Effect of Bi and Sr concentrations on the formation of the 2223 phase in Bi-Pb-Sb-Sr-Ca-Cu-O materials, obtained under different conditions of thermal treatment

The superconducting properties and the phase and chemical composition of Bi _x Pb_0.3Sb_0.1Sr _y Ca₂Cu₃O_z (x=1.5, 1.6, and 1.7;y=1.9, 2.0, and 2.1) materials synthesized by one-step and multistep thermal treatments have been investigated. The multistep annealing between 825–875°C promotes the 2223 phase. The change of Bi concentration has little effect on the 2223 phase formation, regardless of the kind of thermal treatment used, but increasing the Sr concentration (y> 2) strongly inhibits this phase. It has also been established that the loss of Pb after synthesis depends on the initial Bi concentration. The loss of Pb decreases when the initial Bi content is lower.     

Postoperative analgesia. Simple methods for improvements exist

An improved, combined staining method for myofibrillar ATPase (m-ATPase) and for acetylcholinesterase activity is described. This method allows the observations, on the same slide, of the classical histochemical m-ATPase profile following the Brooke and Kaiser technique and the neuromuscular junction morphology. Thus the pattern of innervation, nerve ending structure and number of nerve endings along the fibres is shown simultaneously for the basic differentiation between slow and fast fibres. The use of acidic and alkaline preincubation allows better visualization of endplate morphology and avoids the masking effect of a positive m-ATPase reaction. The technique has been validated on skeletal muscles from avian and mammalian species.     

Elbow flexion strength curves in untrained men and women and male bodybuilders

The mechanical response of intervertebral joints is deeply influenced by disc degeneration. The phenomenon is expressed in terms of variations in the biomechanical properties of the material, whose compressibility characteristics change because of the liquid content loss in the tissue and, what is even more important, to prolapse. In this work, the problem is investigated by means of a computational mechanics approach; a coupled material and geometric non-linear model is developed, representing vertebra, annulus and nucleus submitted to an axial load. A transversely isotropic law is assumed for cortical bone in the vertebral body and an isotropic law for the cancellous portion; a hyperelastic formulation is assumed for the disc, allowing effective interpretation of the mechanical characteristics of degeneration. The results obtained are reported with regard to bony endplate and annulus behaviour; interaction phenomena between bony endplate and nucleus are emphasized.     

Assessing multidisciplinary areas of science and technology: A synthetic bibliometric study of Dutch nuclear energy research

This paper presents a selection of results of a comprehensive quantitative, research literature-based study of Dutch energy research. The primary goal of this paper is to provide an overview of what bibliometric data from ISI and non-ISI databases may offer to describe the state of affairs in a scientific field. It illustrates the added value of combining bibliometric indicators of publication output, international visibility, international co-operation, and interdisciplinarity in a study of nuclear energy research in the 1980's when its budget decreased dramatically.     

Surgical management of congenital high vaginal atresia

In the past 15 years five neonates and children have been treated for high vaginal atresia at the Surgical Unit of Department of Pediatrics, University Medical School, Pécs, Hungary. In three of the six patients distal atresia of the vagina was found (Type III). Two of the three were neonates and had a large hydrometrocolpos and the third, a 13-year-old girl, hematometrocolpos. In the fourth patient the vaginal atresia was associated with cloacal and anorectal malformation (Type V). In the fifth there was a duplication of uterus and vagina; however, only one of the two vaginas was atretic. In three patients a pull-through of the vagina was carried out, in one of them according to Pena, in another a transvesical approach, as suggested by Monfort, was used. Following repeated surgeries in the patient with cloacal malformation the vagina was replaced with large intestine. In the case of duplication of vagina and uterus one half of the duplication was removed.     

Relative sedimentation of hematopoietic progenitors in human cord blood, peripheral blood, and bone marrow as determined by counterflow centrifugal elutriation

OBJECTIVE: Although there have been many studies of the outcome of anorexia nervosa, methodological weaknesses limit their interpretation. The authors used a case-control design to try to improve knowledge about the outcome of anorexia nervosa. METHOD: All new female patients referred to an eating disorders service between Jan. 1, 1981, and Dec. 31, 1984, who had probable or definite anorexia nervosa were eligible for inclusion. Of these women, 86.4% (N = 70) were located and agreed to participate. The comparison group (N = 98) was a random community sample. All subjects were interviewed with a structured diagnostic instrument. RESULTS: A minority of the patients (10%) continued to meet the criteria for anorexia nervosa a mean of 12 years after initial referral. Even among those who no longer met these criteria, relatively low body weight and cognitive features characteristic of anorexia nervosa (perfectionism and cognitive restraint) persisted. The rates of lifetime comorbid major depression, alcohol dependence, and a number of anxiety disorders were very high. CONCLUSIONS: In the managed care/brief treatment era, therapeutic approaches with an excessive focus on weight gain that neglect the detection and treatment of associated psychological features and comorbidity may be inappropriate. Anorexia nervosa is a serious psychiatric disorder with substantial morbidity.     

Chromosomal and genomic organization of Ty1-copia-like retrotransposon sequences in the genus Avena

Regulation of ligand-mediated signal transduction through transmembrane tyrosine kinase growth factor receptors involves phosphorylation of tyrosine residues in the intracellular domain of the receptor. The insulin-like growth factor-I (IGF-I) receptor contains three tyrosine residues in the carboxy-terminal domain at positions 1250, 1251, and 1316. Of these, only the tyrosine at position 1316 is conserved in the homologous position of the insulin receptor. Mutational analysis was used to study the role of these tyrosines in specific outcomes of IGF-I-mediated signal transduction. Mutations in the human IGF-I receptor were either replacement of tyrosines 1250 and 1251 with phenylalanine and histidine (yyFH), respectively, or replacement of the conserved distal tyrosine (position 1316) with phenylalanine (yCF). The yyFH mutation results in an IGF-I receptor with the amino acids found in the homologous position of the human insulin receptor. Cells overexpressing mutated IGF-I receptors were compared with cells expressing only endogenous IGF-I receptors or overexpressing wild-type IGF-I receptors. The ability of yyFH mutant IGF-I receptors to autophosphorylate the beta-subunit or phosphorylate insulin receptor substrate-1 was not significantly different from wild-type type IGF-I receptors. However, one or both of the proximal tyrosine residues (positions 1250 and 1251) in the carboxy-terminus of the IGF-I receptor are essential for IGF-I-stimulation of mitogenic and tumorigenic pathways. IGF-I-induced mitogenesis, measured as thymidine incorporation and cellular proliferation, was abrogated in cells overexpressing mutant IGF-I receptors with replacement of the proximal double tyrosines (positions 1250 and 1251). Fibroblasts expressing this mutant IGF-I receptor formed fewer tumors than the negative control cells, whereas cells expressing wild-type IGF-I receptors formed large tumors in all recipient mice injected. Conversely, cells expressing mutant IGF-I receptors with only the conserved distal tyrosine (position 1316) replaced had slightly reduced IGF-I-stimulated beta-subunit autophosphorylation, thymidine incorporation, and cellular proliferation when compared with cells expressing wild-type receptors. Phosphorylation of insulin receptor substrate-1 by the yCF mutant receptors was not impaired. Despite the ability of these mutant receptors to stimulate mitogenic growth, fibroblasts expressing this mutant receptor were also incapable of forming tumors in recipient nude mice. The distal tyrosine (position 1316) of the IGF-I receptor is crucial for tumor formation but is not essential for IGF-I stimulated mitogenesis. Thus, the tyrosine moieties in the carboxy-terminus of the IGF-I receptor participate in the signal transduction pathways that affect the mitogenic and tumorigenic potentials of cells expressing mutant IGF-I receptors.