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Erratum: Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande [Phys. Rev. Lett. 130, 031802 (2023)]. PHYSICAL REVIEW LETTERS 2023; 131:159903. [PMID: 37897794 DOI: 10.1103/physrevlett.131.159903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Indexed: 10/30/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.130.031802.
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Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC. PHYSICAL REVIEW LETTERS 2023; 130:061002. [PMID: 36827578 DOI: 10.1103/physrevlett.130.061002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 11/02/2022] [Accepted: 12/15/2022] [Indexed: 06/18/2023]
Abstract
Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28} cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25} cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.
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Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande. PHYSICAL REVIEW LETTERS 2023; 130:031802. [PMID: 36763398 DOI: 10.1103/physrevlett.130.031802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/30/2022] [Indexed: 06/18/2023]
Abstract
We report a search for cosmic-ray boosted dark matter with protons using the 0.37 megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1 MeV/c^{2} to 300 MeV/c^{2}.
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Neutron-antineutron oscillation search using a 0.37 megaton-years exposure of Super-Kamiokande. Int J Clin Exp Med 2021. [DOI: 10.1103/physrevd.103.012008] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C. PHYSICAL REVIEW LETTERS 2020; 125:021301. [PMID: 32701326 DOI: 10.1103/physrevlett.125.021301] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/20/2020] [Accepted: 06/04/2020] [Indexed: 06/11/2023]
Abstract
On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.
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Measurement of the tau neutrino cross section in atmospheric neutrino oscillations with Super-Kamiokande. Int J Clin Exp Med 2018. [DOI: 10.1103/physrevd.98.052006] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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8
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Search for Boosted Dark Matter Interacting with Electrons in Super-Kamiokande. PHYSICAL REVIEW LETTERS 2018; 120:221301. [PMID: 29906152 DOI: 10.1103/physrevlett.120.221301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 03/23/2018] [Indexed: 06/08/2023]
Abstract
A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.
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Abstract
Senescence marker protein-30 (SMP30) decreases androgen-independently with aging and is a lactone-hydrolyzing enzyme gluconolactonase (GNL) that is involved in vitamin C biosynthesis. In the present study, bone properties of SMP30/GNL knockout (KO) mice with deficiency in vitamin C synthesis were investigated to reveal the effects of SMP30/GNL and exogenous vitamin C supplementation on bone formation. Mineral content (BMC) and mineral density (BMD) of the mandible and femur of SMP30/GNL KO and wild-type mice at 2 and 3 months of age with or without vitamin C supplementation were measured by dual-energy X-ray absorptiometry. Body and bone weight of both age groups decreased and became significantly lower than those of wild-type mice. The bones of SMP30/GNL KO mice were rough and porous, with BMC and BMD significantly below wild-type. Oral supplementation with vitamin C eliminated differences in body weight, bone weight, BMC, and BMD between SMP30/GNL KO and wild-type mice at each age. These results indicate that bone degeneration in SMP30/GNL KO mice was caused by lack of vitamin C, and that this mouse strain is an appropriate model for bone metabolism in humans, which have no ability to synthesize vitamin C.
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Vitrification of mouse zygotes; effect of rapid warming. Cryobiology 2016. [DOI: 10.1016/j.cryobiol.2016.09.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Oxidative Stress-induced DNA Damage in the Synovial Cells of the Temporomandibular Joint in the Rat. J Dent Res 2016; 83:619-24. [PMID: 15271970 DOI: 10.1177/154405910408300807] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Synovial hyperplasia is a feature of degenerative temporomandibular joint (TMJ) disease. However, the mechanism by which hyperplasia progresses in the TMJ is unknown. Based on the hypothesis that the oxidative stress generated by mechanical loading causes degenerative changes in the TMJ synovium, we investigated the generation of the highly reactive species, peroxynitrite, and the occurrence of DNA damage in the synovium. After condylar hypermobility of rat TMJs, a marker of peroxynitrite, nitrotyrosine, was localized to the nuclei and cytoplasm of the synovial lining cells and fibroblasts in synovitis-induced TMJ. DNA single-strand breaks were found in the nuclei of the synovial cells only after enzyme treatment, whereas DNA double-strand breaks were not detected. These findings indicate that condylar hypermovement induces the proliferation of synovial cells, and suggest that oxidative stress leads to the progression of synovial hyperplasia via DNA damage of the synovial cells in TMJs after mechanical loading.
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Measurements of the atmospheric neutrino flux by Super-Kamiokande: Energy spectra, geomagnetic effects, and solar modulation. Int J Clin Exp Med 2016. [DOI: 10.1103/physrevd.94.052001] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Search for Nucleon and Dinucleon Decays with an Invisible Particle and a Charged Lepton in the Final State at the Super-Kamiokande Experiment. PHYSICAL REVIEW LETTERS 2015; 115:121803. [PMID: 26430987 DOI: 10.1103/physrevlett.115.121803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Indexed: 06/05/2023]
Abstract
Search results for nucleon decays p→e^{+}X, p→μ^{+}X, n→νγ (where X is an invisible, massless particle) as well as dinucleon decays np→e^{+}ν, np→μ^{+}ν, and np→τ^{+}ν in the Super-Kamiokande experiment are presented. Using single-ring data from an exposure of 273.4 kton·yr, a search for these decays yields a result consistent with no signal. Accordingly, lower limits on the partial lifetimes of τ_{p→e^{+}X}>7.9×10^{32} yr, τ_{p→μ^{+}X}>4.1×10^{32} yr, τ_{n→νγ}>5.5×10^{32} yr, τ_{np→e^{+}ν}>2.6×10^{32} yr, τ_{np→μ^{+}ν}>2.2×10^{32} yr, and τ_{np→τ^{+}ν}>2.9×10^{31} yr at a 90% confidence level are obtained. Some of these searches are novel.
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Search for neutrinos from annihilation of captured low-mass dark matter particles in the sun by super-kamiokande. PHYSICAL REVIEW LETTERS 2015; 114:141301. [PMID: 25910107 DOI: 10.1103/physrevlett.114.141301] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Indexed: 06/04/2023]
Abstract
Super-Kamiokande (SK) can search for weakly interacting massive particles (WIMPs) by detecting neutrinos produced from WIMP annihilations occurring inside the Sun. In this analysis, we include neutrino events with interaction vertices in the detector in addition to upward-going muons produced in the surrounding rock. Compared to the previous result, which used the upward-going muons only, the signal acceptances for light (few-GeV/c^{2}-200-GeV/c^{2}) WIMPs are significantly increased. We fit 3903 days of SK data to search for the contribution of neutrinos from WIMP annihilation in the Sun. We found no significant excess over expected atmospheric-neutrino background and the result is interpreted in terms of upper limits on WIMP-nucleon elastic scattering cross sections under different assumptions about the annihilation channel. We set the current best limits on the spin-dependent WIMP-proton cross section for WIMP masses below 200 GeV/c^{2} (at 10 GeV/c^{2}, 1.49×10^{-39} cm^{2} for χχ→bb[over ¯] and 1.31×10^{-40} cm^{2} for χχ→τ^{+}τ^{-} annihilation channels), also ruling out some fraction of WIMP candidates with spin-independent coupling in the few-GeV/c^{2} mass range.
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Authors' reply. BJOG 2015; 122:448-9. [PMID: 25623585 DOI: 10.1111/1471-0528.13259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2014] [Indexed: 11/29/2022]
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Search for nucleon decay via n→ν[over ¯]π0 and p→ν[over ¯]π+ in Super-Kamiokande. PHYSICAL REVIEW LETTERS 2014; 113:121802. [PMID: 25279622 DOI: 10.1103/physrevlett.113.121802] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Indexed: 06/03/2023]
Abstract
We present the results of searches for nucleon decay via n→ν[over ¯]π0 and p→ν[over ¯]π+ using data from a combined 172.8 kt·yr exposure of Super-Kamiokande-I,-II, and-III. We set lower limits on the partial lifetime for each of these modes: τn→ν[over ¯]π0>1.1×10(33) years and τp→ν[over ¯]π+>3.9×10(32) years at a 90% confidence level.
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Search for bosonic superweakly interacting massive dark matter particles with the XMASS-I detector. PHYSICAL REVIEW LETTERS 2014; 113:121301. [PMID: 25279618 DOI: 10.1103/physrevlett.113.121301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Indexed: 06/03/2023]
Abstract
Bosonic superweakly interacting massive particles (super-WIMPs) are a candidate for warm dark matter. With the absorption of such a boson by a xenon atom, these dark matter candidates would deposit an energy equivalent to their rest mass in the detector. This is the first direct detection experiment exploring the vector super-WIMPs in the mass range between 40 and 120 keV. With the use of 165.9 day of data, no significant excess above background was observed in the fiducial mass of 41 kg. The present limit for the vector super-WIMPs excludes the possibility that such particles constitute all of dark matter. The absence of a signal also provides the most stringent direct constraint on the coupling constant of pseudoscalar super-WIMPs to electrons. The unprecedented sensitivity was achieved exploiting the low background at a level 10(-4) kg-1 keVee-1 day-1 in the detector.
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Search for trilepton nucleon decay via p→e+νν and p→μ+νν in the Super-Kamiokande experiment. PHYSICAL REVIEW LETTERS 2014; 113:101801. [PMID: 25238348 DOI: 10.1103/physrevlett.113.101801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Indexed: 06/03/2023]
Abstract
The trilepton nucleon decay modes p→e+νν and p→μ+νν violate |Δ(B-L)| by two units. Using data from a 273.4 kt yr exposure of Super-Kamiokande a search for these decays yields a fit consistent with no signal. Accordingly, lower limits on the partial lifetimes of τp→e+νν>1.7×10(32) years and τp→μ+νν>2.2×10(32) years at a 90% confidence level are obtained. These limits can constrain Grand Unified Theories which allow for such processes.
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Authors' reply: transverse uterine fundal incision in placenta praevia with possible placenta accreta. BJOG 2014; 121:771-2. [PMID: 24738902 DOI: 10.1111/1471-0528.12556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2013] [Indexed: 11/30/2022]
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Authors' reply: placenta praevia accreta. BJOG 2014; 121:773-5. [PMID: 24738904 DOI: 10.1111/1471-0528.12555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/03/2013] [Indexed: 11/29/2022]
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Authors' reply: transverse uterine fundal incision for placenta praevia with accreta. BJOG 2014; 121:769-70. [PMID: 24738900 DOI: 10.1111/1471-0528.12550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2013] [Indexed: 12/01/2022]
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Search for dinucleon decay into kaons in Super-Kamiokande. PHYSICAL REVIEW LETTERS 2014; 112:131803. [PMID: 24745406 DOI: 10.1103/physrevlett.112.131803] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Indexed: 06/03/2023]
Abstract
A search for the dinucleon decay pp → K+ K+ has been performed using 91.6 kton·yr data from Super-Kamiokande-I. This decay provides a sensitive probe of the R-parity-violating parameter λ112''. A boosted decision tree analysis found no signal candidates in the data. The expected background was 0.28±0.19 atmospheric neutrino induced events and the estimated signal detection efficiency was 12.6%±3.2%. A lower limit of 1.7×10(32) years has been placed on the partial lifetime of the decay O16 → C14K+ K+ at 90% C.L. A corresponding upper limit of 7.8×10(-9) has been placed on the parameter λ112''.
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First indication of terrestrial matter effects on solar neutrino oscillation. PHYSICAL REVIEW LETTERS 2014; 112:091805. [PMID: 24655245 DOI: 10.1103/physrevlett.112.091805] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Indexed: 06/03/2023]
Abstract
We report an indication that the elastic scattering rate of solar B8 neutrinos with electrons in the Super-Kamiokande detector is larger when the neutrinos pass through Earth during nighttime. We determine the day-night asymmetry, defined as the difference of the average day rate and average night rate divided by the average of those two rates, to be [-3.2 ± 1.1(stat) ± 0.5(syst)]%, which deviates from zero by 2.7 σ. Since the elastic scattering process is mostly sensitive to electron-flavored solar neutrinos, a nonzero day-night asymmetry implies that the flavor oscillations of solar neutrinos are affected by the presence of matter within the neutrinos' flight path. Super-Kamiokande's day-night asymmetry is consistent with neutrino oscillations for 4 × 10(-5) eV(2) ≤ Δm 2(21) ≤ 7 × 10(-5) eV(2) and large mixing values of θ12, at the 68% C.L.
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Evidence for the appearance of atmospheric tau neutrinos in super-Kamiokande. PHYSICAL REVIEW LETTERS 2013; 110:181802. [PMID: 23683190 DOI: 10.1103/physrevlett.110.181802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Indexed: 06/02/2023]
Abstract
Super-Kamiokande atmospheric neutrino data were fit with an unbinned maximum likelihood method to search for the appearance of tau leptons resulting from the interactions of oscillation-generated tau neutrinos in the detector. Relative to the expectation of unity, the tau normalization is found to be 1.42 ± 0.35(stat)(-0.12)(+0.14)(syst) excluding the no-tau-appearance hypothesis, for which the normalization would be zero, at the 3.8σ level. We estimate that 180.1 ± 44.3(stat)(-15.2)(+17.8) (syst) tau leptons were produced in the 22.5 kton fiducial volume of the detector by tau neutrinos during the 2806 day running period. In future analyses, this large sample of selected tau events will allow the study of charged current tau neutrino interaction physics with oscillation produced tau neutrinos.
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Transverse uterine fundal incision for placenta praevia with accreta, involving the entire anterior uterine wall: a case series. BJOG 2013; 120:1144-9. [DOI: 10.1111/1471-0528.12252] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/08/2013] [Indexed: 10/26/2022]
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Delaying embryo development by storing at 4°C for synchronization to recipients in microinjection technique in rabbits. Lab Anim 2012; 47:53-7. [PMID: 23258842 DOI: 10.1258/la.2012.012097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Short-term storage of embryos at low temperature induces developmental arrest of the embryo and would appear to be a valuable aid in embryo-transfer techniques to avoid wasting embryos. Embryo storage at 4°C was examined to allow synchronization with embryo-transfer recipients using the microinjection technique. Superovulation was induced in female Japanese White donor rabbits four days before mating with males. At the same time, control recipients were injected with human chorionic gonadotropin (hCG) to allow synchronization (R1); the hCG injections were delayed by 24 h in the experimental group (R2). DNA constructs for expressing human C-reactive protein or apolipoprotein AII were microinjected into the male pronuclei of the ova. The microinjected embryos were immediately transferred to recipients (R1) or stored at 4°C in phosphate-buffered saline containing 10% fetal bovine serum. After 17-20 h, the stored embryos were incubated at 37°C for one hour, and the morphologically normal embryos were transferred to recipients (R2). In the R1 rabbits, 855 embryos were transferred to 29 recipients, and 72.4% of the recipients became pregnant. Seven of the 84 offspring were transgenic. In the R2 rabbits, 478 embryos were transferred to 16 recipients, and 62.5% of the recipients became pregnant. Two of the 39 offspring were transgenic. There were no differences in pregnancy rate, litter size and transgenic integration rate between R1 and R2. These results suggest that the short-term 4°C storage of microinjected embryos can be a valuable method for synchronization with recipients, and reducing wastage of embryos and the sacrifice of rabbits.
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Search for differences in oscillation parameters for atmospheric neutrinos and antineutrinos at Super-Kamiokande. PHYSICAL REVIEW LETTERS 2011; 107:241801. [PMID: 22242990 DOI: 10.1103/physrevlett.107.241801] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Indexed: 05/31/2023]
Abstract
We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3) eV2, 1.0) and is consistent with the overall Super-K measurement.
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The effects of cell adhesion on the growth and protein productivity of animal cells. Cytotechnology 2011; 33:147-55. [PMID: 19002822 DOI: 10.1023/a:1008189802014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
We investigated the effect of cell adhesion on cellgrowth and productivity of recombinant protein inChinese hamster ovary (CHO) cells. Cells cultured innormal tissue culture dishes attached to the dishsurfaces and grew as a monolayer, while cells culturedin non-treated dishes proliferated in suspension assingle cells without adhering to the dish surfaces. On an agarose-coated dish surface, cell aggregatesformed without attaching to the dish. Growth rates inboth suspension cultures were slightly lower thanthose in monolayer culture. Cell cycle analysisindicated that the duration of the G(1) phase insuspension cultures was longer than that in monolayerculture, suggesting that attachment to the substratummainly affected the transition from the G(1) to theS phase. Consistent with this, CDK inhibitor p27,that inhibits the G(1)S transition, was induced inthe cells cultured in suspension.To assess the productivity of recombinant proteins,CHO cells were transfected with a plasmid containingmurine interferon gamma (mIFN-gamma) under thecontrol of the cytomegalovirus promoter. Insuspension culture, mIFN-gamma productivity wasslightly lower than that in the monolayer culture. When protein kinase C was activated by phorbol ester,mIFN-gamma production was enhanced in both themonolayer and suspension cultures. However, theproductivity in the suspension culture was lower thanthat in the adherent culture even in the presence ofhigh concentrations of phorbol ester. These resultssuggested that cell adhesion to the substratum affectsvarious features of CHO cells.
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Structural changes of fovea during remission of Behçet's disease as imaged by spectral domain optical coherence tomography. Eye (Lond) 2009; 24:969-75. [DOI: 10.1038/eye.2009.231] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Search for proton decay via p-->e+pi0 and p-->micro+pi0 in a large water Cherenkov detector. PHYSICAL REVIEW LETTERS 2009; 102:141801. [PMID: 19392425 DOI: 10.1103/physrevlett.102.141801] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Indexed: 05/27/2023]
Abstract
We have searched for proton decays via p-->e;{+}pi;{0} and p-->micro;{+}pi;{0} using data from a 91.7 kt.yr exposure of Super-Kamiokande-I and a 49.2 kt.yr exposure of Super-Kamiokande-II. No candidate events were observed with expected backgrounds induced by atmospheric neutrinos of 0.3 events for each decay mode. From these results, we set lower limits on the partial lifetime of 8.2 x 10;{33} and 6.6 x 10;{33} years at 90% confidence level for p-->e;{+}pi;{0} and p-->micro;{+}pi;{0} modes, respectively.
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Randomised controlled trial of posterior sub-Tenon triamcinolone as adjunct to panretinal photocoagulation for treatment of diabetic retinopathy. Br J Ophthalmol 2009; 93:765-70. [DOI: 10.1136/bjo.2008.152041] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Amplification of competitive telomere sequence in living animal cells induces chromatin instability. Cytotechnology 2008; 31:195-203. [PMID: 19003141 DOI: 10.1023/a:1008088609398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We have reported the establishment of new episomal-type expression vector the copy number of which can be readily regulated by a temperature shift. In this study, we attempt to apply this vector for the functional analysis of the noncoding regions of DNA. A plasmid containing a 0.45 kb-telomere repeat sequence was constructed and transfected into simian CV-1 cells, leading to successful establishment of cell lines in which episomal telomere sequence could be amplified by temperature shift. When the episomal telomere sequence was amplified, the cells stopped proliferating at the G(2)/M phase of the cell cycle and exhibited a large size with flattened morphology and several small nucleus-like particles. These cells expressed Cdk inhibitor p21 and beta-galactosidase, which are expressed in some senescent cells. Microscopic analysis revealed frequent end-to-end attachments of chromosomes, which resulted in a variety of aberrant chromosome configurations. None of these characteristics was observed in nontransfected and control plasmid-transfected CV-1 cells at any cultivation temperature. These results indicate the usefulness of our vector system in analyzing telomeric DNA.
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Measurement of atmospheric neutrino flux consistent with tau neutrino appearance. PHYSICAL REVIEW LETTERS 2006; 97:171801. [PMID: 17155460 DOI: 10.1103/physrevlett.97.171801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2006] [Indexed: 05/12/2023]
Abstract
A search for the appearance of tau neutrinos from nu(mu) <--> nu(tau) oscillations in the atmospheric neutrinos has been performed using 1489.2 days of atmospheric neutrino data from the Super-Kamiokande-I experiment. A best fit tau neutrino appearance signal of 138+/-48(stat)-32(+15)(syst) events is obtained with an expectation of 78+/-26(syst). The hypothesis of no tau neutrino appearance is disfavored by 2.4 sigma.
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Is gestational week at birth a predictor of schizophrenia? Br J Psychiatry 2005; 187:589; author reply 589. [PMID: 16353413 DOI: 10.1192/bjp.187.6.589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Integrase-mediated nonviral gene transfection with enhanced integration efficiency. J Biosci Bioeng 2005; 88:461-7. [PMID: 16232645 DOI: 10.1016/s1389-1723(00)87659-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/1999] [Accepted: 08/16/1999] [Indexed: 11/26/2022]
Abstract
Retroviruses efficiently integrate their genome into the host chromosome. Two elements of the retrovirus genome are needed for the integration: long terminal repeats (LTRs) and integrase protein. We attempted to incorporate the retrovirus integration machinery in lipid vesicle-mediated gene transfection with the aim of achieving efficient stable transfection in a nonviral gene transfection system. A DNA fragment, in which a neomycin-resistant gene was flanked between partial LTR sequences derived from the Rous sarcoma virus (RSV), was constructed. This DNA fragment was transfected together with purified recombinant RSV integrase or integrase expression vectors by means of lipid vesicle-mediated gene transfection. The integrase-mediated transfection enhanced the stable transfection efficiency. The length and the end structure of the LTR sequences were important in achieving high efficiency. Under optimal conditions, the stable transfection efficiency showed a 16-fold improvement over that without integrase.
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Abstract
AIMS Diabetic patients may have abnormal inflammatory reactions to foreign or endogenous stimuli. This study was designed to evaluate inflammatory reactions in the diabetic eye through retinal leucocyte dynamics in the inflamed eyes of diabetic rats. METHODS Three weeks after diabetes induction in Long-Evans rats, endotoxin induced uveitis was produced by footpad injection of lipopolysaccharide (LPS). After LPS injection, leucocyte behaviour was evaluated in vivo by acridine orange digital fluorography. RESULTS The number of rolling leucocytes increased in a biphasic manner at 12 hours and 48 hours. The number of leucocytes accumulating in the retina reached a peak at 72 hours. The maximal numbers of rolling and accumulating leucocytes in the diabetic retina decreased by 56.3% (p<0.01) and 46.7% (p<0.0001), respectively, compared with the non-diabetic retina. The levels of mRNA expression of adhesion molecules in the retina, which were upregulated after LPS injection, were also lower in diabetic rats than in non-diabetic rats. CONCLUSION This study is the first to show that endotoxin induced inflammation is disturbed in the diabetic eye, based on evidence that the leucocyte-endothelial cell interactions stimulated by LPS were suppressed in the diabetic retina. These findings support the theory that ocular inflammatory reactions are impaired in diabetic patients.
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Crystal structure of MCoA-ACPT from Thermus thermophilusHB8. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305079729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Preparation and pharmaceutical evaluation for clinical application of high specific activity S-(-)[11C]CGP-12177, a radioligand for beta-adrenoreceptors. Nucl Med Commun 2005; 25:845-9. [PMID: 15266181 DOI: 10.1097/01.mnm.0000134320.39903.75] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Although S-(-)[C]CGP-12177 is a useful positron emission tomography (PET) ligand for beta-adrenoreceptors, the difficulty in radiolabelling the compound has prevented its extensive clinical application. Recently, we have developed a simple synthesis method for S-(-)[C]CGP-12177. In the present study, we attempted to prepare S-(-)[C]CGP-12177 with a high specific activity for intravenous injection which is feasible for the clinical evaluation of beta-adrenoreceptors. METHODS The [C]methane produced during irradiation of a N2--H2 (95/5) mixture with an 18 MeV proton beam (20 microA, 30 min) was chlorinated using Cl2 to yield [C]carbon tetrachloride. S-(-)[C]CGP-12177 was synthesized by reacting the diamino precursor with [C]phosgene produced by oxidizing [C]carbon tetrachloride on a Fe--Fe2O3 column. The product was purified by using reversed phase, high-performance liquid chromatography (RP-HPLC) and the radioactive fraction containing S-(-)[C]CGP-12177 was collected and evaporated to dryness. S-(-)[C]CGP-12177 dissolved in physiological saline was sterilized through a 0.22 microm membrane filter. The radiochemical purity and the mass of the compound were determined with RP-HPLC. The residual organic solvents were determined with GC. Tests for sterility and the presence of bacterial endotoxins were also performed. RESULTS S-(-)[C]CGP-12177 for intravenous injection was prepared in 25 min after the end of bombardment with a yield of 1.5+/-0.2 GBq. Specific activity was found to be 385.4+/-133.0 GBq/ micromol at the end of synthesis (EOS) (n=3). Radiochemical purity was found to be more than 99%. Toluene was not detected in the solution. The ethanol concentration was determined to be 60.3+/-52.5 ppm. Tests for sterility and bacterial endotoxins showed negative results. CONCLUSION We successfully prepared S-(-)[C]CGP-12177 formulated for intravenous injection with high purity and high specific activity, which is feasible for the clinical evaluation of beta-adrenoreceptors.
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Abstract
In cases with placenta accreta occurring on the previous cesarean scar, a longitudinal incision is generally appropriate. However, the placenta may prevent both a longitudinal and lower transverse incision. We report a case of placenta increta on the previous cesarean scar, and discuss the role of transverse fundal uterine incision.
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Evidence for an oscillatory signature in atmospheric neutrino oscillations. PHYSICAL REVIEW LETTERS 2004; 93:101801. [PMID: 15447395 DOI: 10.1103/physrevlett.93.101801] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2004] [Indexed: 05/14/2023]
Abstract
Muon neutrino disappearance probability as a function of neutrino flight length L over neutrino energy E was studied. A dip in the L/E distribution was observed in the data, as predicted from the sinusoidal flavor transition probability of neutrino oscillation. The observed L/E distribution constrained nu(micro)<-->nu(tau) neutrino oscillation parameters; 1.9x10(-3)<Deltam(2)<3.0x10(-3) eV(2) and sin((2)2theta>0.90 at 90% confidence level.
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Limits on the neutrino magnetic moment using 1496 days of Super-Kamiokande-I solar neutrino data. PHYSICAL REVIEW LETTERS 2004; 93:021802. [PMID: 15323899 DOI: 10.1103/physrevlett.93.021802] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2004] [Indexed: 05/24/2023]
Abstract
A search for a nonzero neutrino magnetic moment has been conducted using 1496 live days of solar neutrino data from Super-Kamiokande-I. Specifically, we searched for distortions to the energy spectrum of recoil electrons arising from magnetic scattering due to a nonzero neutrino magnetic moment. In the absence of a clear signal, we found micro(nu)</=(3.6x10(-10))micro(B) at 90% C.L. by fitting to the Super-Kamiokande day-night spectra. The fitting took into account the effect of neutrino oscillation on the shapes of energy spectra. With additional information from other solar neutrino and KamLAND experiments constraining the oscillation region, a limit of micro(nu)</=(1.1x10(-10))micro(B) at 90% C.L. was obtained.
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Ileocolic Intussusception in an Adult Caused by an Intramuscular Lipoma of the Ileum: Report of a Case. Visc Med 2004. [DOI: 10.1159/000079231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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