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Einleitung: Die COVID-19-Pandemie hatte starke Auswirkungen auf die Arbeit von traumatologischen Teams. Ziel der Studie war es, die Inzidenz der Schockräume (SR) und die Traumamechanismen vor und während der Pandemie in einem Traumazentrum der Stufe I zu vergleichen. Ziel der Arbeit: Die Beobachtung der Auswirkungen der COVID-19-Pandemie auf das Aufkommen von Schwerverletzten im Sinne der SR-Inzidenz vor und während der Pandemie. Material und Methoden: Krankenakten aller SR-Patienten von März 2019 bis Februar 2021 wurden analysiert. Inzidenz- und Traumamechanismen der 12 Monate vor und der 12 Monate während der Pandemie wurden verglichen. Traumaverteilung und -grad wurden mittels AIS und ISS beschrieben, und das Heimatland der Patienten wurde erfasst. Ergebnisse: Die SR-Fälle gingen von 694 vor der COVID-19-Pandemie auf 477 Fälle während der Pandemie zurück (Inzidenzrate 0,69). Der stärkste Rückgang der Traumata war bei Sportverletzungen (0,55) zu verzeichnen, gefolgt von Suizidversuchen (0,63), Verkehrsunfällen (0,71) und Freizeitunfällen (0,76). Die Rate der Patienten mit schweren Verletzungen (ISS ≥ 16) war vergleichbar mit 40 % vor der Pandemie und 44 % während der Pandemie. Der Anteil an SR-Patienten aus dem Heimatland erhöhte sich von 63 auf 84 %. Die Zahl ausländischer Patienten wurde während der Pandemie signifikant reduziert (257 vs. 77). Diskussion: Die SR-Inzidenz ging während der Pandemie durch die verhängten Lockdowns während der Winterhochsaison signifikant zurück. Die Rate der ausländischen SR-Patienten hat sich während der Pandemie verändert, während die Rate der Schwerverletzten stabil geblieben ist. Graphic abstract:

The lacrimal drainage system is known not as a straight but winding mucosal passage. Lang (1979) reports certain bends and angles of the bony nasolacrimal canal. the aim of this study was to quantify the bends of the nasolacrimal canal in macerated skulls. the lower orifice of the nasolacrimal canal beneath the inferior concha was closed by means of bone wax. Afterwards, epoxy resin containing finely dispersed Bismuth-(III)-oxide was used to fill the bony canal from its upper opening. Standardized radiographs were taken of these specimens before removing the bony structures surrounding the epoxy resin casts of the nasolacrimal canal. the isolated casts were photographed from a frontal and lateral aspect. the angles were then measured and used for a trigonometric construction of the maximal curvature of the nasolacrimal canal.Detailed measurements will be reported. As a main result, a dorsomedial curvature of the nasolacrimal canal was found in most cases, showing a considerable variation in its angle. the clinical implications will be discussed.

Teasing preparations of cat extraocular muscles (EOM) were used to study the arrangement of muscle fibers and the distribution of the different cholinesterase-positive sites, i.e. (1) large motor endplates, (2) small motor endings of the “en grappe” type, (3) myotendinous junctions and (4) myomyous junctions. The distribution of these cholinesterase-positive structures gives clear evidence of a complex muscle architecture of cat EOM. In the global layer of cat EOM, only multiply innervated muscle fibers run the whole length of the muscle. The focally innervated muscle fibers are generally shorter; they are usually arranged in series of two to three fibers being interconnected by myomyous junctions. Moreover, muscle fiber splitting is frequently present resulting in a netlike arrangement of muscle fibers. Most of the myomyous junctions occur between focally innervated muscle fibers, but also end-to-side connections of focally to multiply innervated muscle fibers are observed; multiply innervated muscle fibers have not been found connected to each other. In this layer, large motor endplates are distributed in several bands between origin and insertion. In the orbital layer all muscle fibers run from tendon to tendon, focally as well as multiply innervated ones. Here, large motor endplates are confined to a band in the middle of the muscle, and myomyous junctions are generally absent.

The changes of cell nuclear size were studied by means of a semiautomatic measuring instrument (Zeiss TGZ 3) in 8 organs of rats 15 days after hypophysectomy. The organs of normal animals sacrificed at the beginning and at the end of the 15 day experiment were used as controls. In further animals sham-hypophysectomies were performed; and the organs of these animals were examined on the 4th and on the 15th postoperative day. By means of statistical methods (t-test, variance analysis) it could be demonstrated that in all organs of the hypophysectomized animals the diameters of the cell nuclei differ significantly from those of the control groups. According to whether the organs are directly or indirectly dependent on the pituitary gland, the diameters of the cell nuclei showed a decrease between 0.6 and 16% of their normal values. The juxtaoral organ, the function of which is still unknown, showed the most pronounced decrease (-16%) of its nuclear diameter. This fact supports the hypothesis of the authors that the juxtaoral organ belongs to the group of endocrine glands dependent on the pituitary gland.

A new method to stabilize a vehicle, which is autonomously guided on the road by an optical sensor, is presented. Since the behavior of a vehicle is nonlinear and contains mutual couplings in the dynamical variables, the design especially of algorithms for transverse control is based on the universal valid principle of feedback linearization. This method works independently from any operating point and, thus, a high degree of accuracy and free pole assignment for the overall system is provided. The design of the control system is based on absolute angular velocities. A strategy transforming these variables into a relative system by an adequate transformation is described. Thus, the control error of the angle describing the direction of movement is forced to disappear. As all essential nonlinearities in the dynamics of the vehicle body, the wheels and the tyres are compensated, a linear behavior with free pole assignment can be imposed on the overall system. Disturbances are handled by an integral term in the control algorithm. Therefore stability and convergence can be guaranteed even in case of constant disturbances.

Two different control methods are presented, which stabilize an automatically guided vehicle on a desired path on the road by influencing its steering angle. However, instead of controlling the path of the vehicle’s centre of gravity, the path of a fictitious point, which is located on the longitudinal axis in front of the centre of gravity and, thus, outside the vehicle’s geometry, is navigated. This special configuration causes a significant damping effect of the yaw behaviour during high speed cornering. The control system, which is presented first, is designed in absolute coordinates based on an inertial coordinate system. The second control system represents a practical application based on the results of this configuration, where the algorithms are designed regarding relative coordinates. Then, the actual position of the fictitious point can be easily determined by an optical sensor system, which is mounted on the car and, thus, subsequently the measured values can be fed back into the control module.

An optimal control strategy for combined sewer network control is formulated and tested with respect to several practical aspects like sensitivity to changing performance indices and different sample time intervals, impact of simplifications and inaccurate inflow predictions, and role of the optimization time horizon. Furthermore performance of the method is investigated for a broad class of inflow events and is compared to heuristic strategies. Results demonstrating the ability of the proposed strategy to handle the complex combined sewer network control problem are presented and discussed.

The sensory apparatus of the extraocular muscles attains special interest because of the great variation among different species with respect to the proprioceptors. The sensory innervation of the guinea pig extraocular muscles, lacking both muscle spindles and tendon organs, was investigated with a fluorescence double‐labelling method. Primary sensory perikarya were assessed by postmortem application of 1,1′‐dioctadecyl‐3,3,3′3′‐tetramethylindocarbocyanine perchlorate (Di‐I) to the extraocular muscle nerves. Traced neurons were found in the ipsilateral ophthalmic part of the trigeminal ganglion. This is in line with findings in other species. Calcitonin gene‐related peptide (CGRP) was detected immunohistochemically within the trigeminal ganglion. No somatotopic organization was observed for CGRP‐like immunoreactive perikarya. Small (maximal diameter below 30 μm), medium (maximal diameter between 30 and 50 μm), and large (maximal diameter larger than 50 μm) trigeminal ganglion cells were found among the primary afferent perikarya from extraocular muscles. Among CGRP‐like immunoreactive cells, only small and medium cells were observed. Double‐labelling experiments indicated the CGRP content of primary afferents of the guinea pig extraocular muscles. The relationship to former morphological categories of ganglion cells is discussed. Primary afferent neurons with CGRP‐like immunoreactivity might have efferent functions and might also be involved in inflammatory processes of extraocular muscles. J. Comp. Neuol. 380:16–22, 1997. © 1997 Wiley‐Liss, Inc.

A new method to stabilize a vehicle, which is autonomously guided on the road by an optical sensor, is presented. Since the behavior of a vehicle is nonlinear and contains mutual couplings in the dynamical variables, the design of the algorithms for lateral control is based on the universal valid principle of feedback linearization. This method works independently from any operating point and, thus, a high degree of accuracy and free pole assignment for the overall system is provided. The design of the control system is based on absolute angular velocities. A strategy transforming these variables into a relative system by an adequate transformation is described. A linear behavior with free pole assignment can be imposed on the overall system and disturbances are handled by an integral term in the control algorithm. Therefore stability and convergence can be guaranteed even in case of constant disturbances.

Autonomous intelligent cruise control design is a very important aspect of automation systems in future traffic patterns. A strategy for automated vehicle tracking is described, which keeps a velocity-dependent distance between the vehicles in order to provide a constant time-headway. As it is based on the principle of feedback linearization, highly structured and organized algorithms can be provided, without using special preferred operating points. Essential nonlinearities are compensated for in a direct way, and an arbitrary linear behaviour can be imposed on the remaining system. In order to provide a fast transient behaviour and insensitivity to disturbances, the control laws include, besides a proportional part, derivative as well as integral terms. Furthermore, the system is prevented from having an overshoot, and comfort parameters can be adjusted. Owing to its high performance, this control system directly contributes to the enhancement of traffic safety.

In this work, a new method to stabilize a vehicle, which is autonomously guided on the road by an optical sensor, is presented. Since the behaviour of a vehicle is nonlinear and contains mutual couplings in the dynamical variables, the design especially of algorithms for transverse control is based on the universal valid principle of feedback linearization. This method works independently from any operating point and, thus, a high degree of accuracy and free pole assignment for the overall system is provided. The design of the control system is based on absolute angular velocities. A strategy transforming these variables into a relative system by an adequate transformation is described. Thus, the control error of the angle describing the direction of movement is forced to disappear. As all essential nonlinearities are compensated, a linear behaviour with free pole assignment can be imposed on the overall system. Disturbances are handled by an integral term in the control algorithm. Thus, stability and convergence can be guaranteed even in the case of constant disturbances.

In earlier histochemical, biochemical and radiochemical examinations several enzymes (Mg-activated ATPase, Succinodehydrogenase and DPNH-Diaphorase) were found to occur in reduced quantities in the extraocular muscles of squinting eyes.

The juxtaoral organ of adult human is investigated by means of electron microscopy.

After staining of the motor nerve endings with a cholinesterase technique and of nerve and muscle fibers with Sudanschwarz B, single muscle spindles were isolated from lumbrical muscles of rats and examined by means of light microscopy.

In skeletal muscle fibers of birds, connections without interposition of tendinous material were found. The cellular membranes of the connected muscle fibers come into contact with each other in an indented line. The space between the two membranes measures 700 to 1600 Å and is filled with basement membrane-like material showing cholinesterase activity and lacking any connective tissue fibers.

In a rat muscle spindle transversally cut into a series of alternating semithin and ultrathin sections, two different forms of nerve terminations were found on two neighbouring nuclear chain fibres. The two nerve terminations were connected to the same group II nerve fibre and are consequently constituents of one particular secondary sensory ending.

In addition to a light-microscopical investigation of the external eye musculature of the Rhesus monkey (Zenker and Anzenbacher, 1964) the following differences between muscle fibres innervated by single and those innervated by multiple myoneural synapses were found by means of electron microscopy:1.The myofibrils of single innervated fibres are usually surrounded by relatively broad zones of sarcoplasmic reticulum, whereas in multiple innervated fibres individual myofibrils can hardly be demarcated.2.Mitochondria are abundant in single innervated fibres; they differ considerably in size and are irregularly arranged. The generally much smaller mitochondria of multiple innervated fibres are remarkably regularly arranged.3.The sarcomeres of single innervated fibres are about 19% longer than those of multiple innervated fibres.4.The Z-disc of multiple innervated fibres is wider than that of single innervated ones. Neither a M-band nor a pseudo-H-zone could be detected in multiple innervated fibres.5.In the ample sarcoplasmic reticulum of the single innervated fibres Porter's triades are far more frequent than in multiple innervated ones, in which the triades are found in quite different parts of the muscle fibre.6.Nerve fibres which approach the synapses of the multiple innervated fibres are more than half as thin than those which belong to the motor end-plates of the single innervated muscle fibres. The latter retain their myelin sheaths until they reach the end-plate region. They release unmyelinated terminal branches either at Ranvier's nodes, which appear there at short intervals, or at the thickened ends of the nerve.