Managing strategies for organochlorine contaminated soils for a safe food production

Background: Organochlorine pesticides such as dieldrin, DDT and others are highly persistant pesticides, which were applied world wide against pests in horticulture, fruit and arable crops. Although they are forbidden since more than thirty years in the European Union (EU), the compounds remain still in soil. Several crops are known to accumulate these pesticides in eatable parts up to critical levels. For instance dieldrin is detected in high economic value crops such as cucumbers (Cucurbitaceae) and in tomatoes (Solanaceae). Besides plant type and climatic conditions, soil properties, e.g. pH and soil organic carbon content influence the pesticide uptake. In particular in labelled food and feed stuff production, such as organic farming according to EU Regulation (EEC) No. 2092/91, consumer expectations in safe, high quality food are extremely high. Since organic farming is prospering – more than 10% of vegetable production is certified organic in Switzerland – the organochlorine residues in organic food stuff have become a major issue for food control authorities. Enquires showed that imported food from EU countries was partly highly contaminated with organochlorine pesticides such as pumpkin seed and oil. Hence, the organochlorine problem in food stuff is expected to occur EU wide

Taxes, Prisons, and CFOs: The Effects of Increased Punishment on Corporate Tax Compliance in Ecuador

This paper takes advantage of a rich firm level data set from Ecuador to analyze the effects of a reform in 2007 that introduced imprisonment for tax evasion and made a firm’s CFO liable for tax-crimes. Our dataset contains actual tax-return and financial-statement information for the universe of corporations in Ecuador from 2003 to 2007. We study the effects of higher punishment both at the intensive and extensive margins. We combine a difference-in-difference-in-difference approach with the DiNardo, Fortin and Lemieux decomposition method. This allows us to estimate the heterogeneous effects of the reform across the distribution of firms. We find that, at the intensive margin the reform led to an average 10% increase in real corporate tax payments. However, positive effects are only found at the right tail of the tax distribution (above the 75th percentile). At the extensive margin, the probability of entry into the tax-net increased, but most of the firms that entered the tax net claimed zero taxes.Tax evasion, corporate tax compliance, tax reform, developing country, punishment, Ecuador

TwitFace

The TwitFace program provides a convenient and efficient tool for Twitter and Facebook users. The central purpose of this project is to create a program that is able to communicate with both the Twitter and Facebook API’s, thus allowing the user to post an identical status simultaneously. The program will require the user’s login information for both accounts and will prompt the user to enter a status to share. The user will also have the option to share a pre-generated post from a generic list of options

How Perturbation Strength Shapes the Global Structure of TSP Fitness Landscapes

Local optima networks are a valuable tool used to analyse and visualise the global structure of combinatorial search spaces; in particular, the existence and distribution of multiple funnels in the landscape. We extract and analyse the networks induced by Chained-LK, a powerful iterated local search for the TSP, on a large set of randomly generated (Uniform and Clustered) instances. Results indicate that increasing the perturbation strength employed by Chained-LK modifies the landscape's global structure, with the effect being markedly different for the two classes of instances. Our quantitative analysis shows that several funnel metrics have stronger correlations with Chained-LK success rate than the number of local optima, indicating that global structure clearly impacts search performance

Evaluation of enhanced haemolysis agar for detection of Listeria spp. and L. monocytogenes from production lines of fresh to cold-smoked fish

Enhanced haemolysis agar (EHA) was compared to the two conventional Listeria isolation agars Oxford and PALCAM for its ability to detect Listeria spp. from production lines of fresh to cold-smoked fish. The ability of EHA for distinguishing L. monocytogenes colonies from other Listeria spp. was also evaluated. A total of 243 fish and environmental samples were analysed. Overall, 42 samples were found to contain Listeria spp. Only 34 samples were positive simultaneously by the three plating media. Two samples considered to be negative by the two conventional agars were found to be positive after isolation on EHA. All three selective agars were shown to be less effective in recovering Listeria spp. after primary enrichment in half-Fraser broth, compared to secondary enrichment in Fraser broth after 24 and 48 h. From 79 Listeria but presumptive negative L. monocytogenes colonies, EHA identified correctly 76 Listeria spp. and presented three false-negative results_three colonies further identified as L. monocytogenes but showing no noticeable haemolysis on EHA. Twenty-three of the thirty-three L. monocytogenes presumptive positive colonies, were confirmed positive and ten were identified as L. seeligeri. Despite its ability of distinguishing L. monocytogenes from the other Listeria spp., unless it is produced as a commercial medium, EHA cannot be an alternative to time-consuming classical identification because the preparation of this medium is both time and labour intensive

Evaluation of mini-VIDAS rapid test for detection of Listeria monocytogenes from production lines of fresh to cold-smoked fish

This study was conducted to evaluate the efficacy of the mini-VIDAS Listeria monocytogenes (LMO) system (BioMe´rieux Vitek, Inc., Missouri, USA) for detection of L. monocytogenes in environmental and fish samples from three Portuguese cold-smoking plants and from their fresh fish suppliers. Mini-VIDAS-LMO is a fully automated system that uses fluorescent ELFA (Enzyme Linked Fluorescent Assay) technology for detection of Listeria monocytogenes antigens in food. It can be a rapid screening method alternative to time consuming classical isolation and identification. Two hundred and ninety five samples were tested in mini-VIDAS-LMO and in parallel by the ISO 11290-1 traditional protocol. The mini-VIDAS-LMO detected 8 of the 11 confirmed positive samples and presented 11 false positive results. The specificity of the mini-VIDASLMO found in this experiment was 0.96 and the sensitivity 0.7

Mutation position and type of substitution in the β-subunit of the RNA polymerase influence in-vitro activity of rifamycins in rifampicin-resistant Mycobacterium tuberculosis

Quantitative susceptibility testing for rifampicin, rifabutin and rifapentine of 36 Mycobacterium tuberculosis isolates with known sequences for the gene encoding for the RNA polymerase β-subunit (rpoB)revealed that both mutation position and type of amino acid substitution influence the in-vitro activity of rifamycins in rifampicin-resistant strain