PDM for the enterprise
Mechanical engineering (New York, N.Y. 1919),
10/1998, Letnik:
120, Številka:
10
Magazine Article
Companies are focusing on building product data management (PDM) systems from the ground up using Internet and related technologies. Perhaps the most notable example of the trend is Windchill from ...Parametric Technology Corp. In an interview, James Heppelmann, senior vice president responsible for Windchill and PTC's overall information technology strategy, explained what has changed in manufacturers' competitive environment and how the new enterprise-wide PDM systems fit in this new landscape.
The noncorpuscular endings ("free nerve endings") of thinly myelinated group III and nonmyelinated group IV afferent nerve fibers have been examined in the knee joint capsule of sympathectomized cats ...by transmission electron microscopy and three-dimensional reconstruction of series of semi- and ultrathin sections. The sensory ending is the most distal part of a group III or IV nerve fiber that consists only of the sensory axon and associated Schwann cells but lacks a myelin sheath and is not surrounded by perineurium. The sensory axon divides into several branches and forms a terminal tree. The branches run either as single fibers or within small Remak bundles in parallel to sensory axons of other endings; they spread along vessel walls and also extend into dense connective tissue. Each sensory axon consists of a series of spindle-shaped thick segments ("beads") connected by waist-like thin segments. Thus all axons of sensory endings have a string-of-beads appearance, which resembles that of efferent sympathetic nerve fibers. The beads of the sensory axon and the end bulb at its tip show the same ultrastructural features which are characteristic of receptive sites: an accumulation of mitochondria and glycogen particles and various vesicles in the axoplasm and "bare" areas of axolemma that are not covered by Schwann cell processes. Group III and group IV sensory endings differ in the length of their branches (up to 200 microM in group III vs. more than 300 microM in group IV), number of beads per 100 microM axon length (about seven vs. nine or ten), mean diameter of axons (0.9-1.5 microM vs. 0.3-0.6 microM), and the presence of a neurofilament core consisting of bundles of parallel microfilaments only in group III. In conclusion, we propose that the sensory part of noncorpuscular "free nerve endings" is formed by the entire terminal tree of group III or group IV nerve fibers and that the beads in the course of the sensory axon represent multiple receptive sites.
The importance of renewable energy resources are growing because of many reasons including the increasing costs of fossil fuels and the growing awareness of sustainability and environmental concerns. ...There are many different possibilities to use renewable energy systems in the domestic housing sector like photovoltaic for electrical power or solar collectors for thermal energy to provide space heating and hot water. Moreover there are more heat pump systems on the market using a borehole to upgrade the thermal energy and use it efficiently in heating systems. It is clear that individual house owners should install renewable energy systems such as solar-assisted heat pumps if they are to assist in contributing to reducing primary fossil fuels and CO 2 emissions as agreed at the Kyoto summit. Significant research has been carried out in the field of solar-assisted heat pump system since the 70s but most of the technologies developed have stayed at the research level due to two primary reasons, namely poor control strategies and the inability to keep operating temperatures high enough to realize high coefficients of performance over the full year. Within the frame of the EC funded Endohousing project these issues are being investigated. The research focuses on the development of an in innovate technology that comprising integrating large unglazed solar roof collectors coupled to a heat pump whose operation is controlled via hi-tech control strategies to manage the movement of thermal energy effectively in different sections of the system. The project has set up five demonstration systems using the endothermic technology. This paper is concerned with the setting up, commissioning and run in of the various systems and an initial evaluation of the results that have been obtained to date for space heating, cooling and seasonal storage
The peripheral and central terminals of primary afferents of the cat's knee joint were studied with light- and electron microscopy (including HRP-transport methods). The majority of these afferent ...fibres are unmyelinated or thinly myelinated. In the periphery, they terminate in non-corpuscular endings. A dense network of branching nerve fibres surround the blood vessels to terminate at the vessel walls or in the adjacent dense collagenous tissue. Besides the terminals the fibres show preterminal bulges which are assumed to represent additional transduction sites. This implies that the whole distal fibre portion has a receptive function. The spinal projection is located in lamina I and V-VII of the dorsal horn. This location parallels that of muscular and visceral fibres, pointing to the possibility of a common projection pattern for deep somatic afferent fibres in the spinal cord of the cat.
The applicability of the 5-brom-3-indolyl-alpha-ketoside of N-acetyl-D-neuraminic acid (BI-NeuAc) as substrate for the histochemical indication of neuraminidase (GOSSRAU et al. 1977) was examined in ...frozen sections of brain, small intestine and kidney from suckling and adult mice and respectively from a cichlid fish (Sarotherodon mosambicus) with and without formaldehyde fixation. Following biochemical investigations using tritiated gangliosides as substrate a decrease in the activity of neuraminidase took place from about 50 to 80% after tissue fixation with formaldehyde. Nevertheless significant histochemical reactions were found only in fixed tissue sections. The specificity of this reaction was shown by means of inhibitions tests using 2,3-dehydro-2-desoxy-N-acetyl-neuraminic acid according to KUMAR et al. (1981). In contrast to distinct staining of neuraminidase activity in the small intestine and kidney, only faint reactions occurred in brain sections. From this it is concluded that the application of the new synthetic substrate for quantitative staining of neuraminidase seems to be not very suitable for the CNS.
The "mild" periodic acid-thionine (mPAT)-method was examined for the quantitative research of histochemical localization of sialic acid (NeuAc)-containing compounds in brain samples of goldfish and ...albino mice in comparison to salivary gland (Glandula submandibularis) of the mouse. Biochemical determinations of NeuAc contents of the tissues showed that during histological treatment a significant decrease in the amount of lipid-bound NeuAc, especially in the brain had occurred, because of its high content of lipid-bound NeuAc. A previous KOH-treatment caused in an increase of the colour reaction, which indicated mainly the amount of O-acylated NeuAc just as possibly lactone containing NeuAc-compounds. The intensity of staining, especially in the optic tectum of goldfish, decreased to 45% after neuraminidase-treatment. The low concentration of NeuAc-compounds in the brain in comparison to the salivary glands, results in only a faint staining. Therefore, the use of the mPAT-method seems to be not very suitable for a specific and quantitative staining of all NeuAc-compounds in the CNS.
Purpose of this study was the evaluation of distribution and morphology of mechanoreceptors in the glenohumeral joint capsule and rotator cuff in comparison to the coracoacromial ligament by means of ...specific immunfluorescence microscopy. The complemente joint capsules, rotator cuffs and coracoacromial ligaments of three fresh cadaver shoulder were harvesed. Serial cryostate sections were taken and alternately incubated with antiserum against neurofilament, lamin or myelin of peripheral nerves. The antibody-reaction was visualized with fluorescin lg-G. The nerve endings were photographed and computer-aided 3-dimensional reconstructions were performed. Three types of corpuscular and free nerve endings of different morphology were found in different distributions: whereas the Ruffini corpuscles were much more frequent in the coracoacromial ligament and rotator cuff, Pacini endings were predominantly found in the joint capsule. Generally corpuscular nerve endings were more frequent in the coracoacromial ligament and the rotator cuff than in the antero-inferior capsule and the number of corpuscles increased from medial to lateral within the anterior and inferior parts of the capsule. The dense ligamentous tissue was almost aneural whereas the periarticular fatty or loose connective tissue contained nerve fibres and nerve endings. In view of the results of other experimental and clinical studies the high frequency of Ruffini and Pacini endings in the rotator cuff and coracoacromial ligament suggest, that both are involved in the neurosensory control of glenohumeral stability and subacromial impingement. In contrast our findings in the joint capsule do not clearly prove, that those joint receptors predominantly maintain joint stability.
Nucl.Phys.B420:565-582,1994 We show how the transverse polarization of a quark initiating a jet can be
probed by the azimuthal distribution of two hadrons (of large $z$) in the jet.
This permits a ...twist 2 asymmetry in hard processes when only one of the initial
particles is polarized transversely. Applications to hadron-hadron and
lepton-hadron scattering are discussed.
