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Gear manufacturing always results in some degree of manufacturing errors, i.e. deviations from the desired gear geometry. These errors alter how the gears mesh, typically causing increased contact pressure which in turn shortens service life. It is therefore crucial to choose tolerances such that excessive contact pressure, and especially tip contact, is avoided. With increasing demands due to electrification, this becomes even more important. The aim of this paper is to study how pitch error and profile slope error affect the contact pressure in spur gears sets. The meshing is simulated using a novel simulation approach that uses a parametric description of the reference profile and gear geometry, and a hybrid model for the compliance. The method includes tooth modifications such as tip relief, and uses the true geometry to find contacts. Thus, it also handles contact outside the nominal line of action, including tip contact. The study includes cases where a gear is subjected to both pitch error and profile slope error simultaneously. Numerical examples, relevant to the automotive industry, show the outcome of the simulations. It is shown how simulation-based tolerances for relevant industrial applications can be used to improve manufacturing outcome.

Idiopathic intracranial hypertension (IIH) is traditionally considered benign and characterized by symptoms related to increased intracranial pressure, including headache and impaired vision. We have previously demonstrated that brains of IIH patients exhibit patchy astrogliosis, increased perivascular expression of the water channel aquaporin-4 (AQP4) as well as degenerating pericyte processes and capillary basement membranes. Given the established association between pericyte degeneration and blood-brain barrier (BBB) dysfunction, we investigated blood protein leakage by light microscopic immunohistochemistry. We also assessed perivascular AQP4 expression by immunogold transmission electron microscopy. The study included 14 IIH patients and 14 reference (REF) subjects undergoing neurosurgery for epilepsy, aneurysm, or tumor. Evidence of BBB dysfunction, measured as area extravasated fibrinogen/fibrin, was significantly more pronounced in IIH than REF individuals. The extent of extravasated fibrinogen was positively correlated with increasing degree of astrogliosis and vascular AQP4 immunoreactivity, determined by light microscopy. Immunogold transmission electron microscopy revealed no overall changes in AQP4 expression at astrocytic vascular endfeet in IIH (n = 8) compared to REF (n = 11) individuals. Our results provide evidence of BBB leakage in IIH, signifying that IIH is a more serious neurodegenerative disease than previously considered.

Idiopathic normal pressure hydrocephalus (iNPH) is a neurodegenerative disease of unknown cause. We investigated the morphology of capillaries in frontal cortex biopsies from iNPH patients and related the observations to overnight intracranial pressure (ICP) scores. A biopsy (0.9×10 mm) was taken from where the ICP sensor subsequently was inserted. Brain capillaries were investigated by electron microscopy of biopsies from 27 iNPH patients and 10 reference subjects, i.e. patients (not healthy individuals) without cerebrospinal fluid circulation disturbances, in whom normal brain tissue was removed as part of necessary neurosurgical treatment. Degenerating and degenerated pericyte processes were identified in 23/27 (85%) iNPH and 6/10 (60%) of reference specimens. Extensive disintegration of pericyte processes were recognized in 11/27 (41%) iNPH and 1/10 (10%) reference specimens. There were no differences in basement membrane (BM) thickness or pericyte coverage between iNPH and reference subjects. The pulsatile or static ICP scores did neither correlate with the BM thickness nor with pericyte coverage. We found increased prevalence of degenerating pericytes in iNPH while the BM thickness and pericyte coverage did not differ from the reference individuals. Observations in iNPH may to some extent be age-related since the iNPH patients were significantly older than the reference individuals.

The object of this study was to investigate the different modal behavior of ultrafine aerosol particles collected at the Gruvebadet observatory located in Ny-Ålesund (Svalbard Islands, 78°55′N, 11°56′E). Aerosol particle size distribution was measured in the size range from 10 to 470 nm typically from the beginning of spring to the beginning of fall during four (non-consecutive) years (2010, 2011, 2013 and 2014). The median concentration for the whole period taken into account was 214 particles cm−3, oscillating between the median maximum in July with a concentration of 257 particles cm−3and a median minimum in April with 197 particles cm−3. The median total number concentration did not present a well-defined seasonal behavior, as shown by contrast looking at the sub/modal number concentration, where distinct trends appeared in the predominant accumulation concentration recorded during April/May and the preponderant concentration of Aitken particles during the summer months. Lastly, the short side-by-side spring 2013 campaign performed at the Zeppelin observatory with a differential mobility particle sizer was characterized by an aerosol concentration mean steady difference between the two instruments of around 14 %, thereby supporting the reliability of the device located at Gruvebadet.

This paper presents a share-driven scheduling protocol for networks with real-time properties. The protocol provides fairness and bandwidth isolation among predictable as well as unpredictable streams of messages on the network. The need for this kind of scheduled real-time communication network is high in applications that have requirements on flexibility, both during development for assigning communication bandwidth to different applications, and during run-time to facilitate dynamic addition and removal of system components.

A single exposure to intense impulse noise may cause diffuse brain injury, revealed by increased expression of immediate early gene products, transiently altered distribution of neurofilaments, accumulation of β-amyloid precursor protein, apoptosis, and gliosis. Neither hemorrage nor any gross structural damage are seen. The present study focused on whether impulse noise exposure increased the permeability of nerve and glial cell membranes to proteins. Also, we investigated whether a preceding, minor focal surgical brain lesion accentuated the leakage of cytosolic proteins. Anaesthetized rats were exposed to a single impulse noise at either 199 or 202 dB for 2 milliseconds. Transiently elevated levels of the cellular protein neuron specific enolase (NSE) and the glial cytoplasmic protein S-100 were recorded in the cerebrospinal fluid (CSF) during the first hours after the exposure to 202 dB. A surgical brain injury, induced the day before the exposure to the impulse noise, was associated with significantly increased concentrations of both markers in the CSF. It is concluded that intense impulse noise damages both nerve and glial cells, an effect aggravated by a preexisting surgical lesion. The impulse of the shock wave, i.e. the pressure integrated over time, is likely to be the injurious mechanism. The abnormal membrane permeability and the associated cytoskeletal changes may initiate events, which eventually result in a progressive diffuse brain injury.

In recent years, networking issues have become more and more important in the design of vehicle control systems. In the beginning of the 1990s a vehicle control system was built up by 'simple' computer nodes exchanging 'simple' and relatively non-critical data. Today we have moved into distributed vehicle control systems with functions spanning several nodes from different vendors. These systems are running on communication architectures consisting of different types of communication buses providing different functionality, from advanced control to entertainment. The challenge is cost efficient development of these systems, with respect to business, functionality, architecture, standards and quality for the automotive industry. In this article we present three different architectures - used in passenger cars, trucks, and construction equipments. Based on these case studies with different business and functionality demands, we will provide an analysis identifying commonalities, differences, and how the different demands are reflected in the network architectures.

Rotational acceleration of the head, as occurs in falls, car crashes, and sport injuries, may result in diffuse brain damage, with acute and chronic neurological and psychiatric symptoms. The present study addresses the effects of rotational trauma on the neuronal cytoskeleton, which stabilizes perikaryal, dendritic and axonal shape and function. The study focuses upon the distribution of (1) the phosphorylated form of the heavy neurofilament subunit, (2) the light neurofilament subunit, and (3) β-amyloid, a marker for brain injury. While normally restricted to axons, the phosphorylated heavy neurofilament subunits were drastically decreased in the axons after rotational trauma. Instead, they accumulated in the neuronal perikarya, normally devoid of the phosphorylated subunit. This alteration was seen, not only in the cerebral cortex, but also in the hippocampus, the cervical spinal cord, the cerebellum, the cranial nerves and the pyramidal tract. The distribution of the light subunit of neurofilaments was also altered post trauma. Only a weak β-amyloid immunoreactivity was detected in the brains of control animals. Promptly after the trauma, a large number of β-amyloid positive neurons appeared. Intensely co-localized immunoreactivity for the light subunit of neurofilaments and of β-amyloid was seen 3 days after the rotational trauma axons of in the subcortical white matter and in the granule cell layer of the dentate gyrus as well as in neurons of the hypoglossal nucleus. The reported alterations in the central nervous system neurons are similar to those in the human brain after closed head injury and in chronic degenerative diseases. Regions of importance for social behavior, memory and body movement were affected.

Exposure to impulse noise, above a certain intensity, is harmful to auditory function. Effects of impulse noise on the central nervous system (CNS) are largely unexplored, and there is little information on critical threshold values and time factors. We have recently shown that neurofilament proteins are affected in the cerebral cortex and the hippocampus. Now we show that impulse noise induces expression of the immediate early gene c-Jun products, proposed to play a role in the initiation of neuronal death, and apoptosis as revealed by TUNEL staining. Rat brains were investigated immunohistochemically 2 h to 21 days after exposure to impulse noise of 198 dB or 202 dB. c-Jun was expressed in neuronal perikarya in layers II-VI of the temporal cortex, the cingulate and the piriform cortices at 2 h to 21 days after both exposure levels. Granule neurons of the dentate gyrus and the CA1-3 in the hippocampus pyramidal neurons were similarly affected. The elevated expression of c-Jun products remained high at all postexposure times. TUNEL staining was positive among the same nerve cell populations 6 h after exposure and persisted even at 7 days at both exposure levels.

The hygroscopic growth of internally mixed ammonium sulfate and carboxylic acid particles was measured as a function of relative humidity by using a tandem differential mobility analyzer (TDMA). In TDMA experiments the organic compounds with different solubilities act in several ways, ranging from the behavior of totally insoluble substance to that of soluble compounds. The hygroscopic properties for mixtures containing either adipic acid or phthalic acid together with ammonium sulfate indicate that the organic fraction of the particles behaves as an inert mass and does not contribute to water uptake. The mixtures involving malonic acid or succinic acid increased the water uptake of the ammonium sulfate part only. The results indicate that the solubility of the organic fraction in individual aerosol particles clearly influences the aerosol–water interaction.

There is increasing evidence that impulse noise causes brain damage, but little is known about the mechanisms and extent of the response. Here, rat brains were investigated immunohistochemically for the expression of c-Fos, c-Myc, and β-APP during the first 3 weeks postexposure to impulse noise of 198 or 202 dB. The expression of c-Fos and c-Myc increased at 2 h after exposure in neurons of the cerebral cortex, thalamus, and hippocampus, and this c-Fos immunoreactivity remained elevated for the entire observation period. The c-Myc immunoreactivity peaked at 18 h in both neurons and astrocytes but returned to control levels at 7 days. Abnormal deposition of β-APP was evident within 6 h in the same brain regions. The β-APP immunoreactivity was most prominent at 18 h and remained increased over the 21-day period assessed. The observed effects were similar to those described in humans following traumatic brain injury and in Alzheimer's disease. We conclude that impulse noise influences the brain in a fashion similar to that in cases with progressive CNS degeneration.

Particle concentrations and size distributions have been measured from different heights inside and above a boreal forest during three BIOFOR campaigns (14 April–22 May 1998, 27 July–21 August 1998 and 20 March–24 April 1999) in Hyytiälä, Finland. Typically, the shape of the background distribution inside the forest exhibited 2 dominant modes: a fine or Aitken mode with a geometric number mean diameter of 44 nm and a mean concentration of 1160 cm−3and an accumulation mode with mean diameter of 154 nm and a mean concentration of 830 cm−3. A coarse mode was also present, extending up to sizes of 20 μm having a number concentration of 1.2 cm−3, volume mean diameter of 2.0 μm and a geometric standard deviation of 1.9. Aerosol humidity was lower than 50% during the measurements. Particle production was observed on many days, typically occurring in the late morning. Under these periods of new particle production, a nucleation mode was observed to form at diameter of the order of 3 nm and, on most occasions, this mode was observed to grow into Aitken mode sizes over the course of a day. Total concentrations ranged from 410–45 000 cm−3, the highest concentrations occurring on particle production days. A clear gradient was observed between particle concentrations encountered below the forest canopy and those above, with significantly lower concentrations occurring within the canopy. Above the canopy, a slight gradient was observed between 18 m and 67 m, with at maximum 5% higher concentration observed at 67 m during the strongest concentration increases.

The aim of this study is to monitor excitatory amino acids (EAAs) in the extracellular fluids of the brain and to characterize regional neuronal damage in a new experimental model for brain injury, in which rabbits were exposed to 180-260 krad/s2 rotational head acceleration. This loading causes extensive subarachnoid hemorrhage, focal tissue bleeding, reactive astrocytosis, and axonal damage. Animals were monitored for intracranial pressure (ICP) and for amino acids in the extracellular fluids. Immunohistochemistry was used to study expression of the gene c-Jun and apoptosis with the terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) technique. Extracellular glutamate, glycine, and taurine increased significantly in the hippocampus within a few hours and remained high after 24 h. Neuronal nuclei in the granule layers of the hippocampus and cerebellum were positive for c-Jun after 24 h. Little immunoreactivity was detected in the cerebral cortex. c-Jun-positive neuronal perikarya and processes were found in granule and pyramidal CA4 layers of the hippocampus and among the Purkinje cells of the cerebellum. Also some microglial cells stained positively for c-Jun. TUNEL reactivity was most intense at 10 days after trauma and was extensive in neurons of the cerebral cortex, hippocampus, and cerebellum. The initial response of the brain after rotational head injury involves brain edema after 24 h and an excitotoxic neuronal microenvironment in the first hour, which leads to extensive delayed neuronal cell death by apoptosis necrosis in the cerebral cortex, hippocampus and cerebellum.

Rapid head rotation is a major cause of brain damage in automobile crashes and falls. This report details a new model for rotational acceleration about the center of mass of the rabbit head. This allows the study of brain injury without translational acceleration of the head. Impact from a pneumatic cylinder was transferred to the skull surface to cause a half-sine peak acceleration of 2.1 × 105 rad/s2 and 0.96-ms pulse duration. Extensive subarachnoid hemorrhages and small focal bleedings were observed in the brain tissue. A pronounced reactive astrogliosis was found 8-14 days after trauma, both as networks around the focal hemorrhages and more diffusely in several brain regions. Astrocytosis was prominent in the gray matter of the cerebral cortex, layers II-V, and in the granule cell layer and around the axons of the pyramidal neurons in the hippocampus. The nuclei of cranial nerves, such as the hypoglossal and facial nerves, also showed intense astrocytosis. The new model allows study of brain injuries from head rotation in the absence of translational influences.

Particle concentrations and size distributions have been measured from different heights inside and above a boreal forest during three BIOFOR campaigns (14 April–22 May 1998, 27 July–21 August 1998 and 20 March–24 April 1999) in Hyytiälä, Finland. Typically, the shape of the background distribution inside the forest exhibited 2 dominant modes: a fine or Aitken mode with a geometric number mean diameter of 44 nm and a mean concentration of 1160 cm−3and an accumulation mode with mean diameter of 154 nm and a mean concentration of 830 cm−3. A coarse mode was also present, extending up to sizes of 20 μm having a number concentration of 1.2 cm−3, volume mean diameter of 2.0 μm and a geometric standard deviation of 1.9. Aerosol humidity was lower than 50% during the measurements. Particle production was observed on many days, typically occurring in the late morning. Under these periods of new particle production, a nucleation mode was observed to form at diameter of the order of 3 nm and, on most occasions, this mode was observed to grow into Aitken mode sizes over the course of a day. Total concentrations ranged from 410–45 000 cm−3, the highest concentrations occurring on particle production days. A clear gradient was observed between particle concentrations encountered below the forest canopy and those above, with significantly lower concentrations occurring within the canopy. Above the canopy, a slight gradient was observed between 18 m and 67 m, with at maximum 5% higher concentration observed at 67 m during the strongest concentration increases.

There is little information on threshold levels and critical time factors for blast exposures, although brain damage after a blast has been established both clinically and experimentally. Moreover, the cellular pathophysiology of the brain response is poorly characterized. This study employs a rat model for blast exposure to investigate effects on the neuronal cytoskeleton. Exposure in the range of 154 kPa/198 dB or 240 kPa/202 dB has previously been shown neither to cause visual damage to the brain, nor to affect the neuronal populations, as revealed with routine histology. Here, the brains were investigated immunohistochemically from 2 h to 21 days after blast exposure. A monoclonal antibody was used which detects only the phosphorylated epitope of the heavy subunit of the neurofilament proteins (p-NFH). This epitope is normally restricted to axons, that is, not demonstrable in the perikarya. Eighteen hours after exposure in the 240-kPa/202-dB range, p-NFH immunoreactivity accumulated in neuronal perikarya in layers II–IV of the temporal cortex and of the cingulate and the piriform cortices, the dentate gyrus and the CA1 region of the hippocampus. At the same time, the p-NFH immunoreactivity disappeared from the axons and dendrites of cerebral cortex neurons. The most pronounced immunostaining of neuronal perikarya was found in the hemisphere, which faced the blast source. The perikaryal accumulation of p-NFH was present also at 7 days but the neuronal perikarya had become negative at 21 days, at which time the axons again displayed p-NFH immunoreactivity. Exposure in the range of 154 kPa/198 dB caused similar, although less marked accumulation of p-NFH immunoreactivity in the neuronal perikarya. The findings are interpreted to show a dephosphorylation of NFHs in axons and dendrites and a piling up of p-NFHs in the perikarya due to disturbed axonal transport.

A numerical model has been used to simulate the conditions observed during the ACE‐2 Hillcloud experiment and to study the processes which may be taking place. The model incorporates gas phase chemistry of sulphur and nitrogen compounds upstream of the cloud, and the interaction of aerosol, precursor trace gases and oxidants within the cloud. Gas phase and aerosol inputs to the model have been provided from measurements made in the field. Dynamics of the air flow over the hill consisted of simple prescribed dynamics based on wind speed measurements, and also for some cases modelled dynamics. In this modelling study, it was found that during clean case studies particles down to 40–55 nm diameter were activated to form cloud droplets, the total number of droplets formed ranging from 200 to 400 drops/cm3. Significant modification of the aerosol spectra due to cloud processing was observed. In polluted cases particles down to 65–80 nm diameter were activated to form cloud droplets, the total number of droplets ranging from 800 to 2800 drops/cm3. Modification of the aerosol spectra due to cloud processing was slight. In all cases, changes in the aerosol spectra were due to both the uptake of HNO3, HCl, NH3and SO2from the gas phase, (the SO2being oxidised to sulphate) and the repartitioning of species such as HNO3, HCl, and NH3from larger particles onto smaller ones. Modelling results have been compared with observations made. Modelled droplet numbers are typically within 20% of the best measured values. The mode of the droplet distribution typically around 10–20 μm for clean cases and 4–8 μm for polluted cases was found to be in good agreement with the measured values of 10–25 μm for clean cases, but not in such good agreement for polluted cases. Measurements of upwind and interstitial aerosol distributions showed that the smallest particles activated were 30 and 50 nm for clean and polluted cases respectively, slightly smaller than the model values quoted above. Measured upwind and downwind aerosol spectra showed similar modification to that predicted by the model in eight out of the eleven model runs carried out. Chemistry measurements also give general evidence for both the uptake of species from the gas phase, and repartitioning of species from large particles onto smaller ones, though comparisons for individual cases are more difficult. From this modelling study, it can be concluded that in general, in the remote environment the exchange of hydrochloric acid, nitric acid and ammonia between aerosol particles and take up from the gas phase in the vicinity of cloud may be a very important mechanism in regulating the evolution of the aerosol spectrum. Further, the much more linear relationship between cloud droplet and accumulation mode aerosol number, which was observed in the measurements made during the ACE‐2 HILLCLOUD project is supported by these modelling results. The implications of this for the indirect effect will be explored in future work.

This article presents and evaluates the Slack Method, a new constructive heuristic for the allocation (mapping) of periodic hard real-time tasks to multiprocessor or distributed systems. The Slack Method is based on task deadlines, in contrast with other constructive heuristics, such as List Processing. The presented evaluation shows that the Slack Method is superior to list-processing-based approaches with regard to both finding more feasible solutions as well as finding solutions with better objective function values. In a comparative survey we evaluate the Slack Method against several alternative allocation techniques. This includes comparisons with optimal algorithms, non-guided search heuristics (e.g. Simulated Annealing), and other constructive heuristics. The main practical result of the comparison is that a combination of non-guided search and constructive approaches is shown to perform better than either of them alone, especially when using the Slack Method.

The hind leg of adult rats was exposed to vibrations (82 Hz; amplitude peak-to-peak 0.21 mm) for 4 hours during 5 consecutive days. Light and electron microscopic examination of the plantar and sciatic nerves were done immediately after the exposure period or after a 2- or 4-week recovery period. Light microscopic examination did not reveal any distinct signs of injury. However, ultrastructurally unmyelinated fibers in the plantar nerves showed distinct changes, with deranged axoplasmic structure and/or accumulation of smooth endoplasmatic reticulum. These changes were to a large extent reversible in 2 weeks and appeared normalized after a 4-week recovery period. No ultrastructural changes could be observed in the sciatic nerve. However, when the sciatic nerve was crushed after 5 days of vibration exposure, axonal outgrowth was increased 23% as compared with controls. These findings confirm that vibration induces nerve fiber damage, in this experimental model expressed as a “conditioning effect” contributing to increased regeneration potential of the corresponding neurones.

Right lymphatic duct was cannulated in 40 patients operated upon with cardiopulmonary bypass and moderate hypothermia, 30-32°C. The diagnoses were aortic valve disease in 20 cases and mitral valve disease in 20 cases. The operative procedure was valve replacement with a Bjork-Shiley prosthesis in 36 cases, fascia lata prosthesis in 1 case and plastic procedure in 3 cases. Coronary perfusion was used in 19 cases, ischaemic arrest in 10 cases and ischaemic arrest continued by coronary perfusion on the fibrillating heart in 11 cases. Frequent enzyme analyses were performed in lymph and serum for GOT, GPT, CPK and LDH before, during and after bypass. A statistically significant higher efflux of enzymes after bypass was found in the group of patients with ischaemic arrest continued by coronary perfusion as compared with coronary perfusion or ischaemic arrest. No difference was found between patients operated upon with coronary perfusion and those with ischaemic arrest. It is concluded that ischaemic arrest should not be followed by extended coronary perfusion on a fibrillating heart. Ischaemic arrest seems to have certain advantages over continuous coronary perfusion in selected cases.

We present a logic for stating properties such as, “after a request for service there is at least a 98% probability that the service will be carried out within 2 seconds”. The logic extends the temporal logic CTL by Emerson, Clarke and Sistla with time and probabilities. Formulas are interpreted over discrete time Markov chains. We give algorithms for checking that a given Markov chain satisfies a formula in the logic. The algorithms require a polynomial number of arithmetic operations, in size of both the formula and the Markov chain. A simple example is included to illustrate the algorithms.

Twenty-two adult patients suffering from common variable immunodeficiency (CVID) and sixteen patients with selective IgA deficiency were examined with regard to the mucocil-liary function of the nose. The surface structures of the nasal mucosa, e.g. cell distribution and degree of destruction and metaplasia, were judged from scanning electron microscopy of nasal biopsies. Bacteria were isolated from nasopharyngeal swabs. The results of the clinical and morphological investigations were analysed with regard to the duration of the disease and possible benefit of adequate prophylaxis with immunoglobulin. It was found that patients with CVID had a slower mucociliary transport rate and more extensive mucosal damages than patients with selective IgA deficiency. Most likely these alterations were due to repeated infections as patients who had had few infections or adequate immunoglobulin prophylaxis (CVID patients) had better mucociliary function and showed less extensive mucosal changes. Potentially pathogenic bacteria in the nasopharynx were found in equal numbers in both patient groups.

• The regulation of the fluid balance of the mucus is important for a good function of the mucociliary system in the nose. The nasal glands and the goblet cells have been proposed to be the main source of fluid. Microvilli-equipped epithelial cells, ciliated and nonciliated, constituting 70% to 90% of the cells on the turbinates in the nose, are of importance for the regulation of the hydration of the mucus. These cells have the same characteristics as other fluid-secreting cells elsewhere in the body. They have microvilli, a terminal web, folding of the basolateral membrane, and numerous cell organelles. Blockage of the energy supply strongly reduces the fluid secretion.(Arch Otolaryngol 1984;110:576-581)

Ten cylindrical implants, made of polycarbonate and covered with a 120-250-nm-thick layer of pure titanium, were implanted into each tibial metaphysis of five rabbits. Observation time was 12 weeks. The implants were surrounded by mature, living bone. No soft tissue intervened between bone and implant at any point. With TEM microscopy the titanium was shown to be bordered by a 20-nm-thick layer of proteoglycans, showing the characteristics of ground substance, and separating the collagen from the implant surface. Cells at the interface were likewise separated from the titanium by such a layer. Hydroxyapatite crystals were observed within the ground substance layer, occasionally seemingly in direct contact with the titanium. Normal mineralization was present 100-500 nm from the implant surface.While this study aims at defining interface anatomy, it also shows that macroscopi-cally smooth-surfaced titanium can readily heal into bone without a soft tissue envelope. This could be of help for materials' choice and design of permanently fixed implants.

BASEMENT is a distributed real-time architecture developed within the Swedish Road Transport Informatics Programme. BASEMENT is intended for vehicle internal use in the automotive industry. BASEMENT is holistic in that it covers application development as well as the hardwares and softwares that provide execution and communication support. The key constituents of BASEMENT are:•resource sharing (multiplexing) of processing and communication resources,•a guaranteed real-time service for safety critical applications,•a best-effort service for non-safety critical applications,•a communication infrastructure providing efficient communication between distributed devices, and•a software development method allowing resource independent and application oriented development of application software.

We present an overview of the research on real-time networking in the Hard-Real-Time Systems research group at the department of Computer Systems, Uppsala University. This includes a presentation of the general motivation and goals, as well as results and plans. On a more technical level, we present our method for providing timing guarantees in ATM-networks.

• The goal of this study was to investigate if the distribution of peptide growth factors in the human nasal mucosa could be correlated to its maintenance and to repair processes. Biopsy specimens from clinically healthy humans, aged 6 months to 70 years, were investigated immunohistochemically. In the intact human nasal mucosa, only scattered basal epithelial cells and rare, randomly distributed cells in the lamina propria expressed peptide growth factor immunoreactivity. In contrast, in areas with deficient epithelial lining and infiltration of inflammatory cells, intense insulinlike growth factor I immunoreactivity was demonstrable in reactive epithelial cells, while adjacent, more differentiated cells were nonreactive. Vascular wall cells, fibroblasts, macrophages, and exocrine gland cells in the reactive nasal mucosa showed variable insulinlike growth factor I immunoreactivity and, at lower frequencies and intensities, immunoreactivity to insulinlike growth factor II, basic fibroblast growth factor, platelet-derived growth factor, and transforming growth factor β, as did cells in the normally nonreactive exocrine glands. Macrophages and vascular smooth-muscle cells could in addition express platelet-derived growth factor immunoreactivity. Increased cell proliferation was recognized in reactive areas of the nasal mucosa specimens, ie, in those concomitantly showing distinct peptide growth factor immunoreactivity. We concluded that a complex pattern of peptide growth factor immunoreactivity is transiently expressed by reactive and regenerating nasal mucosal cells, contrasting with the nonreactive normal, differentiated cells. The close correlation between the appearance of peptide growth factors and the local repair and maintenance processes supports our working hypothesis that peptide growth factors are of functional importance for the nasal mucosa.(Arch Otolaryngol Head Neck Surg. 1991;117:1368-1377)

• Biopsy specimens of the nasal mucosa from the inferior turbinate of infants aged 2 to 26 months were examined by scanning electron microscopy. The specimens were obtained from 23 clinically healthy infants and compared with those from 43 infants with recurrent acute otitis media (RAOM). Potentially pathogenic bacteria were isolated from 61% of the control subjects and 90% of those with RAOM. Infants with RAOM had about as extensive alterations as the healthy ones. A single healthy child and one with RAOM had what was interpreted as a normal nasal mucosa; all others showed reduced frequencies of ciliated cells, deformation of cilia, extensive loss of normal mucosal epithelium, and metaplasia in their nasal epithelial lining. Severely damaged area could be seen close to more normal ones. Nasal mucosa in clinically healthy infants rarely had a normal appearance, probably due to frequent infections and the fairly long time needed for the repair process. We proposed that the high frequency of damaged, incompletely healed nasal mucosa may constitute an important factor with regard to the susceptibility to further infections.(Arch Otolaryngol Head Neck Surg 1989;115:571-580)

• Nasal polyps from 15 patients were all found to express increased insulinlike growth factor I immunoreactivity. A hypothesis for the formation of nasal polyps is described: macrophages, seen in allergic and infectious reactions, produce and release growth factors, tentatively including insulinlike growth factor I. In enclosed paranasal sinuses this results in an accumulation of insulinlike growth factor I stimulating the growth of both epithelium and blood vessels in the sinuses. The mucosa increasingly bulges out through the ostium after having filled out the sinusity. Continuing growth stimulation is supplied by the inflammatory reaction, endothelial cells in the polyp, and activated macrophages inside or outside the polyp.(Arch Otolaryngol Head Neck Surg 1988;114:1272-1275)

A commercially-available personal impactor was altered to sample viable microorganisms onto a semisolid, moist, gelatin medium rather than onto a stainless steel or filter surface. The Marple personal cascade impactor is an eight-stage sampler with predicted cut-offs of 20,15, 10,6,3.5,2,1, and 0.61 µm for stages one to eight, at a flow rate of 2 L/min. The possibility was examined that using trays containing a small amount of gelatin medium in place of the thin, flat filters of the original design would alter the impactor's performance. A polydisperse aerosol of di-2-ethylhexyl phthalate (DEHP or DOP) was sampled directly into an aerodynamic particle sizer and through a stage of the personal impactor. The aerosol particles penetrating the tested stage were sized and counted, and the counts compared with those in the total aerosol. With a Mylar® medium filter as the collecting substrate, the measured particle cut-offs (D50) for stages four to seven were 5.2,3.4,1.4, and 1.0 µm. With a tray containing gelatin as the collecting substrate, the D50 were 5.9,4.0,1.6, and 1.0 µm. The size separation of the personal sampler for ambient bacterial and fungal aerosols compared well with that of the Andersen microbiological impactor. The use of a moist collecting surface, compared to a dry surface, can be expected to enhance recovery of viable airborne microorganisms sensitive to dehydration.

Paracorporeal rat hearts were supplied with blood derived from the abdominal aorta of a supporting rat. The circulatory stability and working capacity of the supporting animal was analyzed in the experimental situation in terms of PO2, SO2, PCO2, HCO3, pH and electrolytes, all of which were within the normal range before and during a 60 min period of paracorporeal perfusion. For evaluation of ischemic damage in this model studies were made on three groups of excised hearts. They were subjected to 10, 15 or 20 min of complete global ischemia at 37°C (ambient temperature) and reperfused for 30 min, including ECG, observations of contractility and an analysis of creatine kinase efflux in the coronary effluent. The results showed good reproducibility and the data were in accordance with reports from similar studies on Langendorff preparations. The model, which is easily set up, inexpensive and based upon pulsatile blood perfusion, should be more physiologic than the conventional Langendorff preparation.

In the present study the expression of insulin-like growth factor I (IGF-I; somatomedin C) immunoreactivity was examined in endothelial cells during repair after injury to the intima in the femoral artery of adult rats. Two types of injury were examined: (1) endothelial denudation induced by the use of a catheter, and (2) vessel compression by short-term ligation. In untreated rats, arterial endothelial cells showed no or, only infrequently, low IGF-I immunoreactivity in their cytoplasm. Endothelial cells at the border to the denuded area showed increased IGF-I immunoreactivity one day after injury to the intima of the femoral artery. Thrombocytes and fibrin deposits as well as vital endothelial cells, covered by clots, were immunonegative. The maximal intensity of IGF-I immunoreactivity was reached within 3 days after insult. The IGF-I immunoreactivity in the endothelial cells remained elevated for at least 4 weeks, compared to the controls. Intimai thickenings appeared within a week after injury and many cells in these thickenings showed intense IGF-I immunoreactivity as did the covering endothelial cells. Smooth muscle cells in the media were generally immunonegative during control conditions and after endothelial denudation. Spontaneously hypertensive rats (SHR) showed, similarly to their matched controls (WKY), approximately the same patterns of IGF-I immunoreactivity in their endothelial cells both under normal conditions and after injury. It is concluded that IGF-I is likely to be involved in the repair of the intima in injured arteries.

The present study was aimed at assessing whether epidermal growth factor (EGF) and its receptors are present in the gastric mucosa during the healing of gastric ulcers. Immunohistochemical, immunochemical and functional studies were performed in rats after induction of ulcers in the oxyntic mucosa. Controls, which included non-operated and sham-operated animals, displayed only rare cells in the bottom of the oxyntic glands showing EGF-like immunoreactivity. Within one day after ulcer induction, a markedly increased number of chief cells in undamaged mucosa showed intense staining. Concomitantly, there was an increased immunoreactivity for EGF receptors in the mucous neck cells. Maximal immunostaining for both compounds was observed at 3 days after ulcer induction; augmented staining was still demonstrable after 3 weeks. RIA revealed significantly increased EGF concentration in the oxyntic mucosa three days after ulcer induction, and at this stage stimulated gastric acid secretion, measured in a parallel group of chronic fistula rats, indicated significant inhibition. The transient increases in EGF-like and EGF receptor immunoreactivities may stimulate gland cell proliferation. The local release of EGF-like substances may also serve to reduce gastric acidity and thereby promote ulcer healing.

Acute hypertension, experimentally induced by intravenous injection of metaraminol in adult rabbits, rapidly induced a damage of the blood-brain barrier in the cerebral cortex, as visualized by Evans-blue-conjugated albumin and horseradish peroxidase. Extravasation of these two exogenous tracers was demonstrated to occur in arterioles, in capillaries and, rarely, in venules. Peroxidase passed the endothelial cell into the nervous tissue in either of three different ways, i. e. through channels, often sigmoidshaped, in the cytoplasm, and transendothelial pinocytosis. The third pathway could, although rarely, be demonstrated between adjacent endothelial cells after cleavage of junctional complexes. The tracer peroxidase was further spread along the blood vessel within the basement membrane and in the extracellular space of the brain. Damaged endothelial cells with diffuse cytoplasmic peroxidase activity and large vesicles were occasionally observed within the areas with blood-brain barrier injury. There were also signs of increased pinocytotic activity in endothelial cells outside the barrier damaged cortical areas. Nerve cells and neuroglial cells could show either a diffuse cytoplasmic peroxidase activity or a vesicular location of the tracer, or sometimes both.

This paper presents BASEMENT™, a distributed real-time architecture developed for vehicle internal use in the automotive industry. The Basement concept is holistic, in the sense that it covers application development, as well as the hardware and software that provide execution and communication support. The key constituents of the concept are• resource sharing (multiplexing) of processing and communication resources• a guaranteed real-time service for safety critical applications• a best-effort service for non-safety critical applications• a communication infrastructure providing efficient communication between distributed devices• a program development methodology allowing resource independent and application oriented development of application software.

The present study was undertaken to evaluate possible beneficial effects of gammaglobulin treatment every 3 weeks during 6 months of 6-month to 2-year-old children. Every second of 44 children with recurrent acute otitis media (RAOM) received gammaglobulin, the other 22 served as controls. Nasal mucosal biopsy specimens were taken at 6-month intervals and analysed by light microscopy (LM) and scanning electron microscopy (SEM). Additional biopsies were obtained from another 15 children with RAOM and from 27 “healthy” children. No morphological differences in nasal mucosa could be demonstrated between the gammaglobulin treated and non-treated children. the structural changes observed in the first biopsy specimens usually persisted for at least 6 months, i.e. the study period, and were most prominent in the epithelium. Children with two or more episodes of acute otitis media (AOM) during the study period had more microabscesses compared to the children without any episode of AOM. Microabscesses were also more common in cases with secretory otitis media compared to cases with normal middle ear status. No morphological differences could be revealed related to the age of the children. Microabscesses, cell destruction and discontinuity of the epithelial lining were more common in children who harboured Branhamella calarrhalisin their nasopharynx. We conclude that intramuscular administration to children of gammaglobulin every 3 weeks during half a year neither improved their resistance to RAOM nor reduced the frequency or extent of structural changes in their nasal mucosa.

With the aim of estimating the unknown spread of HIV into the general society, a program for testing pooled routine sera from a clinical chemistry laboratory has been tried. Serum samples obtained from the daily inflow of blood tubes at the Clinical Chemistry Laboratory, Malmö General Hospital, and not labelled as risk samples for blood-borne infection(s), were collected and pools of up to ten sera each were constructed according to a special protocol. All serum pools were screened for anti-HIV and HBsAg. During the 32-months period of the study 3,016 serum pools from men and the same number from women were collected and analysed. These pools together contained sera from 26,468 male and 26,891 female patients, respectively. Altogether 33 male and 2 female pools were found anti-HIV positive. Anti-HIV-positive males appeared in all age groups, without significant difference between the groups. Two female pools from the age group 15 to 24 years were anti-HIV positive; these samples were drawn during the last year of testing. HBsAg was detected in 189 male and 129 female pools. From 1989 to the first half of 1991 the mean anti-HIV prevalence among the male samples investigated was 0.10%, with 95% confidence limits from 0 to 0.25%. If the upper confidence limit is exceeded in the future, this could be a warning of increased spread of HIV of in society.

Two approaches for time-resolved sampling of cerebrospinal fluid (CSF) in rats were compared regarding performance, reproducibility, and extent of the inevitable trauma caused by the implantation of a sampling tube. Several parameters were checked to evaluate the injury: blood cell contamination of CSF; concentrations in CSF of the cytosolic proteins neuron-specific enolase (NSE) and S-100 (chiefly present in astrocytes); blood-brain barrier leakage of a dye-protein complex; viability of nervous tissue cells as assessed by dye exclusion; light and electron microscopy. In one sampling method, a tube was forced epidurally into the cisterna magna via a hole in the calvarium, consistently damaging the meninges and the nervous tissue. When using the alternative sampling method, the tube was instead affixed to the posterior atlanto-occipital membrane and connected with the cisterna magna via a hole in the membrane. Such a procedure caused negligible damage. Both techniques induced an inflammatory response. We advocate the use of the second approach, i.e., to sample CSF via a hole in the atlanto-occipital membrane, as the method of choice due to its high reproducibility. It is fairly rapid, and associated with a negligible injury.Copyright © 1996 Elsevier Science Inc.

The nasal mucosa of 20 healthy subjects were examined before, during and after 6 weeks of regular use of xylometazoline nose-drops (1 mg/ml) 0.15 ml three times dayly. The subjects, except those affected by common colds, did not suffer any diminished mucociliar function during or after the trial. The surface structures were not found to have changed when examined with scanning electron microscopy. No morphological changes were observed in the intercellular space, basal membrane or tunica propria when using transmission electron microscopy. During the test period 5 of the subjects developed upper respiratory infections which temporarily prolonged the mucociliar transport time tested with small particles of saccharin. In some of these subjects a reduction in the number of ciliated cells was observed as well as an inflammatory reaction close to the epithelial cells. It is concluded that the use of xylometazoline over a 6-week period does not provoke any major functional or structural changes in a normal nasal mucosa.

Creatine phosphate is a precursor molecule for ATP synthesis, even under ischemic conditions. We investigated its functional and metabolic effects when added to cardioplegic solution. Rat hearts were subjected to normothermic ischemia for 15 or 30 min and then freeze-clamped. During ischemia there was gradual reduction of high-energy phosphates, but the hearts with creatine phosphate supplement showed higher myocardial content of ATP and of the creatine compound. Other hearts, subjected to 20 min of ischemia, were reperfused with blood for 40 min. Creatine phosphate supplementation resulted in better left ventricular isovolumic work during spontaneous activity, but in paced activity (400 beats/min) no significant differences were seen. After reperfusion, supplemented hearts showed a tendency to higher levels of ATP and creatine phosphate. In all three groups the hearts with cardioplegic supplement had significantly increased myocardial content of pyruvate without proportional lactate increase. The results indicate that creatine phosphate may be an effective constituent in cardioplegic solution.

Supplementation with phosphoenolpyruvate (PEP) and ATP was previously found to enhance the protective effect of potassium cardioplegia on rat hearts subjected to extensive ischemic trauma (30 min at 37°C) in the paracorporeal rat heart model. In the present experiments, the ischemia time was reduced to 20 min (37°C). Ventricular work after ischemia was best in control rats with potassium cardioplegia only. Supplementing the cardioplegic solution with PEP and ATP (group I) resulted in significantly reduced postischemic ventricular work and increased efflux of the creatine kinase isoenzyme MB (CK-MB). The same result was obtained when adenosine monophosphate (AMP) was added to the supplementation (group II). When guanosine monophosphate (GMP) was added instead of AMP (group III), the negative effects of PEP and ATP in the cardioplegic solution were partly abolished. Plain potassium cardioplegia, without additives, nevertheless gave the best results. There were no significant intergroup differences in the myocardial content of adenine nucleotides. The results contrasted with those in the previous study of more protracted ischemic trauma (30 min at 37°C) and possible explanations are discussed.

Right heart failure in patients with carcinoid heart disease is a serious prognostic sign. Consideration and adequate timing of valvular operations seem essential for the postoperative outcome. Without any relation to duration or progression of the metastasizing tumor disease, right heart failure developed and increased rapidly for a period of 12 to 17 months in four patients with classic carcinoid syndrome. Invasive hemodynamic and cardiac ultrasound investigations revealed severe carcinoid heart disease, and medical decompensation treatment gradually failed. Tricuspid and pulmonic valve replacement operations resulted in dramatic improvement in three of the patients, and these patients were still free of cardiac symptoms 10, 12, and 38 months postoperatively. One patient died 5 days postoperatively probably of septicemia. The preoperative and postoperative development of the cardiac disease is evaluated clinically, by cardiac ultrasound and plasma atrial natriuretic peptide concentrations, and related to the tumor disease. Surgical anatomy and operative technique are reported, and the beneficial value of prophylactic treatment of the effects of tumor-released vasoactive substances by a somatostatin analog is emphasized.

The visibility of the pericardium as well as of the space between the dorsal aspect of the sternal surface and the pericardial surface after cardiac surgery was determined by CT and/or MR with electrocardiographic (ECG)-gated spin-echo (SE) and gradient-echo sequences. Seventeen patients who had undergone cardiac operations and who were admitted for cardiac reoperation were investigated with CT and/or MR prior to sternal reentry. Five patients were investigated with CT alone, ten with both CT and MR, and two with MR only. At reoperation, retrosternal adhesions were classified as present or absent, and intrapericardial adhesions were classified as absent, minimal, moderate, or severe. A similar classification was applied to the CT and MR findings. In 14 of 15 patients, the CT findings were in agreement with those found at operation regarding postoperative retrosternal extrapericardial adhesions in the cranial retrosternal space and in 12 of 15 in the caudal retrosternal space. Computed tomography could not detect intrapericardial adhesions. Magnetic resonance was sensitive to metal artifacts from sternal sutures in both sequences and could therefore not be used to detect postoperative retrosternal extrapericardial adhesions. On the other hand, MR with ECG-gated SE sequences confirmed intrapericardial adhesions in 44 of 57 locations.

• Children with frequent recurrent respiratory tract infections and constant mucopurulent secretion from the nose were thoroughly examined, including bacteriologic and immunologic analyses. Biopsy specimens from the nasal mucosa were investigated by light and electron microscopy. Eight different histopathologic factors were distinguished and evaluated in relation to the continual nasal discharge. The mucus production was increased, due to an increased number of goblet cells or submucosal glands. The mucus transport was impaired owing to a decreased number of ciliated cells or different deficiencies in the structure of the cilia. The secretion of periciliary fluid was altered due to dysfunction of microvilliequipped cells and the availability of tissue fluid due to vascular changes. Leakage of tissue fluid partly reflects deficiencies in the epithelial lining. Purulent discharge was observed from microabscesses. Reactive changes in the nasal mucosa are described and discussed in relation to treatment schedules aimed at reducing short- and long-term discomfort and complications.(Arch Otolaryngol Head Neck Surg 1987;113:1294-1300)

In a randomized, double-blind study of patients undergoing elective coronary artery grafting, the effect of heparin-coated circuit combined with 50% reduction of systemic heparin bolus was investigated. Ten patients comprised group HC (heparin-coated) and ten group C (controls). The mean total doses of heparin were 172 IU/kg in group HC and 416 IU/kg in group C and the respective protamine doses were 0.96 and 3.96 mg/kg (both p<0.001). Activated clotting times during cardiopulmonary bypass were significantly shorter in group HC, and both intra- and postoperative bleeding was significantly less than in group C (7.7 vs. 11.7 ml/kg, p = 0.036, and 6.9 vs. 9.7 ml/kg, p = 0.004). Hemoglobin loss via the drains was 22.5 g in group HC and 43.7 g in group C (p<0.005). Hemolysis at the end of bypass was significantly greater in group C. Apart from one perioperative myocardial infarction in group HC the postoperative course was uneventful. Use of a heparin-coated circuit is concluded to permit complication-free reduction of heparin and protamine doses and to decrease both intra- and postoperative bleeding, which may favorably influence the outcome of coronary artery grafting.