategies for one of the most endangered assemblages in Europe. We evaluated the efficiency of three sampling methods: baited tube traps (TT), window traps in front of a hollow opening (WT), and emergence traps covering tree hollows (ET) to study richness and diversity of saproxylic beetle assemblages at species and family levels in Mediterranean woodlands. We also examined trap efficiency to report ecological diversity, and changes in the relative richness and abundance of species forming trophic guilds: xylophagous, saprophagous/saproxylophagous, xylomycetophagous, predators and commensals. WT and ET were similarly effective in reporting species richness and diversity at species and family levels, and provided an accurate profile of both the flying active and hollow-linked saproxylic beetle assemblages. WT and ET were the most complementary methods, together reporting more than 90 % of richness and diversity at both species and family levels. Diversity, richness and abundance of guilds were better characterized by ET, which indicates higher efficiency in outlining the ecological community of saproxylics that inhabit tree hollows. TT were the least effective method at both taxonomic levels, sampling a biased portion of the beetle assemblage attracted to trapping principles, however they could be used as a specific method for families such as Bostrichiidae, Biphyllidae, Melyridae, Mycetophagidae or Curculionidae Scolytinae species. Finally, ET and WT combination allows a better characterization of saproxylic assemblages in Mediterranean woodland, by recording species with different biology and linked to different microhabitat types.
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The most effective traps tested against western cherry fruit fly, Rhagoletis indifferens Curran, have been the Yellow Sticky Strip (YSS) rectangle made of styrene and the three-dimensional yellow Rebell cross made of polypropylene...
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The most effective traps tested against western cherry fruit fly, Rhagoletis indifferens Curran, have been the Yellow Sticky Strip (YSS) rectangle made of styrene and the three-dimensional yellow Rebell cross made of polypropylene. However, three-dimensional YSS styrene traps have never been tested against this or any other fruit fly. The main objectives of this study were to determine the efficacies of 1) YSS cross, Rebell cross, YSS cylinder, and YSS rectangle traps, 2) Rebell cross versus Rebell rectangle traps, and 3) YSS tent versus YSS rectangle traps for R. indifferens. For 1), the YSS cross caught more flies than the Rebell cross of equivalent surface area and more than a smaller YSS cylinder, but not any more than a YSS rectangle of similar surface area as the YSS cross. For 2), a Rebell cross caught more flies than a rectangle of equivalent surface area made of Rebell panels. For 3), YSS tent and YSS rectangle traps of equivalent surface area did not differ in fly captures. Results suggest that the YSS cross was more effective than the Rebell cross due to its color and that when trap color is highly attractive, three-dimensional shape may be unimportant, whereas it could be when trap color is less attractive. A new trap modeled after the YSS cross, compact but with high trap surface area to increase fly captures, could be an effective option or addition to rectangles for monitoring R. indifferens.
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The present research studies "Comparative efficacy of some trapping techniques to control porcupine, wild boar and other vertebrate pests" was carried out in three rural sites i.e. Chak No. 33/J.B, 126/J.B and 197/J.B. of Faisalab...
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The present research studies "Comparative efficacy of some trapping techniques to control porcupine, wild boar and other vertebrate pests" was carried out in three rural sites i.e. Chak No. 33/J.B, 126/J.B and 197/J.B. of Faisalabad Division, during 2002. In all the cases, the efficacy of the traps was found to enhance significantly by using different attractants. Selection of attractant was another impotent decision. Normally the material used to lure the animal was not naturally present in the field as crop e.g. maize grains were used when it was not sown in the field as crop etc. Under present studies, three types of traps namely Panel Trap, Fahad Trap and Loop Trap were tested in the fields. Relative efficiency of each trap was measured in capturing the animals to reduce damage on maize, wheat and sugar cane crops caused by porcupines, wild boars and other vertebrate pests. The Panel trap was found to be the most efficient with trapping rate of 70.83%. However for porcupine, its design was reshaped and trap floor was built with wire gauze to arrest their escape. New shape of the Panel trap was found to be excellent in restricting escape of the porcupines by burrowing through the trap floor. The Panel trap is little costly whereas Loop trap isthe most economical, simple and easy to handle with a relatively efficiency of 53.84%. Efficiency of Fahad traps was 48.57%. Results of present study revealed that the efficacy of Panel trap was found to be the maximum followed by Loop and Fahad trap.
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Methods for detecting and for monitoring Prostephanus truncatus (Horn) are crucial components in phytosanitary control, research programmes and pest management against this beetle. P. truncatus is unusual in that its populations a...
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Methods for detecting and for monitoring Prostephanus truncatus (Horn) are crucial components in phytosanitary control, research programmes and pest management against this beetle. P. truncatus is unusual in that its populations are distributed widelybetween natural habitats and stores holding maize grain and dried cassava roots, which necessitates a similarly wide range of sampling methodologies. This review considers successful and unsuccessful approaches to sampling the pest populations in both stores and the natural environment and concludes with a consideration of how monitoring could contribute to integrated pest management for P. truncatus.
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