Search results for "Absolute"

Prolin-benzylester als chirale Hilfsgruppen in asymmetrischen 1,3-dipolaren Cycloadditionen mit Nitriloxiden

1990

Proline Benzyl Esters as Chiral Auxiliaries in Asymmetric 1,3-Dipolar Cycloadditions N-Acryloylproline benzyl ester (1b) reacts with nitrile oxides at temperatures from −78 to 0°C to give isoxazolines 4/5 with diastereomeric ratios of ca. 3:1 and with the (5S) isomer as the predominating. The corresponding N-methacryloylproline benzyl ester (1c) gives inferior results. The diastereoselectivity is not influenced by the temperature and the substituents of the nitrile oxides. To prove the absolute configuration of the predominating stereoisomer, a reaction sequence is developed which makes use of an enantioselective hydrolysis with pig liver esterase as the key step to generate an optically ac…

Current transformers effects on the measurement of harmonic active power in LV and MV networks

2011

The harmonic active power is used to determine the location of polluting loads, the direction of harmonic power flow and to estimate how consequential a certain current harmonic source is. The highest uncertainties, when measuring harmonic active power, are introduced by the current and voltage transducers. This paper presents experimental results which show the impact of current transformers (CTs) on the accuracy of the harmonic power measurements. An expression for the evaluation of the power error in distorted conditions was developed which can be easily utilized in the case of linear current transducers. It is shown how CTs cannot be considered linear transducers and how the higher the …

Approximation of pre-twisted Achilles sub-tendons with continuum beam elements

2022

Achilles sub-tendons are materially and geometrically challenging structures that can nearly undergo around 15% elongation from their pre-twisted initial states during physical activities. Sub-tendons' cross-sectional shapes are subject-specific, varying from simple to complicated. Therefore, the Achilles sub-tendons are often described by three-dimensional elements that lead to a remarkable number of degrees of freedom. On the other hand, the continuum-based beam elements in the framework of the absolute nodal coordinate formulation have already been shown to be a reliable and efficient replacement for the three-dimensional continuum elements in some special problems. So far, that element …

Fabrication, Electrical Characterization and 1/f Noise Study of Submicron-sized Superconducting Tunnel Junctions

2016

Adolescent and Young Adult Cancer Survivors: Design and Characteristics of the First Nationwide Population-Based Cohort in Italy

2020

Purpose: Adolescent and young adult (AYA, 15-39 years) cancer survivors (alive at least 5 years after cancer diagnosis) are less studied than younger and older cancer survivors and research on their late effects is limited. To facilitate research on long-term outcomes of AYA cancer survivors, we established, in Italy, a population-based AYA cancer survivors' cohort. This article describes the study design and main characteristics of this cohort. Methods: The cohort derives from population-based cancer registries (CRs). Each CR identified AYA cancer patients retrospectively. Treatment for first primary cancer and all health events from diagnosis to death can be traced through linkage with av…

Struktur-Wirkungs-Beziehungen bei Histaminanaloga, 18. Mitt. Absolute Konfiguration und histaminartige Wirkung der Enantiomere von 5-Amino-4,5,6,7-te…

1979

Es werden die Racemattrennung von 5-Amino-4,5,6,7-tetrahydro-benzimidazol (3), die Bestimmung der absoluten Konfiguration sowie die histaminartige Wirksamkeit der Enantiomere am Ileum (H1) und Atrium (H2) des Meerschweinchens beschrieben. Structure-Activity Relationship of Histamine Analogues, XVIII: Absolute Configuration and Histamine-like Activity of the Enantiomers of 5-Amino-4,5,6,7-tetrahydrobenzimidazole The resolution of 5-amino-4,5,6,7-tetrahydrobenzimidazole (3), the determination of the absolute configuration and the histamine-like activity of the enantiomers on the guinea-pig ileum (H1) and atrium (H2) are reported.

Stereoselective Synthesis of the Antiprotozoal Lactone Passifloricin A and Seven Isomers Thereof

2004

The conjugated delta-lactone passifloricin A, a natural product with antiprotozoal activity, and seven isomers thereof have been synthesized in enantiopure form. It has been shown in this way that the proposed structure for the natural compound was erroneous. The correct structure is now evidenced. Key steps of the syntheses were asymmetric Brown-type aldehyde allylations and ring-closing metatheses.

Estimating Heart Rate, Energy Expenditure, and Physical Performance With a Wrist Photoplethysmographic Device During Running

2017

BackgroundWearable sensors enable long-term monitoring of health and wellbeing indicators. An objective evaluation of sensors’ accuracy is important, especially for their use in health care. ObjectiveThe aim of this study was to use a wrist-worn optical heart rate (OHR) device to estimate heart rate (HR), energy expenditure (EE), and maximal oxygen intake capacity (VO2Max) during running and to evaluate the accuracy of the estimated parameters (HR, EE, and VO2Max) against golden reference methods. MethodsA total of 24 healthy volunteers, of whom 11 were female, with a mean age of 36.2 years (SD 8.2 years) participated in a submaximal self-paced outdoor running test and maximal voluntary exe…

Verbesserte Auswertbarkeit transitorisch evozierter otoakustischer Emissionen durch Korrelationsfilterung

1993

Hearing screening as well as evaluation of cochlear function under therapy with ototoxic agents or patients with various diseases is increasingly done by registration of transient evoked otoacoustic emissions (TEOAE). Usually the standard system ILO 88 Otodynamic Analyser is used, where until now emissions were analyzed subjectively. However, evaluation of signals may be difficult mainly in the hearing threshold area. In this article we describe a method to mathematically analyze registered emissions by correlation-filtering. This allows to better identify small specific responses, to further increase the sensitivity of TEOAE, and offers a more objective means for audiologic diagnoses.

Efficacy of allergen immunotherapy in reducing the likelihood of developing new allergen sensitizations: a systematic review

2017

Background Guidelines and position papers indicate that allergen immunotherapy (AIT) is the only disease-modifying treatment, including prevention of the onset of new allergen sensitizations. However, this preventive effect was shown by only a few observational studies. Our aim was to systematically review the efficacy of AIT in preventing the onset of new allergen sensitizations. Methods Computerized bibliographic searches of MEDLINE, EMBASE, and the Cochrane Library (through June 2015) were supplemented with manual searches of reference lists. Observational studies or randomized controlled trials with a long-term observation period were included. Paired reviewers extracted data about stud…