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This paper describes an onsite comparison of two different digital impedance bridges when performing measurements on a quantum Hall resistance standard with the purpose of realizing the SI unit of capacitance, the farad. In the EMPIR Joint Research Project 18SIB07 GIQS, graphene impedance quantum standards, the Physikalisch-Technische Bundesanstalt (PTB), Germany, developed a Josephson impedance bridge, and the Istituto Nazionale di Ricerca Metrologica (INRIM) and the Politecnico di Torino (POLITO), Italy, developed an electronic digital impedance bridge. The former is based on Josephson waveform generators and the latter on an electronic waveform synthesizer. The INRIM–POLITO impedance bridge was moved to PTB and the two bridges were compared by measuring both temperature-controlled standards and a graphene AC quantized Hall resistance (QHR) standard. The uncertainties for the calibration of 10 nF capacitance standards at 1233 Hz are within 1 × 10−8 for the PTB’s bridge and around 1 × 10−7 for the INRIM–POLITO’s bridge. The comparison mutually validates the two bridges within the combined uncertainty. The result confirms that digital impedance bridges allow the realization of the SI farad from the QHR with uncertainties comparable with the best calibration capabilities of the BIPM and the major National Metrology Institutes.

Microbiological methanation is investigated in an underground natural gas reservoir. Since H2 is involved in the process, hydrogen embrittlement of steel must inevitably be considered. Therefore, a routine for testing has been developed and a unique autoclave test bench was designed to simulate field conditions. The 2205 duplex stainless steel (UNS S31803) was investigated. Constant load tests (CLTs) and immersion tests with subsequent hydrogen analyses were performed. The specimens were exposed to different partial pressures of H2 under both dry and wet conditions (with brine). Additionally, the influence of CO2 under wet conditions was covered. Tests were performed at two different temperatures (25 °C and 80 °C) and lasted for 30 days. In general, the duplex stainless steel shows a good resistance to hydrogen embrittlement, but a significantly higher hydrogen uptake was obtained compared to other steel grades.

About 60 years after the discovery of the Josephson effect, electrical DC voltage calibrations are routinely performed worldwide—mostly using automated Josephson voltage standards (JVSs). Nevertheless, the field of electrical quantum voltage metrology is still propagating towards AC applications. In the past 10 years the fabrication of highly integrated arrays containing more than 50 000 or even 300 000 junctions has achieved a very robust level providing highly functional devices. Such reliable Josephson arrays are the basis for many novel applications mainly focussing on precision AC measurements for signal frequencies up to 500 kHz. Two versions of quantum AC standards are being employed. Programmable JVS, based on series arrays divided into subarrays, reach amplitudes up to 20 V and usually are used as quantum voltage reference in measurement systems. Pulse driven arrays reach amplitudes up to 1 V or even 4 V and are typically used as Josephson arbitrary waveform synthesizers. This paper summarizes the principal contributions from Physikalisch-Technische Bundesanstalt to the present state of JVS with particular focus on developments for precision metrological applications and our proof-of-concept demonstrations.

Zusammenfassung. Dieser Übersichtsartikel beleuchtet den aktuellen Kenntnisstand zur Ätiologie, Diagnostik und Therapie der Harninkontinenz des Mannes. In der Ätiologie der Harninkontinenz beim Mann spielt die radikale Prostatektomie eine herausragende Rolle, aber auch das benigne Prostatasyndrom, neurologische Erkrankungen oder metabolische Störungen können zu einer Harninkontinenz beim Mann führen. In der Diagnostik ist neben der Basisdiagnostik eine qualifizierte urodynamische Beurteilung unabdingbar, um die zugrunde liegenden pathophysiologischen Mechanismen aufzudecken und Chancen und Risiken der verfügbaren Therapie- bzw. Operationstechniken abschätzen zu können. Die Primärtherapie der Harninkontinenz beim Mann ist konservativ und schliesst eine qualifizierte Beckenboden- und Sphinktertherapie einschliesslich Biofeedback ein. Die Auswahl der operativen Techniken unterliegt dem Ausmass der Inkontinenz, den individuellen Gegebenheiten des Patienten, der Patientenpräferenz, der Expertise des Operateurs und einzelnen Kontraindikationen für bestimmte Verfahren. Auch ein längeres Intervall nach radikaler Prostatektomie oder ein Tumorprogress sind keine Ausschlusskriterien für eine operative Therapie. Der oft hohe Leidensdruck und das breite Spektrum von in geübten Händen wenig invasiven Operationstechniken rechtfertigen eine breite Indikationsstellung für eine prothetische Versorgung.

To avoid failures due to hydrogen embrittlement, it is important to know the amount of hydrogen absorbed by certain steel grades under service conditions. When a critical hydrogen content is reached, the material properties begin to deteriorate. The hydrogen uptake and embrittlement of three different carbon steels (API 5CT L80 Type 1, P110 and 42CrMo4) was investigated in autoclave tests with hydrogen gas (H2) at elevated pressure and in ambient pressure tests with hydrogen sulfide (H2S). H2 gas with a pressure of up to 100 bar resulted in an overall low but still detectable hydrogen absorption, which did not cause any substantial hydrogen embrittlement in specimens under a constant load of 90% of the specified minimum yield strength (SMYS). The amount of hydrogen absorbed under conditions with H2S was approximately one order of magnitude larger than under conditions with H2 gas. The high hydrogen content led to failures of the 42CrMo4 and P110 specimens.

Development of the fetal autonomic nervous system's integrative capacity in relation to gestational age and emerging behavioral pattern is reflected in fetal heart rate patterns. Conventional indices of vagal and sympathetic rhythms cannot sufficiently reflect their complex interrelationship. Universal behavioral indices of developing complex systems may provide additional information regarding the maturating complex autonomic control. We investigated fetal magnetocardiographic recordings undertaken at 10-min intervals in active ( n = 248) and quiet ( n = 111) states between 22 and 39 wk gestational age. Standard deviation of heartbeat intervals, skewness, contribution of particular rhythms to the total power, and multiscale entropy were analyzed. The multiscale entropy methodology was validated for 10-min data sets. Age dependence was analyzed by linear regression. In the quiet state, contribution of sympathovagal rhythms and their complexity over a range of corresponding short scales increased with rising age, and skewness shifted from negative to positive values. In the active state, age dependencies were weaker. Skewness as the strongest parameter shifted in the same direction. Fluctuation amplitude and the complexity of scales associated with sympathovagal rhythms increased. We conclude that in the quiet state, stable complex organized rhythms develop. In the active state, however, increasing behavioral variability due to multiple internal coordinations, such as movement-related heart rate accelerations, and external influences develop. Hence, the state-selective assessment in association with developmental indices used herein may substantially improve evaluation of maturation age and early detection and interpretation of developmental problems in prenatal diagnosis.

Objective: To describe the development of the integrative capacity of the fetal autonomic nervous system (ANS) according to gestational age and emerging behavioral states, assuming that developing integrative ANS functions are reflected in increasing autocorrelation of fetal heart rate and fetal heart rate variability markers. Methods: Magnetocardiograms of 114 healthy fetuses (21–40 weeks of gestation) were recorded. Level of fetal activity (quiet/active sleep) was estimated according to characteristic heart rate patterns. Autocorrelation functions of (i) fetal heart rate and (ii) time patterns of SDNN (standard deviation of normal-to-normal intervals) and RMSSD (root mean square of successive differences in normal-to-normal intervals) were calculated and autocorrelation was determined over different time scales. Age and activity related changes were examined using linear regression and non-parametric tests. Results: During pregnancy, autocorrelation increased in fetal heart rate signals and time patterns of SDNN and RMSSD. Short-time correlation (0–20 s) changed between 21 and 31 gestational weeks. Long-time correlation (75–300 s) accelerated later in pregnancy and did not increase in quiet heart rate patterns. Strong state-dependent changes were found with time patterns of SDNN. Conclusions: Emerging integrative ANS functions are reflected in increasing autocorrelation of fetal heart rate fluctuations over increasing time scales. The period from 21 to 31 gestational weeks seems to be critical to ANS development. Increasing long-time correlation is specific to active sleep states.

Vor genau 70 Jahren wurde PVP von Prof. Dr. Walter Reppe in der BASF erfunden und zum Patent angemeldet. Polyvinylpyrrolidon wurde zunachst als Blutplasmaersatzstoff im Zweiten Weltkrieg eingesetzt. Nach und nach fand es dann Anwendung in den unterschiedlichsten Branchen: Pharma-, Kosmetik-, Waschmittelindustrien. PVP kommt mittlerweile bei uber 100 verschiedenen technischen Anwendungen zum Einsatz, zum Beispiel in Membranen, Klebestiften, Schmelzklebern, Hydrogelen und im Pflanzenschutz. Aufgrund seiner vielseitigen Eigenschaften – wie Wasserloslichkeit, Film- und Komplexbildung, Kleb- und Bindekraft – sowie Dank seiner toxikologischen Unbedenklichkeit ist PVP eines der interessantesten technischen Spezialpolymere in der Chemie.

The increased integration of intermittent renewable energy sources such as wind and solar power is a growing challenge to the new flexible model of energy production. This integration has led to the development and promotion of energy storage systems with new long-term storage options such as power-to-gas. Power-to-gas refers to the chemical storage of electrical energy in the form of gaseous substances such as methane or hydrogen. In the chapter the term “power-to-gas” is defined as the utilization of (surplus) electrical energy from renewable power sources for the production of hydrogen in an electrolyzer and the optional synthesis of methane or other hydrocarbons from hydrogen and carbon dioxide. Power-to-gas technology makes long-term storage of electrical energy possible and makes for a more resource-efficient and flexible energy system. Other long-term energy storage technologies are currently nonexistent in national grids. Power-to-gas enables accelerated integration and continued realization of low- or zero-emission technologies such as wind power and photovoltaics, thereby promoting the achievement of both climate and energy policy objectives. Furthermore, power-to-gas allows new options in energy transport by shifting load from the power grid to the gas grid. This also reduces socioeconomic challenges such as social opposition to power grid expansions. The chapter describes the power-to-gas system, in general, and deals with multifunctional applications of the technology, in particular. Another focus is on underground storage of hydrogen (see also chapter: Energy Storage Integration ).

Die Untersuchungen haben gezeigt, das die Spontan-Verbreitung transgener Erbinformation aus Mais und Winterraps durch Pollenflug und Ernteverluste sich innerhalb der Grenzen einer naturlichen Schwankungsbreite bewegt, die vorwiegend wiegend artspezifisch begrundert ist, ihre Auspragung im Einzelfall jedoch erst in Verbindung mit den jeweiligen Wachstumsverhaltnissen erfahrt.

Mutations in the Arabidopsis COBRA gene lead to defects in cellulose synthesis but the function of COBRA is unknown. Here we present evidence that COBRA localizes to discreet particles in the plasma membrane and is sensitive to inhibitors of cellulose synthesis, suggesting that COBRA and the cellulose synthase complex reside in very close proximity on the plasma membrane. Live-cell imaging of cellulose synthesis indicated that, once initiated, cellulose synthesis appeared to proceed normally in the cobra mutant. Using isothermal calorimetry, COBRA was found to bind individual beta-1,4-linked glucan chains with a KA of 3.2muM. Competition assays suggests that COBRA binds individual beta-1,4-linked glucan chains with higher affinity than crystalline cellulose. Solid-state nuclear magnetic resonance (SSNMR) studies of the cell wall of the cobra mutant also indicated that, in addition to decreases in cellulose amount, the properties of the cellulose fibrils and other cell wall polymers differed from wild type by being less crystalline and having an increased number of reducing ends. We interpret the available evidence as suggesting that COBRA facilitates cellulose crystallization from the emerging beta-1,4 glucan chains by acting as a ''polysaccharide chaperone''.

Ribosomal ribonucleic acids are excellent marker molecules for the elucidation of bacterial phylogeny; they also provide useful target sites for identification and detection with nucleic acid probes. Based on the currently available 16S rRNA sequence data, bacteria of the rhizobial phenotype (plant nodulation, nitrogen fixation) are members of three moderately related phylogenetic sub-groups of the α-subclass of the Proteobacteria: i.e. the rhizobia group, the bradyrhizobia group, and the azorhizobia group. All rhizobia, azo-, brady-, meso-and sinorhizobia are closely related to and in some cases phylogenetically intermixed with, non-symbiotic and/or non-nitrogen-fixing bacteria. Especially in the case of Bradyrhizobium japonicum strains, the 16S rRNA sequence data indicate substantial heterogeneity. Specific probe design and evaluation are discussed. A multiprobe concept for resolving specificity problems with group specific probes is presented. In situ identification with group specific probes of rhizobia in cultures as well as rhizobia and cyanobacteria within plant material is shown.

16S rRNA gene libraries were prepared by polymerase chain reaction amplification and cloning from soil samples taken periodically from a field with genetically modified plants. Sequence analyses of the cloned rDNAs indicated that 140 of them clustered apart from known bacterial phyla. Based on 31 full sequences a new phylum could be defined. It includes Holophaga foetida, 'Geothrix fermentans' and Acidobacterium capsulatum as the only cultured species so far. Therefore, this line of descent was named the Holophagal Acidobacterium phylum. About 50 published partial sequences of cloned rDNAs retrieved from soil, freshwater sediments or activated sludge from different continents indicate the occurrence of further representatives of this phylum. Two specific hybridization probes were constructed for members of one of four subclusters. A careful data analysis revealed the importance and problems of identifying and dealing with artefacts such as chimeric structure when defining new phylogenetic groups based mainly upon cloned amplified rDNAs. For the first time, the presence of bacterial cells representing this group could be shown in soil, sediment, activated sludge and lake snow by in situ hybridization.

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Der schweizerische Bundesrat hat auf den 15. September 1913 eine internationale Arbeiterschutzkonferenz mit der folgenden Begrundung einberufen: „Die Bestrebungen, Fragen des Arbeiterschutzes auf dem Wege internationaler Vereinbarungen zu regeln, haben durch den Abschlus der zwei Staatsvertrage vom 26. September 1906 uber das Verbot der industriellen Nachtarbeit der Frauen und uber das Verbot der Verwendung von weisem Phosphor in der Zundholzindustrie einen ersten und daher um so hoher anzuschlagenden Erfolg erzielt.

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