showing 36 of ~574560 from 574555 documents
Über die Micromelerpetontidae (Amphibia: Temnospondyli). 1. Morphologie und Paläoökologie desMicromelerpeton credneri (Unter-Perm; SW-Deutschland)
1995
This paper presents a redescription of the most important features of the skull roof, palate, hyobranchial apparatus, and the postcranial skeleton ofMicromelerpeton credneri. It is possible to distinguish a temporal sequence of three morphotypes that can be differentiated by size and slight differences in the structure of the skull roof. They led a predaceous existence in the pelagial of three fairly deep lakes that had excellent potential for the preservation of fossils. Comparisons of the size-frequency distributions for specimens from different horizons indicate facultative paedomorphosis by means of progenesis. This phenomenon may be related to different trophic strategies and possible …
Synthesis, characterization, and crystal structure of [Cu(cinoxacinate)2] · 2H2O complex: A square-planar CuO4 chromophore. Antibacterial studies
1995
The structural and spectroscopic properties of a new copper (II) complex of cinoxacin (HCx) have been investigated. The complex [Cu(Cx)2].2H2O crystallizes in the monoclinic system, space group P2(1)/c. The cell dimensions are: a = 7.998(2), b = 7.622(1), c = 18.955(6) A, beta = 94.38(2) degree, V = 1154.6(6) A3, Z = 2. The structure was refined to R = 0.051. The crystal is composed of [Cu(Cx)2] units and uncoordinated water molecules. The Cu(II) ion, at a center of symmetry, is coordinated to two cinoxacinate (Cx) ligands related by the inversion center. Each cinoxacinate acts as bidentate ligand bonded to the cation through its carboxylate oxygen atom and through its exocyclic carbonyl ox…
Presence of Pomphorhynchus laevis in Salamandra salamandra
1995
AbstractInfection of Salamandra salamandra larvae (Amphibia: Urodela) with the fish acanthocephalan Pomphorhynchus laevis was detected in a fish-free mountain brook. Gammarus fossarum was found to be the intermediate host. The parasites were probably inadvertently introduced through fish breeding practices. Evidence was obtained that Pomphorhynchus laevis persists, at least for several months, in postmetamorphic fire salamanders.
Interest rates, expectations and the credibility of the Bank of Spain
1995
The purpose of the paper is to pinpoint the date of the change of monetary policy regime which occurred in Spain during the year 1984, when it moved away from controlling monetary aggregates towards interest rate targeting. The most likely date for the change is estimated and, surprisingly, there is evidence that agents learned about the new intermediate target quite rapidly.A week after the change, the term structure of interest rates showed how market agents attributed much more informational content to interest rate changes than they had previously. Two types of transitions are tried: a one-step and a gradual logistic swithing function.
A mixed geometric-systolic approach to parallel molecular dynamics simulations
1995
We have developed a flexible and efficient method of performing molecular dynamics simulations on distributed memory parallel computers. The novel feature is to use simultaneously spatial partitioning and systolic loop approaches according to a strategy which, for a given simulation, adapts itself to the multiprocessor system, allowing to approach optimal performance. The method assures high efficiencies even in situations in which, due to the exceeding large number of processors, the usage of a pure spatial decomposition would be impossible. The algorithm provides as particular cases both the pure spatial partitioning and the pure systolic parallelization schemes, so that its adoption assu…
Echelles biostratigraphiques du Meso-Cenozoique, ouest-europeen; synthese, applications et perspectives--The Meso-Cenozoic biostratigraphic framework…
1995
Time-dependent changes in serum 3α-androstanediol glucuronide correlate with hirsutism scores after ovarian suppression
1995
The clinical utility of serum 3 alpha-androstanediol glucuronide level has been controversial. Among the concerns regarding its lack of utility has been the finding that suppression of serum 3 alpha-androstanediol glucuronide does not occur readily with treatment. We hypothesized that because the treatment of hirsutism requires a prolonged duration, a longer observation period is required for changes in serum 3 alpha-androstanediol glucuronide to be measured. Therefore, we studied the clinical and hormonal changes in 11 women treated for hirsutism with a gonadotropin-releasing hormone agonist (GnRH-a) for 1 year. A progressive reduction in Ferriman-Gallwey scores occurred, which was signifi…
The self-narrative and acute psychosis
1995
The aim of this study was to apply the narrative approach in analyzing family therapy meetings in cases of acute psychosis. The self-narrative is essential in acute psychosis since it is either collapsed or not coherent enough. The results indicate that it is important to create concrete practices that produce stories concerning the patient in relation to others. The self-narrative must be re-authored by the patient even though it is socially constructed. This is achieved by creating multiple perspectives of self-narratives in so-called therapy meetings with the patient, family members, and staff members representing different professionals.
Tunneling in a ?breathing? double well: Adiabatic and antiadiabatic limits and tunneling suppression
1995
Tunneling in a piecewise harmonic potential coupled to a harmonic oscillator is considered by means of the path integral technique. The reduced propagator for the tunneling particle is calculated explicitly and the tunneling splitting is found in semiclassical approximation. The result holds for arbitrary values of the parameters of the system. From this the adiabatic and antiadiabatic approximations are obtained as particular cases and compared with the results obtained differently. The limit of a strong interaction is also considered. It is found that for strong interaction or equivalently for the harmonic frequency tending to zero the preexponential factor in the tunneling splitting tend…
Europe spreads its wings
1995
In The early 1960s a number of European governments, in consultation with scientists, engineers and industrialists, decided to enter space. To compete with the superpowers was, of course, out of the question – Europe had neither the resources nor the political interest to get involved in the space race. It was deemed possible, however, to pool the resources of the most industrialized European nations to support a limited effort in this important scientific and technological field.
Tunable axial superresolution by annular binary filters. Application to confocal microscopy
1995
We present a set of annular binary pupil filters for increasing the axial resolving capacity of imaging systems. The filters consist of two transparent annuli of the same area. It is shown that by changing the area of the transparent regions it is possible to obtain a tunable reduction of the width of the central lobe of the axial point spread function of the imaging system. However, this reduction is accompanied by a severe increase of the strength of secondary lobes, what can make these filters not very useful when used in conventional imaging systems. That is why we propose to use these filters for apodizing confocal microscopy systems. It is shown that in this case an important reductio…
Nucleon polarization in exclusive deuteron electrodisintegration with polarized electrons and a polarized target
1995
Nucleon polarization in exclusive electrodisintegration of the deuteron using a polarized beam and an oriented target is systematically investigated in a nonrelativistic framework but with lowest order relativistic contributions to the one-body current including the kinematic part of the wave function boost. The structure functions and the asymmetries corresponding to the various nucleon polarization components are studied with respect to their sensitivity to the potential model, to subnuclear degrees of freedom, and to relativistic effects in different kinematical regions. Furthermore, a few new observables are found which are very sensitive to the neutron electric form factor ${\mathit{G}…
Tectonic and lithological constraints on the evolution of the Karoo graben of northern Malawi (East Africa)
1995
The results of a lithostratigraphic, tectonic and kinematic study of the Karoo deposits of northern Malawi are reported. The objective of the lithostratigraphic study is to correlate the deposits of the Karoo basins of northern Malawi with the well-known deposits of southern Tanzania, thus establishing a stratigraphic framework through which the timing of faulting can be constrained. The kinematic analysis of faulting constrains the opening direction for the Karoo graben in this area and provides basic data to discuss the Karoo graben development within the regional tectonic framework of south-eastern Africa. The studied adults are defined by moderately to steeply dipping cataclastic zones …
Bone morphogenetic protein-4 is required for mesoderm formation and patterning in the mouse.
1995
Bone morphogenetic protein-4 (BMP-4) is a member of the TGF-beta superfamily of polypeptide signaling molecules, closely related to BMP-2 and to Drosophila decapentaplegic (DPP). To elucidate the role of BMP-4 in mouse development the gene has been inactivated by homologous recombination in ES cells. Homozygous mutant Bmp-4tm1blh embryos die between 6.5 and 9.5 days p.c., with a variable phenotype. Most Bmp-4tm1blh embryos do not proceed beyond the egg cylinder stage, do not express the mesodermal marker T(Brachyury), and show little or no mesodermal differentiation. Some homozygous mutants develop to the head fold or beating heart/early somite stage or beyond. However, they are development…
Structure of the highly deformed nucleus101Sr63 and evidence for identical K=3/2 bands
1995
The low-energy level scheme of theN=63 nucleus101Sr has been obtained from a β-decay study of101Rb. The ν[532]5/2 and ν[411]3/2 orbitals are well established as the ground state and a band head at 271.2keV, respectively. The general properties of the level scheme indicate a quadrupole deformation ofβ ≃ 0.4, confirming the unique feature of saturation of deformation inN ≥ 60 Sr isotopes. The energies of theK=3/2 intraband transitions in the odd-neutron neighbours99Sr61 and101Sr63 are very similar. More generally, the identical bands at low spin in98–101Sr nuclei are correlated with the mass-independent moments of inertia in this region.
Local disequilibrium of plagioclase in high-temperature shear zones of the Ivrea Zone, Italy
1995
Microstructural and chemical analysis of plagioclase in 20 superficially similar amphibolite facies ductile shear zones in metagabbors and amphibolites of the Ivrea Zone in Italy reveals significant differences in An and Ba contents. Plagioclase, which was deformed at P-T conditions lower than those of the wall rocks, occurs in the following four different microstructural situations with different chemical compositions: (i) relatively undeformed porphyroclasts, (ii) dynamically recrystallized grains and subgrains rimming the porphyroclasts, (iii) infill of microcracks cross-cutting the porphyroclasts and (iv) fine-grained recrystallized grains in the matrix of the shear zones. The differenc…
Fertilization and early embryology: Morphometric characterization of normal and abnormal human zygotes
1995
Human zygotes (n = 278) from 96 in-vitro fertilization gonadotrophin-stimulated cycles were photographed in their pronuclear stage (16-18 h post-insemination). Normal morphological fertilization (two pronuclei) was observed in 215 zygotes, 17 showed only one pronucleus, 40 showed three pronuclei and six showed four. Area, perimeter and maximum and minimum diameters of each zygote and pronucleus were measured using an IBAS 2000 (Kontron) image analyser. When the four groups were compared, whole zygotes did not show any morphometric difference. However, pronuclei from these groups showed that a high number of pronuclei was directly related to small pronuclei. Differences in pronuclear size an…
Long-term deformation and fluid-enhanced mass transport in a Variscan peridotite shear zone in the Ivrea Zone, northern Italy: a microtextural, petro…
1995
The microtextural, petrological and geochemical study of a ductile shear zone in the phlogopite peridotite of Finero/Ivrea Zone (northern Italy) reveals the long-term deformation of this zone. The zone is divided into a protomylonitic and an ultramylonitic part. Both parts reflect different periods of deformation, although the orientation of the mineral lineations does not change. In the coarse-grained part (period 1) the deformation started under granulite facies conditions (about 775°C). Olivine, ortho- and clinopyroxene and phlogopite recrystallized dynamically. In the ultramylonitic part relics of the granulite facies event and evidence for a continuous or two-stage deformation history …
Effects of streptozotocin-induced diabetes, physical training and their combination on collagen biosynthesis in rat skeletal muscle.
1995
The effects of streptozotocin-induced diabetes, physical training and their combination on the activities of prolyl 4-hydroxylase (PH) and galactosylhydroxylysyl glucosyl-transferase (GGT), both marker enzymes of collagen biosynthesis, and on the concentration of hydroxyproline (Hyp) were studied in vastus lateralis, rectus femoris and gastrocnemius muscles in rats. The experimental period was 12-16 weeks. Diabetes had an overall decreasing effect on specific PH activity in all muscles studied, whereas specific GGT activity remained at control level. Total PH and GGT activities decreased in all three muscles in the diabetic animals (P < 0.001). Training caused an increase in PH and GGT acti…
Rat Plasma VLDL Composition and Concentration and Hepatic Lipase and Lipoprotein Lipase Activities Are Impaired during Two Types of Protein Malnutrit…
1995
The relationships between VLDL concentrations and composition and changes in hepatic lipase and lipoprotein lipase activities were determined in rats, during the consumption of two low protein diets (2% casein or 5% gluten) (protein malnutrition) for 28 d, followed by the refeeding of a balanced diet for 14 d (15% casein) (refeeding). A control group was fed 15% casein for 42 d. In the control group, total lipolytic activity increased with age (r = 0.83, P < 0.001), whereas in both depleted groups, this activity remained low and stable throughout the period of protein malnutrition. At d 28 of protein malnutrition, plasma total lipolytic activities were significantly reduced in both depleted…
Bilateral agenesis/aplasia of the lungs: report of a second case in the offspring of one woman.
1995
Congenital absence of both lungs is an extremely rare malformation in humans and is thought to occur sporadically. We report the second case of congenital absence of both lungs in the offspring of one woman. In neither case, one female baby (born at term) and one aborted female fetus (21 weeks of gestation), were anomalies or malformations of other organ systems observed. The karyotype of the aborted fetus was 46,XX. To our knowledge, this is the first report describing bilateral pulmonary agenesis in two offspring of one mother. The repetition of virtually the same isolated abnormality with no other malformations supports the hypothesis that it could be caused by a genetic disorder. Other …
Description of x-ray beams using the fluorescence yields of a set of thick targets
1995
Quantitative methods in x-ray fluorescence analysis require a knowledge of the spectral distribution of the fluorescence-exciting beam. The use of XRF yield measurements of a set of thick pure element targets is proposed for the description of a fluorescence-exciting x-ray beam, without the need to obtain its spectral distribution. This new approach is derived theoretically and verified by comparing thin-target yields calculated from XRF yield measurements of thick pure element specimens with those obtained from a calculated spectral distribution. The difference between the two methods of obtaining the thin-target yields is within 9% relative error.
Interferon-alpha (IFN-alpha) inhibits granulocyte-macrophage colony-stimulating factor (GM-CSF) expression at the post-transcriptional level in murin…
1995
Recently it has been shown that IFN-alpha inhibits expression of GM-CSF in adherent cells of human long-term bone marrow cultures (LTBMC) stimulated with interleukin-1 (IL-1), tumour necrosis factor-alpha (TNF-alpha) or endotoxin. The murine bone marrow stromal cell line +/+(-1).LDA11 was used to further define regulatory mechanisms of IFN-alpha inhibition on GM-CSF expression. This cell line originated from a murine Dexter type culture and exhibits a preadipocytic phenotype. As in human LTBMC, we could demonstrate a inhibitory effect of IFN-alpha co-incubation on GM-CSF activity in serum-free supernatants of +/+(-1).LDA11 stromal cell cultures stimulated with IL-1 or TNF-alpha or the combi…
Visible but unreported: a case for the "not serious enough" cases of child maltreatment.
1995
This study examined the psychosocial characteristics of cases of child maltreatment labelled as "not serious enough." The sample consisted of cases of suspected physical abuse (N = 48), neglect (N = 13), and psychological maltreatment (N = 8) identified by teachers, and a nonabused comparison group (N = 283). Characteristics of children and their parents were evaluated at three ecological levels: individual, family, and social. Results indicated a poor personal and social adjustment of the children in the maltreatment groups, and suggest that the definition of cases of maltreatment as not serious enough does not represent the psychological reality of these children. Discriminant analysis in…
Differences in allozyme patterns between Diaphanosoma brachyurum and Diaphanosoma mongolianum, as revealed in Central European populations
1995
Recent taxonomic revisions in the genus Diaphanosoma have made the uncertainty in species discrimination with morphological characters obvious. Therefore species characterization on a genetic basis seems to be required. Here we examined the genetic structure of two Diaphanosoma mongolianum populations and three Diaphanosoma brachyurum populations in Central Europe by allozyme electrophoresis. A genetic differentiation between both species was evident. 5 out of 9 tested loci carried diagnostic alleles. Both species differed in their habitat choice: D. mongolianum was adapted to higher trophic levels than D. brachyurum. Co-occurrence was observed in a eutrophic lake. Populations sampled from …
Machining of Steel with Advanced Ceramic Cutting-Tools
1995
Cephalopods in the diet of the striped dolphin Stenella coeruleoalba from the western Mediterranean during an epizootic in 1990
1995
Fifteen cephalopod species from 28 stomach contents of striped dolphins, Stenella coeruleoalba (Meyen, 1833), stranded during an epizootic on the western Mediterranean coast in summer 1990, were analysed. Albraliopsis pfefferi, Onychoteuthis banksii, Todarodes sagittatus and Brachioteuthis riisei are species showing higher relative importance indices. Composition and characteristics of cephalopod preys were discussed and compared to the scarce literature for this cetacean. The data showed a mixed diet of muscular and gelatinous body squids, mainly consisting of oceanic and pelagic or bathypelagic species.
Malignant transformation of the liver tumour precursor cell line OC/CDE 22 by the four stereoisomeric fjord region 3,4-dihydrodiol 1,2-epoxides of be…
1995
In previous work we established the rat liver oval cell line OC/CDE 22 in order to study in vitro mechanisms of liver cell transformation. We have now exposed OC/CDE 22 cells to each of the four optically active fjord region dihydrodiol epoxides of benzo[c]phenanthrene to investigate their capacity for malignant transformation of liver cells. All four configurational isomers, which are among the most potent carcinogenic metabolites of polycyclic aromatic hydrocarbons tested in murine tumour models, malignantly transform OC/CDE 22 cells at a 2 microM dose level, resulting in a similar colony-forming efficiency in soft agar. Inoculation of the transformed cells into newborn syngeneic rats pro…
Electrochemical study of intramolecular charge transfer complexes derived from 1,4-naphthoquinone Part 1. Electroreduction
1995
Abstract Electrochemical investigations (polarography, cyclic voltammetry, rotating ring-disk electrode voltammetry) of intramolecular charge transfer complexes (AC) derived from 1,4-naphthoquinone were performed in acetonitrile. It is concluded that in the first one-electron stage of its electrochemical reduction the AC is in a complexed form. At the same time the amino moiety, which shows a marked inductive (−I) effect, acts as an electron donor in the donor-acceptor (D-A) interaction. Facilitation of the reduction of the quinone part by the aryl amine residue is compensated by the D-A interaction, which makes the electroreduction more difficult. By using ultramicroelectrodes it was shown…
A Note on Locally ??-compact Spaces
1995
: The local version of the concept of ℰτ-compactness (where ℰ is a class of Hausdorff spaces and ℰ is a cardinal) introduced by the first author as a generalization of Her-rlich's concept of ℰ-compactness (and hence, also of Mrowka's E-compactness) is defined and the corresponding theory is initiated. An essential part of the theory is developed under the additional assumption that all spaces from ℰ are absolute extensors for spaces under consideration. The theory contains as a special case the classical theory of local compactness.
Convolution operators with a fundamental solution of finite order
1995
Influence of dissolved humic material and ionic strength on C8 extraction of pesticides from water
1995
A mixture of twelve intermediate polarity pesticides, mostly carbamate-type, have been chromatographied on an octadecyl-silica bonded-phase column using acetonitrile-water gradient mobile phase and UV detection. Pesticides were extracted from aqueous matrix by solid-phase extraction. The extraction system consisted of a glass microcolumn containing octyl-silica solidphase conditioned with methanol and water. The elution was by acetonitrile-dichloromethane (50:50). Studies of extraction factors like volume of sample, addition of 10% sodium chloride and presence of dissolved humic material are investigated.
Ring inversion pathways of exo- and endo-calix[4]arenes studied by means of the MM3 force field
1995
Abstract The ring inversion pathways of an exo-calix[4]arene 1a and of p-tert-butylcalix[4]arene 2a were investigated by means of the dihedral driver option of the MM3(92) force field. The calculated activation energies of 14.0 and 6.7 kcal mol−1 are in excellent agreement with the experimentally determined value for p-tert-butylcalix[4]arene and the observed flexibility of the exo-calix[4]arene on the NMR timescale.
Spread of the autonomous transposable element hobo in the genome of Drosophila melanogaster.
1995
The transposable element hobo has been introduced into the previously empty Drosophila melanogaster strain Hikone so that its dynamics can be followed and it can be compared with the P element. Five transformed lines were followed over 58 generations. The results were highly dependent on the culture temperature, the spread of hobo element being more efficient at 25 degrees C. The multiplication of hobo sequences resulted in a change in the features of these lines in the hobo system of hybrid dysgenesis. The number of hobo elements remained low (two to seven copies) and the insertions always corresponded to complete sequences. Our findings suggest that, despite their genetic similarities, P …
The last glacial/interglacial record of rodent remains from the Gigny karst sequence in the French Jura used for palaeoclimatic and palaeoecological …
1995
Abstract A multidisciplinary approach has produced an exceptional chronological log of climatic patterns for the Upper Pleistocene sequence of Gigny Cave (Jura, France) covering the Pre-Eemian, Eemian Interglacial, Middle Glacial and Upper Pleniglacial, as well as a part of the Holocene. Multivariate analysis (correspondence and component analysis) of rodent associations from the sequence is used here to characterize the different climatic stages in terms of relative temperature, plant cover and moisture. Faunal analysis establishes: (1) positive and negative correlations among the variations of the different species; (2) the significance of axis 1 (component analysis) which, in terms of te…