Search results for "Rete"
showing 10 items of 3470 documents
Occurrence of retene and resin acids in sediments and fish bile from a lake receiving pulp and paper mill effluents
1999
Retene (7-isopropyl−1-methylphenanthrene) is a dialkyl-substituted PAH derived thermally and microbially from dehydroabietic acid. We have analyzed for retene and several resin acids in sediments at five depths at several sites in a lake receiving effluents from three pulp and paper mills, and two upstream reference sites. The highest concentration of retene was 1,600 μg/g dry weight (11,700 μg/g organic carbon [OC]) and of total resin acids was 1,500 μg/g dry weight (9,300 μg/g OC). Twelve kilometers downstream from the point of bleached-kraft mill effluent (BKME) discharge, the concentration of retene at a depth of 5 to 10 cm was 16 μg/g dry weight (650 μg/g OC) and of resin acids was 139…
Sediment-associated retene bioavailability of sediment-associated retene to an oligochaete wormlumbriculus variegatus
2001
The bioavailability of retene spiked to two sediment concentrations (50 and 200 µg/g dry weight) was measured in long-term (28-day) bioaccumulation tests performed on the oligochaeteLumbriculus variegatus Muller. Three sediment organic carbon (SOC) concentrations (1.1, 3.0, 23.0% of dry weight) were used. Growth and reproduction, used as endpoints, indicated that retene was chronically nontoxic at the concentrations employed. Retene was clearly bioavailable, but bioaccumulated about 100 times less in the SOC-rich (23.0%) sediment than in the other two (SOC <3.0%). At the lower retene concentration, retene in the worms was undetectable in the high-SOC sediment. Based on final retene present …
Clarkson-McCarthy inequalities with unitary and isometry orbits
2020
Abstract A refinement of a trace inequality of McCarthy establishing the uniform convexity of the Schatten p-classes for p > 2 is proved: if A , B are two n-by-n matrices, then there exists some pair of n-by-n unitary matrices U , V such that U | A + B 2 | p U ⁎ + V | A − B 2 | p V ⁎ ≤ | A | p + | B | p 2 . A similar statement holds for compact Hilbert space operators. Another improvement of McCarthy's inequality is given via the new operator parallelogramm law, | A + B | 2 ⊕ | A − B | 2 = U 0 ( | A | 2 + | B | 2 ) U 0 ⁎ + V 0 ( | A | 2 + | B | 2 ) V 0 ⁎ for some pair of 2n-by-n isometry matrices U 0 , V 0 .
Retrospection in interpreting and translation: explaining the process?
2014
Retrospection is one of the few research methods equally suitable for studying the processes involved in both translation and interpreting. At the first workshop on research methods in process-oriented research (Graz 2009), we presented the results of a pilot study of retrospection as a research method, published as Englund Dimitrova & Tiselius (2009). The study involved data from two groups (15 years of professional experience vs. no professional experience), each with 3+3 subjects (interpreter subjects vs. translator subjects, all with Swedish as their L1). The source text was a 10-minute plenary speech in English from the European Parliament, interpreted simultaneously into Swedish. …
Measuring job stress in transportation workers: psychometric properties, convergent validity and reliability of the ERI and JCQ among professional dr…
2021
Abstract Background The accumulated evidence has shown how professional drivers are, in psychosocial terms, among the most vulnerable workforces, and how their crashes (some of them preceded by stressful working conditions) constitute both an occupational and public health concern. However, there is a clear lack of validated tools for measuring stress and other key hazardous issues affecting transport workers, and most of the existing ones, frequently generic, do not fully consider the specific features that properly describe the work environment of professional driving. This study assessed the psychometric properties, convergent validity and consistency of two measures used for researching…
Traumi del rene, della vescica, delle vie urinarie
2020
Classificazione dei traumi del rene e delle vie urinarie e algoritmi diagnostico-terapeutici
A branch-price-and-cut algorithm for the capacitated multiple vehicle traveling purchaser problem with unitary demand
2021
Abstract The multiple vehicle traveling purchaser problem (MVTPP) consists of simultaneously selecting suppliers and routing a fleet of homogeneous vehicles to purchase different products at the selected suppliers so that all product demands are fulfilled and traveling and purchasing costs are minimized. We consider variants of the MVTPP in which the capacity of the vehicles can become binding and the demand for each product is one unit. Corresponding solution algorithms from the literature are either branch-and-cut or branch-and-price algorithms, where in the latter case the route-generation subproblem is solved on an expanded graph by applying standard dynamic-programming techniques. Our …
An Investigation of the Robustness in the Travelling Salesman Problem Routes Using Special Structured Matrices
2020
In this study, the robustness of the Travelling Salesman Problem (TSP) routes is investigated by recognising the special combinatorial structures of Kalmanson matrices. A recognition algorithm encompassing three procedures based on combinatorial and linear programming (LP) is developed and executed on several randomly generated instances. These procedures produce three lower bounds which provide guarantees on the optimality of the solutions. Computational experiments show that the proposed LP-based procedure performs efficiently well across all problem dimensions and provides the best lower bounds to the TSP. This is supported by an average deviation of less than 7% between the TSP tour len…
Visualization of Large Terrain Using Non-restricted Quadtree Triangulations
2004
This paper presents a set of new techniques oriented towards the real-time visualization of large terrains. These techniques are mainly focused on semi-regular triangulations of non-restricted quadtree terrain representations. Despite the fact that the paper shows that triangulations based on non-restricted quadtrees are as simple and efficient as those based on restricted quadtrees, the new triangulations avoid discontinuity problems among the boundaries of different patches without the need for tree balancing and extra triangles addition. Another important feature of the proposed triangulation is that it incorporates an efficient method for building triangle strips and triangle fans for t…
S-4 as a natural flavor symmetry for lepton mixing
2008
Group theoretical arguments seem to indicate the discrete symmetry S4 as the minimal flavour symmetry compatible with tribimaximal neutrino mixing. We prove in a model independent way that indeed S4 can realize exact tribimaximal mixing through different symmetry breaking patterns. We present two models in which lepton tribimaximal mixing is realized in different ways and for each one we discuss the superpotential that leads to the correct breaking of the flavor symmetry.