796 research outputs found

    Orientational phase transitions in the hexagonal phase of a diblock copolymer melt under shear flow

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    We generalize the earlier theory by Fredrickson [J. Rheol. v.38, 1045 (1994)] to study the orientational behaviour of the hexagonal phase of diblock copolymer melt subjected to steady shear flow. We use symmetry arguments to show that the orientational ordering in the hexagonal phase is a much weaker effect than in the lamellae. We predict the parallel orientation to be stable at low and the perpendicular orientation at high shear rates. Our analysis reproduces the experimental results by Tepe et al. [Macromolecules v.28, 3008 (1995)] and explains the difficulties in experimental observation of the different orientations in the hexagonal phase.Comment: 21 pages, 6 eps figures, submitted to Physical Review

    Paclitaxel-Coated Balloon for the Treatment of Infrainguinal Disease: 12-Month Outcomes in the All-Comers Cohort of BIOLUX P-III Global Registry

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    Purpose: To further investigate the safety and performance of the Passeo-18 Lux drug-coated balloon (DCB) for the treatment of atherosclerotic infrainguinal disease under real-world conditions. Materials and Methods: BIOLUX P-III is an international, prospective, observational registry (ClinicalTrials.gov identifier NCT02276313) conducted at 41 centers in Europe, Asia, and Australia with follow-up visits at 6, 12, and 24 months. Of 700 patients (mean age 70.0\ub110.2 years; 439 men) with 863 lesions in the all-comers cohort, 330 (47.1%) patients had diabetes and 234 (37.7%) had chronic limb-threatening ischemia. The majority (79.3%) of lesions were in the femoropopliteal segment; of all lesions, 645 (74.9%) were calcified and 99 (11.5%) had in-stent restenosis (ISR). The mean lesion length was 84.7\ub173.3 mm. The primary clinical endpoint was major adverse events (MAEs) within 6 months, a composite of device- and procedure-related mortality through 30 days, major target limb amputation, and clinically-driven target lesion revascularization (TLR). The primary performance endpoint was clinically-driven TLR within 12 months. Results: At 6 and 12 months, freedom from MAEs was 94.0% and 89.5% in the all-comers cohort: 95.0% and 91.2% in the femoropopliteal group and 95.3% and 88.0% in the ISR subgroup, respectively. Freedom from clinically-driven TLR at 12 months was 93.1% in the all-comers cohort, 93.9% in the femoropopliteal lesions, and 89.4% for ISR lesions. All-cause mortality was 6.1% in the all-comers cohort: 5.9% in both the femoropopliteal and ISR subgroups. There were no device- or procedure-related deaths at up to 12 months. The Rutherford category improved in >80% of all subgroups at 12 months. Conclusion: In a real-world patient population, the safety and performance of the Passeo-18 Lux DCB for the treatment of atherosclerotic infrainguinal lesions are maintained, with good performance outcomes and low complication rates at 12 months

    Multiple recent horizontal transfers of the cox1 intron in Solanaceae and extended co-conversion of flanking exons

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    Background: The most frequent case of horizontal transfer in plants involves a group I intron in the mitochondrial gene cox1, which has been acquired via some 80 separate plant-to-plant transfer events among 833 diverse angiosperms examined. This homing intron encodes an endonuclease thought to promote the intron´s promiscuous behavior. A promising experimental approach to study endonuclease activity and intron transmission involves somatic cell hybridization, which in plants leads to mitochondrial fusion and genome recombination. However, the cox1 intron has not yet been found in the ideal group for plant somatic genetics - the Solanaceae. We therefore undertook an extensive survey of this family to find members with the intron and to learn more about the evolutionary history of this exceptionally mobile genetic element. Results: Although 409 of the 426 species of Solanaceae examined lack the cox1 intron, it is uniformly present in three phylogenetically disjunct clades. Despite strong overall incongruence of cox1 intron phylogeny with angiosperm phylogeny, two of these clades possess nearly identical intron sequences and are monophyletic in intron phylogeny. These two clades, and possibly the third also, contain a co-conversion tract (CCT) downstream of the intron that is extended relative to all previously recognized CCTs in angiosperm cox1. Re-examination of all published cox1 genes uncovered additional cases of extended co-conversion and identified a rare case of putative intron loss, accompanied by full retention of the CCT. Conclusions: We infer that the cox1 intron was separately and recently acquired by at least three different lineages of Solanaceae. The striking identity of the intron and CCT from two of these lineages suggests that one of these three intron captures may have occurred by a within-family transfer event. This is consistent with previous evidence that horizontal transfer in plants is biased towards phylogenetically local events. The discovery of extended co-conversion suggests that other cox1 conversions may be longer than realized but obscured by the exceptional conservation of plant mitochondrial sequences. Our findings provide further support for the rampant-transfer model of cox1 intron evolution and recommend the Solanaceae as a model system for the experimental analysis of cox1 intron transfer in plants.Fil: Sánchez Puerta, María Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Abbona, Cinthia Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Zhuo, Shi. Indiana University; Estados UnidosFil: Tepe, Eric J.. University of Cincinnati; Estados Unidos. University of Utah; Estados UnidosFil: Bohs, Lynn. University of Utah; Estados UnidosFil: Olmstead, Richard G.. University of Washington; Estados UnidosFil: Palmer, Jeffrey D.. Indiana University; Estados Unido

    Influence of confinement on the orientational phase transitions in the lamellar phase of a block copolymer melt under shear flow

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    In this work we incorporate some real-system effects into the theory of orientational phase transitions under shear flow (M. E. Cates and S. T. Milner, Phys. Rev. Lett. v.62, p.1856 (1989) and G. H. Fredrickson, J. Rheol. v.38, p.1045 (1994)). In particular, we study the influence of the shear-cell boundaries on the orientation of the lamellar phase. We predict that at low shear rates the parallel orientation appears to be stable. We show that there is a critical value of the shear rate at which the parallel orientation loses its stability and the perpendicular one appears immediately below the spinodal. We associate this transition with a crossover from the fluctuation to the mean-field behaviour. At lower temperatures the stability of the parallel orientation is restored. We find that the region of stability of the perpendicular orientation rapidly decreases as shear rate increases. This behaviour might be misinterpreted as an additional perpendicular to parallel transition recently discussed in literature.Comment: 25 pages, 4 figures, submitted to Phys. Rev.

    Real-world experience with a Paclitaxel-Coated Balloon for the treatment of atherosclerotic infrainguinal arteries: 12-month interim results of the BIOLUX P-III registry first year of enrolment = Experiência real com balão revestido com paclitaxel para o tratamento de artérias infrainguinais ateroscleróticas: resultados após 12 meses do primeiro ano de seleção de pacientes para o registro BIOLUX P-III

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    Background: Endovascular management of atherosclerotic infrainguinal arteries recently shifted towards drug eluting devices, designed to locally prevent the restenosis process. Numerous clinical studies report an advantage of drug coated balloons over uncoated balloon angioplasty in treating lower extremity peripheral artery disease. However, as coating and balloon platforms are different, each device requires dedicated clinical evaluations. Objective: The aim of the study is to further investigate the safety and effectiveness of a Paclitaxel-Coated Balloon for the treatment of atherosclerotic infrainguinal arteries in a real-world setting. Methods: 203 patients out of a final sample of 882 were enrolled in this prospective multicenter, observational, all-comers registry during the first 12 months. The primary endpoints were major adverse events (defined as procedure or device related death within 30 days post index procedure, clinically-driven target lesion revascularization or major target limb amputation) at 6 months and freedom from clinically-driven target lesion revascularization at 12 months. Both endpoints were adjudicated by a Clinical Events Committee. Results: Mean patient age was 70.2\ub110.4 years (60.1% male). 47.3% of the patients were diabetic and 67.5% had a history of smoking. Severe claudication was reported in 37.4% and 40% had critical limb ischemia. 257 lesions, including 13.2% in the infrapopliteal territory, were treated with Passeo-18 Lux (mean lesion length 75.1 mm\ub169.4, 20% occlusions, 76.3% calcified). At 6 months, the rate of major adverse events was 5.5% (95%CI 3.1-9.7). Freedom from clinically-driven target lesion revascularization at 12 months was 93.2% (95%CI 89.1-95.8). All causes mortality was 6.5% (95%CI 3.8-11.0) and overall amputation rate was 4.2% (95%CI 2.1-8.3) at 12 months. Conclusion: In a real-world environment, the BIOLUX P-III registry preliminary results confirm the safety and efficacy of the Paclitaxel-Coated Passeo-18 Lux balloon as a stand-alone treatment option for atherosclerotic infrainguinal arteries.Contexto: O manejo endovascular de art\ue9rias infrainguinais ateroscler\uf3ticas recentemente tem mudado para dispositivos farmacol\uf3gicos, desenhados para impedir localmente o processo de reestenose. Numerosos estudos cl\uednicos descrevem uma vantagem da angioplastia com uso de bal\uf5es farmacol\uf3gicos sobre os bal\uf5es convencionais no tratamento de doen\ue7a arterial perif\ue9rica dos membros inferiores. No entanto, considerando que as plataformas do revestimento farmacol\uf3gico e dos bal\uf5es s\ue3o diferentes, cada dispositivo requer avalia\ue7\uf5es cl\uednicas espec\uedficas. Objetivo: Fazer investiga\ue7\ue3o adicional sobre a seguran\ue7a e efic\ue1cia de um bal\ue3o revestido com paclitaxel para o tratamento de art\ue9rias infrainguinais ateroscler\uf3ticas em um cen\ue1rio de mundo real. M\ue9todos: 203 pacientes de uma amostra final de 882 pacientes foram inclu\ueddos neste registro prospectivo observacional multic\ueantrico de inclus\ue3o sequencial, durante os primeiros 12 meses. Os desfechos prim\ue1rios foram eventos adversos maiores (definidos como morte relacionada ao procedimento ou ao dispositivo em at\ue9 30 dias ap\uf3s o procedimento-\uedndice, necessidade de revasculariza\ue7\ue3o da les\ue3o-alvo ou amputa\ue7\ue3o significativa do membro-alvo) em 6 meses e aus\ueancia de de revasculariza\ue7\ue3o da les\ue3o-alvo em 12 meses. Ambos os desfechos foram adjudicados por um comit\uea de eventos cl\uednicos. Resultados: A idade m\ue9dia foi 70,2\ub110,4 anos (60,1% sexo masculino). 47,3% dos pacientes eram diab\ue9ticos, e 67,5% tinham hist\uf3ria de tabagismo. Claudica\ue7\ue3o severa foi relatada em 37,4%, e 40% apresentava isquemia cr\uedtica de membro. 257 les\uf5es, incluindo 13,2% em territ\uf3rio infrapopl\uedteo, foram tratadas com o bal\ue3o Passeo-18 Lux (comprimento m\ue9dio das les\uf5es 75,1 mm\ub169,4, 20% oclus\uf5es, 76,3% calcificadas). Aos 6 meses, a taxa de eventos adversos maiores foi de 5,5% (95%CI 3,1-9,7). A aus\ueancia de revasculariza\ue7\ue3o da les\ue3o-alvo aos 12 meses foi de 93,2% (95%CI 89,1-95,8). Mortalidade por todas as causas foi de 6,5% (95%CI 3,8-11,0) e a taxa geral de amputa\ue7\ue3o foi de 4,2% (95%CI 2,1-8,3) aos 12 meses. Conclus\ue3o: Em um cen\ue1rio de mundo real, os resultados preliminares do registro BIOLUX P-III confirmam a seguran\ue7a e efic\ue1cia do bal\ue3o revestido com paclitaxel Passeo-18 Lux como op\ue7\ue3o de tratamento \ufanico para art\ue9rias infrainguinais ateroscler\uf3ticas

    Turner syndrome and associated problems in turkish children: A multicenter study

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    Objective: Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population. Methods: Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014. Results: The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosi) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto’s thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%. Conclusion: This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespan. © Journal of Clinical Research in Pediatric Endocrinology

    VAMOS: a Pathfinder for the HAWC Gamma-Ray Observatory

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    VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-shower array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight months of data were used to obtain the results presented in this paper: the detector response to the Forbush decrease of March 2012, and the analysis of possible emission, at energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.Comment: Accepted for pubblication in Astroparticle Physics Journal (20 pages, 10 figures). Corresponding authors: A.Marinelli and D.Zaboro

    Search for non-relativistic Magnetic Monopoles with IceCube

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    The IceCube Neutrino Observatory is a large Cherenkov detector instrumenting 1km31\,\mathrm{km}^3 of Antarctic ice. The detector can be used to search for signatures of particle physics beyond the Standard Model. Here, we describe the search for non-relativistic, magnetic monopoles as remnants of the GUT (Grand Unified Theory) era shortly after the Big Bang. These monopoles may catalyze the decay of nucleons via the Rubakov-Callan effect with a cross section suggested to be in the range of 1027cm210^{-27}\,\mathrm{cm^2} to 1021cm210^{-21}\,\mathrm{cm^2}. In IceCube, the Cherenkov light from nucleon decays along the monopole trajectory would produce a characteristic hit pattern. This paper presents the results of an analysis of first data taken from May 2011 until May 2012 with a dedicated slow-particle trigger for DeepCore, a subdetector of IceCube. A second analysis provides better sensitivity for the brightest non-relativistic monopoles using data taken from May 2009 until May 2010. In both analyses no monopole signal was observed. For catalysis cross sections of 1022(1024)cm210^{-22}\,(10^{-24})\,\mathrm{cm^2} the flux of non-relativistic GUT monopoles is constrained up to a level of Φ901018(1017)cm2s1sr1\Phi_{90} \le 10^{-18}\,(10^{-17})\,\mathrm{cm^{-2}s^{-1}sr^{-1}} at a 90% confidence level, which is three orders of magnitude below the Parker bound. The limits assume a dominant decay of the proton into a positron and a neutral pion. These results improve the current best experimental limits by one to two orders of magnitude, for a wide range of assumed speeds and catalysis cross sections.Comment: 20 pages, 20 figure

    Calibration and Characterization of the IceCube Photomultiplier Tube

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    Over 5,000 PMTs are being deployed at the South Pole to compose the IceCube neutrino observatory. Many are placed deep in the ice to detect Cherenkov light emitted by the products of high-energy neutrino interactions, and others are frozen into tanks on the surface to detect particles from atmospheric cosmic ray showers. IceCube is using the 10-inch diameter R7081-02 made by Hamamatsu Photonics. This paper describes the laboratory characterization and calibration of these PMTs before deployment. PMTs were illuminated with pulses ranging from single photons to saturation level. Parameterizations are given for the single photoelectron charge spectrum and the saturation behavior. Time resolution, late pulses and afterpulses are characterized. Because the PMTs are relatively large, the cathode sensitivity uniformity was measured. The absolute photon detection efficiency was calibrated using Rayleigh-scattered photons from a nitrogen laser. Measured characteristics are discussed in the context of their relevance to IceCube event reconstruction and simulation efforts.Comment: 40 pages, 12 figure

    Determining neutrino oscillation parameters from atmospheric muon neutrino disappearance with three years of IceCube DeepCore data

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    We present a measurement of neutrino oscillations via atmospheric muon neutrino disappearance with three years of data of the completed IceCube neutrino detector. DeepCore, a region of denser instrumentation, enables the detection and reconstruction of atmospheric muon neutrinos between 10 GeV and 100 GeV, where a strong disappearance signal is expected. The detector volume surrounding DeepCore is used as a veto region to suppress the atmospheric muon background. Neutrino events are selected where the detected Cherenkov photons of the secondary particles minimally scatter, and the neutrino energy and arrival direction are reconstructed. Both variables are used to obtain the neutrino oscillation parameters from the data, with the best fit given by Δm322=2.720.20+0.19×103eV2\Delta m^2_{32}=2.72^{+0.19}_{-0.20}\times 10^{-3}\,\mathrm{eV}^2 and sin2θ23=0.530.12+0.09\sin^2\theta_{23} = 0.53^{+0.09}_{-0.12} (normal mass hierarchy assumed). The results are compatible and comparable in precision to those of dedicated oscillation experiments.Comment: 10 pages, 7 figure
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