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Thin (In, Mn)As layer and (In, Mn)As quantum dots grown on GaAs(001) by low-temperature molecular- beam epitaxy (MBE) is investigated by fluorescence extended x-ray absorption fine structure (EXAFS) measurement using synchroton radiation in order to study the local structures formed around the Mn atoms.

It is known that Cu plays an essential role in reducing the grain size of precipitated bcc Fe(Si) nanocrystallites in a nanocrystalline soft-magnetic Fe85.2Si1B9P4Cu0.8 (NANOMET®) alloys like as an Fe73.5Si13.5B9Nb3Cu1 (FINEMET®). However, significant differences are there between two alloys; NANOMET has much higher iron content (~85%) than FINEMET (73.5%) and the former contains P instead of Nb for the latter. In the present work, the local structure around Cu in FINEMET was measured by X-ray absorption fine structure (XAFS) at 20K and compared with those of NANOMET during nanocrystallization. Definite differences between NANOMET and FINEMET are found in the way of the evolution of Cu clusters during nanocrystallization. In FINEMET, an fcc structure of Cu is recognized in an as-quenched ribbon indicating existence of a small number of Cu clusters or a very small size of Cu clusters which is stable up to 450 °C, while the fcc Cu clusters are developed rapidly above 450 °C. An fcc structure of the Cu clusters in FINEMET is retained all the way to the end of the nanocrystallization. On the contrary, for NANOMET the local structure around Cu changes in a sequence as "amorphous→fcc→bcc→fcc" by annealing. The reasons of such different behaviors of the local structure around Cu during nanocrystallization are discussed in terms of different contributions of Cu clusters in bcc Fe precipitation between FINEMET and NANOMET. A significantly fast crystallization process with an extraordinary large heat release can be another reason for the transition of the local structure around Cu from fcc to bcc for NANOMET. [ABSTRACT FROM AUTHOR]

We have investigated thin (In, Mn)As layer and (In, Mn)As quantum dots (with Mn mole fraction lower than 0.02) on GaAs(001) by fluorescence extended x-ray absorption fine structure (EXAFS) in order to study the local structures formed around the Mn atoms. The EXAFS analysis revealed that in a 10 nm thick (In, Mn)As layer, the In-site substitutional Mn and the NiAs-type MnAs coexisted, while the majority of the Mn atoms were substituted in the In-sites of InAs in (In, Mn)As quantum dots. It is considered that different growth modes for the thin layer and the quantum dots affect the local structures. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

OBJECTIVES: There is little information on geriatric emergency airway management. We sought to describe intubation practices and outcomes for emergency department (ED) geriatric and younger patients in Japan. METHOD: We formed the Japanese Emergency Airway Network, a consortium of 11 medical centers, and prospectively collected data on ED intubations between 2010 and 2011. All patients 18 years or older who underwent emergent airway management were included in our study. Patients were divided to into 2 groups: 18 to 64-year olds and 65 years or older. We present descriptive data as proportions with 95% confidence intervals (CI). RESULTS: The database recorded 3277 patients (capture rate 96%), and 3178 met the inclusion criteria. Of 3178 patients, 1844 (58%) were 65 years or older, 1334 (42%) were 18 to 64 years old, 809 (25%) were 80 years or older, and 407 (50%) of them were in the state of cardiac arrest. The geriatric group, compared to the younger group, had a higher success rate on the initial attempt (71% vs 64%; difference 7%; 95% CI 4%-10%;) and in 2 attempts (90% vs 88%; difference 3%; 95% CI 1%-5%) or less. There was no significant difference in the adverse event rates by age group (difference 0%; 95% CI -2% to 3%). CONCLUSION: In our multicenter study involving a large geriatric population, we found that geriatric patients were intubated with a higher success rate, compared to younger patients. These data provide implications for the geriatric ED airway practice that may lead to better patient-centered emergency care. [ABSTRACT FROM AUTHOR]

We succeeded in growing highly Fe-doped GaN films by solid-source molecular beam epitaxy using an electron-cyclotron-resonance microwave nitrogen plasma. The substrate temperature was in the range of 380-520 °C. The samples were analyzed by x-ray diffraction and transmission electron microscopy, and showed hexagonal (wurtzite) or cubic (zincblende) structure or a mixture of both phases. The Fe concentration was on the order of 10[sup 19] cm[sup -3] and extended x-ray absorption fine structure data show that the Fe is substituting the Ga in GaN. The magnetization measurements as a function of temperature reveal ferromagnetic properties below 100 K for the sample grown at the lowest temperature. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Hexavalent iridium (Ir VI ) oxide is predicted to be more active and stable than any other iridium oxide for the oxygen evolution reaction in acid; however, its experimental realization remains challenging. In this work, we report the synthesis, characterization, and application of atomically dispersed Ir VI oxide (Ir VI - ado ) for proton exchange membrane (PEM) water electrolysis. The Ir VI - ado was synthesized by oxidatively substituting the ligands of potassium hexachloroiridate(IV) (K 2 IrCl 6 ) with manganese oxide (MnO 2 ). The mass-specific activity (1.7 × 10 5 amperes per gram of iridium) and turnover number (1.5 × 10 8 ) exceeded those of benchmark iridium oxides, and in situ x-ray analysis during PEM operations manifested the durability of Ir VI at current densities up to 2.3 amperes per square centimeter. The high activity and stability of Ir VI - ado showcase its promise as an anode material for PEM electrolysis.

Background: Surfer's myelopathy is a non-traumatic spinal cord injury that was first described in a publication in 2004. However, most emergency physicians are not familiar with this rare disease., Case Presentation: The patient was a 19-year-old female novice surfer. She had experienced back discomfort without trauma during her surfing lessons. The discomfort turned to dysesthesia of both legs. She could not walk after 1 h and was brought to our hospital. Physical examination revealed weakness and dysesthesia of both legs, absent deep tendon reflexes, bilaterally positive Babinski reflex, and bladder and rectal disturbance. Spine magnetic resonance imaging revealed T2 prolongation from T7 to the medullary cone. She was diagnosed with surfer's myelopathy and treated conservatively. She recovered well and was discharged on day 28., Conclusion: Emergency physicians must be better informed about surfer's myelopathy. Novice surfers and instructors should be educated on the early signs and symptoms of this condition.