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A satellite laboratory "toolkit" consisting of a handheld Raman spectrometer, portable direct analysis in real-time mass spectrometer (DART-MS) and portable Fourier transform infrared (FT-IR) spectrometer was employed to examine 926 pharmaceutical, unknown and dietary supplement products collected at an international mail facility (IMF) for the presence of declared and undeclared active pharmaceutical ingredients (APIs) over the course of 68 working days. The toolkit successfully identified over 650 APIs, including over 200 unique APIs, using two or more devices. The performance of each individual device, and toolkit as a whole, were evaluated on all products and a subset of the products was forwarded to full-service laboratories for confirmatory analysis to determine false positive and false negative rates of the toolkit. The subset consisted of seven negative items (those not found to contain APIs using the toolkit) and 124 positive items (those found to contain at least one API using the toolkit). Overall, no false positives were detected in the negative items and only four false negatives and five false positives were detected in the positive items. Regarding the positive items, 119 of the 124 items were found to contain at least one API using at least two toolkit devices; each of these APIs were confirmed by a full-service laboratory. Furthermore, 90.2% of the APIs found by confirmatory laboratory analysis were detected by at least two toolkit devices. Based on these metrics and the fact that no false positives were detected by more than one device, it was concluded that when the toolkit detects and subsequently verifies/confirms an API using two or more devices, the results are as reliable as those generated by a full-service laboratory.

Trading electricity across market zones furthers competitive power prices, security of supply and the integration of renewable energy. In the European Union, flow-based market coupling is the target model to compute correct trading capacities between markets, while approximating physical grid constraints. The methodology relies on predictive, carefully designed parameters to maximize trading opportunities, while keeping congestion management at acceptable levels. This paper explains the fundamentals of flow-based market coupling. It provides an open-access model based on a test network and its data. By providing a guide to the theory and conducting several case studies, the functioning and effects of the most influential parameters are demonstrated. Innovative aspects of this paper are its illustrative nature and its answer to the following research questions: (1) What is the effect of (a) generation shift keys and (b) threshold choice on the selection of critical network elements? (2) What is the effect of (a) generation shift keys, (b) selected critical network elements and (c) security margins on market coupling and congestion management results? It also addresses the effect of higher shares of renewable energy and minimum trading capacities on flow-based market coupling. This analysis shows that (1) the effects of flow reliability margins and selected critical network elements dominate the effect of generation shift keys on flow-based market coupling domains, (2) power systems with an increasing share of renewable energy may necessitate re-adjusted parameters and (3) minimum trading capacities can be guaranteed by redispatch or altering the base case.

Distortion-product otoacoustic emissions (DPOAEs) arise in the cochlea in response to two tones with frequencies f1 and f2 and mainly consist of two components, a nonlinear-distortion and a coherent-reflection component. Wave interference between these components limits the accuracy of DPOAEs when evaluating the function of the cochlea with conventional continuous stimulus tones. Here, DPOAE components are separated in the time domain from DPOAE signals elicited with short stimulus pulses. The extracted nonlinear-distortion components are used to derive estimated distortion-product thresholds (EDPTs) from semi-logarithmic input-output (I/O) functions for 20 normal-hearing and 21 hearing-impaired subjects. I/O functions were measured with frequency-specific stimulus levels at eight frequencies f2 = 1,…, 8 kHz (f2/f1 = 1.2). For comparison, DPOAEs were also elicited with continuous primary tones. Both acquisition paradigms yielded EDPTs, which significantly correlated with behavioral thresholds (p

Mitarbeitende von Bildungseinrichtungen gestalten das Programm und die darin gebündelten Bildungsangebote unter Nutzung verschiedener Planungsstrategien wie der Neuentwicklung und Fortschreibung. Im vorliegenden Beitrag werden Planungsstrategien eines privaten Bildungsdienstleisters empirisch herausgearbeitet und in eine abschließende Systematisierung aus bekannten und neu identifizierten Planungsstrategien überführt: Neuentwicklung von Angeboten und Methoden, Umsetzung bestehender Konzepte, Fortschreibung und Beendigung.

A comprehensive understanding of physical and chemical processes at biological membranes requires the knowledge of the interfacial electric field which is a key parameter for controlling molecular structures and reaction dynamics. An appropriate approach is based on the vibrational Stark effect (VSE) that exploits the electric-field dependent perturbation of localized vibrational modes. In this work, 6-mercaptohexanenitrile (C5CN) and 7-mercaptoheptanenitrile (C6CN) were used to form self-assembled monolayers (SAMs) on a nanostructured Au electrode as a simple mimic for biomembranes. The C - N stretching mode was probed by surface enhanced infrared absorption (SEIRA) spectroscopy to determine the frequency and intensity as a function of the electrode potential. The intensity variations were related to potential-dependent changes of the nitrile orientation with respect to the electric field. Supported by electrochemical impedance spectroscopy, molecular dynamics simulations, and quantum chemical calculations the frequency changes were translated into profiles of the interfacial electric field, affording field strengths up to 4 × 108 V/m (C6CN) and 1.3 × 109 V/m (C5CN) between +0.4 and 0.4 V (vs Ag/AgCl). These profiles compare very well with the predictions of a simple electrostatic model developed in this work. This model is shown to be applicable to different types of electrode/SAM systems and allows for a quick estimate of interfacial electric fields. Finally, the implications for electric-field dependent processes at biomembranes are discussed. Fil: Staffa, Jana K.. Technishe Universitat Berlin; Alemania Fil: Lorenz, Lisa. Technishe Universitat Berlin; Alemania Fil: Stolarski, Michael. Technishe Universitat Berlin; Alemania Fil: Murgida, Daniel Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Zebger, Ingo. Technishe Universitat Berlin; Alemania Fil: Utesch, Tillmann. Technishe Universitat Berlin; Alemania Fil: Kozuch, Jacek. Technishe Universitat Berlin; Alemania Fil: Hildebrandt, Peter. Technishe Universitat Berlin; Alemania

Fur eine elektrische und thermische Optimierung von Hochvolt‐Batterien werden Simulationsmodelle benotigt. Der hier vorgestellte demokratische Optimierungsalgorithmus stellt hohe Anforderungen an die verwendeten Simulationsmodelle. Die wichtigsten Anforderungen bestehen in einer verhaltnismasig hohen Simulationsgeschwindigkeit bei einer geeigneten Modellgute.

The triple-helical structure of a model collagen peptide possessing azobenzene-derived clamps integrated in all three strands as side-chain-to-side-chain crosslinks is analyzed by IR spectroscopy in comparative thermal excursion experiments with the triple helix of a typical reference collagen peptide consisting of only glycine-proline-hydroxyproline repeats. By exploiting the known stabilizing effects of aqueous alcoholic solvents on the unique collagen fold, deuterated ethylene glycol/water (1:1) is used as a solvent to investigate the effect of the light-switchable trans/cis-azobenzene clamp on the stability of the triple helix in terms of H/D exchange rates and thermal unfolding. Results of this comparative analysis clearly reveal only a minor destabilization of the triple helix by the hydrophobic azobenzene moieties compared to the reference collagen peptide as reflected by a lower midpoint of the thermal unfolding and higher rates of H/D exchange. However, it also reveals that the driving force exerted by the trans-to-cis photoisomerization of the azobenzene moieties is insufficient for unfolding of the compact triple-helical collagen fold. Only temperature-dependent untightening of this fold with heating results in a reversible photomodulated unfolding and refolding of the azo-collagen peptide into the original triple helix.

The photochemistry of the fluorescent Pigment Yellow 101 (P.Y.101) in the crystalline phase is investigated combining time resolved vibrational and electronic spectroscopy. The experiments reveal a complex reaction dynamics spanning several orders of magnitude in time and including excited state intramolecular proton transfer (ESIPT) from the initial trans -diol conformer. Following photoexcitation and the subsequent wavepacket motion out of the Franck–Condon region two tautomers, an excited trans -diol and trans -keto state are formed. The cis–trans isomerization of the keto form, which was experimentally observed and theoretically confirmed in DFT calculations in studies on P.Y.101 in solution is obstructed in the solid state, consequently the formation of the cis conformer is not directly observed. In addition, a long lived photoproduct with red shifted vibrational frequencies is identified. The life time of this intermediate is determined to be 50 μs, although an unambiguous assignment to a specific molecular configuration cannot be given at present.

Trans/cis isomerization of a specially designed collagen sample with an azobenzene clamp is examined by time-resolved spectroscopy. The bistable functionality of the azobenzene switch is conserved upon covalent attachment to the peptide, making this model collagen molecule suitable for investigating tertiary structure formation.

=OH)revealsanunexpectedbehavior:Pigments1and3donotfluoresce,neitherinsolutionnorinthesolidstate.However,pigment4 doesexhibitfluorescencelike2both in solution and in the solid state(Table1).This is remarkable for two reasons:1)Compounds2 and4 arefluorescentincontradictiontoanempiricalrulethatstatesthatpigmentswithOHgroupsusuallydonotfluoresce.Here,onlythepigmentswithOHgroupsexhibitfluorescence.2)The fluorescent pigments remainfluorescent upon crystallization,althoughcompound4 displaysshortintermoleculardistancesinthecrystal,which should lead to fluorescencequenching.

IN 1944, Smith and Hale1 showed that the clotting of fibrinogen by coagulase depends on an activator present in the plasma of certain animals, notably humans and rabbits. Since a fibrinogen–prothrombin complex prepared from human plasma by Mellanby's2 acid precipitation method, which could be clotted by tissue kinase, could not be clotted by coagulase, they concluded that the activator was not prothrombin. Later, Tager3 and Tager and Hales4 noted certain resemblances between the physical properties of activator and prothrombin, both being precipitated with the globulin fractions in the region of pH 5.0 and by 50 per cent saturation with ammonium sulphate. In ethanol-precipitated fractions of plasma prepared by the method of Cohn5, activator was present in fractions III-1, III-2 and IV-1, whereas prothrombin is believed to occur only in III-2. Both prothrombin and activator were absorbed from plasma by barium sulphate; but considerable dissociation followed repeated Seitz filtration of human plasma, prothrombin activity being lost without comparable loss of activator. Studies by Kaplan and Spink6 disagreed with these findings, inasmuch as they found activator to be associated with the albumin fraction in ammonium sulphate fractionation, and to lie mainly in IV-4 of the ethanol precipitate.