The European corn borer, Ostrinia nubilalis [Lepidoptera : Pyralidae] : a potential pest of potatoes growth on Prince Edward Island

L'influence de la pyrale du maïs, Ostrinia nubilalis (Lepidoptera: Pyralidae) sur le rendement des pommes déterre (Solanum tuberosum 'Russet Burbank') a été évaluée à deux localités de l'île du Prince Edouard en 1989 et 1990. À Summerside, le nombre moyen de larves par tige n'a pas excédé 0,19 pour ces deux années, et aucune différence significative de rendement n'a été trouvée entre les parcelles-témoins non traitées et les parcelles protégées avec le Bacillus thuringiensisvar. kurstaki (B.t.k.). À Tryon en 1989, une moyenne saisonnière de 1,16 larves par tige a réduit les rendements totaux et vendables de 7,5 et 8,8% respectivement, par rapport aux parcelles protégées par le B.t.k. Une tendance similaire quoique non significative a été observée en 1990 à ce même endroit. Le niveau plus élevé de dommages causés par la pyrale du maïs aux pommes de terre cultivées à l'île du Prince Edouard, par rapport aux cultures de régions plus au sud, peut être dû au plus long intervalle d'attaque. À l'île du Prince Edouard, le seuil d'action pour la pyrale du maïs sur les pommes déterre semble se situer entre 0,11 et 0,30 masse d'oeufs par tige.The effects of the European corn borer, Ostrinia nubilalis [Lepidoptera: Pyralidae], on yield of 'Russet Burbank' potatoes (Solanum tuberosum) was investigated at two sites in Prince-Edward-Island in 1989 and 1990. At Summerside, the mean number of larvae per stalk did not exceed 0.19 in either year, and no significant differences in yield were found between untreated plots (check) and plots protected with Bacillus thuringiensis var. kurstaki (B.t.k.). At Tryon in 1989, a seasonal average of 1.16 larvae per stalk reduced total and marketable yields by 7.5% and 8.8%, respectively, compared to plots protected with B.t.k. A similar but not statistically significant trend was observed in 1990 at this site. The higher degree of damage by the European corn borer to potatoes grown on P.E.I., relative to crops grown in more southernly locations, may be due to the longer interval of attack. On P.E.I., the action threshold for the European corn borer on potatoes appears to be between 0.11 and 0.30 egg masses per stalk

Comparison of three management schemes for Colorado potato beetle on early-season potatoes in Prince Edward Island

Les aspects économiques de la lutte au doryphore de la pomme de terre, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae) sur la pomme de terre (Solanum tuberosum) à l'aide de diverses stratégies ont été étudiés à quatre localités de l'île du Prince-Édouard en 1989. Trois traitements ont été essayés à chaque endroit: 1) une parcelle-témoin non traitée; 2) l'application du Bacillus thuringiensis var. tenebrionis ou de roténone après l'atteinte d'un seuil de 0,5 équivalent de doryphore de la pomme de terre (EDPT) par tige (1 EDPT = 1 adulte du printemps, 8 larves de premier ou second stade, 3 larves de troisième ou quatrième stade ou 1,6 adultes de l'été) ; 3) l'application d'insecticides selon le programme régulier de pulvérisation des producteurs. À une des localités, le rendement en tubercules des parcelles gérées avec le seuil de 0,5 EDPT par tige a été similaire à celui obtenu des parcelles pour lesquelles le producteur maintenait son programme régulier de pulvérisation, mais trois applications d'insecticides en moins ont été utilisées dans le premier cas. Aux autres localités pour lesquelles la densité de doryphores de la pomme de terre n'a pas excédé le seuil de traitement, le rendement en tubercules a été similaire à celui des autres parcelles des producteurs. Ces résultats indiquent qu'il y a eu des applications superflues d'insecticides par les producteurs.The economics of managing the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae) on potatoes (Solarium tuberosum) with different strategies was tested at four sites on Prince-Edward-Island in 1989. Three treatments were tested at each site: 1) an untreated check, 2) an application of Bacillus thuringiensis var. tenebrionis or rotenone after a threshold of 0.5 Colorado Potato Beetle Equivalents (CPBE) per stalk was reached ( 1 CPBE = 1 spring adult, 8 first- or second- instar larvae, 3 third- or fourth- instar larvae, or 1.6 summer adults), and 3) applications of insecticide according to the grower's normal spray schedule. At one site, tuber yield of plots managed with the 0.5 CPBE-per-stalk threshold was similar to that of plots where the grower maintained his normal spray schedule, but three fewer applications of insecticides were needed in the former. At the remaining sites, where the density of Colorado potato beetles did not exceed the threshold, tuber yield was similar to that of the grower's plots. This suggests that there were needless applications of insecticides by the growers

The location of egg masses of Ostrinia nubilalis [Lepidoptera : Pyralidae] on potato plants

La position des masses d'oeufs de la pyrale du maïs, Ostrinia nubilalis, a été étudiée sur des pommes de terre (Solanum tuberosum) 'Russet Burbank' cultivées à l'île-du-Prince-Édouard (Canada) de 1990 à 1992. La position sur la plante de 315 masses d'oeufs a été caractérisée par l'examen d'environ 3700 plantes. Dans le deux tiers inférieur des plantes se retrouvaient 92 % des masses d'oeufs, tandis que 95 % des masses d'oeufs se localisaient sur la face inférieure des folioles et sur les tiges. Dans l'ensemble, 88 % des masses d'oeufs se retrouvaient dans le deux tiers inférieur des plantes, à la fois sur les tiges et sur la face inférieure des folioles. La période d'échantillonnage pourra être optimisée si les personnes qui effectuent le dépistage concentrent leurs efforts seulement sur le deux tiers inférieur des tiges, lequel représente seulement 3,7 % de la surface totale de la fane mais contient 50 % des masses d'oeufs.The location of egg masses of the European corn borer, Ostrinia nubilalis, was studied on potatoes (Solanum tuberosum) “Russet Burbank” grown on Prince-Edward-Island, Canada, from 1990 to 1992. The within-plant positions of 315 egg masses were characterized by the examination of approximately 3700 plants. Ninety-two percent of the egg masses were found on the bottom two-thirds of the plants and 95% were found on the underside of the leaflets and on the stalks. In total, 88% of the egg masses were found on the bottom two-thirds of the plants on both the stalks and the underside of the leaflets. Sampling time can be optimized if the people engaged in scouting programs concentrate their efforts on the bottom two-thirds of the stalks alone, which represents only 3.7% of the total surface area of the haulm but contains 50% of the egg masses

Opacity calculation for target physics using the ABAKO/RAPCAL code

Radiative properties of hot dense plasmas remain a subject of current interest since they play an important role in inertial confinement fusion (ICF) research, as well as in studies on stellar physics. In particular, the understanding of ICF plasmas requires emissivities and opacities for both hydro-simulations and diagnostics. Nevertheless, the accurate calculation of these properties is still an open question and continuous efforts are being made to develop new models and numerical codes that can facilitate the evaluation of such properties. In this work the set of atomic models ABAKO/RAPCAL is presented, as well as a series of results for carbon and aluminum to show its capability for modeling the population kinetics of plasmas in both LTE and NLTE regimes. Also, the spectroscopic diagnostics of a laser-produced aluminum plasma using ABAKO/RAPCAL is discussed. Additionally, as an interesting application of these codes, fitting analytical formulas for Rosseland and Planck mean opacities for carbon plasmas are reported. These formulas are useful as input data in hydrodynamic simulation of targets where the computation task is so hard that in line computation with sophisticated opacity codes is prohibitive

Modification and characterisation of material hydrophobicity for surface acoustic wave driven microfluidics

Surface acoustic waves (SAW) generated in a piezoelectric substrate may be used to manipulate micro-scale droplets of liquid in a digital microfluidic system for lab-on-a-chip applications. The wettability of the surface over which a droplet is driven determines the ease and speed with which the droplet is propelled. This provides the opportunity to achieve fine control of SAW driven droplets simply by patterning of the surface into areas with different levels of wettability. This paper evaluates a number of different materials and surface preparation techniques and assesses their manufacturability and efficacy for this application. Test structures have been designed and developed to help optimise a fabrication process using the biocompatible polymer Parylene. Early results obtained using airflow as a driving force show that it is possible to manipulate droplets through direction changes of up to 60°. Additional work has been done using surface acoustic waves as the driving force to determine the extent to which droplets can be guided to desired locations

Disparate associations of a functional promoter polymorphism in PCK1 with carotid wall ultrasound traits

Background and Purpose - Cytosolic phosphoenolpyruvate carboxykinase (PEPCK; EC 4.1.1.32), encoded by PCK1, catalyzes the first committed step in gluconeogenesis. We previously showed that a -232C\u3eG promoter polymorphism within a cis-acting element required for basal and cAMP-mediated PCK1 gene transcription results in loss of negative regulation by insulin, contributing to worsened metabolic control in the context of insulin resistance. We hypothesized that this polymorphism would be associated with carotid atherosclerosis in a sample of 150 aboriginal Canadians. Methods - Dependent variables were 2 distinct carotid traits, namely intima-media thickness (IMT) assessed using B-mode ultrasound and total carotid plaque volume (TPV) assessed using 3D ultrasound. Results - Multivariate analysis showed significant but opposite associations of PCK1 genotype with these traits. Specifically, subjects with the PCK1-232G/G genotype had more carotid IMT (0.80±0.02 versus 0.73±0.03 mm; P=0.007) but less TPV (0.10±0.09 versus 0.38±0.13; P=0.03) than subjects with other genotypes. Conclusions - The findings connect the key enzyme in gluconeogenesis with atherosclerosis. The meaning of the opposing associations of PCK1 genotype with IMT and TPV is unclear; more work is required to confirm whether these might be distinct quantitative traits with different biological determinants. © 2005 American Heart Association, Inc

Genetic variation in PPARG encoding peroxisome proliferator-activated receptor γ associated with carotid atherosclerosis

Background and Purpose-Peroxisome proliferator-activated receptor γ is a crucial molecule in atherogenesis because it is associated with metabolic risk factors such as obesity and diabetes and also plays a key role in subcellular metabolism of arterial wall macrophage foam cells. Genetic variation in PPARG has been associated with metabolic and cardiovascular end points. Methods-We investigated the relationship between 2 common PPARG polymorphisms, namely P12A and c.1431C\u3eT, and carotid atherosclerosis in a sample of 161 Canadian aboriginal people. Dependent variables were carotid intima media thickness (IMT), assessed using B-mode ultrasonography, and total carotid plaque volume (TPV), assessed using 3D ultrasound. Results-Using multivariate analysis, we found that subjects with ≥ 1 PPARG A12 allele had less carotid IMT than others (0.72±0.03 versus 0.80±0.02 mm; P=0.0045), with no between-genotype difference in TPV. In contrast, subjects with the PPARG c.1431T allele had greater TPV than others (124±18.4 versus 65.1±23.7 mm3; P=0.0079), with no between-genotype difference in IMT. Conclusions-The findings show an association between PPARG genotypes and carotid arterial phenotypes, and further reflect the prevailing view that the PPARG A12 allele protects against deleterious phenotypes. Also, whereas IMT and TPV are somewhat correlated with each other, they might also represent distinct traits with discrete determinants representing different stages of atherogenesis

Response, relaxation and transport in unconventional superconductors

We investigate the collision-limited electronic Raman response and the attenuation of ultrasound in spin-singlet d-wave superconductors at low temperatures. The dominating elastic collisions are treated within a t-matrix approximation, which combines the description of weak (Born) and strong (unitary) impurity scattering. In the long wavelength limit a two-fluid description of both response and transport emerges. Collisions are here seen to exclusively dominate the relaxational dynamics of the (Bogoliubov) quasiparticle system and the analysis allows for a clear connection of response and transport phenomena. When applied to quasi-2-d superconductors like the cuprates, it turns out that the transport parameter associated with the Raman scattering intensity for B1g and B2g photon polarization is closely related to the corresponding components of the shear viscosity tensor, which dominates the attenuation of ultrasound. At low temperatures we present analytic solutions of the transport equations, resulting in a non-power-law behavior of the transport parameters on temperature.Comment: 22 pages, 3 figure

Mobilisation of arsenic from bauxite residue (red mud) affected soils: effect of pH and redox conditions

The tailings dam breach at the Ajka alumina plant, western Hungary in 2010 introduced ~1 million m3 of red mud suspension into the surrounding area. Red mud (fine fraction bauxite residue) has a characteristically alkaline pH and contains several potentially toxic elements, including arsenic. Aerobic and anaerobic batch experiments were prepared using soils from near Ajka in order to investigate the effects of red mud addition on soil biogeochemistry and arsenic mobility in soil–water experiments representative of land affected by the red mud spill. XAS analysis showed that As was present in the red mud as As(V) in the form of arsenate. The remobilisation of red mud associated arsenate was highly pH dependent and the addition of phosphate to red mud suspensions greatly enhanced As release to solution. In aerobic batch experiments, where red mud was mixed with soils, As release to solution was highly dependent on pH. Carbonation of these alkaline solutions by dissolution of atmospheric CO2 reduced pH, which resulted in a decrease of aqueous As concentrations over time. However, this did not result in complete removal of aqueous As in any of the experiments. Carbonation did not occur in anaerobic experiments and pH remained high. Aqueous As concentrations initially increased in all the anaerobic red mud amended experiments, and then remained relatively constant as the systems became more reducing, both XANES and HPLC–ICP-MS showed that no As reduction processes occurred and that only As(V) species were present. These experiments show that there is the potential for increased As mobility in soil–water systems affected by red mud addition under both aerobic and anaerobic conditions

A weakly stable algorithm for general Toeplitz systems

We show that a fast algorithm for the QR factorization of a Toeplitz or Hankel matrix A is weakly stable in the sense that R^T.R is close to A^T.A. Thus, when the algorithm is used to solve the semi-normal equations R^T.Rx = A^Tb, we obtain a weakly stable method for the solution of a nonsingular Toeplitz or Hankel linear system Ax = b. The algorithm also applies to the solution of the full-rank Toeplitz or Hankel least squares problem.Comment: 17 pages. An old Technical Report with postscript added. For further details, see http://wwwmaths.anu.edu.au/~brent/pub/pub143.htm