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We have measured the longitudinal analyzing power Az of the pp→ppπ0 reaction at 375 MeV bombarding energy. We find that for certain angle combinations of the outgoing particles the observed Az is as large as 0.3, demonstrating that sizeable longitudinal analyzing powers in reactions with multi-particle final states are possible. This result has implications for pp parity violation experiments above the pion threshold. The observed Az is dominated by the interference between s and p wave pions in conjunction with nucleon-nucleon P waves in the final state.

We describe an experimental setup for the measurement of polarization observables in pion production near threshold. Experiments carried out with this facility use a polarized proton beam in the Indiana University Cooler storage ring, and an internal, polarized hydrogen target. The detector system measures energy, direction and velocity of multiple outgoing charged particles that are within a forward cone of about 32° opening angle. An array of scintillators also allows the detection of neutrons. In addition to the technical details of the apparatus, we describe the procedure for data acquisition, as well as some aspects of the analysis.

We report a measurement of the spin-dependent total cross section ratios {delta}{sigma}{sub T}/{sigma}{sub tot} and {delta}{sigma}{sub L}/{sigma}{sub tot} of the pp{yields}pp{pi}{sup 0} reaction between 325 and 400 MeV. The experiment was carried out with a polarized internal target in a storage ring. Nonvertical beam polarization was obtained by the use of solenoidal spin rotators. Near threshold, the knowledge of both spin-dependent total cross sections is sufficient to deduce the strength of certain participating partial waves, free of any model. (c) 1999 The American Physical Society.

A beam profile monitor based on the deflection of a probe electron beam by the electric field of a stored, electron-cooled proton beam is described and first results are presented. Electrons were transported parallel to the proton beam by a uniform longitudinal magnetic field. The probe beam may be slowly scanned across the stored beam to determine its intensity, position, and size. Alternatively, it may be scanned rapidly over a narrow range within the interior of the stored beam for continuous observation of the changing central density during cooling. Examples of a two dimensional charge density profile obtained from a raster scan and of a cooling alignment study illustrate the scope of measurements made possible by this device.

A polarized internal atomic-hydrogen target and a stored, polarized beam are used to measure the spin-dependent total cross section {Delta}{sigma}{sub T}thinsp/{sigma}{sub tot} for {rvec p}{rvec p}{r_arrow} pp{pi}{sup 0} , as well as the polar integrals of the spin correlation coefficient combination A{sub xx}{minus}A{sub yy} , and the analyzing power A{sub y} at four bombarding energies between 325 and 400thinspthinspMeV. This experiment is made possible by the use of a cooled beam in a storage ring. The polarization observables are used to study the contribution from individual partial waves. {copyright} {ital 1998} {ital The American Physical Society }

We have measured the $\mathrm{pp}$ spin correlation coefficients ${A}_{\mathrm{xx}},$ ${A}_{\mathrm{yy}},$ ${A}_{\mathrm{xz}}$ and the analyzing power ${A}_{y}$ at 250.0, 280.0, 294.4, 310.0, 350.0, 399.1, and 448.9 MeV over the laboratory angular range $3.5\ifmmode^\circ\else\textdegree\fi{}--43.5\ifmmode^\circ\else\textdegree\fi{}$ $({\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}=7\ifmmode^\circ\else\textdegree\fi{}--90\ifmmode^\circ\else\textdegree\fi{}).$ The statistical accuracy is approximately $\ifmmode\pm\else\textpm\fi{}0.006$ for ${A}_{y}$ and $\ifmmode\pm\else\textpm\fi{}0.02$ for ${A}_{\mathrm{mn}}$ per $1\ifmmode^\circ\else\textdegree\fi{}$ angle bin, while the corresponding scale factor uncertainties are 1.3 and 2.5 %, respectively. The experiment makes use of a polarized hydrogen gas target internal to a proton storage ring (IUCF Cooler) and a circulating beam of polarized protons. The method of calibration relative to pp spin correlation coefficients and analyzing power at 197.4 MeV, the injection energy, involves up and down ramping of the energy of the polarized beam. The data are compared to recent $\mathrm{pp}$ partial waves analyses and $\mathrm{NN}$ potential models, emphasizing in particular the energy dependence in the region of the pion production threshold.

Measurements of $\mathrm{pp}$ spin correlation coefficients ${A}_{\mathrm{xx}},$ ${A}_{\mathrm{yy}},$ and ${A}_{\mathrm{xz}}$ and analyzing power ${A}_{y}$ for $\mathrm{pp}$ elastic scattering at 197.4 MeV over the laboratory angular range 3.5 \ifmmode^\circ\else\textdegree\fi{}--43.5 \ifmmode^\circ\else\textdegree\fi{} $({\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}=7\ifmmode^\circ\else\textdegree\fi{}--90\ifmmode^\circ\else\textdegree\fi{})$ have been carried out. The typical statistical accuracy per 1$\ifmmode^\circ\else\textdegree\fi{}$ angle bin is better than 0.02 for the ${A}_{\mathrm{mn}}$ and better than 0.005 for ${A}_{y}.$ Systematic errors are negligible except for an overall normalization uncertainty of 2.5% for ${A}_{\mathrm{mn}}$ and 1.3% for ${A}_{y}.$ The experiment makes use of a polarized hydrogen gas target internal to a proton storage ring (IUCF Cooler) and a circulating beam of polarized protons. The target polarization is switched in sign and direction $(x,y,z)$ every 2 s by reversing a weak guide field $(\ensuremath{\approx}0.3$ mT). Scattered and recoil protons are detected in coincidence by two sets of wire chambers, by scintillators, and by silicon-strip recoil detectors placed 5 cm from the proton beam. Analysis methods and comparison to recent $\mathrm{pp}$ partial-wave analyses and $\mathrm{NN}$ potential models are described.

We have measured the pd elastic scattering with an electron-cooled beam of a proton storage ring and an internal jet target operated with HD gas. The accurately known H/D ratio is used to transfer the precision of existing pp scattering data to the pd cross sections. Measurements were performed for proton energies between 200 and 300 MeV in the angular range 11°

With a storage ring synchrotron, two additional methods have become possible to establish polarization standards at arbitrary energies, making use of the ease with which the energy of the stored beam can be changed. Both methods yield the analyzing power of a reaction at one energy in relation to the known analyzing power at a different energy. One method involves ramping of the energy of a polarized beam up and down; the other requires a polarized target. The two methods have been demonstrated in an experiment with the Indiana Cooler, and their relative consistency has been established.

We have measured the time dependence of the polarization of a stored proton beam near an intrinsic depolarizing resonance. The distance to the resonance was varied by changing the vertical tune of the storage ring. The measurements are consistent with exponential decay and with a simple model for the change of the lifetime as the resonance is approached. It was originally expected that the presence of an internal target stimulates depolarization; however, we found no evidence for such an effect.

Measurements of the $\mathrm{pp}$ spin correlation coefficients ${A}_{\mathrm{xx}},$ ${A}_{\mathrm{yy}},$ and ${A}_{\mathrm{xz}}$ and analyzing power ${A}_{y}$ for $\mathrm{pp}$ elastic scattering at 197.8 MeV over the angular range $4.5\ifmmode^\circ\else\textdegree\fi{}$--$17.5\ifmmode^\circ\else\textdegree\fi{}$ have been carried out. The statistical accuracy is approximately $\ifmmode\pm\else\textpm\fi{}0.01$ for ${A}_{\mathrm{mn}}$ and $\ifmmode\pm\else\textpm\fi{}0.004$ for ${A}_{y},$ while the corresponding scale factor uncertainties are 2.4% and 1.3%, respectively. The experiment makes use of a polarized hydrogen gas target internal to a proton storage ring (IUCF Cooler) and a circulating beam of polarized protons. The target polarization $(Q=0.79)$ is switched in sign and in direction $(x,y,z)$ every 2 s by reversing a weak guide field (about 0.3 mT). The forward-scattered protons are detected in two sets of wire chambers and a scintillator, while recoil protons are detected in coincidence with the forward protons by silicon strip detectors placed 5 cm from the proton beam. The background rate from scattering by the walls of the target cell is $(0.2\ifmmode\pm\else\textpm\fi{}0.2)$% of the good event rate. Analysis methods and comparisons with $\mathrm{pp}$ potential models and $\mathrm{pp}$ partial wave analyses are described.

A storage cell has been constructed for use as an internal polarized gas target in the storage ring at the Indiana University Cyclotron Facility. The storage cell has thin teflon walls which allow for detection of low energy recoil particles. We report on nuclear polarization measurements of hydrogen atoms, produced by an atomic beam source, in this storage cell. The results indicate that a target polarization in excess of 0.70 is achieved. We discuss the design and construction details of a storage cell target and the polarization results which are based on low-energy pp spin correlation measurements using the University of Wisconsin tandem accelerator.

The total cross section and angular distributions for the differential cross section and the analyzing power of the exclusive two-body pion production reaction $^{12}\mathrm{C}$(p\ensuremath{\rightarrow},${\mathrm{\ensuremath{\pi}}}^{0}$) $^{13}\mathrm{N}_{\mathrm{g}.\mathrm{s}.}$ have been measured at 147 MeV, very near the threshold energy of 145 MeV. Both the large forward-backward asymmetry in the angular distribution of the differential cross section and the large values observed for the analyzing powers indicate strong interference between the amplitude for s-wave pion emission and the amplitudes for p-wave pion emission. A phase-shift analysis performed on these new data yields significant p-wave strength at this low energy. The measurements for ${\mathrm{\ensuremath{\pi}}}^{0}$ production from carbon are in agreement with results extracted from existing data for ${\mathrm{\ensuremath{\pi}}}^{+}$ production from carbon, after corrections for isospin invariance and Coulomb effects. The reduced s-wave strength is found to have a simple power law dependence on the total number of nucleons in the final bound state.

A device is described which employs a weak electron probe beam to measure moments of the distribution of a coasting charged particle beam in a storage ring through the beam-beam electromagnetic interaction. The electron beam is confined by a longitudinal magnetic field in a solenoid and guided by electrostatic steering elements. Displacement of the probe beam is observed with a position-sensing collector. The results of initial tests are reported. The stored beam intensity can be monitored with a sensitivity of a few μA, approaching that of commercial dc transformers, or the position can be determined to a precision of better than 0.3 mm. By placement in a ring region having large dispersion, the device also serves as a useful beam momentum monitor. With a further reduction of probe beam diameter, this device may become useful as a monitor of changes in cooled beam emittance.

Measurements have been made in the Cooler ring at the Indiana University Cyclotron Facility (IUCF) of the mean lifetime of stored and electron-cooled proton beams in the presence of various target gas species at two ring locations differing in dispersion. A broad range of beam energy Tb, target atomic number Zt and thickness xt was employed. The loss (removal) cross sectionσL per target atom, extracted from the lifetime measurement, exhibits a minimum for small xt which is found to scale with ( Z t T b ) 2 . This behavior is expected because forward Coulomb scattering from target nuclei should be the dominant loss mechanism under the conditions of measurement. A marked increase in σL for larger xt is attributed to emittance growth arising from multiple scattering in competition with the transverse cooling rate. Lattice dispersion at the target increases the contribution to beam heating by electrons in the target atoms and introduces an additional loss mechanism. From the measured σL and beam lifetime, a time cycle may be selected which gives the optimum time-averaged luminosity for a given experiment. Scaling of σL allows prediction of the optimum luminosity over the full operating regime of the cooling ring.

The use of thin fibers as internal targets for nuclear physics experiments in storage rings is discussed. We have measured the lifetime and the energy spread of stored, electron-cooled beams in the presence of an internal carbon fiber target. Measurements have been carried out in the Indiana Cooler with proton beams between 100 MeV and 300 MeV. The effect of the inhomogeneous fiber target on the beam is the same as that of a homogeneous gas target of equivalent thickness within the accuracy of the measurement. The measurements are compared with a Monte Carlo simulation of the stored beam. It is demonstrated that charging of the fiber target can significantly affect the lifetime and energy spread of the stored beam.

Stored ion beams offer the possibility to use polarized internal targets that consist of a source of polarized atoms in conjunction with a long, narrow, windowless target cell to enhance the target thickness. In this paper, we discuss the effect of such a cell on the performance of the storage ring, based on measurements carried out with the Indiana Cooler. A prototype target cell was constructed and was operated with a controlled flow of H2 target gas in a beam of stored protons. Detection of protons scattered at angles from 4° to 15° in coincidence with the associated recoil particles was used to identify elastic scattering. The results show that the presence of a 25 cm long target cell with a rectangular opening of 6.4 mm by 7.9 mm is compatible with operation of the Cooler ring. This demonstrates the feasibility of an important component of experiments with stored, polarized beams and carrier-free polarized, internal targets.

Total cross sections and angular distributions for the differential cross section and analyzing power of the reaction $^{2}\mathrm{H}$(p\ensuremath{\rightarrow},${\mathrm{\ensuremath{\pi}}}^{0}$${)}^{3}$He have been measured at four energies very near threshold (0.1${\mathit{T}}_{\mathrm{\ensuremath{\pi}}}^{\mathrm{c}.\mathrm{m}.}$2.7 MeV). The large asymmetries observed in the angular distributions of the differential cross section indicate strong constructive interference between the amplitudes for s-wave pion emission and the amplitudes for p-wave emission. A measure of the s-wave strength at zero energy is obtained and found to be consistent with the results from pionic atoms. The new data indicate that the excitation function for this reaction differs significantly from that of p+n\ensuremath{\rightarrow}d+${\mathrm{\ensuremath{\pi}}}^{0}$.

Making use of an electron-cooled beam in the IUCF storage ring, we have measured the total cross section σ tot for pp→pp π 0 at 31 bombarding energies between 285 and 325 MeV. At a level of about 5%, the data show no fluctuations that could be associated with the onset of other pion production channels. A calculation of the single-partial-wave cross section σ ss , including direct production only (no rescattering), falls short of the experiment by a factor of 5.2±0.3, but reproduces the observed energy dependence when scaled. This energy dependence is explained by contributions from the phase-space factor and the final-state interaction between the outgoing nucleons. The relative importance of higher partial waves is deduced from the energy dependence of σ tot as well as from the angular distributions of reaction protons.

Differential cross sections for the neutral pion production reaction {sup 12}C({ital p},{pi}{sup 0}){sup 13}N{sub g.s.} have been measured at 153.5, 166.1, 186.0, and 204.0 MeV bombarding energy using recoil detection. The shape of the angular distribution agrees well with that of the mirror reaction {sup 12}C({ital p},{pi}{sup +}){sup 13}C{sub g.s.}. Isospin invariance predicts for the ratio of the cross sections {sigma}({ital p},{pi}{sup +})/{sigma}({ital p},{pi}{sup 0})=2. At 153.5, 166.1, and 186.0, MeV, where ({ital p},{pi}{sup +}) cross sections have been reported previously by other groups at the same reduced pion momentum {eta}={ital p}{sub {pi}}/{ital m}{sub {pi}}{ital c}=0.34,0.55,0.78, the ratio of the total cross sections is 2.02{plus minus}0.14, 3.14{plus minus}0.12, and 2.12{plus minus}0.16, respectively. The ({ital p},{pi}{sup 0}) cross sections at 166 MeV is therefore 1.57{plus minus}0.06 times larger than expected. For {ital T}{sub {ital p}}{lt}160 MeV, the experimental cross sections are larger than predicted by a phase space and Coulomb barrier penetration calculation that fits the higher-energy data. Differential cross sections were also obtained for the {sup 12}C({ital p},{pi}{sup {minus}}){sup 13}O reaction, and upper limits set for differential cross sections for radiative capture to the ground state of {sup 13}N.

The analyzing power {ital A}{sub {ital y}}({theta}) for {ital pp} elastic scattering at 185.4 MeV has been measured with a new technique in which the polarized beam in a storage ring was scattered from an internal H{sub 2} gas target. The measurement covered the angular range {theta}{sub c.m.}=5.45{degree}--21.36{degree}, where {ital A}{sub {ital y}} is dominated by interference between Coulomb and nuclear amplitudes. It is found that electromagnetic spin-orbit effects are required to explain the data. The present measurement demonstrates for the first time the feasibility and the advantages of nuclear physics experiments with polarized beams in storage rings.

Although still a relatively new development, exploitation of the technology of storage rings has been playing an increasing role in the field of nuclear science. These few remarks present a subjective view of some of the progress and problems in this ring application.

The analyzing power ${\mathit{A}}_{\mathit{y}}$ for p+p elastic scattering at ${\mathrm{\ensuremath{\theta}}}_{\mathrm{lab}}$=8.64\ifmmode^\circ\else\textdegree\fi{}\ifmmode\pm\else\textpm\fi{}0.07\ifmmode^\circ\else\textdegree\fi{} (${\mathrm{\ensuremath{\theta}}}_{\mathrm{cms}}$=18.1\ifmmode^\circ\else\textdegree\fi{}) and at a bombarding energy of 183.1\ifmmode\pm\else\textpm\fi{}0.4 MeV has been determined to be ${\mathit{A}}_{\mathit{y}}$=0.2122\ifmmode\pm\else\textpm\fi{}0.0017. The error includes statistics, systematic uncertainties, and the uncertainty in bombarding energy and angle. This measurement represents a calibration standard for polarized beams in this energy range. The absolute scale for the measurement has been obtained by comparison with p+C elastic scattering at the same energy at an angle where ${\mathit{A}}_{\mathit{y}}$ is very nearly unity.

One barrier to the attainment of a crystalline ordered state for a well-cooled beam in a storage ring will be the viscous heating by the shear induced in the bending fields of the ring. Shear will transfer some of the energy of coherent motion to thermal energy and may prevent reaching the very low temperatures required for formation of the ordered state. A concept for a ring is proposed in which shear within a monoenergetic beam of finite size is substantially reduced by means of combined electrostatic and magnetic fields within the bending elements.

The total cross section for the reaction pp\ensuremath{\rightarrow}pp${\mathrm{\ensuremath{\pi}}}^{0}$ was measured at nine center-of-mass energies from 1.5 to 23 MeV above threshold. The experiment was carried out with the Indiana Cooler, a recently constructed storage ring. The experimental advantages of an electron-cooled proton beam were utilized. The data cover an energy range where only the lowest possible angular momentum state contributes in the exit channel. The measured energy dependence of the total cross section is not compatible with that predicted by models of s-wave pion production and rescattering.

51Chromium release-derived cytotoxicity data yield curvilinear plots when the x axis displays the effector:target ratio and the y axis displays the percentage of cytotoxicity. To facilitate data analysis, several biomathematical models (simple linear regression, exponential fit, and Von Krogh) have been used to express these cytotoxicity curves as a single numerical value, termed the lytic unit. Other than using raw cytotoxicity data, the lytic unit has been the most common method of data presentation in human and animal tumor immune studies involving natural killer cells, lymphokine-activated killer cells, and cytotoxic T cells. Unfortunately, the models for determining lytic unit values incorporate assumptions and methods of calculation that can result in inaccurate model-predicted cytotoxicity in comparison with the actual observed cytotoxicity data. Even when the model is accurate in predicting cytotoxicity values (i.e., the nonlinear regression-calculated three-parameter Von Krogh model), comparisons between donors of minimally different or highly different cytotoxicity are still fraught with potential error due to statistically verifiable violations of assumptions of parallelism. Although more cumbersome, donor cytotoxicity comparisons using a range of effector:target ratios are not subject to the above problems. Researchers may therefore want to reconsider the use of lytic units when evaluating and reporting cytotoxicity data.

The time dependence of the polarization of a stored proton beam was measured near an induced depolarizing resonance. The resonance was created by a magnetic field which oscillated along the beam axis. The distance to the resonance was varied by changing the frequency of the oscillating field. The resonance was approached from either side and the time dependence of the polarization was found to be symmetric with respect to the resonance, and in agreement with an earlier measurement that involved an intrinsic depolarizing resonance.

We have measured three axial polarization observables in d-->p--> breakup with a polarized 270 MeV deuteron beam on a polarized proton target. Axial observables are zero by parity conservation in elastic scattering but can be easily observed in the breakup channel at the present energy. Based on a symmetry argument, the sensitivity of these observables to the three-nucleon force might be enhanced. Calculations without three-nucleon force are in fair agreement with our measurement, indicating that the expected sensitivity of axial observables to the three-nucleon force is not confirmed. Including a three-nucleon force in the calculation does not improve the agreement with the data.

We have measured three axial polarization observables in d--p--breakup with a polarized 270 MeV deuteron beam on a polarized proton target. Axial observables are zero by parity conservation in elastic scattering but can be easily observed in the breakup channel at the present energy. Based on a symmetry argument, the sensitivity of these observables to the three-nucleon force might be enhanced. Calculations without three-nucleon force are in fair agreement with our measurement, indicating that the expected sensitivity of axial observables to the three-nucleon force is not confirmed. Including a three-nucleon force in the calculation does not improve the agreement with the data.

A research program with the aim of investigating the spin dependence of the three-nucleon continuum in pd collisions at intermediate energies was carried out at IUCF using the Polarized INternal Target EXperiments (PINTEX) facility. In the elastic scattering experiment at 135 and 200 MeV proton beam energies a total of 15 independent spin observables were obtained. The breakup experiment was done with a vector and tensor polarized deuteron beam of 270 MeV and an internal polarized hydrogen gas target. We developed a novel technique for the analysis of the breakup observables, the sampling method. The new approach takes into account acceptance and non-uniformities of detection efficiencies and is suitable for any kinematically complete experiment with three particles in the final state., Comment: Contribution to the 19th European Few-Body Conference, Groningen Aug. 23-27, 2004

The proton and deuteron analyzing powers and 10 of the possible 12 spin correlation coefficients have been measured for p+d elastic scattering at proton bombarding energies of 135 and 200 MeV. The results are compared with Faddeev calculations using two different NN potentials. The qualitative features of the extensive data set on the spin dependence in p+d elastic scattering over a wide range of angles presented here are remarkably well explained by two-nucleon force predictions without inclusion of a three-nucleon force. The remaining discrepancies are, in general, not alleviated when theoretical three-nucleon forces are included in the calculations., Comment: 43 pages, 12 figures, accepted for publication by Phys. Rev. C

We have measured the vector and tensor polarization of an atomic deuterium target as a function of the target density. The polarized deuterium was produced in an atomic beam source and injected into a storage cell. For this experiment, the atomic beam source was operated without rf transitions, in order to avoid complications from the unknown efficiency of these transitions. In this mode, the atomic beam is vector and tensor polarized and both polarizations can be measured simultaneously. We used a 1.2-cm-diam and 27-cm-long storage cell, which yielded an average target density between 3 and 9x10{sup 11} at/cm{sup 3}. We find that the tensor polarization decreases with increasing target density while the vector polarization remains constant. The data are in quantitative agreement with the calculated effect of spin exchange between deuterium atoms at low field.

The IUCF (Indiana University Cyclotron Facility) Cooler is a synchrotron-storage ring with electron cooling. The construction was funded in 1983, with beam tests beginning in 1987. After a year to commissioning, the ring is beginning to provide beams for research users. The author reviews some of the recent accomplishments and summarizes some of the operating characteristics as presently understood. The IUCF Cooler is in transition to operational status with first experiments underway and an appreciable fraction of its large parameter space explored. There have been signs of good resolution, small emittance, good reproducibility, and easy energy variability. >

A measurement of the total cross section for the reaction pd → pdπ° very close to threshold has been carried out at the IUCF Cooler. The deuteron with its known "nuclear structure" is the simplest system where pion production on nuclei can be investigated and mechanisms other than the quasi-free production may become important. In this contribution the experimental setup and the data analysis are described. Total cross sections for pd → pdπ° in the range 0.1 < η < 1.0 are reported.

Developed equipment consisted of a high magnetic field solenoid with supporting instrumentation for electron plasma confinement. The solenoid was designed and delivered in year 1. In year 2, it was mapped and the trap was created and commissioned. In parallel, an ongoing program of beam-plasma interaction studies was carried out with a lower field trap developed earlier. The trap was placed in the IUCF Coolor (an intermediate-energy electron-cooled storage ring) and the effects of the beam on the plasma were investigated, including energy and angular momentum transfer. Student projects carried out within the beam-plasma group also included development of a diagnostic with high spatial resolution, and preparation for extension of the beam-plasma interaction study to much lower beam energy. This became the principal group activity during the latter part of the project.

National Cancer Center Network (NCCN) and Society of Surgical Oncology (SSO) practice guidelines recommend chest computed tomography (CT) as part of the staging evaluation of patients with extremity soft tissue sarcoma (STS). In the current study, the authors evaluated the use and yield of chest roentgenography (CXR) and selective chest CT to screen for pulmonary metastases in patients with T1 STS.The utility of these staging studies was evaluated retrospectively in a cohort of 125 consecutive patients who presented to a tertiary care cancer center with T1 primary (nonrecurrent) extremity STS. Two diagnostic strategies (CXR alone vs. CXR plus chest CT) were evaluated using an incremental cost-effectiveness ratio.The majority of tumors (70%) were high grade. The median sarcoma size was 3.0 cm; 64 of the tumors (51%) were located deep to the investing fascia of the extremity. All patients underwent staging CXR; 1 CXR (1%) was suspicious for metastatic disease. Fifty-one patients (41%) also underwent chest CT; 1 chest CT, performed in the patient with a suspicious CXR, revealed metastatic disease. With a median follow-up of 76 months, 19 patients (15%) developed metachronous pulmonary metastases. The relatively low yield resulted in an incremental cost-effectiveness ratio of $59,772 per case of synchronous pulmonary metastasis detected by CXR plus chest CT.Less than 1% of patients with T1 primary extremity STS were found to have pulmonary metastases that were detectable using a staging algorithm that employs routine CXR with the selective use of chest CT. The findings of the current study do not support current NCCN or SSO practice guidelines for patients with high-grade T1 STS.

Heregulin (HRG) belongs to a family of polypeptide growth factors that bind to receptor tyrosine kinases ErbB3 and ErbB4. HRG binding induces ErbB3 and ErbB4 heterodimerization with ErbB2, activating downstream signal transduction. Vascular endothelial growth factor (VEGF) is a primary regulator of physiological angiogenesis and is a major mediator of pathological angiogenesis, such as tumor-associated neovascularization. In this study, we demonstrate that HRG-beta1 increased secretion of VEGF from breast cancer cells in a time- and dosage-dependent manner and that this increase resulted from up-regulation of VEGF mRNA expression via transcriptional activation of the VEGF promoter. Deletion and mutational analysis revealed that a CA-rich upstream HRG response element located between nucleotide-2249 and -2242 in the VEGF promoter mediated HRG-induced transcriptional up-regulation of VEGF. While investigating the downstream signaling pathways involved in HRG-mediated up-regulation of VEGF, we found that HRG activated extracellular signal-regulated protein kinases, Akt kinase, and p38 mitogen-activated protein kinase (MAPK). However, only the specific inhibitor of p38 MAPK (SB203580), not extracellular signal-regulated kinase inhibitor PD98059 nor the inhibitor of phosphatidylinositol 3-kinase-Akt pathway (Wortmannin), blocked the up-regulation of VEGF by HRG. The HRG-stimulated secretion of VEGF from breast cancer cells resulted in increased migration of murine lung endothelial cells, an activity that was inhibited by either VEGF-neutralizing antibody or SB203580. These results show that HRG can activate p38 MAPK to enhance VEGF transcription via an upstream HRG response element, leading to increased VEGF secretion and angiogenic response in breast cancer cells.

Alveolar soft part sarcoma (ASPS) is a rare form of soft tissue sarcoma. Brain metastases have been reported to be a common feature of Stage IV ASPS, and recent practice guidelines recommend routine intracranial imaging as part of the staging evaluation in all patients who present with ASPS.The authors performed a comprehensive retrospective review of the clinical presentation, treatment, outcome, and patterns of failure in a consecutive series of patients with localized (American Joint Committee on Cancer [AJCC] Stages II/III) or metastatic (AJCC Stage IV) ASPS who presented to a tertiary care cancer center between 1959 and 1998.Seventy-four patients were identified from the database searches. The anatomic distribution of their primary tumors included: extremities, 44 patients (60%); trunk, 15 patients (20%); head and neck, 9 patients (12%); and retroperitoneum, 6 patients (8%). The median tumor size was 6.5 cm (range, 1.2-24 cm). The AJCC stage at presentation was Stage II or III in 35% of the patients and Stage IV in 65% of the patients. The 5-year actuarial local recurrence free, distant recurrence free, disease free, and overall survival rates among the 22 patients with localized ASPS were 88%, 84%, 71%%, and 87%, respectively. At a median follow-up of 9 years, 2 of 22 patients with localized disease had developed local recurrences and 3 had developed metastatic disease (all to the lung only). Brain metastases were noted in 9 of 48 patients who presented with Stage IV (M1) disease (19%) and always were noted in association with metastasis to other sites. The median survival of patients with M1 disease was 40 months, with a 5-year survival rate of 20%.Long term follow-up of patients with localized ASPS reveals a relatively indolent clinical course with relatively low rates of local and distant recurrence. In patients with Stage IV ASPS, brain metastases were observed only as part of more disseminated disease. The observations of the current study do not support current practice guidelines for the staging of patients with ASPS and suggest that selective rather than routine intracranial imaging should be used in patients presenting with ASPS.

The nuclear polarization of H(2) molecules formed by recombination of polarized H atoms on a Cu surface was measured as a function of external magnetic field and of temperature of the surface. The proton polarization of the molecules was determined by scattering of a longitudinally polarized 203-MeV proton beam in the Indiana University Cyclotron Facility storage ring. The nuclear polarization of the molecules, relative to the polarization of the atoms before recombination, increased from near zero in a weak magnetic field to 0.42 +/- 0.02 in a 0.66 T field. A simple model of the relaxation accounts quantitatively for the observations.

Cystosarcoma phyllodes is a rare sarcoma of the breast. Although surgical removal is the mainstay of treatment, the extent of surgery required (excision vs. mastectomy) and the need for additional local therapy, such as radiotherapy, are unclear. The current study evaluated the rate of local and distant failure, as well as potential prognostic factors, to better define appropriate treatment strategies.One hundred one patients treated primarily for cystosarcoma phyllodes of the breast were evaluated. These tumors were classified histologically into benign (58%), indeterminate (12%), and malignant (30%) based on well defined criteria. Stromal overgrowth (29%) was considered separately. Surgery was comprised of local excision with breast conservation (47%) or mastectomy (53%). Microscopic surgical margins were negative in 99% of cases. Six patients received adjuvant radiotherapy.Overall survival for the 101 patients was 88%, 79%, and 62% at 5, 10, and 15 years, respectively. For patients with nonmalignant (benign or indeterminate) and malignant cystosarcoma phyllodes, the overall survival was 91% and 82%, respectively, at 5 years, and 79% and 42%, respectively, at 10 years. Similar rates were observed based on the presence or absence of stromal overgrowth. Local recurrence occurred in 4 patients, with an actuarial 10-year rate of 8%. Eight patients developed distant metastases, with an actuarial 10-year rate of 13%. Multivariate analysis using Cox proportional hazards regression revealed stromal overgrowth to be the only independent predictor of distant failure.Local failure in this group of largely margin negative patients with cystosarcoma phyllodes of the breast was low, showing that breast-conserving surgery with appropriate margins is the preferred primary therapy. The current study data do not support the use of adjuvant radiotherapy for patients with adequately resected disease. Patients with stromal overgrowth, particularly when the tumor size was5 cm, were found to have a high rate of distant failure; such patients merit consideration of a trial that examines the efficacy of systemic therapy.

Our recent studies (R. Pollock et al., Clin. Cancer Res., 4: 1985-1994, 1998; M. Milas et al., Cancer Gene Ther., in press, 2000) have shown that the restoration of wild-type (wt) p53 enhances cell cycle control in vitro and inhibits the growth of human soft-tissue sarcoma in severe combined immunodeficient mice. We hypothesized that the antitumor effect of wt p53 overexpression in sarcoma cells is attributable not only to enhanced cell cycle control but also to inhibition of angiogenesis. We evaluated the effect of restoring wt p53 function on angiogenesis in human soft-tissue sarcoma harboring mutant p53. Restoration of wt p53 expression in human leiomyosarcoma SKLMS-1 cells that contain mutant p53 markedly inhibited angiogenesis induced by tumor cells in vivo. Angiogenesis assays using an in vivo Matrigel plug assay demonstrated that less neovascularization in severe combined immunodeficient mice was observed with conditioned medium (CM) from human synovial sarcoma cells expressing wt p53 compared with CM from human synovial sarcoma cells expressing mutant p53. Microvessel density and microvessel counts were lower in tumor xenografts from cells containing wt p53 than in tumor xenografts from cells containing mutant p53. The growth and migration of murine lung endothelial cells were decreased when cells were treated with CM from sarcoma cells expressing wt p53 compared with CM from sarcoma cells expressing mutant p53. The introduction of wt p53 into sarcoma cells containing mutant p53 significantly reduced the expression of vascular endothelial growth factor (VEGF), which is a key mediator of tumor angiogenesis. Stimulation of endothelial cell migration by CM from cells expressing mutant p53 was significantly reduced after anti-VEGF neutralizing antibody was added to the CM. Using luciferase as the reporter of VEGF promoter activity, we found that wt p53 inhibited VEGF promoter activity in SKLMS-1 cells. Deletion analysis defined an 87-bp region (bp -135 to -48) in the VEGF promoter that is necessary for inhibiting VEGF promoter activity by wt p53. The transcription factor Sp1 may be involved in the repression of VEGF promoter activity by wt p53 in SKLMS-1 cells. These data indicated that wt p53 can suppress angiogenesis in human soft-tissue sarcomas by transcriptional repression of VEGF expression.

The spin correlation coefficent combinations A{sub xx}+A{sub yy} and A{sub xx}-A{sub yy}, the spin correlation coefficients A{sub xz} and A{sub zz}, and the analyzing power were measured for p(vector sign)p(vector sign){yields}d{pi}{sup +} between center-of-mass angles 25 degree sign {

A polarized proton beam with a large longitudinal polarization component of $0.545\ifmmode\pm\else\textpm\fi{}0.005$ (96% of the total polarization) was prepared in a storage ring (IUCF--Cooler). This was achieved by means of spin precession solenoids in two of the six straight sections of the ring. A polarized hydrogen storage cell target internal to the ring was used to measure the longitudinal spin correlation coefficient ${A}_{\mathrm{zz}}$ in $\mathrm{pp}$ elastic scattering over the laboratory angular range $5.5\ifmmode^\circ\else\textdegree\fi{}$--$43.5\ifmmode^\circ\else\textdegree\fi{} ({\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}=11.5\ifmmode^\circ\else\textdegree\fi{}$--$90\ifmmode^\circ\else\textdegree\fi{})$ with statistical errors of typically 0.025. The absolute normalization was determined to an accuracy of 2.0% by use of the identity ${A}_{\mathrm{yy}}\ensuremath{-}{A}_{\mathrm{xx}}\ensuremath{-}{A}_{\mathrm{zz}}\ensuremath{\equiv}1$ at ${\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}=90\ifmmode^\circ\else\textdegree\fi{}.$ The identity also allows a reduction of the scale factor uncertainty of the previously published analyzing powers and spin correlation coefficients. The results are compared to recent $\mathrm{pp}$ partial wave analyses and $\mathrm{NN}$ potential models.

A planned experiment to measure the nuclear polarization of H2 molecules formed by recombination of polarized H atoms is described. Polarization will be measured with a longitudinally polarized 200 MeV proton beam and a longitudinally polarized storage cell gas target at the IUCF cooler ring.

The spin correlation coefficient combinations S≡Axx+Ayy, D≡Axx−Ayy and the analyzing powers Ay(θ) were measured for pp→pnπ+ at beam energies of 325, 350, 375 and 400 MeV. A polarized internal atomic hydrogen target and a stored, polarized proton beam were used. These polarization observables are sensitive to contributions of higher partial waves. A comparison with recent theoretical calculations is provided.