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Showing papers by "University of Copenhagen published in 1990"


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26 Apr 1990
TL;DR: In this article, a strategy for redesigning jobs to reduce unnecessary stress and improve productivity and job satisfaction is proposed, which is based on the concept of job redesigning and re-designing.
Abstract: Suggests a strategy for redesigning jobs to reduce unnecessary stress and improve productivity and job satisfaction.

8,329 citations


Journal ArticleDOI
TL;DR: A unified theory of visual recognition and attentional selection is developed by integrating the biased-choice model for single-stimulus recognition with a choice model for selection from multielement displays in a race model framework.
Abstract: A unified theory of visual recognition and attentional selection is developed by integrating the biased-choice model for single-stimulus recognition (Luce, 1963; Shepard, 1957) with a choice model for selection from multielement displays (Bundesen, Pedersen, & Larsen, 1984) in a race model framework. Mathematically, the theory is tractable, and it specifies the computations necessary for selection. The theory is applied to extant findings from a broad range of experimental paradigms. The findings include effects of object integrality in selective report, number and spatial position of targets in divided-attention paradigms, selection criterion and number of distracters in focused-attention paradigms, delay of selection cue in partial report, and consistent practice in search. On the whole, the quantitative fits are encouraging.

1,586 citations


Journal ArticleDOI
TL;DR: The results seem to suggest that strength training can counteract the age-related changes in function and morphology of the ageing human skeletal muscle.
Abstract: The function and morphology of knee extension/m. vastus lateralis and elbow flexion/m. biceps brachii were studied in young (28 +/- 0.1 years, n = 7) and elderly (68 +/- 0.5 years, n = 8) sedentary subjects and in elderly swimmers (69 +/- 1.9 years, n = 6), runners (70 +/- 0.7 years, n = 5) and strength-trained subjects (68 +/- 0.8 years, n = 7). On average, the training groups had, for the 12-17 years before the measurements were taken, performed their training regimen 3 +/- 0.1 times a week. Compared with the young subjects, the maximal isometric torque of the sedentary elderly subjects was 44% (P less than 0.05) lower in knee extension and 32% (P less than 0.05) lower in elbow flexion, and speed of movement was between 20 and 26% (P less than 0.05) lower in both knee extension and elbow flexion. The cross-sectional area of m. quadriceps femoris and the elbow flexors was also 24% (P less than 0.05) and 20% lower respectively, and the specific tension was 27% (P less than 0.05) lower in m. quadriceps femoris and 14% (P less than 0.05) lower in the elbow flexors. A 27% (P less than 0.05) higher content of myosin heavy chain type I and a 39% (P less than 0.05) higher content of the slow-type myosin light chain--2 was observed in m. vastus lateralis of the sedentary elderly subjects as compared with the young subjects. The same tendency was also seen with m. biceps brachii. Since the histochemical fibre-type distribution was identical and no major co-expression of type I and type II myosin heavy-chain isoforms was observed with immunocytochemistry, the increase in slow myosin isoforms with ageing seems mainly related to a larger relative area of type I fibres, induced by a selective atrophy of type II fibre area. An increased content of the beta-isoform of tropomyosin was also demonstrated with ageing. In contrast to the swimmers and runners, the elderly strength-trained subjects had maximal isometric torques, speed of movements, cross-sectional areas, specific tensions and a content of myosin and tropomyosin isoforms in both muscles studied identical to those of the young controls. These results seem to suggest that strength training can counteract the age-related changes in function and morphology of the ageing human skeletal muscle.

589 citations


Journal ArticleDOI
TL;DR: A simple model for migraine attacks is suggested: A pathological disturbance in one cerebral hemisphere causes the aura symptoms and after a time delay, it also causes the headache by stimulating local vascular nociceptors.
Abstract: Ten years of study has resulted in considerable but fragmented knowledge about regional cerebral blood flow in migraine with aura (classic migraine). In the present study, the number of repeatedly studied patients (n = 63) was large enough to determine statistically significant sequences of events and statistically significant spatial relations. The first observable event was a decrease of regional cerebral blood flow posteriorly in one cerebral hemisphere. Further development of this pathological process was accompanied by the aura symptoms. Thereafter headache occurred while regional cerebral blood flow remained decreased. During the headache phase, regional cerebral blood flow gradually changed from abnormally low to abnormally high without apparent change in headache. In some patients headache disappeared while regional cerebral blood flow remained increased. Although regional cerebral blood flow reduction and aura symptoms in the great majority of patients were unilateral, one-third had bilateral headache. Unilateral headache usually localized to the side on which regional cerebral blood flow was reduced and from which the aura symptoms originated (i.e., aura symptoms were perceived to occur contralaterally but presumably originated in the hypoperfused hemisphere). Our results suggest a simple model for migraine attacks: A pathological disturbance in one cerebral hemisphere causes the aura symptoms and after a time delay, it also causes the headache by stimulating local vascular nociceptors. Bilateral headache caused by a unilateral cerebral disturbance may be explained by recent neuroanatomical and neurophysiological findings.

552 citations


Journal ArticleDOI
TL;DR: It was shown that the additional number of motoneurones recruited in a monosynaptic test reflex by a constant excitatory conditioning stimulus was very much dependent on the size of the test reflex itself.
Abstract: In parallel experiments on humans and in the cat it was investigated how the sensitivity of monosynaptic test reflexes to facilitation and inhibition varies as a function of the size of the control test reflex itself. In man the monosynaptic reflex (the Hoffmann reflex) was evoked in either the soleus muscle (by stimulation of the tibial nerve) or the quadriceps muscle (by stimulation of the femoral nerve). In the decerebrate cat monosynaptic reflexes were recorded from the nerves to soleus and medial gastrocnemius muscles; they were evoked by stimulation of the proximal ends of the sectioned L7 and S1 dorsal roots. Various excitatory and inhibitory spinal reflex pathways were used for conditioning the test reflexes (e.g. monosynaptic Ia excitation, disynaptic reciprocal inhibition, cutaneous inhibition, recurrent inhibition, presynaptic inhibition of the Ia fibres mediating the test reflex). It was shown that the additional number of motoneurones recruited in a monosynaptic test reflex by a constant excitatory conditioning stimulus was very much dependent on the size of the test reflex itself. This dependency had the same characteristic pattern whatever the conditioning stimulus. With increasing size of the test reflex the number of additionally recruited motoneurones first increased, then reached a peak (or plateau) and finally decreased. A similar relation was also seen with inhibitory conditioning stimuli. The basic physiological factors responsible for these findings are discussed. Finally, the implications for the interpretation of experiments in man with the H-reflex technique are considered.

493 citations


Journal ArticleDOI
TL;DR: The improved possibility of quantitating the defect of the BBB by MRI may give new information about pathogenesis or etiology, and leads to improved methods in monitoring the efficacy of treatments in intracranial diseases.
Abstract: In this study quantitation of the degree of deficiency of the blood-brain barrier (BBB) in patients with multiple sclerosis or brain tumors, by using MRI, is shown to be possible As a measure of permeability of the BBB to Gadolinium-DTPA (Gd-DTPA) the flux per unit of distribution volume per unit of brain mass was used This quantity was found by introducing the longitudinal relaxation rate (R1) as a measure of concentration of Gd-DTPA in the brain tissue in the mathematical model for the transcapillary transport over the BBB High accordance between the observed data points and the model was found, and the results were comparable to results obtained from similar studies using positron emission tomography The improved possibility of quantitating the defect of the BBB by MRI may give new information about pathogenesis or etiology, and leads to improved methods in monitoring the efficacy of treatments in intracranial diseases © 1990 Academic Press, Inc

441 citations


Journal ArticleDOI
TL;DR: Etude de la regulation hormonale des enzymes appartenant a la famille de serine protease inhibiteur (plasminogen activator et urokinase)

404 citations


Journal ArticleDOI
TL;DR: The present study indicates, that the size of the apical foramen and possibly the avoidance of bacterial contamination during the surgical procedure are explanatory factors for pulpal healing.
Abstract: The purpose of the present investigation was to determine the long-term prognosis of autotransplanted premolars with respect to tooth survival and pulpal healing. The material consisted of 195 patients aged 7 to 35 years, with a total of 370 autotransplanted premolars with observation period ranged from 1 to 13 years. Teeth transplanted with incomplete and complete root formation showed 95 per cent and 98 per cent long-term survival respectively: Pulp healing as evaluated by sensibility testing and radiographic signs of partial pulp canal obliteration was usually verified 6 months after transplantation. The frequency of pulpal healing (versus pulp necrosis), appeared to be closely related to stage of root development at time of transplantation. Teeth transplanted with incomplete and complete root formation showed 96 per cent and 15 per cent pulp healing respectively. Another and associated factor which could equally well predict pulpal healing was the diameter of the apical foramen of the graft. Finally, in teeth with completed root formation, the use of bursa with internal cooling and no extra-alveolar storage prior to transplantation seemed to increase the chance for pulpal healing. The present study indicates, that the size of the apical foramen and possibly the avoidance of bacterial contamination during the surgical procedure are explanatory factors for pulpal healing.

387 citations


Journal ArticleDOI
TL;DR: The degradation of the uPA‐PAI‐1 complex is preceded by internalization and is inhibited by chloroquine, an inhibitor of lysosomal protein degradation, suggesting the existence of a cellular cycle of uPA.
Abstract: The receptor for urokinase plasminogen activator (uPA) has been previously shown not to internalize its ligand, but rather to focalize its activity at the cell surface, allowing a regulated cell surface plasmin dependent proteolysis. The receptor in fact binds the proenzyme pro-uPA and allows its very efficient conversion to the active two chains form. Receptor bound active uPA can also interact with its specific type 1 inhibiror (PAI-1) which is therefore able to inhibit the cell surface plasmin formation. In this paper we show that the uPA-PAI-1 complex bound to the uPA receptor is internalized and degraded. U937 cells were incubated at 4 degrees C with labeled uPA-PAI-1 (and other ligands), the temperature then raised to 37 degrees C and the fate of the ligand followed for 3 h thereafter. The uPA-PAI-1 complex was internalized into the cells (i.e. could not be dissociated by acid treatment) and thereafter degraded (i.e. appeared in the supernatant in a non TCA-precipitable form). Other ligands (free uPA, ATF and DFP-treated uPA) were not internalized nor degraded. The degradation of the uPA-PAI-1 complex is preceded by internalization and is inhibited by chloroquine, an inhibitor of lysosomal protein degradation. These data suggest the existence of a cellular cycle of uPA. After synthesis pro-uPA is secreted, bound to the receptor and activated to two chain uPA. On the surface, uPA can activate surface bound plasminogen to produce surface bound plasmin. In the presence of PAI-1 uPA activity is inhibited and plasmin production interrupted, while the uPA-PAI-1 complex is internalized and degraded.

383 citations


Journal ArticleDOI
TL;DR: Serum lipids and lipoproteins are significantly altered as a consequence of the menopause, resulting in a more atherogenic lipid profile which may partly explain the increased risk of cardiovascular disease observed in post-menopausal women.

317 citations


Journal ArticleDOI
TL;DR: An account is given of 114 new or otherwise interesting species of benthic marine flagellates from Fiji, Northern Australia (Queensland), Hawaii, Panama and Brazil.
Abstract: An account is given of 114 new or otherwise interesting species of benthic marine flagellates from Fiji, Northern Australia (Queensland), Hawaii, Panama and Brazil. Most species are heterotrophs drawn from the euglendis, dinoflagellates, kinetoplastids, bicosoecids, heteroloboseids, and a variety of taxa of uncertain affinities. The work emphasizes the rich variety of protist taxa in marine benthic sites. New names are Amphidinium corrugatum, Anisonema glaciale, Bodo cephalophorus, B. platyrhynchus, B. saliens, Bordnamonas tropicana, Cafeteria ligulifera, C. marsupialis, C. minuta (Ruinen, 1938) nov. comb., Cryptaulax elegans, Dinematomonas inaequalis = Dinema inaequale, Dinematomonas maculata (= Dinema maculatum), Dinematononas valida (= Dinema validum), Diplonema ambulator, Diplonema metabolicum, Discocelis punctata, Dolium sedentarium, Goniomonas amphinema, Goniomonas pacifica, Gyrodinium oblongum, Heteronema exaratum, H. splendens, H. vittatum, Mastigamoeba psammobis, M. skujae nom. nov., Massisteria ...

Journal ArticleDOI
TL;DR: The observations suggest that zinc many play a role in the selective death of dentate hilar neurons after cerebral ischemia, a sign of cellular degeneration.

Journal ArticleDOI
TL;DR: A prolonged reaction time suggested a partial deafferentation of the reflex stabilization of the ankle and substantiated the theory of a proprioceptive deficit being responsible for ankle instability.
Abstract: The reaction of 15 functionally unstable ankles to sudden inversion was described by monitoring muscle activity, joint motion, and alternation of the body center of pressure. The results were compared with those of 15 stable controls. Stable and unstable subjects showed a similar reaction pattern to sudden inversion: first, a peripheral reflex action, namely, a contraction of the peronei counteracting the ankle inverting momentum, and, then, a centrally elicited pattern, namely, a flexion of the hip, knee, and ankle relieving the vertical pressure on the ankle and producing ankle eversion. Unstable subjects did not show a defect in their central processing of afferent input. In contrast, a prolonged reaction time (median 84 msec compared with 69 msec in stable subjects) suggested a partial deafferentation of the reflex stabilization of the ankle and substantiated the theory of a proprioceptive deficit being responsible for ankle instability.

Journal ArticleDOI
TL;DR: In this paper, the authors present a coherent summary of the current understanding of chemisorption phenomena, stressing theoretical concepts and developments rather than experimental techniques, in a search for physical concepts that can systematise the observational data and perhaps make it possible to predict the behaviour of systems that have not yet been studied.
Abstract: Presents a coherent summary of the current understanding of chemisorption phenomena, stressing theoretical concepts and developments rather than experimental techniques. The rapid experimental development of surface science requires a more systematic approach to the explosion of chemisorption data. To this end, the common characteristics of chemisorption systems are first reviewed before the differences are discussed and trends identified, in a search for physical concepts that can systematise the observational data and perhaps make it possible to predict the behaviour of systems that have not yet been studied. The major topics discussed are the adiabatic potential energy surface, the electronic structure problem, the Newns-Anderson model, atomic and molecular chemisorption, and reactions and heterogeneous catalysis. A comprehensive review of experimental results is not attempted within the concept-oriented approach of this study. It is shown that simple models are able to describe semi-quantitatively the chemisorption bond for simple gas atoms, and that there is some understanding of the surface and adsorbate parameters that determine important experimental observables such as the chemisorption energy, bond lengths, and vibrational frequencies. For molecular chemisorption and the dissociation of molecules on metal surfaces the understanding is less well developed, but there is some qualitative understanding of a number of trends.

Journal ArticleDOI
TL;DR: There was a tendency for cardiac output to increase in the heat, which may have contributed to the increase in skin circulation, together with a possible further reduction in flow to other vascular beds, because muscle blood flow was not reduced.
Abstract: The effect of heat stress on blood flow and metabolism in an exercising leg was studied in seven subjects walking uphill (12-17%) at 5 km/h on a treadmill for 90 min or until exhaustion. The first 30 min of exercise were performed in a cool environment (18-21 degrees C); then subjects moved to an adjacent room at 40 degrees C and continued to exercise at the same speed and inclination for a further 60 min or to exhaustion, whichever occurred first. The rate of O2 consumption, 2.6 l/min (1.8-3.3) (average from cool and hot conditions), corresponded to 55-77% of their individual maximums. In the cool environment a steady state was reached at 30 min. When the subjects were shifted to the hot room, the core temperature and heart rate started to rise and reached values greater than 39 degrees C and near-maximal values, respectively, at the termination of the exercise. The leg blood flow (thermodilution method), femoral arteriovenous O2 difference, and consequently leg O2 consumption were unchanged in the hot compared with the cool condition. There was no increase in release of lactate and no reduction in glucose and free net fatty acid uptake in the exercising leg in the heat. Furthermore, the rate of glycogen utilization in the gastrocnemius muscle was not elevated in the hot environment. There was a tendency for cardiac output to increase in the heat (mean 15.2 to 18.4 l/min), which may have contributed to the increase in skin circulation, together with a possible further reduction in flow to other vascular beds, because muscle blood flow was not reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Journal ArticleDOI
TL;DR: The present study demonstrates that treatment with female sex hormones in this particular combination is a realistic approach to the treatment of women with established postmenopausal osteoporosis.
Abstract: Forty women aged 64.7 ± 5.1 yr with established postmenopausal osteoporosis were blindly allocated to 1 yr's treatment with either continuous combined estrogen/progestogen therapy (2 mg estradiol + 1 mg norethisterone acetate + 500 mg calcium daily) or placebo + 500 mg calcium daily. In the group treated with hormones bone mineral density in the spine (dual photon absorptiometry) and bone mineral content in the ultradistal forearm (single photon absorptiometry) increased highly significantly by 8–10% during the 1 yr of treatment. Bone mineral content in the mid-shaft of the forearm (single photon absorptiometry) and the total body bone mineral (dual photon absorptiometry) increased by 3–5% when compared to that in the placebo group, which showed virtually unchanged values at all measurement sites. Seven of the women treated with hormones were examined after a further year of treatment. BMC increased by another 3–6%, reaching a 12% increase in bone mineral density in the spine after 2 yr of treatment. Bioc...

Journal ArticleDOI
01 Feb 1990-Nature
TL;DR: In this article, the authors report on studies of melt layers in two Canadian high-Arctic surface-to-bedrock ice cores and interpret their varying concentrations in terms of changing summer temperatures over the past 10,000 years.
Abstract: MELT layers in ice cores are formed by melting on the snow-pack surface, which produces water that percolates down and refreezes in the colder snow layers below. Melt layers are distinguished by their 'bubble' texture. Because more ice forms in the snow pack in warm summers than in cool summers, the changing concentration with depth of melt layers in snow pits1,2 and ice cores3–5 is an indicator of past summer climate. Here we report on studies of melt layers in two Canadian high-Arctic surface-to-bedrock ice cores. Although changes in elevation of the drill site owing to isostatic depression and uplift may contribute up to 40% of the total climatic signal recorded in the melt layers, we interpret their varying concentrations in terms of changing summer temperatures over the past 10,000 years. The warmest summers occurred 8–10 kyr ago and the coldest only 150 years ago. The summers over the past 100 years have been the warmest for more than 1,000 years, but are still not as warm as those of the early Holocene. The melt-layer record is in broad agreement with geological records of glacier retreat during the Holocene6–8, indicating that these data also contain information of regional significance.

Journal ArticleDOI
TL;DR: In an acid sandy loam soil (pH 3.8), field production of N2O was two orders of magnitude higher at thaw in the spring than at any time during the rest of the year.
Abstract: SUMMARY In an acid sandy loam soil (pH 3.8), field production of N2O was two orders of magnitude higher at thaw in the spring than at any time during the rest of the year. Soil thaw in midwinter did not result in any increase in N2O flux. Soil water content remained at, or above field capacity during measurements; nitrate was added in excess. This effect could be reproduced in the laboratory: thawing soil cores at controlled temperature, nitrate and moisture yielded a large flush of N2O compared to an unfrozen control. The results indicate the importance of microbial N2O production during thaw for total annual N2O-emission.

Journal ArticleDOI
TL;DR: In this article, the growth kinetics of vaterite (CaCO3) from aqueous solution between about 10 and 45°C and at ionic strengths from 15mM to 315mM were determined by recording pH as a function of time and analysing these data by a BASIC computer program, correcting for complexes and using activity coefficients.

Journal ArticleDOI
TL;DR: The possibility that naturally occurring antibodies may function as specific physiological carriers and regulators of cytokines is discussed, based mainly on evidence obtained by investigating autoantibodies to interleukin 1 alpha.

Journal ArticleDOI
TL;DR: In this paper, the shell correction method with an average Woods-Saxon potential and a monopole pairing residual interaction was used to calculate the band head excitation energies for odd-Z rare-earth nuclei.

Journal ArticleDOI
TL;DR: Investigation in Greater Copenhagen, Denmark found that the concentration of macromolecular organic floor dust, the floor covering, the number of workplaces in the office, the age of the building, the type of ventilation, and two easily recognizable factors, the shelf factor and the fleece factor, were associated with the prevalence of symptoms of the sick building syndrome.
Abstract: The influence of indoor climate factors on symptoms of the sick building syndrome was investigated in Greater Copenhagen, Denmark. Altogether, 2369 office workers in 14 buildings, where indoor climate measurements were made, filled out a questionnaire. Multivariate logistic regression analyses of the multifactorial effects on the prevalence of work-related mucosal irritation and work-related general symptoms among the office workers showed that the concentration of macromolecular organic floor dust, the floor covering, the number of workplaces in the office, the age of the building, the type of ventilation, and two easily recognizable factors, the shelf factor and the fleece factor, were associated with the prevalence of symptoms.

Journal ArticleDOI
TL;DR: A model for prediction of mortality risk was developed that included five significant preoperative predictive variables; age; patients with history of chronic heart disease, and renal disease; emergency surgery; and the type of operation.
Abstract: The aims of this study were to: 1) determine the incidences and causes of mortality associated with anaesthesia and surgery, 2) identify important factors associated with mortality in hospital, and 3) estimate the mortality risk associated with anaesthesia and surgery when a combination of risk factors are present. A total of 7306 anaesthetized patients undergoing abdominal, urological, gynaecological, or orthopaedic surgery were included in the study. Of these, 0.05% (1:1800) died during anaesthesia, 0.1% (1:730) during the recovery period, and the overall mortality rate in hospital was 1.2% (1:81). Most deaths occurred in the elderly (greater than or equal to 70 years of age) and were unavoidable due to progression of the presenting condition, such as advanced cancer, or co-existing diseases such as cardiopulmonary or renal failure. Of the patients who developed myocardial infarction (MI) following anaesthesia, 67% (8/12) died in the postoperative period. Half of the MI patients who died received regional anaesthesia, and in addition suffered from periods of cardiovascular dysfunction intraoperatively. By utilizing logistic regression analysis, a model for prediction of mortality risk was developed. The model included five significant preoperative predictive variables: age; patients with history of chronic heart disease, and renal disease; emergency surgery; and the type of operation. With this model it is possible to distinguish between patients with very different mortality risks.

Journal ArticleDOI
30 Jun 1990-BMJ
TL;DR: Introducing a partial fee for service system seemed to stimulate the provision of services by general practitioners, resulting in reduced referral rates.
Abstract: OBJECTIVE--To investigate the effects on general practitioners9 activities of a change in their remuneration from a capitation based system to a mixed fee per item and capitation based system. DESIGN--Follow up study with data collected from contact sheets completed by general practitioners in one period before (March 1987) a change in their remuneration system and two periods after (March 1988, November 1988), with a control group of general practitioners with a mixed fee per item and capitation based system throughout. SETTING--General practices in Copenhagen city (index group) and Copenhagen county (control group). SUBJECTS--265 General practitioners in Copenhagen city, of whom 100 were selected randomly from the 130 who agreed to participate (10 exclusions) and 326 general practitioners in Copenhagen county. MAIN OUTCOME MEASURES--Number of consultations (face to face and by telephone) and renewals of prescriptions, diagnostic and curative services, and specialist and hospital referrals per 1000 enlisted patients in one week. RESULTS--Of the 75 general practitioners who completed all three sheets, four were excluded for incomplete data. Total contact rates per 1000 patients listed rose significantly compared with the rates before the change index in the city (100.0 before the change v 111.7 (95% confidence interval 106.4 to 117.4 after the change) and over the same time in the control group (100.0 v 106.0), but within a year these rates fell (to 104.2(99.1 to 109.6) and 104.0 respectively). There was an increase in consultations by telephone initially but not thereafter. Rates of examinations and treatments that attracted specific additional remuneration after the change rose significantly compared with those before (diagnostic services, 138.1 (118.7 to 160.5) and 159.5 (137.8 to 184.7) and curative services 194.6 (152.2 to 248.9) and 194.8(152.3 to 249.2) for second and third data collections respectively) and with the control group (diagnostic services 105.3, 107.6 and curative services 106.0, 115.0) whereas referral rates to secondary care fell (specialist referrals 90.1 (80.7 to 100.6) and 77.0 (68.6 to 86.4) and hospital referrals 87.4 (71.1 to 107.5) and 68.4 (54.7 to 85.4] in doctors in the city. CONCLUSIONS--Introducing a partial fee for service system seemed to stimulate the provision of services by general practitioners, resulting in reduced referral rates. The concept of a "target income" which doctors aim at, rather than maximising their income seemed to play a part in adjustment to changing the system of remuneration.

Journal ArticleDOI
TL;DR: Results indicate that coexistence of myosin heavy chain isoforms in single fibres is present in skeletal muscles of young adults, and that there is an increased occurrence of this phenomenon with ageing.
Abstract: The myosin heavy chain composition of single fibres (n = 1088) was analysed with an electrophoretic technique in biopsy material from m. vastus lateralis (n = 5) and m. biceps brachii (n = 4) of young (23-31 years old) and elderly men (68-70 years old). In m. vastus lateralis, elderly subjects had a higher proportion of fibres showing a coexistence of myosin heavy chain types I and IIa (20 +/- 3% vs 8 +/- 1%, P less than 0.05) and of myosin heavy chain types IIa and IIb (33 +/- 2% vs 12 +/- 4%, P less than 0.05). In contrast, the young subjects had a higher proportion of fibres containing only myosin heavy chain type I (50 +/- 5% vs 33 +/- %, P less than 0.05) and type IIa (26 +/- 3% vs 12 +/- 2%, P less than 0.05). A similar pattern of myosin heavy chain expression was found in single fibres from m. biceps brachii, with the exception that the elderly subjects had a lower proportion of fibres with coexistence of types IIa and IIb (23 +/- 1% vs 34 +/- 2%, P less than 0.05) and a higher proportion of fibres containing only myosin heavy chain type IIa (25 +/- 5% vs 12 +/- 2%, P less than 0.05). Three fibres from m. biceps brachii contained all three isoforms. These results indicate that coexistence of myosin heavy chain isoforms in single fibres is present in skeletal muscles of young adults, and that there is an increased occurrence of this phenomenon with ageing.(ABSTRACT TRUNCATED AT 250 WORDS)

Journal ArticleDOI
TL;DR: This paper presented a comparative analysis of the main research traditions examining the nexus between media and audiences: effects research, uses and gratifications research, literary criticism, cultural studies and reception analysis.
Abstract: This article presents a comparative analysis of the main research traditions examining the nexus between media and audiences: effects research, uses and gratifications research, literary criticism, cultural studies and reception analysis. First presenting short histories of each tradition's roots in the humanities and/or social sciences, the authors then proceed to build a typology of audience studies in terms of theories and modes of enquiry characterizing each tradition. While identifying some controversies arising from different theoretical and political orientations, the analysis also suggests that the current confluence of traditions could be useful for further theoretical, methodological and empirical developments. In particular, cross-cultural, multi-method research would seem to represent a promising avenue for further studies of the mass-media audience.

Journal ArticleDOI
TL;DR: Field and laboratory experiments showed that C. polylepis inhibited the activity of planktonic bacteria, ciliates and copepods during the decay of the bloom, algae were colonized by bacteria and the pycnocline was subsequently re-lnvaded by heterotrophic flagellates, small aloricate ciliate and copEPods.
Abstract: During spring (May-June) 1988 an extensive subsurface bloom of the haptophycean flagellate Chrysochromulina polylepis developed in Scandinavian waters (the KattegatSkagerrak area). Here we report on the vertical distribution of bacteria, heterotrophic flagellates, ciliates and copepods at a permanent station in the Southern Kattegat during the bloom. At the height of the bloom, the density of C. polylepis reached 60 to 70 X 10' cells 1-' in the pycnocline. At this time no potential grazers were present in the subsurface bloom and bacterial production was extremely low. Field and laboratory experiments showed that C. polylepis inhibited the activity of planktonic bacteria, ciliates and copepods. During the decay of the bloom, algae were colonized by bacteria and the pycnocline was subsequently re-lnvaded by heterotrophic flagellates, small aloricate ciliates and copepods. Two weeks after the height of the bloom, the normal pelagic food web structure was re-established.

Journal ArticleDOI
TL;DR: In this paper, the odour thresholds of 24 aroma compounds in Senga Sengana strawberries were determined using duo-trio tests, and the most important compounds were ethyl butanoate, ethyl hexanoate and 2,5dimethyl-4-hydroxy-3(2H)-furanone.
Abstract: The odour tresholds of 24 aroma compounds in Senga Sengana strawberries were determined using duo-trio tests. The threshold values were compared with concentrations in the fruit, and the compounds divided into groups according to their aroma values (concentration/threshold). The most important compounds were ethyl butanoate, ethyl hexanoate and 2,5-dimethyl-4-hydroxy-3(2H)-furanone, but even compounds in concentrations below the threshold values had some influence on the odour.

Journal ArticleDOI
TL;DR: The disappearance of litter after 50–52 days appeared to be due to detritivore activity, since the numbers found below the litter were positively and significantly correlated with the litter disappearance, which indicates thatdetritivores use litter as food, and therefore influence the composition of the litter layer.
Abstract: Litterbag experiments with 10 different kinds of leaf litter showed that detritivore (Lumbricus species) and geophagous (Aporrectodea species) earthworms prefer certain litter types over others, since different numbers of worms were found below the litter after 50–52 days of exposure in a pasture The detritivores preferred Fraxinus, Tilia, and predecomposed Ulmus and Fagus litter to Fagus litter and paper, while geophages preferred Tilia litter to Alnus and Ulmus litter, so that the two groups of earthworms showed different preferences The detritivores seemed to be more selective than the geophages The palatability of the litter was examined in relation to the C: N ratio, the lignin concentration and the initial and final polyphenol concentration The numbers of detritivores were significantly correlated with the C: N ratio and the final polyphenol concentration, so that selection of litter seems to be related to palatability The numbers of geophages were not significantly correlated with any of the parameters for palatability The disappearance of litter after 50–52 days appeared to be due to detritivore activity, since the numbers found below the litter were positively and significantly correlated with the litter disappearance There was no significant correlation with geophage activity This indicates that detritivores use litter as food, and therefore influence the composition of the litter layer

Journal ArticleDOI
TL;DR: The extent of pulmonary complications following anaesthesia and surgery was significantly correlated to patients aged ≥ 70 years, preoperative chronic obstructive lung disease (COLD), major surgery, and to general anaesthesia involving muscle relaxants.
Abstract: The aims of this study were: 1) to describe the frequency and type of cardiopulmonary complications, 2) to identify factors significantly associated with cardiovascular and pulmonary complications associated with anaesthesia and surgery, and 3) to estimate the total risk of cardiopulmonary complications for an anaesthetic when a combination of risk factors is present. Seven thousand three hundred and six anaesthetized patients undergoing gastrointestinal, urological, gynaecological, and orthopaedic surgery were included in the study; 6.3% (1:16) had one or more cardiovascular complications requiring intervention associated with anaesthesia and surgery, and 4.8% (1:21) had pulmonary complications. The total incidence of patients with one or more complications associated with anaesthesia and surgery was 9.4% (1:11). Based on logistic regression analyses, our data indicate that the following patient categories constitute high risk patients with regard to cardiovascular complications: patients aged greater than or equal to 70 years, patients with a history of ischaemic heart disease (IHD) with previous myocardial infarction less than 1 year, a history of chronic heart failure (CHF), and in patients admitted to major surgery. The extent of pulmonary complications following anaesthesia and surgery was significantly correlated to patients aged greater than or equal to 70 years, preoperative chronic obstructive lung disease (COLD), major surgery, and to general anaesthesia involving muscle relaxants. Attempts to estimate the cardiopulmonary complications which may accompany anaesthesia and surgery provided important information about the anaesthetic course and outcome. With our model it seems possible to distinguish between very different levels of cardiopulmonary risk in the anaesthetic patient.