Measurement of polarization observables T, P, and H in π0 and η photoproduction off quasi-free nucleons.

The target asymmetry T, recoil asymmetry P, and beam-target double polarization observable H were determined in exclusive π0 and η photoproduction off quasi-free protons and, for the first time, off quasi-free neutrons. The experiment was performed at the electron stretcher accelerator ELSA in Bonn, Germany, with the Crystal Barrel/TAPS detector setup, using a linearly polarized photon beam and a transversely polarized deuterated butanol target. Effects from the Fermi motion of the nucleons within deuterium were removed by a full kinematic reconstruction of the final state invariant mass. A comparison of the data obtained on the proton and on the neutron provides new insight into the isospin structure of the electromagnetic excitation of the nucleon. Earlier measurements of polarization observables in the γp→π0p and γp→ηp reactions are confirmed. The data obtained on the neutron are of particular relevance for clarifying the origin of the narrow structure in the ηn system at W=1.68GeV. A comparison with recent partial wave analyses favors the interpretation of this structure as arising from interference of the S11(1535) and S11(1650) resonances within the S11-partial wave.

Measurement of the Gerasimov-Drell-Hearn Integrand for 2H from 200 to 800 MeV.

A measurement of the helicity dependence of the total inclusive photoabsorption cross section on the deuteron was carried out at MAMI (Mainz) in the energy range 200

Measurement of helicity-dependent photoabsorption cross sections on the neutron from 815 to 1825 MeV.

Helicity-dependent total photoabsorption cross sections on the deuteron have been measured for the first time at ELSA (Bonn) in the photon energy range from 815 to 1825 MeV. Circularly polarized tagged photons impinging on a longitudinally polarized LiD target have been used together with a highly efficient 4pi detector system. The data around 1 GeV are not compatible with predictions from existing multipole analyses. From the measured energy range an experimental contribution to the GDH integral on the neutron of [33.9 +/- 5.5(stat) +/- 4.5(syst)] microb is extracted.

Experimental check of the Gerasimov-Drell-Hearn sum rule for 1H.

For the first time we checked the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the proton experimentally in the photon energy range from 0.2-2.9 GeV with the tagged photon facilities at MAMI (Mainz) and ELSA (Bonn). New data of the doubly polarized total cross section difference are presented in the energy range from 1.6 to 2.9 GeV. The contribution to the GDH integral from 0.2-2.9 GeV yields [254+/-5(stat)+/-12(syst)] microb with negative contributions in the Regge regime at photon energies above 2.1 GeV. This trend supports the validity of the GDH sum rule.

First Measurement of the Gerasimov-Drell-Hearn Sum Rule for 1H from 0.7 to 1.8 GeV at ELSA.

To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the first time experimentally, we measured the helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally polarized nucleons in the photon energy range 0.68-1.82 GeV with the tagged photon facility at ELSA. The experiment was carried out with a 4pi detection system, a circularly polarized tagged photon beam, and a frozen spin polarized proton target. The contribution to the GDH sum rule in this photon energy range is [49.9+/-2.4(stat)+/-2.2(syst)] microb.

Measurement of spin-transfer observables in p p-->Lambda Lambda at 1.637 GeV/c.

Spin-transfer observables for p p-->Lambda Lambda have been measured using a transversely polarized frozen-spin target and a beam momentum of 1.637 GeV/c. Current models of the reaction near threshold are in good agreement with existing measurements performed with unpolarized particles in the initial state but produce conflicting predictions for the spin-transfer observables Dnn and Knn (the normal-to-normal depolarization and polarization transfer), which are measurable only with polarized target or beam. Measurements of Dnn and Knn presented here are found to be in disagreement with predictions from these models.

Helicity amplitudes A1/2 and A3/2 for the D13(1520) resonance obtained from the gamma-->p-->-->ppi(0) Reaction.

The helicity dependence of the gamma-->p-->-->ppi(0) reaction has been measured for the first time in the photon-energy range from 550 to 790 MeV. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam, and a longitudinally polarized frozen-spin target. These data are predominantly sensitive to the D13(1520) resonance and are used to determine its helicity amplitudes.

Helicity dependence of gammap --> Npi below 450 MeV and contribution to the Gerasimov-Drell-Hearn sum rule.

The helicity dependence of the single pion photoproduction on the proton has been measured in the energy range from 200 to 450 MeV for the first time. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam, and a frozen-spin target. The data obtained provide new information for multipole analyses of pion photoproduction and determine the main contributions to the Gerasimov-Drell-Hearn sum rule and the forward spin polarizability gamma(0).

Loop I can modulate ADP affinity, ATPase activity, and motility of different scallop myosins. Transient kinetic analysis of S1 isoforms.

The striated muscle myosin of Placopecten moves actin faster in in vitro motility assays and has a higher actin-activated ATPase turnover rate than the myosin of the catch muscle. The heavy chain sequences of the two PlacoS1s are almost identical except at the surface loop 1 near the nucleotide binding pocket, where the two sequences vary significantly. Argopecten striated muscle myosin is 96% identical to Placopecten striated myosin, and both move actin with a similar velocity. To identify the individual kinetic steps which differ between these myosins, we completed a transient kinetic characterization of the three myosin S1s. The two striated S1s have similar rates of nucleotide binding to S1 and to acto.S1. The largest differences between the two are in the rate of ADP dissociation from S1 and affinity of ADP to S1, which differ by a factor of 2. The rates of nucleotide binding, nucleotide dissociation and affinity to nucleotides of the two Placopecten S1s are similar and agree within a factor of 2. In contrast, the affinity of acto.S1 for ADP is nine times weaker for the striated acto.S1 than for the catch acto.S1, compatible with the differences in motility of the Placopectenmyosins. Thus the differences in ADP affinity to acto.S1 and in the in vitro motility can be attributed to the differences in surface loop 1.

Local management of pancreatic carcinoma: iodine-125 implantation.

A retrospective review of patients with pancreatic carcinoma treated from 1983 to 1986 was performed. Group 1 comprise 11 patients judged surgically unresectable who were implanted with iodine-125 followed by external beam therapy post-operatively (Implant + XRT). Eight patients received external beam therapy alone (XRT) Group 2, and 23 patients underwent radical surgical resection (group 3). Median survival was 8 months in the implant + XRT group; 5 months in the XRT alone group and 7.5 months in the surgical group. Locoregional control was achieved in 8/11 (73%), 2/8 (25%), and 11/23 (48%) of these groups respectively. Pain was the most common presenting symptom, 38/42 (90%). Complete, lasting palliation was achieved in 8/10 (80%) of group one, 2/8 (25%) of group two, and 13/20 (65%) of group three patients. Despite surgical unresectability implant + XRT appears to offer similar results to radical surgery. The data are presented with respect to the implant technique, disappearance of the tumour on CT scan and patterns of failure.

Discharge planning for the breastfeeding dyad.

The increase in early hospital dismissal of postpartum mothers has dramatically decreased the amount of time available for teaching of breastfeeding.

Even children have arthritis.

Children experience a number of problems related to juvenile rheumatoid arthritis (JRA), including pain, stiffness, and loss of mobility that interferes with normal growth and development. Innovative nursing in a variety of settings is needed to manage the child with this chronic illness.

Deep hypothermic arrest in children undergoing heart surgery.

Deep hypothermia with cold cardioplegia is a technique that increases the chances for successful palliative or reparative cardiac surgery for the critically ill infant or child with complex or severe cardiac anomalies. Perioperative nursing care is of vital importance to the child, family, and operative team. Nursing care measures include perioperative teaching as well as preoperative and postoperative physical assessment of the child and psychosocial assessment of the child and family unit. An understanding of the advantages and the potential complications of hypothermic techniques enhances the nurse's ability to carry out these nursing interventions.