Stability of hepatitis E virus at high hydrostatic pressure processing.

Hepatitis E virus (HEV) is the causative agent of acute and chronic hepatitis in humans. The zoonotic HEV genotype 3 is the main genotype in Europe. The foodborne transmission via consumption of meat and meat products prepared from infected pigs or wild boars is considered the major transmission route of this genotype. High hydrostatic pressure processing (HPP) is a technique, which can be used for inactivation of pathogens in food. Here, preparations of a cell culture-adapted HEV genotype 3 strain in phosphate-buffered saline (PBS) were subjected to HPP and the remaining infectivity was titrated in cell culture by counting fluorescent foci of replicating virus. A gradual decrease in infectivity was found by application of 100 to 600 MPa for 2 min. At 20 °C, infectivity reduction of 0.5 log10 at 200 MPa and 1 log10 at 400 MPa were observed. Slightly higher infectivity reduction of 1 log10 at 200 MPa and 2 log10 at 400 MPa were found by application of the pressure at 4 °C. At both temperatures, the virus was nearly completely inactivated (>3.5 log10 infectivity decrease) at 600 MPa; however, low amounts of remaining infectious virus were observed in one of three replicates in both cases. Transmission electron microscopy showed disassembled and distorted particles in the preparations treated with 600 MPa. Time-course experiments at 400 MPa showed a continuous decline of infectivity from 30 s to 10 min, leading to a 2 log10 infectivity decrease at 20 °C and to a 2.5 log10 infectivity decrease at 4 °C for a 10 min pressure application each. Predictive models for inactivation of HEV by HPP were generated on the basis of the generated data. The results show that HPP treatment can reduce HEV infectivity, which is mainly dependent on pressure height and duration of the HPP treatment. Compared to other viruses, HEV appears to be relatively stable against HPP and high pressure/long time combinations have to be applied for significant reduction of infectivity.

Discussing State-of-the-Art Spatial Visualization Techniques Applicable for the Epidemiological Surveillance Data on the Example of Campylobacter spp. in Raw Chicken Meat.

Within the European activities for the 'Monitoring and Collection of Information on Zoonoses', annually EFSA publishes a European report, including information related to the prevalence of Campylobacter spp. in Germany. Spatial epidemiology becomes here a fundamental tool for the generation of these reports, including the representation of prevalence as an essential element. Until now, choropleth maps are the default visualization technique applied in epidemiological monitoring and surveillance reports made by EFSA and German authorities. However, due to its limitations, it seems to be reasonable to explore alternative chart type. Four maps including choropleth, cartogram, graduated symbols and dot-density maps were created to visualize real-world sample data on the prevalence of Campylobacter spp. in raw chicken meat samples in Germany in 2011. In addition, adjacent and coincident maps were created to visualize also the associated uncertainty. As an outcome, we found that there is not a single data visualization technique that encompasses all the necessary features to visualize prevalence data alone or prevalence data together with their associated uncertainty. All the visualization techniques contemplated in this study demonstrated to have both advantages and disadvantages. To determine which visualization technique should be used for future reports, we recommend to create a dialogue between end-users and epidemiologists on the basis of sample data and charts. The final decision should also consider the knowledge and experience of end-users as well as the specific objective to be achieved with the charts.

A strategy to establish Food Safety Model Repositories.

Transferring the knowledge of predictive microbiology into real world food manufacturing applications is still a major challenge for the whole food safety modelling community. To facilitate this process, a strategy for creating open, community driven and web-based predictive microbial model repositories is proposed. These collaborative model resources could significantly improve the transfer of knowledge from research into commercial and governmental applications and also increase efficiency, transparency and usability of predictive models. To demonstrate the feasibility, predictive models of Salmonella in beef previously published in the scientific literature were re-implemented using an open source software tool called PMM-Lab. The models were made publicly available in a Food Safety Model Repository within the OpenML for Predictive Modelling in Food community project. Three different approaches were used to create new models in the model repositories: (1) all information relevant for model re-implementation is available in a scientific publication, (2) model parameters can be imported from tabular parameter collections and (3) models have to be generated from experimental data or primary model parameters. All three approaches were demonstrated in the paper. The sample Food Safety Model Repository is available via: http://sourceforge.net/projects/microbialmodelingexchange/files/models and the PMM-Lab software can be downloaded from http://sourceforge.net/projects/pmmlab/. This work also illustrates that a standardized information exchange format for predictive microbial models, as the key component of this strategy, could be established by adoption of resources from the Systems Biology domain.

DEVELOPMENT OF AN ANNOTATION SCHEME FOR STANDARDIZED DESCRIPTION OF MATHEMATICAL MODELS IN THE FIELD OF PLANT PROTECTION.

Mathematical models on properties and behavior of harmful organisms in the food chain are an increas- ingly relevant approach of the agriculture and food industry. As a consequence, there are many efforts to develop biological models in science, economics and risk assessment nowadays. However, there is a lack of international harmonized standards on model annotation and model formats, which would be neces- sary to set up efficient tools supporting broad model application and information exchange. There are some established standards in the field of systems biology, but there is currently no corresponding provi- sion in the area of plant protection. This work therefore aimed at the development of an annotation scheme using domain-specific metadata. The proposed scheme has been validated in a prototype implementation of a web-database model repository. This prototypic community resource currently contains models on aflatoxin secreting fungal Aspergillus flavus in maize, as these models have a high relevance to food safety and economic impact. Specifically, models describing biological processes of the fungus (growth, Aflatoxin secreting), as well as dose-response- and carry over models were included. Furthermore, phenological models for maize were integrated as well. The developed annotation scheme is based on the well-established data exchange format SBML, which is broadly applied in the field of systems biology. The identified example models were annotated according to the developed scheme and entered into a Web-table (Google Sheets), which was transferred to a web based demonstrator available at https://sites.google.com/site/test782726372685/. By implementation of a software demonstrator it became clear that the proposed annotation scheme can be applied to models on plant pathogens and that broad adoption within the domain could promote communication and application of mathematical models.

Influência de diferentes concentrações dos fitorreguladores ácido 6-benzilaminopurina e ácido naftalenoacético na propagação vegetativa de Malva sylvestris L / Effect of different BAP and NAA concentration on microprapagation of Malva (Malva sylvestris L. )

Malva sylvestris L. (família Malvaceae), conhecida como malva, é uma espécie medicinal nativa da Europa, cultivada no sul do Brasil. A espécie tem propriedade adstringente, suaviza a irritação dos tecidos e reduz inflamações, entre outras características e atributos medicinais. O estudo teve como objetivo verificar a eficiência dos hormônios ANA (ácido naftalenoacético) e BAP (ácido 6-Benzilaminopurina) na propagação vegetativa a partir do estabelecimento in vitro de segmentos nodais. Segmentos nodais obtidos de plantas matrizes mantidas em casa de vegetação foram submetidos à desinfestação e inoculados em meio MS (Murashige e Skoog) com diferentes concentrações e combinações de ANA (ácido naftalenoacético) e BAP (ácido 6-Benzilaminopurina) totalizando oito tratamentos com 60 repetições cada. Os explantes foram mantidos em sala de crescimento e, ao completar sete dias, as plântulas obtidas foram retiradas e avaliadas quanto ao número de folhas, altura total (cm) e massa fresca (g). As plântulas foram fixadas em substrato "Big bio" e transferidas para casa de vegetação com nebulização. Os dados obtidos foram submetidos à Análise de Variância, seguido pelo Teste de Tukey. As plântulas obtidas em meio MS acrescido de 2,0 mg/Lˉ¹ de BAP e de 0,5 mg/Lˉ¹ de ANA foram as que apresentaram maior média nas três variáveis avaliadas, sendo então o mais indicado para a produção de mudas. Em 10 dias foi observado o enraizamento de todas as plântulas transferidas para casa de vegetação. A aclimatização e o enraizamento ex vitro ocorrem em uma única etapa sem a necessidade da utilização de enraizadores. A técnica desenvolvida demonstra a possibilidade de produção de mudas com custos reduzidos, em larga escala, e com a garantia de fornecer mudas aptas para o cultivo em apenas 17 dias

Effect of different BAP and NAA concentrations on malva (Malva sylvestris L.) micropropagation. Malva sylvestris L. (Malvaceae family), known as mallow, is a medicinal species native toEurope, and it is grown in southern Brazil. It has astringent properties and can sooth tissue irritation and reduce inflammations among other medicinal characteristics. The study aimed to verify the efficiency of the hormones NAA (naphthalene acetic acid) and BAP (6-Benzilaminopurine acid) in propagating the species from establishing in vitro nodal segments. Nodal segments obtained from mother plants kept in greenhouses were disinfected and inoculated in MS medium with different concentrations and combinations of BAP and NAA, amounting to 8 processes with 60 repetitions each. The explants were kept in growth rooms, and after seven days the resulting seedling were removed and assessed regarding the number of leaves, total height (cm) and fresh mass (g). Subsequently, the seedling were fixed on the substrate "Big bio" and transferred to greenhouses with nebulization. The data obtained was subjected toVariance Analysis, followed by the Tukey's test. In 10 days,rooting could be observed in all the plantules transferred to the greenhouse. The plantules obtained in MS medium thatreceived 2.0mg/L-1 BAP and 0.5 mg/L-1 NAA were the ones that presented the highest average in the three variables assessed, therefore the most recommended to producing seedlings of this species. The ex vitro acclimatization and rooting occur in a single phase without the need of root promoters. The technique developed shows that it is possible to produce seedlings of this species at reduced costs, in large scale and with the guarantee to supply seedlings that can be planted in only 17 days.

A longitudinal study of the prevalence of voice disorders in children from a rural school division.

In a mass screening of children ages 6-10 in a rural school division, 203 children were identified as showing a voice deviation. One year later a retesting of 178 of these children showed that 39.9% still showed a voice disorder. Four years later 50 of these children were still available in the same school system; 38% of them still showed a voice disorder. Virtually none of these children were referred to the otolaryngologist for an ENT evaluation or to the speech-language pathologist for voice rehabilitation. Results indicate that, for many of these children, the voice disorders do not "clear up" through maturation alone.

Relationship of acoustic parameters and perceptual ratings of esophageal speech.

For 10 male and 10 female esophageal speakers selected acoustic and perceptual dimensions of esophageal speech were investigated to determine the intercorrelations of the following measures: intelligibility, articulation, rate, fundamental frequency, mean relative intensity, and effectiveness. Results indicate that only articulation and effectiveness were significantly correlated with intelligibility, whereas measures of intelligibility, articulation, rate, fundamental frequency, and mean relative intensity were all significantly correlated with effectiveness ratings.