108 research outputs found
Development of ion beam figuring system with electrostatic deflection for ultraprecise X-ray reflective optics
We developed an ion beam figuring system that utilizes electrostatic deflection. The system can produce an arbitrary shape by deterministically scanning the ion beam. The scan of the ion beam, which can be precisely controlled using only an electrical signal, enables us to avoid degradation of the mirror shape caused by imperfect acceleration or deceleration of a mechanically scanning stage. Additionally, this surface figuring method can easily be combined with X-ray metrology because the workpiece remains fixed during the figuring. We evaluated the figuring accuracy of the system by fabricating a plano-elliptical mirror for X-ray focusing. A mirror with a shape error of 1.4 nm root mean square (RMS) with a maximum removal depth of 992 nm, which corresponds to figuring accuracy of 0.14% RMS, was achieved. After the second shape corrections, an elliptical shape with a shape error of approximately 1 nm peak-to-valley, 0.48 nm RMS could be fabricated. Then, the mirror surface was smoothed by a low-energy ion beam. Consequently, a micro-roughness of 0.117 nm RMS, measured by atomic force microscopy, was achieved over an area of 1 × 1 μm2.Jumpei Yamada, Satoshi Matsuyama, Yasuhisa Sano, and Kazuto Yamauchi, "Development of ion beam figuring system with electrostatic deflection for ultraprecise X-ray reflective optics", Review of Scientific Instruments 86, 093103 (2015) https://doi.org/10.1063/1.4929323
Development of concave-convex imaging mirror system for a compact and achromatic full-field x-ray microscope
Jumpei Yamada, Satoshi Matsuyama, Shuhei Yasuda, Yasuhisa Sano, Yoshiki Kohmura, Makina Yabashi, Tetsuya Ishikawa, and Kazuto Yamauchi "Development of concave-convex imaging mirror system for a compact and achromatic full-field x-ray microscope", Proc. SPIE 10386, Advances in X-Ray/EUV Optics and Components XII, 103860C (6 September 2017); https://doi.org/10.1117/12.2272904
Differential expression of nuclear lamin subtypes in the neural cells of the adult rat cerebral cortex
Lamins are type V intermediate filament proteins that are located beneath the inner nuclear membrane. In mammalian somatic cells, LMNB1 and LMNB2 encode somatic lamins B1 and B2, respectively, and the LMNA gene is alternatively spliced to generate somatic lamins A and C. Mutations in lamin genes have been linked to many human hereditary diseases, including neurodegenerative disorders. Knowledge about lamins in the nervous system has been accumulated recently, but a precise analysis of lamin subtypes in glial cells has not yet been reported. In this study we investigated the composition of lamin subtypes in neurons, astrocytes, oligodendrocyte-lineage cells, and microglia in the adult rat cerebral cortex using an immunohistochemical staining method. Lamin A was not observed in neurons and glial cells. Lamin C was observed in astrocytes, mature oligodendrocytes and neurons, but not observed in oligodendrocyte progenitor cells. Microglia also did not stain positive for lamin C which differed from macrophages, with lamin C positive. Lamin B1 and B2 were observed in all glial cells and neurons. Lamin B1 was intensely positive in oligodendrocyte progenitor cells compared with other glial cells and neurons. Lamin B2 was weakly positive in all glial cells compared to neurons. Our current study might provide useful information to reveal how the onset mechanisms of human neurodegenerative diseases are associated with mutations in genes for nuclear lamin proteins
Hard x-ray intensity autocorrelation using direct two-photon absorption
An intensity autocorrelation measurement is demonstrated to characterize a pulse duration of 9-keV x-ray free-electron laser (XFEL) pulses from a split-delay optical (SDO) system with four-bounce silicon 220 reflections in each branch. XFEL pulse replicas with variable time delays are generated by the SDO system itself. High intensity of >2×1016W/cm2 achieved in a self-seeding operation and careful data analysis allow the measurement with direct two-photon absorption. The autocorrelation trace gave a duration of 7.6±0.8fs in full width at half maximum for a Gaussian assumption. Furthermore, the trace shows good agreement with a simulation of the XFEL pulse shape propagating through the SDO system, irrespective of spectral chirps in the original XFEL pulses. Our results open the door toward direct temporal characterization of narrowband XFELs at the hard x-ray regime, such as self-seeded and future cavity-based XFELs, and indicate a solid way for temporal tailoring of ultrafast x-ray pulses with perfect crystals.Osaka T., Inoue I., Yamada J., et al. Hard x-ray intensity autocorrelation using direct two-photon absorption. Physical Review Research, 4, 1, L012035. https://doi.org/10.1103/PhysRevResearch.4.L012035
Distribution and toxicity evaluation of ZnO dispersion nanoparticles in single intravenously exposed mice
ZnO nanoparticles (NPs) have been widely used in various commercial products. Application of ZnO NPs is expected to apply to cancer diagnosis and therapy, used as drug delivery carriers. In the present study, the lethal dose 50 (LD50) of intravenously administered ZnO NPs (0.3 mg/kg) was calculated in mice. Blood kinetics and tissue distribution of a toxic dose of ZnO NPs (0.2 mg/kg, 0.05 mg/kg) were investigated after intravenous exposure. In addition, 8-hydroxy-2’-deoxyguanosine (8-OHdG) was evaluated. Following the injection, ZnO NPs were rapidly removed from the blood and distributed to organs. Pulmonary emphysema was observed pathologically study in mice at 3 days after the 0.2 mg/kg dose and at 6 days after the 0.05 mg/kg dose. ZnO NPs were mainly accumulated in the lung and spleen within 60 min. From the long-term tissue distribution study, the liver showed peak concentration at 6 days, and spleen peaked at 1 day. The lungs kept high levels until 6 days. Tissue distribution and pathological study showed that the spleen, liver, and lungs are target organs for ZnO NPs. Accumulation in the liver and spleen may be due to the phagocytosis by macrophages. A dose-dependent increase in 8-OHdG was observed in mice treated with ZnO NPs. This study is the first to show information on kinetics and target organs following intravenous ZnO injection
Genetic Association Analysis of NOS1 and Methamphetamine-Induced Psychosis Among Japanese
The neuronal nitric oxide synthase gene (NOS1) is located at 12q24, a susceptibility region for schizophrenia, and produces nitric oxide (NO). NO has been reported to play important roles as a gaseous neurotransmitter in brain. NO is a second messenger for the N-methyl-D aspartate (NMDA) receptor and is related to the dopaminergic system. Because the symptomatology of methamphetamine (METH) use disorder patients with psychosis is similar to that of patients with schizophrenia, NOS1 is a good candidate gene for METH-induced psychosis. Therefore, we conducted a case-control association study between NOS1 and METH-induced psychosis with Japanese subjects (183 with METH-induced psychosis patients and 519 controls). We selected seven SNPs (rs41279104, rs3782221, rs3782219, rs561712, rs3782206, rs6490121, rs2682826) in NOS1 from previous reports. Written informed consent was obtained from each subject. This study was approved by the Ethics Committee at Fujita Health University School of Medicine and each participating institute of the Japanese Genetics Initiative for Drug Abuse (JGIDA). No significant association was found between NOS1 and METH-induced psychosis in the allele/genotype-wise or haplotype-wise analyses. In conclusion, we suggest that NOS1 might not contribute to the risk of METH-induced psychosis in the Japanese population
クモマクカ シュッケツ ニ ゾクハツ シタ ジュウショウ ノ Neurogenic stress cardiomyopathy ノ ケントウ
Neurogenic stress cardiomyopathy(NSC)is caused by catecholamine excess and/or sympathetic nerve activation, presented as a transient cardiac wall motion abnormality. It is reported to occur in 4‐15% of patients suffering from subarachnoid hemorrhage(SAH). Of particular concern, severe NSC leading to cardiac dysfunction is especially important to consider when treating SAH patients in the acute stage because it could affect the prognosis of SAH and the timing of surgery. Currently, the incidence of severe NSC and risk factors are not well characterized. In the present study, we reviewed the medical records of85patients(20men,65women)who were admitted and treated for ruptured cerebral aneurysms at Tokushima University Hospital during the period from January 2010 to May 2012. NSC occurred in five patients(5.9%), and three of those patients(3.5%)showed severe NSC with cardiac dysfunction. NSC was observed only in patients with poor SAH-grade, and those resulting in severe cardiac dysfunction were all in women. Notably, the incidence of severe NSC was particularly high in female patients with poor SAH-grades (17.6%). We reported the morbidity of severe NSC in patients with SAH. It is important to pay special attention to severe NSC in female patients, particular those with poor SAH-grades
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