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1.
Appl Opt ; 55(5): 1164-9, 2016 Feb 10.
Article in English | MEDLINE | ID: mdl-26906392

ABSTRACT

We demonstrate frequency offset locking between two laser sources using a waveguide-type electro-optic modulator (EOM) with 10th-order sidebands for magneto-optical trapping of Fr atoms. The frequency locking error signal was successfully obtained by performing delayed self-homodyne detection of the beat signal between the repumping frequency and the 10th-order sideband component of the trapping light. Sweeping the trapping-light and repumping-light frequencies with keeping its frequency difference of 46 GHz was confirmed over 1 GHz by monitoring the Doppler absorption profile of I2. This technique enables us to search for a resonance frequency of magneto-optical trapping of Fr.

2.
Rev Sci Instrum ; 85(2): 02A732, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24593466

ABSTRACT

The search for the violation of the fundamental symmetry in a radioactive atom is the promising candidate for precision tests of the standard model and its possible extensions. The subtle signal arising from the symmetry violation is enhanced in heavy atoms, such as a francium (Fr). To realize high precision measurements, a large amount of radioactive isotopes is required. The Fr is produced via a nuclear fusion reaction using a melted gold target with a (18)O primary beam at Cyclotron and Radioisotope Center, Tohoku University. The maximum extraction efficiency of the Fr ion was achieved at approximately 35%. The beam line consists of an electrostatic deflector, three electrostatic quadrupole triplets to the measurement area at 10 m away from the reaction point, and several beam diagnosis systems. We optimized parameters of the beam line.

3.
Phys Rev Lett ; 102(8): 085502, 2009 Feb 27.
Article in English | MEDLINE | ID: mdl-19257752

ABSTRACT

We present an experimental demonstration of an ingenious technique to control the alignment of the atomic internal state in the x-ray region using a periodic crystal field. The alignment directions of Ar16+ and Fe24+ ions were readily controlled by selecting the array of atomic planes using three-dimensional resonant coherent excitation, and were probed via the anisotropy of the deexcitation x-ray emission. We applied this method to a double resonance experiment, and succeeded in controlling the population of the specific magnetic substate in a Lambda-type three-level configuration.

4.
Phys Rev Lett ; 101(11): 113201, 2008 Sep 12.
Article in English | MEDLINE | ID: mdl-18851279

ABSTRACT

We report the Autler-Townes doublet demonstrating a novel type of coherent interaction of atoms not with photons but with a periodic crystal field when the atom is in flight through a crystal at high velocity. It was observed by the nonoptical X-VUV (vacuum-ultraviolet) double resonance of three-dimensional resonant coherent excitation with good coherence. The states strongly coupled in the VUV region were probed by the excitation in the x-ray region. The characteristic spectra are well interpreted by an analogy of the dressed atom concept often adopted for the atom-photon interaction.

5.
Phys Rev Lett ; 97(13): 135503, 2006 Sep 29.
Article in English | MEDLINE | ID: mdl-17026044

ABSTRACT

We have observed resonant coherent excitation (RCE) of H-like Ar(17+) ions traveling through a 1 microm-thick Si crystal at an energy of 391 MeV/u in the nonchanneling condition. A three-dimensional periodic array of atomic planes induces RCE of the nonchanneling ions. The high energy heavy ions together with the thin crystal allow us to observe this new RCE through the measurements of the charge-state distribution of the emerging ions. The observed resonances are much narrower than those of planar-channeling ions due to the absence of the large Stark shift caused by the planar potential.

6.
Phys Rev Lett ; 96(9): 095301, 2006 Mar 10.
Article in English | MEDLINE | ID: mdl-16606273

ABSTRACT

The longitudinal electronic spin relaxation time of Cs atoms optically polarized in superfluid helium (He II, 1.5 K) has been measured with special care to cope with a serious decrease in the number of Cs atoms in the observation region. This decrease, mainly caused by helium convection in introducing the atoms into He II by laser sputtering, was significantly reduced using a new atom implantation method. Combined with a careful correction for the number of atoms, we have determined the relaxation time to be 2.24(19) s or longer, roughly twice as long as that in solid He.

7.
Phys Rev Lett ; 95(25): 253003, 2005 Dec 16.
Article in English | MEDLINE | ID: mdl-16384456

ABSTRACT

We demonstrate that transitions between Zeeman-split sublevels of Rb atoms are resonantly induced by the motion of the atoms (velocity: approximately 100 m/s) in a periodic magnetostatic field (period: 1 mm) when the Zeeman splitting corresponds to the frequency of the magnetic field experienced by the moving atoms. A circularly polarized laser beam polarizes Rb atoms with a velocity selected using the Doppler effect and detects their magnetic resonance in a thin cell, to which the periodic field is applied with the arrays of parallel current-carrying wires.

8.
Int Arch Occup Environ Health ; 77(7): 461-70, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15558298

ABSTRACT

OBJECTIVES: As the airtightness of dwellings has recently increased, problems associated with indoor air pollution and dampness have become important environmental health issues. The aim of this study was to clarify whether symptoms in residents living in newly built dwellings were related to chemicals and dampness. METHODS: Symptoms of 317 residents were surveyed by standardized questionnaires, and the concentrations of formaldehyde, acetaldehyde, and 17 volatile organic compounds (VOCs) in their homes were measured. Dampness (condensation on window panes and/or walls, and mold growth) was identified by questionnaires given to the householders or their partners. RESULTS: Some VOCs (toluene, butyl acetate, ethylbenzene, alpha-pinene, p-dichlorobenzene, nonanal, and xylene) were significantly related to the symptoms, and the sum of all VOCs (all identified VOCs) was significantly related to throat and respiratory symptoms [odds ratio (OR) for eye symptoms =2.4; 95% confidence interval (CI) 1.0-5.5], although the concentrations of VOCs were relatively low. As for the dampness index, condensation on window panes and/or walls was related to all symptoms, and mold growth was related to all symptoms except skin, throat and respiratory and general symptoms. As the number of dampness signs increased, the ORs increased for the symptoms except general symptoms (OR for nose symptoms = 4.4, 95% CI 1.6-11.9). CONCLUSION: Both VOCs and dampness were significantly related to symptoms. We should take measures to reduce the concentrations of VOCs, dampness and microbial growth in dwellings.


Subject(s)
Air Pollution, Indoor/analysis , Hazardous Substances/analysis , Humidity , Sick Building Syndrome/epidemiology , Acetaldehyde/analysis , Adult , Female , Formaldehyde/analysis , Humans , Japan/epidemiology , Logistic Models , Male , Middle Aged , Organic Chemicals/analysis , Prevalence , Sick Building Syndrome/physiopathology
9.
Phys Rev Lett ; 93(15): 157601, 2004 Oct 08.
Article in English | MEDLINE | ID: mdl-15524941

ABSTRACT

Depth-controlled beta-NMR can be used to probe the magnetic properties of thin films and interfaces on a nanometer length scale. A 30 keV beam of highly spin-polarized 8Li+ ions was slowed down and implanted into a 50 nm film of Ag deposited on a SrTiO3 substrate. A novel high field beta-NMR spectrometer was used to observe two well resolved resonances which are attributed to Li occupying substitutional and octahedral interstitial sites in the Ag lattice. The temperature dependence of the Knight shifts and spin relaxation rates are consistent with the Korringa law for a simple metal, implying that the NMR of implanted 8Li reflects the spin suspectibility of bulk metallic silver.

10.
Mod Rheumatol ; 12(4): 311-7, 2002 Dec.
Article in English | MEDLINE | ID: mdl-24383998

ABSTRACT

Abstract To assess the frequency of pulmonary changes in patients with rheumatoid arthritis (RA), we evaluated a subject group (all outpatients with RA visiting the hospital during a period of three consecutive days) by plain chest radiographs (CRs) and high-resolution computed tomography (HRCT). The study population consisted of 186 patients (32 men, 154 women; mean age 59.8 years), including 6 smokers or exsmokers. Chest radiography was performed on all patients. Seventy (Group A) patients demonstrated abnormal findings and 116 (Group B) did not. HRCT scans were performed on 69 of Group A and 54 of Group B. HRCT demonstrated centrilobular micronodules (n = 29; 23.6%), septal lines (n = 24; 19.5%), subpleural curvilinear shadows (n = 24; 19.5%), bronchiectasis (n = 21; 17.1%), dependent opacity (n = 14; 11.4%), nodules (n = 12; 9.8%), and honeycombing (n = 11; 8.9%). Ten (34%) of the patients with centrilobular micronodules also had bronchiectasis. The most frequent disorder was broncho-bronchiolar disease. Contrary to the CRs finding of no abnormality, HRCT detected pulmonary pathological findings in 40 of 54 patients (74.1%). Pulmonary diseases may be frequently latent, and HRCT is useful in evaluating them in patients with RA.

11.
J Inherit Metab Dis ; 25(6): 525-6, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12555949

ABSTRACT

A homozygous recessive mutation, causing GM1-gangliosidosis in Shiba dogs, was identified as a deletion of C nucleotide 1668 in the gene for canine acid beta-galactosidase, which was a novel mutation in canine GM1-gangliosidosis.


Subject(s)
Dog Diseases/enzymology , Dog Diseases/genetics , Gangliosidosis, GM1/genetics , Gangliosidosis, GM1/veterinary , beta-Galactosidase/genetics , Animals , DNA, Complementary/genetics , Dogs , Reverse Transcriptase Polymerase Chain Reaction
12.
Am J Ophthalmol ; 132(2): 280-2, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11476704

ABSTRACT

PURPOSE: We present favorable results with amniotic membrane transplantation in a patient who developed fat adherence syndrome after retinal surgery. DESIGN: Interventional case report. METHODS: A 37-year-old man had diplopia resulting from hypotropia of the left eye after retinal detachment surgery. Removal of a previously implanted silicon sponge had little effect because of fibrous adhesion between the inferior rectus muscle and adjacent periorbital fat. We performed amniotic membrane transplantation combined with conventional extraocular muscle surgery. RESULTS: Postoperatively, supraduction of the left eye became almost full. The field of binocular vision was extended markedly by treatment, both in the primary position and with downward gaze. These improvements remained stable over 1 year of follow-up. CONCLUSION: Amniotic membrane transplantation appears to be effective for preventing regrowth of restrictive scar tissue in the fat adherence syndrome.


Subject(s)
Adipose Tissue/surgery , Amnion/transplantation , Oculomotor Muscles/surgery , Orbital Diseases/surgery , Postoperative Complications/surgery , Retinal Detachment/surgery , Adipose Tissue/pathology , Adult , Diplopia/etiology , Diplopia/surgery , Humans , Male , Ocular Motility Disorders/etiology , Ocular Motility Disorders/surgery , Orbital Diseases/etiology , Postoperative Complications/pathology , Syndrome , Tissue Adhesions/surgery , Vision, Binocular
14.
J Nutr Sci Vitaminol (Tokyo) ; 47(4): 311-5, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11767213

ABSTRACT

The purpose of the current study was to assess the involvement of the branched-chain amino acid leucine in the regulation of translation initiation in the liver and to compare the time course of leucine action on the translation initiation in the liver and skeletal muscle of rats. The phosphorylation of the eukaryotic initiation factor (eIF)4E-binding protein 1 (4E-BP1) frees eIF4E and stimulates protein synthesis by accelerating translation initiation. Phosphorylation of the 70-kDa ribosomal protein S6 kinase (S6K) is thought to be involved in regulating the synthesis of certain ribosomal proteins and other selected proteins with polypyrimidine clusters near the transcription start site. Food-deprived (18 h) male rats were orally administered 135 mg/100 g body weight L-leucine and sacrificed at 0, 1, 3, or 6 h after administration. The oral administration of leucine resulted in an enhanced phosphorylation of 4E-BP1 and S6K1 in both the liver and skeletal muscle. A time-dependent change in the phosphorylation state of 4E-BP1 and S6K1 was more acute in the skeletal muscle than in the liver and closely paralleled the changes in plasma leucine concentration. Our results indicate that the primary mediator in 4E-BP1 phosphorylation and S6K1 phosphorylation by the oral administration of leucine is an increase in the plasma concentration of leucine. Furthermore, our findings suggest differential sensitivity in the tissue response to oral administration of leucine.


Subject(s)
Carrier Proteins/physiology , Leucine/administration & dosage , Liver/physiology , Muscle, Skeletal/physiology , Phosphoproteins/physiology , Phosphotransferases/physiology , Ribosomal Protein S6 Kinases/physiology , Administration, Oral , Animals , Intracellular Signaling Peptides and Proteins , Male , Phosphorylation , Rats , Rats, Wistar , Time Factors
15.
Phys Rev Lett ; 84(7): 1407-10, 2000 Feb 14.
Article in English | MEDLINE | ID: mdl-11017529

ABSTRACT

At temperatures below 2.1 K, long-lived gaseous Rb atoms in glass cells have been generated with a simple method: irradiating the cells, containing 4He gas and Rb metal, with a cw laser. The obtained atomic Rb density ( approximately 10(8) cm(-3)) decreases with a 1/e time constant of about 10 s at 1.85 K. We have performed optical pumping of the Rb atoms and measured the longitudinal electronic spin relaxation time at 1.85 K as well. For processes (such as Rb-He collisions) which do not remove the atomic Rb from the vapor, this relaxation time is found to be about 60+/-15 s.

16.
Mol Med ; 4(5): 356-60, 1998 May.
Article in English | MEDLINE | ID: mdl-9642685

ABSTRACT

Collagen V plays a major regulatory role in the formation of heterotypic fibers of the dermis and cartilaginous tissues as well as in the assembly of extracellular matrix. The pN/pN mouse, which is defective in collagen V alpha 2 gene, exhibits skeletal abnormalities, skin fragility, and alterations in the collagen fiber organization, whereas the TSK/+ mouse, which is defective in fibrillin-1, the major component of microfibrils present in the extracellular matrix, develops cutaneous hyperplasia and autoimmunity. We have studied the role of collagen V in the formation of heterotypic collagen fibers in F1 mice, which are obtained by breeding pN/pN with TSK/+ mice. Our results show that F1 progeny neither develop cutaneous hyperplasia nor produce anti-topoisomerase I autoantibodies, unlike TSK/+ mice. The diameter of the collagen fibrils in the skin is also comparable to that found in control mice. Thus, the phenotypic changes observed in the TSK mouse could be reversed by genetic complementation with a collagen V-defective mouse.


Subject(s)
Alleles , Collagen/genetics , Mutagenesis, Site-Directed/genetics , Skin/pathology , Animals , Autoantibodies/blood , Collagen/analysis , DNA Topoisomerases, Type I/immunology , Hyperplasia/genetics , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Phenotype , Skin/chemistry , Skin/ultrastructure
17.
Neurology ; 49(3): 870-1, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9305356

ABSTRACT

The virus-associated hemophagocytic syndrome (VAHS) is a lymphoproliferative disorder induced by viral infection. The peripheral nervous system is rarely involved in this syndrome and, when reported, the involvement has been axonal in nature. This paper presents a case of Guillain-Barré syndrome accompanied by VAHS subsequent to Epstein-Barr virus infection. The patient's condition improved following treatment with intravenous immunoglobulin infusion and high-dose corticosteroids.


Subject(s)
Herpesviridae Infections/complications , Herpesvirus 4, Human , Lymphoproliferative Disorders/etiology , Polyradiculoneuropathy/etiology , Adrenal Cortex Hormones/therapeutic use , Aged , Bone Marrow/pathology , Histiocytosis/pathology , Humans , Immunoglobulins, Intravenous/therapeutic use , Lymphoproliferative Disorders/therapy , Male , Tumor Virus Infections/complications
19.
J Autoimmun ; 10(6): 505-17, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9451590

ABSTRACT

Tight-skin (TSK) mouse, the experimental model for scleroderma, develops cutaneous hyperplasia, cardiac hypertrophy, pulmonary emphysema and autoimmunity against scleroderma target autoantigens. The cutaneous hyperplasia is associated with the accumulation of microfibrils and elastic fibers in the middle and deep dermis. Fibrillin-1 (Fbn-1) is a major component of the 10-12 nm microfibrils found in the extracellular matrix. In this study we report the identification of a genetic marker in the Fbn-1 gene that can distinguish the mutant phenotype. TSK mice exhibit an unique polymorphism in the Fbn-1 gene. RNA analysis, PCR analysis and sequence determination of the mutant gene showed that the Fbn-1 gene polymorphism is due to intragenic duplication of a segment of the gene coding for 3.0 Kb of mRNA sequence (10 Kb of the genome). Histological analysis of skin samples from F1 progeny obtained by crossing TSK mice with JH-/-, RAG2-/- or vit/vit showed a significant correlation between the inheritance of the defective Fbn-1 gene and the development of cutaneous hyperplasia. Further, our results also show that in mice deficient in mature B cells inheriting the defective Fbn-1 gene, development of cutaneous hyperplasia is not abrogated. Thus, production of autoantibodies or the presence of mature B lymphocytes do not play an integral role in the pathogenesis of cutaneous hyperplasia.


Subject(s)
B-Lymphocytes/physiology , Microfilament Proteins/genetics , Skin/pathology , Amino Acid Sequence , Animals , B-Lymphocytes/cytology , B-Lymphocytes/immunology , Base Sequence , DNA/genetics , DNA Probes , Fibrillin-1 , Fibrillins , Genetic Markers , Genotype , Hyperplasia/genetics , Hyperplasia/immunology , Mice , Mice, Inbred Strains , Molecular Sequence Data , Mutation , Phenotype , Polymerase Chain Reaction , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length , RNA, Messenger/metabolism , Skin/immunology , Skin Diseases/genetics , Skin Diseases/immunology
20.
J Autoimmun ; 9(4): 473-83, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8864822

ABSTRACT

Several reports have implicated an association between the development of connective tissue disorders and exposure to silicone in breast implant patients. These connective tissue disorders include local or systemic scleroderma-like syndrome and have been characterized by fibrosis as well as the presence of circulating autoantibodies. Whether silicone does potentiate the development of a scleroderma-like syndrome is still to be defined. The purpose of the present study was to determine the effect of silicone on the tight skin (TSK/+) mouse which develops a scleroderma-like syndrome and on its normal pa/pa TSK/- littermate. Groups of six TSK and five of their normal pa/pa littermates were injected subcutaneously with low molecular weight silicone (LMW-PDMS), high molecular weight silicone gel (HMW-PDMS), incomplete Freunds' adjuvant (IFA) or Hank's balanced salt solution (HBSS) in the dorsal neck area and ventrally in the upper chest region. Serum was obtained prior to and 1 month after injection of silicone, IFA, or control HBSS. Antibody levels to bovine serum albumin (BSA), RNA polymerase (RNAP) and topoisomerase I were determined. Mice were then euthanized and strips of skin from the injection sites as well as samples of kidney and liver were studied histologically. No significant pathological changes were observed in TSK/- mice 1 month following injection with HBSS, LMW-PDMS or HMW-PDMS. Skin samples from TSK/+ mice which received LMW-PDMS showed hyperplasia of the dermis and peri-panniculus carnosus tissue and infiltrates of macrophages containing lipid-like vacuolated materials. Lipid vacuoles were observed throughout the deeper dermis as multiple loculated vacuoles. TSK mice which received HMW-PDMS showed similar thickening of the dermis and the peri-panniculus carnosus connective tissue. There were no significant differences in the histologic characteristics of the silicone-injected TSK/+ mice compared to those that received HBSS or IFA. No detectable changes in the kidney, spleen, or liver samples taken from TSK/+ or TSK/- mice injected with HBSS, IFA or silicone (LMW-PDMS, HMW-PDMS) preparations were noted. Baseline circulating antibody levels to BSA, RNAP and topoisomerase were significantly higher in TSK/+ mice compared to the control TSK/- littermates. Administration of silicone (LMW-PDMS or HMW-PDMS) did not significantly alter circulating antibody levels to BSA, RNAP and topoisomerase in either the TSK/+ or the TSK/- mice. The results of this study indicate that silicone administration does not potentiate the development of the scleroderma-syndrome characterized by skin lesions and presence of circulating antibodies in the TSK/+ model.


Subject(s)
Mice, Mutant Strains/immunology , Scleroderma, Systemic/chemically induced , Silicones/pharmacology , Animals , Autoantibodies/blood , Disease Models, Animal , Drug Synergism , Mice
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