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The European Union (EU) has set ambitious targets to increase the overall energy efficiency and decrease the environmental impact by introducing the ‘Green Deal.’ It is an EU plan for the transition to zero greenhouse gas emissions. The overall data analyses of GHG emissions per capita and GDP value in different EU countries show that the GDP increase in 2010–2017 has not increased GHG emissions. Therefore, the link between the GDP increase through energy resource usage increase has been eliminated. However, not all of the EU 27 member states contributed to the overall EU green policy equally. The article presents the methodology for the energy and environmental performance status analyses by evaluating nine different indicators (share of renewable energy, greenhouse gases per GDP, energy intensity, primary efficiency, industry efficiency, energy consumption in households, space heating efficiency, pollutant emissions from transport and specific energy consumption of transport sector) for EU member states. Indicators have been tested through correlation analyses. The use of multidimensional Energy and climate policy indicator has been proposed to rank the performance of different EU countries. The results show that the countries with the highest score in climate and energy indicator values are Sweden, Denmark, Latvia, Austria, Finland, Ireland, and Lithuania. The lowest obtained values are Bulgaria, Poland, Hungary, the Czech Republic, and France.

District heating (DH) has been highlighted as an important part in future carbon neutral energy supply. However, the performance of different DH systems varies a lot and the existing regulations do not always motivate DH companies to move toward more sustainable heat production. Therefore, this article presents novel methodology for Climate index determination which can be further used for the comparison of DH systems. The Climate index includes seven different indicators which show DH system performance according to energy efficiency, sustainability and environmental impact dimensions. The methodology is applied for 20 different DH systems operating in Latvia. The results show that the performance of 5 natural gas-based DH systems is below the determined climate benchmark.

This paper statistically validates a novel methodology that quantifies, qualifies and spatially allocates the waste heat potential of sewage systems on an urban district level, in all cases in which real data from the sewage system does not exist or is not publicly available. The methodology is based on open data and open source technology and can be adapted to various types of cities. The results, from the application of the methodology for an example city, show that the methodology robustly calculated the paths and waste water volumetric flow from waste water sources to the waste water treatment plant. The modelled system maps the sewage system accurately within areas that have a population density close to the average. Despite small inaccuracies in the overall mapping, the methodology is able to present a good estimation of spatially distributed waste heat from water flows of the sewage system in the example city.

Recent research findings have improved the understanding of the diagnosis, pathophysiology, genetics, etiology, and treatment of peripheral, central, and functional vestibular vertigo syndromes.A literature search, with special attention to the current classification, treatment trials, Cochrane analyses, and other meta-analyses.There are internationally accepted diagnostic criteria for benign positional paroxysmal vertigo, Menière's disease, bilateral vestibulopathy, vestibular paroxysmia, and functional dizziness. Whether an acute vestibular syndrome is central or peripheral can usually be determined rapidly on the basis of the history and the clinical examination. "Cere - bellar vertigo" is a clinically important entity. For bilateral vestibulopathy, balance training is an effective treatment. For Menière's disease, preventive treatment with betahistine (48 mg and 144 mg per day) is not superior to placebo. For vestibular paroxysmia, oxcarbazepine has been shown to be effective. Treatments that are probably effective for functional dizziness include vestibular rehabilitation, cognitive behavioral therapy, and serotonin reuptake inhibitors.The diagnostic assessment of vestibular syndromes is much easier for clinicians now that it has been internationally standardized. There is still a lack of randomized, controlled trials on the treatment of, for example, Menière's disease, vestibular migraine, and "cerebellar vertigo."

This paper presents the preliminary results of the District Heating Atlas, an online tool to collect and visualize key metrics of district heating systems in Germany. Since the scarce available public information on district heating systems is widely spread and not accessible via central data, the District Heating Atlas shall be the platform to enter and call up information centrally. With its online platform it provides a user interface where relevant information can be entered and system components of the currently recorded 82 district heating systems can be compared. So far, nearly 50 % of the thermal energy fed into district heating is covered by the District Heating Atlas. The analysis shows that the data availability is more than 60 % for five of the ten key metrics recorded. On the one hand, missing correlations between the key metrics show the diversity of the district heating systems and make it difficult to formulate general valid statements that could help to calculate missing data. On the other hand, this means that district heating systems are very diverse in their structure and thus offer versatile potential for sector coupling. In addition, district heating systems must be individually optimised in order to best utilize their potential for flexibility for the entire energy system. Finally, the first comparisons with information from the biggest district heating association in Germany show a high match with the currently collected data set.

Solar energy provides a minor percentage of the thermal demand of industrial processes globally. This paper proposes a new analytical energy model for the simulation of a solar thermal steam boiler system to be integrated into an industrial environment with steam parameters at 180 °C. The purposes of this study were to evaluate the influence of solar irradiation on the share of solar steam generation and to clarify how the levelised costs of energy are influenced by different technical and economic parameters. A solar steam boiler system with parabolic trough collectors is modelled and simulations for two scenarios of 1.5 and 2.0 MW thermal output at annual irradiation of 919 kWh/(m2a) were carried out. According to the results of the feasibility study a solar share of 17 – 23 % of total annual steam generation is feasible without the integration of a thermal storage. Levelised costs of solar steam generation of 55 – 60 EUR/MWh were determined under current market conditions at mid-latitude regions. The proposed concept can benefit the wider integration of solar process heat. Beyond a solution for the production process, the integration into a connected district heating network offers further potential to reduce its primary energy factor.

A novel selenium-containing pyridazinyl-based soft scorpionate ligand (KTnse) was synthesized. It reacts with CoCl2 and NiCl2, yielding the first metallaboratrane complexes with selenium in their donor positions. Further substitution with Ag(OTf) or NaN3 allows isolation of the respective triflate or azide complexes. Reaction with Ag(OTf) leads in the case of nickel to a dinuclear, dicationic complex with a short Ni–Ni distance, while cobalt gave a mononuclear cationic species. Substitution of the chloride by azide yields with both metals the respective azide complexes. All compounds were characterized via single-crystal X-ray diffraction analysis. Density functional theory calculations on the chloride species point to oxidized cobalt(III) and nickel(III) centers.

The integration of large solar heating systems in district heating (DH) networks with large combined heat and power (CHP) plants is rarely considered. This is often due to low costs for heat but also due to subsidies for the electricity by CHP plants. Possible changes in subsidies and requirements in the reduction of fossil fuel based CO2 emissions raise an awareness of improving the operational flexibility of fossil fuelled CHP plants. This paper provides a rather simple but detailed methodology of including large solar heating systems in an existing district heating system, where heat is supplied by a large CHP plant. It uses hourly data of load and temperature patterns as well as radiation data and collector efficiency data to determine collector field size and storage size. The possibility of largely independent operation of sub-networks is analysed, which allows different system temperatures. It is demonstrated that a sub-network can operate without a back-up boiler and that both network parts benefit from the interaction. (C) 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

The ligand tris(6-tert-butyl-3-thiopyridazinyl)methane ([Tntm]H) was synthesized by the reaction of 6-tert-butyl-3-thiopyridazine with bromoform and reacted with zinc bis(trimethylsilylamide) (Zn(N{SiMe3}2)2) to form [Tntm]Zn(N{SiMe3}2) (1). This complex further reacts with protic and acidic substrates, generating the zinc thiolate complex [Tntm]Zn(StBu) (2) and zinc benzoate complex [Tntm]Zn(O2C-Me2C6H3) (3a). In all compounds [Tntm] was found to have tridentate coordination to the metal center in a κ3-C,N,N fashion, as established by single-crystal X-ray diffraction analyses. In solution, rapid dynamic κ3/κ4 equilibrium occurs at room temperature, while 1H NMR spectroscopy at −30 °C confirms the asymmetric solid-state structure. Furthermore, complex 3a shows a rearrangement reaction in solution where the ligand isomerizes to give a κ4-C,N,N,S (3b) and a κ4-C,N,S,S isomer (3c), respectively. Density functional theory (DFT) calculations reveal 3b and 3c to be 13.7 and 15.6 kJ/mol more stable in methylene ...

Meeting the heat demand of all customers attached, is the main objective for the operation of district heating (DH) systems combined with combined heat and power (CHP) plants. On the other hand, the economic ratification for the operation of CHP plants strongly depends on highly volatile electricity prices on the market. This trend will be reinforced in future, due to the additional integration and exploitation of renewable energies. Within this techno-economic field of most different operational objectives, DH systems and CHP plants must find a way for a cost-covering and efficient operation in future. Against this background, time shifts in producing and allocating heat supplied in parallel with electricity, are most attractive for DH system and CHP plant operators. Thus, margins on the electricity market could be maximized. On the other hand, heat amounts produced in parallel should be decoupled from the production of electricity as efficient as possible. Thus, thermal energy storages enter the limelight of interest for DH system operators. However, aspects concerning most different mechanisms for energetic and exergetic losses have to be considered for an optimized operation of these systems. Within this paper, the energetic and exergetic performance of sensible thermal storages will be examined. Underlying loss mechanisms of typical urban thermal storages are described qualitatively and quantified energetically and exergetically. For this purpose, existing models from literature are combined with practically relevant operational parameters for simulations.

The thiopyridazine based scorpionate ligand sodium tris(3,5-di-tert-butyl-6-thioxopyridazin-1(6H)-yl)hydroborate (NaTntBu,tBu) with two tert-butyl substituents in ortho- and para-position of the thio group was synthesized and fully characterized. Corresponding metallaboratrane complexes [M{B(PntBu,tBu)3}Cl] (M = Co, Ni, Cu) as well as [M{B(PnMe,tBu)3}Cl] (M = Co, Ni) were prepared in good yields. All complexes were characterized by spectroscopic means as well as by single crystal X-ray diffraction studies exhibiting short metal boron bonds (between 2.0186(17) A and 2.069(3) A) compared to previously reported boratranes. The two tert-butyl groups attached to the heterocycle significantly increases the solubility of NaTntBu,tBu and the derived metal complexes in apolar solvents compared to the system bearing the smaller substituents. The higher steric demand of the tert-butyl versus methyl group enhances the distortion from trigonal bipyramidal towards square pyramidal which effects the electronic situation within the complexes evidenced by the elongated metal chlorine bond trans to boron.

Zinc complexes with the mixed scorpionate ligand (6-tert-butyl-3-thiopyridazinyl)bis(2-thiomethimidazolyl)borate (PnBm) have been synthesized and characterized by NMR and IR spectroscopy. The complexes, with the general formula [(PnBm)ZnX]2 [X = Br (1a), I (1b)], are dimeric in the solid state, as determined by single-crystal X-ray diffraction analyses. The zinc atoms are tetrahedrally coordinated by the halogen atom, two sulfur atoms of PnBm, and one sulfur atom from a bridging PnBm ligand. Variable-temperature 1H NMR spectroscopy indicated dimeric structures also in solution. Upon abstraction of the bromine atom in 1a by thallium triflate, the zinc complex [(PnBm)Zn(OTf)]2 (2) was obtained and fully characterized by 1H and 13C NMR spectroscopy, elemental analysis, and single-crystal X-ray diffraction analysis.

This paper focuses on evaluating the technical, economic and ecological effects of the transition from the current high temperature charts to the lower temperature charts in the Moscow DHS by means of a developed spreadsheet-based model. A methodology suitable for assessing results of potential transition to lower temperatures in DHS of cities in Russia and worldwide is proposed and implemented in the model. The reference case of 2016 and three cases with decreased heat demand in buildings by 5, 10, and 20% were considered. The results show that fuel savings of 678–872 k t c e a can be achieved with respect to the current temperature charts in the Moscow DHS. The 110/50°С temperature chart is the most profitable option, with net present values varying from 4.64 to 10.74 bn RUB depending on the case. The 95/50°С chart, which leads to a reduction of 1.325–1.387 M t C O 2 / a , has the least impact on the environment. A more significant CO2 emissions reduction can be achieved by strong energy-saving measures and broad utilization of renewable and waste energy. The essential prerequisite for the transition is a reduction of the heat demand in buildings by at least 20%.

The German Federal Government identifies the integration of industrial waste heat and solar thermal energy into district heating systems as two measures to decarbonize the heating and cooling market in The Climate Action Plan 2050. This work determines the theoretical potential of industrial waste heat and solar thermal power within the cities’ boundaries and in relation to the cities’ district heating systems. A prognosis for the year 2030 and 2050 will be given. Poor information about industrial waste heat is bypassed by taking industrial emission from the dehst and by calculating the overall installed energy by stoichiometry. 10 %, 20 %, 30 % of the so calculated primary energy input is assumed to be meaningful integrable waste heat. The potential of solar thermal power is estimated by the solar fraction that is given with 1 %, 5 % and 15 %. The results show a high, currently unused potential of industrial waste heat sources and solar thermal power for the integration into district heating. In some cities, these energy sources can supply the heat demand of the city’s district heating system completely.

Palladium and platinum boratrane complexes of the type [M{B(PnMe,tBu)3}(PPh3)] (M = Pd 1, Pt 2b) have been prepared via the reaction of the soft scorpionate ligand potassium tris(4-methyl-6-tert-bu...

We investigate the effect of the number of arms (functionality f) on the mobility of the branch point in symmetric star polymers. For this purpose we carry out large-scale molecular dynamics simulations of simple bead–spring stars and neutron spin echo (NSE) spectroscopy experiments on center labeled polyethylene stars. This labeling scheme unique to neutron scattering allows us to directly observe the branch point motion on the molecular scale by measuring the dynamic structure factor. We investigate the cases of different functionalities f = 3, 4, and 5 for different arm lengths. The analysis of the branch point fluctuations reveals a stronger localization with increasing functionality, following 2/f scaling. The dynamic structure factors of the branch point are analyzed in terms of a modified version, incorporating dynamic tube dilution (DTD), of the Vilgis–Boué model for cross-linked networks [ J. Polym. Sci., Part B 1988, 26, 2291−2302]. In DTD the tube parameters are renormalized with the tube survival probability φ(t). As directly measured by the simulations, φ(t) is independent of f, and therefore the theory predicts no f dependence of the relaxation of the branch point. The theory provides a good description of the NSE data and simulations for intermediate times. However, the simulations, which have access to much longer time scales, reveal the breakdown of the DTD prediction since increasing the functionality actually leads to a slower relaxation of the branch point., We acknowledge financial support from the projects MAT2015-63704-P (MINECO-Spain and FEDER-UE) and IT-654-13 (Basque Government, Spain).

In the title complex, [Cu(C27H40BN6S3)(C18H15P)]·2CHCl3, the CuIatom is surrounded in a trigonal-planar arrangement by the triphenylphosphane ligand and two of the three S atoms of the scorpionate ligand with an additional 3-center–2-electron B—H...Cu interaction, with the H atom as the apex of a pyramid [B—H = 1.140 (17) Å and Cu—H = 1.826 (16) Å].

We investigate the effect of the number of arms (functionality f) on the mobility of the branch point in symmetric star polymers. For this purpose we carry out large-scale molecular dynamics simulations of simple bead-spring stars and neutron spin echo (NSE) spectroscopy experiments on center labeled polyethylene stars. This labeling scheme unique to neutron scattering allows us to directly observe the branch point motion on the molecular scale by measuring the dynamic structure factor. We investigate the cases of different functionalities f = 3, 4, and 5 for different arm lengths. The analysis of the branch point fluctuations reveals a stronger localization with increasing functionality, following 2/f scaling. The dynamic structure factors of the branch point are analyzed in terms of a modified version, incorporating dynamic tube dilution (DTD), of the Vilgis-Boué model for cross-linked networks [ J. Polym. Sci., Part B 1988, 26, 2291-2302 ]. In DTD the tube parameters are renormalized with the tube survival probability ρ(t). As directly measured by the simulations, ρ(t) is independent of f, and therefore the theory predicts no f dependence of the relaxation of the branch point. The theory provides a good description of the NSE data and simulations for intermediate times. However, the simulations, which have access to much longer time scales, reveal the breakdown of the DTD prediction since increasing the functionality actually leads to a slower relaxation of the branch point. © 2017 American Chemical Society.

In Z-type ligands the electrons for the coordination bond are formally provided by the metal. They represent an important addition to the much more extensively used L- and X-type σ-donor ligands for the development of transition metal complexes with new reactivities. We report here a new boron Z-type ligand with three tethering thiopyridazinyl donors forming exclusively complexes that feature a metal boron bond. Rational substitution pattern in the backbone of the pyridazinyl heterocycle led to a well-behaved ligand system that allowed preparation of a series of copper boratrane complexes in high yields. They are found to be more soluble in common organic solvents allowing reactivity studies in contrast to previous complexes with this type of ligand. Thus, copper complexes [Cu{B(Pn(Me,tBu))3}X] with X = Cl, OTf, N3, and κN-NCS are reported. Solution behavior was explored, and the molecular structures were determined by single-crystal X-ray diffraction analyses. The thiocyanate ligand is found to coordinate via its nitrogen atom pointing to a high oxidation state of the copper. Density functional theory calculations indicate a high positive charge on copper and a strong copper-boron interaction. Thus, here reported complexes deliver synthetic evidence for the Z-type nature of the ligand. These findings are important for further dissemination of these types of ligands in coordination chemistry.

Background: Bis(monoacylglycero)phosphate (BMP) plays a key role in the degradation and sorting of lipids in acidic organelles. Results: ABHD6 degrades BMP and co-localizes with late endosomes/lysosomes. Knockdown of ABHD6 increases hepatic BMP levels. Conclusion: ABHD6 controls BMP catabolism. Significance: ABHD6 is part of the late endosomal/lysosomal lipid-sorting machinery., α/β Hydrolase domain-containing 6 (ABHD6) can act as monoacylglycerol hydrolase and is believed to play a role in endocannabinoid signaling as well as in the pathogenesis of obesity and liver steatosis. However, the mechanistic link between gene function and disease is incompletely understood. Here we aimed to further characterize the role of ABHD6 in lipid metabolism. We show that mouse and human ABHD6 degrade bis(monoacylglycero)phosphate (BMP) with high specific activity. BMP, also known as lysobisphosphatidic acid, is enriched in late endosomes/lysosomes, where it plays a key role in the formation of intraluminal vesicles and in lipid sorting. Up to now, little has been known about the catabolism of this lipid. Our data demonstrate that ABHD6 is responsible for ∼90% of the BMP hydrolase activity detected in the liver and that knockdown of ABHD6 increases hepatic BMP levels. Tissue fractionation and live-cell imaging experiments revealed that ABHD6 co-localizes with late endosomes/lysosomes. The enzyme is active at cytosolic pH and lacks acid hydrolase activity, implying that it degrades BMP exported from acidic organelles or de novo-formed BMP. In conclusion, our data suggest that ABHD6 controls BMP catabolism and is therefore part of the late endosomal/lysosomal lipid-sorting machinery.

The paper presents some results of a recently completed research project funded by the German Science Foundation (DFG) dealing with the behavior of seismically excited granular material silos. A numerical model consisting of up to five components for describing the dynamic behavior of the silo is presented. The intergranular strain approach for hypoplasticity theory has been used for the granular material and soil–structure–interaction effects have also been taken into account. Results of numerical simulations obtained with this model are shown and compared to measurements carried out at a shaking table in Saclay, France. A squat and a slender silo have been simulated numerically in order to check the design loads specified by the European Code for silos subject to seismic loads. It follows that the Eurocode provisions for slender silos are quite good while for squat silos a reduction of the active mass assumed would be in order.

The paper presents a numerical model for the simulation of the bearing behaviour of textile-reinforced concrete structures under static load taking into account the specific bond characteristics. For the numerical simulation an assumed strain finite element based on the Reissner–Mindlin shell theory for finite rotations is used. The developed numerical model for textile-reinforced concrete allows cost efficient calculations and faster computer-aided analyses. The model verification is carried out by numerical simulations of experiments on textile-reinforced tension bars and also by simulating four-point-bending tests of textile-reinforced beams with thin-walled cross-sections under various loads. A comparison between the results of the simulations and the results of experiments is presented and discussed.

Silos generally work as storage structures between supply and demand for various goods, and their structural safety has long been of interest to the civil engineering profession. This is especially true for dynamically loaded silos, e.g., in case of seismic excitation. Particularly thin-walled cylindrical silos are highly vulnerable to seismic induced pressures, which can cause critical buckling phenomena of the silo shell. The analysis of silos can be carried out in two different ways. In the first, the seismic loading is modeled through statically equivalent loads acting on the shell. Alternatively, a time history analysis might be carried out, in which nonlinear phenomena due to the filling as well as the interaction between the shell and the granular material are taken into account. The paper presents a comparison of these approaches. The model used for the nonlinear time history analysis considers the granular material by means of the intergranular strain approach for hypoplasticity theory. The interaction effects between the granular material and the shell is represented by contact elements. Additionally, soil–structure interaction effects are taken into account.

Commissural inputs of identified second-order semicircular canal neurons were studied by separate stimulation of each of the three canal nerves on either side in the vitro frog brains. The spatial pattern of these inputs was further investigated in those second-order canal neurons that received a monosynaptic input from only one ipsilateral canal nerve (91%). Since similar results were obtained in the presence as in the absence of the cerebellum, commissural inputs must have been relayed via fibers crossing in the brainstem. Following stimulation of individual semicircular canal nerves, commissural inputs were either inhibitory or excitatory. A commissural inhibition was evoked in the majority of the recorded neurons (79%) by stimulation of the coplanar semicircular canal nerve on the contralateral side. In the remaining neurons, a commissural excitatory input was evoked. A commissural excitation, originating from the two noncoplanar semicircular canals, predominated in most (68%) of the recorded neurons and was independent of the type of second-order canal neuron. The onset latency of the canal plane-specific commissural inhibitory potentials was di- or trisynaptic. Stimulation of the contralateral VIIIth nerve evoked excitatory commissural responses. The canal plane-specific commissural inhibition therefore might have been masked by commissural excitatory responses as in earlier studies. The similar organization of the canal plane-specific commissural inhibition in frog and cat corroborates the notion of a phylogenetically conservative, basic vestibular organization. The presence of a canal plane-unspecific commissural excitation, however, appears to be a feature that is specific to frogs. The functional implications of these similarities and differences are discussed.

As a result of European energy and climate policy a growing share of renewable energy can be noted in European energy markets. Especially in the electricity market this leads to a higher volatility of the electricity price. In an open market this highly affects the share of cogeneration that is generally linked to local or district heating systems. The integration of thermal energy storage in district heating systems with cogeneration increases the flexibility of operation and thus maintains the profitability of combined heat and power units. In this paper a power-to-heat concept is proposed that offers additional benefits for thermal energy storage when electricity generation from renewable energy sources exceeds the current demand. The concept is analyzed from a technological and economic perspective.

It is notoriously difficult to study population interactions among highly mobile animals that cannot be meaningfully confined to experimental plots of limited size. For example, migratory water birds are believed to suffer from competition with resident fish populations for shared food resources. While observational evidence in support of this hypothesis is accumulating, replicated experiments addressing this issue at the proper spatial scale are lacking. Here, we report from a replicated whole-system experiment in which we stocked large (0.07 km2), shallow (< or =2.5 m deep), highly eutrophic ponds in the bird protection area "Ismaninger Speichersee mit Fischteichen" with different densities of carp and assessed the responses of water birds and their food resources during summer over several years. In all years, the biomasses of benthic macroinvertebrates, macroalgae, and macrophytes as well as the densities of herbivorous, carnivorous, and omnivorous water birds were reduced in carp ponds compared to fishless ponds. The negative effects of carp on food resources and on the numbers of water birds feeding in carp ponds increased over the season (May-September) and were stronger at high than at low stocking densities of carp. Consequently, differences in resource densities between ponds with and without carp increased, and the ranking of ponds with respect to resource densities became more predictable over the season. These factors may have contributed to a seasonal improvement of the birds' abilities to track resource densities across ponds, as suggested by tight correlations of bird numbers on ponds with resource densities late, but not early, in the season.

Zielsetzung der vorliegenden Fallstudie „Internationale Vertriebssteuerung und -controlling bei der Spezialchemie AG“ ist es, die Kompetenz der Teilnehmer in der Analyse, Bewertung und Entwicklung von Konzepten zu Vertriebssteuerung und -controlling in Business-to-Business-Markten auszubauen.

Activation maps of pre- and postsynaptic field potential components evoked by separate electrical stimulation of utricular, lagenar, and saccular nerve branches in the isolated frog hindbrain were recorded within a stereotactic outline of the vestibular nuclei. Utricular and lagenar nerve-evoked activation maps overlapped strongly in the lateral and descending vestibular nuclei, whereas lagenar amplitudes were greater in the superior vestibular nucleus. In contrast, the saccular nerve-evoked activation map coincided largely with the dorsal nucleus and the adjacent dorsal part of the lateral vestibular nucleus, corroborating a major auditory and lesser vestibular function of the frog saccule. The stereotactic position of individual second-order otolith neurons matched the distribution of the corresponding otolith nerve-evoked activation maps. Furthermore, particular types of second-order utricular and lagenar neurons were clustered with particular types of second-order canal neurons in a topology that anatomically mirrored the preferred convergence pattern of afferent otolith and canal signals in second-order vestibular neurons. Similarities in the spatial organization of functionally equivalent types of second-order otolith and canal neurons between frog and other vertebrates indicated conservation of a common topographical organization principle. However, the absence of a precise afferent sensory topography combined with the presence of spatially segregated groups of particular second-order vestibular neurons suggests that the vestibular circuitry is organized as a premotor map rather than an organotypical sensory map. Moreover, the conserved segmental location of individual vestibular neuronal phenotypes shows linkage of individual components of vestibulomotor pathways with the underlying genetically specified rhombomeric framework.

Second-order vestibular neurons (2 degrees VN) were identified in the isolated frog brain by the presence of monosynaptic excitatory postsynaptic potentials (EPSPs) after separate electrical stimulation of individual vestibular nerve branches. Combinations of one macular and the three semicircular canal nerve branches or combinations of two macular nerve branches were stimulated separately in different sets of experiments. Monosynaptic EPSPs evoked from the utricle or from the lagena converged with monosynaptic EPSPs from one of the three semicircular canal organs in ~30% of 2 degrees VN. Utricular afferent signals converged predominantly with horizontal canal afferent signals (74%), and lagenar afferent signals converged with anterior vertical (63%) or posterior vertical (37%) but not with horizontal canal afferent signals. This convergence pattern correlates with the coactivation of particular combinations of canal and otolith organs during natural head movements. A convergence of afferent saccular and canal signals was restricted to very few 2 degrees VN (3%). In contrast to the considerable number of 2 degrees VN that received an afferent input from the utricle or the lagena as well as from one of the three canal nerves (~30%), smaller numbers of 2 degrees VN (14% of each type of 2 degrees otolith or 2 degrees canal neuron) received an afferent input from only one particular otolith organ or from only one particular semicircular canal organ. Even fewer 2 degrees VN received an afferent input from more than one semicircular canal or from more than one otolith nerve (~7% each). Among 2 degrees VN with afferent inputs from more than one otolith nerve, an afferent saccular nerve input was particularly rare (4-5%). The restricted convergence of afferent saccular inputs with other afferent otolith or canal inputs as well as the termination pattern of saccular afferent fibers are compatible with a substrate vibration sensitivity of this otolith organ in frog. The ascending and/or descending projections of identified 2 degrees VN were determined by the presence of antidromic spikes. 2 degrees VN mediating afferent utricular and/or semicircular canal nerve signals had ascending and/or descending axons. 2 degrees VN mediating afferent lagenar or saccular nerve signals had descending but no ascending axons. The latter result is consistent with the absence of short-latency macular signals on extraocular motoneurons during vertical linear acceleration. Comparison of data from frog and cat demonstrated the presence of a similar organization pattern of maculo- and canal-ocular reflexes in both species.

Membrane bioreactors can replace the activated sludge process and the final clarification step in municipal wastewater treatment. The combination of bioreactor and crossflow microfiltration allows for a high chemical oxygen demand (COD) reduction of synthetic wastewater. From biomass, grown at high production rates in the aerobic bioreactor, energy rich biogas can be obtained in a subsequent anaerobic bioreactor. In this paper, experimental data from a laboratory scale membrane bioreactor are presented. The degradation of synthetic wastewater at short hydraulic retention times down to 1.5 h has been studied. The organic loading rate (OLR) has been varied in the range of 6-13 kg m(-3) per day. At steady state a high quality filtrate could be obtained at different operating conditions. At biomass concentrations of 10-22 g l(-1), COD reduction was above 95%.

The purpose of this case study is to delineate the reasoning for Siemens I&C (information and communication) to enter the ASP market. To be able to do so meaningfully, it is important to show the overall organisational configuration of Siemens detailing all available skills and competencies. Furthermore the sub-chapter provides an in-depth review of developments in the worldwide ASP market and is closed out by depicting the current Siemens ASP offering.