Towards a Precise Semantics for Object-Oriented Modeling Techniques

In this paper we present a possible way how a precise semantics of object oriented modeling techniques can be achieved and what the possible benefits are .We outline the main modeling techniques used in the SysLab project sketch how a precise semantics can be given and how this semantics can be used during the development process.Comment: 6 pages, 0 figure

Climate Change: The Ultimate Cereal Killer: The Impact of Temperature and Precipitation on Agricultural Yields

The global food supply depends on agricultural production, but as the negative effects of climate change are exacerbated by human activity, how will agriculture need to change to accommodate both climate change and the increasing population? In order to understand what adaptations will be necessary, we perform analysis on the relationship between climate change (temperature and precipitation) and crop yields (barley, rice, and soybean). We take a multinational approach, using ten countries for each model, to see the global impact of climate change on production. Testing many models, we settle on country-specific time trends, eliminating many confounding variables by focusing on climate’s effect on variations from the trend. For all three crops, the analysis shows that temperature has a significant effect on output while precipitation has a negligible effect. The models account for upwards of 96% of the variation from the trend for each crop on a year-by-year basis. In a similar way to how irrigation has altered agriculture\u27s reliance on natural water supplies, we now need to focus on developing technology to counteract the effects of increasing temperatures on crop growth

Biologische producten en gezondheid. Resultaten melkonderzoek 2005

In het verleden is al aangetoond dat de biologische productiemethode maatschappelijke voordelen heeft op terreinen als milieu, biodiversiteit, bodemkwaliteit, dierenwelzijn en pesticidenresidu. Indirect dragen deze kwaliteiten bij aan de gezondheid van de mens. Nu beginnen ook steeds meer onderzoeksresultaten beschikbaar te komen waaruit blijkt dat de biologische productiemethode ook leidt tot voedsel dat meer gezonde stoffen bevat. Biologische producten blijken gemiddeld gelijk of hoger te scoren op gezonde stoffen o.a. vitamine C gehaltes, mineralen, anti-oxidanten en eiwitkwaliteit dan reguliere producten. En biologische producten blijken gelijk of lager te scoren op ongezonde stoffen zoals nitraat, residuen van bestrijdingsmiddelen en contaminanten. Als verkennend onderzoek naar verschillen in koemelk werd in februari 2005 koemelk van 5 biologische en 5 gangbare buurbedrijven onderzocht. Een duidelijk verschil in bedrijfsvoering is dat biologische koeien minder krachtvoer en meer klaver en gras eten. De hoeveelheid CLA's en omega-3-vetzuren was in de onderzochte biologische melk significant hoger. In smaak was er geen eenduidig verschil in beoordeling. Ook de gezondheidstoestand van de koeien werd gemeten via immunologisch onderzoek. Hieruit bleek dat biologische koeien beter kunnen reageren op infecties, ze zijn dus robuuster. Deze gezondheidsmeting van de koe past in de hypothese dat de cyclus van een gezonde bodem, gezonde gewassen, gezonde dieren ook leidt tot gezonde producten voor de mens. Bij de vernieuwende meetmethoden voor 'geordendheid' van de structuur (biofotonen en voedingskristallisaties) scoort de biologische melk systematisch hoger op 'geordendheid', 'integratie’ en ‘coördinatie'. Uit onderzoek naar voederrantsoenen en naar moedermelk blijkt dat hogere CLA-gehaltes in de keten doorgeven worden via het voer (veel gras en klaver), naar de koemelk tot in de menselijke moedermelk

Sleep Spindles Are Related to Schizotypal Personality Traits and Thalamic Glutamine/Glutamate in Healthy Subjects

Background: Schizophrenia is a severe mental disorder affecting approximately 1% of the worldwide population. Yet, schizophrenia-like experiences (schizotypy) are very common in the healthy population, indicating a continuum between normal mental functioning and the psychosis found in schizophrenic patients. A continuum between schizotypy and schizophrenia would be supported if they share the same neurobiological origin. Two such neurobiological markers of schizophrenia are: (1) a reduction of sleep spindles (12-15 Hz oscillations during nonrapid eye movement sleep), likely reflecting deficits in thalamo-cortical circuits and (2) increased glutamine and glutamate (Glx) levels in the thalamus. Thus, this study aimed to investigate whether sleep spindles and Glx levels are related to schizotypal personality traits in healthy subjects. Methods: Twenty young male subjects underwent 2 all-night sleep electroencephalography recordings (128 electrodes). Sleep spindles were detected automatically. After those 2 nights, thalamic Glx levels were measured by magnetic resonance spectroscopy. Subjects completed a magical ideation scale to assess schizotypy. Results: Sleep spindle density was negatively correlated with magical ideation (r = −.64, P .1). Conclusions: The common relationship of sleep spindle density with schizotypy and thalamic Glx levels indicates a neurobiological overlap between nonclinical schizotypy and schizophrenia. Thus, sleep spindle density and magical ideation may reflect the anatomy and efficiency of the thalamo-cortical system that shows pronounced impairment in patients with schizophreni

Gravitational waves from self-ordering scalar fields

Gravitational waves were copiously produced in the early Universe whenever the processes taking place were sufficiently violent. The spectra of several of these gravitational wave backgrounds on subhorizon scales have been extensively studied in the literature. In this paper we analyze the shape and amplitude of the gravitational wave spectrum on scales which are superhorizon at the time of production. Such gravitational waves are expected from the self ordering of randomly oriented scalar fields which can be present during a thermal phase transition or during preheating after hybrid inflation. We find that, if the gravitational wave source acts only during a small fraction of the Hubble time, the gravitational wave spectrum at frequencies lower than the expansion rate at the time of production behaves as $\Omega_{\rm GW}(f) \propto f^3$ with an amplitude much too small to be observable by gravitational wave observatories like LIGO, LISA or BBO. On the other hand, if the source is active for a much longer time, until a given mode which is initially superhorizon ($k\eta_* \ll 1$), enters the horizon, for $k\eta \gtrsim 1$, we find that the gravitational wave energy density is frequency independent, i.e. scale invariant. Moreover, its amplitude for a GUT scale scenario turns out to be within the range and sensitivity of BBO and marginally detectable by LIGO and LISA. This new gravitational wave background can compete with the one generated during inflation, and distinguishing both may require extra information.Comment: 21 pages, 2 figures, added discussion about numerical integration and a new figure to illustrate the scale-invariance of the GW power spectrum, conclusions unchange