51
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Study of Kondo effect in MgO-based magnetic tunnel junctions by electron tunnelling spectroscopy. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/200/5/052004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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52
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Measurement of |V{ub}| from inclusive charmless semileptonic B decays. PHYSICAL REVIEW LETTERS 2010; 104:021801. [PMID: 20366585 DOI: 10.1103/physrevlett.104.021801] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Indexed: 05/29/2023]
Abstract
We present the partial branching fraction for inclusive charmless semileptonic B decays and the corresponding value of the Cabibbo-Kobayashi-Maskawa matrix element |V{ub}|, using a multivariate analysis method to access approximately 90% of the B-->X{u}lnu phase space. This approach dramatically reduces the theoretical uncertainties from the b-quark mass and nonperturbative QCD compared to all previous inclusive measurements. The results are based on a sample of 657x10{6} BB[over ] pairs collected with the Belle detector. We find that DeltaB(B-->X{u}lnu;p(l){*B}>1.0 GeV/c)=1.963x(1+/-0.088{stat}+/-0.081{syst})x10{-3}. Corresponding values of |V{ub}| are extracted using several theoretical calculations.
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53
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Measurement of inclusive radiative B-meson decays with a photon energy threshold of 1.7 GeV. PHYSICAL REVIEW LETTERS 2009; 103:241801. [PMID: 20366195 DOI: 10.1103/physrevlett.103.241801] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Indexed: 05/29/2023]
Abstract
Using 605 fb(-1) of data collected at the Upsilon(4S) resonance we present a measurement of the inclusive radiative B-meson decay channel, B-->X(s)gamma. For the lower photon energy thresholds of 1.7, 1.8, 1.9, and 2.0 GeV, as defined in the rest frame of the B meson, we measure the partial branching fraction and the mean and variance of the photon energy spectrum. At the 1.7 GeV threshold we obtain the partial branching fraction BF(B-->X(s)}gamma)=(3.45+/-0.15+/-0.40)x10(-4), where the errors are statistical and systematic.
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54
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Measurement of the differential branching fraction and forward-backward asymmetry for B --> K(*)l+l-. PHYSICAL REVIEW LETTERS 2009; 103:171801. [PMID: 19905747 DOI: 10.1103/physrevlett.103.171801] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2009] [Indexed: 05/28/2023]
Abstract
We study B --> K(*)l+l- decays (l = e, mu) based on a data sample of 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, isospin asymmetry, K* polarization, and the forward-backward asymmetry (A(FB)) as functions of q2 = M(ll)(2)c2. The fitted A(FB) spectrum exceeds the standard model expectation by 2.7 standard deviations. The measured branching fractions are B(B --> K*l+l-) = (10.7(-1.0)(+1.1) +/- 0.9) x 10(-7) and B(B --> Kl+l-) = (4.8(-0.4)(+0.5) +/- 0.3) x 10(-7), where the first errors are statistical and the second are systematic, with the muon to electron ratios R(K*) = 0.83 +/- 0.17 +/- 0.08 and R(K) = 1.03 +/- 0.19 +/- 0.06.
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CCR5 is required for regulation of alloreactive T-cell responses to single class II MHC-mismatched murine cardiac grafts. Am J Transplant 2009; 9:2251-61. [PMID: 19656127 PMCID: PMC2760830 DOI: 10.1111/j.1600-6143.2009.02786.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effector CD4 T-cell response in wild-type C57BL/6 recipients of single class II MHC-disparate B6.H-2(bm12) cardiac allografts is restricted by CD4(+)CD25(+) regulatory T cells (Tregs) resulting in long-term allograft survival. To investigate the role chemokine receptors might play in Treg function, this study tested the requirement for CCR5 on Tregs to suppress the alloimmune response in C57BL/6 recipients of B6.H-2(bm12) cardiac allografts. In contrast to the long-term survival of B6.H-2(bm12) allografts in wild-type recipients (>100 days), the allografts were acutely rejected within 25 days in CCR5(-/-) recipients with intense infiltration of CD4 T cells. Numbers and duration of donor-reactive CD4 T cells producing IFN-gamma and IL-4 were markedly increased in spleens of B6.CCR5(-/-) versus wild-type recipients. Wild-type and B6.CCR5(-/-) mice had equivalent numbers of splenic FoxP3(+) Tregs before and following transplantation, and these Tregs were equivalently suppressive in vitro. However, diminished numbers of FoxP3(+) Tregs infiltrated B6.H-2(bm12) allografts in B6.CCR5(-/-) recipients. Adoptive transfer of wild-type, but not CCR5-deficient, CD4(+)CD25(+) Tregs to CCR5(-/-) recipients restored long-term survival of B6.H-2(bm12) cardiac grafts. Collectively, these results indicate that CCR5 expression is required for the regulatory functions of Tregs that restrict alloreactive CD4 T-cell responses to single class II MHC-mismatched cardiac allografts.
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POSTOPERATIVE CHANGES OF SPERM CHROMATIN HETEROGENEITY, USING ACRIDINE ORANGE STAINING, IN VARICOCELE PATIENTS. ACTA ACUST UNITED AC 2009; 52:223-6. [PMID: 16574605 DOI: 10.1080/01485010500428397] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The aim of this study was to evaluate postoperative changes in sperm chromatin heterogeneity in varicocele patients. In 15 infertile patients with varicocele, sperm parameters including concentration, motility, and morphology were evaluated before and after surgical correction of varicocele. Sperm motion analysis using computer-assisted semen analyzer (CASA) was also performed. To analyze the sperm nuclear proteins, the acridine orange staining method was used. On semen analysis, sperm concentration and motility significantly increased after surgery (p = 0.002, p = 0.003, respectively), although sperm morphology was unaltered postoperatively. CASA parameters, including velocity, linearity, amplitude of lateral head displacement and beat cross frequency were unaltered postoperatively. On the other hand, acridine orange staining significantly increased postoperatively (p = 0.002). Varicocele influences the sperm chromatin condition, as well as sperm concentration and motility.
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Abstract: P237 TELMISARTAN PROTECTS FROM ENDOTHELIAL CELL DAMAGE BY IMPROVING MITOCHONDRIAL FUNCTION THROUGH PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR-Γ INDEPENDENT PATHWAYS. ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)70302-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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58
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Large voltage-induced magnetic anisotropy change in a few atomic layers of iron. NATURE NANOTECHNOLOGY 2009; 4:158-161. [PMID: 19265844 DOI: 10.1038/nnano.2008.406] [Citation(s) in RCA: 256] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Accepted: 12/09/2008] [Indexed: 05/27/2023]
Abstract
In the field of spintronics, researchers have manipulated magnetization using spin-polarized currents. Another option is to use a voltage-induced symmetry change in a ferromagnetic material to cause changes in magnetization or in magnetic anisotropy. However, a significant improvement in efficiency is needed before this approach can be used in memory devices with ultralow power consumption. Here, we show that a relatively small electric field (less than 100 mV nm(-1)) can cause a large change (approximately 40%) in the magnetic anisotropy of a bcc Fe(001)/MgO(001) junction. The effect is tentatively attributed to the change in the relative occupation of 3d orbitals of Fe atoms adjacent to the MgO barrier. Simulations confirm that voltage-controlled magnetization switching in magnetic tunnel junctions is possible using the anisotropy change demonstrated here, which could be of use in the development of low-power logic devices and non-volatile memory cells.
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Comparative study of polyvinylidene fluoride and PES flat membranes in submerged MBRs to treat domestic wastewater. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2009; 59:399-405. [PMID: 19213993 DOI: 10.2166/wst.2009.849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Two kinds of membranes, polyvinylidene fluoride (PVDF) and polyethersulfone (PES), were used in submerged flat membrane bioreactors (MBRs) to treat domestic wastewater in this study. The MBRs ran under the same reactor structure, the same membrane pore size of 0.45 mICROm and the same anoxic/ oxic (A/O) process. The experimental results showed that: (1) With the influent of BOD(5) 200-500 mg/L and COD(Cr) 400-1,000 mg/L, PVDF MBR achieved the removal efficiencies of BOD(5) 96-98% and COD(Cr) 89-98%, and those were 97-99% and 93-97% in PES MBR. The interceptive efficiency of PES membrane to BOD(5) and COD(Cr) was superior to PVDF membrane. (2) The removal efficiencies of TN and NH(3)-N in two MBRs exhibited good results which were greater than 85%. The removal efficiencies of TP were greater than 80% in both MBRs. (3) MLSS concentration changed from 2,000 mg/L to 7,000 mg/L during the experiment. PES membrane was not washed and the membrane flux was steady. However, the flux of PVDF one decreased quickly and was washed for twice. It meant that PES membrane had fine capability than PVDF one.
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60
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Somatic and psychological factors related to the body mass index of patients with anorexia nervosa. Eat Weight Disord 2008; 13:198-204. [PMID: 19169076 DOI: 10.1007/bf03327507] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE The aim of this study was to examine somatic and psychological factors related to the body mass index (BMI) of anorexia nervosa (AN) patients. METHOD The analysis was of 24 hospitalized AN patients from the day after admission to the 4th day. The somatic factors analyzed were duration of AN, daily food intake, eating regulatory substances in blood (acylated ghrelin, desacyl ghrelin, leptin), serum cortisol, insulin and estimated creatinine clearance (CCr). The psychological factors analyzed were depression, anxiety, Eating Disorder Inventory (EDI), and hunger/fullness feeling. Measurement of BMI and collection of blood samples were done on the morning after hospitalization. Statistical analysis was by multiple linear regression analysis. RESULTS BMI showed a reverse correlation with desacyl ghrelin (beta=-0.486, p=0.015) and maturity fears (beta=-0.375, p=0.046), but was not associated with any other factor by multiple regression analysis. CONCLUSION The results suggest that desacyl ghrelin and maturity fears play important roles in the prolonged malnutrition state seen in AN patients.
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61
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Charged particle activation analysis at RIKEN: Past, present and future. J Radioanal Nucl Chem 2008. [DOI: 10.1007/s10967-008-0301-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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62
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Measurement of branching fractions, isospin, and CP-violating asymmetries for exclusive b-->dgamma modes. PHYSICAL REVIEW LETTERS 2008; 101:111801. [PMID: 18851272 DOI: 10.1103/physrevlett.101.111801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Indexed: 05/26/2023]
Abstract
We report new measurements of the decays B+-->rho+gamma, B0-->rho0gamma, and B0-->omegagamma using a data sample of 657x10(6) B meson pairs accumulated with the Belle detector at the KEKB e+e- collider. We measure branching fractions B(B+-->rho+gamma)=(8.7_-2.7-1.1;+2.9+0.9)x10(-7), B(B0-->rho0gamma)=(7.8_-1.6-1.0;+1.7+0.9)x10(-7), and B(B0-->omegagamma)=(4.0_-1.7;+1.9+/-1.3)x10(-7). We also report the isospin asymmetry Delta(rhogamma)=-0.48_-0.19-0.09;+0.21+0.08 and the first measurement of the direct CP-violating asymmetry ACP(B+-->rho+gamma)=-0.11+/-0.32+/-0.09, where the first and second errors are statistical and systematic, respectively.
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63
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X-ray crystal structure analyses of methionine γ-lyase 1 and 2 from Entamoeba histolytica. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308085899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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64
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Clinical value of second- and third-generation assays of anti-cyclic citrullinated peptide antibodies in rheumatoid arthritis. Ann Rheum Dis 2008; 67:1059-60. [PMID: 18556455 DOI: 10.1136/ard.2007.082826] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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65
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Donor-reactive CD8 memory T cells infiltrate cardiac allografts within 24-h posttransplant in naive recipients. Am J Transplant 2008; 8:1652-61. [PMID: 18557725 PMCID: PMC2625311 DOI: 10.1111/j.1600-6143.2008.02302.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Normal immune responses stimulated by pathogenic and environmental antigens generate memory T cells that react with donor antigens and no currently used immunosuppressive drug completely inhibits memory T-cell function. While donor-reactive memory T cells clearly compromise graft outcomes, mechanisms utilized by memory T cells to promote rejection are largely unknown. In this study, we investigated how early endogenous memory cells infiltrate and express effector function in cardiac allografts. Endogenous CD8 memory T cells in nonsensitized recipients distinguish syngeneic versus allogeneic cardiac allografts within 24 h of reperfusion. CD8-dependent production of IFN-gamma and CXCL9/Mig was observed 24 to 72 h posttransplant in allografts but not isografts. CXCL9 was produced by donor cells in response to IFN-gamma made by recipient CD8 T cells reactive to donor class I major histocompatibility complex (MHC) molecules. Activated CD8 T cells were detected in allografts at least 3 days before donor-specific effector T cells producing IFN-gamma were detected in the recipient spleen. Early inflammation mediated by donor-reactive CD8 memory T cells greatly enhanced primed effector T-cell infiltration into allografts. These results suggest that strategies for optimal inhibition of alloimmunity should include neutralization of infiltrating CD8 memory T cells within a very narrow window after transplantation.
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66
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Observation of a resonancelike structure in the pi +- psi' mass distribution in exclusive B-->Kpi +- psi' decays. PHYSICAL REVIEW LETTERS 2008; 100:142001. [PMID: 18518023 DOI: 10.1103/physrevlett.100.142001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Indexed: 05/26/2023]
Abstract
A distinct peak is observed in the pi +/- psi' invariant mass distribution near 4.43 GeV in B-->K pi +/- psi' decays. A fit using a Breit-Wigner resonance shape yields a peak mass and width of M=4433+/-4(stat)+/-2(syst) MeV and Gamma=45-13+18(stat)-13+30(syst) MeV. The product branching fraction is determined to be B(B 0-->K -/+Z+/-(4430)) x B(Z+/-(4430)-->pi+/-psi')=(4.1+/-1.0(stat)+/-1.4(syst)) x 10(-5), where Z+/-(4430) is used to denote the observed structure. The statistical significance of the observed peak is 6.5 sigma. These results are obtained from a 605 fb(-1) data sample that contains 657 x 10(6) BB pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider.
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67
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Observation of B_(s)(0)-->phigamma and search for B_(s)(0)-->gammagamma decays at Belle. PHYSICAL REVIEW LETTERS 2008; 100:121801. [PMID: 18517854 DOI: 10.1103/physrevlett.100.121801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Indexed: 05/26/2023]
Abstract
We search for the radiative penguin decays B_{s}{0}-->varphigamma and B_{s}{0}-->gammagamma in a 23.6 fb{-1} data sample collected at the Upsilon(5S) resonance with the Belle detector at the KEKB e{+}e{-} asymmetric-energy collider. We observe for the first time a radiative penguin decay of the B_{s}{0} meson in the B_{s}{0}-->varphigamma mode and we measure B(B_{s}{0}-->varphigamma)=(57_{-15}{+18}(stat)-11+12(syst))x10{-6}. No significant B_{s}{0}-->gammagamma signal is observed and we set a 90% confidence level upper limit of B(B_{s}{0}-->gammagamma)<8.7x10{-6}.
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68
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Measurement of time-dependent CP-violating parameters in B(0)-->K_(S)(0)K_(S)(0) decays. PHYSICAL REVIEW LETTERS 2008; 100:121601. [PMID: 18517853 DOI: 10.1103/physrevlett.100.121601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Indexed: 05/26/2023]
Abstract
We report a measurement of the CP-violating parameters in B;{0}-->K_{S}{0}K_{S}{0} decays based on a data sample of 657x10{6} BB[over ] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e;{+}e{-} collider. In this Letter, one neutral B meson is fully reconstructed in the B;{0}-->K_{S}{0}K_{S}{0} decay mode, and the flavor of the accompanying B meson is identified by its decay products. The CP-violating parameters are measured from the asymmetry in the distributions of the proper-time interval between the two B decays: S_K_{S}{0}K_{S}{0}}=-0.38_{-0.77}{+0.69}(stat)+/-0.09(syst) and A_{K_{S}{0}K_{S}{0}}=-0.38+/-0.38(stat)+/-0.05(syst).
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69
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Observation of a new DsJ meson in B+-->D0D0K+ decays. PHYSICAL REVIEW LETTERS 2008; 100:092001. [PMID: 18352700 DOI: 10.1103/physrevlett.100.092001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Indexed: 05/26/2023]
Abstract
We report the observation of a new DsJ meson produced in B+-->D0DsJ-->D0D0K+. This state has a mass of M=2708+/-9(-10)(+11) MeV/c2, a width Gamma=108+/-23(-31)(+36) MeV/c2 and a 1- spin-parity. The statistical significance of this observation is 8.4 sigma. The results are based on an analysis of 449 x 10(6) BB events collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.
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70
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Abstract
Increasing detection of acute humoral rejection (AHR) of renal allografts has generated the need for appropriate animal models to investigate underlying mechanisms. Murine recipients lacking the chemokine receptor CCR5 reject cardiac allografts with marked C3d deposition in the parenchymal capillaries and high serum donor-reactive antibody titers, features consistent with AHR. The rejection of MHC-mismatched renal allografts from A/J (H-2(a)) donors by B6.CCR5(-/-) (H-2(b)) recipients was investigated. A/J renal allografts survived longer than 100 days in wild-type C57BL/6 recipients with normal blood creatinine levels (28 +/- 7 micromol/L). All CCR5(-/-) recipients rejected renal allografts within 21 days posttransplant (mean 13.3 +/- 4 days) with elevated creatinine (90 +/- 31 micromol/L). The rejected allografts had neutrophil and macrophage margination and diffuse C3d deposition in peritubular capillaries, interstitial hemorrhage and edema, and glomerular fibrin deposition. Circulating donor-reactive antibody titers were 40-fold higher in B6.CCR5(-/-) versus wild-type recipients. Depletion of recipient CD8 T cells did not circumvent rejection of the renal allografts by CCR5-deficient recipients. In contrast, microMT(-/-)/CCR5(-/-) recipients, incapable of producing antibody, did not reject most renal allografts. Collectively, these results indicate the rapid rejection of renal allografts in CCR5(-/-) recipients with many histopathologic features observed during AHR of human renal allografts.
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Abstract
The intestinal parasite Entamoeba histolytica is one of the first protists for which a draft genome sequence has been published. Although the genome is still incomplete, it is unlikely that many genes are missing from the list of those already identified. In this chapter we summarise the features of the genome as they are currently understood and provide previously unpublished analyses of many of the genes.
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72
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Time-dependent CP-violating asymmetry in B0-->rho0gamma decays. PHYSICAL REVIEW LETTERS 2008; 100:021602. [PMID: 18232853 DOI: 10.1103/physrevlett.100.021602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Indexed: 05/25/2023]
Abstract
We report the first measurement of CP-violation parameters in B0-->rho0gamma decays based on a data sample of 657x10(6)BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain the time-dependent and direct CP-violating parameters, Srho0gamma=-0.83+/-0.65(stat)+/-0.18(syst) and Arho0gamma=-0.44+/-0.49(stat)+/-0.14(syst), respectively.
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73
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Search for the CP-violating decays Upsilon(4S)-->B0B0-->J/psiKS0+J/psi(etac)KS0. PHYSICAL REVIEW LETTERS 2007; 99:211601. [PMID: 18233206 DOI: 10.1103/physrevlett.99.211601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Indexed: 05/25/2023]
Abstract
We report the first search for CP-violating decays of the Upsilon(4S) using a data sample that contains 535 x 10(6) Upsilon(4S) mesons with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. A partial reconstruction technique is employed to enhance the signal sensitivity. No significant signals were observed. We obtain an upper limit of 4 x 10(-7) at the 90% confidence level for the branching fractions of the CP violating modes, Upsilon(4S)-->B(0)B(0)-->J/psiK(S)(0)+J/psi(eta(c))K(S)(0). Extrapolating the result, we find that an observation with 5sigma significance is expected with a 30 ab(-1) data sample, which is within the reach of a future super B factory.
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74
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Observation of B(0)-->D(*-)tau(+)nu(tau) decay at Belle. PHYSICAL REVIEW LETTERS 2007; 99:191807. [PMID: 18233068 DOI: 10.1103/physrevlett.99.191807] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Indexed: 05/25/2023]
Abstract
We report an observation of the decay B{0}-->D{*-}tau{+}nu{tau} in a data sample containing 535x10{6} BB pairs collected with the Belle detector at the KEKB asymmetric-energy e{+}e{-} collider. We find a signal with a significance of 5.2sigma and measure the branching fraction B(B{0}-->D{*-}tau{+}nu{tau})=(2.02{-0.37}{+0.40}(stat)+/-0.37(syst))%. This is the first observation of an exclusive B decay with a b-->ctaunu{tau} transition.
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Abstract
We observe evidence for D(0)-D(0) mixing by measuring the difference in the apparent lifetime when a D(0) meson decays to the CP eigenstates K(+)K(-) and pi(+)pi(-) and when it decays to the final state K(-)pi(+). We find the relative difference of the lifetimes y(CP) to be [1.31+/-0.32(stat)+/-0.25(syst)]%, 3.2 standard deviations from zero. We also search for a CP asymmetry between D(0) and D(0) decays; no evidence for CP violation is found. These results are based on 540 fb(-1) of data recorded by the Belle detector at the KEKB e(+)e(-) collider.
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76
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Observation of direct CP violation in B0 --> pi+pi- decays and model-independent constraints on the quark-mixing angle phi2. PHYSICAL REVIEW LETTERS 2007; 98:211801. [PMID: 17677763 DOI: 10.1103/physrevlett.98.211801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2006] [Revised: 02/14/2007] [Indexed: 05/16/2023]
Abstract
We report a new measurement of the time-dependent CP-violating parameters in B(0)-->pi(+)pi(-) decays with 535 x 10(6) BB pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider operating at the Upsilon(4S) resonance. We find 1464+/-65 B(0)-->pi(+)pi(-) events and measure the CP-violating parameters S(pipi)=-0.61+/-0.10(stat)+/-0.04(syst) and A(pipi)=+0.55+/-0.08(stat)+/-0.05(syst). We observe large direct CP violation with a significance greater than 5 standard deviations for any S(pipi) value. Using isospin relations, we measure the Cabibbo-Kobayashi-Maskawa quark-mixing matrix angle phi(2)=(97+/-11) degrees for the solution consistent with the standard model and exclude the range 11 degrees <phi(2)<79 degrees at the 95% confidence level.
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77
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Observation of B decays to two kaons. PHYSICAL REVIEW LETTERS 2007; 98:181804. [PMID: 17501563 DOI: 10.1103/physrevlett.98.181804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2006] [Revised: 03/15/2007] [Indexed: 05/15/2023]
Abstract
Using 449x10(6) BB[over ] pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider, we observe clear signals for B(+)-->K[over ](0)K(+) and B(0)-->K[over ](0)K(0) decays with 5.3sigma and 6.0sigma significance, respectively. We measure the branching fractions B(B(+)-->K[over ](0)K(+))=(1.22(-0.28-0.16)(+0.32+0.13))x10(-6) and B(B(0)-->K[over ](0)K(0))=(0.87(-0.20)(+0.25)+/-0.09)x10(-6), and partial-rate asymmetries A(CP)(B(+)-->K[over ](0)K(+))=0.13(-0.24)(+0.23)+/-0.02 and A(CP)(B(0)-->K[over ](0)K(0))=-0.58(-0.66)(+0.73)+/-0.04. From a simultaneous fit, we also obtain B(B(+)-->K(0)pi(+))=(22.8(-0.7)(+0.8)+/-1.3)x10(-6) and A(CP)(B(+)-->K(0)pi(+))=0.03+/-0.03+/-0.01. The first and second error in the branching fractions and the partial-rate asymmetries are statistical and systematic, respectively. No signal is observed for B(0)-->K(+)K(-) decays, and for this branching fraction, we set an upper limit of 4.1x10(-7) at the 90% confidence level.
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78
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Search for invisible decay of the Upsilon(1S). PHYSICAL REVIEW LETTERS 2007; 98:132001. [PMID: 17501190 DOI: 10.1103/physrevlett.98.132001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2006] [Indexed: 05/15/2023]
Abstract
We report results of a search for the invisible decay of the Upsilon(1S) via the Upsilon(3S)-->pi+ pi- Upsilon(1S) transition using a data sample of 2.9 fb-1 at the Upsilon(3S) resonance. The data were collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. No signal is found, and an upper limit for the branching fraction at the 90% confidence level is determined to be B(Upsilon(1S)-->invisible)<2.5 x 10(-3).
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79
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Measurement of inclusive Ds, D0, and J/psi rates and determination of the Bs(*)Bs(*) production fraction in bb Events at the Upsilon(5S) resonance. PHYSICAL REVIEW LETTERS 2007; 98:052001. [PMID: 17358846 DOI: 10.1103/physrevlett.98.052001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2006] [Indexed: 05/14/2023]
Abstract
The inclusive production of D(s), D(0), and J/psi mesons is studied using a 1.86 fb(-1) data sample collected on the Upsilon(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The number of bb events in this Upsilon(5S) data sample is determined. We measure the branching fractions B(Upsilon(5S)-->D(s)X)/2=(23.6+/-1.2+/-3.6)%, B(Upsilon(5S)-->D(0)X)/2=(53.8+/-2.0+/-3.4)%, and B(Upsilon(5S)-->J/psiX)/2=(1.030+/-0.080+/-0.067)%. From the D(s) and D(0) inclusive branching fractions the ratio f(s)=(18.0+/-1.3+/-3.2)% of B(s)(*)B(s)(*) to the total bb quark pair production at the Upsilon(5S) energy is obtained in a model-dependent way.
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80
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Observation of time-dependent CP violation in B0 --> eta'K0 decays and improved measurements of CP asymmetries in B0 --> phiK0, KS0KS0KS0 and B0 --> J/psiK0 decays. PHYSICAL REVIEW LETTERS 2007; 98:031802. [PMID: 17358677 DOI: 10.1103/physrevlett.98.031802] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Indexed: 05/14/2023]
Abstract
We present improved measurements of CP-violation parameters in B(0) --> phiK(0), eta(')K(0), KS(0)KS(0)KS(0) decays based on a sample of 535 x 10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. We obtain sin2phi1(eff)=+0.64+/-0.10(stat)+/-0.04(syst) for B(0) --> eta(')K(0), +0.50+/-0.21(stat)+/-0.06(syst) for B(0) --> phiK(0), and +0.30+/-0.32(stat)+/-0.08(syst) for B(0) --> KS(0)KS(0)KS(0) decays. We have observed CP violation in the B(0) --> eta(')K(0) decay with a significance of 5.6 standard deviations. We also perform an improved measurement of CP asymmetries in B(0) --> J/psiK(0) decays and obtain sin2phi1=+0.642+/-0.031(stat)+/-0.017(syst).
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81
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Evidence of the purely leptonic decay B- --> tau- nu(tau). PHYSICAL REVIEW LETTERS 2006; 97:251802. [PMID: 17280341 DOI: 10.1103/physrevlett.97.251802] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2006] [Revised: 10/18/2006] [Indexed: 05/13/2023]
Abstract
We present the first evidence of the decay B- --> tau- nu(tau), using 414 fb(-1) of data collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+ e- collider. Events are tagged by fully reconstructing one of the B mesons in hadronic modes. We detect the signal with a significance of 3.5 standard deviations including systematics and measure the branching fraction to be B(B- --> tau- nu(tau)) = (1.79(-0.49) +0.56(stat)(-0.51) +0.46(syst)) x 10(-4). This implies that fB = 0.229(-0.031) +0.036(stat)(-0.037) +0.034(syst) GeV and is the first direct measurement of this quantity.
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82
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Observation of new states decaying into Lambda(c)(+)Kappa(-)pi(+) and Lambda(c)(+)Kappa(0)/(s)pi(-). PHYSICAL REVIEW LETTERS 2006; 97:162001. [PMID: 17155385 DOI: 10.1103/physrevlett.97.162001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Indexed: 05/12/2023]
Abstract
We report the first observation of two charmed strange baryons that decay into Lambda(c)(+)Kappa(-)pi(+). The broader of the two states is measured to have a mass of 2978.5+/-2.1+/-2.0 MeV/c2 and a width of 43.5+/-7.5+/-7.0 MeV/c2. The mass and width of the narrow state are measured to be 3076.7+/-0.9+/-0.5 MeV/c;{2} and 6.2+/-1.2+/-0.8 MeV/c2, respectively. We also perform a search for the isospin partner states that decay into Lambda(c)(+)Kappa(0)/(s)pi(-) and observe a significant signal at the mass of 3082.8+/-1.8+/-1.5 MeV/c2. The data used for this analysis were accumulated at or near the Upsilon(4S) resonance, using the Belle detector at the e+ e- asymmetric-energy collider KEKB. The integrated luminosity of the data sample used is 461.5 fb(-1).
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83
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Abstract
In many experimental models, heart, pancreas and kidney allografts are accepted long-term following costimulation-targeting therapies, whereas skin, lung and intestine resist the induction of tolerance under the same regimens. We noted that a common feature of the resistant organs is their constant exposure to commensal microbes and hypothesized that these microorganisms may stimulate Toll-like receptors (TLRs), promote alloresponses and prevent tolerance induction. This hypothesis prompts the predictions that TLR engagement at the time of transplantation should avert tolerance to heart allografts in animals treated with costimulation-targeting therapies, whereas inhibition of TLR signaling should promote tolerance to skin allografts under the same conditions. Indeed, engagement of a single TLR was sufficient to prevent anti-CD154-mediated long-term cardiac allograft acceptance and correlated with abolished intragraft recruitment of CD4+/FoxP3+ regulatory T cells and the development of linked-suppression. Conversely, a lack of donor and recipient MyD88-dependent signaling led to successful skin allograft acceptance in anti-CD154-treated animals. Thus, the status of TLR signaling contributes to the resistance versus susceptibility of organs to transplantation tolerance.
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84
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Measurement of the quark mixing parameter cos2phi1 using time-dependent Dalitz analysis of B0 -->D[KS(0)pi + pi-]h0. PHYSICAL REVIEW LETTERS 2006; 97:081801. [PMID: 17026290 DOI: 10.1103/physrevlett.97.081801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Indexed: 05/12/2023]
Abstract
We present a measurement of the angle phi1 of the Cabibbo-Kobayashi-Maskawa unitarity triangle using a time-dependent Dalitz analysis of D-->KS(0)pi + pi- decays produced in neutral B meson decay to a neutral D meson and a light meson (B0-->D*h0). The method allows a direct extraction of 2phi1 and, therefore, helps to resolve the ambiguity between 2phi1 and pi-2phi1 in the measurement of sin2phi1. We obtain sin2phi1= 0.78 +/- 0.44 +/- 0.22 and cos2varphi1 = 1.87(-0.53-0.32)(+0.40 + 0.22). The sign of cos2phi1 is determined to be positive at 98.3% C.L.
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85
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86
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Synthesis of [11C] platelet-activating factor (PAF) analogs for in vivo imaging of PAF receptors. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580331006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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87
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Measurement of forward-backward asymmetry and Wilson coefficients in B --> K*l+l-. PHYSICAL REVIEW LETTERS 2006; 96:251801. [PMID: 16907294 DOI: 10.1103/physrevlett.96.251801] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2006] [Indexed: 05/11/2023]
Abstract
We report the first measurement of the forward-backward asymmetry and the ratios of Wilson coefficients and in A9/A7 and A10/A7 in B --> K*l+l-, where l represents an electron or a muon. We find evidence for the forward-backward asymmetry with a significance of 3.4sigma. The results are obtained from a data sample containing 386 x 10(6) BB pairs that were collected on the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.
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88
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Observation of b-->dgamma and determination of /Vtd/Vts/. PHYSICAL REVIEW LETTERS 2006; 96:221601. [PMID: 16803300 DOI: 10.1103/physrevlett.96.221601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2006] [Indexed: 05/10/2023]
Abstract
We report the observation of the flavor-changing neutral current process b-->dgamma using a sample of 386 x 106 B meson pairs accumulated by the Belle detector at the KEKB e+e- collider. We measure branching fractions for the exclusive modes B--->rho-gamma, B0rho0gamma, and B0omegagamma. Assuming that these three modes are related by isospin, we find B(B-->(rho,gamma)gamma)=[Formula: See Text] with a significance of 5.1sigma. This result is used to determine the ratio of Cabibbo-Kobayashi-Maskawa matrix elements /Vtd/Vts/ to be [Formula: See Text].
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89
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Abstract
OBJECTIVE Anorexia nervosa (AN) patients were surveyed to determine which disease factors were related to AN influenced renal dysfunction. METHODS Data were from forty-five AN patients hospitalized in our department between 1995 and 2002. The patients were classified into three groups based on the type of anorexia: restricting (n=18), self-induced vomiting (n=13), and laxative abuse (n=14). Twenty-four hour-creatinine clearance (Ccr) was calculated within two weeks of hospitalization for comparison among the three groups. RESULTS The Ccr level of the laxative abuse group was significantly lower than that of the restricting group (65.8+/-31.4 ml/min vs restricting type: 104+/-23.3 ml/min, p=0.002). The laxative abuse group had a significantly longer duration of illness than the restricting group (p<0.0001). Multiple regression analysis revealed the duration of illness to be a risk factor for renal function deterioration in AN patients (r=0.580, p<0.001). DISCUSSION Renal function should be carefully followed during the treatment of AN patients with a long duration of illness, especially those with long-term laxative abuse.
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90
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Psychopathological features of patients with prolonged anorexia nervosa as assessed by the Minnesota Multiphasic Personality Inventory. Eat Weight Disord 2006; 11:59-65. [PMID: 16809976 DOI: 10.1007/bf03327752] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE The duration of illness is quite long in some anorexia nervosa (AN) patients. In the present study, we investigated the psychopathological features of patients with prolonged AN as assessed by the Minnesota Multiphasic Personality Inventory-1 (MMPI-1). METHODS Fifty-five AN patients completed the MMPI-1 on admission to Kyushu University Hospital from 1999 to 2002. The patients were divided into three groups on the basis of their illness duration: a short-term group, less than 5 years of illness duration (n=31); a middle-term group, from 5 to 10 years (n=14); and a prolonged group, 10 years or more (n=10). RESULTS The prolonged group scored significantly higher on the MPPI-1 scales of hysteria (Hy), low back pain (Lb) and family conflict than the short-term group. DISCUSSION AN patients whose illness duration was prolonged characteristically had more hysteria with family conflict. This should be considered in their treatment.
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91
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Improved constraints on D0-D0 mixing in D0 --> K+ pi- decays from the Belle detector. PHYSICAL REVIEW LETTERS 2006; 96:151801. [PMID: 16712147 DOI: 10.1103/physrevlett.96.151801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2006] [Indexed: 05/09/2023]
Abstract
We report the results of a search for D0-D0 mixing in D0 --> K+ pi- decays based on 400 fb(-1) of data accumulated by the Belle detector at KEKB. Both assuming CP conservation and allowing for CP violation, we fit the decay-time distribution for the mixing parameters x and y, as well as for the parameter R(D), the ratio of doubly Cabibbo-suppressed decays to Cabibbo-favored decays. The 95% confidence level region in the (x'2,y') plane is obtained using a frequentist method. Assuming CP conservation, we find x'2 < 0.72 x 10(-3) and -9.9 x 10(-3) < y' < 6.8 x 10(-3) at the 95% confidence level; these are the most stringent constraints on the mixing parameters to date. The no-mixing point (0,0) has a confidence level of 3.9%. Assuming no mixing, we measure R(D) = (0.377 +/- 0.008 +/- 0.005)%.
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92
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Quantum oscillation of the tunneling conductance in fully epitaxial double barrier magnetic tunnel junctions. PHYSICAL REVIEW LETTERS 2006; 96:027208. [PMID: 16486629 DOI: 10.1103/physrevlett.96.027208] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2005] [Indexed: 05/06/2023]
Abstract
We investigated spin-dependent tunneling conductance properties in fully epitaxial double MgO barrier magnetic tunnel junctions with layered nanoscale Fe islands as a middle layer. Clear oscillations of the tunneling conductance were observed as a function of the bias voltage. The oscillation, which depends on the middle layer thickness and the magnetization configuration, is interpreted by the modulation of tunneling conductance due to the spin-polarized quantum well states created in the middle Fe layer. This first observation of the quantum size effect in the fully epitaxial double barrier magnetic tunnel junction indicates great potential for the development of the spin-dependent resonant tunneling effect in coherent tunneling regime.
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93
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Abstract
Fifteen patients 60 to 80 years old (a mean of 72 years) with hormone-refractory prostate cancer were treated with low dose prednisolone. All patients had previously undergone hormone therapy. Prostate specific antigen (PSA) values decreased in 11 cases (73%), of which 4 had PSA decreases of 50% or greater. Serum levels of DHEAS significantly decreased at 4 and 8 weeks after treatment (both intervals were p < 0.05 vs pretreatment). Of 8 patients with bone metastasis evaluation, 2 (25%) showed improvement of the lesion. In 5 patients (33%), relief of pain was observed one month after starting prednisolone. The one-year survival rate was 58%. The side effects were mild and manageable in an outpatient clinic.
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94
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Determination of /Vub/ from measurements of the inclusive charmless semileptonic partial rates of B mesons using full reconstruction tags. PHYSICAL REVIEW LETTERS 2005; 95:241801. [PMID: 16384368 DOI: 10.1103/physrevlett.95.241801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2005] [Indexed: 05/05/2023]
Abstract
We present a measurement of the Cabibbo-Kobayashi-Maskawa matrix element /Vub/, based on 253 fb(-1) of data collected by the Belle detector at the KEKB e+ e- asymmetric collider. Events are tagged by fully reconstructing one of the B mesons, produced in pairs from Gamma(4S). The signal for b --> u semileptonic decay is distinguished from the b --> c background using the hadronic mass Mx, the leptonic invariant mass squared q2 and the variable P+ [triple bond] Ex - /px/. The results are obtained for events with p(l)* > or = 1 GeV/c, in three kinematic regions (1) Mx < 1.7 GeV/c2, (2) Mx < 1.7 GeV/c2 combined with q2 > 8 GeV2/c2, and by (3) P+ < 0.66 GeV/c. The matrix element /Vub/ is found to be (4.09 +/- 0.19 +/- 0.20(+0.14) -0.15 +/- 0.18) x 10(-3), where the errors are statistical, systematic including Monte Carlo modeling, theoretical, and from shape function parameter determination, respectively.
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95
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Measurements of B decays to two kaons. PHYSICAL REVIEW LETTERS 2005; 95:231802. [PMID: 16384296 DOI: 10.1103/physrevlett.95.231802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2005] [Indexed: 05/05/2023]
Abstract
We report measurements of B meson decays to two kaons using 253 fb(-1) of data collected with the Belle detector at the KEKB energy-asymmetric e+ e- collider. We find evidence for signals in B+ --> K0 K+ and B0 --> K0 K0 with significances of 3.0sigma and 3.5sigma, respectively. (Charge-conjugate modes are included.) The corresponding branching fractions are measured to be [symbol: see text](B+ --> K0 K+) = (1.0 +/- 0.4 +/- 0.1) x 10(-6) and [symbol: see text](B0 --> K0 K0) = (0.8 +/- 0.3 +/- 0.1) x 10(-6). These decay modes are examples of hadronic bd transitions. No signal is observed in the decay B0 --> K+ K-, and we set an upper limit of 3.7 x 10(-7) at 90% confidence level.
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96
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Measurements of the branching fraction and polarization in B+ --> rho+ K*0 decays. PHYSICAL REVIEW LETTERS 2005; 95:141801. [PMID: 16241643 DOI: 10.1103/physrevlett.95.141801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2005] [Indexed: 05/05/2023]
Abstract
We present the results of a study of the charmless vector-vector decay B+ --> rho+ K*0, based on 253 fb(-1) of data collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. We obtain the branching fraction B(B+ --> rho+ K*0) = [8.9 +/- 1.7(stat) +/- 1.2(syst)] x 10(-6). We also perform a helicity analysis of the rho and K* vector mesons, and obtain the longitudinal polarization fraction f(L)(B+ --> rho+ K*0) = 0.43 +/- 0.11(stat)(-0.02)(+0.05) (syst).
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97
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Improved evidence for direct CP violation in B0-->pi+pi- decays and model-independent constraints on phi2. PHYSICAL REVIEW LETTERS 2005; 95:101801. [PMID: 16196917 DOI: 10.1103/physrevlett.95.101801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2005] [Indexed: 05/04/2023]
Abstract
We present a new measurement of the time-dependent CP-violating parameters in B(0)--> pi(+)pi(-) decays with 275 x 10(6) BB pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider operating at the Gamma(4S) resonance. We find 666 +/- 43 B(0) --> pi(+)pi(-) events and measure the CP-violating parameters: S(pipi) = -0.67 +/- 0.16(stat) +/- 0.06(syst) and A(pipi) = +0.56 +/- 0.12(stat) +/- 0.06(syst). We find evidence for large direct CP violation with a significance greater than 4 standard deviations for any S(pipi) value. Using isospin relations, we obtain 95.4% confidence intervals for the Cabibbo-Kobayashi-Maskawa quark-mixing matrix angle phi(2) of 0 degree < phiv(2) < 19 degrees and 71 degrees < phi(2) < 180 degrees.
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98
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Studies of CP violation in B-->J/PsiK* decays. PHYSICAL REVIEW LETTERS 2005; 95:091601. [PMID: 16197207 DOI: 10.1103/physrevlett.95.091601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2005] [Revised: 07/13/2005] [Indexed: 05/04/2023]
Abstract
CP violation in B-->J/PsiK* decays is studied using an angular analysis in a data sample of 253 fb(-1) recorded with the Belle detector at the KEKB e(+)e(-) collider. The flavor separated measurements of the decay amplitudes indicate no evidence for direct CP violation. T-odd CP violation is studied using the asymmetries in triple product correlations, and the results are consistent with the standard model null predictions. The time-dependent angular analysis gives the following values of CP-violating parameters: sin(2phi(1) = 0.24 +/- 0.31 +/- 0.05 and cos(2phi(1)=0.56 +/- 0.79 +/- 0.11.
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99
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Measurement of time-dependent CP-violating asymmetries in B0 --> K(s)0K(s)0K(s)0 decay. PHYSICAL REVIEW LETTERS 2005; 95:061801. [PMID: 16090938 DOI: 10.1103/physrevlett.95.061801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2005] [Indexed: 05/03/2023]
Abstract
We present a measurement of CP-violation parameters in the B0 --> K(s)0K(s)0K(s)0 decay based on a sample of 275 x 10(6) BB pairs collected at the upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e- collider. One neutral B meson is fully reconstructed in the decay B0 --> K(s)0K(s)0K(s)0, and the flavor of the accompanying B meson is identified from its decay products. CP-violation parameters are obtained from the asymmetry in the distributions of the proper-time interval between the two B decays: S = +1.26 +/- 0.68(stat) +/- 0.20(syst) and [symbol: see text] = +0.54 +/- 0.34(stat) +/- 0.09(syst).
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