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This study was conducted to develop temperature-dependent postdiapause development models of overwintering larvae of the Asian corn borer, Ostrinia furnacalis Guenée (Lepidoptera: Crambidae), and to evaluate the models’ forecasting accuracy using spring adult emergence data. Overwintering larvae were collected at three different times: 24 February (first), 23 March (second), and 25 April (third), 2005. The developmental periods of each collection colony were measured at eight constant temperatures, and those developmental rates were modeled with linear and nonlinear regression. One linear and three nonlinear models provided good fits of developmental rate to temperature across all colonies (r2 = 0.96–0.99). The distribution of development completion time was modeled with a Weibull equation that fit data from the second (r2 = 0.92) and third (r2 = 0.97) colonies better than the first (r2 = 0.87). A Lactin 2 model based on data from the first colony was statistically the best model to describe the relationship between temperature and the postdiapause development rate of O. furnacalis (r2adj = 0.99). However, validation results based on the field data showed that the Logan 6 model combined with the Weibull model (based on the second colony) was well describing spring adult emergence patterns up to 50% cumulative emergence date. [ABSTRACT FROM AUTHOR]

Fascioliasis, a food-borne trematode zoonosis, is a disease primarily in cattle and sheep and occasionally in humans. Water dropwort (Oenanthe javanica), an aquatic perennial herb, is a common second intermediate host of Fasciola, and the fresh stems and leaves are widely used as a seasoning in the Korean diet. However, no information regarding Fasciola species contamination in water dropwort is available. Here, we collected 500 samples of water dropwort in 3 areas in Korea during February and March 2015, and the water dropwort contamination of Fasciola species was monitored by DNA sequencing analysis of the Fasciola hepatica and Fasciola gigantica specific mitochondrial cytochrome c oxidase subunit 1 (cox1) and nuclear ribosomal internal transcribed spacer 2 (ITS-2). Among the 500 samples assessed, the presence of F. hepatica cox1 and 1TS-2 markers were detected in 2 samples, and F. hepatica contamination was confirmed by sequencing analysis. The nucleotide sequences of cox1 PCR products from the 2 F. hepatica-contaminated samples were 96.5% identical to the F. hepatica cox1 sequences in GenBank, whereas F. gigantica cox1 sequences were 46.8% similar with the sequence detected from the cox1 positive samples. However, F. gigantica cox1 and ITS-2 markers were not detected by PCR in the 500 samples of water dropwort. Collectively, in this survey of the water dropwort contamination with Fasciola species, very low prevalence of F. hepatica contamination was detected in the samples. [ABSTRACT FROM AUTHOR]

Fasciola hepatica is a trematode that causes zoonosis mainly in cattle and sheep and occasionally in humans. Fascioliasis has been reported in Korea; however, determining F. hepatica infection in snails has not been done recently. Thus, using PCR, we evaluated the prevalence of F. hepatica infection in snails at 4 large water-dropwort fields. Among 349 examined snails, F. hepatica-specific internal transcribed space 1 (ITS-1) and/or ITS-2 markers were detected in 12 snails and confirmed using sequence analysis. Morphologically, 213 of 349 collected snails were dextral shelled, which is the same aperture as the lymnaeid snail, the vectorial host for F. hepatica. Among the 12 F. hepatica-infected snails, 6 were known first intermediate hosts in Korea (Lymnaea viridis and L. ollula) and the remaining 6 (Lymnaea sp.) were potentially a new first intermediate host in Korea. It has been shown that the overall prevalence of the snails contaminated with F. hepatica in water-dropwort fields was 3.4%; however, the prevalence varied among the fields. This is the first study to estimate the prevalence of F. hepatica infection using the vectorial capacity of the snails in Korea. [ABSTRACT FROM AUTHOR]

This study investigated the effect of adaptation of Staphylococcus aureus strains to the acidic condition of tomato in response to environmental stresses, such as heat and acid. S. aureus ATCC 13565, ATCC 14458, ATCC 23235, ATCC 27664, and NCCP10826 habituated in tomato extract at 35°C for 24 h were inoculated in tryptic soy broth. The culture suspensions were then subjected to heat challenge or acid challenge at 60°C and pH 3.0, respectively, for 60 min. In addition, transcriptional analysis using quantitative real-time PCR was performed to evaluate the expression level of acid-shock genes, such as clpB, zwf, nuoF, and gnd, from five S. aureus strains after the acid habituation of strains in tomato at 35CC for 15 min and 60 min in comparison with that of the nonhabituated strains. In comparison with the nonhabituated strains, the five tomato-habituated S. aureus strains did not show cross protection to heat, but tomato-habituated S. aureus ATCC 23235 showed acid resistance. In quantitative real-time-PCR analysis, the relative expression levels of acid-shock genes (clpB, zwf, nuoF, and gnd) were increased the most in S. aureus ATCC 23235 after 60 min of tomato habituation, but there was little difference in the expression levels among the five S. aureus strains after 15 min of tomato habituation. These results indicate that the variation of acid resistance of S. aureus is related to the expression of acid-shock genes during acid habituation. [ABSTRACT FROM AUTHOR]

Populations of cotton aphid on Hibiscus syriacus increased rapidly from 17 to 24 May 2007, and then decreased as its predator, the lady beetle Hamonia axyridis, increased in number. There was a 10 day time lag between peak populations of aphids and lady beetles. The infestation of aphids on H. syriacus produced some damage, but H. syriacus recovered soon after the lady beetles arrived. Cotton aphid clones from H. syriacus were transferred to other summer host plants: to five different vegetables on two dates, and to cucumber on three dates. Apart from one case where reproduction occurred on eggplant, most H. syriacus aphid clones did not survive on the vegetables. The cotton aphid on H. syriancus was prey and a food source for H. axyridis and acted to conserve natural enemies. [ABSTRACT FROM AUTHOR]

We investigated the effect of interracial reaction and morphology on the rheological properties of a reactive bilayer polymer system consisting of end-functionalized polystyrene with carboxylic acid (PS-mCOOH) and poly{methyl methacrylate-ran-glycidylmethacrylate) (PMMA-GMA). We found that the complex viscosity (|η*|) of the reactive bilayer was unusually higher than the predicted value from the inverse relationship which holds for nonreactive bilayer, even though the interfacial roughness generated from PMMA-graft-PS copolymers formed in situ from the reaction near the interface was much smaller than the thicknesses of two plates of PS-mCOOH and PMMA-GMA. This indicates that in addition to the effect of the improved mechanical strength or interfacial mixing between chains by the presence of graft copolymers located near the interlace, the roughness of the interface greatly influences |η*| of the reactive bilayer. [ABSTRACT FROM AUTHOR]