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1.
Open Biol ; 11(10): 210213, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34637655

RESUMEN

The etiopathogenesis of COVID-19 and its differential geographic spread suggest some populations are apparently 'less affected' through many host-related factors that involve angiotensin-converting enzyme 2 (ACE2) protein, which is also the entry receptor for SARS-CoV-2. The role of ACE2 has been well studied in COVID-19 but not in the context of malaria and COVID-19. We have previously suggested how malaria might intersect with COVID-19 through ACE2 mutation and here we evaluate the currently available data that could provide a link between the two diseases. Based on the existing global and Indian data on malaria, COVID-19 and the suggested ACE2 mutation, the association could not be examined robustly, neither accepting nor refuting the suggested hypothesis. We strongly recommend targeted evaluation of this hypothesis through carefully designed robust molecular epidemiological studies.


Asunto(s)
Enzima Convertidora de Angiotensina 2/genética , COVID-19/complicaciones , COVID-19/epidemiología , Malaria/complicaciones , Malaria/epidemiología , Alelos , Predisposición Genética a la Enfermedad , Variación Genética , Geografía , Salud Global , Humanos , India , Mutación
2.
Neurobiol Learn Mem ; 175: 107314, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32961277

RESUMEN

A diverse array of neurometabolic coupling mechanisms exist within the brain to ensure that sufficient metabolite availability is present to meet both acute and chronic energetic demands. Excitatory synaptic activity, which produces the majority of the brain's energetic demands, triggers a rapid metabolic response including a characteristic shift towards aerobic glycolysis. Herein, astrocytically derived lactate appears to serve as an important metabolite to meet the extensive metabolic needs of activated neurons. Despite a wealth of literature characterizing lactate's role in mediating these acute metabolic needs, the extent to which lactate supports chronic energetic demands of neurons remains unclear. We hypothesized that synaptic potentiation, a ubiquitous brain phenomenon that can produce chronic alterations in synaptic activity, could necessitate persistent alterations in brain energetics. In freely-behaving rats, we induced long-term potentiation (LTP) of synapses within the dentate gyrus through high-frequency electrical stimulation (HFS) of the medial perforant pathway. Before, during, and after LTP induction, we continuously recorded extracellular lactate concentrations within the dentate gyrus to assess how changes in synaptic strength alter local glycolytic activity. Synaptic potentiation 1) altered the acute response of extracellular lactate to transient neuronal activation as evident by a larger initial dip and subsequent overshoot and 2) chronically increased local lactate availability. Although synapses were potentiated immediately following HFS, observed changes in lactate dynamics were only evident beginning ~24 h later. Once observed, however, both synaptic potentiation and altered lactate dynamics persisted for the duration of the experiment (~72 h). Persistent alterations in synaptic strength, therefore, appear to be associated with metabolic plasticity in the form of persistent augmentation of glycolytic activity.


Asunto(s)
Giro Dentado/metabolismo , Ácido Láctico/metabolismo , Potenciación a Largo Plazo/fisiología , Plasticidad Neuronal , Animales , Estimulación Eléctrica , Espacio Extracelular/metabolismo , Glucólisis , Vía Perforante , Ratas
3.
Neurol India ; 64(5): 973-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27625241

RESUMEN

BACKGROUND: Radiosurgery seems to be a very appealing option for patients having a small petrous apex meningioma and presenting with trigeminal neuralgia, presumably because of the lower risk and cost involved. The aim of this study was to analyze the results of our surgical series of petrous apex meningioma presenting with trigeminal neuralgia, and to determine the efficacy of neurosurgical treatment with regard to pain control. The procedure-related complication and morbidity rates were also evaluated. MATERIALS AND METHODS: This is a retrospective study of 17 patients with a small (<3 cm) petrous apex meningioma. The included patients were refractory to medical treatment for trigeminal neuralgia and were deemed as surgical candidates. Postoperatively, the patients were assessed for pain relief according to the Barrow Neurological Institute (BNI) scale. A P value of less than 0.05 was considered significant. Magnetic resonance imaging was also performed after 6 weeks to assess the radicality of resection. RESULTS: In a median follow-up of approximately 2 years, the study showed that 14 of the 17 (82.4%) patients had complete pain relief, with very low morbidity and no mortality, and 100% tumor control. According to the Barrow Neurological Institute (BNI) scale for the assessment of postoperative pain relief, 52.9, 23.5, 5.9, 11.8, and 5.9% of patients had grades I, II, IIIa, IIIb, and IV in terms of their pain relief, respectively. CONCLUSIONS: In our population of patients, surgery proved to be successful in providing symptomatic relief, with low morbidity and no mortality, and was comparable with other studies involving the minimally invasive modalities. However, these results warrant further follow-up, with recruitment of more patients, to demonstrate whether or not, surgery should be the primary choice of treatment in this subgroup of patients.


Asunto(s)
Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Radiocirugia/métodos , Enfermedades del Nervio Trigémino/etiología , Humanos , Imagen por Resonancia Magnética , Dimensión del Dolor , Hueso Petroso , Estudios Retrospectivos
4.
Neurotoxicology ; 55: 154-159, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27293183

RESUMEN

Tauopathies are a class of neurodegenerative diseases associated with the pathological aggregation of the tau protein in the human brain. The best known of these illnesses is Alzheimer's disease (AD); a disease where the microtubule associated protein tau (MAPT) becomes hyperphosphorylated (lowering its binding affinity to microtubules) and aggregates within neurons in the form of neurofibrillary tangles (NFTs). In this paper we examine whether environmental factors play a significant role in tau pathogenesis. Our studies were conducted in a double mutant mouse model that expressed the human tau gene and lacked the gene for murine tau. The human tau mouse model was tested for the transgene's ability to respond to an environmental toxicant. Pups were developmentally exposed to lead (Pb) from postnatal day (PND) 1-20 with 0.2% Pb acetate. Mice were then sacrificed at PND 20, 30, 40 and 60. Protein and mRNA levels for tau and CDK5 as well as tau phosphorylation at Ser396 were determined. In addition, the potential role of miRNA in tau expression was investigated by measuring levels of miR-34c, a miRNA that targets the mRNA for human tau, at PND20 and 50. The expression of the human tau transgene was altered by developmental exposure to Pb. This exposure also altered the expression of miR-34c. Our findings are the first of their kind to test the responsiveness of the human tau gene to an environmental toxicant and to examine an epigenetic mechanism that may be involved in the regulation of this gene's expression.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Plomo/farmacología , Proteínas tau/genética , Proteínas tau/metabolismo , Animales , Animales Recién Nacidos , Quinasa 5 Dependiente de la Ciclina/genética , Quinasa 5 Dependiente de la Ciclina/metabolismo , Relación Dosis-Respuesta a Droga , Regulación del Desarrollo de la Expresión Génica/genética , Genotipo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Ratones , Ratones Transgénicos , MicroARNs/genética , MicroARNs/metabolismo , Fosforilación/efectos de los fármacos , ARN Mensajero/metabolismo
5.
Indian J Med Microbiol ; 32(1): 72-4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24399394

RESUMEN

Trichosporon species are widely distributed in nature and can occasionally belong to the human microbiota. For many years, Trichosporon beigelii, the only species of this genus, was found as the aetiological agent of superficial skin infection called white piedra. However, many cases of invasive trichosporonosis caused by different newly delineated species of Trichosporon have been published in increasing numbers in recent past years, especially in immunocompromised persons. We report a rare case of fungemia due to Trichosporon mucoides in a diabetes mellitus patient, which will add to the emerging list of trichosporonosis infections.


Asunto(s)
Fungemia/diagnóstico , Trichosporon/aislamiento & purificación , Tricosporonosis/diagnóstico , Complicaciones de la Diabetes , Fungemia/microbiología , Fungemia/patología , Humanos , Masculino , Persona de Mediana Edad , Tricosporonosis/microbiología , Tricosporonosis/patología
6.
J Postgrad Med ; 59(3): 196-202, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24029197

RESUMEN

Tuberculosis (TB) is responsible for 1.4 million deaths annually. Wide-spread misuse of anti-tubercular drugs over three decades has resulted in emergence of drug resistant TB including multidrug-resistant TB and extensively drug-resistant TB globally. Accurate and rapid diagnosis of drug-resistant TB is one of the paramount importance for instituting appropriate clinical management and infection control measures. The present article provides an overview of the various diagnostic options available for drug resistant TB, by searching PubMed for recent articles. Rapid phenotypic tests still requires days to weeks to obtain final results, requiring biosafety and quality control measures. For newly developed molecular methods, infrastructure, training and quality assurance should be followed. Successful control of drug resistant TB globally will depend upon strengthening TB control programs, wider access to rapid diagnosis and provision of effective treatment. Therefore, political and fund provider commitment is essential to curb the spread of drug resistant TB.


Asunto(s)
Técnicas de Tipificación Bacteriana , Tuberculosis Extensivamente Resistente a Drogas/diagnóstico , Pruebas de Sensibilidad Microbiana/métodos , Algoritmos , Tuberculosis Extensivamente Resistente a Drogas/prevención & control , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa
7.
J Postgrad Med ; 59(2): 110-4, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23793311

RESUMEN

BACKGROUND: Human immunodeficiency virus (HIV) counseling and testing (HCT) conducted at integrated counseling and testing centers (ICTCs) is an entry point, cost-effective intervention in preventing transmission of HIV. OBJECTIVES: To study the prevalence of HIV among ICTC attendees, sociodemographic characteristics, and risk behaviors of HIV-seropositive clients. MATERIALS AND METHODS: It was hospital record-based cross-sectional study of 26,518 registered ICTC clients at a tertiary care hospital in Ganjam district, Odisha, India over a 4-year period from January 2009 to September 2012. RESULTS: A total of 1732 (7.5%) out of 22,897 who were tested for HIV were seropositive. Among HIV-seropositives, 1138 (65.7%) were males, while 594 (34.3%) were females. Majority (88.3%) of seropositives were between the age group of 15-49 years. Client-initiated HIV testing (12.1%) was more seropositive compared to provider-initiated (2.9%). Among discordant couples, majority (95.5%) were male partner/husband positive and female partner/wife negative. Positives were more amongst married, less educated, low socioeconomic status, and outmigrants (P<0.0001). Risk factors included heterosexual promiscuous (89.3%), parent-to-child transmission 5.8%, unknown 3.1%, infected blood transfusion 0.8%, homosexual 0.5%, and infected needles (0.5%). CONCLUSIONS: There is need to encourage activities that promote HCT in all health facilities. This will increase the diagnosis of new HIV cases. The data generated in ICTC provide an important clue to understand the epidemiology in a particular geographic region and local planning for care and treatment of those infected with HIV and preventive strategies for those at risk especially married, young adults, and outmigrants to reduce new infections.


Asunto(s)
Servicios de Diagnóstico/estadística & datos numéricos , Consejo Dirigido/estadística & datos numéricos , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Adolescente , Adulto , Estudios Transversales , Femenino , Infecciones por VIH/epidemiología , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Estudios Seroepidemiológicos , Distribución por Sexo , Conducta Sexual , Factores Socioeconómicos , Atención Terciaria de Salud , Adulto Joven
8.
Indian J Med Microbiol ; 31(1): 82-4, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23508438

RESUMEN

Dipylidiasis is a zoonotic parasitic infestation caused by the dog tapeworm Dipylidium caninum. Human dipylidiasis has been rarely reported in English literature. Young children are mostly at risk of acquiring the infection due to their close association with dogs and cats. We report a rare case of Dipylidium caninum infection in a 4 year old male child. The diagnosis was based on microscopic examination of stool. Confirmation of the proglottid segments was done by histopathological examination. To the best of our knowledge this is the first human case of Dipylidium caninum reported from this part of the country.


Asunto(s)
Cestodos/aislamiento & purificación , Infecciones por Cestodos/diagnóstico , Infecciones por Cestodos/patología , Animales , Antihelmínticos/uso terapéutico , Infecciones por Cestodos/parasitología , Preescolar , Heces/parasitología , Histocitoquímica , Humanos , Masculino , Microscopía , Parasitología
9.
J Microsc ; 249(1): 26-35, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23126369

RESUMEN

The systematic misindexing caused by pseudo-symmetry Kikuchi diffraction patterns in automated Electron Backscatter Diffraction analysis has been studied in a 9Cr-1Mo ferritic steel. Grains with its [1 1 1] directed towards detector centre were found to be prone to misindexing, and the solutions exhibit a relative orientation of ±30° and 60° about the common [1 1 1] axis (as compared to the true orientation). Fictitious boundaries were detected within such grains, which satisfy the Σ3 or Σ13b type coincidence site lattice boundary criteria. Misindexing rate was reduced with more than six detected bands, but 30° rotated solution was comparatively more persistent, as the additional bands of (3 1 0)-type exhibited a nearly good pattern match. Increase in detector collection angle to 0.96 sr or number of detected bands to nine were found to be beneficial in preventing the misindexing problem.

10.
Mol Ecol Resour ; 12(4): 779-81, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22642264

RESUMEN

This article documents the addition of 171 microsatellite marker loci and 27 pairs of single nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Bombus pauloensis, Cephalorhynchus heavisidii, Cercospora sojina, Harpyhaliaetus coronatus, Hordeum vulgare, Lachnolaimus maximus, Oceanodroma monteiroi, Puccinia striiformis f. sp. tritici, Rhea americana, Salmo salar, Salmo trutta, Schistocephalus solidus, Sousa plumbea and Tursiops aduncus. These loci were cross-tested on the following species: Aquila heliaca, Bulweria bulwerii, Buteo buteo, Buteo swainsoni, Falco rusticolus, Haliaeetus albicilla, Halobaena caerulea, Hieraaetus fasciatus, Oceanodroma castro, Puccinia graminis f. sp. Tritici, Puccinia triticina, Rhea pennata and Schistocephalus pungitii. This article also documents the addition of 27 sequencing primer pairs for Puffinus baroli and Bulweria bulwerii and cross-testing of these loci in Oceanodroma castro, Pelagodroma marina, Pelecanoides georgicus, Pelecanoides urinatrix, Thalassarche chrysostoma and Thalassarche melanophrys.


Asunto(s)
Bases de Datos Genéticas , Repeticiones de Microsatélite , Polimorfismo de Nucleótido Simple , Ecología , Marcadores Genéticos
11.
J Hazard Mater ; 192(3): 1580-8, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21802849

RESUMEN

A novel polymeric flocculant based on polyacrylamide grafted carboxymethyl guar gum (CMG-g-PAM) has been synthesised by grafting polyacrylamide chains onto CMG backbone using conventional redox grafting and microwave assisted grafting methods. Under optimum grafting conditions, 82% and 96% grafting efficiencies have been observed in case of conventional and microwave assisted methods respectively. The optimum sample has been characterized using viscometry, spectroscopic analysis, elemental analysis, molecular weight and radius of gyration determination. The flocculation characteristics of grafted and ungrafted polysaccharides have been evaluated in kaolin suspension, municipal sewage wastewater and decolourization efficiency of a dye solution (methylene blue). It is evident from results that CMG-g-PAM synthesised by microwave assisted grafting method is showing best flocculation characteristics.


Asunto(s)
Resinas Acrílicas/química , Floculación , Galactanos/química , Mananos/química , Gomas de Plantas/química , Colorantes/química , Caolín/química , Espectroscopía de Resonancia Magnética/métodos , Microondas , Peso Molecular , Oxidación-Reducción , Polímeros/química , Aguas del Alcantarillado , Solventes , Espectrofotometría/métodos , Viscosidad , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
12.
Phys Rev Lett ; 104(23): 231801, 2010 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-20867227

RESUMEN

First observations of the B(s)(0) → D(s)(*-) π+, B(s)(0) → D(s)(-) ρ+ and B(s)(0) → D(s)(*-) ρ+ decays are reported together with measurements of their branching fractions: B(B(s)(0) → D(s)(*-) π+) = [2.4(-0.4)(+0.5)(stat) ± 0.3(syst) ± 0.4(f(s))]×10(-3), B(B(s)(0) → D(s)(-) ρ+) = [8.5(-1.2)(+1.3)(stat) ± 1.1(syst) ± 1.3(f(s))]×10(-3) and B(B(s)(0) → D(s)(*-) ρ+) = [11.9(-2.0)(+2.2)(stat) ± 1.7(syst) ± 1.8(f(s))]×10(-3) (f(s) = N(B(s)(*) B(s)(*))/N(bb)). From helicity-angle distributions, we measured the longitudinal polarization fraction in B(s)(0) → D(s)(*-) ρ+ decays to be f(L)(B(s)(0) → D(s)(*-) ρ+) = 1.05(-0.10)(+0.08)(stat)(-0.04)(+0.03)(syst). These results are based on a 23.6 fb(-1) data sample collected at the Υ(5S) resonance with the Belle detector at the KEKB e+ e- collider.


Asunto(s)
Partículas Elementales , Teoría Cuántica
13.
Phys Rev Lett ; 105(9): 091801, 2010 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-20868151

RESUMEN

We search for dimuon decays of a low mass particle in the decays B0→K*0 X and B0→ρ0 X using a data sample of 657×10(6)BB events collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. We find no evidence for such a particle in the mass range from 212 MeV/c2 to 300 MeV/c2 for lifetimes below 10(-12) s, and set upper limits on its branching fractions. In particular, we search for a particle with a mass of 214.3 MeV/c2 reported by the HyperCP experiment, and obtain upper limits on the products B(B0→K*0 X)×B(X→µ+ µ- )<2.26(2.27)×10(-8) and B(B0→ρ0 X)×B(X→µ+ µ-)<1.73(1.73)×10(-8) at 90% C.L. for a scalar (vector) X particle.


Asunto(s)
Modelos Químicos , Nanopartículas/química , Física Nuclear , Algoritmos , Transferencia de Energía , Iones , Aceleradores de Partículas
14.
Phys Rev Lett ; 104(2): 021801, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20366585

RESUMEN

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.

15.
Phys Rev Lett ; 105(20): 201802, 2010 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-21231220

RESUMEN

We have made the first observation of B(s)(0)→D(s)(*)+ D(s)(*)- decays using 23.6 fb(-1) of data recorded by the Belle experiment running on the Υ(5S) resonance. The branching fractions are measured to be B(B(s)(0)→D(s)+ D(s)-)=(1.03(-0.32-0.25)(+0.39+0.26))%, B(B(s)(0)→D(s)(*±) D(s)(∓))=(2.75(-0.71)(+0.83)±0.69)%, and B(B(s)(0)→D(s)*+ D(s)*-)=(3.08(-1.04-0.86)(+1.22+0.85))%; the sum is B[B(s)(0)→D(s)(*)+ D(s)(*)-]=(6.85(-1.30-1.80)(+1.53+1.79))%. Assuming B(s)(0)→D(s)(*)+ D(s)(*)- saturates decays to CP-even final states, the branching fraction determines the ratio ΔΓ(s)/cosφ, where ΔΓ(s) is the difference in widths between the two B(s)-B(s) mass eigenstates, and φ is a CP-violating weak phase. Taking CP violation to be negligibly small, we obtain ΔΓ(s)/Γ(s)=0.147(-0.030)(+0.036)(stat)(-0.041)(+0.042)(syst), where Γ(s) is the mean decay width.

17.
Phys Rev Lett ; 102(2): 021801, 2009 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-19257264

RESUMEN

We have studied B_(s);(0)-->D_(s);(-)pi;(+) and B_(s);(0)-->D_(s);(-/+)K;(+/-) decays using 23.6 fb;(-1) of data collected at the Upsilon(5S) resonance with the Belle detector at the KEKB e;(+)e;(-) collider. This highly pure B_(s);(0)-->D_(s);(-)pi;(+) sample is used to measure the branching fraction, B(B_(s);(0)-->D_(s);(-)pi;(+))=[3.67_(-0.33);(+0.35)(stat)-0.42+0.43(syst)+/-0.49(f_(s))]x10;(-3) (f_(s)=N_(B_(s);((*))B[over ]_(s);((*)))/N_(bb[over ])) and the fractions of B_(s);(0) event types at the Upsilon(5S) energy, in particular N_(B_(s);(*)B[over ]_(s);(*))/N_(B_(s);((*))B[over ]_(s);((*)))=(90.1_(-4.0);(+3.8)+/-0.2)%. We also determine the masses M(B_(s);(0))=(5364.4+/-1.3+/-0.7) MeV/c;(2) and M(B_(s);(*))=(5416.4+/-0.4+/-0.5) MeV/c;(2). In addition, we observe B_(s);(0)-->D_(s);(-/+)K;(+/-) decays with a significance of 3.5sigma and measure B(B_(s);(0)-->D_(s);(-/+)K;(+/-))=[2.4_(-1.0);(+1.2)(stat)+/-0.3(syst)+/-0.3(f_(s))]x10;(-4).

18.
Phys Rev Lett ; 101(23): 231801, 2008 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-19113539

RESUMEN

We present the results of a study of the charmless vector-vector decay B0-->omegaK*0 with 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We measure the branching fraction to be B(B0-->omegaK*0) = [1.8+/-0.7(stat)+/-0.3(syst)]x 10(-6) with 3.0sigma significance. We also perform a helicity analysis of the omega and K*0 vector mesons, and obtain the longitudinal polarization fraction fL(B0-->omegaK*0) = 0.56+/-0.29(stat) -0.08(+0.18)(syst). Finally, we measure a large nonresonant branching fraction B[B0-->omegaK+pi(-);M Kpi in(0.755,1.250) GeV/c2] = [5.1+/-0.7(stat)+/-0.7(syst)]x 10(-6) with a significance of 9.5sigma.

19.
Phys Rev Lett ; 101(17): 172001, 2008 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-18999743

RESUMEN

We report a measurement of the exclusive e+ e- -->Lambda+_(c)Lambda-_(c) cross section as a function of center-of-mass energy near the Lambda+_(c)Lambda-_(c) threshold. A clear peak with a significance of 8.2sigma is observed in the Lambda+_(c)Lambda-_(c) invariant mass distribution just above threshold. With an assumption of a resonance origin for the observed peak, a mass and width of M=[4634 (+8)_(-7)(stat)(+5)_(-8)(syst)] MeV/c(2) and Gamma_(tot)=[92 (+40)_(-24)(stat)(+10)_(-21)(syst)] MeV are determined. The analysis is based on a study of events with initial-state-radiation photons in a data sample collected with the Belle detector at the Upsilon(4S) resonance and nearby continuum with an integrated luminosity of 695 fb(-1) at the KEKB asymmetric-energy e+ e- collider.

20.
Phys Rev Lett ; 101(11): 111801, 2008 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-18851272

RESUMEN

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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