234 research outputs found

    Impact of comorbidity indexes on non-relapse mortality.

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    Comorbidity indexes (CI) have been reported to predict non-relapse mortality (NRM) and overall survival after allogeneic hematopoietic stem cell transplantation (HSCT) (Charlson's comorbidity index (CCI), hematopoietic cell transplantation CI (HCT-CI) and the pre-transplantation assessment of mortality (PAM) score). Which of these indexes best predict survival is unknown yet. We retrospectively studied 286 patients who underwent allogeneic HSCT. HCT-CI and PAM scores required grading according to pre-transplant pulmonary function tests (PFTs), which were lacking for some patients. We thus designed a reduced HCT-CI and an adjusted PAM, without results of PFTs. Using CCI, 25% of patients had indexes of 1 or more; median reduced HCT-CI score was 1; median adjusted PAM score was 24. The discriminative properties of the three CIs were rather low in our population. Comparison of patients and transplant characteristics between our and Seattle group's cohorts, however, revealed significant differences in more children, in more cord blood HSCT and in HSCT for Fanconi anemia in St Louis. Finally, multivariate analysis of scoring items revealed that age, matched unrelated or mismatched donor and hepatic disease were associated with NRM in our cohort. Translating use for patient's counseling or decision to proceed to transplant of these CIs will need prospective studies in a large independent cohort

    Experimental Setups for Single Event Effect Studies

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    Experimental setups are being prepared to test and to qualify electronic devices regarding their tolerance to Single Event Effect (SEE). A multiple test setup and a new beam line developed especially for SEE studies at the São Paulo 8 UD Pelletron accelerator were prepared. This accelerator produces proton beams and heavy ion beams up to 107Ag. A Super conducting Linear accelerator, which is under construction, may fulfill all of the European Space Agency requirements to qualify electronic components for SEE

    Correlations of structural, magnetic, and dielectric properties of undoped and doped CaCu3Ti4O12

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    The present work reports synthesis, as well as a detailed and careful characterization of structural, magnetic, and dielectric properties of differently tempered undoped and doped CaCu3Ti4O12 (CCTO) ceramics. For this purpose, neutron and x-ray powder diffraction, SQUID measurements, and dielectric spectroscopy have been performed. Mn-, Fe-, and Ni-doped CCTO ceramics were investigated in great detail to document the influence of low-level doping with 3d metals on the antiferromagnetic structure and dielectric properties. In the light of possible magnetoelectric coupling in these doped ceramics, the dielectric measurements were also carried out in external magnetic fields up to 7 T, showing a minor but significant dependence of the dielectric constant on the applied magnetic field. Undoped CCTO is well-known for its colossal dielectric constant in a broad frequency and temperature range. With the present extended characterization of doped as well as undoped CCTO, we want to address the question why doping with only 1% Mn or 0.5% Fe decreases the room-temperature dielectric constant of CCTO by a factor of ~100 with a concomitant reduction of the conductivity, whereas 0.5% Ni doping changes the dielectric properties only slightly. In addition, diffraction experiments and magnetic investigations were undertaken to check for possible correlations of the magnitude of the colossal dielectric constants with structural details or with magnetic properties like the magnetic ordering, the Curie-Weiss temperatures, or the paramagnetic moment. It is revealed, that while the magnetic ordering temperature and the effective moment of all investigated CCTO ceramics are rather similar, there is a dramatic influence of doping and tempering time on the Curie-Weiss constant.Comment: 10 pages, 11 figure

    The origin of the dual ferroic properties in quasi-centrosymmetrical SrFe12−xInxO19 hexaferrites

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    The local crystal/magnetic structures of the SrFe12−xInxO19 solid solutions (x = 0.1; 0.3; 0.6 and 1.2) were investigated using neutron powder diffraction. The measurements of the electric polarization for all investigated samples were carried out as a function of the external electric field. The presence of the ferroelectric and ferromagnetic ordering (dual ferroic ordering) in the SrFe12−xInxO19 hexaferrites at 300 K was found. This appearance contradicts to the conventional opinion describing their crystal structure (centrosymmetric space group P63/mmc (No. 194)). The reason for the existence of a spontaneous polarization (nonzero dipole moment) in the SrFe12−xInxO19 hexaferrites continues controversial. The crystal structure of the hexaferrites was considered both the centrosymmetric P63/mmc and non-centrosymmetric P63mc space groups. This fact made it possible to find a connection between the emerging dipole moment and not equal distortions of the neighbor oxygen polyhedral. The nature description of the nonzero dipole moment formation in a quasi-centrosymmetrical system of the In-substituted SrFe12−xInxO19 hexaferrites was presented based on the neutron diffraction data.This work was supported by the Russian Science Foundation (Agreement no. 19-19-00694 of 06 May 2019).With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).Peer reviewe

    Affective economies, pandas, and the atmospheric politics of lively capital

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    This paper is concerned with the affective economies of lively capital. Its central argument is that nonhuman life itself has become a locus of accumulation, marked by an atmospheric politics of capital: the intensification of relations between life and productivity by incorporating entire lifeworlds into regimes of generating value. Focusing on the Giant panda – a spectacular icon raising millions of dollars globally – the paper first examines junctures at which their charismatic affects emerge and are manipulated to produce value. Turning to panda lifeworlds in zoos, it then shows how such value production is contingent upon affective labours nonhumans perform in captivity. Nonhuman labour, as a component of atmospheric politics, enables understanding how lively capital is produced and reproduced, a theme interrogated through a critical analysis of the commercial global circulation of pandas. The paper develops the concept of atmospheric politics – an intervention in an animal’s milieu and its affective intensities – as a means for analyzing the dynamics of lively capital. Atmospheric politics retrieves a critical political economy obscured by the concept of nonhuman charisma, and restages biopower as an apparatus and political technology of capital.Parts of the research conducted for this paper was enabled by a British Academy Postdoctoral Fellowship (Award No. pf140038)

    Ovarian-Adnexal Reporting Data System Magnetic Resonance Imaging (O-RADS MRI) score for risk stratification of sonographically indeterminate adnexal masses.

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    Importance: Approximately one-quarter of adnexal masses detected at ultrasonography are indeterminate for benignity or malignancy, posing a substantial clinical dilemma. Objective: To validate the accuracy of a 5-point Ovarian-Adnexal Reporting Data System Magnetic Resonance Imaging (O-RADS MRI) score for risk stratification of adnexal masses. Design, Setting, and Participants: This multicenter cohort study was conducted between March 1, 2013, and March 31, 2016. Among patients undergoing expectant management, 2-year follow-up data were completed by March 31, 2018. A routine pelvic MRI was performed among consecutive patients referred to characterize a sonographically indeterminate adnexal mass according to routine diagnostic practice at 15 referral centers. The MRI score was prospectively applied by 2 onsite readers and by 1 reader masked to clinical and ultrasonographic data. Data analysis was conducted between April and November 2018. Main Outcomes and Measures: The primary end point was the joint analysis of true-negative and false-negative rates according to the MRI score compared with the reference standard (ie, histology or 2-year follow-up). Results: A total of 1340 women (mean [range] age, 49 [18-96] years) were enrolled. Of 1194 evaluable women, 1130 (94.6%) had a pelvic mass on MRI with a reference standard (surgery, 768 [67.9%]; 2-year follow-up, 362 [32.1%]). A total of 203 patients (18.0%) had at least 1 malignant adnexal or nonadnexal pelvic mass. No invasive cancer was assigned a score of 2. Positive likelihood ratios were 0.01 for score 2, 0.27 for score 3, 4.42 for score 4, and 38.81 for score 5. Area under the receiver operating characteristic curve was 0.961 (95% CI, 0.948-0.971) among experienced readers, with a sensitivity of 0.93 (95% CI, 0.89-0.96; 189 of 203 patients) and a specificity of 0.91 (95% CI, 0.89-0.93; 848 of 927 patients). There was good interrater agreement among both experienced and junior readers (κ = 0.784; 95% CI, 0.743-0824). Of 580 of 1130 women (51.3%) with a mass on MRI and no specific gynecological symptoms, 362 (62.4%) underwent surgery. Of them, 244 (67.4%) had benign lesions and a score of 3 or less. The MRI score correctly reclassified the mass origin as nonadnexal with a sensitivity of 0.99 (95% CI, 0.98-0.99; 1360 of 1372 patients) and a specificity of 0.78 (95% CI, 0.71-0.85; 102 of 130 patients). Conclusions and Relevance: In this study, the O-RADS MRI score was accurate when stratifying the risk of malignancy in adnexal masses

    Manifold of spin states and dynamical temperature effects in LaCoO3: Experimental and theoretical insights

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    The unconventional transport and magnetic properties of perovskitelike lanthanum cobalt oxide LaCoO3 have been studied for more than five decades. This highly correlated electron system exhibits a variety of peculiar properties that are desirable for environmentally friendly energy solutions, fuel cell technologies, novel diesel engines, and oxyfuel power plants. However, the true spin state of the Co3+ ion is an important but still unresolved issue that underlies these applications. Although many theoretical models have been proposed, finding supporting experimental evidence of spin-state transitions is extremely difficult. Not until recently have new advanced scattering methods emerged allowing unprecedented precision in determining the crystal structure of LaCoO3. In this work, we combine high-resolution extended x-ray absorption fine structure, x-ray powder diffraction, and neutron powder and single-crystal diffraction over a broad range of temperatures, from 2 up to 1000 K, as well as quantum mechanical modeling to study the spin-state transition in LaCoO3 and in a reference sample of LaGaO3. Our results suggest that the Co ions are mainly in a low-spin state at temperatures below 150 K, with a minority of ions in a high-spin state. With an increase in the temperature the gradual transition from low- to intermediate-spin state occurs up until 550 K. At the metal-insulator transition at 550 K, the long-range domains of the intermediate-spin states become a dominant contribution. Above 550 K, a transition from intermediate- to high-spin state is observed. It is established that a slight change in the degree of pd hybridization can lead to the appearance of a spin-state transition which might be induced by both temperature and surface effects in powder crystallites. © 2019 American Physical Society.U.S. Department of Energy, USDOERussian Foundation for Basic Research, RFBR: 17-302-50018-molnrOffice of Science, SCThe authors are indebted to V. Efimov for stimulating discussions, to D. Chernyshov (ESRF) for his help with diffraction experiments and data analysis, and to A. Kuzmin for software creation to calculate U ⊥ and U | | from the anisotropic ADP. The results of the theoretical part of the work including DFT + DMFT calculations were obtained within the state assignment of Minobrnauki of Russia (topic Electron No. AAAA-A18-118020190098-5). Calculations were performed using the Supercomputing Center of IMM UrB RAS. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. This work was based on experiments performed at the Swiss spallation neutron source SINQ, Paul Scherrer Institute, Villigen. The reported study was funded by the RFBR within research Project No. 17-302-50018-molnr. The EXAFS experiments were performed on beamline BM29 at the European Synchrotron Radiation Facility (ESRF), Grenoble, France

    Features of Structure, Magnetic Sstate and Electrodynamic Performance of SrFe12−xInxO19

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    Indium-substituted strontium hexaferrites were prepared by the conventional solid-phase reaction method. Neutron diffraction patterns were obtained at room temperature and analyzed using the Rietveld methods. A linear dependence of the unit cell parameters is found. In3+ cations are located mainly in octahedral positions of 4fVI and 12 k. The average crystallite size varies within 0.84–0.65 μm. With increasing substitution, the TC Curie temperature decreases monotonically down to ~ 520 K. ZFC and FC measurements showed a frustrated state. Upon substitution, the average and maximum sizes of ferrimagnetic clusters change in the opposite direction. The Mr remanent magnetization decreases down to ~ 20.2 emu/g at room temperature. The Ms spontaneous magnetization and the keff effective magnetocrystalline anisotropy constant are determined. With increasing substitution, the maximum of the ε/ real part of permittivity decreases in magnitude from ~ 3.3 to ~ 1.9 and shifts towards low frequencies from ~ 45.5 GHz to ~ 37.4 GHz. The maximum of the tg(α) dielectric loss tangent decreases from ~ 1.0 to ~ 0.7 and shifts towards low frequencies from ~ 40.6 GHz to ~ 37.3 GHz. The low-frequency maximum of the μ/ real part of permeability decreases from ~ 1.8 to ~ 0.9 and slightly shifts towards high frequencies up to ~ 34.7 GHz. The maximum of the tg(δ) magnetic loss tangent decreases from ~ 0.7 to ~ 0.5 and shifts slightly towards low frequencies from ~ 40.5 GHz to ~ 37.7 GHz. The discussion of microwave properties is based on the saturation magnetization, natural ferromagnetic resonance and dielectric polarization types. © 2021, The Author(s).Investigations were performed under financial support from the Russian Science Foundation (Agreement No. 19-19-00694 of 06 May 2019)

    Features of structure, magnetic state and electrodynamic performance of SrFe12-xInxO19

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    Indium-substituted strontium hexaferrites were prepared by the conventional solid-phase reaction method. Neutron diffraction patterns were obtained at room temperature and analyzed using the Rietveld methods. A linear dependence of the unit cell parameters is found. In3+ cations are located mainly in octahedral positions of 4fVI and 12 k. The average crystallite size varies within 0.84-0.65 μm. With increasing substitution, the TC Curie temperature decreases monotonically down to ~ 520 K. ZFC and FC measurements showed a frustrated state. Upon substitution, the average and maximum sizes of ferrimagnetic clusters change in the opposite direction. The Mr remanent magnetization decreases down to ~ 20.2 emu/g at room temperature. The Ms spontaneous magnetization and the keff effective magnetocrystalline anisotropy constant are determined. With increasing substitution, the maximum of the ε/ real part of permittivity decreases in magnitude from ~ 3.3 to ~ 1.9 and shifts towards low frequencies from ~ 45.5 GHz to ~ 37.4 GHz. The maximum of the tg(α) dielectric loss tangent decreases from ~ 1.0 to ~ 0.7 and shifts towards low frequencies from ~ 40.6 GHz to ~ 37.3 GHz. The low-frequency maximum of the μ/ real part of permeability decreases from ~ 1.8 to ~ 0.9 and slightly shifts towards high frequencies up to ~ 34.7 GHz. The maximum of the tg(δ) magnetic loss tangent decreases from ~ 0.7 to ~ 0.5 and shifts slightly towards low frequencies from ~ 40.5 GHz to ~ 37.7 GHz. The discussion of microwave properties is based on the saturation magnetization, natural ferromagnetic resonance and dielectric polarization types.Investigations were performed under financial support from the Russian Science Foundation (Agreement No. 19-19-00694 of 06 May 2019).With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).Peer reviewe
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