GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Document type
Keywords
Publisher
Years
  • 1
    Electronic Resource
    Electronic Resource
    Crystal structure and magnetism of LaCo13−x−yFexSiy compounds (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 80 (1996), S. 336-341 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The crystal structure and magnetic properties of LaCo13−x−yFexSiy compounds were investigated by means of x-ray powder diffraction and magnetization measurements. The substitution of Si for Co induces an order–disorder transition from the cubic NaZn13-type to its tetragonal derivative structure, while the substitution of Fe for Co does not induce such a phase transition. After annealing treatment, the homogeneous range of the cubic phase is narrowed and that of the tetragonal phase is extended. From crystallographic and thermodynamic points of view, the sta- bility of the cubic and the tetragonal phases is discussed. The measured magnetic moment of LaCo13−x−yFexSiy coincides well with the theoretical prediction based on the magnetic valence model. Within the framework of this model, LaCo13−x−yFexSiy compounds can be considered as strong ferromagnets and their magnetic moment can be theoretically predicted. The composition dependence of Curie temperature is discussed within the mean field approximation. At higher iron concentration the decrease of Curie temperature with Fe concentration might be attributed to the increase of the number of antiferromagnetically coupled Fe–Fe pairs and the decrease of the ferromagnetic coupling between transition metal atoms. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.362786
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Metalliclike mictomagnetic state in La0.55R0.15Ca0.3MnO3 (R=Y and Ho) (1998)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 84 (1998), S. 651-653 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetic and electronic transport properties of the title compounds are systematically studied. Both compounds are found to have similar properties. The magnetic measurements are consistent with the mictomagnetic behavior. An insulator-to-metal transition is observed with decreasing temperature and the low temperature resistivity shows the metalliclike feature. It is proposed that apart from the already identified ferromagnetic metal and spin glass insulator phases, the metalliclike mictomagnetic phase should exist at the boundary area between the two known phases in the universal phase diagram for the manganates. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.368067
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Crystal structure and magnetic properties of LaCo13−xSix compounds (1994)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 64 (1994), S. 1650-1652 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Tetragonal LaCo13−xSix compounds have been obtained by annealing cubic LaCo13−xSix compounds. The space group for the tetragonal structure is I4/mcm. Atomic ordering occurs in the tetragonal LaCo13−xSix compounds, i.e., Si atoms show a strong preference for occupying a specific crystallographic position. The tetragonal LaCo13−xSix compounds are ferromagnetic with Curie temperatures higher than 900 K. The magnetic moment per Co atom in the tetragonal LaCo13−xSix compounds decreases with Si content, which can be explained by the rigid-band model. The tetragonal LaCo13−xSix compounds are expected to be promising candidates for permanent magnets purpose.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.111820
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    High-Tc ramp-type Josephson junctions with a continually graded Y1−xPrxBa2Cu3Oy barrier (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 79 (2001), S. 3101-3103 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: High-Tc Josephson junctions with a graded barrier have been prepared by using a composite target. Such a barrier is synthesized by utilizing Y1−xPrxBa2Cu3Oy with a continually graded concentration of Pr, in which no lattice mismatch and other incompatible problems take place. The structural interfaces are absent in the weak link region and Josephson coupling occurs at the naturally formed superconducting/normal interfaces within the Y1−xPrxBa2Cu3Oy layer. Thus, it can significantly enhance the reproducibilty and performance of these junctions. The temperature dependences of the barrier thickness and Josephson were also studied.© 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1414295
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Superconductivity of YBa2−x Nd x Cu3O y Solid Solution (1998)
    Springer
    Journal of superconductivity 11 (1998), S. 221-223 
    Details
    ISSN: 1572-9605
    Keywords: YBa2−x Nd x Cu3O y ; X-ray diffraction ; resistivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract The solubility of Nd at the Ba sites and the superconductivity of YBa2−x Nd x Cu3O y were investigated by X-ray powder diffraction and measurements of the electrical resistance and ac susceptibility. The single Re123 phase was obtained for x≤0.30. The onset transition temperature $$T_{\text{c}}^{{\text{on}}}$$ is insensitive to the Nd content x in the region of x≤0.40. All are higher than 95 K. The zero resistance transition temperatures $$T_{\text{c}}^{{\text{zero}}}$$ , however, exhibits two-step variation with the increase of x. For x≤0.25, $$T_{\text{c}}^{{\text{zero}}}$$ are all above 92 K. The highest $$T_{\text{c}}^{{\text{zero}}}$$ of 94 K was obtained for x=0.25. For x≥0.3 $$T_{\text{c}}^{{\text{zero}}}$$ drops sharply to about 84 K. Finally $$T_{\text{c}}^{{\text{zero}}}$$ falls to 30 K and $$T_{\text{c}}^{{\text{zero}}}$$ is below 10 K for x=0.5. The two-step variation of T c might be an indication of the existence of two trap levels for holes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022619531110
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    facet.materialart.
    Unknown
    Association of a Genetic Risk Score With Prevalent and Incident Myocardial Infarction in Subjects Undergoing Coronary Angiography [Original Articles] (2012)
    American Heart Association (AHA)
    Details
    Publication Date: 2012-08-15
    Description: Background— Genome-wide association studies have identified multiple variants associating with coronary artery disease (CAD) and myocardial infarction (MI). Whether a combined genetic risk score (GRS) is associated with prevalent and incident MI in high-risk subjects remains to be established. Methods and Results— In subjects undergoing cardiac catheterization (n=2597), we identified cases with a history of MI onset at age 〈70 years and controls ≥70 years without prior MI and followed them for incident MI and death. Genotyping was performed for 11 established CAD/MI variants, and a GRS was calculated based on average number of risk alleles carried at each locus weighted by effect size. Replication of association findings was sought in an independent angiographic cohort (n=2702). The GRS was significantly associated with prevalent MI, occurring before age 70, compared with older controls (≥70 years of age) with no history of MI ( P 〈0.001). This association was successfully replicated in a second cohort, yielding a pooled P value of 〈0.001. The GRS modestly improved the area-under–the–curve statistic in models of prevalent MI with traditional risk factors; however, the association was not statistically significant when elderly controls without MI but with s\ angiographic CAD were examined (pooled P =0.11). Finally, during a median 2.5-year follow-up, only a nonsignificant trend was noted between the GRS and incident events, which was also not significant in the replication cohort. Conclusions— A GRS of 11 CAD/MI variants is associated with prevalent MI but not near-term incident adverse events in 2 independent angiographic cohorts. These findings have implications for understanding the clinical use of genetic risk scores for secondary as opposed to primary risk prediction.
    Keywords: Risk Factors, Genomics, Acute coronary syndromes, Acute myocardial infarction, Epidemiology, Genetics of cardiovascular disease
    Print ISSN: 1942-325X
    Electronic ISSN: 1942-3268
    Topics: Medicine
    Published by American Heart Association (AHA)
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Paradoxical Association of Enhanced Cholesterol Efflux With Increased Incident Cardiovascular Risks [Clinical and Population Studies] (2013)
    American Heart Association (AHA)
    Details
    Publication Date: 2013-06-14
    Description: Objective— Diminished cholesterol efflux activity of apolipoprotein B (apoB)–depleted serum is associated with prevalent coronary artery disease, but its prognostic value for incident cardiovascular events is unclear. We investigated the relationship of cholesterol efflux activity with both prevalent coronary artery disease and incident development of major adverse cardiovascular events (death, myocardial infarction, or stroke). Approach and Results— Cholesterol efflux activity from free cholesterol–enriched macrophages was measured in 2 case–control cohorts: (1) an angiographic cohort (n=1150) comprising stable subjects undergoing elective diagnostic coronary angiography and (2) an outpatient cohort (n=577). Analysis of media from cholesterol efflux assays revealed that the high-density lipoprotein fraction (1.063〈 d 〈1.21) contained only a minority (40%) of [ 14 C]cholesterol released, with the majority found within the lipoprotein particle–depleted fraction, where 60% was recovered after apolipoprotein A1 immunoprecipitation. Albumin immunoprecipitation recovered another 30% of radiolabeled cholesterol within this fraction. Enhanced cholesterol efflux activity from ATP-binding cassette transporter A1–stimulated macrophages was associated with reduced risk of prevalent coronary artery disease in unadjusted models within both cohorts; however, the inverse risk relationship remained significant after adjustment for traditional coronary artery disease risk factors only within the outpatient cohort. Surprisingly, higher cholesterol efflux activity was associated with increase in prospective (3 years) risk of myocardial infarction/stroke (adjusted hazard ratio, 2.19; 95% confidence interval, 1.02–4.74) and major adverse cardiovascular events (adjusted hazard ratio, 1.85; 95% confidence interval, 1.11–3.06). Conclusions— Heightened cholesterol efflux to apoB-depleted serum was paradoxically associated with increased prospective risk for myocardial infarction, stroke, and death. The majority of released radiolabeled cholesterol from macrophages in cholesterol efflux activity assays does not reside within a high-density lipoprotein particle.
    Print ISSN: 1079-5642
    Electronic ISSN: 1524-4636
    Topics: Medicine
    Published by American Heart Association (AHA)
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    Plasma Aspirin Hydrolysis Variation [Enzymology] (2013)
    The American Society for Biochemistry and Molecular Biology (ASBMB)
    Details
    Publication Date: 2013-04-27
    Description: Aspirin is rapidly hydrolyzed within erythrocytes by a heterodimer of PAFAH1b2/PAFAH1b3 but also in plasma by an unidentified activity. Hydrolysis in both compartments was variable, with a 12-fold variation in plasma among 2226 Cleveland Clinic GeneBank patients. Platelet inhibition by aspirin was suppressed in plasma that rapidly hydrolyzed aspirin. Plasma aspirin hydrolysis was significantly higher in patients with coronary artery disease compared with control subjects (16.5 ± 4.4 versus 15.1 ± 3.7 nmol/ml/min; p = 3.4 × 10−8). A genome-wide association study of 2054 GeneBank subjects identified a single locus immediately adjacent to the BCHE (butyrylcholinesterase) gene associated with plasma aspirin hydrolytic activity (lead SNP, rs6445035; p = 9.1 × 10−17). However, its penetrance was low, and plasma from an individual with an inactivating mutation in BCHE still effectively hydrolyzed aspirin. A second aspirin hydrolase was identified in plasma, the purification of which showed it to be homomeric PAFAH1b2. This is distinct from the erythrocyte PAFAH1b2/PAFAH1b3 heterodimer. Inhibitors showed that both butyrylcholinesterase (BChE) and PAFAH1b2 contribute to aspirin hydrolysis in plasma, with variation primarily reflecting non-genetic variation of BChE activity. Therefore, aspirin is hydrolyzed in plasma by two enzymes, BChE and a new extracellular form of platelet-activating factor acetylhydrolase, PAFAH1b2. Hydrolytic effectiveness varies widely primarily from non-genetic variation of BChE activity that affects aspirin bioavailability in blood and the ability of aspirin to inhibit platelet aggregation.
    Print ISSN: 0021-9258
    Electronic ISSN: 1083-351X
    Topics: Biology , Chemistry and Pharmacology
    Published by The American Society for Biochemistry and Molecular Biology (ASBMB)
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    Diminished Antioxidant Activity of High-Density Lipoprotein-Associated Proteins in Chronic Kidney Disease [Coronary Heart Disease] (2013)
    American Heart Association (AHA)
    Details
    Publication Date: 2013-04-25
    Description: Background Decreased serum arylesterase activity, catalyzed by the high-density lipoprotein–associated paraoxonase (PON)-1, is associated with increased oxidant stress and atherosclerosis risk. We sought to determine the prognostic value of serum PON-1 activity, as monitored by PON or arylesterase activities, in subjects with chronic kidney disease (CKD), particularly in relation to established cardiac biomarkers. Methods and Results Serum arylesterase and PON activities were measured in sequential subjects with CKD (n=630; estimated glomerular filtration rate [eGFR] 〈60 mL/min per 1.73 m 2 ) and an age- and sex-matched control group of non-CKD subjects (n=315) presenting for cardiac evaluations and prospectively followed for incident (3-year) major adverse cardiac events (composite of death, nonfatal myocardial infarction, and stroke). Serum arylesterase activity in CKD subjects was lower compared with that in non-CKD control subjects [median (interquartile range) 94 (77 to 112) versus 103 (85 to 121) μmol(L·min) per mL, P 〈0.001]; similarly, PON activity in CKD subjects was lower compared with that in non-CKD control subjects [median (interquartile range) 474 (275 to 936) versus 586 (301 to 1118) nmol(L·min) per mL, P 〈0.001]. Lower serum arylesterase (hazard ratio 1.8, 95% CI 1.26 to 2.57, P 〈0.01) was a predictor of poorer outcomes. After adjusting for traditional risk factors and medication use, lower serum arylesterase (hazard ratio 1.55, 95% CI 1.08 to 2.23, P 〈0.05) still conferred an increased risk of major adverse cardiac events at 3 years. Conclusions In patients with CKD, decreased serum arylesterase activity, a measure of diminished antioxidant properties of PON-1, predicts higher risk of incident long-term adverse cardiovascular events (heart attack, stroke, or death) in multivariable models adjusting for established clinical and biochemical risk factors.
    Electronic ISSN: 2047-9980
    Topics: Medicine
    Published by American Heart Association (AHA)
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Genome-wide and gene-centric analyses of circulating myeloperoxidase levels in the charge and care consortia (2013)
    Oxford University Press
    Details
    Publication Date: 2013-07-26
    Description: Increased systemic levels of myeloperoxidase (MPO) are associated with the risk of coronary artery disease (CAD). To identify the genetic factors that are associated with circulating MPO levels, we carried out a genome-wide association study (GWAS) and a gene-centric analysis in subjects of European ancestry and African Americans (AAs). A locus on chromosome 1q31.1 containing the complement factor H ( CFH ) gene was strongly associated with serum MPO levels in 9305 subjects of European ancestry (lead SNP rs800292; P = 4.89 x 10 –41 ) and in 1690 AA subjects (rs505102; P = 1.05 x 10 –8 ). Gene-centric analyses in 8335 subjects of European ancestry additionally identified two rare MPO coding sequence variants that were associated with serum MPO levels (rs28730837, P = 5.21 x 10 –12 ; rs35897051, P = 3.32 x 10 –8 ). A GWAS for plasma MPO levels in 9260 European ancestry subjects identified a chromosome 17q22 region near MPO that was significantly associated (lead SNP rs6503905; P = 2.94 x 10 –12 ), but the CFH locus did not exhibit evidence of association with plasma MPO levels. Functional analyses revealed that rs800292 was associated with levels of complement proteins in serum. Variants at chromosome 17q22 also had pleiotropic cis effects on gene expression. In a case–control analysis of ~80 000 subjects from CARDIoGRAM, none of the identified single-nucleotide polymorphisms (SNPs) were associated with CAD. These results suggest that distinct genetic factors regulate serum and plasma MPO levels, which may have relevance for various acute and chronic inflammatory disorders. The clinical implications for CAD and a better understanding of the functional basis for the association of CFH and MPO variants with circulating MPO levels require further study.
    Print ISSN: 0964-6906
    Electronic ISSN: 1460-2083
    Topics: Biology , Medicine
    Published by Oxford University Press
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...