Showing papers by "Aarhus University published in 1989"
1,082 citations
TL;DR: It is suggested that GH, in a conventional replacement dose, has several potentially beneficial effects in GH-deficient adults and therefore encourage future long-term trials.
838 citations
TL;DR: In this paper, a procedure which includes the Total Reduced Inorganic Sulfur (TRIS) in a single distillation step is described for the radiotracer measurement of sulfate reduction in sediments.
Abstract: A procedure which includes the Total Reduced Inorganic Sulfur (TRIS) in a single distillation step is described for the radiotracer measurement of sulfate reduction in sediments. The TRIS includes both Acid Volatile Sulfide (AVS: H2S + FeS) and the remaining Chromium Reducible Sulfur (CRS: S0, FeS2). The single-step distillation was simpler and faster than the consecutive distillations of AVS and CRS. It also resulted in higher (4–50%) sulfate reduction rates than those obtained from the sum of35S in AVS and CRS. The difference was largest when the sediment had been dried after AVS but before CRS distillation. Relative to the35S-AVS distillation alone, the35S-TRIS single-step distallation yielded 8–87% higher reduction rates. The separation and recovery of FeS, S0 and FeS2 was studied under three distillation conditions: 1) cold acid, 2) cold acid with Cr2+, and 3) hot acid with Cr2+. The FeS was recovered by cold acid alone while pyrite was recovered by cold acid with Cr2+. A smaller S0 fraction, presumably of the finer crystal sizes, was recovered also in the cold acid with Cr2+ while most of the S0 required hot acid with Cr2+ for reduction to H2S.
814 citations
665 citations
TL;DR: It is concluded that the acoustic method provides an accurate method for measuring the geometry of the nasal cavity and is potentially useful for investigation of physiological and pathological changes in the nose.
Abstract: To study the geometry of the nasal cavity we applied an acoustic method (J. Appl. Physiol. 43: 523–536, 1977) providing an estimate of cross-sectional area as a function of distance. Acoustic areas...
615 citations
TL;DR: A user‐friendly computer program for calculating inter‐ and intra‐observer agreement of 2 or more observers and recommends the use of the above method before a set of nominal or rank scale parameters are used for deciding prognosis and treatment of patients.
Abstract: Systems for classification and grading used in pathology should ideally be biologically meaningful and at least be reproducible from one pathologist to another. A statistical method to evaluate reproducibility (non-chance agreement) for several observers using nominal or ordinal categories has been developed and refined over the past few decades--the kappa statistic. A high level of observed agreement among different pathologists can either signify a high level of reproducibility, if agreement by chance is low, or express a low level of reproducibility, if agreement by chance is almost as high as the observed agreement. Therefore, the observed agreement says nothing in itself, unless it is low. The kappa value, however, indicates how much better the observers are compared to a throw of the dice, and therefore gives the real credit to the agreement which was found. We have developed a user-friendly computer program for calculating inter- and intra-observer agreement of 2 or more observers. By calculating associations between different categories and different observers, the statistic furthermore obtains a function close to the parameter of accuracy. We recommend the use of the above method before a set of nominal or rank scale parameters are used for deciding prognosis and treatment of patients. By submitting a diskette the computer program will be available at no cost.
429 citations
TL;DR: Improvements in the analysis of lipid-bound phosphates resulted in a simplified and sensitive method for determining microbial biomass in sediments that was both accurate and precise and could be successfully applied to a wider variety of sediment types.
Abstract: Improvements in the analysis of lipid-bound phosphates resulted in a simplified and sensitive method for determining microbial biomass in sediments. Sensitivity was enhanced over previous methods by use of a dye, malachite green, which when complexed with phosphomolybdate at low pH has a high extinction coefficient (at 610 nm). The use of a persulfate oxidation technique to liberate phosphate from lipids increased the simplicity and safety of the method relative to the traditional perchloric acid digestions. The modified method was both accurate (yielding quantitative recoveries of cells added to sediments) and precise (coefficient of variation of less than 5% for cells and sediments). A comparison with an epifluorescence technique indicated that the analysis of lipid-bound phosphate was more rapid and less tedious and could be successfully applied to a wider variety of sediment types. An estimate of the lipid-bound phosphate-to-carbon conversion factor based on a diverse enrichment culture from sediments suggested that previous factors for pure cultures may have been too low.
424 citations
TL;DR: An abnormal diurnal rhythm of AVP seems to be an important pathophysiological factor in enuresis, explaining the abnormally high nocturnal urinary volume and the low noctual urinary osmolality found in these patients.
Abstract: The diurnal variation of plasma vasopressin (AVP), urinary excretion rate, urinary osmolality, and serum osmolality was studied twice in 15 patients with enuresis and in 11 age, weight, and sex matched nonenuretic normal subjects. A diurnal rhythm of AVP with constant levels during the day (8 AM-10 PM) and a highly significant increase during the night (10 PM-8 AM) was found in normal subjects. In contrast, enuretics showed a significantly less pronounced nocturnal increase in AVP with significantly lower nocturnal levels than normal subjects. Normal subjects showed a diurnal rhythm in urinary excretion rate reciprocal to urinary osmolality with a low and highly concentrated nocturnal urinary output. In enuretics, however, this normal diurnal rhythm was absent. In conclusion, an abnormal diurnal rhythm of AVP seems to be an important pathophysiological factor in enuresis, explaining the abnormally high nocturnal urinary volume and the low nocturnal urinary osmolality found in these patients.
422 citations
TL;DR: In this article, the authors present a survey of the state-of-the-art marine science institutions in the United States, including the University of Alaska, Fairbanks, Alaska 99701, U.S.
399 citations
TL;DR: The present study demonstrated clearly a sex-related difference in the changes in vertebral trabecular architecture with age, with a higher tendency to perforation of the horizontal supporting struts in females than in males.
319 citations
TL;DR: The results obtained indicate that the alpha-repeat monomer is composed of regions with different degrees of chromosome specificity.
Abstract: It is demonstrated that either general staining of the centromeric regions of all primate chromosomes, or selective staining of the centromeric region of specific chromosomes, may be obtained in preparations of metaphase chromosomes by probing specifically for different regions within the alpha satellite DNA monomer. In order to exploit observed patterns of sequence variation within the monomer for this purpose, we have developed two new DNA analysis methods. In PRimed IN Situ labelling (PRINS), synthetic oligonucleotides derived from subsections of the monomer are hybridized to the chromosomes. The oligonucleotides then serve as primers for the in situ incorporation of biotin-labelled nucleotides catalysed by Klenow polymerase. Incorporated biotin is visualized with fluorescein isothiocyanate-labelled avidin (FITC-avidin). In Primed Amplification Labelling (PAL), biotin-labelled hybridization probes are produced in a polymerase chain reaction (PCR, Saiki et al. 1985), in which two synthetic oligonucleotide primers anneal within the same monomer. With the right choice of primers libraries of labelled probes derived from most monomers present as templates are produced. If DNA from a specific chromosome is used as template, then the resulting probe mixture gives stronger and more chromosome-specific signals in in situ hybridization experiments than does a cloned alpha satellite DNA probe derived from the same chromosome. The results obtained indicate that the alpha-repeat monomer is composed of regions with different degrees of chromosome specificity.
01 Sep 1989
TL;DR: Although the notion of virtual class originates from BETA, it is presented as a general language mechanism where they provide a mechanism for defining general parameterized classes such as set, vector and list.
Abstract: The notions of class, subclass and virtual procedure are fairly well understood and recognized as some of the key concepts in object-oriented programming. The possibility of modifying a virtual procedure in a subclass is a powerful technique for specializing the general properties of the superclass.In most object-oriented languages, the attributes of an object may be references to objects and (virtual) procedures. In Simula and BETA it is also possible to have class attributes. The power of class attributes has not yet been widely recognized. In BETA a class may also have virtual class attributes. This makes it possible to defer part of the specification of a class attribute to a subclass. In this sense virtual classes are analogous to virtual procedures. Virtual classes are mainly interesting within strongly typed languages where they provide a mechanism for defining general parameterized classes such as set, vector and list. In this sense they provide an alternative to generics.Although the notion of virtual class originates from BETA, it is presented as a general language mechanism.
TL;DR: It is suggested that anoxygenic photosyn-thesis is a relatively recent phenomenon in the Black Sea initiated by shallowing of the chemocline over the past decade and develop-ment of an anoxic layer devoid of O2 and H2S (ref. 7).
Abstract: The contribution of anoxygenic photosynthesis to carbon cycling in the Black Sea, the world's largest body of anoxic marine water, has been vigorously investigated and debated for over four decades. Penetration of light into the sulphide-containing deep water may result in a zone of anaerobic primary production by photosynthetic bacteria. We report here the results of analyses of photosynthetic pigments in samples of suspended particulate matter collected from two stations in the western basin of the Black Sea. Our data demonstrate high concentrations of a bacterio-chlorophyll at the chemocline, and thus the potential for anoxygenic photosynthesis as a component of primary production in the carbon cycle of the Black Sea. More than 95% of the pigments in the bacteriochlorophyll-maximum are accounted for by a series of aromatic carotenoids and bacteriochlorophylls-e, including a previously unreported geranyl ester of 4-i-butyl bacteriochlorophyll-e. The distribution of pigments is characteristic of the obligate phototrophs Chlorobium phaeobacteroides and C. phaeovibriodes. Total depth-integrated bacteriochlorophyll at one station exceeded total chlorophyll-a in the overlying oxygenated portion of the euphotic zone. We suggest that anoxygenic photosynthesis is a relatively recent phenomenon in the Black Sea initiated by shallowing of the chemocline over the past decade and development of an anoxic layer devoid of O2 and H2S.
TL;DR: A framework for the design of user interfaces that originates from the work situations in which computer-based artifacts are used is presented and it is argued that the user interface fully reveals itself to us only when in use.
Abstract: How can we understand why a bank teller has different needs for a user interface than those of casual users of a machine teller, or why a graphic designer needs a different user interface than a secretary? This article presents a framework for the design of user interfaces that originates from the work situations in which computer-based artifacts are used: The framework deals with the role of the user interface in purposeful human work. Human activity theory is used in this analysis. The purpose of this article is to make the reader curious and hopefully open his or her eyes to a somewhat different way of thinking about the user interface. The article applies examples of real-life interfaces to support this process, but it does not include a systematic presentation of empirical results.
I focus on the role of the computer application in use. Thus, it is necessary to consider human-computer interaction and other related work conditions. I deal with human experience and competence as being rooted in the practice of the group that conducts the specific work activity.
The main conclusions are: The user interface cannot be seen independently of the use activity (i.e., the professional, socially organized practice of the users and the material conditions for the activity, including the object of the activity). The standard view in these situations is to deduce an ultimate set of operations from an abstract use activity and apply these to design and analysis. This article argues that the user interface fully reveals itself to us only when in use. What is a good user interface for those with a certain degree of competence may not be efficient for those with different levels of competence. I give certain general recommendations for the user interface, but I have no guarantee that such recommendations are applicable to the specific case wherein these concerns may be overruled by specific social or material concerns.
TL;DR: The amino acid sequence of a 90-residue segment of human pregnancy zone protein containing its bait region has been determined and the evolutionary constraints for these regions are likely to differ from those of the remainder of the alpha-macroglobulin structure.
TL;DR: A general theory of random tessellations (i.e. stochastic aggregates of disjoint and space-filling cells) in d-dimensional Euclidean space is presented.
Abstract: This paper presents a general theory of random tessellations (i.e. stochastic aggregates of disjoint and space-filling cells) in d-dimensional Euclidean space. Some particular models of random tessellations are discussed in detail.
TL;DR: In this paper, the Markov point processes introduced by Ripley & Kelly are generalised by replacing fixed-range spatial interactions by interactions between neighbouring particles, where the neighbourhood relation may depend on the point configuration.
Abstract: Summary The Markov point processes introduced by Ripley & Kelly are generalised by replacing fixed-range spatial interactions by interactions between neighbouring particles, where the neighbourhood relation may depend on the point configuration. The corresponding HammersleyClifford characterisation theorem is proved. The results are used to construct new models for point processes, multitype point processes and random processes of geometrical objects. Monte Carlo simulations of these models can be generated by running spatial birth-and-death processes.
01 Sep 1989
TL;DR: The correctness of the model is demonstrated by proving it equivalent to an operational semantics of inheritance based upon the method-lookup algorithm of object-oriented languages.
Abstract: This paper presents a denotational model of inheritance. The model is based on an intuitive motivation of the purpose of inheritance. The correctness of the model is demonstrated by proving it equivalent to an operational semantics of inheritance based upon the method-lookup algorithm of object-oriented languages. Although it was originally developed to explain inheritance in object-oriented languages, the model shows that inheritance is a general mechanism that may be applied to any form of recursive definition.
TL;DR: In this paper, a configuration-interaction energy function (Lagrange) which is variational in all variables, including the orbital rotational parameters, is constructed, and the relationship between the numerical errors in the variational parameters and the errors in calculated energy derivatives is discussed.
Abstract: A configuration-interaction energy function (Lagrange) which is variational in all variables, including the orbital rotational parameters, is constructed. When this Lagrangian is used for obtaining configuration-interaction derivatives, all the important simplifications which occur for derivatives of variational wave functions carry over in a straightforward way. In particular, the state and orbital rotational response parameters obey the 2n+1 rule and the Lagrange multipliers obey the somewhat stronger 2n+2 rule. The simplifications which are normally obtained by invoking the Handy-Schaefer technique are automatically incorporated to all orders. Simple expressions for energy derivatives up to third order are presented. The relationship between the numerical errors in the variational parameters and the errors in the calculated energy derivatives is discussed.
TL;DR: The effect of the boundary conditions between trabecular bone specimens and the test columns of the testing machine was studied together with the effect of side-constraint on the mechanical behaviour of trabECular bone during axial compression to show changes in stiffness and energy dissipation.
TL;DR: The material investigated was the first lumbar vertebra obtained from two females and six males with ages 26 to 75 years without malignant or metabolic bone diseases, and results did show a highly significant, five-fold increase in the star volume of the marrow space with age; no such age correlation was found for the starVolume of the trabeculae.
TL;DR: The cross‐sectional area of the nasal cavity as a function of distance from the nostrils was obtained and acoustic rhinometry was introduced as a new, objective method to assess the geometry of the nose.
Abstract: We introduce acoustic rhinometry as a new, objective method to assess the geometry of the nasal cavity. The cross-sectional area of the nasal cavity as a function of distance from the nostrils was obtained. A group of 21 patients with septal deformities was examined with acoustic rhinometry preoperatively and postoperatively. These values were compared with those of 21 normal control subjects. The minimal cross-sectional area (MCA) is located in the anterior part of the nose, and it shifts anteriorly under the effect of decongestion. The preoperative value of MCA is related to the location and severity of the anterior septal deformity. Postoperative smaller MCA found in the opposite side of that narrowed by a severe anterior septal deformity may be explained by the impact of septoplasty without reduction of a hypertrophic turbinate. A highly significant relation between MCA and the subjective feeling of nasal patency, before and after surgery, suggests that MCA is a valuable parameter to express nasal patency. Correction of posterior septal deformities is found to increase significantly the cross-sectional area posteriorly. The effect of decongestion in the postoperative values, however, suggests that the mucosa contributes even more to the cross-sectional area of the posterior part of the nose. Acoustic rhinometry seems very suitable for evaluation of the nasal cavity in cases where septoplasty and turbinoplasty is considered, as well as for the postoperative evaluation.
TL;DR: Quinoxalinediones have been used to demonstrate that non‐NMDA receptors mediate the majority of the EPSP, indicating that NMDA receptors participate in monosynaptic excitation.
Abstract: 1. The effects of new, potent non-N-methyl-D-aspartate (NMDA) receptor antagonists, 6,7-dinitroquinoxaline-2,3-dione (DNQX) and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), have been examined using intra- and extracellular recordings in the hippocampal slice preparation. In terms of potency and selectivity, the action of the two blockers was similar and CNQX was used in most experiments. 2. CNQX reduced the responses to ionophoretic applications of the non-NMDA agonists kainate (KAI) and quisqualate (QUIS) with IC50 values of 1.2 and 4.8 microM, respectively. In Mg2+-free solutions responses to NMDA were generally not affected by concentrations of CNQX up to 25 microM. 3. The action of CNQX was only slowly and poorly reversible on washing. Responses to QUIS and KAI were also reversibly reduced by ionophoretic application of CNQX. 4. CNQX blocked the evoked EPSP in CA1 and CA3 neurones with an IC50 of around 2 microM, which is similar to the IC50 for responses to KAI. CNQX was without effect on the passive membrane properties, the afferent volley and paired pulse potentiation. 5. In the presence of CNQX (greater than 5 microM) a small EPSP remained which was largest in CA1 neurones. It was blocked by low concentrations of the NMDA receptor antagonist (+/-)-2-amino-5-phosphonovaleric acid (APV), was markedly enhanced on removing Mg2+ ions from the bathing medium and, in voltage-clamp experiments, showed a potential dependence which is characteristic of the NMDA ionophore. 6. The latency of the APV-sensitive EPSP in CA1 was the same as the CNQX-sensitive EPSP, indicating that NMDA receptors participate in monosynaptic excitation. 7. Feedback and feed-forward inhibition in both area CA1 and CA3 were sensitive to CNQX. There seemed to be two components of the inhibition, both of which appear to be GABAergic since they could be blocked by picrotoxin (PTX), but only one of which was blocked by CNQX. The CNQX-resistant IPSP was not affected by APV. 8. In conclusion, quinoxalinediones have been used to demonstrate that non-NMDA receptors mediate the majority of the EPSP. Additionally, a component of the EPSP in CA1 is mediated by NMDA receptors and is manifested at resting membrane potentials and in the presence of Mg2+.
TL;DR: It is demonstrated that calcipotriol ointment provides an effective and well-tolerated treatment of psoriasis vulgaris.
Abstract: Calcipotriol (the synthetic compound MC 903) is a structural analogue of naturally occurring, biologically active calcitriol. Calcipotriol and calcitriol (1,25-dihydroxy vitamin D3) show similar receptor binding and comparable effects on cell differentiation. However, calcipotriol seems to be at least 100 times less potent in its effects on calcium metabolism. In a double-masked study involving 50 patients with psoriasis vulgaris, the efficacy and tolerability of ointments containing various calcipotriol concentrations (25, 50, or 100 micrograms/g) or the vehicle alone were compared in a study involving a right-left, within-patient randomized design. Patients were treated twice daily for 8 weeks. Marked improvement was seen in 40% of the patients treated with the 25-micrograms/g concentration of calcipotriol in 63% of patients treated with the 50-micrograms/g concentration, and in 88% treated with the 100-micrograms/g concentration. No patient treated with placebo had more than slight improvement. Five patients developed facial dermatitis during the study. The serum levels of ionized calcium were unchanged. This study demonstrates that calcipotriol ointment provides an effective and well-tolerated treatment of psoriasis vulgaris.
TL;DR: The results greatly expand the repertoire of sequences known to be cleaved by fibroblast collagenase and suggest that this proteinase has a primary substrate specificity resembling that of the microbial proteinase thermolysin, as it preferentially cleaves at the NH2-terminal side of large hydrophobic residues.
TL;DR: In this article, a comparative survey of radiolabeled end-products during 35S0,2reduction measurements in coastal sediments of Denmark is presented, showing that 35S recovery in acidvolatile sulfides (AVS), pyrite, and elemental sulfur in the upper O-15 cm of sediment depended on the sulfur chemistry and on the overall sulfate reduction rates.
Abstract: A comparative survey was done of the formation of radiolabeled end-products during 35S0,2reduction measurements in coastal sediments of Denmark. The distribution of reduced 35S in acidvolatile sulfides (AVS), pyrite, and elemental sulfur in the upper O-15 cm of sediment depended on the sulfur chemistry and on the overall sulfate reduction rates. In sediments with relatively low metabolic rates, undetectable H,S, and low FeS : FeS, ratio ( 1 : lo), the 35S recovery in AVS was 63-92%. The relative contribution of Fe35S2 formation showed little depth dependence, whereas the formation of 35So was highest in the more oxidizing sediment layers near the surface. Inclusion of 35S-labeled FeS, and So in the sulfate reduction measurement yields more accurate rate data than are obtained from AVS alone. Due to possible isotopic exchange reactions and unknown pathways of H,S transformation into AVS, So, and FeS,, however, the radioactivities of the three pools cannot be used directly to calculate their differential rates of formation.
TL;DR: The results suggest that the ability of a drug to control vascular structure during treatment is not in itself a predictor of a persistent effect on blood pressure after withdrawal of treatment, and pointed to the usual close relationship between vascular structure and blood pressure in the absence of treatment.
Abstract: We have studied the effects of long-term treatment with different antihypertensive drugs on blood pressure and mesenteric resistance vessel structure of spontaneously hypertensive rats (SHR), both during treatment and after withdrawal of treatment. Young SHR were treated from 4 to 24 weeks with five different drugs: perindopril (1.5 mg/kg per day), captopril (60 mg/kg per day), hydralazine (25 mg/kg per day), isradipine (42 mg/kg per day) and metoprolol (130 mg/kg per day). At 24 weeks, 24-h mean blood pressures (MBP), measured invasively, were 121 mmHg (perindopril), 137 mmHg (captopril), 140 mmHg (hydralazine), 149 mmHg (isradipine) and 146 mmHg (metoprolol), compared to control values of 177 mmHg (SHR) and 132 mmHg (Wistar-Kyoto rats, WKY). Mesenteric resistance vessel structure, measured as media:lumen ratio (m:l), was also reduced to different extents: to WKY-level by perindopril (m:l = 4.4%), to midway between SHR- and WKY-levels by captopril, hydralazine and isradipine (m:l = 5.9%), and not at all by metoprolol (m:l = 6.8%). When treatment was discontinued, low MBP (ca 151 mmHg) persisted for 12 weeks in rats treated with the angiotensin converting enzyme inhibitors (perindopril and captopril), but rose rapidly in rats which had received the other treatments. At 3-12 weeks after withdrawal of treatment vascular structure was closely correlated with the blood pressure expected from the SHR- and WKY-control values, as were the left ventricle: body weight ratios. The results suggest that the ability of a drug to control vascular structure during treatment is not in itself a predictor of a persistent effect on blood pressure after withdrawal of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
Journal Article•
TL;DR: In this paper, the authors present the major steps of a mathematical procedure that permits the simulation of Electron Channeling Pattern (CP) maps of any mineral species for which unit-cell constants, the atomic species and their equivalent positions are known.
Abstract: The paper presents the major steps of a mathematical procedure that permits the simulation of Electron Channeling Pattern @CP) maps of any mineral species for which unit-cell constants, the atomic species and their equivalent positions are known. The basis of calculation is the Bragg equation, the structure factor d and the atomic scattering factors of the atomic species. Simulated spherical ECP maps for chromite and quartz are presented and compared to traditional ECP maps, which were constructed from ECP photomicrographs, good results. The fraction of the ECP sphere that covers all possible orientations of a crystal is discussed for all 32 point groups. It is shown that Lauegroup symmetry is the determining factor, which results in a loss of "resolution" in certain point groups. The ECP simulation leads to the creation of a software package CHANNEL, which permits rapid ECP-pattern recognition and lattice-orientation determination, in principle without the need for previous construction of an ECP map.