Optimal inertial sensor location for ambulatory measurement of trunk inclination

Trunk inclination (TI) is used often to quantify back loading in ergonomic workplace evaluation. The aim of the present study was to determine whether TI can be obtained using a single inertial sensor (IS) on the back, and to determine the optimal IS location on the back for the estimation of TI. Gold standard TI, the angle between the vertical and the line connecting the L5/S1 joint and the trunk centre of mass, was measured using an optoelectronic system. Ten subjects performed experimental trials, each consisting of a symmetric and an asymmetric lifting task, and of a left–right lateral flexion movement. Trials were repeated and, in between trials, the IS was shifted in small steps from a location on the thorax towards a location on the sacrum. Optimal IS location was defined as the IS location with minimum root-mean-square (RMS) error between the gold standard TI and the IS TI. Averaged over subjects, the optimal IS location for symmetric and asymmetric lifting was at about 25% of the distance from the midpoint between the posterior superior iliac spines (MPSIS) to the C7 spinous process. The RMS error at this location, averaged over subjects, was 4.6±2.9°. For the left–right lateral flexion task, the optimal IS location was at about 30% of the MPSIS to C7 distance. Because in most activities of daily living, pure lateral flexion does not occur often, it is recommended place the IS at 25% of the distance from the MPSIS to C7.     

Sensitivity of microbial lipases to acetaldehyde formed by acyl-transfer reactions from vinyl esters

Summary The sensitivity of twenty six microbial lipases towards acetaldehyde (an unavoidable by-product in lipase-catalysed acyl transfer reactions with vinyl esters) was investigated. The sensitivity of an individual enzyme strongly depends on its properties such as microbial source, molecular weight and relative lysine content. Whereas the majority of enzymes (from Pseudomonas, Rhizopus, Chromobacterium, Mucor and Candida antarctica sp.) proved to be remarkably stable, lipases from Candida rugosa and Geotrichum candidum lost most of their activity when exposed to acetaldehyde.     

Determination of biological activity of 24,24-difluoro-1,25-dihydroxyvitamin D3 in the chick using a new method for assessing intestinal calcium uptake

Oxygen-dependent calcium uptake by chick duodenal discs has been characterized and used to assay the relative activities of 1,25-dihydroxyvitamin D₃ and its 24,24-difluoro analog. The calcium uptake was found to be stimulated by low sodium (30 mm) and phosphate (0.01–0.3 mm). The rate of oxygen-dependent calcium uptake was found half-maximal at a calcium concentration of 5 mm. At a concentration of 5 mm calcium, the uptake was linear for at least 15 min with approximately a threefold stimulation by prior administration of 1,25-dihydroxyvitamin D₃ (125 ng). This determination, as well as increase in serum calcium and percentage bone ash, was used to assess the biological activities of 1,25-dihydroxyvitamin D₃ and its 24,24-difluoro analog. The difluoro analog is about four to five times more active than 1,25-dihydroxyvitamin D₃ as measured in each of these systems.     

Non-extensitivity and criticality of atomic hydropathicity around a voltage-gated sodium channel’s pore: a modeling study

Voltage-gated sodium channels (NavChs) are pore-forming membrane proteins that regulate the transport of sodium ions through the cell membrane. Understanding the structure and function of NavChs is of major biophysical, as well as clinical, importance given their key role in cellular pathophysiology. In this work, we provide a computational framework for modeling system-size-dependent, i.e., cumulative, atomic properties around a NavCh’s pore. We illustrate our methodologies on the bacterial NavAb channel captured in a closed-pore state where we demonstrate that the atomic environment around its pore exhibits a bi-phasic spatial organization dictated by the structural separation of the pore domains (PDs) from the voltage-sensing domains (VSDs). Accordingly, a mathematical model describing packing of atoms around NavAb’s pore is constructed that allows—under certain conservation conditions—for a power-law approximation of the cumulative hydropathic dipole field effect acting along NavAb’s pore. This verified the non-extensitivity hypothesis for the closed-pore NavAb channel and revealed a long-range hydropathic interactions law regulating atom-packing around the NavAb’s selectivity filter. Our model predicts a PDs-VSDs coupling energy of ∼282.1 kcal/mol corresponding to a global maximum of the atom-packing energy profile. Crucially, we demonstrate for the first time how critical phenomena can emerge in a single-channel structure as a consequence of the non-extensive character of its atomic porous environment.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10867-021-09565-w.     

Die Entstehung und experimentelle Beeinflussung des extremen Geschlechtsunterschieds im Wachstum der Moschusente,Cairina Moschata Flemm

Ohne ZusammenfassungDie Arbeit wurde ermöglicht durch die großzügige Unterstützung des Ehrensenators der Landwirtschaftlichen Hochschule Hohenheim Herrn Dr. Ing. e.h.Karl F.Nägele. Ihm gilt mein besonderer Dank.     

Die läutausserungen der orthopteren. (Lauterzeugung,läutabwandlung und deren biologische bedeutung sowie tonapparat der geradflügler.) Vergleichende untersuchungen I

Ohne Zusammenfassung