Die Einwirkung von bei der Papierfabrikation verwendeten Farbstoffen auf die Tierwelt des Wassers

Ohne ZusammenfassungMitteilung aus der Hydrobiologischen Abteilung der Landwirtschaftlichen Versuchsstation Münster i. W.     

Determination of organic silicon compounds in biogas from wastewater treatments plants,landfills, and co-digestion plants

The study determined the organic silicon compounds in biogases from landfills, wastewater treatment plants (WWTPs), and biogas plants processing different organic material. The aim was to provide information for gas utilisation applications, as siloxanes are reported to shorten the life time of engines when biogas is used for energy production. In total, 48 samples were measured. The total concentration of organic silicon compounds in landfill and WWTP gases varied from 77 to 2460 μg/m³ while the concentrations in biogases from biogas plants varied from 24 to 820 μg/m³. The total concentration of organic silicon compounds was lowest (24 μg/m³) in the biogas plant processing grass and maize, and highest (2460 μg/m³) in one of the studied WWTP. The most common compounds in WWTPs and in biogas plants processing also sewage sludge were D4 and D5 while in landfills the most common compounds were D4 and L2 followed by trimethyl silanol. The effect of condensation of biogas on concentrations of organic silicon compounds was studied in one of the landfills and a negligible effect on concentrations was detected.     

Multicore compilation strategies and challenges

To overcome challenges stemming from high power densities and thermal hot spots in microprocessors, multicore computing platforms have emerged as the ubiquitous computing platform from servers down through embedded systems. Unfortunately, providing multiple cores does not directly translate into increased performance or better energy efficiency for most applications. The burden is placed on software developers and tools to find and exploit coarse-grain parallelism to effectively make use of the abundance of computing resources provided by these systems. Concurrent applications are much more complex to develop than their single-threaded ancestors, thus software development tools will be critical to help programmers create both high performance and correct software. This article provides an overview of parallelism and compiler technology to help the community understand the software development challenges and opportunities for multicore signal processors.     

Feasibility of a neutron detector-dosemeter based on single-event upsets in dynamic random-access memories

In an attempt to investigate the effect of radiation quality, dose and specific repair pathways on correct and erroneous rejoining of DNA double strand breaks (DSBs), an assay was applied that allows the identification and quantification of incorrectly rejoined DSB ends produced by ionising radiation. While substantial misrejoining occurs in mammalian cells after high acute irradiation doses, decreasing misrejoining frequencies were observed in dose fractionation experiments with X rays. In line with this finding, continuous irradiation with gamma rays at low dose rate leads to no detectable misrejoining. This indicates that the probability for a DSB to be misrejoined decreases drastically when DSBs are separated in time and space. The same dose fractionation approach was applied to determine DSB misrejoining after alpha particle exposure. In contrast to the results with X rays, there was no significant decrease in DSB misrejoining with increasing fractionation. This suggests that DSB misrejoining after alpha irradiation is not significantly affected by a separation of particle tracks. To identify the enzymatic pathways that are involved in DSB misrejoining, cell lines deficient in non-homologous end-joining (NHEJ) were examined. After high X ray doses, DSB misrejoining is considerably reduced in NHEJ mutants. Low dose rate experiments show elevated DSB misrejoining in NHEJ mutants compared with wild-type cells. The authors propose that NHEJ serves as an efficient pathway for rejoining correct break ends in situations of separated breaks but generates genomic rearrangements if DSBs are close in time and space.     

Native Spanish-Speaking Children Reading in English: Toward a Model of Comprehension.

A structural equation model of second language (L2; English) reading comprehension was tested on a sample of 135 Spanish-speaking 4th-grade English-language learners (ELLs). The model included 2 levels: decoding and oral language. English decoding measures included alphabetic knowledge and fluency. English oral language measures included vocabulary knowledge and listening comprehension. The model had reasonable goodness of fit. Decoding skills played a less predictive role than oral language proficiency. L2 listening comprehension made an independent, proximal contribution to L2 reading comprehension, whereas L2 vocabulary knowledge assumed both proximal and distal relationships with L2 reading comprehension. Results suggest that, given adequate L2 decoding ability, L2 vocabulary knowledge is crucial for improved English reading comprehension outcomes for Spanish-speaking ELLs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)