RESUMO
Over 99% of human rabies cases in endemic areas are transmitted by dogs. Without the elimination of dog rabies, it is not easy to reduce human rabies infection. Controlling dog rabies, especially in ownerless or free-roaming dogs, is critical if we are to decrease the rate of human rabies infection. There are several components in a strategy to eliminate dog-mediated rabies in Asia. Each government must make sure that rabies is either a reportable disease or a notifiable disease and enforce the reporting requirements accordingly. They must also focus on organising and operating special rabies control committees that work with relevant agencies under the 'One Health' banner. They should also implement a national rabies control programme that includes mass dog vaccination, laboratory-based surveillance, stable budget allocation, a rapidreporting system, management of dog populations, international cooperation, prevention of animal introductions from other countries, and risk assessment to analyse the programme's weaknesses. As several developed countries have shown, an effective rabies control strategy leads to rabies-free status. In the Republic of Korea, human rabies has not occurred since 2004, and there have not been any confirmed cases of dog rabies or cases of rabies in wild animals, including raccoon dogs, since 2014. The successful implementation of the key strategies used to eliminate rabies in the Republic of Korea will enable other Asian countries to eliminate dog-mediated human rabies.
Plus de 99 % des cas humains de rage survenant dans les zones où cette maladie est endémique sont dus à des morsures de chiens. Il paraît difficile de réduire le nombre d'êtres humains infectés par le virus de la rage sans éliminer la rage canine. Le contrôle de la rage canine, en particulier dans les populations de chiens sans propriétaire ou errants est une condition essentielle si nous voulons faire baisser l'incidence de la rage humaine. La stratégie d'élimination de la rage transmise par les chiens en Asie comporte plusieurs composantes. Les gouvernements doivent s'assurer que la rage est une maladie à déclaration ou notification obligatoires et que les dispositions prévues en matière de déclaration sont bien appliquées. Ils doivent également axer leurs efforts sur la mise en place et le bon fonctionnement de commissions compétentes en matière de lutte contre la rage, qui opéreront en collaboration avec les agences pertinentes sous la bannière « Une seule santé ¼. En outre, chaque pays mettra en oeuvre un programme national de lutte contre la rage en intégrant toutes ses composantes : vaccination des chiens, surveillance sérologique, enveloppe budgétaire stable, système de notification accélérée, gestion des populations de chiens, coopération internationale, prévention de l'introduction d'animaux à partir d'autres pays et enfin évaluation des risques en vue d'analyser les faiblesses du programme. Ainsi que l'ont montré plusieurs pays développés, les stratégies efficaces de lutte contre la rage permettent d'atteindre le statut indemne de rage. En république de Corée, aucun cas de rage n'a été signalé chez l'homme depuis 2004 ; de même, aucun cas de rage n'a été confirmé chez le chien ni dans la faune sauvage, y compris chez le chien viverrin, depuis 2014. L'exemple des stratégies d'élimination de la rage appliquées avec succès en république de Corée permettra à d'autres pays asiatiques de venir à bout de la rage humaine transmise par le chien.
Los perros son los transmisores de más del 99% de los casos de rabia humana que se dan en las zonas de endemismo. De ahí la dificultad de reducir el número de personas infectadas si no se logra previamente eliminar la enfermedad en el perro, o dicho de otro modo: el control de la rabia canina, sobre todo en los perros vagabundos o sin dueño, es esencial para lograr menores índices de infección humana. Una estrategia encaminada a eliminar la rabia transmitida por perros en Asia ha de tener varios componentes. Todos los gobiernos deben hacer de la rabia una enfermedad de notificación obligatoria y hacer aplicar en consecuencia las reglas al respecto. También deben privilegiar la creación y el funcionamiento de comités especiales de lucha antirrábica que trabajen con los organismos competentes desde la lógica y los postulados de «Una sola salud¼. Además, deben instituir un programa nacional de lucha contra la rabia que, además de la vacunación masiva de perros, incluya planes de vigilancia en laboratorio, una partida presupuestaria estable, un sistema de notificación rápida, la gestión de las poblaciones caninas, la cooperación internacional, la prevención de la introducción de animales desde otros países y un proceso de determinación del riesgo para analizar los puntos débiles del programa. Como ha quedado patente en varios países desarrollados, una estrategia eficaz de lucha antirrábica acaba conduciendo a la condición de país libre de la enfermedad. En la República de Corea no se han producido casos de rabia humana desde 2004, y no ha habido ningún caso confirmado de rabia canina ni de rabia en animales silvestres, perros mapaches inclusive, desde 2014. La eficaz aplicación de las estrategias fundamentales empleadas en la República de Corea para eliminar la enfermedad hará posible que otros países asiáticos logren eliminar la rabia humana transmitida por perros.
Assuntos
Doenças do Cão/prevenção & controle , Saúde Única , Vacina Antirrábica/imunologia , Raiva/veterinária , Animais , Animais Selvagens , Ásia/epidemiologia , Erradicação de Doenças , Cães , Humanos , Cooperação Internacional , Vacinação em Massa , Raiva/prevenção & controle , Raiva/transmissãoRESUMO
We observe D(0)-D(0) mixing in the decay D(0) â K+π- using a data sample of integrated luminosity 976 fb(-1) collected with the Belle detector at the KEKB e+e- asymmetric-energy collider. We measure the mixing parameters x'(2) = (0.09 ± 0.22) × 10(-3) and y'=(4.6 ± 3.4) × 10(-3) and the ratio of doubly Cabibbo-suppressed to Cabibbo-favored decay rates R(D) = (3.53 ± 0.13) × 10(-3), where the uncertainties are statistical and systematic combined. Our measurement excludes the no-mixing hypothesis at the 5.1 standard deviation level.
RESUMO
We present the first model-independent measurement of the absolute branching fraction of the Λ(c)(+) â pK(-)π(+) decay using a data sample of 978 fb(-1) collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The number of Λ(c)(+) baryons is determined by reconstructing the recoiling D((*)-) pπ(+) system in events of the type e(+)e(-) â D((*)-) pπ(+)Λ(c)(+). The branching fraction is measured to be B(Λ(c)(+) â pK(-)π(+)) = (6.84 ± 0.24(-0.27)(+0.21))%, where the first and second uncertainties are statistical and systematic, respectively.
RESUMO
Equal amounts of matter and antimatter are predicted to have been produced in the Big Bang, but our observable Universe is clearly matter-dominated. One of the prerequisites for understanding this elimination of antimatter is the nonconservation of charge-parity (CP) symmetry. So far, two types of CP violation have been observed in the neutral K meson (K(0)) and B meson (B(0)) systems: CP violation involving the mixing between K(0) and its antiparticle (and likewise for B(0) and ), and direct CP violation in the decay of each meson. The observed effects for both types of CP violation are substantially larger for the B(0) meson system. However, they are still consistent with the standard model of particle physics, which has a unique source of CP violation that is known to be too small to account for the matter-dominated Universe. Here we report that the direct CP violation in charged B(+/-)-->K(+/-)pi(0) decay is different from that in the neutral B(0) counterpart. The direct CP-violating decay rate asymmetry, (that is, the difference between the number of observed B(-)-->K(-)pi(0) event versus B(+)-->K(+) pi(0) events, normalized to the sum of these events) is measured to be about +7%, with an uncertainty that is reduced by a factor of 1.7 from a previous measurement. However, the asymmetry for versus B(0)-->K(+)pi(-) is at the -10% level. Although it is susceptible to strong interaction effects that need further clarification, this large deviation in direct CP violation between charged and neutral B meson decays could be an indication of new sources of CP violation-which would help to explain the dominance of matter in the Universe.
RESUMO
Brugmansia suaveolens, also known as angel's trumpet, is a semi-woody shrub or a small tree. Because flowers of B. suaveolens are remarkably beautiful and sweetly fragrant, B. suaveolens is grown as ornamentals outdoors year-round in the tropics and subtropics, and as potted plants in temperate regions (1). In February 2013, virus-like symptoms including mosaic symptoms followed by distortion of leaves were observed in a potted B. suaveolens in a nursery in Chung-Nam Province, Korea. Symptomatic leaves were analyzed for the presence of several ornamental viruses including Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV), Tomato bush stunt virus (TBSV), and Tomato spotted wilt virus (TSWV) by immune-strip diagnostic kits that were developed by our laboratory. Positive controls and extract from healthy leaves of B. suaveolens as a negative control were included in each immune-strip assay. TSWV was detected serologically from the naturally infected B. suaveolens, but CMV, TBSV, and TMV were not detected from the B. suaveolens. The presence of TSWV (named TSWV-AT1) was confirmed by commercially available double-antibody sandwich (DAS)-ELISA kits (Agdia, Elkhart, IN). TSWV-AT1 was mechanically transmitted from the ELISA-positive B. suaveolens to Capsicum annuum and Nicotiana glutinosa, respectively. Inoculated C. annuum showed chlorotic rings in the inoculated leaves and inoculated N. glutinosa produced mosaic and systemic necrosis in the inoculated leaves after 7 days inoculation, respectively, which were consistent with symptoms caused by TSWV (2). To confirm further TSWV-AT1 infection, reverse transcription (RT)-PCR was performed using the One-Step RT-PCR (Invitrogen, Carlsbad, CA) with TSWV-specific primers, TSWV-NCP-For and TSWV-NCP-Rev (3), designed to amplify a 777-bp cDNA of the nucleocapsid protein (NCP) gene. Total RNAs from naturally infected B. suaveolens, symptomatic C. annuum, and N. glutinosa were extracted using RNeasy Plant Mini Kit (Qiagen, Valencia, CA). Total RNAs obtained from a Korean isolate of TSWV (Accession No. JF730744) and healthy B. suaveolens were used as positive and negative controls, respectively. The expected size of the RT-PCR product was amplified from symptomatic B. suaveolens, C. annuum, and N. glutinosa but not from healthy leaves of B. suaveolens. The amplified RT-PCR product from TSWV-AT1 was directly sequenced using BigDye Termination kit (Applied Biosystems, Foster City, CA). Multiple alignment of the TSWV-AT1 NCP sequence (AB910533) with NCP sequences of other TSWV isolates using MEGA5 software (4) revealed 99.0% aa identity with an Korean TSWV isolate (AEB33895) originating from tomato. These results provide additional confirmation of TSWV-AT1 infection. It is known that high-value ornamentals may act also as reservoirs for TSWV that can infect other ornamentals and cultivated crops, because TSWV has a very broad host range (2). Elaborate inspections for TSWV and other viruses are necessary for production of healthy B. suaveolens, since the popularity and economic importance of this ornamental plant is increasing. To our knowledge, this is the first report of TSWV in B. suaveolens in Korea. References: (1) Anonymous. OEPP/EPPO Bull. 34:271, 2004. (2) G. Parrella et al. J. Plant Pathol. 85:227, 2003. (3) B.-N. Chung et al. Plant Pathol. J. 28:87, 2012. (4) K. Tamura et al. Mol. Biol. Evol. 28:2731, 2011.
RESUMO
Catharanthus roseus, commonly known as Madagascar rosy periwinkle (also called vinca), is a tropical perennial herb of the family Apocyanaceae. Periwinkle is a bedding plant widely used in Korea because of its drought tolerance, low maintenance, and varied flower colors. In May 2013, virus-like foliar symptoms, including a mosaic with malformation of leaves, were observed on a periwinkle plant in a greenhouse located in Chonbuk Province, Korea. Cucumber mosaic virus (CMV) was identified in the symptomatic plant by serological testing for the presence of CMV coat protein (CP) with an immune-strip kit developed by our laboratory. The presence of CMV was confirmed by serological detection with a commercially available double-antibody sandwich (DAS)-ELISA kit (Agdia, Elkhart, IN). Sap from the serologically positive sample was mechanically inoculated to test plants using 10 mM phosphate buffer (pH 7.0). The virus (named CMV-Vin) caused necrotic local lesions on Chenopodium amaranticolor at 5 days-post-inoculation (dpi), while mild to severe mosaic was observed in Capsicum annuum, Cucumis sativus, Cucurbita pepo 'Cheonggobong,' Nicotiana glutinosa, N. tabacum'Samsun NN,' Physalis angulate, and Solanum lycopersicum 'Pink-Top' 10 to 14 dpi. Examination of the inoculated plant leaves by DAS-ELISA and electron microscopy (leaf dips) showed positive reactions to CMV and the presence of spherical virions ~28 nm in diameter, respectively. To verify whether CMV was the causal agent for the disease symptoms observed in naturally infected periwinkle, virus-free periwinkle (10 plants) was mechanically inoculated by sap from local lesions on C. amaranticolor inoculated with CMV-Vin. At 6 weeks after inoculation, all plants produced systemic mosaic and distortion of leaves, resulting in strong DAS-ELISA reactions for CMV, whereas mock-inoculated periwinkle plants remained symptomless and virus-free. The presence of CMV-Vin in all naturally infected and mechanically inoculated plants was further verified by reverse transcription (RT)-PCR. Total RNAs were extracted with a RNeasy Plant Mini Kit (Qiagen, Valencia, CA) and RT-PCR was carried out with the One-Step RT-PCR Kit (Invitrogen, Carlsbad, CA) using a pair of primers, CMVCPFor and CMVCPRev (1), which amplified the entire CP gene. RT-PCR products (657 bp) were obtained from all naturally infected and mechanically inoculated plants as well as from a positive control (viral RNAs from virions), but not from healthy tissues. The amplified RT-PCR products were directly sequenced using BigDye Termination kit (Applied Biosystems, Foster City, CA). Multiple alignment of the CMV-Vin CP sequence (Accession No. AB910598) with CP sequences of other CMV isolates using MEGA5 software revealed that 91.8 to 99.0% and 71.0 to 73.0% identities to those of CMV subgroup I and subgroup II, respectively. These results provide additional confirmation of CMV-Vin infection. Being perennial, periwinkle plants could serve as a reservoir for CMV to infect other ornamentals and cultivated crops (2). To our knowledge, this is the first report of CMV infection on periwinkle in Korea. References: (1) S. K. Choi et al. Virus Res. 158:271, 2011. (2) P. Palukaitis et al. Adv. Virus. Res. 41:281, 1992.
RESUMO
African violet (Saintpaulia ionantha) is an ornamental species of the family Gesneriaceae and is characterized by fleshy leaves and colorful flowers. This popular, exotic ornamental, originally from Kenya and Tanzania, is vegetatively produced from cutting and tissue culture (1). In May 2013, virus-like foliar symptoms, including a mosaic with dark green islands and chlorosis surrounding the veins, were observed on an African violet plant in a greenhouse located in Icheon, Korea. Cucumber mosaic virus (CMV) was identified in the symptomatic plant by serological testing for the presence of CMV coat protein (CP) with a commercial immunostrip kit (Agdia, Elkhart, IN). The presence of CMV was confirmed by serological detection with a commercially available double-antibody sandwich (DAS)-ELISA kit (Agdia). Sap from the serologically positive sample was mechanically inoculated to test plants using 10 mM phosphate buffer (pH 7.0). The virus (named CMV-AV1) caused necrotic local lesions on Chenopodium amaranticolor at 5 days post-inoculation (dpi), while mild to severe mosaic was observed in Nicotiana glutinosa, N. tabacum 'Samsun NN,' Cucurbita pepo 'Super-Top,' Physalis angulate, and Solanum lycopersicum 'Unicorn' 10 to 14 dpi. Examination of the inoculated plant leaves by DAS-ELISA and electron microscopy (leaf dips) showed positive reactions to CMV and the presence of spherical virions â¼28 nm in diameter, respectively. To verify whether CMV-AV1 is the cause of disease symptoms observed in African violet, virus-free African violet (10 plants) was mechanically inoculated by sap from local lesions on C. amaranticolor inoculated with CMV-AV1. At 8 weeks after inoculation, all plants produced systemic mosaic and chlorosis surrounding veins, resulting in strong DAS-ELISA reactions for CMV, whereas mock-inoculated African violet plants remained symptomless and virus-free. The presence of CMV-AV1 in all naturally infected and mechanically inoculated plants was further verified by reverse transcription (RT)-PCR. Total RNAs were extracted with the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany), according to the manufacturer's instructions. RT-PCR was carried out with the One-Step RT-PCR Kit (Invitrogen, Carlsbad, CA) using a pair of primers, CPTALL3 and CPTALL5 (2), amplifying the entire CP gene and part of an intergenic region and 3'-noncoding region of CMV RNA3. RT-PCR products (960 bp) were obtained from all naturally infected and mechanically inoculated plants as well as from positive control (viral RNAs from virions), but not from healthy tissues. The amplified RT-PCR products were purified with QIAquick PCR Purification Kit (Qiagen) and sequenced using BigDye Termination kit (Applied Biosystems, Foster City, CA). Multiple alignment of the CMV-AV1 CP sequence (Accession No. AB842275) with CP sequences of other CMV isolates using MEGA5 software revealed that 91.8 to 99.0% and 71.0 to 73.0% identities to those of CMV subgroup I and subgroup II, respectively. These results provide additional confirmation of CMV-AV1 infection. CMV may pose a major threat for production of African violet since the farming of African violet plants is performed using the vegetative propagation of the African violet leaves in Korea. In particular, mosaic and chlorosis symptoms in African violet cause damage to ornamental quality of African violet. To our knowledge, this is the first report of CMV infection of African violet in the world. References: (1) S. T. Baatvik. Fragm. Flor. Geobot. Suppl. 2:97, 1993. (2) S. K. Choi et al. J. Virol. Methods 83:67, 1999.
RESUMO
Cherry necrotic rusty mottle virus (CNRMV), an unassigned member in the family Betaflexiviridae, has been reported in sweet cherry in North America, Europe, New Zealand, Japan, China, and Chile. The virus causes brown, angular necrotic spots, shot holes on the leaves, gum blisters, and necrosis of the bark in several cultivars (1). During the 2012 growing season, 154 sweet cherry trees were tested for the presence of CNRMV by RT-PCR. Samples were randomly collected from 11 orchards located in Gyeonggi and Gyeongsang provinces in Korea. RNA was extracted from leaves using the NucliSENS easyMAG system (bioMérieux, Boxtel, The Netherlands). The primer pair CGRMV1/2 (2) was used to amplify the coat protein region of CNRMV. Although none of the collected samples showed any notable symptoms, CNRMV PCR products of the expected size (949 bp) were obtained from three sweet cherry samples from one orchard in Gyeonggi province. The PCR products were cloned into a pGEM-T easy vector (Promega, Madison, WI) and sequenced. BLAST analyses of the three Korean sequences obtained (GenBank Accession Nos. AB822635, AB822636, and AB822637) showed 97% nucleotide sequence identity with a flowering cherry isolate from Japan (EU188439), and shared 98.8 to 99.6% nucleotide and 99.6 to 100% amino acid similarities to each other. The CNRMV positive samples were also tested for Apple chlorotic leaf spot virus (ACLSV), Cherry mottle leaf virus (CMLV), Cherry rasp leaf virus (CRLV), Cherry leafroll virus (CLRV), Cherry virus A (CVA), Little cherry virus 1 (LChV-1), Prune dwarf virus (PDV), and Prunus necrotic ringspot virus (PNRSV) by RT-PCR. One of the three CNRMV-positive samples was also infected with CVA. To confirm CNRMV infection by wood indexing, Prunus serrulata cv. Kwanzan plants were graft-inoculated with chip buds from the CNRMV-positive sweet cherry trees. At 3 to 4 weeks post-inoculation, the Kwanzan plants showed quick decline with leaves wilting and dying; CNRMV infection of the indicators was confirmed by RT-PCR. To our knowledge, this is the first report of CNRMV infection of sweet cherry trees in Korea. Screening for CNRMV in propagation nurseries should minimize spread of this virus within Korea. References: (1) R. Li and R. Mock. Arch. Virol. 153:973, 2008. (2) R. Li and R. Mock. J. Virol. Methods 129:162, 2005.
RESUMO
We measure the branching fraction of B- â τ- ν(τ) using the full Υ(4S) data sample containing 772×10(6) BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. Events with BB pairs are tagged by reconstructing one of the B mesons decaying into hadronic final states, and B- â τ- ν(τ) candidates are detected in the recoil. We find evidence for B- â τ- ν(τ) with a significance of 3.0 standard deviations including systematic errors and measure a branching fraction B(B- â τ- ν(τ))=[0.72(-0.25)(+0.27)(stat)±0.11(syst)]×10(-4).
Assuntos
Partículas Elementares , Física Nuclear/métodos , Teoria QuânticaRESUMO
We report the results of a high-statistics search for H dibaryon production in inclusive Υ(1S) and Υ(2S) decays. No indication of an H dibaryon with a mass near the M(H)=2m(Λ) threshold is seen in either the HâΛpπ(-) or ΛΛ decay channels and 90% confidence level branching-fraction upper limits are set that are between one and two orders of magnitude below the measured branching fractions for inclusive Υ(1S) and Υ(2S) decays to antideuterons. Since Υ(1S,2S) decays produce flavor-SU(3)-symmetric final states, these results put stringent constraints on H dibaryon properties. The results are based on analyses of 102 million Υ(1S) and 158 million Υ(2S) events collected with the Belle detector at the KEKB e(+)e(-) collider.
RESUMO
We report the first observations of the spin-singlet bottomonium states h(b)(1P) and h(b)(2P). The states are produced in the reaction e(+)e(-)âh(b)(nP)π(+)π(-) using a 121.4 fb(-1) data sample collected at energies near the Υ(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We determine M[h(b)(1P)]=(9898.2(-1.0-1.1)(+1.1+1.0)) MeV/c(2) and M[h(b)(2P)]=(10,259.8±0.6(-1.0)(+1.4)) MeV/c(2), which correspond to P-wave hyperfine splittings ΔM(HF)=(+1.7±1.5) and (+0.5(-1.2)(+1.6)) MeV/c(2), respectively. The significances of the h(b)(1P) and h(b)(2P) are 5.5σ and 11.2σ, respectively. We find that the production of the h(b)(1P) and h(b)(2P) is not suppressed relative to the production of the Υ(1S), Υ(2S), and Υ(3S).
Assuntos
Partículas Elementares , Teoria Quântica , Análise Espectral , TermodinâmicaRESUMO
We search for CP violation in Cabibbo-suppressed charged D meson decays by measuring the difference between the CP-violating asymmetries for the Cabibbo-suppressed decays D(±)âK(+)K(-)π(±) and the Cabibbo-favored decays D(s)(±)âK(+)K(-)π(±) in the K(+)K(-) mass region of the Ï resonance. Using 955 fb(-1) of data collected with the Belle detector, we obtain A(CP)(D+âÏπ+)=(+0.51±0.28±0.05)%. The measurement improves the sensitivity of previous searches by more than a factor of 5. We find no evidence for direct CP violation.
RESUMO
We observe evidence for CP violation in the decay D+ â K(S)(0)π+ using a data sample with an integrated luminosity of 977 fb(-1) collected by the Belle detector at the KEKB e+ e- asymmetric-energy collider. The CP asymmetry in the decay is measured to be (-0.363±0.094±0.067)%, which is 3.2 standard deviations away from zero, and is consistent with the expected CP violation due to the neutral kaon in the final state.
RESUMO
We report a measurement of the CP-violation parameter sin2φ1 at the Υ(5S) resonance using a new tagging method, called "B-π tagging." In Υ(5S) decays containing a neutral B meson, a charged B, and a charged pion, the neutral B is reconstructed in the J/ψK(S)(0) CP-eigenstate decay channel. The initial flavor of the neutral B meson at the moment of the Υ(5S) decay is opposite to that of the charged B and may thus be inferred from the charge of the pion without reconstructing the charged B. From the asymmetry between B-π(+) and B-π(-) tagged J/ψK(S)(0) yields, we determine sin2φ1=0.57±0.58(stat)±0.06(syst). The results are based on 121 fb(-1) of data recorded by the Belle detector at the KEKB e(+)e(-) collider.
RESUMO
We report the first evidence for the η(b)(2S) using the h(b)(2P)âη(b)(2S)γ transition and the first observation of the h(b)(1P)âη(b)(1S)γ and h(b)(2P)âη(b)(1S)γ transitions. The mass and width of the η(b)(1S) and η(b)(2S) are measured to be m(η(b)(1S))=(9402.4±1.5±1.8) MeV/c(2), m(η(b)(2S))=(9999.0±3.5(-1.9)(+2.8)) MeV/c(2), and Γ(η(b)(1S))=(10.8(-3.7-2.0)(+4.0+4.5)) MeV. We also update the h(b)(1P) and h(b)(2P) mass measurements. We use a 133.4 fb(-1) data sample collected at energies near the Υ(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider.
Assuntos
Física Nuclear/métodos , Teoria Quântica , FótonsRESUMO
We report the observation of two narrow structures in the mass spectra of the π(±)Υ(nS) (n=1, 2, 3) and π(±)h(b)(mP) (m=1, 2) pairs that are produced in association with a single charged pion in Υ(5S) decays. The measured masses and widths of the two structures averaged over the five final states are M(1)=(10,607.2±2.0) MeV/c2, Γ(1)=(18.4±2.4) MeV, and M(2)=(10,652.2±1.5) MeV/c2, Γ(2)=(11.5±2.2) MeV. The results are obtained with a 121.4 fb(-1) data sample collected with the Belle detector in the vicinity of the Υ(5S) resonance at the KEKB asymmetric-energy e+ e- collider.
Assuntos
Partículas Elementares , Teoria QuânticaRESUMO
The processes γγ â ωÏ, ÏÏ, and ωω are measured using an 870 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. Production of vector meson pairs is clearly observed and their cross sections are measured for masses that range from threshold to 4.0 GeV. In addition to signals from well established spin-zero and spin-two charmonium states, there are resonant structures below charmonium threshold, which have not been previously observed. We report a spin-parity analysis for the new structures and determine the products of the η(c), χ(c0), and χ(c2) two-photon decay widths and branching fractions to ωÏ, ÏÏ, and ωω.
RESUMO
Nanocrystalline surface layer up to 84 microm in thick is produced on a specimen made of Al6061-T6 alloy by means of surface treatment called ultrasonic nanocrystalline surface modification (UNSM) technique. The refined grain size is produced in the top-layer and it is increased with increasing depth from the top surface. Vickers microhardness measurement for each nanocrystalline surface layer is performed and measurement results showed that the microhardness is increased from 116 HV up to 150 HV, respectively. In this study, fatigue behavior of Al6061-T6 alloy was studied up to 10(7)-10(9) cycles by using a newly developed ultrasonic fatigue testing (UFT) rig. The fatigue results of the UNSM-treated Al6061-T6 alloy specimens were compared with those of the untreated specimens. The microstructure of the untreated and UNSM-treated specimens was characterized by means of scanning electron microscopey (SEM) and transmission electron microscopey (TEM).
RESUMO
National surveillance for bovine spongiform encephalopathy (BSE) began in the Republic of Korea (ROK) in 1996. Surveillance programmes changed overtime to comply with the guidelines of the World Organisation for Animal Health (OIE). Bovine spongiform encephalopathy was designated as a notifiable disease in 1997. From July 2008, the BSE surveillance programme was intensified to test cattle in designated high-risk populations more effectively. New measures included the compulsory testing of all non-ambulatory cattle at abattoirs, and encouraging the testing of all dead cattle examined and recorded under the Mutual Aid Insurance Scheme (fallen stock). In addition, there was a vigorous search for animals suspected of being clinically infected. As a result, a total of 426,919 OIE points were achieved over a period of seven consecutive years to the end of October 2009. This enabled the submission of a successful application to the OIE in 2010 for recognition of the ROK's BSE disease status as being one of controlled risk, in accordance with Chapter 11.5. of the OIE Terrestrial Animal Health Code.