The current and future potential geographic range of West Indian fruit fly,Anastrepha obliqua （Diptera： Tephritidae）

The West Indian fruit fly, Anastrepha obliqua （Macquart）, is one of the most important pests throughout the Americas. CLIMEX 3.0 and ArcGIS 9.3 were used to model the current and future potential geographical distribution of this pest. Under current climatic conditions, A. obliqua is predicted to be able to establish throughout much of the tropics and subtropics, including not only North and South America, where it has been reported, but also southern Asia, northeastern Australia and Sub-Saharan Africa. The main factors limiting the pest＇s range expansion may be cold stress. Climate change expands the potential distribution of A. obliqua poleward as cold stress boundaries recede, but the predicted distribution in northwestern Australia and northern parts of Sub-Saharan Africa will decrease because of heat stress. Considering the widely suitable range for A. obliqua globally and in China, enhanced quarantine and monitoring measures should be implemented in areas that are projected to be suitable for the establishment of the pest under current and future climatic conditions.     

Estimation of Cellobiohydrolase I Activity by Numerical Differentiation of Dynamic Ultraviolet Spectroscopy

1,4-β-D-glucan cellobiohydrolase I (CBH I),p-nitrophenyl β-D-cellobioside,p-nitrophenol andcellobiose show distinct ultraviolet spectra,allowing the design of an assay to track the dynamic process ofp-nitrophenyl β-D-cellobioside hydrolysis by CBH I.Based on the linear relationship between p-nitrophenolformation in the hydrolysate and its first derivative absorption Curve of AUC340_400_(nm)(area under the curve),a new sensitive assay for the determination of CBH I activity was developed.The dynamic parameters ofcatalysis reaction,such as Vm and k_(cat),can all be derived from this result.The influence of β-glucosidase andendoglucanase in crude enzyme sample on the assay was discussed in detail.This approach is useful foraccurate determination of the activity of CBHs.     

Genetic and environmental sources of covariance among internal reproductive traits in the yellow dung fly

Substantial inter- and intraspecific variation is found in reproductive traits, but the evolutionary implications of this variation remain unclear. One hypothesis is that natural selection favours female reproductive morphology that allows females to control mating and fertilization and that diverse male reproductive traits arise as counter adaptations to subvert this control. Such co-evolution predicts the establishment of genetic correlations between male and female reproductive traits that closely interact during mating. Therefore, we measured phenotypic and genetic correlations between male and female reproductive tract characteristics in the yellow dung fly, Scathophaga stercoraria (Diptera: Scathophagidae), using a nested half-sib breeding experiment. We found significant heritabilities for the size of most reproductive tract traits investigated in both females (spermathecae and their ducts, accessory glands and their ducts) and males (testis size but not sperm length). Within the sexes, phenotypic and genetic correlations were mostly nil or positive, suggesting functional integration of or condition-dependent investment in internal reproductive traits. Negative intrasexual genetic correlations, potentially suggestive of resource allocation trade-offs, were not evident. Intersexual genetic correlations were mostly positive, reflecting expected allometries between male and female morphologies. Most interestingly, testis size correlated positively with female accessory gland size and duct length, potentially indicative of a co-evolutionary arms race. We discuss these and alternative explanations for these patterns of genetic covariance.     

Research of the Holiday kind: Tabulating Ingestion of Mocha Solution (TIMS): a longitudinal prospective cohort study

The annual "Roll Up the Rim to Win" contest at Tim Hortons restaurants provides customers the opportunity to win prizes. This study investigated win ratios, prize types and patterns of coffee consumption.     

The Heritability Theory of Heterosis and Its Meaning for Global Agriculture

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Micronucleus formation in lymphocytes of children from the vicinity of Chernobyl after <Superscript>131</Superscript>I therapy

After the Chernobyl accident a statistically significant increase in the number of children with thyroid tumours was observed. In this study 166 children with and 75 without thyroid tumours were analysed for micronucleus formation in peripheral blood lymphocytes using the cytochalasin B approach. The following factors did not significantly affect micronucleus formation: gender, age at the time of the first ¹³¹I treatment, tumour stage, tumour type, or metastases; a statistically significant increase in the number of micronuclei, however, was observed for the residents of Gomel compared to other locations, such as Brest, Grodno, and Minsk. The children with tumours received ¹³¹I treatment after surgical resection of the tumours. This gave us the opportunity to systematically follow the effect of ¹³¹I on micronucleus formation. A marked increase was observed 5 days after the ¹³¹I treatment followed by a decrease within a 4–7 months interval up to the next application, but the pre-treatment levels were not achieved. Up to 10 therapy cycles were followed each including an analysis of micronucleus formation before and 5 days after ¹³¹I application. The response of the children was characterised by clear individual differences and the increase/decrease pattern of micronucleus frequencies induced by iodine-131 was correlated with a decrease/increase pattern in the number of lymphocytes.     

Sexual selection on morphological and physiological traits and fluctuating asymmetry in the yellow dung fly

Previous univariate studies of the yellow dung fly (Scathophaga stercoraria) have demonstrated strong sexual selection, in terms of mating success, on male size (estimated as hind tibia length). To identify specific target(s) of selection on body size and possible conflicting selection pressures on particular body parts, two multivariate field studies of sexual selection were conducted. In one study using point samples from three populations, we assessed several morphological traits, including genital traits and measures of fluctuating asymmetry (FA) of all paired traits. There was sexual selection for large male size in general, confirming previous, univariate studies. With the possible exception of thorax width, which was selected in the opposite direction, no main target of selection was identified, as most morphological traits were highly correlated. There was no detectable sexual selection on the male external genital structures assessed. In a second study using multiple samples from one population, we included physiological measures of energy reserves (lipids, glucose and glycogen) known to affect mating success, in addition to trait size and FA of wings and legs. Inclusion of physiological traits is rare in phenomenological studies of selection. This study again confirmed the mating advantage of large males, and additionally showed independent positive influences of lipid and glucose but not glycogen levels. FA in paired traits generally did not affect male mating success, but was negatively correlated with energy reserves. Our study suggests that inclusion of physiological measures and genital traits in phenomenological studies of selection would be fruitful in other species.