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M Neuhaus

Publications and source records attributed to M Neuhaus.

8 recordsLinked to original sources
PubMed2006

Commensurability effects in superconducting Nb films with quasiperiodic pinning arrays.

We study experimentally the critical depinning current I(c) versus applied magnetic field B in Nb thin films which contain 2D arrays of circular antidots placed on the nodes of quasiperiodic (QP) fivefold Penrose lattices. Close to the transition temperature T(c) we observe matching of the vortex lattice with the QP pinning array, confirming essential features in the I(c)(B) patterns as predicted by Misko et al. [Phys. Rev. Lett. 95, 177007 (2005)]. We find a significant enhancement in I(c)(B) for QP pinning arrays in comparison to I(c) in samples with randomly distributed antidots or no antidots.

Journal Article↗
PubMed2005

High-efficiency deterministic Josephson vortex ratchet.

We investigate experimentally a Josephson vortex ratchet--a fluxon in an asymmetric periodic potential driven by a deterministic force with zero time average. The highly asymmetric periodic potential is created in an underdamped annular long Josephson junction by means of a current injector providing an efficiency of the device up to 91%. We measured the ratchet effect for driving forces with different spectral content. For monochromatic high-frequency drive the rectified voltage becomes quantized. At high driving frequencies we also observe chaos, subharmonic dynamics, and voltage reversal due to the inertial mass of a fluxon.

Journal Article↗
PubMed2001

Diagnostic value of immunohistochemically detected surfactant--apoprotein-A in malignant tumors located in the lungs: report of two cases.

We report two cases of patients suffering from multiple tumors in the lungs with questionable origin. In these cases, the expression of Surfactant-apoprotein-A (SP-A) by the tumor cells has been a helpful feature in the process of diagnosis by indicating primary carcinomas of the lungs. Surfactant-apoprotein-A is expressed by the pneumocytes II in lung tissue and a portion of non-small cell lung carcinomas and has not yet been found to be expressed by other tumors when detected immunohistochemically by use of the monoclonal antibody PE-10. We analyzed formalin-fixed, paraffin-embedded specimens of different malignancies with pulmonary location for the expression of SP-A by the use of PE-10 with other antibodies against additional epitopes such as the thyroid transcription factor-1. In normal lung areas a distinct staining of the pneumocytes II has been observed. All the control sections of primary and metastatic nonlung-carcinoma specimen in our study remained negative. The monoclonal antibody PE-10 used in this study provides high specificity when compared to the results obtained with polyclonal antibodies. One of the two cases reported, a mucinous carcinoma of the lungs, had been negative for thyroid transcription factor-1 but positive for SP-A. Thus, SP-A detected by immunohistochemistry using the monoclonal antibody PE-10, together with other parameters such as thyroid transcription factor-1, may be a useful tool for individual diagnosis of malignomas located in the lungs with a questionable primary origin. Ann Diagn Pathol 5:84-90, 2001.

Adenocarcinoma, Mucinous↗
PubMed1999

Polysomies but not Y chromosome losses have prognostic significance in pTa/pT1 urinary bladder cancer.

A disturbed cellular DNA content is of potential diagnostic and prognostic relevance in urinary bladder cancer. To evaluate the prognostic significance of individual chromosomal aberrations in superficial bladder cancer, specimens of 105 tumors (67 pTa, 38 pT1) were examined by fluorescence in situ hybridization (FISH). FISH allows quantitation of chromosomes on a cell by cell level. Centromere probes for the chromosomes Y, 1, and 17 were used. There was a strong association between polysomies of the chromosomes 1 (found in 46% of tumors) and 17 (40% of tumors, P < .0001). Polysomies (1 and 17) were significantly more frequent in pT1 than in pTa tumors (P < .0001 each). In pTa tumors, polysomies of both chromosomes were linked to a high risk of recurrences; polysomy 17 was associated with an increased risk of progression (P < .05 each). There was no significant association between polysomies and an unfavorable prognosis in pT1 carcinomas. Previous studies had suggested a prognostic role of Y losses in bladder cancer. However, Y losses were not linked to recurrences or tumor progression in pTa or pT1 tumors of 67 male patients. These data show that marked genetic differences exist between pTa and pT1 carcinomas. They also indicate that polysomies of different chromosomes may have prognostic relevance in pTa urinary bladder cancer.

Adult↗
PubMed1982

Bulimia nervosa: sex role attitude, sex role behavior, and sex role related locus of control in bulimarexic women.

Thirty-four women with bulimia nervosa and 34 women without bulimarexic symptoms (but matched for age, weight, deviance from ideal weight, and educational status) were compared as to how liberated their attitude towards the woman's role in society (= their sex role attitude, SRA) and their actual own behavior as females (= their sex role behavior, SRB) were. The degree to which their general attitude towards sex role and their own sex role behavior differed from each other was also investigated. Experimental and control group were also compared concerning their sex role related locus of control (SRLC). SRA and SRB were significantly less liberated in the bulimarexic group than in the control group. In addition, the bulimarexic group showed a wide gap between their general attitude (SRA) and actual behavior (SRB) as to the degree of liberation. No such discrepancy was found in the control subjects. The sex related locus of control data showed that bulimarexic women had significantly higher external and fatalistic control, and lower internal control than the comparison subjects.

Adult↗