Search results for "FORCE"
showing 10 items of 3423 documents
Symptom variability and control in COPD: Advantages of dual bronchodilation therapy
2017
Abstract Background Chronic obstructive pulmonary disease (COPD) is a heterogeneous disorder characterized by usually progressive development of airflow obstruction that is not fully reversible. While most patients will experience symptoms throughout the day or in the morning upon awakening, many patients do not experience their symptoms as constant but report variability in symptoms during the course of the day or over time. Symptom variability adversely affects patients' health status and increases the risk of COPD exacerbations. Methods We examined data from the literature on symptom variability and control in patients with COPD, with focus on the use of inhaled bronchodilator therapy wi…
Freedom and Enforcement in Action : A Study in Formal Action Theory
2015
Neuromuscular and mobility responses to a vibration session in hypoxia in multiple sclerosis
2020
AbstractThe aim of this study was to investigate the acute effects of vibration training (WBVT) under hypoxic and normoxic conditions on the voluntary rate of force development (RFD), balance and muscle oxygen saturation (SMO2) in persons with Multiple Sclerosis (MS). 10 participants completed the study (30% males, 44.4±7.7 years, 164.3±8.9 cm, 65.2±11.1 kg, 2.5±1.3 Expanded Disability Status Scale, 24.1±4.0 kg.m−2 BMI). Maximal force, RFD during isometric knee extension, static balance with eyes open and closed and sit-to-stand test were evaluated before and immediately after one session of WBVT (12 60-s bout of vibration; frequency 35 Hz; amplitude 4 mm; 1-min rest intervals) under both n…
Derivatisation of Pyrogallarenes
2005
Derivatisation of upper-rim hydroxy groups of pyrogallarenes produced completely acylated and tosylated pyrogallarene derivatives. Mesitylation of pyrogallarene, however, resulted in a regioselective derivatisation of hydroxy groups, i.e. eight OH groups out of 12 were mesitylated. Crystal structures of the synthesised pyrogallarene derivatives indicate that completely substituted pyrogallarenes exist in a distorted crown conformation despite of the lack of stabilising intramolecular hydrogen bonds. In contrast, the partially substituted pyrogallarene adopts a boat conformation and has an open cavity for the inclusion of small guest molecules. © Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinh…
ChemInform Abstract: A General Overview of the Organocatalytic Intramolecular Aza-Michael Reaction
2015
The organocatalytic intramolecular aza-Michael reaction gives access to enantiomerically enriched nitrogen-containing heterocycles in a very simple manner. Enals, enones, conjugated esters and nitro olefins have been employed as Michael acceptors, while moderate nitrogen nucleophiles such as sulphonamides, carbamates and amides have been shown to be appropriate Michael donors in this type of reaction. Additionally, the process has been performed under both covalent and non-covalent catalysis, with diaryl prolinols, imidazolidinones, thioureas and chiral binol phosphoric acids being the most frequently used catalysts. The level of efficiency reached with this protocol is demonstrated by the …
ChemInform Abstract: Synthesis of 2-Isoxazolines: Enantioselective and Racemic Methods Based on Conjugate Additions of Oximes.
2011
Acidic anilinium salts catalyze the direct formation of racemic 2-isoxazolines from enals and oximes by means of consecutive oxime conjugate-addition and intramolecular oxime-transfer reaction.
Measuring single small molecule binding via rupture forces of a split aptamer.
2011
The rupture force of a split (bipartite) aptamer that forms binding pockets for adenosine monophosphate (AMP) was measured by atomic force spectroscopy. Changes in the rupture force were observed in the presence of AMP, while this effect was absent when mutant aptamers or inosine were used. Thus, changes in the rupture force were a direct consequence of specific binding of AMP to the split aptamer. The split aptamer concept allowed the detection of nonlabeled AMP and enabled us to determine the dissociation constant on a single-molecule level.
La mesure directe des forces de liaison entre les hydrates appliquée à la prise de plâtre
1998
Le phenomene de prise est un phenomene general, observable sur tous les liants mineraux, ciments siliceux, alumineux... et le plâtre. S'il existe des lois gouvernant la prise, elles doivent s'appliquer a tous ces liants. Aussi, il peut etre justifie de prendre tel ou tel liant pour modele si cela peut simplifier la premiere approche. Ici, l'objectif est de mesurer les forces entre les grains de silicate de calcium hydrate (phase C-S-H) qui est l'hydrate le plus caracteristique des ciments courants. Ces grains sont extremement petits et il a ete choisi de mettre au point les methodes travaillant sur le plâtre qui s'hydrate sous forme de gypse en formant des cristaux de 10 a 100 fois plus gro…
Numerical simulations demonstrate that the double tapering of the spatualae of lizards and insects maximize both detachment resistance and stability
2011
Many biological attachment devices of insects, spiders and geckos consist of arrays of hairs (setae), which are terminated by contact elements of different shapes. However, the most frequently observed shape is a thin plate-like spatula. In spite of a rather wide range of sizes, most spatulae of different animals are not uniform, but rather possess a gradient in thickness and width. Here we show that the spatulae of insects and geckos become gradually thinner and wider approaching the end. This geometrical effect is explained in the present paper, by using a numerical approach for the modelling of the van der Waals adhesion and friction between the contact elements and the substrate. The ap…
Signal Characteristics of EMG at Different Levels of Muscle Tension
1976
Electromyographic activity of m. rectus femoris at submaximal and maximal voluntary contractions was quantified by conventional integration technique and also be a more "qualitative" procedure of automated motor unit averaging and frequency spectrum analysis. By relating the EMG parameters to produced muscle tension it was observed that the integrated EMG increased in a slightly nonlinear fashion with the increase in muscle force. The other EMG variables also showed clear changes as a function of muscle tension. The averaged motor unit potential (AMUP) and its specific parameters (number of spikes, amplitude, rise time and amplitude-rise time ratio) showed such changes with muscle tension t…