Genetic divergence in the ascidian Pyura praeputialis (= Pyura stoloniftra) (Heller, 1878) from mainland Australia and Tasmania

In Australia, the sea squirt is found off the mainland and off the island of Tasmania. The extent of genetic divergence between insular and mainland continental samples was determined by performing a DNA anaysis using PCR--RFLP on the internal transcribed spacer region of ribosomal DNA. The two mainland populations were polymorphic and showed similar type frequencies, but both were significantly different from the Tasmanian population. This was also monomorphic, showing a unique type, absent from the two continental populations. The genetic differentiation could be explained by the lack flow observed between both mainland and Tasmanian populations

Impact of ethanol containing gasoline blends on emissions from a flex-fuel vehicle tested over the Worldwide Harmonized Light duty Test Cycle (WLTC)

AbstractRegulated and unregulated emissions from a Euro 5a flex-fuel vehicle tested with nine different hydrous and anhydrous ethanol containing fuel blends at 23 and −7°C over the World harmonized Light-duty vehicle Test Cycle and the New European Driving Cycle, were investigated at the Vehicle Emission Laboratory at the European Commission Joint Research Centre Ispra, Italy. The experimental results showed no differences on the regulated and unregulated emissions when hydrous ethanol blends were used instead of anhydrous ethanol blends. The use of E85 and E75 blends (gasoline containing 85% and 75% of ethanol, respectively) resulted in a reduction of NOx emissions (30–55%) but increased the emissions of carbon monoxide, methane, carbonyls and ethanol compared to E5, E10 and E15 blends (gasoline containing 5%, 10% and 15% of ethanol, respectively). The increase of the acetaldehyde and ethanol emissions (up to 120% and 350% at 23°C and up to 400% and 390% at −7°C, for acetaldehyde and ethanol, respectively) caused a severe increment of the ozone formation potential. Most of the studied pollutants presented similar emission factors during the tests performed with E10 and E15 blends. The emission factors of most unregulated compounds were lower over the NEDC (with ammonia as an exception) than over the WLTC. However, when taking into consideration only the cold start emissions, emission factors over the WLTC were observed to be higher, or similar, to those obtained over the NEDC. Low ambient temperature caused an increase of the emissions of all studied compounds with all tested blends

Efficacy optimization of plasma-activated water for food sanitization through two reactor design configurations

The chemistry, antimicrobial efficacy and energy consumption of plasma-activated water (PAW) was optimized by altering the discharge frequency, ground-electrode configuration, gas flow rate and initial water conductivity for two reactor configurations, i.e., air pin-to-liquid discharge and air plasma-bubble discharge in water. The ratio of NO2− and NO3− formation was altered to optimise the antimicrobial effects of PAW, tested against two Gram-negative bacteria. An initial solution conductivity of 0.2 S·m−1 and 2000-Hz discharge frequency with the ground electrode positioned inside the pin reactor showed the highest antimicrobial effect resulting in a 3.99 ± 0.13-log10 reduction within 300 s against Escherichia coli and 5.90 ± 0.24-log10 reduction within 240 s for Salmonella Typhimurium. An excellent energy efficiency of reactive oxygen and nitrogen species (RONS) generation of 10.1 ± 0.1 g·kW−1·h−1 was achieved. Industrial relevance: Plasma-activated water (PAW) is deemed as an eco-friendly alternative to chemical disinfection because its bactericidal activity is temporary. Optimizing the design and operation of PAW reactors to achieve high inactivation rates of more than 5-log10 reductions, as demonstrated in this work, will support the industrial application of this technology and the scaleup at industrial level

Comparison of two commercial ELISA kits and magnetic stirrer method for detection of Trichinella spp. in a pig slaughterhouse

ELISA represents a useful rapid method to detect the presence of specific antibodies on serum, plasma or meat juice collected at slaughter, however, false- and positive-results may occur depending on the sensitivity and specificity of the test. In this study we compare two commercial ELISA kits for the detection of specific antibodies against Trichinella spp. with respect to the gold standard method (artificial digestion) in a pig slaughterhouse. A total of 709 Iberian pigs belonging to 79 free-range herds were randomly selected and sampled (five to ten animals/herd) (Win Episcope 2.0; 95% confidence level, 8% accepted error)

Tracing sediment sources in an agriculture and livestock catchment of Argentina through the use of geochemical fingerprints

A mixing modelling approach (CSSIAR v2.00), using Energy Dispersive X Ray Fluorescence (EDXRF) and Total Organic Carbon (TOC) data as fingerprints for sediment sources and sinks, was applied for identifying critical hot spots of erosion in a typical Argentinian agro-ecosystem. The selected study site is the Estancia Grande catchment, covering 1235 hectares, which is located 23 km north east of San Luis (in the centre of Argentina). The studied catchment, which is characterized by highly erodible Haplic Kastanozem soils, is currently being used for agriculture (crop rotation), and livestock (free grazing and feedlots), and some fields are used for growing nut trees (walnuts and almonds) (Figure 1). Further fallow land is found in between the agriculture land and in the upper part of the catchment.Fil: Torres Astorga, Romina Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; ArgentinaFil: Velasco, Ricardo Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; ArgentinaFil: Resch, C.. Organismo Internacional de Energía Atómica ; AustriaFil: Gruber, R.. Organismo Internacional de Energía Atómica ; AustriaFil: Padilla, R.. Organismo Internacional de Energía Atómica ; AustriaFil: Dercon, G.. Organismo Internacional de Energía Atómica ; AustriaFil: Mabit, L.. Organismo Internacional de Energía Atómica ; Austri

Epidemiological tracing of Salmonella enterica serotype Abortusovis from Spanish ovine flocks by PFGE fingerprinting

Salmonella enterica serotype Abortusovis, an ovine host-specific serotype, rare in most countries, is responsible for epidemic abortion episodes in Spain. With the aim of surveillance and detection of the spread of specific clones, 55 Abortusovis isolates collected during 1996-2001 from flocks in 11 provinces, were studied using XbaI-PFGE. Despite the fact that the strains were geographically and spatially related, PFGE demonstrated an epidemiologically acceptable discriminating power, identifying 20 clones (similarity, 52-96%). Clones Sabv6, 1, 5 were disseminated in seven, five and two areas respectively, while another 17 clones appeared in single places. Clones from nearby geographic regions showed a high relatedness (one band of difference in the PFGE profile) Sabv1-2-3, Sabv5-6, Sabv7-8, and Sabv13-14, suggesting a common ancestor. Co-isolation in the same flock (Sabv5-6, Sabv1-3, Sabv1-6) was detected. PFGE surveillance detected the predominance and widespread distribution of clone Sabv6 in 21 out of the 55 Abortusovis serotype episodes studied in Spain.We thank all the Spanish laboratories which sent Abortusovis strains to LNRSSE. This work was supported by a grant from the Instituto de Salud Carlos III (02/0008) and Junta de Andalucía (Investigation Group AGR-149).S

Using the second-order information for reconfigurability analysis and design in the fault tolerant framework

The control reconfigurability measure defines the capability of a control system to allow recovery of performance when faults occur; therefore, it has been intended to be a tool for designing and synthesizing approaches in the fault tolerant control context. Reconfigurability depends on the controllability gramian, also known as the second-order information (SOI) in a broad sense. This paper proposes the assignation, by feedback, of the deterministic SOI in order to set the control reconfigurability of a given linear system. The theory concerned with this assignation is reviewed, then constructive theorems are given for finding constant feedback gains that approximate a required control reconfigurability for ease implementation. Also an unification of the reconfigurability measures proposed in the fault tolerance literature is given. Once the SOI is assigned by feedback, it can be computed online by using an identification method, which uses process input/output data. Results from simulation of the three tanks hydraulic benchmark, show that this approach can provide information about the system performance for fault tolerant purposes, thus online control reconfigurability computation and fault accommodation are considered. The approach presented in the paper gives an alternative for supervision taking into account the reconfigurability assigned by design