The use of high-resolution terrain data in gravity field prediction

Different types of gravity prediction methods for local and regional gravity evaluation are developed, tested, and compared. Four different test areas were particularly selected in view of different prediction requirements. Also different parts of the spectrum of the gravity field were considered

Toxicology of chemical mixtures: international perspective.

This paper reviews major activities outside the United States on human health issues related to chemical mixtures. In Europe an international study group on combination effects has been formed and has started by defining synergism and antagonism. Successful research programs in Europe include the development and application of statistically designed experiments combined with multivariate data analysis and modeling in vitro and in vivo studies on a wide variety of chemicals such as petroleum hydrocarbons, aldehydes, food contaminants, industrial solvents, and mycotoxins. Other major activities focus on the development of safety evaluation strategies for mixtures such as the use of toxic equivalence factors or alternatives such as the question-and-answer approach, fractionation followed by recombination of the mixture in combination with a mixture design, and quantitative structure-activity relationship analysis combined with lumping analysis and physiologically based pharmacokinetic/pharmacodynamic modeling for studying complex mixtures. A scheme for hazard identification and risk assessment of complex mixtures and a consistent way to generate total volatile organic compound values for indoor air have also been developed. Examples of other activities are carcinogenicity studies on complex mixtures (petroleum middle distillates, foundry fumes, pesticides, heterocyclic amines, diesel exhaust, solid particles), neurotoxicity studies of mixtures of solvents alone or in combination with exposure to physical factors, and toxicity studies of outdoor air pollutants, focusing on particulates. Outside the United States, toxicologists and regulators clearly have a growing interest in the toxicology and risk assessment of chemical mixtures

Statistically designed experiments to screen chemical mixtures for possible interactions.

For the accurate analysis of possible interactive effects of chemicals in a defined mixture, statistical designs are necessary to develop clear and manageable experiments. For instance, factorial designs have been successfully used to detect two-factor interactions. Particularly useful for this purpose are fractionated factorial designs, requiring only a fraction of all possible combinations of a full factorial design. Once the potential interaction has been detected with a fractionated design, a more accurate analysis can be performed for the particular binary mixtures to ensure and characterize these interactions. In this paper this approach is illustrated using an in vitro cytotoxicity assay to detect the presence of mixtures of Fusarium mycotoxins in contaminated food samples. We have investigated interactions between five mycotoxin species (Trichothecenes, Fumonisins, and Zearalenone) using the DNA synthesis inhibition assay in L929 fibroblasts. First, a central composite design was applied to identify possible interactive effects between mycotoxins in the mixtures (27 combinations from 5(5) possible combinations). Then two-factor interactions of particular interest were further analyzed by the use of a full factorial design (5 x 5 design) to characterize the nature of those interactions more precisely. Results show that combined exposure to several classes of mycotoxins generally results in effect addition with a few minor exceptions indicating synergistic interactions. In general, the nature of the interactions characterized in the full factorial design was similar to the nature of those observed in the central composite design. However, the magnitude of interaction was relatively small in the full factorial design

Estimation of toxicity of chemical mixtures through modeling of chemical interactions.

The Agency for Toxic Substances and Disease Registry (ATSDR), in collaboration with the Dutch Organization for Applied Scientific Research (TNO) Nutrition and Food Research Institute, is conducting studies to evaluate the role of chemical interactions in the expression of toxicity from low-level exposure to combinations of chemicals. The goal of this collaborative effort is to use a weight-of-evidence (WOE) approach to estimate joint toxicity of some simple chemical mixtures and to compare the estimations with test results from animal toxicity studies. The WOE approach uses individual chemical dose-response assessments and algorithms that incorporate various assumptions regarding potential chemical interactions. Qualitative evaluations were prepared for binary combinations of chemicals for the effect of butyl hydroxyanisole on di(2-ethylhexyl)phthalate, the effect of stannous chloride on Cd chloride (CdCl2), and the effect of CdCl2 on loperamide. Analyses of these evaluations and their comparison with the conclusions of laboratory animal experiments indicate that the WOE approach can be used to estimate qualitatively the joint toxicity of such simple mixtures. To further test the utility of the WOE approach, qualitative and semiquantitative evaluations were prepared for two chemical mixtures--one with similarly acting halogenated aliphatics (trichloroethylene, tetrachloroethylene, hexachloro-1,3-butadiene[HCBD], and 1,1,2-trichloro-3,3,3-trifluoropropene [TCTFP]) and the other with dissimilarly acting nephrotoxic components (mercuric chloride, lysinolalanine, D-limonene, and HCBD). These two sets of data were used to estimate the overall toxicities of the mixtures using the WOE algorithm for the mixture. The comparison of the results of the estimated toxicity with experimentally determined toxicity of the mixture of similarly acting nephrotoxicants demonstrated that the WOE approach correctly adjusted for the observed interactions in experimental animal studies. However, this was not true for the mixture of dissimilarly acting nephrotoxicants. This could be attributed to the fact that WOE evaluations are based on dose additivity that postulates that all chemicals in a given mixture act in the same way--by the same mechanism--and differ only in their potencies. In these cases the WOE approach evaluations, based on consideration of common mechanisms for simple chemical mixtures, can lead to better estimates of joint toxicity of chemical mixtures than the default assumption of dose additivity. The results also show that the WOE evaluations should be target-organ specific because none of the models tested could approximate the observed responses in organs other than the target organs in the laboratory animal studies

Juggling Sounds

Bovermann T, Groten J, deCampo A, Eckel G. Juggling Sounds. In: Proceedings of the 2nd International Workshop on Interactive Sonification. York; 2007.In this paper we describe JUGGLING SOUNDS , a system for realtime auditory monitoring of juggling patterns. We explain different approaches to gain insight into the move- ments, and possible applications in both training and jug- gling performance of single-juggler patterns. Furthermore, we report first impressions and experiences gained in a per- formance and its preparation, which took place in the CUBE at the Institute of Electronic Music (IEM), Graz

Eindrapportage Grondig Boeren met Mais Drenthe : 2012-2018

In de afgelopen decennia is de maisteelt in toenemende mate in verband gebracht met duurzaamheidsproblemen. Deze hebben te maken met verliezen van nutriënten door af- en uitspoeling, een dalend gehalte aan organische stof in de bodem, een achteruitgang van de biodiversiteit op akkers en de productie van boeikasgassen als lachgas. De opeenstapeling van negatieve aspecten heeft als gevolg dat de maisteelt een duidelijke stap moet zetten in de richting van verduurzaming. Sinds 2012 wordt er binnen Grondig Boeren met Mais gewerkt aan het verduurzamen van de maisteelt door extra aandacht voor beter bodembeheer met daarbij het streven naar gelijkblijvende opbrengsten. Dit gebeurt vanuit een systemendemonstratie, detaildemonstraties en demovelden bij satellietbedrijven. Kern in het project is de systemendemonstratie waarbij vijf verschillende manieren van telen in de jaren 2012 t/m 2018 zijn vergelijken. Hierbij is een gangbare manier van telen vergeleken met alternatieve strategieën. Eén van de alternatieve systemen is een object met aandacht voor extra organische stof. Daarnaast is er een object waarbij mineralen uit kringloop worden toegepast. In dit systeem wordt getracht de mineralen in de meest efficiënte vorm toe te passen. Een andere strategie is het twee teelten systeem waarbij eerst een snede gras geoogst wordt, gevolgd door een ultra vroeg maisras. Het vijfde alternatief dat is getoetst is het vruchtwisselingssysteem waarbij 2 jaar grasland word afgewisseld met 2 jaar snijmais. Uit de systemendemo blijkt na zeven jaar dat er alternatieve maisteeltsystemen zijn waarbij de opbrengst gelijk blijft of zelfs stijgt. De systemen organische stof, mineralen uit kringloop en vruchtwisseling hebben een positief effect op de opbrengst ten opzichte van het standaard systeem. Het organische stof en vruchtwisselingsysteem hebben daarnaast een zeer positieve organische stofbalans, ten opzichte van een ongeveer neutrale balans voor het standaard systeem. Het twee oogsten systeem presteert wisselend, de maisopbrengst blijft in de meeste jaren achter, en de grasopbrengst kan dit verschil vaak niet compenseren. Qua organische stof aanvoer is dit wel een interessant systeem. Door het telen van jaar op jaar mais op hetzelfde perceel krijgt de systemendemonstratie steeds meer te maken met ziekte. Ook onkruiden zijn een groter worden probleem, en dan met name de grasachtigen die niet meer met bodemherbiciden bestreden kunnen worden in de systemen waar het vanggewas wordt ondergezaaid. De detaildemo’s blijken een goed communicatiemiddel omdat deze duidelijk de effecten van verschillende gewasbeschermingsstrategieën laten zien op het vanggewas bijvoorbeeld. Ook wordt er gekeken naar de mogelijkheden van het mechanisch inwerken van vanggewassen. In samenwerking met de satellietbedrijven worden innovaties in de praktijk geïmplementeerd en gedeeld met collega maistelers