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Visualization of Pterygomaxillary Fissure Structure and Shape in CT Image via Non-Linear Perspective Projection. JOURNAL OF MEDICAL IMAGING AND HEALTH INFORMATICS 2021. [DOI: 10.1166/jmihi.2021.3809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The neurologist analyses the brain images to diagnose disease via structure and shape of the part in scanned Medical images such as CT, MRI, and PET. The Medical image segmentation performs less in the regions where no or little contrast, artifacts over the different boundary regions.
The manual process of segmentation shows poor boundary differentiation due to discernibility in shape and location, intra and inter observer reliability. In this paper, we propose dyadic CAT optimization (DCO) algorithm to segment the regions in the brain from CT and MRI image via Non-linear
perspective Foreground and Back Ground projection. The DCO algorithm removes the artifacts in the boundary regions and provide the exact structure and shape of the brain regions. The DCO algorithm shows the region boundary for pterygomaxillary fissure, occipital lobe, vaginal process zygomatic
arch, maxilla and piriform aperture in brain image with high visibility in the regions of inadequately visible boundary and distinguishes the deformable shape. The DCO algorithm applies on 50 images and eight images with complex bone and muscle mass structure for performance evaluation. The
DCO algorithm shows the increased Structural similarity index (SSIM) with 90% accuracy.
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2
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Novel OGBEE-based feature selection and feature-level fusion with MLP neural network for social media multimodal sentiment analysis. Soft comput 2020. [DOI: 10.1007/s00500-020-05049-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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3
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On the importance of field driven single particle processes in short pulse absorption of clusters. Sci Rep 2019; 9:15135. [PMID: 31641204 PMCID: PMC6805859 DOI: 10.1038/s41598-019-51385-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 09/06/2019] [Indexed: 11/09/2022] Open
Abstract
Nano-clusters are acclaimed to be very efficient absorbers of intense femto second light due to dominant collective mechanisms. Enhanced near 100% absorption due to collective linear plasma resonance compared to a small fraction of absorption by unclustered gas was an important drive in nano-plasma studies. Contrary to such perception, we show that if the pulse duration is (<100 fs), absorption is same irrespective of whether the systems are condensed to large clusters or not. So long as there are same number of similar ionizable systems in the focal volume, absorption is the same and such absorption can be accounted for by single particle response to the field and collisional ionization of atoms. Short pulse absorption by the single particle response can be comparable to the linear plasma resonance absorption for smaller clusters.
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4
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Recombination of Protons Accelerated by a High Intensity High Contrast Laser. PHYSICAL REVIEW LETTERS 2018; 121:134801. [PMID: 30312093 DOI: 10.1103/physrevlett.121.134801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Indexed: 06/08/2023]
Abstract
Short pulse, high contrast, intense laser pulses incident onto a solid target are not known to generate fast neutral atoms. Experiments carried out to study the recombination of accelerated protons show a 200 times higher neutralization than expected. Fast neutral atoms can contribute to 80% of the fast particles at 10 keV, falling rapidly for higher energy. Conventional charge transfer and electron-ion recombination in a high density plasma plume near the target is unable to explain the neutralization. We present a model based on the copropagation of electrons and ions wherein recombination far away from the target surface accounts for the experimental measurements. A novel experimental verification of the model is also presented. This study provides insights into the closely linked dynamics of ions and electrons by which neutral atom formation is enhanced.
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5
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Information Use, User, User Needs and Seeking Behaviour: A Review. DESIDOC JOURNAL OF LIBRARY & INFORMATION TECHNOLOGY 2018. [DOI: 10.14429/djlit.38.2.12098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>The studies on the user, user information behaviour, and seeking have been continuing since last 50 years or </span><span>more. Ranganathan’s five laws brought the phrase ‘use’ reordering from preservation. The studies on user and user behaviour with varying characteristics has not changed and still going on to study the impact of ICT and use of electronic resources. Several hidden revelations on users’ approach to information identified by Voigt, types of readers identified by Ranganathan and the ASK model by Belkin have been expounded to visualise the user categories and attributes of the user, user information behaviour and so on. The aim of this paper is only a perspective review of the literature on information user, with an intrinsic scope for some new research possibilities in this area. </span></p></div></div></div>
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A gated Thomson parabola spectrometer for improved ion and neutral atom measurements in intense laser produced plasmas. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:083305. [PMID: 28863677 DOI: 10.1063/1.4998685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ions of high energy and high charge are accelerated from compact intense laser produced plasmas and are routinely analysed either by time of flight or Thomson parabola spectrometry. At the highest intensities where ion energies can be substantially large, both these techniques have limitations. Strong electromagnetic pulse noise jeopardises the arrival time measurement, and a bright central spot in the Thomson parabola spectrometer affects the signal to noise ratio of ion traces that approach close to the central spot. We present a gated Thomson parabola spectrometer that addresses these issues and provides an elegant method to improvise ion spectrometry. In addition, we demonstrate that this method provides the ability to detect and measure high energy neutral atoms that are invariably present in most intense laser plasma acceleration experiments.
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Research contributions of space technology scientists: A scientometric study. COLLNET JOURNAL OF SCIENTOMETRICS AND INFORMATION MANAGEMENT 2017. [DOI: 10.1080/09737766.2017.1312788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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8
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A source to deliver mesoscopic particles for laser plasma studies. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:023301. [PMID: 28249480 DOI: 10.1063/1.4974973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Intense ultrashort laser produced plasmas are a source for high brightness, short burst of X-rays, electrons, and high energy ions. Laser energy absorption and its disbursement strongly depend on the laser parameters and also on the initial size and shape of the target. The ability to change the shape, size, and material composition of the matter that absorbs light is of paramount importance not only from a fundamental physics point of view but also for potentially developing laser plasma sources tailored for specific applications. The idea of preparing mesoscopic particles of desired size/shape and suspending them in vacuum for laser plasma acceleration is a sparsely explored domain. In the following report we outline the development of a delivery mechanism of microparticles into an effusive jet in vacuum for laser plasma studies. We characterise the device in terms of particle density, particle size distribution, and duration of operation under conditions suitable for laser plasma studies. We also present the first results of x-ray emission from micro crystals of boric acid that extends to 100 keV even under relatively mild intensities of 1016 W/cm2.
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N-Chlorosuccinimide-Mediated Oxidative Chlorination of Thiols to Nα -Protected Amino Alkyl Sulfonyl Azides and Their Utility in the Synthesis of Sulfonyl Triazole Acids. Protein Pept Lett 2016; 24:56-63. [PMID: 27894246 DOI: 10.2174/0929866523666161130151218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 11/02/2016] [Accepted: 11/05/2016] [Indexed: 11/22/2022]
Abstract
An efficient oxidative chlorination of thiols to Nα-protected amino alkyl sulfonyl azides is
delineated. The reaction involves in situ generation of sulfonyl chloride employing Nchlorosuccinimide
and tetrabutylammonium chloride-water in acetonitrile, followed by the reaction
with sodium azide. The protocol is simple, straight forward, mild and high yielding. Amino acids
with simple as well as bifunctional side chains were used to obtain Nα-protected amino alkyl sulfonyl
azides. Further, sulfonyl azides were utilized to synthesize unnatural amino acids via
Cu(OAc)2.H2O/2-amino phenol catalyzed Click reaction with propiolic acid.
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10
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N-Chlorosuccinimide-mediated oxidative chlorination of thiols to Nα-protected amino alkyl sulfonyl azides and their utility in the synthesis of sulfonyl triazole acids. Protein Pept Lett 2016:PPL-EPUB-80052. [PMID: 27908261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/22/2016] [Accepted: 11/01/2016] [Indexed: 06/06/2023]
Abstract
An efficient oxidative chlorination of thiols to Nα-protected amino alkyl sulfonyl azides is delineated. The reaction involves in situ generation of sulfonyl chloride employing N-chlorosuccinimide and tetrabutylammonium chloride-water in acetonitrile, followed by the reaction with sodium azide. The protocol is simple, straight forward, mild and high yielding. Amino acids with simple as well as bifunctional side chains were used to obtain Nα-protected amino alkyl sulfonyl azides. Further, sulfonyl azides were utilized to synthesize unnatural amino acids via Cu(OAc)2.H2O/2-amino phenol catalyzed Click reaction with propiolic acid.
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11
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“Thioureidopeptide”: Novel Synthon for the Synthesis of N, N′, N″-Trisubstituted Guanidinopeptide Mimics. Int J Pept Res Ther 2015. [DOI: 10.1007/s10989-015-9496-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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12
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Erratum: Corrigendum: Preferential enhancement of laser-driven carbon ion acceleration from optimized nanostructured surfaces. Sci Rep 2015; 5:13326. [DOI: 10.1038/srep13326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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13
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Abstract
Recently, it has been greatly appreciated that intense light matter interaction is modified due to the nano- and microstructures in the target by--surface plasmons, laser energy localization scattering etc. Extreme laser intensities produce dense plasmas and collective mechanisms generate energetic electrons, ions and hard x-rays. Recently, it is postulated that the anharmonic electron motion, driven by ultrashort, high-intensity laser pulses, provides a universal mechanism for the laser absorption. Here, we provide the first demonstration of anharmonic-resonance-aided high laser-absorption in a biological system. At intensities of ∼ 10¹⁶⁻¹⁸ W/cm², 40 fs pulses excite a plasma formed with E. coli bacteria. The density-inhomogeneities due to the micro- and nanostructures in the bacterial target increase anharmonic resonance (AHR) heating and result in a 10⁴-fold enhancement in the hard x-ray yield compared to plain solid targets. These observations lead to novel high-energy x-ray sources that have implications to lithography, imaging and medical applications.
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14
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Preferential enhancement of laser-driven carbon ion acceleration from optimized nanostructured surfaces. Sci Rep 2015; 5:11930. [PMID: 26153048 PMCID: PMC4495568 DOI: 10.1038/srep11930] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 04/28/2015] [Indexed: 11/20/2022] Open
Abstract
High-intensity ultrashort laser pulses focused on metal targets readily generate hot dense plasmas which accelerate ions efficiently and can pave way to compact table-top accelerators. Laser-driven ion acceleration studies predominantly focus on protons, which experience the maximum acceleration owing to their highest charge-to-mass ratio. The possibility of tailoring such schemes for the preferential acceleration of a particular ion species is very much desired but has hardly been explored. Here, we present an experimental demonstration of how the nanostructuring of a copper target can be optimized for enhanced carbon ion acceleration over protons or Cu-ions. Specifically, a thin (≈0.25 μm) layer of 25–30 nm diameter Cu nanoparticles, sputter-deposited on a polished Cu-substrate, enhances the carbon ion energy by about 10-fold at a laser intensity of 1.2×1018 W/cm2. However, particles smaller than 20 nm have an adverse effect on the ion acceleration. Particle-in-cell simulations provide definite pointers regarding the size of nanoparticles necessary for maximizing the ion acceleration. The inherent contrast of the laser pulse is found to play an important role in the species selective ion acceleration.
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15
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Abstract
Intense laser produced plasmas generate hot electrons which in turn leads to ion acceleration. Ability to generate faster ions or hotter electrons using the same laser parameters is one of the main outstanding paradigms in the intense laser-plasma physics. Here, we present a simple, albeit, unconventional target that succeeds in generating 700 keV carbon ions where conventional targets for the same laser parameters generate at most 40 keV. A few layers of micron sized bacteria coating on a polished surface increases the laser energy coupling and generates a hotter plasma which is more effective for the ion acceleration compared to the conventional polished targets. Particle-in-cell simulations show that micro-particle coated target are much more effective in ion acceleration as seen in the experiment. We envisage that the accelerated, high-energy carbon ions can be used as a source for multiple applications.
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16
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Photoionization of clusters in intense few-cycle near infrared femtosecond pulses. Phys Chem Chem Phys 2014; 16:8721-30. [DOI: 10.1039/c3cp55380a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In this article we present a perspective on the current state of the art in the photoionization of atomic clusters in few-cycle near-infrared laser pulses.
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17
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Anomalous ion charge distribution from cluster nanoplasmas. PHYSICAL REVIEW LETTERS 2013; 111:143401. [PMID: 24138236 DOI: 10.1103/physrevlett.111.143401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Indexed: 06/02/2023]
Abstract
In nearly all the intense laser experiments with nanoclusters, the key observation has been that immense ionization drives highly charged ions to highest energies while low charge ions, if any, have lower kinetic energies. We show experimental measurements that are contrary to this established notion. The active role of outer-ionized electrons in a multicluster interaction is shown to effectively reduce high charge ions to low charge states with no loss of momentum. The role of Rydberg excited clusters, intrinsic in dense cluster ensembles, is identified and a quantitative analysis is shown to comprehensively explain the anomalous charge distribution and ion energies observed in experiments.
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18
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Justice in Global Pandemic Influenza Preparedness: An Analysis Based on the Values of Contribution, Ownership and Reciprocity. Public Health Ethics 2013. [DOI: 10.1093/phe/pht027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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20
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A bright point source of ultrashort hard x-ray pulses using biological cells. OPTICS EXPRESS 2012; 20:5754-5761. [PMID: 22418381 DOI: 10.1364/oe.20.005754] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We demonstrate that the interaction of intense femtosecond light on a plain solid substrate can be substantially altered by a few micron layer coating of bacterial cells, live or dead. Using E. Coli cells, we show that at an intensity of 10(16)W cm(-2), the bremsstraahlung hard x-ray emission (up to 300 keV), is increased by more than two orders of magnitude as compared to a plain glass slab. Particle-in-cell simulations carried out by modeling the bacterial cells as ellipsoidal particles show that the hot electron generation is indeed enhanced by the presence of microstructures. This new methodology should pave way for using microbiological systems of varied shapes to control intense laser produced plasmas for EUV/x-ray generation.
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21
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Atypical presentation of the broken heart syndrome associated with chronic anxiety. JOURNAL OF NEPAL HEALTH RESEARCH COUNCIL 2012; 10:69-72. [PMID: 22929642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The "broken heart syndrome", or Takotsubo cardiomyopathy, is an acute cause of transient left ventricular systolic dysfunction characterized by abrupt onset of chest symptoms, ECG changes and a mild rise in myocardial enzymes mimicking acute myocardial infarction. This condition is more common in postmenopausal women and is typically preceded by an intense emotional or physical stress or an acute illness. A higher prevalence of anxiety disorders in patients with this syndrome have also been reported recently. Apical ballooning with left ventricular akinesis or dyskinesis of distal one-third to two-thirds of the left ventricle in cardiac catheterization and absence of significant coronary obstruction is this hallmark of this condition. However, various morphologic variants with different ventricular region involvement have been reported including "an atypical variant" where the left ventricular hypokinesia is restricted to the midventricular segment without involvement of the apex. Here we present a case of 56-year-old female with a history of chronic anxiety who presented with retrosternal chest pain after her partner threatened to leave her. Her EKG showed diffuse T-wave changes with prolonged QT intervals. She also had modest elevation of cardiac enzymes.
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22
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Dopant-induced ignition of helium nanodroplets in intense few-cycle laser pulses. PHYSICAL REVIEW LETTERS 2011; 107:173402. [PMID: 22107516 DOI: 10.1103/physrevlett.107.173402] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Indexed: 05/31/2023]
Abstract
We demonstrate ultrafast resonant energy absorption of rare-gas doped He nanodroplets from intense few-cycle (~10 fs) laser pulses. We find that less than 10 dopant atoms "ignite" the droplet to generate a nonspherical electronic nanoplasma resulting ultimately in complete ionization and disintegration of all atoms, although the pristine He droplet is transparent for the laser intensities applied. Our calculations at those intensities reveal that the minimal pulse length required for ignition is about 9 fs.
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A Thomson parabola ion imaging spectrometer designed to probe relativistic intensity ionization dynamics of nanoclusters. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2011; 82:083303. [PMID: 21895239 DOI: 10.1063/1.3624698] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Conventional techniques of probing ionization dynamics at relativistic intensities for extended target systems such as clusters are difficult both due to problems of achieving good charge resolution and signal integration over the focal volume. Simultaneous measurement of arrival time, necessary for these systems, has normally involved complicated methods. We designed and developed a Thomson parabola imaging spectrometer that overcomes these problems. Intensity sampling method evolved in this report is proved to be mandatory for probing ionization dynamics of clusters at relativistic intensities. We use this method to measure charge resolved kinetic energy spectra of argon nanoclusters at intensities of 4 × 10(18) W cm(-2).
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Conditional β1-integrin-deficient mice display impaired pancreatic β cell function. J Pathol 2011; 224:45-55. [PMID: 21381031 DOI: 10.1002/path.2849] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Revised: 12/17/2010] [Accepted: 12/21/2010] [Indexed: 12/13/2022]
Abstract
β1-Integrin, a critical regulator of β cell survival and function, has been shown to protect against cell death and promote insulin expression and secretion in rat and human islet cells in vitro. The aim of the present study was to examine whether the knockout of β1-integrin in collagen I-producing cells would have physiological and functional implications in pancreatic endocrine cells in vivo. Using adult mice with a conditional knockout of β1-integrin in collagen I-producing cells, the effects of β1-integrin deficiency on glucose metabolism and pancreatic endocrine cells were examined. Male β1-integrin-deficient mice display impaired glucose tolerance, with a significant reduction in pancreatic insulin content (p < 0.01). Morphometric analysis revealed a significant reduction in β cell mass (p < 0.001) in β1-integrin-deficient mice, along with a significant decrease in β cell proliferation, Pdx-1 and Nkx6.1 expression when compared with controls. Interestingly, these physiological and morphometric alterations in female β1-integrin-deficient mice were less significant. Furthermore, β1-integrin-deficient mice displayed decreased FAK (p < 0.05) and ERK1/2 (p < 0.001) phosphorylation, reduced cyclin D1 levels (p < 0.001) and increased caspase 3 cleavage (p < 0.01), while no changes in Akt phosphorylation were observed, indicating that the β1-integrin signals through the FAK-MAPK-ERK pathway in vivo. Our results demonstrate that β1-integrin is involved in the regulation of glucose metabolism and contributes to the maintenance of β cell survival and function in vivo.
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Abstract
ABSTRACTNucleation and growth mechanisms in the formation of heteroepitaxial films are reviewed. The various processes can be incorporated into rate equations to model the number density and size distribution of clusters.Recent work on extensions of this approach to include the effect of surface steps and other surface imperfections is highlighted.The most important processes are being studied experimentally using a combination of surface-analytic and -microscopic techniques, based on SEM and STEM instrumentation. Recent examples are given in which nucleation densities, surface diffusion lengths and the effects of steps have been studied in the systems Ag/Si(lll) and Ge/Si(100).
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26
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Current Trends in Wireless Technologies in Academic Libraries. DESIDOC JOURNAL OF LIBRARY & INFORMATION TECHNOLOGY 2011. [DOI: 10.14429/djlit.31.1.763] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Effect of forkhead box O1 (FOXO1) on beta cell development in the human fetal pancreas. Diabetologia 2010; 53:699-711. [PMID: 20033803 DOI: 10.1007/s00125-009-1632-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2009] [Accepted: 11/10/2009] [Indexed: 10/20/2022]
Abstract
AIMS/HYPOTHESIS Recent studies have demonstrated that in adult murine beta cells the forkhead box O1 (FOXO1) transcription factor regulates proliferation and stress resistance. However, the role of FOXO1 during pancreatic development remains largely unknown. The present study aimed to characterise the expression of the FOXO1 transcription factor in the early to mid-gestation human fetal pancreas and to understand its role in islet cell development. METHODS Human (8-21 week fetal age) pancreases were examined using immunohistological, quantitative RT-PCR and western blotting. Isolated human (18-21 week) fetal islet epithelial cell clusters were treated with insulin or glucose, or transfected with FOXO1 small interfering RNA (siRNA). RESULTS Nuclear and cytoplasmic FOXO1 were widely produced during human fetal endocrine pancreatic development, co-localising in cells with the transcription factors pancreatic and duodenal homeobox 1 (PDX-1) and neurogenin 3 (NGN3) as well as cytokeratin 19 (CK19), insulin and glucagon. Treatment with exogenous insulin (50 nmol/l) induced the nuclear exclusion of FOXO1 in both cytokeratin 19 (CK19)(+) (p < 0.01) and insulin(+) cells (p < 0.05) in parallel with increased phospho-Akt (p < 0.05) production. siRNA knockdown of FOXO1 significantly increased the number of NGN3(+) (p < 0.01) and NK6 homeobox 1 (NKX6-1)(+) (p < 0.05) cells in parallel with increases in insulin gene expression (p < 0.03) and C-peptide(+) cells (p < 0.05) and reduced levels of hairy and enhancer of split 1 (HES1) (p < 0.01). CONCLUSIONS/INTERPRETATION Our results indicate that FOXO1 may negatively regulate beta cell differentiation in the human fetal pancreas by controlling critical transcription factors, including NGN3 and NKX6-1. These data suggest that the manipulation of FOXO1 levels may be a useful tool for improving cell-based strategies for the treatment of diabetes.
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Direct, absolute, and in situ measurement of fast electron transport via Cherenkov emission. PHYSICAL REVIEW LETTERS 2010; 104:055001. [PMID: 20366770 DOI: 10.1103/physrevlett.104.055001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Indexed: 05/29/2023]
Abstract
We present direct measurements of the absolute energy distribution of relativistic electrons generated in intense, femtosecond laser interaction with a solid. Cherenkov emission radiated by these electrons in a novel prism target is spectrally dispersed to obtain yield and energy distribution of electrons simultaneously. A crucial advance is the observation of high density electron current as predicted by particle simulations and its transport as it happens inside the target. In addition, the strong sheath potential present at the rear side of the target is inferred from a comparison of the electron spectra derived from Cherenkov light observation with that from a magnet spectrometer.
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29
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Study of B meson decays with excited eta and eta' mesons. PHYSICAL REVIEW LETTERS 2008; 101:091801. [PMID: 18851601 DOI: 10.1103/physrevlett.101.091801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Indexed: 05/26/2023]
Abstract
Using 383 x 10(6) BBover pairs from the BABAR data sample, we report results for branching fractions of six charged B-meson decay modes, where a charged kaon recoils against a charmless resonance decaying to KKover* or etapipi final states with mass in the range (1.2-1.8) GeV/c2. We observe a significant enhancement at the low KKover* invariant mass which is interpreted as B+-->eta(1475)K+, find evidence for the decay B+-->eta(1295)K+, and place upper limits on the decays B+-->eta(1405)K+, B+-->f1(1285)K+, B+-->f1(1420)K+, and B+-->phi(1680)K+.
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30
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Observation of Y(3940) --> J/psiomega in B --> J/psiomegaK at BABAR. PHYSICAL REVIEW LETTERS 2008; 101:082001. [PMID: 18764603 DOI: 10.1103/physrevlett.101.082001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2007] [Indexed: 05/26/2023]
Abstract
We present a study of the decays B;{0,+}-->J/psiomegaK;{0,+} using 383x10;{6} BB[over ] events obtained with the BABAR detector at PEP-II. We observe Y(3940)-->J/psiomega, with mass 3914.6_{-3.4};{+3.8}(stat)+/-2.0(syst) MeV/c;{2}, and width 34_{-8};{+12}(stat)+/-5(syst) MeV. The ratio of B0 and B+ decay to YK is 0.27_{-0.23};{+0.28}(stat)-0.01+0.04(syst), and the relevant B0 and B+ branching fractions are reported.
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31
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Transcription factor expression in the developing human fetal endocrine pancreas. Diabetologia 2008; 51:1169-80. [PMID: 18491072 DOI: 10.1007/s00125-008-1006-z] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Accepted: 03/03/2008] [Indexed: 02/06/2023]
Abstract
AIMS/HYPOTHESIS Morphological changes that occur during pancreatic endocrine cell differentiation have been shown in rodent systems to be dependent on sequential alterations in transcription factor expression. However, similar data for humans have been limited. The aim of the present study was to provide a connection between pancreatic morphology, transcription factor gene expression and protein localisation during human fetal development. METHODS Human fetal pancreases were examined at early (8-12 weeks of fetal age), middle (14-16 weeks) and late (19-21 weeks) stages, using immunohistological, microarray and qRT-PCR analyses. RESULTS We observed a significant decrease in pancreatic duodenal homeobox 1 (PDX-1)(+)/cytokeratin 19(+) cells (p < 0.001), with a simultaneous increase in PDX-1(+)/insulin(+) cells from 8 to 21 weeks (p < 0.05). Increased PDX-1/insulin co-localisation within islet clusters was noted, while no co-expression of PDX-1 with glucagon was found, suggesting that loss of PDX-1 is essential for alpha cell formation. Given that neurogenin 3 (NGN3) expression is critical for establishing the endocrine cell programme in the rodent pancreas, we examined its expression pattern and co-localisation in PDX-1(+), insulin(+) and glucagon(+) cells. Co-localisation of NGN3 with PDX-1, insulin and glucagon was noted during early development, with significant decreases in middle and late stages (p < 0.001). Our microarray and co-localisation analyses of transcription factors linked to NGN3 demonstrated that ISL1 transcription factor (ISL1), neurogenic differentiation 1 (NEUROD1), NK2 related transcription factor related, locus 2 (NKX2-2) and paired box gene 6 (PAX6) were upregulated during development and present in all four endocrine cell types, while NK6 related transcription factor related, locus 1 (NKX6-1) was expressed exclusively in beta cells. CONCLUSIONS/INTERPRETATION This study is an important step towards identifying key molecular factors involved in development of the human fetal endocrine pancreas.
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Observation of tree-level B decays with ss production from gluon radiation. PHYSICAL REVIEW LETTERS 2008; 100:171803. [PMID: 18518280 DOI: 10.1103/physrevlett.100.171803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Indexed: 05/26/2023]
Abstract
We report on our search for decays proceeding via a tree-level b-->c quark transition in which a gluon radiates into an ss[over ] pair. We present observations of the decays B;{-}-->D_{s};{+}K;{-}pi;{-} and B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and evidence for B;{-}-->D_{s};{+}K;{-}K;{-} and set upper limits on the branching fractions for B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and B;{-}-->D_{s};{+}K;{-}K;{-} using 383x10;{6} Upsilon(4S)-->BB[over ] events collected by the BABAR detector at SLAC. We present evidence that the invariant mass distributions of D_{s};{+}K;{-} pairs from B;{-}-->D_{s};{+}K;{-}pi;{-} decays are inconsistent with the phase-space model, suggesting the presence of charm resonances lying below the D_{s};{+}K;{-} threshold.
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Measurements of partial branching fractions for B-->Xulnu and determination of |Vub|. PHYSICAL REVIEW LETTERS 2008; 100:171802. [PMID: 18518279 DOI: 10.1103/physrevlett.100.171802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Revised: 03/14/2008] [Indexed: 05/26/2023]
Abstract
We present partial branching fractions for inclusive charmless semileptonic B decays B[over ]-->X_{u}lnu[over ], and the determination of the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}|. The analysis is based on a sample of 383 x 10;{6} Upsilon(4S) decays into BB[over ] pairs collected with the BABAR detector at the SLAC PEP-II e;{+}e;{-} storage rings. We select events using the invariant mass M_{X} of the hadronic system, the invariant mass squared, q;{2}, of the lepton and neutrino pair, the kinematic variable P+, or one of their combinations. We then determine partial branching fractions in limited regions of phase space: DeltaB=(1.18+/-0.09_{stat}+/-0.07_{syst}+/-0.01_{theor})x10;{-3} (M_{X}<1.55 GeV/c;{2}), DeltaB=(0.95+/-0.10_{stat}+/-0.08_{syst}+/-0.01_{theor})x10;{-3} (P+<0.66 GeV/c), and DeltaB=(0.81+/-0.08_{stat}+/-0.07_{syst}+/-0.02_{theor})x10;{-3} (M_{X}<1.7 GeV/c;{2}, q;{2}>8 GeV;{2}/c;{4}). Corresponding values of |V_{ub}| are extracted using several theoretical calculations.
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Observation of B;{0}-->K;(*0)K[over ](*0) and Search for B;(0)-->K;(*0)K;(*0). PHYSICAL REVIEW LETTERS 2008; 100:081801. [PMID: 18352615 DOI: 10.1103/physrevlett.100.081801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Indexed: 05/26/2023]
Abstract
We report the observation of the b-->d penguin-dominated decay B;{0}-->K;{*0}K[over ];{*0} with a sample of 383.2+/-4.2 million BB[over ] pairs collected with the BABAR detector at the PEP-II asymmetric-energy e;{+}e;{-} collider at the Stanford Linear Accelerator Center. The measured branching fraction is B(B;{0}-->K;{*0}K[over ];{*0})=[1.28_{-0.30};{+0.35}+/-0.11]x10;{-6} and the fraction of longitudinal polarization is f_{L}(B;{0}-->K;{*0}K[over ];{*0})=0.80_{-0.12};{+0.10}+/-0.06. The first error quoted is statistical and the second systematic. We also obtain an upper limit at the 90% confidence level on the branching fraction for B(B;{0}-->K;{*0}K;{*0})<0.41x10;{-6}.
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Search for CP violation in the decays D0 --> K- K+ and D0 --> pi- pi+. PHYSICAL REVIEW LETTERS 2008; 100:061803. [PMID: 18352456 DOI: 10.1103/physrevlett.100.061803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Indexed: 05/26/2023]
Abstract
We measure time-integrated CP-violating asymmetries of neutral charmed mesons in the modes D0 --> K(-) K(+) and D0 --> pi(-) pi(+) with the highest precision to date by using D0 --> K(-) pi(+) decays to correct detector asymmetries. An analysis of 385.8 fb(-1) of data collected with the BABAR detector yields values of a(CP)(KK)=(0.00+/-0.34(stat)+/-0.13(syst))% and a(CP)(pipi)=(-0.24+/-0.52(stat)+/-0.22(syst))%, which agree with standard model predictions.
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Measurement of the absolute branching fraction of D0-->K-pi+. PHYSICAL REVIEW LETTERS 2008; 100:051802. [PMID: 18352359 DOI: 10.1103/physrevlett.100.051802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2007] [Indexed: 05/26/2023]
Abstract
We measure the absolute branching fraction for D(0)-->K(-)pi(+) using partial reconstruction of B(0)-->D(*+)Xl(-)nu(l) decays, in which only the charged lepton and the pion from the decay D(*+)-->D(0)pi(+) are used. Based on a data sample of 230 x 10(6) BB pairs collected at the Upsilon(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, we obtain B(D(0)-->K(-)pi(+)) = (4.007+/-0.037+/-0.072)%, where the first uncertainty is statistical and the second is systematic.
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Observation of B+-->a1+(1260)K0 and B0-->a1-(1260)K+. PHYSICAL REVIEW LETTERS 2008; 100:051803. [PMID: 18352360 DOI: 10.1103/physrevlett.100.051803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2007] [Indexed: 05/26/2023]
Abstract
We present branching fraction measurements of the decays B(+)-->a(1)(+)(1260)K(0) and B(0)-->a(1)(-)(1260)K(+) with a(1)(+/-)(1260)-->pi(-/+)pi(+/-)pi(+/-). The data sample corresponds to 383 x 10(6) BB pairs produced in e(+)e(-) annihilation through the Upsilon(4S) resonance. We measure the products of the branching fractions B(B(+)-->a(1)(+)(1260)K(0)B(a(1)(+)(1260)-->pi(-)pi(+)pi(+))=(17.4+/-2.5+/-2.2) x 10(-6) and B(B(0)-->a(1)(-)(1260)K(+)B(a(1)(-)(1260)-->pi(+)pi(-)pi(-)) = (8.2+/-1.5+/-1.2) x 10(-6). We also measure the charge asymmetries A(ch)(B(+)-->a(1)(+)(1260)K(0) = 0.12+/-0.11+/-0.02 and A(ch)(B(0)-->a(1)(-)(1260)K+) = -0.16+/-0.12+/-0.01. The first uncertainty quoted is statistical and the second is systematic.
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Measurement of theCP-violating asymmetries inB0→Ks0π0and of the branching fractionB0→K0π0. Int J Clin Exp Med 2008. [DOI: 10.1103/physrevd.77.012003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Exclusive branching-fraction measurements of semileptonic tau decays into three charged hadrons, into phipi(-)nu tau, and into phi K(-)nu tau. PHYSICAL REVIEW LETTERS 2008; 100:011801. [PMID: 18232752 DOI: 10.1103/physrevlett.100.011801] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Indexed: 05/25/2023]
Abstract
Using a data sample corresponding to an integrated luminosity of 342 fb(-1) collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy near 10.58 GeV, we measure B(tau(-)--> pi(-)pi(-)pi+nu(tau)(ex.K(S0))=(8.83+/-0.01+/-0.13)%, B(tau(-) -->K(-)pi(-)pi+nu tau(ex.K(S0))=(0.273+/-0.002+/-0.009)%, B(tau(-) -->K(-)pi(-)K+nu tau)=(0.1346+/-0.0010+/-0.0036)%, and B(tau(-) -->K(-)K(-)K+nu tau)=(1.58+/-0.13+/-0.12)x10;{-5}, where the uncertainties are statistical and systematic, respectively. These include significant improvements over previous measurements and a first measurement of B(tau(-) -->K(-)K(-)K+nu tau) in which no resonance structure is assumed. We also report a first measurement of B(tau(-) -->var phi(-)nu tau)=(3.42+/-0.55+/-0.25)x10(-5), a new measurement of B(tau(-) -->var phi K(-)nu tau)=(3.39+/-0.20+/-0.28)x10(-5) and a first upper limit on B(tau(-) -->K(-)K(-)K+nu tau(ex.var phi)).
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Evidence for charged B meson decays to a1+/-(1260)pi0 and a1(0)(1260)pi+/-. PHYSICAL REVIEW LETTERS 2007; 99:261801. [PMID: 18233566 DOI: 10.1103/physrevlett.99.261801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2007] [Indexed: 05/25/2023]
Abstract
We present measurements of the branching fractions for the decays B;{+/-}-->a_{1};{+/-}(1260)pi;{0} and B;{+/-}-->a_{1};{0}(1260)pi;{+/-} from a data sample of 232x10;{6} BB[over ] pairs produced in e;{+}e;{-} annihilation through the Upsilon(4S) resonance. We measure the branching fraction B(B;{+/-}-->a_{1};{+/-}(1260)pi;{0})xB(a_{1};{+/-}(1260)-->pi;{-}pi;{+}pi;{+/-})=(13.2+/-2.7+/-2.1)x10;{-6} with a significance of 4.2sigma, and the branching fraction B(B;{+/-}-->a_{1};{0}(1260)pi;{+/-})xB(a_{1};{0}(1260)-->pi;{-}pi;{+}pi;{0})=(20.4+/-4.7+/-3.4)x10;{-6} with a significance of 3.8sigma, where the first error quoted is statistical and the second is systematic.
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Improved limits on the lepton-flavor violating decays tau{-}-->l{-}l{+}l{-}. PHYSICAL REVIEW LETTERS 2007; 99:251803. [PMID: 18233515 DOI: 10.1103/physrevlett.99.251803] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2007] [Indexed: 05/25/2023]
Abstract
A search for the neutrinoless, lepton-flavor violating decay of the tau lepton into three charged leptons has been performed using 376 fb{-1} of data collected at an e{+}e{-} center-of-mass energy around 10.58 GeV with the BABAR detector at the SLAC PEP-II storage rings. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (4-8)x10{-8} at 90% confidence level.
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Measurement of CP violation parameters with a Dalitz plot analysis of B{+/-}-->D{pi{+}pi{-}pi{0}}K{+/-}. PHYSICAL REVIEW LETTERS 2007; 99:251801. [PMID: 18233513 DOI: 10.1103/physrevlett.99.251801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Indexed: 05/25/2023]
Abstract
We report the results of a CP violation analysis of the decay B{+/-}-->D{pi{+}pi{-}pi;{0}}K{+/-}, where D{pi{+}pi{-}pi{0}} indicates a neutral D meson detected in the final state pi{+}pi{-}pi{0}, excluding K{S}{0}pi{0}. The analysis makes use of 324 x 10{6}e{+}e{-}-->BB[over ] events recorded by the BABAR experiment at the PEP-II e;{+}e;{-} storage ring. Analyzing the pi;{+}pi;{-}pi;{0} Dalitz plot distribution and the B{+/-}-->D{pi{+}pi{-}pi{0}}K{+/-} branching fraction and decay rate asymmetry, we find the following one-standard-deviation constraints on the amplitude ratio and on the weak and strong phases: 0.06<r{B}<0.78, -30 degrees <gamma<76 degrees , -27 degrees <delta<78 degrees . We also measure the magnitudes and phases of the components of the D{0}-->pi{+}pi{-}pi{0} decay amplitude.
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Observation of B Meson decays to b1pi and b1K. PHYSICAL REVIEW LETTERS 2007; 99:241803. [PMID: 18233439 DOI: 10.1103/physrevlett.99.241803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2007] [Indexed: 05/25/2023]
Abstract
We present the results of searches for decays of B mesons to final states with a b1 meson and a charged pion or kaon. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 382x10(6) BB[over ] pairs produced in e+e- annihilation. The results for the branching fractions are, in units of 10(-6), B(B+-->b1(0)pi+)=6.7+/-1.7+/-1.0, B(B+-->b1(0)K+)=9.1+/-1.7+/-1.0, B(B0-->b1(-/+)pi(+/-))=10.9+/-1.2+/-0.9, and B(B0-->b1(-)K+)=7.4+/-1.0+/-1.0, with the assumption that B(b1-->omega pi)=1. We also measure charge and flavor asymmetries A(ch)(B+-->b1(0)pi+)=0.05+/-0.16+/-0.02, Ach(B+-->b1(0)K+)=-0.46+/-0.20+/-0.02, A(ch)(B0-->b1(-/+)pi(+/-))=-0.05+/-0.10+/-0.02, C(B0-->b1(-/+)pi(+/-))=-0.22+/-0.23+/-0.05, DeltaC(B0-->b1(-/+)pi(+/-))=-1.04+/-0.23+/-0.08, and A(ch)(B0-->b1(-)K+)=-0.07+/-0.12+/-0.02. The first error quoted is statistical, and the second systematic.
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Measurement of cos2beta in B;{0}-->D;{(*)}h;{0} decays with a time-dependent Dalitz plot analysis of D-->K_{s};{0}pi;{+}pi;{-}. PHYSICAL REVIEW LETTERS 2007; 99:231802. [PMID: 18233357 DOI: 10.1103/physrevlett.99.231802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2007] [Indexed: 05/25/2023]
Abstract
We study the time-dependent Dalitz plot of D-->K_{S};{0}pi;{+}pi;{-} in B;{0}-->D;{(*)}h;{0} decays, where h;{0} is a pi;{0}, eta, eta;{'}, or omega meson and D;{*}-->Dpi;{0}, using a data sample of 383x10;{6} Upsilon(4S)-->BB[over ] decays collected with the BABAR detector. We determine cos2beta=0.42+/-0.49+/-0.09+/-0.13, sin2beta=0.29+/-0.34+/-0.03+/-0.05, and |lambda|=1.01+/-0.08+/-0.02, where the first error is statistical, the second is the experimental systematic uncertainty, and the third, where given, is the Dalitz model uncertainty. Assuming the world average value for sin2beta and |lambda|=1, cos2beta>0 is preferred over cos2beta<0 at 86% confidence level.
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Abstract
We report the observation of charmless hadronic decays of charged B mesons to the final state K{+}K{-}pi{+}. Using a data sample of 347.5 fb{-1} collected at the Upsilon(4S) resonance with the BABAR detector, we observe 429+/-43 signal events with a significance of 9.6sigma. We measure the inclusive branching fraction B(B{+}-->K{+}K{-}pi{+})=[5.0+/-0.5(stat)+/-0.5(syst)]x10{-6}. Inspection of the Dalitz plot of signal candidates shows a broad structure peaking near 1.5 GeV/c{2} in the K+K- invariant mass distribution. We find the direct CP asymmetry to be consistent with zero.
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Amplitude analysis of the B+/--->phiK*(892)+/- decay. PHYSICAL REVIEW LETTERS 2007; 99:201802. [PMID: 18233133 DOI: 10.1103/physrevlett.99.201802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2007] [Indexed: 05/25/2023]
Abstract
We perform an amplitude analysis of B+/--->phi(1020)K*(892)+/- decay with a sample of about 384 x 10(6) BB[over ] pairs recorded with the BABAR detector. Overall, twelve parameters are measured, including the fractions of longitudinal fL and parity-odd transverse f perpendicular amplitudes, branching fraction, strong phases, and six parameters sensitive to CP violation. We use the dependence on the Kpi invariant mass of the interference between the JP=1(-) and 0+ Kpi components to resolve the discrete ambiguity in the determination of the strong and weak phases. Our measurements of fL=0.49+/-0.05+/-0.03, f perpendicular=0.21+/-0.05+/-0.02, and the strong phases point to the presence of a substantial helicity-plus amplitude from a presently unknown source.
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Search for the Decay B+-->K+ tau-/+ mu+/-. PHYSICAL REVIEW LETTERS 2007; 99:201801. [PMID: 18233132 DOI: 10.1103/physrevlett.99.201801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2007] [Indexed: 05/25/2023]
Abstract
We present a search for the lepton flavor violating decay B+-->K+ tau-/+ mu+/- using 383 x 10;{6} BB[over ] events collected by the BABAR experiment. The branching fraction for this decay can be substantially enhanced in new physics models. The kinematics of the tau from the signal B decay are inferred from the K+, mu, and other B in the event, which is fully reconstructed in one of a variety of hadronic decay modes, allowing the signal B candidate to be fully reconstructed. We observe no excess of events over the expected background and set a limit of B(B+-->K+ tau mu)<7.7 x 10(-5) at 90% confidence level, where the branching fraction is for the sum of the K+ tau- mu+ and K+ tau+mu- final states. We use this result to improve a model-independent bound on the energy scale of flavor-changing new physics.
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Improved measurement of CP violation in neutral B decays to cc[over]s. PHYSICAL REVIEW LETTERS 2007; 99:171803. [PMID: 17995319 DOI: 10.1103/physrevlett.99.171803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Indexed: 05/25/2023]
Abstract
We present updated measurements of time-dependent CP asymmetries in fully-reconstructed neutral B decays to several CP eigenstates containing a charmonium meson. The measurements use a data sample of (383+/-4)x10(6) Upsilon(4S)-->BB[over] decays collected with the BABAR detector at the PEP-II B factory. We determine sin2beta = 0.714+/-0.032(stat)+/-0.018(syst) and |lambda|=0.952+/-0.022(stat)+/-0.017(syst).
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