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Objectives: To evaluate possible predictors of elevated postvoid residual volume (PVR) following onabotulinumtoxinA administration in patients with idiopathic overactive bladder (OAB), a condition that may include urinary urgency, frequency, and nocturia, without any identifiable cause or underlying neurological or metabolic condition., Methods: Adults who had been treated with 100-200 U onabotulinumtoxinA for OAB and had previous failure of other OAB treatments were identified by retrospective review of medical chart data from three urology clinics in the United States treating patients with a variety of urological conditions. A total of 211 patients were allocated to cohorts based on posttreatment PVR < 200 mL (n = 173) and ≥ 200 mL (n = 38). Logistic regression analyses were performed to evaluate potential predictors of posttreatment PVR ≥ 200 mL, including pretreatment peak urine flow rate (Qmax), average urine flow rate (Qavg), and Modified Liverpool Qmax and Qavg flow index (FI), and to determine whether patient age and baseline PVR were associated with the likelihood of PVR ≥ 200 mL. Patients were excluded if symptoms of OAB were secondary to a neurological condition, they had a PVR > 200 mL within 2 weeks prior to the index therapy or had been treated with other botulinum toxin formulations for a urinary condition., Results: In the predictor analyses, neither Qmax nor Qavg alone was a likely predictor. Odds ratios of PVR ≥ 200 mL for Modified Liverpool Qmax FI and Qavg were 0.30 (95% CI: 0.08-0.91; p = 0.0488) and 0.07 (95% CI 0.01-0.40; p = 0.0045), respectively. When patient age and baseline PVR were incorporated into the analyses, results suggested that Qmax, Qavg, Qmax FI, and Qavg FI, as well as increased age and baseline PVR, were likely predictors of elevated posttreatment PVR., Conclusions: Patients who are older, have high pretreatment PVR values, and have lower pretreatment urine flow indexes and flows may be at increased risk of developing elevated PVR after receiving onabotulinumtoxinA treatment for OAB., (© 2025 The Author(s). LUTS: Lower Urinary Tract Symptoms published by John Wiley & Sons Australia, Ltd.)

The spin-exotic hybrid meson π&#95;{1}(1600) is predicted to have a large decay rate to the ωππ final state. Using 76.6  pb^{-1} of data collected with the GlueX detector, we measure the cross sections for the reactions γp→ωπ^{+}π^{-}p, γp→ωπ^{0}π^{0}p, and γp→ωπ^{-}π^{0}Δ^{++} in the range E&#95;{γ}=8-10  GeV. Using isospin conservation, we set the first upper limits on the photoproduction cross sections of the π&#95;{1}^{0}(1600) and π&#95;{1}^{-}(1600). We combine these limits with lattice calculations of decay widths and find that photoproduction of η^{'}π is the most sensitive two-body system to search for the π&#95;{1}(1600).

Measuring deeply virtual Compton scattering (DVCS) on the neutron is one of the necessary steps to understand the structure of the nucleon in terms of generalized parton distributions (GPDs). Neutron targets play a complementary role to transversely polarized proton targets in the determination of the GPD E. This poorly known and poorly constrained GPD is essential to obtain the contribution of the quarks' angular momentum to the spin of the nucleon. DVCS on the neutron was measured for the first time selecting the exclusive final state by detecting the neutron, using the Jefferson Lab longitudinally polarized electron beam, with energies up to 10.6 GeV, and the CLAS12 detector. The extracted beam-spin asymmetries, combined with DVCS observables measured on the proton, allow a clean quark-flavor separation of the imaginary parts of the Compton form factors H and E.

Metabolism drives various biological processes, potentially influencing the ecological success and evolutionary fitness of species. Understanding diverse metabolic rates is fundamental in biology. Mechanisms underlying adaptation to factors like temperature and predation pressure remain unclear. Our study explored the role of temperature and predation pressure in shaping the metabolic scaling of an invasive mussel species ( Brachidontes pharaonis ). Specifically, we performed laboratory-based experiments to assess the effects of phenotypic plasticity on the metabolic scaling by exposing the mussels to water conditions with and without predator cues from another invasive species (the blue crab, Callinectes sapidus ) across various temperature regimes. We found that temperature effects on metabolic scaling of the invasive mussels are mediated by the presence of chemical cues of an invasive predator, the blue crab. Investigating temperature-predator interactions underscores the importance of studying the ecological effects of global warming. Our research advances our understanding of how environmental factors jointly impact physiological processes.

We report the measurement of the helicity asymmetry E for the pπ^{0} and nπ^{+} final states using, for the first time, an elliptically polarized photon beam in combination with a longitudinally polarized target at the Crystal Ball experiment at MAMI. The results agree very well with data that were taken with a circularly polarized photon beam, showing that it is possible to simultaneously measure polarization observables that require linearly (e.g., G) and circularly polarized photons (e.g., E) and a longitudinally polarized target. The new data cover a photon energy range 270-1400 MeV for the pπ^{0} final state (230-842 MeV for the nπ^{+} final state) and the full range of pion polar angles, θ, providing the most precise measurement of the observable E. A moment analysis gives a clear observation of the pη cusp in the pπ^{0} final state.

The polarized cross-section ratio σ&#95;{LT^{'}}/σ&#95;{0} from hard exclusive π^{-}Δ^{++} electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2  GeV/10.6  GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5  GeV^{2} up to 7  GeV^{2}. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ^{++} transition generalized parton distributions. A comparison to existing results for hard exclusive π^{+}n and π^{0}p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.

Deeply virtual Compton scattering (DVCS) allows one to probe generalized parton distributions describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6 GeV electron beam scattering from unpolarized protons. The results greatly extend the Q^{2} and Bjorken-x phase space beyond the existing data in the valence region and provide 1600 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.

We report results of Λ hyperon production in semi-inclusive deep-inelastic scattering off deuterium, carbon, iron, and lead targets obtained with the CLAS detector and the Continuous Electron Beam Accelerator Facility 5.014 GeV electron beam. These results represent the first measurements of the Λ multiplicity ratio and transverse momentum broadening as a function of the energy fraction (z) in the current and target fragmentation regions. The multiplicity ratio exhibits a strong suppression at high z and an enhancement at low z. The measured transverse momentum broadening is an order of magnitude greater than that seen for light mesons. This indicates that the propagating entity interacts very strongly with the nuclear medium, which suggests that propagation of diquark configurations in the nuclear medium takes place at least part of the time, even at high z. The trends of these results are qualitatively described by the Giessen Boltzmann-Uehling-Uhlenbeck transport model, particularly for the multiplicity ratios. These observations will potentially open a new era of studies of the structure of the nucleon as well as of strange baryons.

We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction in the deep inelastic scattering process. In this reaction, two hadrons are produced in opposite hemispheres along the z axis in the virtual photon-target nucleon center-of-mass frame, with the first hadron produced in the current-fragmentation region and the second in the target-fragmentation region. The data were taken with longitudinally polarized electron beams of 10.2 and 10.6 GeV incident on an unpolarized liquid-hydrogen target using the CLAS12 spectrometer at Jefferson Lab. Observed nonzero sinΔϕ modulations in ep→e^{'}pπ^{+}X events, where Δϕ is the difference of the azimuthal angles of the proton and pion in the virtual photon and target nucleon center-of-mass frame, indicate that correlations between the spin and transverse momenta of hadrons produced in the target- and current-fragmentation regions may be significant. The measured beam-spin asymmetries provide a first access in dihadron production to a previously unexplored leading-twist spin- and transverse-momentum-dependent fracture function. The fracture functions describe the hadronization of the target remnant after the hard scattering of a virtual photon off a quark in the target particle and provide a new avenue for studying nucleonic structure and hadronization.

A precise measurement of the differential cross sections dσ/dΩ and the linearly polarized photon beam asymmetry Σ&#95;{3} for Compton scattering on the proton below pion threshold has been performed with a tagged photon beam and almost 4π detector at the Mainz Microtron. The incident photons were produced by the recently upgraded Glasgow-Mainz photon tagging facility and impinged on a cryogenic liquid hydrogen target, with the scattered photons detected in the Crystal Ball/TAPS setup. Using the highest statistics Compton scattering data ever measured on the proton along with two effective field theories (both covariant baryon and heavy-baryon) and one fixed-t dispersion relation model, constraining the fits with the Baldin sum rule, we have obtained the proton electric and magnetic polarizabilities with unprecedented precision: α&#95;{E1}=10.99±0.16±0.47±0.17±0.34, β&#95;{M1}=3.14±0.21±0.24±0.20±0.35; in units of 10^{-4}  fm^{3} where the errors are statistical, systematic, spin polarizability dependent, and model dependent.

High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single π^{+} SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q^{2} ranging from 1-7  GeV^{2}. In particular, the structure function ratio F&#95;{LU}^{sinϕ}/F&#95;{UU} has been determined, where F&#95;{LU}^{sinϕ} is a twist-3 quantity that can reveal novel aspects of emergent hadron mass and quark-gluon correlations within the nucleon. The data's impact on the evolving understanding of the underlying reaction mechanisms and their kinematic variation is explored using theoretical models for the different contributing transverse momentum dependent parton distribution functions.

Strange matter is believed to exist in the cores of neutron stars based on simple kinematics. If this is true, then hyperon-nucleon interactions will play a significant part in the neutron star equation of state. Yet, compared to other elastic scattering processes, there is very little data on Λ-N scattering. This experiment utilized the CEBAF Large Acceptance Spectrometer (CLAS) detector to study the Λp→Λp elastic scattering cross section in the incident Λ momentum range 0.9-2.0  GeV/c. These are the first data on this reaction since the 1970s. The new cross sections have significantly better accuracy and precision than the existing world data, and the techniques developed here can also be used in future experiments.

We present the first measurement of the timelike Compton scattering process, γp→p^{'}γ^{*}(γ^{*}→e^{+}e^{-}), obtained with the CLAS12 detector at Jefferson Lab. The photon beam polarization and the decay lepton angular asymmetries are reported in the range of timelike photon virtualities 2.25

Objectives: This randomized, multicenter, placebo-controlled, phase IV study assessed the efficacy and tolerability of onabotulinumtoxinA in patients with overactive bladder., Methods: Patients were randomized 1:1 to onabotulinumtoxinA 100 U or placebo. Assessments over 12 weeks included: change from baseline in urinary incontinence (UI) episodes/day; proportions of patients who achieved 100% and 50% or greater reductions in UI episodes/day; proportion of patients using no incontinence pads in the previous 24 hours; and changes from baseline in micturition frequency, nocturia, urgency UI, Incontinence-Quality of Life, King's Health Questionnaire, International Consultation on Incontinence Questionnaire-UI Short Form scores and time to request retreatment., Results: Significant reductions in UI episodes/day were seen with onabotulinumtoxinA versus placebo within week 1 posttreatment (-2.9 vs -2.0, P = 0.005) through week 12 (coprimary endpoint: -3.5 vs -1.6, P < 0.001). Significantly more onabotulinumtoxinA-treated patients achieved 100% (coprimary endpoint) and 50% or greater reductions in UI episodes/day. Decreases in other urinary symptoms were also seen within 1 week with onabotulinumtoxinA that continued through at least week 12. More onabotulinumtoxinA-treated versus placebo-treated patients required no incontinence pads at weeks 1 to 12, and greater improvements in quality of life measurements were seen. Time to request retreatment was significantly longer with onabotulinumtoxinA versus placebo (30.0 weeks vs 13.1 weeks; P < 0.001). No unexpected safety signals were observed. Urinary tract infection was the most commonly observed adverse event., Conclusions: Urinary symptom and quality of life improvements were observed with onabotulinumtoxinA within 1 week of treatment and were sustained for at least 12 weeks., Competing Interests: Conflicts of Interest and Source of Funding: This study and its analysis were sponsored by Allergan plc, Dublin, Ireland. Medical writing and editorial assistance was provided by Jennifer L. Giel, PhD, CMPP, and Karen Pemberton, PhD, CMPP, on behalf of Evidence Scientific Solutions, Inc., Philadelphia, PA, and was funded by Allergan plc, Dublin, Ireland., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc.)

The observation of beam spin asymmetries in two-pion production in semi-inclusive deep inelastic scattering off an unpolarized proton target is reported. The data presented here were taken in the fall of 2018 with the CLAS12 spectrometer using a 10.6 GeV longitudinally spin-polarized electron beam delivered by CEBAF at JLab. The measured asymmetries provide the first opportunity to extract the parton distribution function e(x), which provides information about the interaction between gluons and quarks, in a collinear framework that offers cleaner access than previous measurements. The asymmetries also constitute the first ever signal sensitive to the helicity-dependent two-pion fragmentation function G&#95;{1}^{⊥}. A clear sign change is observed around the ρ mass that appears in model calculations and is indicative of the dependence of the produced pions on the helicity of the fragmenting quark.

A first measurement of the longitudinal beam spin asymmetry A&#95;{LU} in the semi-inclusive electroproduction of pairs of charged pions is reported. A&#95;{LU} is a higher-twist observable and offers the cleanest access to the nucleon twist-3 parton distribution function e(x). Data have been collected in the Hall-B at Jefferson Lab by impinging a 5.498-GeV electron beam on a liquid-hydrogen target, and reconstructing the scattered electron and the pion pair with the CLAS detector. One-dimensional projections of the A&#95;{LU}^{sinϕ&#95;{R}} moments are extracted for the kinematic variables of interest in the valence quark region. The understanding of dihadron production is essential for the interpretation of observables in single-hadron production in semi-inclusive DIS, and pioneering measurements of single-spin asymmetries in dihadron production open a new avenue in studies of QCD dynamics.

The quasifree γ → d → π 0 n ( p ) photon beam asymmetry, Σ , has been measured at photon energies, E γ , from 390 to 610 MeV, corresponding to center of mass energy from 1.271 to 1.424 GeV, for the first time. The data were collected in the A2 hall of the MAMI electron beam facility with the Crystal Ball and TAPS calorimeters covering pion center-of-mass angles from 49 ∘ to 148 ∘ . In this kinematic region, polarization observables are sensitive to contributions from the Δ ( 1232 ) and N (1440) resonances. The extracted values of Σ have been compared to predictions based on partial-wave analyses (PWAs) of the existing pion photoproduction database. Our comparison includes the SAID, MAID and Bonn-Gatchina analyses; while a revised SAID fit, including the new Σ measurements, has also been performed. In addition, isospin symmetry is examined as a way to predict π 0 n photoproduction observables, based on fits to published data in the channels π 0 p , π + n and π - p ., (© The Author(s) 2021.)

We have measured beam-spin asymmetries to extract the sinϕ moment A&#95;{LU}^{sinϕ} from the hard exclusive e[over →]p→e^{'}nπ^{+} reaction above the resonance region, for the first time with nearly full coverage from forward to backward angles in the center of mass. The A&#95;{LU}^{sinϕ} moment has been measured up to 6.6  GeV^{2} in -t, covering the kinematic regimes of generalized parton distributions (GPD) and baryon-to-meson transition distribution amplitudes (TDA) at the same time. The experimental results in very forward kinematics demonstrate the sensitivity to chiral-odd and chiral-even GPDs. In very backward kinematics where the TDA framework is applicable, we found A&#95;{LU}^{sinϕ} to be negative, while a sign change was observed near 90° in the center of mass. The unique results presented in this Letter will provide critical constraints to establish reaction mechanisms that can help to further develop the GPD and TDA frameworks.

The double-polarization observable E and helicity-dependent cross sections σ&#95;{1/2}, σ&#95;{3/2} have been measured for the photoproduction of π^{0} pairs off quasifree protons and neutrons at the Mainz MAMI accelerator with the Crystal Ball/TAPS setup. A circularly polarized photon beam was produced by bremsstrahlung from longitudinally polarized electrons and impinged on a longitudinally polarized deuterated butanol target. The reaction products were detected with an almost 4π covering calorimeter. The results reveal for the first time the helicity- and isospin-dependent structure of the γN→Nπ^{0}π^{0} reaction. They are compared to predictions from reaction models in view of nucleon resonance contributions and also to a refit of one model that predicted results for the proton and for the neutron target. The comparison of the prediction and the refit demonstrates the large impact of the new data.

A common belief is that body mass scaling of metabolic rate results chiefly from intrinsic body-design constraints. However, several studies have shown that multiple ecological factors affect metabolic scaling. The mechanistic basis of these effects is largely unknown. Here, we explore whether abiotic and biotic environmental factors have interactive effects on metabolic scaling. To address this question, we studied the simultaneous effects of temperature and predator cues on the ontogenetic metabolic scaling of amphipod crustaceans inhabiting two different aquatic ecosystems, a freshwater spring and a saltwater lagoon. We assessed effects of phenotypic plasticity on metabolic scaling by exposing amphipods in the laboratory to water with and without fish cues at multiple temperatures. Temperature interacts significantly with predator cues to affect metabolic scaling. Our results suggest that metabolic scaling is highly malleable in response to short-term acclimation. The interactive effects of temperature and predators show the importance of studying effects of global warming in realistic ecological contexts.

We report a measurement of the spin polarization of the recoiling neutron in deuterium photodisintegration, utilizing a new large acceptance polarimeter within the Crystal Ball at MAMI. The measured photon energy range of 300-700 MeV provides the first measurement of recoil neutron polarization at photon energies where the quark substructure of the deuteron plays a role, thereby providing important new constraints on photodisintegration mechanisms. A very high neutron polarization in a narrow structure centered around E&#95;{γ}∼570  MeV is observed, which is inconsistent with current theoretical predictions employing nucleon resonance degrees of freedom. A Legendre polynomial decomposition suggests this behavior could be related to the excitation of the d^{*}(2380) hexaquark.

The weak decay parameter α&#95;{-} of the Λ is an important quantity for the extraction of polarization observables in various experiments. Moreover, in combination with α&#95;{+} from Λ[over ¯] decay it provides a measure for matter-antimatter asymmetry. The weak decay parameter also affects the decay parameters of the Ξ and Ω baryons and, in general, any quantity in which the polarization of the Λ is relevant. The recently reported value by the BESIII Collaboration of 0.750(9)(4) is significantly larger than the previous PDG value of 0.642(13) that had been accepted and used for over 40 years. In this work we make an independent estimate of α&#95;{-}, using an extensive set of polarization data measured in kaon photoproduction in the baryon resonance region and constraints set by spin algebra. The obtained value is 0.721(6)(5). The result is corroborated by multiple statistical tests as well as a modern phenomenological model, showing that our new value yields the best description of the data in question. Our analysis supports the new BESIII finding that α&#95;{-} is significantly larger than the previous PDG value. Any experimental quantity relying on the value of α&#95;{-} should therefore be reconsidered.

We report the first beam-target double-polarization asymmetries in the γ+n(p)→π^{-}+p(p) reaction spanning the nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally polarized deuterons in solid hydrogen deuteride (HD) have been used with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the E polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses and have led to significant revisions for several γnN^{*} resonance photocouplings.

The reactions γp→ηp and γp→η^{'}p are measured from their thresholds up to the center-of-mass energy W=1.96  GeV with the tagged-photon facilities at the Mainz Microtron, MAMI. Differential cross sections are obtained with unprecedented statistical accuracy, providing fine energy binning and full production-angle coverage. A strong cusp is observed in the total cross section for η photoproduction at the energies in the vicinity of the η^{'} threshold, W=1896  MeV (E&#95;{γ}=1447  MeV). Within the framework of a revised ηMAID isobar model, the cusp, in connection with a steep rise of the η^{'} total cross section from its threshold, can only be explained by a strong coupling of the poorly known N(1895)1/2^{-} state to both ηp and η^{'}p. Including the new high-accuracy results in the ηMAID fit to available η and η^{'} photoproduction data allows the determination of the N(1895)1/2^{-} properties.

The double polarization observable E and the helicity dependent cross sections σ&#95;{1/2} and σ&#95;{3/2} were measured for η photoproduction from quasifree protons and neutrons. The circularly polarized tagged photon beam of the A2 experiment at the Mainz MAMI accelerator was used in combination with a longitudinally polarized deuterated butanol target. The almost 4π detector setup of the Crystal Ball and TAPS is ideally suited to detect the recoil nucleons and the decay photons from η→2γ and η→3π^{0}. The results show that the narrow structure previously observed in η photoproduction from the neutron is only apparent in σ&#95;{1/2} and hence, most likely related to a spin-1/2 amplitude. Nucleon resonances that contribute to this partial wave in η production are only N 1/2^{-} (S&#95;{11}) and N 1/2^{+} (P&#95;{11}). Furthermore, the extracted Legendre coefficients of the angular distributions for σ&#95;{1/2} are in good agreement with recent reaction model predictions assuming a narrow resonance in the P&#95;{11} wave as the origin of this structure.

The spin polarizabilities of the nucleon describe how the spin of the nucleon responds to an incident polarized photon. The most model-independent way to extract the nucleon spin polarizabilities is through polarized Compton scattering. Double-polarized Compton scattering asymmetries on the proton were measured in the Δ(1232) region using circularly polarized incident photons and a transversely polarized proton target at the Mainz Microtron. Fits to asymmetry data were performed using a dispersion model calculation and a baryon chiral perturbation theory calculation, and a separation of all four proton spin polarizabilities in the multipole basis was achieved. The analysis based on a dispersion model calculation yields γ(E1E1)=-3.5±1.2, γ(M1M1)=3.16±0.85, γ(E1M2)=-0.7±1.2, and γ(M1E2)=1.99±0.29, in units of 10(-4)  fm(4).

We present new data for the transverse target asymmetry T and the very first data for the beam-target asymmetry F in the γ[over →]p[over →]→ηp reaction up to a center-of-mass energy of W=1.9  GeV. The data were obtained with the Crystal-Ball/TAPS detector setup at the Glasgow tagged photon facility of the Mainz Microtron MAMI. All existing model predictions fail to reproduce the new data indicating a significant impact on our understanding of the underlying dynamics of η meson photoproduction. The peculiar nodal structure observed in existing T data close to threshold is not confirmed.

Information on the size and shape of the neutron skin on (208)Pb is extracted from coherent pion photoproduction cross sections measured using the Crystal Ball detector together with the Glasgow tagger at the MAMI electron beam facility. On exploitation of an interpolated fit of a theoretical model to the measured cross sections, the half-height radius and diffuseness of the neutron distribution are found to be c(n)=6.70±0.03(stat.)  fm and a(n)=0.55±0.01(stat.)(-0.03)(+0.02)(sys.)  fm, respectively, corresponding to a neutron skin thickness Δr(np)=0.15±0.03(stat.)(-0.03)(+0.01)(sys.)  fm. The results give the first successful extraction of a neutron skin thickness with an electromagnetic probe and indicate that the skin of (208)Pb has a halo character. The measurement provides valuable new constraints on both the structure of nuclei and the equation of state for neutron-rich matter.

Precise angular distributions have been measured for the first time for the photoproduction of π0 mesons off neutrons bound in the deuteron. The effects from nuclear Fermi motion have been eliminated by a complete kinematic reconstruction of the final state. The influence of final-state-interaction effects has been estimated by a comparison of the reaction cross section for quasifree protons bound in the deuteron to the results for free protons and then applied as a correction to the quasifree neutron data. The experiment was performed at the tagged photon facility of the Mainz Microtron MAMI with the Crystal Ball and TAPS detector setup for incident photon energies between 0.45 and 1.4 GeV. The results are compared to the predictions from reaction models and partial-wave analyses based on data from other isospin channels. The model predictions show large discrepancies among each other and the present data will provide much tighter constraints. This is demonstrated by the results of a new analysis in the framework of the Bonn-Gatchina coupled-channel analysis which included the present data.

We report the first large-acceptance measurement of polarization transfer from a polarized photon beam to a recoiling nucleon. The measurement pioneers a novel polarimetry technique, which can be applied to many other nuclear and hadron physics experiments. The commissioning reaction of 1H(γ, p)π0 in the range 0.4

The photoproduction of η mesons off nucleons bound in 2H and 3He has been measured in coincidence with recoil protons and recoil neutrons for incident photon energies from threshold up to 1.4 GeV. The experiments were performed at the Mainz MAMI accelerator, using the Glasgow tagged photon facility. Decay photons from the η→2γ and η→3π0 decays and the recoil nucleons were detected with an almost 4π electromagnetic calorimeter combining the Crystal Ball and TAPS detectors. The data from both targets are of excellent statistical quality and show a narrow structure in the excitation function of γn→nη. The results from the two measurements are consistent, taking into account the expected effects from nuclear Fermi motion. The best estimates for position and intrinsic width of the structure are W=(1670±5)  MeV and Γ=(30±15)  MeV. For the first time precise results for the angular dependence of this structure have been extracted.

A precision measurement of the differential cross sections dσ/dΩ and the linearly polarized photon asymmetry Σ≡(dσ⊥-dσ∥)/(dσ⊥+dσ∥) for the γp→π0p reaction in the near-threshold region has been performed with a tagged photon beam and almost 4π detector at the Mainz Microtron. The Glasgow-Mainz photon tagging facility along with the Crystal Ball/TAPS multiphoton detector system and a cryogenic liquid hydrogen target were used. These data allowed for a precise determination of the energy dependence of the real parts of the S- and all three P-wave amplitudes for the first time and provide the most stringent test to date of the predictions of chiral perturbation theory and its energy region of agreement with experiment.

Cross sections for the 3He(e,e' pn)1H reaction were measured for the first time at energy transfers of 220 and 270 MeV for several momentum transfers ranging from 300 to 450 MeV/c. Cross sections are presented as a function of the momentum of the recoil proton and the momentum transfer. Continuum Faddeev calculations using the Argonne V18 and Bonn-B nucleon-nucleon potentials overestimate the measured cross sections by a factor 5 at low recoil proton momentum with the discrepancy becoming smaller at higher recoil proton momentum.

Beam-helicity asymmetries have been measured at the MAMI accelerator in Mainz in the three isospin channels gamma[over -->]p-->pi(+)pi(0)n, gamma[over -->]p-->pi(0)pi(0)p, and gamma[over -->]p-->pi(+)pi(-)p. The circularly polarized photons, produced from bremsstrahlung of longitudinally polarized electrons, were tagged with the Glasgow magnetic spectrometer. Charged pions and the decay photons of pi(0) mesons were detected in a 4pi electromagnetic calorimeter which combined the Crystal Ball detector with the TAPS detector. The precisely measured asymmetries are very sensitive to details of the production processes and are thus key observables in the modeling of the reaction dynamics.

We present the first detailed measurement of incoherent photoproduction of neutral pions to a discrete state of a residual nucleus. The 12C(gamma,pi(0))(12)C*(4.4 MeV) reaction has been studied with the Glasgow photon tagger at MAMI employing a new technique which uses the large solid angle Crystal Ball detector both as a pi(0) spectrometer and to detect decay photons from the excited residual nucleus. The technique has potential applications to a broad range of future nuclear measurements with the Crystal Ball and similar detector systems elsewhere. Such data are sensitive to the propagation of the Delta in the nuclear medium and will give the first information on matter transition form factors from measurements with an electromagnetic probe. The incoherent cross sections are compared to two theoretical predictions including a Delta-hole model.

Objectives: To evaluate two methods of measuring the prostate volume using transrectal ultrasonography. The measurements were performed in vivo at preplanning and again preoperatively in connection with brachytherapy. The accurate measurement of the prostate volume is important in a brachytherapy program for treatment planning., Methods: A total of 43 patients with biopsy-proven prostate cancer underwent prospective determination of the prostate volume, by one physician, using transrectal ultrasonography. Volume calculations were made at the preplanning and preoperative settings, both by a hand-held rectal probe using the prolate ellipsoid formula and by a mounted probe in a stepping device using the planimetric method., Results: The coefficient of variation between the preplanning and preoperative prostate volumes with the probe holder was less than 3% compared with the hand-held probe, which was greater than 10%. The difference between the median values at the preplanning and preoperative settings by serial planimetry was 2.5 cm(3) (range 0.2 to 9.4). The difference in the median volumes between the preplanning and preoperative ellipsoid calculations was 6.7 cm(3) (range 0.3 to 38.7). The difference between the median values with the ellipsoid volume was significant (P <0.001). The Pearson correlation coefficient for all values using the planimetric method was 0.92 versus 0.58 for the ellipsoid method. The correlation coefficient was significantly greater for the planimetric method (P <0.001)., Conclusions: On the basis of these data, planimetric prostate volume determination, by a single ultrasonographer, is an accurate and reproducible method with applicability to a brachytherapy program.

Objectives: To evaluate in a preliminary study the utility of biofeedback for the treatment of the daytime syndrome of urinary frequency and urgency of childhood, a benign, self-limited condition with symptoms that can last for months or years. Observation is a commonly recommended approach to this syndrome because medications and other forms of therapy are often not effective., Methods: During a 2-year period, 89 children (34 boys and 55 girls) presented with this syndrome. Patient age ranged from 4 to 11 years, and duration of symptoms ranged from 1 to 38 months. All children were evaluated with a history, physical examination, urinalysis and culture, and renal and bladder ultrasound scanning. After the evaluation, the parents were offered either observation or surface patch electromyography biofeedback for the problem., Results: Overall, 84 parents (94.3%) selected biofeedback for their child. After 1 month of biofeedback, 34.5% of children were able to achieve a 2 to 4-hour voiding interval. After 2 to 4 months of biofeedback, another 51.2% of patients experienced the same improvement. Overall, 85.7% of children who underwent biofeedback had symptom improvement. In 14.3% of children, no symptom improvement was noted after 4 months of biofeedback and these children were considered nonresponders., Conclusions: The results of this study suggest that biofeedback may be a treatment option for this disorder and warrants further investigation.

Lesch-Nyhan syndrome is a rare genetic disorder characterized by mental retardation, self-mutilation, choreoathetosis, and hyperuricemia. The disease is caused by a mutation in the hypoxanthine-guanine phosphoribosyltransferase gene and is transmitted as a sex-linked recessive disorder. Since hyperuricemia is the primary metabolic problem caused by a hypoxanthine-guanine phosphoribosyltransferase mutation, urologic evaluation and treatment is often necessary for children with this disease. We report a 3-year-old boy who presented with anuric renal failure secondary to bilateral obstructing uric acid calculi. The evaluation of T lymphocytes revealed a hypoxanthine-guanine phosphoribosyltransferase mutation consistent with Lesch-Nyhan syndrome. The diagnosis and urologic management of this disorder is discussed.

Relationships between body storage (estimated as fat content and residuals of body mass regressed against body length) and offspring investment [brood mass, brood size (number of embryos per brood) and embryo mass] were examined within and among populations of the amphipod Gammarus minus in ten cold springs in central Pennsylvania, USA. Two major hypotheses and six corollary hypotheses were tested. Total reproductive investment (brood mass and brood size) was usually strongly positively correlated with maternal body length and body storage both within and among populations. These positive associations between reproductive and somatic investments are expected if individual variation in resource acquisition exceeds that of resource allocation. That is, individuals or populations that are able to acquire more resources should also be able to allocate more resources to both reproduction and somatic reserves than those acquiring fewer resources. This hypothesis is consistent with evidence showing that individual differences in body storage in G. minus and other amphipods are related to differences in resource acquisition. Positive associations between reproductive and somatic investments do not mean that energy costs of reproduction do not exist in G. minus. Evidence for reproductive energy costs included the lower body-fat contents of brooding versus nonbrooding females and the relatively low body mass per length of females who had just deposited eggs in their brood pouch. Unlike brood mass and brood size, individual embryo mass was usually unrelated to maternal body length and body storage. This pattern is largely consistent with optimal offspring investment theory, which predicts that offspring size should be insensitive to variation in parental resource status. However, in contrast to theory, embryo mass increased in winter when brooding females were significantly "fatter", presumably due to the availability of autumn-shed leaf food. This seasonal change in offspring size may be a maternally mediated effect of increased resource availability, though other explanations are possible. Overall, this study suggests that "fatter" female amphipods are fitter than "thinner" ones, though both the costs and benefits of increased body storage and brood size require investigation to substantiate this claim. This study also suggests that effects of individual variation in resource acquisition on life-history patterns deserve more theoretical and empirical attention by ecologists than they have received. It should be recognized that positive and/or nonsignificant correlations between life-history traits are just as interesting and important as are the negative correlations predicted by many theoretical models.

Many types of acrosome induction tests require special equipment and reagents that are not available to most clinicians; thus, simpler tests seem desirable. A modified acrosome induction test has been developed that uses basic reagents and a light microscope, which are available in most office settings. A hypoosmotic swelling test and a double stain (Bismark brown and rose Bengal) were combined to evaluate the viable acrosome reaction (AR) among 74 infertile men and 42 control men. The study included 34 infertile males without varicoceles, 20 with nonrepaired varicoceles and 20 with repaired varicoceles. On each test day, a specimen from a fertile donor was run as a control. The spontaneous acrosome reaction was recorded in semen before and after capacitation. The final % viable acrosome reaction equaled the capacitated value minus the spontaneous value for whole semen. The mean % viable AR among the control specimens was 16% with no values less than 10%. This mean value for controls was significantly greater than the mean % viable AR in each patient group. There were no overlaps in the 95% confidence intervals. When the study group was stratified according to normal acrosome induction tests or >10% viable AR, 30 patients had a normal test and 44 had abnormal tests. Six patients with varicoceles and an abnormal acrosome induction test had a varicocelectomy, and 2 (33%) converted their acrosome induction test to normal after at least 6 months of follow-up. Nine patients had in vitro fertilization (IVF), 3 had a poor result, and all had an abnormal acrosome induction test. Six had a good result with IVF and all 6 had a normal acrosome induction test. Thus, the acrosome induction test described in this report may be performed in any office laboratory to detect subtle male factor problems. The results may be helpful for planning IVF, intracytoplasmic sperm injection, or varicocele surgery for infertile men.

Purpose: Intraoperative sperm banking has been recommended during vasectomy reversal. These specimens are maintained as insurance for possible future intracytoplasmic sperm injection. We evaluated the fate of specimens collected intraoperatively from 48 vasectomy reversal patients., Materials and Methods: Of 75 men 48 (64.0%) agreed to intraoperative sperm banking during vasectomy reversal. A total of 135 vials of epididymal sperm, 81 vials of testicular tissue and 13 vials of vasal sperm were cryopreserved., Results: Among couples who stored sperm 10 (20.8%) voluntarily discarded the specimens within 4 months of vasectomy reversal. Specimens from 31 couples (64.5%) remain in storage. Seven couples (14.6%) have used frozen sperm for intracytoplasmic sperm injection. In 3 of these couples the men were azoospermic after surgery, 2 men had 10,000 to 15,000 sperm per ml. in the ejaculate with limited motility and 2 had 1 to 2 million sperm per ml. with limited motility. The 7 women who underwent intracytoplasmic sperm injection ranged between 37 and 39 years old, which was older than the mean age of the remaining study group (32.7 years). With intracytoplasmic sperm injection fertilization was achieved in all cases and 20 of 47 eggs (42.5%) developed into embryos. Of 7 women 4 achieved biochemical pregnancies (57.1%) and 2 (28.6%) delivered newborns with epididymal sperm. Natural pregnancy occurred in 7 of 16 vasectomy reversal couples (43.7%) who were followed at least 18 months postoperatively but the time to pregnancy averaged 1 year., Conclusions: Cryopreservation of sperm collected at vasectomy reversal is recommended for patients undergoing vasoepididymostomy or vasovasostomy. The couples who used the cryopreserved sperm for intracytoplasmic sperm injection included husbands whose postoperative ejaculate remained azoospermic or severely oligospermic and wives who were approaching 40 years old. Only a limited number of couples (14.6% of the study group) have used the cryopreserved sperm but the delivered newborn rate (28.6%) was comparable to other intracytoplasmic sperm injection data. The natural pregnancy rate after vasectomy reversal was 43.7% but the time to pregnancy after surgery was lengthy (average 1 year). These findings may be helpful for counseling couples who are planning vasectomy reversal surgery and may be considering intraoperative sperm banking.

Purpose: The development of contralateral reflux after unilateral antireflux surgery has spawned interest and controversy regarding etiology and management issues. We evaluate our experience to understand better the issues surrounding contralateral reflux., Materials and Methods: We retrospectively reviewed the records of all children seen in a 7-year period who underwent unilateral extravesical ureteral advancement performed by one of us (M. R. Z.) at our institution., Results: A total of 43 children a mean of 50.5 months old underwent unilateral reimplantation. The male-to-female ratio was 12:31. In 12 children contralateral reflux had resolved preoperatively. Overall contralateral reflux developed in 5 patients (11.6%) after unilateral extravesical ureteral advancement. In 1 child in whom new onset contralateral reflux developed on 1 side reflux resolved by 10 months with observation. In 8 of the 12 children (66%) with a history of resolved contralateral reflux there was no recurrence. In 4 of the 12 children recurrent contralateral reflux completely resolved by 14 months postoperatively with only observation. In these 4 patients initial reflux had been grades II and IV in 2 each. To date all fully evaluable reflux in children with previous contralateral reflux recurred has resolved., Conclusions: The recurrence of contralateral reflux after unilateral reimplantation that is expected in a small number of children resolves in the majority, if not in all, with conservative management. We believe that children should not be offered bilateral reimplantation for unilateral reflux and a history of resolved contralateral reflux. If contralateral reflux recurs, it will most likely resolve with time.

Purpose: Epidermolysis bullosa is a devastating rare disorder that rarely presents with urological complications. We report our experience with and review the literature on this disorder., Materials and Methods: Two brothers with epidermolysis bullosa presented to our center with severe dysuria and urinary tract obstruction caused by meatal stenosis. The obstruction was temporarily relieved by meatotomy but recurrent obstructive skin blistering with severe dysuria required ureterosigmoidostomy for palliation of symptoms., Results: Both children tolerated ureterosigmoidostomy well with 1 requiring bicarbonate supplementation for metabolic acidosis. Ureterosigmoidostomy greatly improved quality of life, and both children have complete symptom relief., Conclusions: Epidermolysis bullosa is usually a severe illness associated with a poor prognosis. Crippling urological symptoms may develop due to recurrent skin blistering causing severe dysuria and secondary obstruction. Ureterosigmoidostomy, despite its complications, provides significant palliation for patients with recalcitrant symptoms.