Showing papers by "Linköping University published in 1984"
TL;DR: In this article, the optical properties of evaporated films of doped semiconducting In2O3 in the 2-6eV range were investigated, i.e., around the fundamental bandgap.
Abstract: In this paper we investigate the optical properties of evaporated films of doped semiconducting In2O3 in the 2-6-eV range, i.e., around the fundamental bandgap. The study serves two main purposes: to elucidate basic properties of a heavily n-doped semiconductor, and to improve our understanding of a technologically important material which is widely used when transmittance of visible or solar radiation needs to be combined with good electrical conduction or low thermal emittance.
552 citations
TL;DR: Stabilometric recordings of 25 soccer players did not confirm existing theories that an ankle joint injury itself produces a functional instability, and a significant improvement of stabilometric results and subjective "giving way" feelings were found after 6 weeks of coordination on an ankle disk.
Abstract: Stabilometry is an objective method for the quantitative study of postural equilibrium and has previously been shown to correlate to functional instability of the ankle joint. Stabilometric recordings of 25 soccer players did not confirm existing theories that an ankle joint injury itself produces a functional instability. Stabilometric re cordings of 38 soccer players with and without ankle taping did not show that taping influenced the stabilo metric values. In 10 soccer players with functional instability, a significant improvement of stabilometric results and subjective "giving way" feelings were found after 6 weeks of coordination on an ankle disk.
197 citations
TL;DR: The results indicate that extradural analgesia with a local anaesthetic drug can suppress the increases in the plasma concentrations of the catecholamines and cortisol after surgery, thus indicating that postoperative pain is a factor involved in the stress response following surgery.
Abstract: The influence of thoracic extradural local anaesthetics (0.5% bupivacaine) or extradural morphine on the metabolic response to upper abdominal surgery was compared with the administration of morphine i.v. in the period after operation. The extradural local anaesthetic group had significantly lower blood glucose and plasma FFA concentrations and consistently, but not significantly, lower blood glycerol and lactate concentrations than both the other groups. At 4 h both extradural groups had significantly lower plasma FFA and blood 3-hydroxybutyrate concentrations than the control group. Blood alanine concentration decreased in all three groups with a minimum at 24 h. There were no differences in serum insulin concentrations between the groups. It is concluded that thoracic extradural morphine differs from thoracic extradural local anaesthetics in being much less able to suppress the metabolic response associated with upper abdominal surgery.
173 citations
TL;DR: Most patients with ethmoid adenocarcinomas were collected, mainly during the last decade from a region with approximately 900,000 inhabitants and with a large amount of furniture industries, and computerized tomography especially furnishes important information.
Abstract: Adenocarcinoma makes up only a small percent of all nasal and paranasal sinus carcinomas, and is most often found in the ethmoid sinuses. Adenocarcinoma of the ethmoid sinuses is known to be associated with exposure to wood dust. Twenty-eight patients with ethmoid adenocarcinomas were collected, mainly during the last decade from a region with approximately 900,000 inhabitants and with a large amount of furniture industries. There were 4 women and 24 men in the study. Twenty of the men were exposed to dust from hardwood for 20 to 55 years (mean, 40 years) which is in accord with other reports and supports data on the increased risk for workers of developing adenocarcinoma of the ethmoid sinuses when exposed to dust from hardwood. Radiologic diagnosis is necessary to delineate the extent of these tumours, and computerized tomography (CT) especially furnishes important information. Most patients received preoperative radiotherapy followed by surgery, 50% of them survived 5 years, which is in accord with other reports.
140 citations
TL;DR: The findings suggest that the striking radiosensitivity of salivary gland serous epithelial cells is linked to their content of secretory granules, and it is conceivable that membranes which enclose organelles rich in metals with the ability to form redox systems show enhanced sensitity to radiation damage due to the metal-catalyzed induction of lipid peroxidation by ionizing radiation.
Abstract: The submandibular glands of male rats were exposed to 50 Gy X-irradiation as a single dose, with or without pre-treatment with either alpha-adrenergic agonists (noradrenaline, phenylephrine) or a cholinergic antagonist (atropine). The effects were analyzed by morphometric, cytochemical and biophysical methods. When X-irradiated without drug pre-treatment, many serous epithelial cells of the intralobular convoluted ducts displayed morphologic evidence of irreversible radiation damage, in contrast to neighbouring mucous and other cells which were unaffected. The effect was maximal 96 h after irradiation. Serous cells from animals irradiated after pre-treatment with atropine showed much more wide-spread injury than those of animals exposed to X-irradiation only. In contrast, serous cells suffered considerably less damage if their secretory granules had been depleted 1 or 2 h before irradiation with either noradrenaline or phenylephrine. Other epithelial cells showed no modulation of their slight radioresponsiveness by these drugs. The observations were substantiated by morphometry of three cell types: (a) mucous cells, (b) non-granulated serous and intralobular striated duct cells, and (c) granulated serous cells. The findings suggest that the striking radiosensitivity of salivary gland serous epithelial cells is linked to their content of secretory granules. These granules are rich in heavy metals, as demonstrated cytochemically with the sulphide silver method (SSM). Using particle-induced X-ray emission (PIXE) spectroscopy, the principal metals were shown to be Zn, Mn and Fe. It is conceivable that membranes which enclose organelles rich in metals with the ability to form redox systems (e.g. Fe2+ ai Fe3+) show enhanced sensitity to radiation damage due to the metal-catalyzed induction of lipid peroxidation by ionizing radiation. Disruption of secretory granules would be expected to release lytic enzymes into the cell sap, resulting in autolysis. This hypothesis is supported by the findings that atropine-which increases the number of granulated serous cells-enhances radiosensitivity, while noradrenaline and phenylephrine-which cause degranulation of serous cells-decrease radiosensitivity.
128 citations
TL;DR: It is shown that uncertainty can be derived from the fundamental constraints on the process of vision-the requirements for class-defining operations which are both shift-invariant and insensitive to changes in illumination.
Abstract: The uncertainty principle is recognized as one of the fundamental results in signal processing. Its role in inference is, however, less well known outside of quantum mechanics. It is the aim of this paper to provide a unified approach to the problem of uncertainty in image processing. It is shown that uncertainty can be derived from the fundamental constraints on the process of vision-the requirements for class-defining operations which are both shift-invariant and insensitive to changes in illumination. It is thus shown that uncertainty plays a key role in the language of vision, since it affects the choice of both the alphabet, the elementary signals, and the syntax, the inferential structure, of vision. The report is concluded with a number of practical illustrations of these ideas, taken from such image processing tasks as enhancement, data compression, and segmentation.
113 citations
TL;DR: A general technique is described for implementing sequential logic circuits optically and three interconnection methods are described and analyzed to describe their advantages and limitations.
Abstract: A general technique is described for implementing sequential logic circuits optically. In contrast with semiconductor integrated circuitry, optical logic systems allow very flexible interconnections between gates and between subsystems. Because of this, certain processing algorithms which do not map well onto semiconductor architectures can be implemented on the optical structure. The algorithms and processor architectures which can be implemented on the optical system depend on the interconnection technique. We describe three interconnection methods and analyze their advantages and limitations.
110 citations
TL;DR: In this paper, it was shown that porous materials such as paper can be impregnated with a conducting polymer by first soaking the paper in a solution of metal salt which acts as an initiator for subsequent polymerization.
Abstract: It is shown that porous materials such as paper can be impregnated with a conducting polymer by first soaking the paper in a solution of metal salt which acts as an initiator for subsequent polymerization. By using this procedure the conductivity of filter paper can be raised to as high as 2 (ohm cm)−1 for an FeCl3/H20/pyrrole combination. The role of the metal ion is discussea and it is pointed out that the impregnated papers exhibit both ionic and electronic conductivity. The polypyrrole paper composites exhibit some properties similar to carbon black-polymer composites.
99 citations
TL;DR: A questionnaire on climacteric symptoms was sent to every woman living in the city of Linköping, Sweden who was born in 1928 or 1930, and depression was positively correlated to the severity of the vasomotor symptoms.
97 citations
TL;DR: From the variation of the retention behaviour with substituent effects, as well as the mobile phase composition, some indications regarding the molecular interaction forces regulating the substrate-protein equilibria have been obtained.
97 citations
TL;DR: In this paper, the formation of the different microstructures is discussed in terms of surface energy minimization and thermally activated processes as surface and grain boundary migration, and the analysis of the microstructure shows that the growth of the film is markedly influenced by the substrate material.
01 Dec 1984
TL;DR: The result is that the joint covariance matrix of the transfer functions from input to output and from driving white noise source to the additive output disturbance, respectively, is proportional to the inverse of the joint spectrum matrix for the input and driving noise multiplied by the spectrum of the additiveoutput noise.
Abstract: Identification of black-box transfer function models is considered. It is assumed that the transfer function models possess a certain shift-property, which is satisfied for example by all polynomial-type models. Expressions for the variances of the transfer function estimates are derived, that are asymptotic both in the number of observed data and in the model orders. The result is that the joint covariance matrix of the transfer functions from input to output and from driving white noise source to the additive output disturbance, respectively, is proportional to the inverse of the joint spectrum matrix for the input and driving noise multiplied by the spectrum of the additive output noise. The factor of proportionality is the ratio of model order to number of data. This result is independent of the particular model structure used. The result is applied to evaluate the performance degradation due to variance for a number of typical model uses. Some consequences for input design are also drawn.
TL;DR: After treatment for 1 week with omeprazole, 40 mg daily, with or without an initial loading dose of 80 mg, intragastric acidity was decreased by more than 99%.
Abstract: Intragastric pH was measured during physiological conditions over 24-h periods in patients with peptic ulcer disease. After single oral doses of 20, 40, and 80 mg omeprazole we found a dose-dependent reduction in mean intragastric acidity ranging from 38% to 99%. After treatment for 1 week with omeprazole, 40 mg daily, with or without an initial loading dose of 80 mg, intragastric acidity was decreased by more than 99%. This is a more pronounced decrease in acidity than can be achieved even with very high doses of histamine H2-receptor antagonists.
TL;DR: In this article, a gas absorption/desorption unit and water-permeable tubing in front of the detector crystal were used for reproducible detection of certain hydrocarbons at a concentration level of parts per million.
TL;DR: A new type of convolver is presented which utilizes a kind of systolic array where the basic cell is mainly a full adder and the basic structure is a serial/parallel multiplier.
Abstract: A new type of convolver is presented. This type utilizes a kind of systolic array where the basic cell is mainly a full adder and the basic structure is a serial/parallel multiplier. A new formalism is developed which encompasses the whole family of serial/parallel multipliers. All these designs can be carried over to the design of convolvers since the convolution formula has the same structure on the word level as the multiplier on the bit level. Furthermore, the whole convolver can be embedded in one single uniform bit-serial one-dimensional structure. This extremely pin-saving and VLSI-oriented design can also be used for recursive filters and for 2D signal processing. Programmability (using a structure with varying precision and kernel size) can be traded for simplicity and efficacy. The paper contains comparative discussions of other convolvers; however, actual hardware performance is not given.
TL;DR: The results indicate that at midcervical levels most of the spinomesencephalic fibers ascend in the ventral funiculus, with only a moderate fraction ascending in the Ventral half of the lateralfuniculus.
Abstract: The projections to the midbrain from the spinal cord have been investigated in the cat with the degeneration technique and by using horseradish peroxidase (HRP) as an anterograde tracer. Two types of spinal cord lesions were performed: 1) Cordotomies at cervical or thoracic levels transecting the ventral and lateral funiculi. 2) Transections of the ventral, ventrolateral, dorsolateral or dorsal funiculus, respectively, at cervical levels. In the anterograde tracing experiments HRP was injected into the spinal cord at cervical, lumbar or sacral levels. The results show large projections to the lateral and ventrolateral parts of the periaqueductal gray (PAG1), the posterior pretectal nucleus (PP) and the nucleus of Darkschewitsch (D). More moderate projections go to the medial division of the periaqueductal gray (PAGm), the cuneiform nucleus (CF), the mesencephalic reticular formation (MRF), lateral part of the deep layer of the superio colliculus (SP) and magnocellular medial geniculate nucleus (GMmc), while scattered spinal fibers are present in the dorsal part of the periaqueductal gray (PAGd), the external inferior collicular nucleus (IX), the intermediate layer of the superior colliculus (SI), the lateral part of the red nucleus (NR) and in the Edinger-Westphal portion of the oculomotor nucleus (3). In addition a few fibers are present in the interstitial nucleus of Cajal (CA) and anterior pretectal nucleus (PAc). The results indicate that at midcervical levels most of the spinomesencephalic fibers ascend in the ventral funiculus, with only a moderate fraction ascending in the ventral half of the lateral funiculus. Almost no fibers ascend in the dorso-lateral funiculus and none appear to pass in the dorsal funiculus. No distinct somatotopic pattern was found in the spinomesencephalic projections, but more fibers from cervicobrachial segments terminate in the rostral than in the caudal parts of the terminal fields in PAG, CF, SP and IX, while the lumbar fibers were more numberous in the caudal parts. PP seems to receive spinal fibers mainly from the caudal half of the cord.
TL;DR: In this paper, the shoulder of the moisture content vs. square root of time curve is over-estimated by the one-dimensional solution of Fick's equation of moisture diffusion.
Abstract: Angle-ply laminates of graphite/epoxy Fiberite T300/1034, Ciba-Geigy T300/920 and Ciba-Geigy T300/914 were exposed to moist air of different relative humidities for 400 days. Laminates of T300/1034 reach a first plateau after about 100 days and a se cond plateau of saturation after about 400 days. The plateau levels are functions of the relative humidity and also of the residual stresses in the laminate. Compressive residual stresses retard the diffusion and lower the plateau levels. Laminates of T300/920 and T300/914 show more rapid moisture absorption than laminates of T300/1034 but no clearly detectable saturation plateau. The shoulder of the moisture content vs. square root of time curve is over-estimated by the one-dimensional solution of Fick's equation of moisture diffusion. A three-dimensional solution is given and is shown to predict the moisture absorption better for specimens of small width to thickness ratio.
TL;DR: The study indicates that residual curarization is a not uncommon fact which clinically is hard to assess and the only way to avoid residualCurarization seems to be to monitor the neuromuscular transmission during anaesthesia.
Abstract: Forty-eight patients subjected to elective surgery were randomly selected for evaluation of neuromuscular transmission in the postoperative period. All patients were anaesthetized with thiopentone, nitrous oxide, fentanyl and pancuronium. On arrival in the postoperative ward, alertness, ability to sustain head lift and the train-of-four (TOF) ratio were estimated. Twenty-five percent of the patients had a markedly impaired neuromuscular transmission which was not acceptable from a clinical standpoint. The given dose of pancuronium was not excessively high and a fairly long time had elapsed between reversal and TOF-ratio measurement. There was a poor correlation between TOF ratio and ability to sustain head lift. The study indicates that residual curarization is a not uncommon fact which clinically is hard to assess. The only wat to avoid residual curarization seems to be to monitor the neuromuscular transmission during anaesthesia.
TL;DR: The results show that the DCN project to several midbrain regions, and there appeared to be quantitative differences in the projections from various levels of the gracile nucleus, with more midbrain projecting fibers originating in the rostral than in the middle and caudal parts of the nucleus.
Abstract: The termination of the fibers from the dorsal column nuclei (DCN) to the midbrain has been investigated in the cat with the degeneration method, the anterograde horseradish peroxidase (HRP) method and autoradiography after 3H-leucine injections. The results show that the DCN project to several midbrain regions. The external nucleus of the inferior colliculus (IX) receives the heaviest projection from both the gracile and cuneate nuclei. The DCN fibers form three joint terminal zones in IX. Each terminal zone contains clusters with dense aggregations of DCN fibers. Fairly dense terminal networks are found in the posterior pretectal nucleus (PP) and the compact part of the anterior pretectal nucleus (PAc) as well. More scattered DCN fibers are present in the cuneiform nucleus (CF), the lateral part of the periaqueductal gray (PAG1), the red nucleus (NR), the nucleus of the brachium of the inferior colliculus (B), the mesencephalic reticular formation (MRF) and the intermediate and deep layers of the superior colliculus (SI, SP). The projections to all regions are mainly contralateral. Most of the few ipsilateral fibers terminate in IX. A somatotopic organization was seen in IX and NR. The gracile fibers terminate preferentially in the caudal and lateral part of IX and the cuneate ones preferentially in its rostral and medial part. In the red nucleus the gracile fibers terminate ventral to the cuneate ones. In the pretectal region there was a predominance for gracile fibers. There also appeared to be quantitative differences in the projections from various levels of the gracile nucleus, with more midbrain projecting fibers originating in the rostral than in the middle and caudal parts of the nucleus.
TL;DR: It is concluded that this substance should be given by continuous intravenous infusion in cases with severe methemoglobinemia, because this way of administration caused a steady decrease in the methemoglobin concentration compared to intermittent administration.
Abstract: A case of massive dapsone poisoning (15 g) in a 26 year old man is reported. The patient exhibited high plasma dapsone concentration, marked methemoglobinemia, and signs of hemolysis. He recovered completely after intensive treatment with methylene blue, activated charcoal, forced diuresis, and plasma exchange. In order to avoid overdosage of methylene blue it is concluded that this substance should be given by continuous intravenous infusion in cases with severe methemoglobinemia. This way of administration caused a steady decrease in the methemoglobin concentration compared to intermittent administration. Plasma exchange was of minor benefit, probably due to the large distribution volume of dapsone.
TL;DR: The BALB/c mouse developed mesangial deposits of immune constituents and light microscopical changes characteristic of immune complex glomerulonephritis after 8 weeks' treatment with mercuric chloride given by s.c. injection.
Abstract: The BALB/c mouse developed mesangial deposits of immune constituents and light microscopical changes characteristic of immune complex glomerulonephritis after 8 weeks' treatment with mercuric chloride given by s.c. injection. There were no signs of linear of granular immune deposits along the glomerular capillary basement membrane after 2 or 8 weeks. The antigen could not be identified. No antibodies to nuclear or renal structures were found. Using a histochemical method (silver amplification) mercury was detected by light and electron microscopy in tubular and glomerular structures. Mercury was present in secondary lysosomes of the mesangial cells after eight weeks of mercury poisoning.
TL;DR: D dosage (in mg) is more important than either volume or concentration when glucose‐free bupivacaine solutions are used for spinal analgesia.
Abstract: Spinal analgesia using 22.5 mg glucose-free bupivacaine, given either as 3.0 ml of 0.75% solution or 4.5 ml of 0.5% solution was studied in a double-blind fashion in 40 patients scheduled for transurethral surgery. No differences in onset, duration and regression of analgesia or motor blockade were noticed, indicating that dosage (in mg) is more important than either volume or concentration when glucose-free bupivacaine solutions are used for spinal analgesia. The cardiovascular effects were small and no side-effects attributable to the spinal anaesthetic were seen.
TL;DR: The results show that very small changes in the molecular structure of a drug can drastically alter not only its affinity for the albumin molecule but also the enantioselectivity in the reversible binding process.
TL;DR: In this article, the authors used secondary ion mass spectrometry (SIMS) to show that the surface segregation rate was sufficient over a wide range in Ts and In to Si flux ratios to cause the initial (2×1)−(100) Si surface reconstruction to transform to (3×4) due to the formation of an ordered In surface layer.
Abstract: The In incorporation probability σIn in (100) Si grown by molecular beam epitaxy was found, using secondary ion mass spectrometry (SIMS), to decrease from essentially unity at film growth temperatures Ts of ∼500 °C to <10−4 at 840 °C. SIMS depth profiles of both uniformly doped and modulation‐doped samples showed evidence of strong surface segregation with the amount of profile broadening directly related to σIn(Ts). A combination of in situ electron diffraction and Auger electron spectroscopy was used to show that the surface segregation rate was sufficient over a wide range in Ts and In to Si flux ratios to cause the initial (2×1)‐(100) Si surface reconstruction to transform to (3×4) due to the formation of an ordered In surface layer. The In surface coverage in the (3×4) state was ∼0.05–0.1 monolayer even though the bulk In concentration was ≤2×1017 cm3. The (2×1) to (3×4) surface phase transition was reversible by either terminating film growth and reevaporating the excess surface In or terminating th...
TL;DR: Visual suppression was more effective during a sinusoidal stimulation than during a pseudo-random stimulation at low frequencies, using the more precise rate sensor measurement technique.
Abstract: Thirteen normal subjects were investigated with a broad frequency-band (up to 4.5 Hz) rotatory test. The vestibular stimulation consisted of either a pseudo-random or a sinusoidal frequency sweep oscillation. Eye movements were recorded by EOG. Head movements were recorded either by a potentiometer attached to the chairs axis of rotation or by an angular rate sensor attached to a biteboard . Gain and phase values between eye and head movements were calculated. Measurements were performed in light and darkness during the execution of various fixation tasks. In the higher frequency range there was a in gain and phase between potentiometer and rate sensor measurements due to movement of the head relative to the headholder . Visual suppression, in agreement with earlier studies, was more effective during a sinusoidal stimulation than during a pseudo-random stimulation at low frequencies, using the more precise rate sensor measurement technique. Different instructions in the dark could alter the gain values at lower frequencies (up to 2 Hz) during sinusoidal stimulation. During pseudo-random stimulation no such differences could be elicited. Under all test conditions with the rate sensor, the gain values approached unity at about 3 Hz.
TL;DR: In this article, a Pd-MOS structure has been developed which has proven to be sensitive to hydrogen both in air at atmospheric pressures and in UHV. The ability to work over a wide pressure range makes it an inte...
TL;DR: In this article, the authors report results of photo-emission experiments and a new bulk band-structure calculation for monotungsten carbide (WC) with the use of synchrotron radiation.
Abstract: We report results of photoemission experiments and a new bulk band-structure calculation for monotungsten carbide (WC). Three types of photoemission experiment were performed on a WC(0001) surface, with the use of synchrotron radiation. Normal-emission angle-resolved spectra in the range $10\ensuremath{\le}h\ensuremath{
u}\ensuremath{\le}30$ eV cannot be interpreted assuming dominance of direct transitions, rather a one-dimensional density-of-states (1D DOS) sampling of initial states is required. By exploiting the natural polarization of the synchrotron-radiation source, initial-state symmetries of three features are unambiguously assigned, ${\ensuremath{\Lambda}}_{1}$ at -9.4 and -1.0 eV and ${\ensuremath{\Lambda}}_{3}$ at -3.0 eV, and these same features are associated with appropriate-symmetry high-DOS regions along $\ensuremath{\Delta}(\ensuremath{\Gamma}\ensuremath{-}A)$ in the bulk band structure. Two features displaying no clear-cut polarization dependence cannot be associated with high-DOS regions along $\ensuremath{\Delta}$ and are attributed to emission scattered from elsewhere in the Brillouin zone. The strong amplitude dependence with emission angle of a sharp peak near ${E}_{F}$ is attributed to symmetry selection rules related to a mirror-plane collection geometry excited by polarized radiation. Data from a second experiment using a cylindrical mirror analyzer (CMA), $10\ensuremath{\le}h\ensuremath{
u}\ensuremath{\le}30$ eV, are also interpreted with the use of the bulk band structure, but with more limited success. Here, however, clear evidence of direct transitions is seen. A total DOS is probed in the third experiment, which again uses a CMA, with $65\ensuremath{\le}h\ensuremath{
u}\ensuremath{\le}200$ eV. The main valence band extends 8 eV below ${E}_{F}$ while C $2s$ electrons form a separate band, 3-eV FWHM centered at -12.5 eV. Utilizing the W $5d$ Cooper minimum at $160 \mathrm{eV}=h\ensuremath{
u}$, we assign the upper half of the main valence band to predominately W $5d$---derived states, while in the lower half, C $2p$---derived states dominate.
TL;DR: In this article, the robustness of nonlinear regulators for nonlinear systems with respect to variations in gain is investigated and it is shown that there exist regulators that produce asymptotically stable closed-loop systems, but do not tolerate any variation in gain without instability.
Abstract: The robustness of nonlinear regulators for nonlinear systems with respect to variations in gain is investigated. It is shown that there exist regulators that produce asymptotically stable closed-loop systems, but do not tolerate any variation in gain without instability. However, if the linearized closed-loop system is also asymptotically stable, then there is always some gain margin. For a wide class of optimal regulators, it is shown that the gain margin is infinite with respect to increases in gain and that decreases down to 0.5 can be tolerated. The robustness properties of linear quadratic control laws are thus generalized.
TL;DR: Chiral capillary gas chromatography now permits a determination of the enantiomeric composition of a few nanograms of a compound present in a mixture of many others, and will additionally permit structural elucidation in pheromone research and related areas.