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Abbreviations bvFTD Behavior variant frontotemporal dementia SP 11 sp C-PiB SP 11 sp C-Pittsburgh compound B CBD Corticobasal degeneration DaT Dopamine transporter SP 18 sp F-FDG SP 18 sp F-fluorodeoxyglucose FBS Frontal behavioral-spatial syndrome SP 123 sp I-FP-CIT SP 123 sp I-N- -fluoropropyl-2 -carboxymethoxy-3 -(4-iodophenyl)nortropane MAO-B Monoamine oxidase-B MRI Magnetic resonance imaging PET Positron emission tomography PSP Progressive supranuclear palsy SBR Specific binding ratio SPECT Single-photon emission computed tomography SUV Standardized uptake value References 1 Armstrong MJ, Litvan I, Lang AE, Bak TH, Bhatia KP, Borroni B, Boxer AL, Dickson DW, Grossman M, Hallett M, Josephs KA, Kertesz A, Lee SE, Miller BL, Reich SG, Riley DE, Tolosa E, Troster AI, Vidailhet M, Weiner WJ. Here, we present an autopsy-confirmed case of CBD presenting with FBS who underwent positron emission tomography (PET) with SP 18 sp F-THK5351, visualizing the predominant lesion of the frontal lobes associated with the clinical phenotype. Conventional morphological and functional imaging modalities using brain MRI and SP 18 sp F-FDG PET imaging showed both atrophy and hypometabolism with right-sided predominance, respectively. Dear Sirs, Clinical phenotypes of corticobasal degeneration (CBD) vary and are typically presented with four phenotypes: corticobasal syndrome (CBS), frontal behavioral-spatial syndrome (FBS), nonfluent/agrammatic variant of primary progressive aphasia, and progressive supranuclear palsy syndrome [[1]]. [Extracted from the article]

Background: Normal pressure hydrocephalus (NPH) manifests as gait instability, cognitive impairment, and urinary incontinence. This clinical triad of NPH sometimes occurs with ventriculomegaly in patients with neurodegenerative disease. Patients with pathologically verified neurodegenerative diseases, such as progressive supranuclear palsy (PSP), have received antemortem diagnoses of NPH. Objectives: This study presents clinical and pathological features of a patient with pathologically verified corticobasal degeneration (CBD) coexisting with clinically shunt‐responsive NPH. Methods: We performed clinical, radiological, and pathological evaluations in a patient with CBD whose antemortem diagnosis was PSP Richardson's syndrome (PSP‐RS) coexisting with shunt‐responsive NPH. Results: A 59‐year‐old woman developed bradykinesia and gait instability and then frequent falls, urinary incontinence, and supranuclear vertical gaze palsy followed. At 63 years of age, her gait disturbance and urinary incontinence had deteriorated rapidly, and cognitive impairment was disclosed. There were typical findings of NPH with ventriculomegaly and disproportionately enlarged subarachnoid space hydrocephalus as well as a 2‐layer appearance with decreased and increased cerebral blood perfusion. Shunt placement ameliorated gait instability for more than 1 year and improved radiological indicators of NPH. However, atrophy of the midbrain progressed with time after transient increases in size. Although the antemortem diagnosis was probable PSP‐RS, pathological evaluation verified CBD. There were severe discontinuities of the ependymal lining of the lateral ventricles and subependymal rarefaction and gliosis with tau‐positive deposition. Conclusions: Shunt surgery could ameliorate NPH symptoms in patients with 4‐repeat tauopathies. Careful assessments of clinical findings are necessary to predict the benefits of shunts as a therapeutic option for patients with neurodegenerative diseases coexisting with NPH. [ABSTRACT FROM AUTHOR]

The soft X-ray beamline BL23SU at SPring-8 has undergone an upgrade with a twin-helical undulator of in-vacuum type to enhance the experimental capabilities of the endstations. The new light source with a fast helicity-switching operation allows not only the data throughput but also the sensitivity in X-ray magnetic circular dichroism (XMCD) to be improved. The operational performance and potential are described by presenting XMCD results of paramagnetic β-US2 measured with a 10 T superconducting magnet. [ABSTRACT FROM AUTHOR]

In heavy-fermion compounds, f electrons show both itinerant and localized behaviour depending on the temperature. Above a characteristic temperature, T*, their magnetic properties can be described by completely ‘localized’ f-electron models. On the other hand, well below T*, their Fermi surfaces can be explained by the ‘itinerant’ f-electron model. These two models assume totally different natures of the f electrons, and how they transform between these states as a function of temperature has never been understood at the level of their electronic structures. Here, we use angle-resolved photoelectron spectroscopy to study the band structure of the heavy-fermion antiferromagnetic superconductor UPd2Al3 below and above T*, and find that the f bands, which form the Fermi surfaces at low temperatures, are excluded from the Fermi surfaces at high temperatures. This result demonstrates how the same f electrons can be both itinerant and localized. [ABSTRACT FROM AUTHOR]

Magnetic circular dichroism (MCD) spectra of spinel ferrites MFe[sub 2]O[sub 4] (M = Co, Mn, Fe, Co and Ni) have been measured by using a photon-helicity-switching method. The method achieves high energy resolution and a low noise-to-signal ratio. The Fe L[sub 2,3] absorption spectra of MFe[sub 2]O[sub 4] show a similar spectral profile; on the other hand, the MCD spectra show the characteristic fine structures. These differences are attributed to the variety of 3d electron configuration of Fe ions (Fe[sup 2+] or Fe[sup 3+]) and the local symmetry (tetrahedral or octahedral). The origin of the positive peak of MFe[sub 2]O[sub 4] (M = Fe, Co and Ni) MCD spectra at the L[sub 3] edge is attributed to the tetrahedral Fe[sup 3+] (3d[sup 5]) state. [ABSTRACT FROM AUTHOR]

Riluzole (RZ)-induced interstitial lung disease (RZ-ILD) is a rare and potentially life-threatening adverse event in amyotrophic lateral sclerosis (ALS) patients, which is rarely reported. Therefore, the optimal treatment for RZ-ILD is unclear. We describe herein three Japanese cases of ALS complicated with RZ-ILD, of which two were successfully treated with high-dose steroid therapy. In our all ALS cases with RZ-ILD, the duration of RZ exposure until RZ-ILD onset was within 2 months. All three cases showed respiratory symptoms, dorsal predominant ground-glass opacities by imaging analysis, and abnormal laboratory findings associated with interstitial lung diseases, such as Krebs von den Lungen-6 and surfactant protein-D. Intravenous high-dose steroid therapy together with the discontinuation of RZ in two cases with respiratory symptoms markedly ameliorated their symptoms and abnormal findings of RZ-ILD. One case showed mild respiratory symptoms compared with the others and recovered after the withdrawal of RZ only. According to previous case reports and our cases, RZ-ILD may develop 2 months after initiating RZ and exacerbate respiratory symptoms rapidly in ALS patients with severe respiratory muscle involvement or complicating aspiration pneumonia. Transient high-dose steroid therapy in addition to discontinuation of RZ might be a good therapeutic option for RZ-ILD. • Riluzole-induced interstitial lung disease (RZ-ILD) is a serious adverse event. • RZ-ILD may develop within two months after initiating riluzole treatment. • Transient high-dose steroid therapy might be a good therapeutic option for RZ-ILD. [ABSTRACT FROM AUTHOR]

Herein, we report a novel case of focal task-specific dystonia of the upper extremity that occurred in a 27-year-old man who presented with flexion of the left third, fourth, and fifth fingers exclusively during rhythm gameplay. Dystonia during electronic sports should be recognized as a new type of occupational dystonia. • Actions associated with focal task-specific dystonia vary over time. • This novel case of focal task-specific dystonia of an upper extremity occurred in a 27-year-old man. • Flexion of the left third, fourth, and fifth fingers occurred exclusively during rhythm gameplay. • Dystonia during electronic sports should be recognized as a new type of occupational dystonia. [ABSTRACT FROM AUTHOR]

Abstract: We have performed angle-resolved photoemission experiments for heavy fermion superconductors CeIrIn5 and UPd2Al3. It was found that the Ce 4f electrons in CeIrIn5 are nearly localized, but the small itinerant component also exists in the ARPES spectra. For UPd2Al3, on the other hand, the strongly dispersive bands of U 5f origin were observed, suggesting that the U 5f electronic states are dominated by the itinerant character. We have found that these two compounds have very different natures of f-electrons although both of them show the coexistence or competition of the superconductivity and the magnetic ordering. [Copyright &y& Elsevier]

In order to understand the mechanism of the ferromagnetism in the ferromagnetic semiconductor Ga 1 − x Mn x As [(Ga,Mn)As], we have investigated the magnetic behavior on a microscopic level through systematic temperature (T)- and magnetic field (H)-dependent soft x-ray magnetic circular dichroism (XMCD) experiments at the Mn L 2 , 3 absorption edges. The T and H dependences of XMCD intensities have been analyzed using a model consisting of the ferromagnetic (FM), paramagnetic, and superparamagnetic (SPM) components. Intriguingly, we have found a common behavior for the ferromagnetic ordering process in (Ga,Mn)As samples with different Mn concentrations (4% and 10.8%) and different Curie temperature (T C ) values (65, 120, and 164 K). In particular, the SPM component develops well above T C , indicating that local FM regions are formed well above T C . The present findings indicate that the onset of ferromagnetic ordering is triggered by local electronic states around the substitutional Mn ions rather than uniform electronic states considered by mean-field theories. Insight into the most representative ferromagnetic semiconductor, (Ga,Mn)As, provided by the present study will be an important step in understanding the mechanism of ferromagnetic ordering in various ferromagnetic semiconductor families. [ABSTRACT FROM AUTHOR]

To identify the bonding sites of initial radiation interaction with DNA and to trace the following chemical reaction sequences on the pathway of damage induction, we carry out a spectroscopy XIL (X-ray induced luminescence) using soft X-ray synchrotron radiation. This is a nondestructive analysis of the excited intermediate species produced in a molecular mechanism on the damage induction pathway. We introduce aqueous samples of UMP (uridine-5'-monophosphate) in the vacuum by the use of a liquid micro-jet technique. The luminescence in the region of UV-VIS (from visible to ultraviolet) radiation induced after the absorption of monochromatic soft X-ray by aqueous UMP is measured with sweeping the soft X-ray energy in the region of 370–560 eV. The enhanced XIL intensities for aqueous UMP in the region of soft X-ray of 410–530 eV (in "water window" region) are obtained. The enhancement of XIL intensities in the UV-VIS region, relative to the water control, is explained by the excitation and ionization of a K-shell electron of nitrogen atoms in the uracil moiety. The enhanced XIL intensities do not match the structure of XANES (X-ray absorption near-edge structure) of the aqueous UMP. This suggests that the XIL intensities reflect the quantum yields of luminescence, or the quantum yields for conversion by UMP of an absorbed X-ray into UV-VIS radiation. In this paper, spectra of luminescence are shown to be resolved by combining low pass filters. The filtered luminescence spectra are obtained at the center of gravity (λc) of the band pass wavelength regions at λc = 270nm, 295 nm, 340 nm, 385 nm, 450 nm, and 525 nm., which show a trend similar to the fluorescence of nucleobases induced by ultraviolet radiation. It is concluded that the origin of the observed XIL is the hydrated uracil moiety in aqueous UMP, decomposition of which is suppressed by the migration of excess charge and internal energy after the double ionization due to Auger decay. [ABSTRACT FROM AUTHOR]

Abstract: We have observed the band structure and Fermi surfaces of the heavy Fermion superconductor by angle-resolved photoemission experiments in the soft X-ray region. We observed renormalized quasi-particle bands in the vicinity of the Fermi level and strongly dispersive bands on the higher binding energy side. Our observation suggests that the structure previously assigned to contributions from localized states in the U 5f spectrum has strong energy dispersions. [Copyright &y& Elsevier]

Introduction: Idiopathic rapid eye movement sleep behavior disorder (iRBD) is one of the most specific prodromal symptoms of synucleinopathies, including Parkinson's disease (PD) and multiple system atrophy. The Japan Parkinson's Progression Markers Initiative (J-PPMI) was a prospective cohort study conducted in Japanese patients with iRBD to investigate biomarkers for prodromal synucleinopathies. We carried out an initial assessment of the J-PPMI study to reveal the factors correlated with dopamine transporter single-photon emission computed tomography (DaT) and 123I-meta-iodobenzylguanidine (MIBG) myocardial scintigraphy.Methods: This cross-sectional study was conducted in 108 patients with iRBD, selected from the J-PPMI study. We divided the patients into four groups based on the MIBG and DaT results. We also recorded the patients' demographics and clinical data. Following PD probability calculation, we examined the biomarkers associated with DaT and MIBG.Results: Ninety-five of the enrolled patients (88%) met the diagnostic criteria for prodromal PD based on the probability score. Only five patients had normal MIBG and DaT. We identified 29 cases with decreased DaT and MIBG, all of whom met the above diagnostic criteria. Both DaT and MIBG were significantly correlated with the Japanese version of the Montreal Cognitive Assessment (MoCA-J) score.Conclusion: Both DaT and MIBG are important biomarkers for confirming synucleinopathies and/or staging disease progression. Although 95% of iRBD patients were consistent with the body-first subtype concept, alpha-synuclein pathologies of iRBD might have widespread systemic involvement rather than being confined to the lower brainstem, particularly in patients with reduced MoCA-J scores. [ABSTRACT FROM AUTHOR]

Magnetic circular dichroism (MCD) spectra of CrFe[sub 2]O[sub 4] have been measured by using the helicity switching method. The method achieves a high signal-to-noise ratio and resolved the fine structure in these spectra. The theoretical spectra, which were calculated by the charge transfer model, reproduced the experimental spectra. The origin of three negative peaks around the L[sub 3] edge in Cr 2p-MCD is attributed to the d[sup 4]L electron configuration in the initial state. [ABSTRACT FROM AUTHOR]

Angle-resolved photoemission in the soft X-ray region has so far been used to study crystal (surface) structure by using photoelectron diffraction phenomena. In this energy region, the observation of the band structure was considered to be difficult, because the momentum of the incident photon cannot be negligible, the emitted electron is strongly influenced by the electron diffraction effects, and the cross section of the valence band is very small. We have performed the angle-resolved photoemission from the valence bands of highly oriented pyrolytic graphite by using the soft X-ray (hν = 980 eV) and successfully observed the band structure. The appearance of the structures of the band density of state is also discussed. Since the escape depth for the electrons with high kinetic energies is longer than ARUPS, this experimental method is better than the usual ARUPS in order to study the bulk band structures in solids. [ABSTRACT FROM AUTHOR]

The N K-edge X-ray absorption near edge structure (XANES) spectra of the purine-containing nucleotide, guanosine 5'-monophosphate (GMP), in aqueous solution are measured under various pH conditions. The spectra show characteristic peaks, which originate from resonant excitations of N 1s electrons to n * orbitals inside the guanine moiety of GMP. The relative intensities of these peaks depend on the pH values of the solution. The pH dependence is explained by the core-level shift of N atoms at specific sites caused by protonation and deprotonation. The experimental spectra are compared with theoretical spectra calculated by using density functional theory for GMP and the other purine-containing nucleotides, adenosine 5'-monophosphate, and adenosine 5'-triphosphate. The N K-edge XANES spectra for all of these nucleotides are classified by the numbers of N atoms with particular chemical bonding characteristics in the purine moiety. [ABSTRACT FROM AUTHOR]

The polyglutamine (polyQ) diseases are a group of inherited neurodegenerative diseases that include Huntington's disease, various spinocerebellar ataxias, spinal and bulbar muscular atrophy, and dentatorubral pallidoluysian atrophy. They are caused by the abnormal expansion of a CAG repeat coding for the polyQ stretch in the causative gene of each disease. The expanded polyQ stretches trigger abnormal β-sheet conformational transition and oligomerization followed by aggregation of the polyQ proteins in the affected neurons, leading to neuronal toxicity and neurodegeneration. Disease-modifying therapies that attenuate both symptoms and molecular pathogenesis of polyQ diseases remain an unmet clinical need. Here we identified arginine, a chemical chaperone that facilitates proper protein folding, as a novel compound that targets the upstream processes of polyQ protein aggregation by stabilizing the polyQ protein conformation. We first screened representative chemical chaperones using an in vitro polyQ aggregation assay, and identified arginine as a potent polyQ aggregation inhibitor. Our in vitro and cellular assays revealed that arginine exerts its anti-aggregation property by inhibiting the toxic β-sheet conformational transition and oligomerization of polyQ proteins before the formation of insoluble aggregates. Arginine exhibited therapeutic effects on neurological symptoms and protein aggregation pathology in Caenorhabditis elegans, Drosophila, and two different mouse models of polyQ diseases. Arginine was also effective in a polyQ mouse model when administered after symptom onset. As arginine has been safely used for urea cycle defects and for mitochondrial myopathy, encephalopathy, lactic acid and stroke syndrome patients, and efficiently crosses the blood-brain barrier, a drug-repositioning approach for arginine would enable prompt clinical application as a promising disease-modifier drug for the polyQ diseases. [ABSTRACT FROM AUTHOR]

Background: A newer generation neuropsychological tests can take advantage of touch screen and mobile technology. We have developed a new Android application termed "User eXperience-Trail Making Test (UX-TMT)" for neurocognitive assessment and training. This study investigated the utility, including the reliability and the validity, of the UX-TMT as a screening test for cognitive decline in adults. Methods: A total of 84 individuals aged 27–86 years were divided into three groups; healthy controls ([HC] n = 29), people with Parkinson's disease (PD; n = 28), and people with mild cognitive impairment (MCI) and dementia (MCI&D; n = 27). We examined the distributions of the scores and the time required, and the effects of age and group on these distributions. We analyzed internal consistency and convergent validity in all samples and applied receiver operator characteristic (ROC) analysis to determine a cutoff score that could differentiate the MCI & D group from the HC group. Results: 97.6% of the participants completed all of the tasks, and the average total test time required for UX-TMT was 428.8 (± 109.1) s in the HC, 542.0 (± 168.7) s in the PD, and 777.5 (± 256.1) s in the MCI&D groups, respectively. The MCI&D group showed significantly lower UX-TMT scores and longer total time in completing the task than the HC group. In an ROC analysis, a score of 21 showed high sensitivity (.83) and specificity (.92), and the UX-TMT score plus age improved sensitivity to.96. Additionally, the UX-TMT scores showed significant correlation with the Mini-Mental State Examination (Japanese version) scores (r =.77, p =.001), and Cronbach's alpha (.71–.83) indicated acceptable internal consistency. Conclusion: The UX-TMT demonstrated high reliability and validity to detect cognitive decline in Japanese adults, highlighting its utility as a screening tool for epidemiological and clinical research. [ABSTRACT FROM AUTHOR]

Recent progresses in the soft X-ray photoelectron spectroscopy (PES) studies ( hν ≳ 100 eV) for uranium compounds are briefly reviewed. The soft X-ray PES has enhanced sensitivities for the bulk U 5 f electronic structure, which is essential to understand the unique physical properties of uranium compounds. In particular, the recent remarkable improvement in energy resolutions from an order of 1 eV to 100 meV made it possible to observe fine structures in U 5 f density of states. Furthermore, soft X-ray ARPES becomes available due to the increase of photon flux at beamlines in third generation synchrotron radiation facilities.The technique made it possible to observe bulk band structures and Fermi surfaces of uranium compounds and therefore, the results can be directly compared with theoretical models such as band-structure calculations. The core-level spectra of uranium compounds show a systematic behavior depending on their electronic structures, suggesting that they can be utilized to determine basic physical parameters such as the U 5 f -ligand hybridizations or Comlomb interaction between U 5 f electrons. It is shown that soft X-ray PES provides unique opportunities to understand the electronic structures of uranium compounds. [ABSTRACT FROM AUTHOR]

Highlights: [•] XANES for adenine nucleotides in aqueous solutions at N K-edge are measured. [•] XANES spectra showed pH value dependence. [•] The pH value dependence is explained as due to protonation of N1 atom in adenine. [•] This explanation is consistent with the published results for gas phase adenine. [ABSTRACT FROM AUTHOR]

We evaluated electronic structures and magnetic moments in Co3FeN epitaxial films on SrTiO3(001). The experimentally obtained hard x-ray photoemission spectra of the Co3FeN film have a good agreement with those calculated. Site averaged spin magnetic moments deduced by x-ray magnetic circular dichroism were 1.52 μB per Co atom and 2.08 μB per Fe atom at 100 K. They are close to those of Co4N and Fe4N, respectively, implying that the Co and Fe atoms randomly occupy the corner and face-centered sites in the Co3FeN unit cell. [ABSTRACT FROM AUTHOR]

Soft x-ray angle-resolved photoemission experiments have been performed to investigate the band structure and Fermi surface of UPd3. We have observed three U 5f derived bands whose bandwidths are very narrow. Two of these bands appear around 0.8 eV and are slightly separated by about 0.2 eV. The presence of two bands at nearly the same energy might be due to the presence of the two inequivalent U sites. The other U 5f band appears around 1.8 eV. The energy separation between dus band and the two nearly degenerate bands agrees with the 5f1 -final-state multiplet model. In the vicinity of Fermi level, several highly dispersive bands, which form a holelike Fermi surface centered at the Γ point and an electronlike Fermi surface at the K point, were observed. These dispersive valence bands are qualitatively explained by a band structure calculation that assumes a localized 5f2 configuration. All these experimental observations are consistent with the localized U 5f nature. [ABSTRACT FROM AUTHOR]

The electronic structure of the antiferromagnet uranium nitride (UN) has been studied by angle-resolved photoelectron spectroscopy (ARPES) using soft x-rays (h v = 420-520 eV). Strongly dispersive bands with large contributions from the U 5/ states were observed in ARPES spectra and form Fermi surfaces. The band structure as well as the Fermi surfaces in the paramagnetic phase are well explained by the band-structure calculation treating all the U 5/ electrons as being itinerant, suggesting that an itinerant description of the U 5/ states is appropriate for this compound. On the other hand, changes in the spectral function due to the antiferromagnetic transition were very small. The shapes of the Fermi surfaces in a paramagnetic phase are highly three:dimensional, and the nesting of Fermi surfaces is unlikely as the origin of the magnetic ordering. [ABSTRACT FROM AUTHOR]

We have performed angle-resolved photoelectron spectroscopy experiments in the soft x-ray region in order to clarify the band structure and Fermi surfaces (FSs) of URu2Si2. In the vicinity of the Fermi level, U 5f-derived quasiparticle bands were clearly observed. They form a small and a large hole FS centered at the Z point and a large electron FS centered at the Γ point. The overall band structure as well as the FSs are explained by a band structure calculation treating all U 5f electrons as being itinerant. The observed FSs have nesting vectors which give a possible explanation for the spin fluctuations observed by inelastic neutron scattering measurements. [ABSTRACT FROM AUTHOR]

Abstract: The X-ray absorption of nucleotides (adenosine-5′-monophosphate, guanosine 5′-monophosphate, and cytidine 5′-monophosphate) are measured in both water solutions and thin solid films at X-ray energies near the nitrogen K-edge in the ‘water-window’ region. Each spectrum corresponds to the selective excitation of a nucleobase site in a nucleotide, and thus has features similar to the spectrum of the corresponding nucleobase. An additional new peak in the energy region of the nitrogen 1s→π* resonance is observed for each nucleotide. No significant difference between the water solutions and thin solid films is found, which might be attributable to the hydrophobic properties of a nucleobase in a nucleotide. [Copyright &y& Elsevier]

Abstract: A new spectroscopy to identify the hydration structure playing important role in liquid-phase radiation damage is in progress using a laminar liquid water jet sample in vacuum in combination with soft X-ray synchrotron radiation. We present the total and partial electron yields for liquid water using a photoelectron spectroscopy. Partial electron yields for the Auger transition are obtained for the first time by measuring the electrostatically dispersed electron kinetic energy spectra as a function of photon energy of synchrotron radiation. [Copyright &y& Elsevier]

Abstract: A new spectroscopy for direct effect of radiation damage to nucleic acids such as DNA and RNA is underway using a liquid beam sample in vacuum combined with soft-X-ray synchrotron radiation. We show the X-ray absorption spectrum (XANES) of liquid phase water at X-ray photon energy in the vicinity of oxygen K-shell absorption edge obtained from total photoelectron yields ejected from a pure water beam. We confirm a “liquid sample in vacuum” for the present experiment by the measurements of the temperature dependence of the XANES spectrum for a liquid beam of pure water. Shown is the first measurement of the XANES spectrum for guanosine--monophosphate (GMP), which is one of the fundamental nucleotide unit for RNA, in water solution at X-ray photon energy in the vicinity of nitrogen K-shell absorption edge involved in the ‘water-window’ region, which corresponds to a selective excitation of guanine site. [Copyright &y& Elsevier]

The polarization performance of a reflection-type polarizer made with a synthetic mica (fluorophlogopite) single crystal (002) in symmetric Bragg geometry was evaluated at the photon energy of 880 eV by means of the rotating-analyzer method. An experiment was performed at the undulator beamline at the SPring-8. The reflectance in the s-polarization configuration was 2.6% at an incidence angle of around 45°. As the result of the analysis based on the rotating-analyzer method, the polarizance of the polarizer and the degree of linear polarization of the incident light at 880 eV were found to be 0.997±0.002 and 0.993±0.004, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Acetoacetyl-CoA synthetase (AACS, acetoacetate-CoA ligase, EC 6.2.1.16) is a novel cytosolic ketone body (acetoacetate)-specific ligase, the physiological role of which remains to be elucidated. We examined the expression profiles of AACS mRNA in adult rat tissues, finding that it was particularly abundant in male subcutaneous white adipose tissue after weaning. In white adipose tissue, AACS mRNA was preferentially detected in mature adipocytes but not in preadipocytes. The AACS mRNA expression in primary preadipocytes increased during the adipocyte differentiation. These expression profiles were similar to that of acetyl-CoA carboxylase-1, but not like to that of 3-hydroxy-3-methylglutaryl-CoA reductase. These results suggest that AACS in adipose tissue plays an important role in utilizing ketone body for the fatty acid-synthesis during adipose tissue development. [Copyright &y& Elsevier]

A stereograph of atomic arrangement was displayed directly on the screen of display-type spherical-mirror analyzer without any computer-aided conversion process for the first time. This stereoscopic photograph enables viewing three-dimensional atomic arrangement. This technique was realized taking advantage of the phenomenon of circular dichroism in photoelectron angular distribution. The azimuthal shifts of forward focusing peaks in a photoelectron angular distribution taken with left and right helicity light in a special arrangement are the same as the parallaxes in a stereo view of atoms. Hence a stereoscopic recognition of three-dimensional atomic arrangement is possible, when the left eye and the right eye respectively view the two images obtained by left and right helicity light simultaneously. [Copyright &y& Elsevier]

We have performed Co 2p X-ray absorption spectroscopy (XAS) on a mixed valence hexagonal layered system NaCo[sub 2]O[sub 4], which shows large thermopower and metallic conductivity. We also measured XAS for SrCoO[sub 3] and LaCoO[sub 3] as examples of typical Co ionic states. The Co ions of the last two materials are octahedrally surrounded by oxygen atoms. A Co atom in NaCo[sub 2]O[sub 4] also has octahedral coordination with oxygen atoms but it is distorted slightly. The Co ions in SrCoO[sub 3] and LaCoO[sub 3] are in the d[sup 5] and d[sup 6] configuration respectively. The spectrum of NaCo[sub 2]O[sub 4] resembles that of LaCoO[sub 3] rather than that of SrCoO[sub 3]; the Co ions in NaCo[sub 2]O[sub 4] can be regarded as the d[sup 6] configuration. Also, we have tried to calculate the XAS spectra by using the charge-transfer multiplet model (CT-M). Although we could not find out the best-fitting parameters, the results suggested the itinerancy of the Co 3d states. [ABSTRACT FROM AUTHOR]

Heusler alloys are a material class exhibiting various magnetic properties, including antiferromagnetism. A typical application of antiferromagnets is exchange bias that is a shift of the magnetization curve observed in a layered structure consisting of antiferromagnetic and ferromagnetic films. In this study, a layered sample consisting of a Heusler alloy, Mn 2 VAl and a ferromagnet, Fe, is selected as a material system exhibiting exchange bias. Although the fully ordered Mn 2 VAl is known as a ferrimagnet, with an optimum fabrication condition for the Mn 2 VAl layer, the Mn 2 VAl/Fe layered structure exhibits exchange bias. The appearance of the antiferromagnetic property in the Mn 2 VAl is remarkable; however, the details have been unclear. To clarify the microscopic aspects on the crystal structures and magnetic moments around the Mn 2 VAl/Fe interface, cross-sectional scanning transmission electron microscope (STEM) observation, and synchrotron soft X-ray magnetic circular dichroism (XMCD) measurements were employed. The high-angle annular dark-field STEM images demonstrated clusters of Mn 2 VAl with the L2 1 phase distributed only around the interface to the Fe layer in the sample showing the exchange bias. Furthermore, antiferromagnetic coupling between the Mn- and Fe-moments were observed in element-specific hysteresis loops measured using the XMCD. The locally ordered L2 1 phase and antiferromagnetic Mn-moments in the Mn 2 VAl were suggested as important factors for the exchange bias. [ABSTRACT FROM AUTHOR]

5-nm thick Co4N layers capped with 3-nm thick Au layers were grown epitaxially on SrTiO3(001) substrates by molecular beam epitaxy using solid Co and a radio-frequency NH3 plasma. Spin and orbital magnetic moments of the Co4N layers were estimated using x-ray magnetic circular dichroism (XMCD) measurements at 300 K. The site-averaged Co 3d spin magnetic moment is evaluated to be about 1.4 μB, which is smaller than that predicted theoretically (1.58 μB). The element-specific XMCD intensities for the Co L3 edge and N K edge show that the magnetic moment is induced at the N atoms. [ABSTRACT FROM AUTHOR]

Abstract: We have studied the electronic and magnetic properties of epitaxially grown (, 0.5) thin films by X-ray magnetic circular dichroism (XMCD) and hard X-ray photoemission spectroscopy (HXPES). The XMCD studies indicated that the spin moments of Mn and Ru are aligned in the opposite directions. The HXPES spectra indicated the Ru 4d states at around the Fermi edge and the Mn 3d states below . From these results, we propose that the localized Mn 3d states and the itinerant Ru 4d band are antiferromagnetically coupled and give rise to ferromagnetism, in analogy with the mechanism proposed for the double perovskite oxides such as . [Copyright &y& Elsevier]

Abstract: We have carried out the angle-resolved photoemission experiments on some uranium compounds using soft X-ray synchrotron radiation. Bulk- and U 5f-sensitive band structure and Fermi surface were obtained for paramagnetic uranium compound . Although the agreement between the experimental band structure and the LDA calculation treating U 5f electrons as being itinerant is qualitative, the topology of the Fermi surface is well explained by the calculation, suggesting that the U 5f states can be essentially understood within the itinerant-electron model. [Copyright &y& Elsevier]