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Since the liberalisation of the European electricity sector, forward and futures contracts have gained significant interest of market participants due to risk management reasons. For pricing of these contracts an important fact concerns the non-storability of electricity. In this case, according to economic theory, forward prices are related to the expected spot prices which are built on fundamental market expectations. In the following article the crucial impact parameters of forward electricity prices and the relationship between forward and future spot prices will be assessed by an empirical analysis of electricity prices at the European Energy Exchange and the Nord Pool Power Exchange. In fact, price formation in the considered markets is influenced by historic spot market prices yielding a biased forecasting power of long-term contracts. Although market and risk assessment measures of market participants and supply and demand shocks can partly explain the futures-spot bias inefficiencies in the analysed forward markets cannot be ruled out.

The objective of this study was to describe the cephalometric characteristics of the open bite, and to classify the open bite according to individualized norms. The lateral cephalograms of 134 patients with an anterior open bite (min —0.5 mm) were analyzed. Patients were classified according to the inclination of the jaws, applying the principles of individualized cephalometry. The harmony box described by Hasund [11] was used to define individualized norms for the inclination of the upper and lower jaws in each patient. The open bite was classified into four sub-types: (1) dental, (2) skeletal with enlarged ML-NSL angle, (3) skeletal with reduced ML-NSL angle, and (4) skeletal with deviations in upper and lower jaws. A skeletal open bite was found in 89 patients (66.4%). A dental open bite was found in 45 patients (33.6%). A number of significant differences were found between these four groups using single-factor variance analysis and the Bonferroni a posteriori test, (p ≤ 0.05, p ≤ 0.01, p ≤ 0.001). The most prominent variables were index value of anterior facial hight, total facial height ratio, gonial angle, and Y-axis. No significant differences were found for overbite, however. It was possible to use individualized norms to classify the open bite into four sub-types. The demarcation between the four groups was supported statistically. The extent of the anterior open bite does not allow any conclusions as to the craniofacial pattern.

We consider the environmental Leontief model, which is an input–output model augmented by pollution-generation and pollution-abatement sectors. Two formulations of this model, dating back to Leontief's work in 1970, can be found in the literature. One formulation treats an exogenously given vector of the tolerated level of pollutants (environmental standards) as a negative variable on the right-hand side of the model. The other formulation supposes that each industry eliminates a given proportion of the pollution that it creates, so that the proportions of gross pollutants which are subject to treatment by each sector enter as given parameters. Even in the case when the levels of production and abatement in the two different model formulations are equal, the solutions of the dual or price model are different for cases where some net pollution is left untreated. First, the analytical relationship between the two price models is established. Secondly, both models formulated in a linear programming framework...

The aim of the present study was to investigate the soft-tissue morphology and profile line of prognathic patients in the Saxony-Anhalt region of central Germany. To this effect, the profile photographs and lateral cephalograms taken at treatment start for 34 adults (17 female patients, mean age: 22.6 years; 17 male patients; mean age: 23.2 years), Class III subjects who had not undergone orthodontic treatment, were measured and, by means of statistical analysis, the findings were compared with those of an age-matched control group (17 female subjects, mean age: 21.4 years; 17 male subjects, mean age: 23.8 years). Patients with Class III anomalies had a significantly longer and thinner lower lip and a smaller lower subnasal angle than the control subjects. The lower face was markedly enlarged. Furthermore, the osseous profile line was significantly flatter and the soft-tissue convexity was considerably reduced compared with the control group. Hence the prognathic patients of central Germany manifested typical features of the prognathic profile line. To elucidate typical regional features, further comparative studies are required.

An einen Diabetes denkt man bei einer Reihe von zum Teil unspezifischen Symptomen. Die Symptome sind annahernd in fallender Haufigkeit angeordnet: Durst, Polydipsie; haufiges Wasserlassen, Polyurie, Exsikkose; Wachstumsstorung, Bettnassen und Schulprobleme bei Kindern mit Typ 1-Diabetes; korperliche und mentale Leistungsminderung mit Abgeschlagenheit, Druckgefuhl im Kopf; psychische Probleme; Gewichtsverlust beim Typ 1- und auch Typ 2-Diabetes; Sehverschlechterungen bei osmotisch aufquellendem Linsenapparat; Juckreiz (u. a. Pruritus vulvae); orthostatische Beschwerden (Dehydratation) Appetitlosigkeit, Inappetenz, aber auch Polyphagie; Potenzstorungen, Libidoverlust; Muskelkrampfe; Gefuhlsstorungen, Neuropathie; Ubelkeit und Bauchschmerzen bis zum akuten Abdomen (Pseudoperitonitis); Verlangsamung bis zur Eintrubung; Infektanfalligkeit: rezidivierende Harnwegsinfekte, Hautmykosen, Furunkulosen, Pyodermie; Amenorrhoe, Regelstorungen, verminderte Fruchtbarkeit bei Frauen.

The two-staged WWTP ‘Gut Grosslappen’ has a capacity of 2 mio. PE. It comprises a pre-denitrification in the first stage using recirculation from the nitrifying second stage. A residual post-denitrification in a downstream sand filter is required in order to achieve the effluent standards. Presently the process water from sludge digestion is treated separately by nitrification/denitrification. Due to necessary reconstruction of the biological stages, the process water treatment was included in the future overall process concept of the WWTP. A case study was conducted comparing the processes nitritation/denitrititation and deammonification with nitrification/denitrification including their effect on the operational costs of the planned main flow treatment. Besides the different operating costs the investment costs required for the process water treatment played a significant role. Six cases for the process water treatment were compared. As a result, in Munich deammonification can only be recommended for long-term future developments, due to the high investment costs, compared with the nitritation/denitritation alternative realizable in existing tanks. The savings concerning aeration, sludge disposal and chemicals were not sufficient to compensate for the additional investment costs. Due to the specific circumstances in Munich, for the time being the use of existing tanks for nitritation/denitritation proved to be most economical.

It is often claimed that there is a trade-off between economic goals and the quality of the environment. For this reason, an environmental input-output optimization model with multiple objectives is formulated. The criteria are the minimization of factor costs to produce the Gross National Product and the minimization of net pollution for a given level of final demand. Using the LeChatelier-Samuelson principle, we analyze the changes in the production of the sectors and in the prices of the goods (described by the dual model) due to the change in the preferences of the decision makers. It can be shown that higher weights for the environmental objectives imply — in tendency —non-decreasing production of the sectors andnon-decreasing abatement activities. The changes of prices are ambiguous. The condition for increasing prices is given. To some degree, the opposite results can be achieved, if maximization of the value of final demand (or of private consumption) and minimization of net pollution under the constraints for primary input are taken as objective functions. In this case, increasing weights for environmental goals will leadin tendency tonon-increasing final demand and tonon-increasing net pollution. Under given conditions, higher environmental quality will be achieved bynon-increasing gross production and abatement activities.

We consider the Leontief model augmented with pollution-generation and pollution-abatement sectors. The conditions to ensure the existence of non-negative solutions for the total output and for the vector of abatement activities, depending on the exogenously given final demand and environmental standards, are presented. They are extensions and modifications of the conditions for a single pollutant derived, for example, by Miller and Blair.