Publications by authors named "Casper F"

The estimation of the reliability of magnetic field sensors against failure is a critical point concerning their application for industrial purposes. Due to the physical stochastic nature of the failure events, this can only be done by means of a statistical approach which is extremely time consuming and prevents a continuous observation of the production. Here, we present a novel microstructure design for a parallel measurement of the lifetime characteristics of a sensor population.

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Band Jahn-Teller type structural instabilities of cubic Mn(2)YZ Heusler compounds causing tetragonal distortions can be predicted by ab initio band-structure calculations. This allows for identification of new Heusler materials with tunable magnetic and structural properties that can satisfy the demands for spintronic applications, such as in spin-transfer torque-based devices.

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Heavy stuff: Topological insulators are formed of heavy atoms and host special surface or edge states. The electronic structure is characterized by a Dirac cone within a bulk band gap (see picture) that is generated by strong spin-orbit coupling. A chemist's perspective in terms of bonds, bands, symmetry, and nuclear charge is provided.

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We present a rational design scheme intended to provide stable high spin polarization at the interfaces of the magnetoresistive junctions by fulfilling the criteria of structural and chemical compatibilities at the interface. This can be realized by joining the semiconducting and half-metallic Heusler materials with similar structures. The present first-principles calculations verify that the interface remains half-metallic if the nearest interface layers effectively form a stable Heusler material with the properties intermediately between the surrounding bulk parts.

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In this Letter we show that superconducting Fe(1.01)Se undergoes a structural transition at 90 K from a tetragonal to an orthorhombic phase but that nonsuperconducting Fe(1.03)Se does not.

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The discovery of new high-temperature superconductors based on FeAs has led to a new 'gold rush' in high-T(C) superconductivity. All of the new superconductors share the same common structural motif of FeAs layers and reach T(C) values up to 55 K (ref. 2).

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Introduction: Hereditary gingival fibromatosis (HGF) is a rare condition characterized by progressive enlargement of the gingiva. Most cases follow autosomal dominant genetics, with a reported incidence of 1 in 750,000. In addition to cosmetic concerns, the compromised oral cavity may cause difficulty with eating, speech, hygiene, and oral competence.

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There are many techniques in the treatment of female genital descent. We analysed sacrospinous/sacrotuberal fixation in comparison to abdominal fixation using fascial slings. One of the aims of the study presented was to determine whether there is a differentiation in indications in the use of either technique.

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It has been assumed that low birth weight and high placenta weight were key factors for predicting hypertension in human adulthood. A deficiency in placental 11 beta-HSD-II enzyme activity was supposed to be the underlying cause. To possibly establish 11 beta-HSD-II as a leading factor, we determined 11 beta-HSD-II activities in 133 healthy pregnancies, 21 proteinuric pregnancies complicated by pregnancy-induced hypertension (PIH), 26 non proteinuric PIH pregnancies and 15 pregnancies complicated by fetal growth restriction (32nd-41st gestational week).

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Objective: To investigate the influence of human recombinant follicle-stimulating hormone (FSH) on circulating serum concentrations of the ovarian proteohormones inhibin A, inhibin B, pro alpha-C, and activin A and serum levels of estradiol after down-regulation with GnRH analogue.

Design: Serum concentrations of ovarian proteohormones and estradiol.

Setting: Academic clinical practice.

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The interpretation of cardiotocograms is essentially for perinatal management, it remains labour intensive and depends on training and experience. With the development of modern analysing systems with conventional classification techniques, it seems possible to introduce expert systems and neuronal networks for a better interpretation and classification of cardiotocograms. Techniques of artificial intelligence are powerful tools and should be integrated in future systems.

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Objective: Interest has focused recently on the influences of the polypeptide factors inhibin and activin on the selective regulation of the pituitary secretion of gonadotropins.

Design: Measurement of the concentrations of inhibin-related proteins in relation to the changes in pituitary gonadotropin (FSH, LH) parameters, after GnRH stimulation with a bolus injection of 100 microg gonadorelin, in 19 women with ovulatory disturbances.

Methods: Serum levels of inhibin A and B, activin A, and pro alpha-C were measured using sensitive ELISA kits.

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While computer applications are widely accepted in clinical chemical departments, small numbers of computer systems are used in gynecological endocrinological laboratories. Modern applications should be integrated in local area networks and clinical information systems that improve communication and data exchange within hospitals and the outer resources. Better communication may improve medical quality and will lead to a better therapy for gynecological endocrinological patients.

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Objective: In which way is the biochemical analysis of fine needle biopsy comparable to the biochemical analysis of conventional surgical biopsy samples in the examination of prognosis factors in mammary carcinomas.

Material And Methods: Conventional surgical biopsy and fine needle biopsy were performed on 63 mammary carcinomas. The results from the biochemical analysis of tissue samples, from each form of biopsy, with respect to estradiol and progesterone receptor, UPA and PAI-1, as well as Kathepsin D and the EGF receptor, were compared and statistically analyzed.

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Objective: The purpose of this study was to determine whether the tumor suppressor gene p53 can be used as a prognosis factor to assess individual patient risk in primary ovarian carcinoma.

Materials And Methods: The concentration of the mutated, as well as the wild type p53 was examined in 98 cases of ovarian carcinoma. Among 98 ovarian tumors examined, 77 were primary carcinomas, 14 tumors were metastasis of foreign tumors, and 7 were benign ovarian tumors.

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Unlabelled: Because of ethical constraints upon research during human pregnancy and of the heterogeneity of preeclampsia a number of experimental animal models were used to study pathophysiology of preeclampsia. We reduced the uteroplacental flow by aortic clip technique in 72 SHR-rats in 4 groups (G 1 not gravid--no clip, G 2 not gravid--aortic clip, G 3 gravid--no clip, G 4 gravid--aortic clip). While gravidity normalised blood pressure in SHR (G 3), reduction of the uteroplacental flow significantly increased maternal blood pressure (G1 240/180 mmHG, G2 238/183 mmHg, G3 148/99 mmHG, G4 200/145 mmHg) and leads to significant higher hematocrit, significant lower plasma renin activity and aldosterone plasma concentration, as it is found in human superimposed preeclampsia.

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Objective: The present study was to measure new prognostic factors including the plasminogen activator urokinase and the plasminogen inhibitor PAI-1, as well as p53 and Ki-67, a marker of proliferation and to compare the clinical value of these in relation to the classic histopathological prognostic factors.

Material And Methods: The patient collective included 45 patients with vulvar carcinoma, both primary tumors and recurrences.

Results: Highly significant correlations were found for tumor diameter and thickness.

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Objective: Etiology and pathogenesis of renal changes in pregnancy-induced hypertension (PIH) remain somewhat controversial. Reducing the uterine perfusion leads to the development of systemic hypertension in animal models. Aim of this study was to investigate the effect of systemic hypertension on the kidney during pregnancy.

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Local estrogen substitution has been shown to be more appropriate than any systemic application for the treatment of urogenital symptoms of hormone deficiency. The efficacy, safety and acceptability of a new low-dose drug delivery system consisting of an estradiol-releasing silicone vaginal ring was studied in two multicenter trials. In an open-label comparative trial a total of 219 postmenopausal women were randomized to the estradiol-releasing vaginal ring or to estriol suppositories.

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Objective: To analyze in a retrospective fashion our experiences with obstetrical management following previous incontinence surgery.

Methods: Between 1990 and 1997 4 women presented to our institution in the third trimester of pregnancy with a history of colposuspension performed 3 months to 4 years before onset of pregnancy for second degree stress incontinence. Three of 4 patients experienced recurrent incontinence during the third trimester.

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Unlabelled: Estrogen replacement therapy is used in postmenopausal women with symptoms of urogenital atrophy. The aim of this study was to detect differences in efficacy of a low-dose estradiol-releasing vaginal ring and a placebo ring in the relief of symptoms of estrogen deficiency and reduction of urogenital atrophy (pH and vaginal mucosal maturation) in postmenopausal women.

Design: This was a multicentre double-blind, placebo-controlled study.

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Little is known about the pathophysiological processes leading to superimposed preeclampsia. We present an animal model where the uteroplacental blood flow in spontaneously hypertensive rats (SHR) was reduced by a silver clip. Thus, a superimposed preeclampsia-like syndrome could be studied under defined conditions.

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Pregnancy is accompanied by a physiological activation of intravascular coagulation; however without disorder. Normal markers of coagulation are unchanged despite activation. Special coagulation parameter--such as Thrombin-Antithrombin-III-complex (TAT) or D-Dimer are increased also in normal pregnant women.

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The pathophysiology of preeclampsia has not been fully clarified. A variety of factors have been implicated with this disease including vasoactive peptides and hormones during the last 20 years. Inadequate generation of atrial natriuretic peptide (ANP) has been one of the mechanisms discussed as to possibly contribute to the development of hypertension.

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