9,649 research outputs found

    The nature of ZbZ_b states from a combined analysis of Υ(5S)hb(mP)π+π\Upsilon(5S)\rightarrow h_b(mP) \pi^+ \pi^- and Υ(5S)B()Bˉ()π\Upsilon(5S)\rightarrow B^{(\ast)}\bar B^{(\ast)}\pi

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    With a combined analysis of data on Υ(5S)hb(1P,2P)π+π\Upsilon(5S)\rightarrow h_b(1P,2P)\pi^+\pi^- and Υ(5S)B()Bˉ()π\Upsilon(5S)\rightarrow B^{(\ast)}\bar B^{(\ast)}\pi in an effective field theory approach, we determine resonance parameters of ZbZ_b states in two scenarios. In one scenario we assume that ZbZ_b states are pure molecular states, while in the other one we assume that ZbZ_b states contain compact components. We find that the present data favor that there should be some compact components inside Zb()Z_b^{(\prime)} associated with the molecular components. By fitting the invariant mass spectra of Υ(5S)hb(1P,2P)π+π\Upsilon(5S)\rightarrow h_b(1P,2P)\pi^+\pi^- and Υ(5S)B()Bˉπ\Upsilon(5S)\rightarrow B^{(\ast)}\bar B^{\ast}\pi, we determine that the probability of finding the compact components in ZbZ_b states may be as large as about 40%40\%.Comment: Discussions added, version published in EPJ

    On the Relationship between Pubovisceral Muscle Tears and Urethral Closure Pressure in Women Following Vaginal Birth

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    Little is known about the implications of pubovisceral muscle tear on urethral closure pressure – the focus of this dissertation. The literature on interventions for stress urinary incontinence has focused almost exclusively on pubovisceral muscle strengthening with repetitive exercise for life, but to date reports on “strength change” and on “leakage reduction” fail to convincingly relate these two outcomes, and essentially none of the studies reported take into account pubovisceral muscle tear, which renders the muscle incapable of response to volitional contraction effort. These major limitations in the literature are largely due to a long struggle to find adequate valid, cost effective, acceptable, accessible, reliable measures for the constructs of pubovisceral muscle. Recent major advances have been made in the field of pubovisceral muscle measurement, but come with a history (70+ years) of measurement difficulties that have caused fixed ideas and misunderstandings. This dissertation advances our understanding of measures of pubovisceral muscle structure (tears at the enthesis) and pubovisceral muscle function (loss of capacity for strength), suggests gold standard measures, advances the possibility of cost-effective clinical screening exams, and then for the first time examines in a sample of postpartum women known to have had obstetric high-risk factors at delivery the relationship of pubovisceral muscle tear to urethral closure pressure. The dissertation has three purposes: 1) reviewing past and current measures for assessing pubovisceral muscle strength and pubovisceral muscle tear; 2) estimating the odds of pubovisceral muscle tear (with gold standard magnetic resonance imaging) from clinical examination identifying using index finger palpatory assessment; and 3) determining predictive value of pubovisceral muscle tear on urethral closure pressure both at rest and during volitional effort of pelvic muscle contraction. The findings from the research suggest that there are gold standard measures (MRI and one-billed speculum) that are unsurpassed in meeting criteria of precise, valid, acceptable to women, but with some not broadly accessible in part due to prohibitive cost factors and lack of technology transfer from the research arena to the public. Quantified standing stress paper towel test and sagittal dynamic ultrasound for estimating pubovisceral muscle function in women with stress incontinence are suggested for adoption widely in the clinical setting, where currently implementation is nearly non-existent. The findings also suggest, for either scientific or clinical purposes, to avoid commonly used intravaginal instrument devices known to produce measures contaminated by intraabdominal pressure, making it impossible to isolate the pubovisceral muscle activities from non-pubovisceral muscle activity occurring simultaneously. The findings further suggest that index finger palpatory assessment can be used to initially identify pubovisceral muscle tear. Finally, the findings demonstrate the strong influence of the pubovisceral muscle tear (unstandardized coefficient = - 21.1; p=.001) on reducing a woman’s ability to volitionally optimize urethral closure pressure at the moment of intraabdominal pressure rise (as in cough), to prevent stress-type incontinence. These findings establish the foundation for future prospective research on estimation of pubovisceral muscle status in parous women who have vaginal birth and have risk factors for pubovisceral muscle tear, as well as identifying the role of volitional urethral closure pressure for future prevention and intervention studies on stress incontinence. This dissertation provides crucial data to inform the field focusing on testing pubovisceral muscle tear and the tear’ influences on the urethra, as well as the prevention and intervention for stress urinary incontinence.PHDNursingUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/143908/1/shying_1.pd
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