Resonance characteristics of a cavity-operated electrodelesshigh-pressure microwave discharge system

To characterize the resonance behavior of cavity-operated electrodeless high-pressure microwave discharge systems, a microwave circuit is developed that allows high-power network analysis during the operation of the discharge. The frequency-dependent complex impedance of the cavity including the plasma is obtained from a reflection measurement in the range 1.5 GHz-4.5 GHz. This method allows an observation of the actual resonance frequency and the actual vectorial mismatch so that a coupling efficiency >99% can always be achieved with proper adjustment of the operation frequency and coupling probe. Experimental results with a cylindrical TM₀₁₀ cavity and a coaxially situated discharge show a decrease of the resonance frequency with increasing power (increasing plasma temperature, electron density, and electrical conductivity) depending on the discharge geometry and the plasma composition. In accordance with a simple one-dimensional model, the Q factor passes through a minimum at medium power levels, where the cavity discharge system absorbs the microwave energy most effectively     

Embryonic cardiomyocyte hypoplasia and craniofacial defects in G alpha q/G alpha 11-mutant mice

Heterotrimeric G proteins of the Gq class have been implicated in signaling pathways regulating cardiac growth under physiological and pathological conditions. Knockout mice carrying inactivating mutations in both of the widely expressed G alpha q class genes, G alpha q and G alpha 11, demonstrate that at least two active alleles of these genes are required for extrauterine life. Mice carrying only one intact allele [G alpha q(-/+);G alpha 11(-/-) or G alpha q(-/-);G alpha 11(-/+)] died shortly after birth. These mutants showed a high incidence of cardiac malformation. In addition, G alpha q(-/-);G alpha 11(-/+) newborns suffered from craniofacial defects. Mice lacking both G alpha q and G alpha 11 [G alpha q(-/-);G alpha 11(-/-)] died at embryonic day 11 due to cardiomyocyte hypoplasia. These data demonstrate overlap in G alpha q and G alpha 11 gene functions and indicate that the Gq class of G proteins plays a crucial role in cardiac growth and development.     

G alpha 15 and G alpha 16 couple a wide variety of receptors to phospholipase C

The murine G-protein alpha-subunit G alpha 15 and its human counterpart G alpha 16 are expressed in a subset of hematopoietic cells, and they have been shown to regulate beta-isoforms of inositide-specific phospholipase C. We studied the ability of a variety of receptors to interact with G alpha 15 and G alpha 16 by cotransfecting receptors and G-protein alpha-subunits in COS-7 cells. Activation of beta 2 adrenergic and muscarinic M2 receptors in cells expressing the receptors alone or together with G alpha q, G alpha 11, or G alpha 14 led to a very small stimulation of endogenous phospholipase C. However, when the receptors were coexpressed with G alpha 15 and G alpha 16, addition of appropriate ligands caused a severalfold increase in inositol phosphate production which was time- and dose-dependent. A similar activation of phospholipase C was observed when several other receptors which were previously shown to couple to members of the Gi and Gs family were coexpressed with G alpha 15/16. In addition, stimulation of inositol phosphate formation via receptors naturally coupled to phospholipase C was enhanced by cotransfection of G alpha 15 and G alpha 16. These data demonstrate that G alpha 15 and G alpha 16 are unique in that they can be activated by a wide variety of G-protein-coupled receptors. The ability of G alpha 15 and G alpha 16 to bypass the selectivity of receptor G-protein interaction can be a useful tool to understand the mechanism of receptor-induced G-protein activation. In addition, the promiscuous behavior of G alpha 15 and G alpha 16 toward receptors may be helpful in finding ligands corresponding to orphan receptors whose signaling properties are unknown.     

A flexible air separation process: 1. Design and steady-state optimizations

The flexible operation of energy-intensive processes, such as cryogenic air separation, has economic potential due to increasing fluctuations of the electricity markets. Multiproduct air separation processes with high ratios of liquid product are very promising for flexible operation due to storable products. We present a process design with an integrated liquefication cycle and liquid assist operation, that facilitates a high liquid product ratio and a flexible process operation. We use a mechanistic dynamic process model in steady-state process optimizations covering the wide operational range of the proposed process. The optimization results show that the power demand can be varied in a range from 3.5 to 28 MW without violating operational constraints by changing the nitrogen and oxygen production rates. Thus, the proposed process is a promising air separation candidate for flexible operation with respect to fluctuating electricity markets.     

Impaired motor coordination and persistent multiple climbing fiber innervation of cerebellar Purkinje cells in mice lacking Galphaq

Mice lacking the alpha-subunit of the heterotrimeric guanine nucleotide binding protein Gq (Galphaq) are viable but suffer from ataxia with typical signs of motor discoordination. The anatomy of the cerebellum is not overtly disturbed, and excitatory synaptic transmission from parallel fibers to cerebellar Purkinje cells (PCs) and from climbing fibers (CFs) to PCs is functional. However, about 40% of adult Galphaq mutant PCs remain multiply innervated by CFs because of a defect in regression of supernumerary CFs in the third postnatal week. Evidence is provided suggesting that Galphaq is part of a signaling pathway that is involved in the elimination of multiple CF innervation during this period.     

Phospholipase cbeta4 is specifically involved in climbing fiber synapse elimination in the developing cerebellum

Elimination of excess climbing fiber (CF)-Purkinje cell synapses during cerebellar development involves a signaling pathway that includes type 1 metabotropic glutamate receptor, Galphaq, and the gamma isoform of protein kinase C. To identify phospholipase C (PLC) isoforms involved in this process, we generated mice deficient in PLCbeta4, one of two major isoforms expressed in Purkinje cells. PLCbeta4 mutant mice are viable but exhibit locomotor ataxia. Their cerebellar histology, parallel fiber synapse formation, and basic electrophysiology appear normal. However, developmental elimination of multiple CF innervation clearly is impaired in the rostral portion of the cerebellar vermis, in which PLCbeta4 mRNA is predominantly expressed. By contrast, CF synapse elimination is normal in the caudal cerebellum, in which low levels of PLCbeta4 mRNA but reciprocally high levels of PLCbeta3 mRNA are found. These results indicate that PLCbeta4 transduces signals that are required for CF synapse elimination in the rostral cerebellum.     

Methanol findet zu wenig Beachtung als Kraftstoff und Chemierohstoff der Zukunft

Energy sources in the future are a vividly discussed topic and many statements have been published recently by scientific societies and organizations. However, in most cases an overall view on the topic energy, fuels, raw materials and climate is missing and only little attention is given to the recycling of CO₂ – the use as a raw material, e.g., for the synthesis of methanol whereas emphasis is on carbon capture and storage.     

Hot rolling of AISI 304 tailored strips produced by twin roll strip casting

A process for the production of steel strips with an optimized cross section by means of twin-roll strip casting has recently been developed at the Institute of Metal Forming and offers considerable technical and commercial potentials. This production concept is based on the use of profiled casting rolls which continuously transfer the profile geometry to the solidified strip. In order to reduce the internal porosity and improve the surface finish the cast strip was hot rolled using profiled rolls. Offline and inline rolling experiments were performed to prove the effectiveness of this combined forming process. This paper describes the design of a proper rolling tool and the effect of this forming step on the final profile geometry, surface quality, internal porosity and mechanical properties of the strip. The experiments showed that a rolling step with 15 % thickness reduction already allows the global internal porosity to be reduced by 48 % and the strip surface roughness to reach a minimum value of R_a = 2.3 µm. The tensile strength is improved after the hot rolling operation and the obtained values are within the 500–700 MPa range specified by the norm EN 10088-3 for the stainless steel AISI 304. The prescribed ultimate elongation of 45 % is also reached.     

Wind und Kohle: Die technische Photosynthese

The increasing energy demand, the associated CO₂ emissions, and the concurrently decreasing reserves of fossil fuels require new concepts for sustainable energy production. The so‐called Adam‐and‐Eve principle for CO₂‐free production of methanol from coal and nuclear energy is revisited and adapted to today's circumstances. Electrolysis of water using renewable electricity is applied for H₂ production. Simultaneously, coal and the oxygen formed during electrolysis are burned in an oxyfuel process, generating electricity and relatively pure CO₂. Hydrogen from electrolysis and CO₂ are converted to methanol, which can then be used as chemical‐ and energy feedstock.     

The FKBP51 Inhibitor SAFit2 Restores the Pain-Relieving C16 Dihydroceramide after Nerve Injury

Neuropathic pain is a pathological pain state with a broad symptom scope that affects patients after nerve injuries, but it can also arise after infections or exposure to toxic substances. Current treatment possibilities are still limited because of the low efficacy and severe adverse effects of available therapeutics, highlighting an emerging need for novel analgesics and for a detailed understanding of the pathophysiological alterations in the onset and maintenance of neuropathic pain. Here, we show that the novel and highly specific FKBP51 inhibitor SAFit2 restores lipid signaling and metabolism in nervous tissue after nerve injury. More specifically, we identify that SAFit2 restores the levels of the C16 dihydroceramide, which significantly reduces the sensitization of the pain-mediating TRPV1 channel and subsequently the secretion of the pro-inflammatory neuropeptide CGRP in primary sensory neurons. Furthermore, we show that the C16 dihydroceramide is capable of reducing acute thermal hypersensitivity in a capsaicin mouse model. In conclusion, we report for the first time the C16 dihydroceramide as a novel and crucial lipid mediator in the context of neuropathic pain as it has analgesic properties, contributing to the pain-relieving properties of SAFit2.