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The article presents a case of a 63-year old woman with drug-induced hepatitis. The patient had an episode of melena on the second hospital day. It was revealed at upper gastrointestinal endoscopy, that her entire esophagus was black and friable. She was diagnosed of having acute esophageal necrosis.

Background: Bone mineral density (BMD) is a primary risk factor for hip fracture. We studied the effect of long-term weighted vest plus jumping exercise on hip BMD in postmenopausal women as a strategy for reducing hip fracture risk.Methods: Eighteen postmenopausal women (age = 64.1 +/- 1.6 years at baseline, 69.9 +/- 1.6 years at post-testing) who had participated in a 9-month exercise intervention volunteered for the long-term trial. Nine of the original group engaged in weighted vest plus jumping exercise three times per week for 32 weeks of the year over a period of 5 years. Nine of the original controls were active but not enrolled in the exercise program. BMD of the proximal femur was assessed by dual energy x-ray absorptiometry at baseline and after 5 years.Results: At baseline, groups were similar for age, weight, height, years past menopause, and BMD of the femoral neck, trochanter, and total hip. At follow-up, differences in BMD at all regions of the hip were higher in exercisers than controls. For exercisers, changes in BMD were + 1.54% +/- 2.37%, -0.24% +/- 1.02%, and -0.82% +/- 1.04% (means + SE) at the femoral neck, trochanter, and total hip, respectively; controls decreased at all sites (-4.43% +/- 0.93%. 3.43% +/- 1.09%, and -3.80% +/- 1.03%, respectively).Conclusions: A 5-year program of weighted vest plus jumping exercise maintains hip BMD by preventing significant bone loss in older postmenopausal women. Furthermore, this particular program appears to promote long-term adherence and compliance, as evidenced by the commitment of the exercisers for more than 5 years. [ABSTRACT FROM AUTHOR]

Different models have been used to evaluate the interfacial Dzyaloshinskii–Moriya interaction (DMI) from the asymmetric bubble expansion method using magneto-optics. Here, we investigate the most promising candidates over a range of different magnetic multilayers with perpendicular anisotropy. Models based on the standard creep hypothesis are not able to reproduce the domain wall (DW) velocity profile when the DW roughness is high. Our results demonstrate that the DW roughness and the interface roughness of the sample layers are correlated. Furthermore, we give guidance on how to obtain reliable results for the DMI value with this popular method. A comparison of the results with Brillouin light scattering (BLS) measurements on the same samples shows that the BLS approach often results in higher measured values of DMI. [ABSTRACT FROM AUTHOR]

We describe a patient with acute promyelocytic leukemia (APL) who was successfully induced into remission with all-trans retinoic acid (ATRA) and idarubicin, but developed myelodysplastic syndrome (MDS) with monosomy 7 shortly after conclusion of maintenance therapy with idarubicin alternating with 6-mercaptopurine, vincristine, methotrexate and prednisone. Patients on combination regimens of ATRA or other retinoids and chemotherapy, which are being increasingly used in recent years, should be closely monitored for the development of potentially new complications including MDS. [ABSTRACT FROM AUTHOR]

X-ray diffraction (XRD), magnetometry, and ferromagnetic resonance (FMR) measurements were performed on sputtered thin films of the nominal Heusler alloy (Co2Mn)1-xGex with varying Ge content and annealing temperatures. XRD indicates some degree of B2 alloy formation, with strong (110) texturing. FMR measurements were performed in a perpendicular geometry that minimized the contribution of two-magnon scattering to the linewidth. The FMR data indicate a significant increase in linewidth for samples that lack a well-defined (220) peak, presumably as a result of inhomogeneous line broadening. Samples annealed at 200?°C exhibit decreasing Landau-Lifshitz damping with increasing Ge content, while samples annealed at 245 and 300?°C have a nonlinear dependence of linewidth on frequency. The nonlinear component of the linewidth data was successfully fit with a generalized theory of slowly relaxing impurities, originally proposed by Van Vleck and Orbach. The modified theory includes the possibility of transverse coherence during the relaxation process. Magnetometry and FMR spectroscopy results were analyzed in the context of Malozemoff's generalized Slater-Pauling (GSP) theory, with the conclusion that the Ge sites support a significant negative-polarized spin density of several tens of percent. The GSP analysis results were consistent with a more conventional analysis of the spectroscopic g-factor that is appropriate for alloys. The proportionality of the strength of the slow-relaxer contribution to the damping suggests that the negatively polarized Ge atoms are acting as the slowly relaxing impurities in question. [ABSTRACT FROM AUTHOR]

Motivated by the importance of magnetization dynamics in nanomagnets for the development and optimization of magnetic devices and sensors, we measured and modeled spin wave spectra in patterned elliptical nanomagnets. Ferromagnetic resonance spectra for multiple nanomagnets of Ni80Fe20, fabricated by electron-beam lithography to have nominal short-axes of 200 nm or 100 nm, were measured by use of heterodyne magneto-optical microwave microscopy. Scanning electron microscope images taken of the same nanomagnets were used to define element shapes for micromagnetic simulations. The measured spectra show significant differences between nominally identical nanomagnets, which could be only partially attributed to uncontrolled shape variations in the patterning process, as evidenced by the limited agreement between the measured and simulated spectra. Agreement between measurements and simulations was improved by including a zone of reduced magnetization and exchange at the edges of the nanomagnets in the simulations. Our results show that the reduction of shape variations between individual magnetic random-access memory elements can potentially improve their performance. However, unambiguous determination of materials parameters in nanomagnets based on analysis and modeling of spin wave spectra remains problematic. [ABSTRACT FROM AUTHOR]

We studied the microwave assisted magnetic reversal of 65×71 nm2 elliptical Ni80Fe20 nanomagnets. Hysteresis curves were measured by magneto-optical Kerr effect for a range of microwave frequencies and amplitudes. The coercive field Hc was reduced by 26% for an rf field of 0.08Hc when the microwave frequency coincided with the minimum of the experimentally determined ferromagnetic resonance frequency with varying dc field. The experimental results for the fractional reduction in Hc with rf field amplitude are in good agreement with numerical simulations for an array of interacting macrospins with a physically realistic shape anisotropy distribution. [ABSTRACT FROM AUTHOR]

Skyrmions can be stabilized in magnetic systems with broken inversion symmetry and chiral interactions, such as Dzyaloshinskii-Moriya interactions (DMI). Further, compensation of magnetic moments in ferrimagnetic materials can significantly reduce magnetic dipolar interactions, which tend to favor large skyrmions. Tuning DMI is essential to control skyrmion properties, with symmetry breaking at interfaces offering the greatest flexibility. However, in contrast to the ferromagnet case, few studies have investigated interfacial DMI in ferrimagnets. Here we present a systematic study of DMI in ferrimagnetic CoGd films by Brillouin light scattering. We demonstrate the ability to control DMI by the CoGd cap layer composition, the stack symmetry and the ferrimagnetic layer thickness. The DMI thickness dependence confirms its interfacial nature. In addition, magnetic force microscopy reveals the ability to tune DMI in a range that stabilizes sub-100 nm skyrmions at room temperature in zero field. Our work opens new paths for controlling interfacial DMI in ferrimagnets to nucleate and manipulate skyrmions. [ABSTRACT FROM AUTHOR]