Standard Trap Research Articles

Creating versatile atom traps by applying near-resonant laser light in magnetic traps

We utilize the combination of two standard trapping techniques, a magnetic trap and an optical trap in a Raman setup, to propose a versatile and tunable trap for cold atoms. The created potential provides several advantages over conventional trapping potentials. One can easily convert the type of the trap, for example, from a single-well to a double-well trap. Atoms in different internal states can be trapped in different trap types, thereby enabling the realization of experiments with multicomponent Bose-Einstein condensates. Moreover, one can achieve variations of the trapping potential on small length scales without the need of microstructures. We present the potential surfaces for different setups, demonstrate their tunability, give a semianalytical expression for the potential, and propose experiments which can be realized within such a trap.

Boll Weevil (Coleoptera: Curculionidae) Response to and Volatilization Rates of Grandlure When Combined With Varying Doses of Eugenol in the Extended-Life Pheromone Lure

Boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), trapping and pheromone quantitative analysis of extended-life pheromone lures manufactured with 0, 10, 20, and 30 mg of eugenol was conducted in the Rio Grande Valley of Texas under spring and summer conditions. Boll weevils responded positively to eugenol on one of 12 trapping weeks when densities were high, but when densities were low (<2 weevils trap(-1) wk(-1)), there were no significant differences in captures for any dosage of eugenol offered in a standard boll weevil trap. Weekly grandlure volatilization did not differ by eugenol dose but was significantly different when evaluated over three different trapping periods and by week within trapping period due to differences in ambient temperature. The amount of grandlure that remained after 4 wk in moderate temperatures of spring was 13.1 +/- 0.19 mg (55.7% of original 25 mg of content) compared with 5.5 +/- 0.15 mg remaining (22.8% of original 25 mg content) after for 4 wk in summer heat. Weekly volatilization of grandlure for the summer trapping period was 9.8 +/- 0.32 mg for the first week, declining steadily to 1.0 +/- 0.09 mg by the fourth week of age. The data indicate that at high summer temperatures >30 degrees C, accumulative grandlure loss per week may be too high, leaving too little residual grandlure to effectively attract boll weevils at the end of 3 wk of trapping. Eugenol plays no role in reserving or encouraging the release of grandlure, or in increasing boll weevil captures when boll weevil densities are low.

Stability of a fully polarized ultracold Fermi gas near zero-crossing of a p-wave Feshbach resonance

We consider a fully polarized ultracold Fermi gas interacting through a p-wave Feshbach resonance. Using a two-channel model, we find the effective potential at the point where the p-wave scattering length goes to zero. Here the effective interaction provides attraction and one can therefore ask about the stability of the system. We calculate the energy density of the system in the Thomas-Fermi approximation, determine the profile of the gas, and the critical number of particle in the system as function of the relevant interaction parameters. The instability can be inferred from a simple breathing mode argument which explains the scaling found numerically. The critical particle number turns out to be extremely large unless the external confinement is very tight. We therefore conclude that the effect is insignificant for standard trapping potentials and that the magnetic dipole interaction is the important term at zero scattering length. However, for tight confinement as in an optical lattice higher-order corrections can become important.

Description of the IMR Standard Light Trap and the Vertical Distribution of Some Decapod Larvae (Homarus and Nephrops)

The construction of different versions of a cheap, robust, and easy to operate light trap for catching various aquatic organisms is shown. The trap can be used to > 300 m depth and meets a number of criteria. Small-scale vertical distribution of decapod larvae was investigated during trap trials. The traps (6-10) were set for 24 h at different depths, once a week, between 25 July and 28 September 2006, within the Kåvra lobster reserve at the Swedish west coast. This is an area with low salinity in the surface water during summer due to outflow of water from the Baltic Sea. The larvae of the European lobster Homarus gammarus (stage I) and Norway lobster Nephrops norvegicus (stages I-III) were found within and below the thermo- and haloclines. No larvae were found within the upper 2 m. This finding may have important bearings on the larval transport by currents and increase the possibility for retention of larvae, but was not tested inthis study. The highest catches of both H. gammarus and N. norveigicus were obtained during August. The trap appears to be well suited for investigating small-scale vertical distribution during the dark period, and for collecting animals in good condition. However, the trap did notcatch all larval stages, and the relation between light intensity (both natural and trap light) and catch ability is unknown.

Observation of electromagnetically induced transparency and slow light in the dark state - bright state basis

The quantum coherence phenomenon of electromagnetically induced transparency (EIT) is observed in a three-level system composed of an excited state and two coherent superpositions of the two ground-state levels. This peculiar ground state basis is composed of the so-called bright and dark states of the same atomic system in a standard coherent population trapping configuration. The characteristics of EIT, namely, width of the transmission window and reduced group velocity of light, in this unusual basis, are theoretically and experimentally investigated and are shown to be essentially identical to those of standard EIT in the same system.

Microfabricated evanescent-light funnel with high-intensity cold atom flux

We process a silicon-on-insulator substrate into a funnel with a 25-μm-side square-shaped outlet by photolithography and anisotropic chemical etching. The funnel is utilized to form a cold atomic beam by means of reflection and cooling on repulsive evanescent light. Monte Carlo simulations show that the flux intensity of emitted cold Rb atoms reaches 10 12 cm −2 s −1. The mean horizontal velocity is estimated to be below 10 cm/s, while the mean vertical velocity decreases in proportion to the outlet side. The evanescent-light funnel can be developed to concentrate 80% of Rb atoms falling from a standard magneto-optical trap.

Seasonal and diel patterns of biting midges (Ceratopogonidae) and mosquitoes (Culicidae) on the Parris Island Marine Corps Recruit Depot

The Marine Corps Recruit Depot on Parris Island, SC, is surrounded by tidal salt marshes, which are breeding habitats for many pestiferous biting flies. Knowledge of biting fly behavior patterns is needed to develop effective pest management strategies in urban areas adjacent to salt marshes. We measured biting midge (Ceratopogonidae) and mosquito (Culicidae) seasonal abundance and diel activity patterns on Parris Island using CO(2)-baited suction traps from November 2001 - November 2004. Of the three biting midge species collected, Culicoides furens was most abundant (86.2% of total) and was present in high numbers from late March to November. Culicoides hollensis (12.0% of total) was present during spring and fall but absent in summer and winter; and Culicoides melleus (1.7% of total) was present in spring through fall but absent in winter. Abundance of C. furens had a positive linear correlation with air temperature and rainfall. There were nonlinear correlations between air temperature and C. hollensis and C. melleus numbers, which were most abundant at moderate temperatures. Of 18 mosquito species collected, the most abundant were Aedes taeniorhynchus (42.7% of total), Aedes sollicitans (26.3% of total), Culex salinarius (15.6% of total), Culex quinquefasciatus (7.3% of total), and Aedes vexans (5.7% of total); other species comprised <5% of collections. Aedes taeniorhynchus numbers were positively correlated with temperature and rainfall, and Cx. salinarius was correlated with soil moisture. Activity of most biting midges and mosquitoes were highest the first two hours following sunset. Species of biting flies were present in all months, suggesting that year-round control measures are necessary to reduce exposure to potential disease vectors and nuisance biting.

Standard random walks and trapping on the Koch network with scale-free behavior and small-world effect

A vast variety of real-life networks display the ubiquitous presence of scale-free phenomenon and small-world effect, both of which play a significant role in the dynamical processes running on networks. Although various dynamical processes have been investigated in scale-free small-world networks, analytical research about random walks on such networks is much less. In this paper, we will study analytically the scaling of the mean first-passage time (MFPT) for random walks on scale-free small-world networks. To this end, we first map the classical Koch fractal to a network, called Koch network. According to this proposed mapping, we present an iterative algorithm for generating the Koch network; based on which we derive closed-form expressions for the relevant topological features, such as degree distribution, clustering coefficient, average path length, and degree correlations. The obtained solutions show that the Koch network exhibits scale-free behavior and small-world effect. Then, we investigate the standard random walks and trapping issue on the Koch network. Through the recurrence relations derived from the structure of the Koch network, we obtain the exact scaling for the MFPT. We show that in the infinite network order limit, the MFPT grows linearly with the number of all nodes in the network. The obtained analytical results are corroborated by direct extensive numerical calculations. In addition, we also determine the scaling efficiency exponents characterizing random walks on the Koch network.

MAMMALIAN PREY OF BARN OWL (TYTO ALBA) IN SOUTHEASTERN OAXACA, MÉXICO

The analysis of pellet contents of Barn Owls from southeastern Oaxaca, Mexico, shows that mammals represent the main prey of this bird. We identified a minimum of 184 individuals from 2 orders, 3 families and 8 species of mammals. The greatest number of prey was from hispid cotton rat (Sigmodon hispidus), which represented 83.69% of the total individuals and 84.68% of the biomass of the sample. From the other 7 species included in the pellets, 3 were very uncommon species: the cozumelan golden bat (Mimon cozumelae), the false vampire bat (Vampyrum spectrum), and the Peter’s climbing rat (Tylomys nudicaudus). Bats represented 2.17% of prey number and 0.799% of the total biomass estimated in the sample. Comparisons of these results with the estimated abundances by standard trapping methods show differences. These results corroborate a general pattern of barn owl opportunistic predation over the locally most abundant species and bats as rare prey.

Evaluation of Six Mosquito Traps for Collection of Aedes albopictus and Associated Mosquito Species in a Suburban Setting in North Central Florida1

We compared 6 adult mosquito traps for effectiveness in collecting Aedes albopictus from suburban backyards with the goal of finding a more suitable surveillance replacement for the Centers for Disease Control and Prevention (CDC) light trap. Trap selection included 2 commercial propane traps (Mosquito Magnet Professional trap and Mosquito Magnet Liberty trap), 2 Aedes-specific traps (Fay-Prince Omnidirectional trap and Wilton trap), 1 experimental trap (Mosquito Magnet-X trap), and a standard surveillance CDC light trap that served as a control. Traps that did not generate carbon dioxide were provided with bottled CO2 at a flow rate of 500 ml/min. Those traps designed for use with chemical attractants (Mosquito Magnet traps) were baited with Lurex (L-lactic acid) and octenol (1-octen-3-ol) commercial baits, known attractants to Ae. albopictus. Three repetitions of a 6 x 6 Latin square test yielded a total of 37,237 mosquitoes, of which 5,280 (14.2%) were Ae. albopictus. Significantly more (P < 0.05) Ae. albopictus were collected from the experimental and commercial traps (4,244/5,280; 80.3%) than from the CDC light trap and Aedes-specific traps. The Mosquito Magnet Liberty collected the most Ae. albopictus (1,591), accounting for 30.1% of the total take, followed closely by the Mosquito Magnet-X (1,468) and the Mosquito Magnet Pro (1,185). The omnidirectional Fay-Prince trap performed better than the CDC or Wilton trap. Twenty-seven mosquito species were collected during these trials, 9 species in large enough numbers for meaningful analysis. Aedes albopictus was the second most common mosquito trapped. The results of these trials indicate that propane-powered commercial traps would serve as useful substitutes in lieu of CDC traps in Ae. albopictus surveillance efforts. Trap features advantageous for collecting Ae. albopictus and other mosquito species are discussed.

The Patient-Specific Brace Design and Biomechanical Analysis of Adolescent Idiopathic Scoliosis

Brace application has been reported to be an effective approach in treating mild to moderate idiopathic adolescent scoliosis. However, little attention is focused on the biomechanical study of patient-specific brace treatment. The purpose of this study was to propose a design method of personalized brace and to analyze its biomechanical behavior and to compare the brace forces with the I-Scan measurement system. Based on a three-dimensional patient-specific finite element model of the spine, rib cage, pelvis, and abdomen, a parametric patient-specific model of a thoracolumbosacral orthosis was built. The interaction between the torso and the brace was modeled by surface-to-surface contact interface. Three standard strap tensions (20 N, 40 N, and 60 N) were loaded on the back of the brace to simulate the strap tension. The I-Scan distribution pressure measurement system was used to measure the different region pressures, and the equivalent forces in these regions were calculated. The spinal curve changes and the forces acted on the brace generated by the strap tension were evaluated and compared with the measurement. The reduction in the coronal curvature was about 60% for a strap tension of 60 N. The sacral slope and the lordosis were partially reduced in this case, but the kyphosis had no obvious change. The brace slightly modified the axial rotation at the apex of the scoliotic curve. The forces generated in finite element analysis were approximately in good agreement with the measurement. The design and biomechanical analysis methods of patient-specific brace should be useful in the design of more effective braces.

Impact of trapping and handling on Leukocyte Coping Capacity in bank voles (Clethrionomys glareolus) and wood mice (Apodemus sylvaticus)

AbstractSmall mammals are routinely live-trapped and subsequently handled for a range of ecological and behavioural studies. Despite the techniques commonly employed being potentially stressful for the individual animals involved, it has hitherto been difficult to quantify the physiological impact. Here, we report on the first instance of using the Leukocyte Coping Capacity technique (LCC) in bank voles(Clethrionomys glareolus)and wood mice(Apodemus sylvaticus)to investigate the physiological impact of routine trapping and handling techniques. Twenty microlitres of blood were obtained from 40 animals, of which 25 were handled following standard protocols and 15 were not. We found that even a short period of acute stress is sufficient to trigger an immune response which was measurable using the LCC technique. These results further validate the use of the LCC technique for measuring the physiological impact of standard trapping and handling treatments on wild mammals.

Water Quality Improvements Using Modified Sediment Control Systems on Construction Sites

A study of the water quality of discharges from three different sediment control systems was conducted on a large construction site in North Carolina. Samples were obtained during storm events at the outlets of 11 of these systems using automatic samplers. Turbidity and total suspended solids (TSS) were measured, and a storm-weighted average (SWA) was determined for the systems. Water discharged from five standard sediment traps with rock dam outlets and unlined diversion ditches with rock check dams had an SWA turbidity of 4,320 nephelometric turbidity units (NTU) and an SWA peak of 12,640 NTU over a total of 26 storm events. The representative TSS values were 4,130 and 11,800 mg L-1, respectively. Measurements of runoff entering and exiting the traps suggested that heavy sediment was being captured, but turbidity was not reduced. Three traps with modifications including forebays, porous baffles, improved ditch stabilization (lining, additional check dams), and polyacrylamide application had SWA and peak turbidity of 990 and 1,580 NTU, respectively, over a total of 31 events. Total suspended solids were also much lower, at 740 and 1,810 mg L-1, respectively. Three basins with these same modifications, but with surface outlets, had somewhat higher average SWA values (1,560 NTU, 820 mg L-1), suggesting that the outlet type may not improve discharge water quality above the benefits of the other modifications to the standard sediment trap. However, when one of the latter systems was at optimal function, turbidity was reduced to below the receiving stream water levels (<100 NTU). These results strongly suggest that relatively simple modifications of commonly employed sediment trapping systems can dramatically improve discharge water quality and reduce the impacts on receiving waters.

Response of Tortricid Moths and Non-Target Insects to PheromoneTrap Color in Commercial Apple Orchards

Pheromone traps are a widely-used tool for monitoring pest activity in commercial apple orchards. Studies were conducted to evaluate delta-style traps painted with different colors (orange, red, yellow, green, blue, and white) for capture of obliquebanded leafroller, Choristoneura rosaceana (Harris), and oriental fruit moth, Grapholita molesta (Busck), as well as nontarget muscoid flies (Diptera: Muscidae) and honeybees, Apis mellifera L. An additional study evaluated plastic, four-sided LepTrap® traps of various colors in comparison with a standard delta trap for capture of obliquebanded leafroller, oriental fruit moth, tufted apple bud moth (Platynota idaeusalis (Walker)), and codling moth (Cydia pomonella L.). Capture of obliquebanded leafroller and oriental fruit moth was not significantly affected by trap color. Capture of nontarget flies and honeybees tended to be higher in blue and white (both painted and unpainted) delta-style traps in New York apple orchards, although there was some variability in this response by orchard site. There were no differences in capture of 4 pest species in Pennsylvania between colored, plastic LepTrap® traps and standard unpainted white delta-style traps. Given the observed differences in nontarget capture and the improved efficiencies of finding traps placed within tree canopies, we recommend using yellow, red, or orange delta traps for monitoring of obliquebanded leafroller, oriental fruit moth, and tufted apple bud moth in apple production areas in the eastern United States.

Grass strip corridors in agricultural landscapes enhance nest‐site colonization by solitary wasps

Corridors that connect otherwise isolated habitats have often been proposed as a management strategy to mitigate negative effects of habitat fragmentation. Non-crop corridors may have the potential to enhance the connectivity for arthropod predators in cropland landscapes, especially for species that require multiple habitats, such as cavity-nesting wasps which use wooded habitat for nesting and grassland habitat for foraging. However, the effects of corridors in nonexperimental landscapes have been rarely examined. We studied the species richness and abundance of cavity-nesting wasps and their parasitoids in standardized trap nests located in three habitat types (forest edge, hedge, grass strip) and in three grass-strip types (connected to a forest edge, slightly isolated, highly isolated from a forest edge). Species richness and the abundance of wasps (Hymenoptera: Sphecidae, Eumenidae, Pompilidae) were highest at forest edges, which provide natural nesting sites, and lowest in grass strips, with few natural nesting sites. Wasp abundance in grass strips connected to forest edges was 270% higher than in slightly isolated grass strips and 600% higher than in highly isolated grass strips. The abundance of caterpillar-hunting eumenid wasps was 600% higher in connected grass strips than in slightly and highly isolated grass strips. Species richness of wasps was enhanced by 180% in connected grass strips compared to highly isolated grass strips. Parasitism rates were not directly influenced by habitat or grass-strip type, but increased with increasing parasitoid diversity that was higher at forest edges than in grass strips. We conclude that grass-strip corridors enhance the colonization of nesting sites, presumably by facilitating wasp movements. In agricultural landscapes, where nesting sites are limited and food availability changes frequently, rapid colonization of nests may enhance population viability. Higher wasp abundance in connected nesting sites may be directly linked to higher biocontrol of pest caterpillars within the foraging range around nests. Although grass strips can reduce the negative effects of habitat fragmentation, non-crop habitats such as forest habitats and hedges providing nesting sites are required within the home range of wasps to allow reproduction in agricultural landscapes.

Efficacy of Novel Updraft Traps for Collection of Mosquitoes in Cairns, Australia

We conducted trials in Cairns, Australia, to examine if novel updraft light traps collected significantly more mosquitoes than the Centers for Disease Control and Prevention (CDC) model 512 miniature light trap. Two new updraft traps, the Northern Australia Quarantine Strategy (NAQS) Mozzie Trap and a CDC updraft trap, both collected significantly more mosquitoes than the standard CDC light trap, with a mean CDC Trap Index (trap collections relative to paired standard CDC light trap collections) of 3.3 and 2.3, respectively. These traps both had large horizontal suction areas that increased the probability that attracted mosquitoes entered the trap updraft. However, if the CO2 source was located within the updraft of the CDC updraft trap, mosquito collections decreased considerably, indicating that placement of the bait is critical to trap performance. Creating an updraft by simply inverting the CDC trap body did not increase collections. The Mosquito Magnet X trap also did not collect significantly more mosquitoes than the CDC trap. Two CDC light traps sharing a 600 ml CO2/min gas line collected ca. 50% more mosquitoes than a single CDC trap baited with 600 ml CO2/min, suggesting that a single gas source could be used on a trap line consisting of multiple trap units. These studies suggest that the optimal trap design should incorporate a CO2 release system that lures mosquitoes to a large updraft within a bowl-shaped trap intake.

Sampling parasitoid wasps (Insecta, Hymenoptera) in cacao agroforestry systems

We present Hymenoptera parasitoid family composition in a cacao agroforestry system, compare it among strata within the system, and evaluate three Malaise trap designs (yellow intercept, duplicated width and bottom addition), to test if: (1) new trap designs increase number of captured families; (2) number of families differ among strata; (3) stratum interferes in number of families captured by each trap type. Our data refer to only eight traps, with no actual replication of the combination of trap design with trap location; therefore, to make possible the statistical test of the hypotheses, we considered number of families captured per day as response variable, and included day as covariate to avoid pseudoreplication. We captured 9700 individuals, in 30 families. All trap adaptations increased number of families collected per day, when compared to standard Malaise trap. Most captures were made by yellow intercept and duplicated width traps. There was a significant interaction of trap type with stratum. Number of families captured per day differed among strata, the highest number of families occurring in cacao gap. Apresentamos a composição de famílias de parasitóides himenópteros em um sistema agroflorestal de cacao, comparamos a composição entre estratos deste sistema, e avaliamos três modificações em armadilhas Malaise (intercepto amarelo, largura duplicada e acréscimo de fundo), para testar se: (1) os modelos novos de armadilhas aumentam o número de famílias capturadas; (2) o número de famílias difere entre estratos; (3) estrato interfere no número de famílias capturadas por cada tipo de armadilha. Nossos dados provêm de apenas oito armadilhas, sem replicação verdadeira da combinação de modelo de armadilha com sua localização; assim, para possibilitar o teste estatístico das hipóteses, consideramos o número de famílias capturadas por dia como variável resposta, e para evitar pseudoreplicaçãor, incluímos dia como covariável. Capturamos 9700 indivíduos, de 30 famílias. Todas as modificações de armadilha aumentaram o número de famílias capturadas por dia, comparadas a armadilha Malaise padrão. A maioria das capturas ocorreu em armadilhas com intercepto amarelo ou largura duplicada. Houve interação significativa entre tipo de armadilha e estrato. O número de famílias capturadas por dia diferiu entre estratos, sendo o mais alto em lacunas sem cacao.

Exploitation of the sex pheromone of apple leaf midge Dasineura mali Kieffer (Diptera: Cecidomyiidae) for pest monitoring: Part 1. Development of lure and trap

In previous work, the female sex pheromone of the apple leaf midge, Dasineura mali (Kieffer) (Diptera: Cecidomyiidae), was identified by us as ( Z)-13-acetoxy-8-heptadecen-2-one. Only one enantiomer of the chiral compound was attractive to male midges but the racemic mixture was equally attractive. A series of replicated field experiments was carried out during 2004–2006 to develop an optimised pheromone trap system for monitoring populations of D. mali in commercial orchards. With rubber septa dispensers numbers of midges caught increased with increase in loading of pheromone over the range tested from 1 μg to 100 μg and a loading of 3 μg was found to be suitable for pest monitoring purposes. Polyethylene vial dispensers were unattractive during these tests. Release rate studies in the laboratory showed reasonably uniform release of pheromone from the septa for at least 574 days at 27 °C and 8 km/h wind speed. With the vials there was a delay of 10 days before the start of release of pheromone under these conditions. Funnel, bottle, Petri dish, delta and dish traps all caught midges, those with the larger catching surfaces being more sensitive. In practice, it was concluded that the standard delta trap is the best design for use by growers. The colour of the trap had no effect on attractiveness to D. mali males, but catches of non-target arthropods in red, green and black traps were significantly lower than in white, yellow or blue traps. The red traps are recommended for use by growers. Numbers of male midges caught were greatest in traps at ground level and decreased strongly with increasing height of trap deployment. A standard deployment height of 0.5 m was chosen. Males were attracted to traps over a distance of at least 50 m from an infested orchard. They showed a strong diurnal pattern of flight activity. Numbers caught rose steeply in the morning starting at 07:00 h (2 h after dawn), reached a peak at 09:00 h and steadily declined throughout the day thereafter. Conversely, numbers of ovipositing females were very low at 09:00 h but increased steadily, reaching a peak at 11:00–12:00 h and declining thereafter.

Cold Atom Trap with Zero Residual Magnetic Field: The ac Magneto-Optical Trap

A novel atom trap is described using alternating current to generate the magnetic B field, together with high speed polarization switching of the damping laser field. This combination produces a trap as effective as a standard magneto-optical trap (MOT), with the advantage that the average B field is zero. No net current is hence induced in surrounding conductive elements, and the B field produced by the ac MOT is found to switch off >300 times faster than a conventional MOT. New experiments can hence be performed, including charged particle probing or detection of the cold target ensemble.

Realization of a single-beam mini magneto-optical trap: A candidate for compact CPT cold atom-clocks

We have demonstrated the experimental realization of a single-beam mini magneto-optical trap of 87Rb atoms, originally designed for a cold atom-clock with coherent population trapping (CPT). Only one beam is used as cooling, trapping and repumping beams rather than the three pairs of orthogonal beams of the standard magneto-optical trap. The core optics, which consists of a modified pyramidal funnel type mirror, a quarter-wave plate and a retroreflect mirror, is installed inside a mini titanium cubic chamber. The vacuum system, rubidium source, magnetic field coils and beam expander are designed in a compact geometry. As many as 1.1 × 10 7 rubidium atoms are cooled and trapped, and thus the mini trap is ready for the implementation of a novel compact coherent population trapping cold atom-clock.