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This corrects the article DOI: 10.1103/PhysRevLett.130.031802.
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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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The aim of this phase II, multicentre, randomized controlled trial was to evaluate the effectiveness of a comprehensive oral management protocol for the prevention of severe oral mucositis in patients with oral cancer receiving radiotherapy alone or chemoradiotherapy. In total, 124 patients with oral cancer were enrolled from five institutions. Of these, 37 patients undergoing radiotherapy were randomly divided into an intervention group (n=18) and a control group (n=19). The remaining 87 patients, who were undergoing chemoradiotherapy, were also randomized into an intervention group (n=42) and a control group (n=45). During radiotherapy, patients in the control group received only oral care, while those in the intervention group additionally received spacers to cover the entire dentition, pilocarpine hydrochloride, and topical dexamethasone ointment for oral mucositis. The primary endpoint was the incidence of severe oral mucositis. The intervention was significantly associated with a decreased incidence of severe oral mucositis in patients receiving radiotherapy alone (P=0.046), but not in those receiving chemoradiotherapy (P=0.815). These findings suggest that an oral management protocol can prevent severe oral mucositis in patients with oral cancer undergoing radiotherapy without concurrent chemotherapy.
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Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Estomatitis , Administración Oral , Quimioradioterapia , HumanosRESUMEN
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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Search results for nucleon decays pâe^{+}X, pâµ^{+}X, nâνγ (where X is an invisible, massless particle) as well as dinucleon decays npâe^{+}ν, npâµ^{+}ν, and npâτ^{+}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_{pâe^{+}X}>7.9×10^{32} yr, τ_{pâµ^{+}X}>4.1×10^{32} yr, τ_{nâνγ}>5.5×10^{32} yr, τ_{npâe^{+}ν}>2.6×10^{32} yr, τ_{npâµ^{+}ν}>2.2×10^{32} yr, and τ_{npâτ^{+}ν}>2.9×10^{31} yr at a 90% confidence level are obtained. Some of these searches are novel.
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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 χχâbb[over ¯] and 1.31×10^{-40} cm^{2} for χχâτ^{+}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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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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We present the results of searches for nucleon decay via nâν[over ¯]π0 and pâν[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: τnâν[over ¯]π0>1.1×10(33) years and τpâν[over ¯]π+>3.9×10(32) years at a 90% confidence level.
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The trilepton nucleon decay modes pâe+νν and pâµ+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 τpâe+νν>1.7×10(32) years and τpâµ+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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A search for the dinucleon decay pp â 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 â 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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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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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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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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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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BACKGROUND AND OBJECTIVE: The types of collagens available today as biomaterials are purified from animal tissues. A major growing concern, however, is their safety, since there are risks of viral and prion contamination and of unknown and potentially zoonotic infectious diseases. The present study aimed to assess, using immunohistochemistry, the effects of recombinant human growth/differentiation factor-5 (rhGDF-5) combined with recombinant human collagen I (rhCI) on bone formation in murine calvariae. MATERIAL AND METHODS: Composite rhGDF-5-rhCI or rhCI alone was injected subcutaneously into murine calvariae. After 3, 7 or 14 days, tissues were examined radiologically, histologically and immunohistochemically. The production of vascular endothelial growth factor (VEGF) by primary osteoblasts, periosteal cells and connective tissue fibroblasts isolated enzymatically from neonatal murine calvariae was also assessed. RESULTS: A protrusion was observed on the calvariae at the site injected with rhGDF-5/rhCI composite. Its mineral density was shown to be different from that of the existing bone by two-dimensional microcomputed tomography. Type II collagen-positive staining was restricted to newly formed tissues. Thus, the newly formed tissues seemed to be bone- and cartilage-like tissues. A number of vessels with positively stained cells for Von Willebrand factor were detected in the newly formed tissues. The rhGDF-5 enhanced VEGF production in cultured connective tissue fibroblasts. Sry-related HMG box 9 (Sox9)-positive cells were detected in the hypertrophic periosteum, and penetrated into the newly formed tissues. CONCLUSIONS: These results suggest that rhCI seems to allow the release of rhGDF-5 and that rhGDF-5-rhCI composite induces endochondral ossification via Sox9 expression and angiogenesis in murine calvariae.
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Colágeno Tipo I/farmacología , Factor 5 de Diferenciación de Crecimiento/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Factor de Transcripción SOX9/biosíntesis , Animales , Animales Recién Nacidos , Células Cultivadas , Colágeno Tipo I/administración & dosificación , Fibroblastos/metabolismo , Factor 5 de Diferenciación de Crecimiento/administración & dosificación , Factor 5 de Diferenciación de Crecimiento/fisiología , Humanos , Inmunohistoquímica , Inyecciones Subcutáneas , Ratones , Neovascularización Fisiológica/fisiología , Osteoblastos/metabolismo , Osteogénesis/fisiología , Periostio/citología , Periostio/metabolismo , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Factor de Transcripción SOX9/fisiología , Cráneo/cirugía , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Factor de von Willebrand/biosíntesisRESUMEN
Talar head fractures are rare injuries. We present a 26-year-old man with malunion of the talar head. The displaced fracture was initially neglected. The patient was treated with osteotomy and bone grafting to improve the congruity and movement of the talonavicular joint. Three months after surgery, he returned to his pre-injury activity level with no disability.
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Fracturas Óseas/cirugía , Fracturas Mal Unidas/cirugía , Osteotomía , Astrágalo/lesiones , Adulto , Trasplante Óseo , Humanos , Masculino , Astrágalo/cirugíaRESUMEN
Pigmented villonodular synovitis of the elbow is rare and even rarer in children. We report a case of pigmented villonodular synovitis of the elbow in a 6-year-old girl who underwent total synovectomy after the diagnosis was confirmed by biopsy. The osteochondral defect at the olecranon was filled with calcium phosphate bone paste. Two years after surgery, neither recurrence nor joint degeneration was found.
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Articulación del Codo , Sinovitis Pigmentada Vellonodular/cirugía , Niño , Articulación del Codo/diagnóstico por imagen , Articulación del Codo/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Radiografía , Sinovectomía , Sinovitis Pigmentada Vellonodular/diagnóstico por imagenRESUMEN
We present a case of recurrent saddle embolism 6 days and 9 days following corrective osteotomy of the left femur in a 64-year-old man with a history of atrial fibrillation. Although saddle embolism is a relatively rare event, orthopaedic surgeons should be aware of this condition.
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Arteriopatías Oclusivas/etiología , Embolia/etiología , Osteotomía , Complicaciones Posoperatorias , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/cirugía , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , Ecocardiografía Transesofágica , Embolectomía , Embolia/diagnóstico por imagen , Embolia/cirugía , Fracturas del Fémur/cirugía , Fibrinolíticos/uso terapéutico , Fracturas Mal Unidas/cirugía , Cardiopatías/diagnóstico por imagen , Cardiopatías/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Radiografía , Recurrencia , Trombosis/diagnóstico por imagen , Trombosis/epidemiología , Ticlopidina/uso terapéuticoRESUMEN
We present a case of tarsal tunnel syndrome caused by an amyloidoma arising from the talocalcaneal joint in a 64-year-old man with a long history of haemodialysis. He presented with numbness in the medial plantar area of the right foot without any antecedent trauma. The numbness was minimal at rest but gradually worsened, causing difficulty, when walking. Paraesthesia was present on the medial sole of the right foot. A positive Tinel-like sign was noted 2.5 cm below the medial malleolus. Magnetic resonance imaging demonstrated a round lesion, 1 cm in diameter, in the calcaneus, which was hypointense on T1-weighted images and hyperintense on T2-weighted images. In addition, a mass, 1 cm in diameter with a signal isointense to that of muscle was found adjacent to the talocalcaneal joint. The medial plantar nerve was decompressed after removing a solid, 1-cm diameter mass from the talocalcaneal joint. At 6 months post surgery, the numbness had completely resolved. No recurrence was observed at the 24-month follow-up.
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Amiloidosis/complicaciones , Artropatías/complicaciones , Diálisis Renal , Articulación Talocalcánea , Síndrome del Túnel Tarsiano/etiología , Humanos , Masculino , Persona de Mediana Edad , Síndrome del Túnel Tarsiano/cirugía , Factores de TiempoRESUMEN
Details of the mechanical properties of hinged external fixators are essential to use the fixator properly in the clinical setting. A hinged external fixator (Dynamic Joint Distractor 2) was attached to the lateral side of 7 cadaveric elbows. Cantilever lateral bending tests were performed at 3 flexion angles in varus and valgus directions. Varied states of joint contact and axial loading were studied. Stiffness of the construct was calculated with uniaxial loading. Stiffness decreased with increased elbow flexion. Gap creation made the system less stiff. Axial loading made the system stiffer, especially in valgus testing. Stiffness in varus was approximately 4 times that in valgus. Lateral fixator application with half pins is most effective for protecting against varus-producing forces. When using the external fixator for unstable elbows, attention should be paid to the status of the articular surfaces and the integrity of the ligaments, and this should also be noted for elbow position during rehabilitation.