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Tomatoes (Solanum lycopersicum) are one of the most commonly consumed fruits worldwide. The fruit can become contaminated with Salmonella and Listeria monocytogenes at various stages of the production and supply chain, and these pathogens may survive under various storage conditions. The effects of relative humidity, temperature, and duration of storage on the attachment and survival of both pathogens on the surface of tomatoes were investigated. Fresh whole Roma tomatoes were inoculated with a cocktail of Salmonella or L. monocytogenes strains and stored at 5, 12, 25, 30, or 35°C for up to 10 days. Every day during storage, relative humidity and temperature were measured and tomatoes were removed to enumerate pathogens cells that were loosely attached (LA; cells were detached from the tomato surface by rinsing) and strongly attached (SA; sonication was required to detach cells from the tomato surface). The attachment strength (SR) was calculated to express the proportion of surviving SA cells on the tomato surface. The initial levels of Salmonella and L. monocytogenes on the tomato surface after inoculation were 6.6 and 6.5 log CFU per tomato for LA cells and 5.1 and 5.6 log CFU per tomato for SA cells, respectively. For both pathogens, the LA levels were higher (P < 0.05) than the SA levels. The LA and SA levels differed significantly as a function of temperature, relative humidity, and duration of storage. The SR for Salmonella was affected by storage time but not temperature, whereas the SR for L. monocytogenes was affected by storage time and temperature and relative humidity (P < 0.05). An understanding of the attachment and survival of Salmonella and L. monocytogenes on tomatoes stored under various temperature conditions may be useful for preventing or reducing the establishment of pathogens and for designing improved decontamination methods. [ABSTRACT FROM AUTHOR]

We have shown the efficacies of translationally fused gene (cry1Ab1B) under the control of maize ubiquitin promoter and hybrid Bt gene (cry1A/cry1Ac) driven by rice Actin-1 promoter against the yellow stem borer (Scirpophaga incertulas Walker, YSB) insect in rice (Oryza sativa L.). The integration, expression, and functionality of the transgenes were confirmed by Southern, western, and insect bioassay. The bioassay results correlated with the molecular data. The amount of Bt protein (within the range of 0.8-1.3% of the total soluble protein) in the transgenics was sufficient to cause 100% mortality of the neonate larvae of YSB within 1 wk of infestation. The transgenic plants expressing the foreign Bt protein were normal in phenotype with as good seed setting as the nontransgenic control plants., RICE, the most important cereal grain crop worldwide, is cultivated on 5.9 million hectares spanning 80% of the arable land of Vietnam and providing 80% of the carbohydrate and 40% [...]

The cry genes of Bacillus thuringiensis can be screened and isolated using the exclusive polymerase chain reaction (E-PCR) method. It can also be used to discover new cry genes by using the same initial set of primers. E-PCR is a two-step technique that can be used to detect unknown genetic sequences. The first step uses three primers to identify previously known cryI genes. The second step uses the same three primers to identify unknown cryI genes by excluding the known sequences.

The larvae of a laboratory colony of the European sunflower moth Homoeosoma nebulella contain five subspecies (subspp.) of Bacillus thuringiensis that produce different insecticidal proteins. The subspp. thuringiensis produces spherical crystals, thompsoni produces pyramidal crystals while the other subspp. produce bipyramidal crystals. The thuringiensis, aizawai and kurstaki subspp. are toxic to H. nebulella and are potential agents for use against this insect.

Retinoblastoma represents 3% of cancers in children under fifteen years of age. The standard paediatric treatment for saving the affected eye is supraselective intra-arterial chemotherapy performed in interventional rooms. In order to address the radiation toxicity due to the angiography, the aim of this study was to determine the typical dose value corresponding to the procedure, estimate the paediatric patients' eye lens dose and study the relationship between dose indicators and dose to the lens. An automatic dose management software was installed in two interventional rooms to obtain the distribution of the dose indicators kerma-area product and reference-point air kerma, getting a typical value 16 Gy·cm2 and 130 mGy, respectively (n = 35). The eye lens dose estimates were obtained with photoluminescent dosimeters placed on the patient's eyelids. In the left eye, the entrance surface air kerma was 44.23 ± 2.66 mGy, and 12.72 ± 0.89 mGy in the right eye (n = 10). There was a positive correlation between dose to the lens per procedure and dose indicators, with R2 > 0.65 for both eyes. Based on this information, the threshold for the onset of radiation-induce cataracts (500 mGy) will be exceeded if the treatment is performed for more than 8 sessions. [ABSTRACT FROM AUTHOR]

Insecticidal Cry, or Bt, proteins are produced by the soil-endemic bacterium, Bacillus thuringiensis and some genetically modified crops. Their environmental fate depends on interactions with soil. Little is known about the toxicity of adsorbed proteins and the change in toxicity over time. We incubated Cry1Ac and Cry2A in contrasting soils subjected to different treatments to inhibit microbial activity. The toxin was chemically extracted and immunoassayed. Manduca sexta was the target insect for biotests. Extractable toxin decreased during incubation for up to four weeks. Toxicity of Cry1Ac was maintained in the adsorbed state, but lost after 2 weeks incubation at 25 °C. The decline in extractable protein and toxicity were much slower at 4 °C with no significant effect of soil sterilization. The major driving force for decline may be time-dependent fixation of adsorbed protein, leading to a decrease in the extraction yield in vitro , paralleled by decreasing solubilisation in the larval gut. [ABSTRACT FROM AUTHOR]

This paper compares the responses of employment and GDP Spanish growth to a permanent unitary shock in different types of transport capital stock, with those estimated in the literature. The theoretical model used to estimate the step response functions is the multiple equations dynamic model proposed by Flores et al.. (1998) adapted to this particular problem. Results suggest that: (1) The standard single equation static methodology underestimates the elasticity of the capital stock with respect to output, due to the existence of feedback relationships among transport capital stock and output. (2) The exclusion of the remaining net capital stock from the model, when dealing with a particular type of transport capital stock, might lead to biases in the estimation of the responses. [ABSTRACT FROM AUTHOR]