Large-angle scattering and quasi-elastic barrier distributions

We study in detail the barrier distributions extracted from large-angle quasi-elastic scattering of heavy ions at energies near the Coulomb barrier. Using a closed-form expression for scattering from a single barrier, we compare the quasi-elastic barrier distribution with the corresponding test function for fusion. We examine the isocentrifugal approximation in coupled-channels calculations of quasi-elastic scattering and find that for backward angles, it works well, justifying the concept of a barrier distribution for scattering processes. This method offers an interesting tool for investigating unstable nuclei. We illustrate this for the $^{32}$Mg + $^{208}$Pb reaction, where the quadrupole collectivity of the neutron-rich $^{32}$Mg remains to be clarified experimentally.Comment: 26 pages, 10 eps figure

Role of non-collective excitations in heavy-ion fusion reactions and quasi-elastic scattering around the Coulomb barrier

Despite the supposed simplicity of double-closed shell nuclei, conventional coupled-channels calculations, that include all of the known collective states of the target and projectile, give a poor fit to the fusion cross section for the $^{16}$O + $^{208}$Pb system. The discrepancies are highlighted through the experimental barrier distribution and logarithmic derivative, that are both well defined by the precise experimental fusion data available. In order to broaden our search for possible causes for this anomaly, we revisit this system and include in our calculations a large number of non-collective states of the target, whose spin, parity, excitation energy and deformation paramter are known from high-precision proton inelastic-scattering measurements. Although the new coupled-channels calculations modify the barrier distribution, the disagreemnt with experiment remains both for fusion and for quasi-elastic (QE) scattering. We find that the Q-value distributions for large-angle QE scattering become rapidly more important as the incident energy increases, reflecting the trend of the experimental data. The mass-number dependence of the non-collective excitations is discussed.Comment: 8 pages, 7 figure

Combined chemotherapy in 76 children with non-Hodgkin's lymphoma excluding Burkitt's lymphoma.

From January 1983 to December 1986 seventy-six previously untreated children with non-Hodgkin's lymphoma (NHL) were treated by combination chemotherapy. Burkitt's lymphoma patients were ineligible. The treatment regimens include intermittent chemotherapy and for non-localized patients, prophylactic central nervous system chemotherapy. Intrathoracic non-Hodgkin's lymphoma patients also had cranial prophylactic radiotherapy. Sixty-six patients (86.8%) achieved complete remission. Two year failure-free survival rate was 82.1% for localized (stage I and II) NHL and 53.3% for non-localized (stage III and IV) NHL patients. Failure-free survival did not differ significantly for the two major histologic diagnoses, but two year survival rate was lower in diffuse poorly differentiated lymphoblastic than undifferentiated non-Burkitt's lymphoma (50% versus 66.8% respectively). Failure-free survival rate was 53.7% in mediastinal disease and, 73.2% in abdominal disease at 24 months. Relapse rate was higher in mediastinal cases (46.1%) than primary abdominal cases (24.3%) at 24 months. Eleven (13.5%) died of treatment related sepsis. Although the overall survival rate was 72.4% at 2 years we need novel or more intensive programmes for mediastinal and non-localized disease

Intramuscular and intratendinous placenta‐derived mesenchymal stromal‐like cell treatment of a chronic quadriceps tendon rupture

Background: Quadriceps tendon ruptures (QTRs) are rare but debilitating injuries, often associated with chronic metabolic conditions or long-term steroid treatment. While the surgical treatment for acute QTRs is described thoroughly, no common strategy exists for the often frustrating treatment of chronic, reoccurring QTRs. The pro-angiogenic and immunomodulatory properties of placenta-derived adherent mesenchymal stromal-like (PLX-PAD) cells have been described to protect musculoskeletal tissues from inflammation and catabolic cytokine migration, yet little is known about the regenerative potential of PLX-PAD cells in repetitively damaged tendon tissue. Case: We report the case of an 80-year-old male patient with a chronic three-time QTR of his right knee. The quadriceps tendon was reconstructed applying a conventional suture anchor repair procedure combined with a synthetic mesh augmentation and additional intramuscular and intratendineous PLX-PAD cell injections as an individualized treatment approach. No adverse events were reported, and excellent radiological and functional outcomes with a passive range of motion of 0/0/120 degrees knee extension-flexion were observed at the 12 month follow-up. Gait analysis confirmed restoration of joint motion, including gait speed, deficit in step length, and knee extensor muscle strength (pre-surgery: 0.98 m/s, 40 cm, 42.4 +/- 12.4 N; 9 months post-surgery: 1.07 m/s, 0 cm, 10.4 +/- 18.9 N) as well as hyperextension throughout stance and late swing phases (pre-surgery: -11.2 +/- 0.9 degrees; 9 months post-surgery: -2.7 +/- 1.6 degrees). Postoperative lymphocyte and cytokine analyses from the patient's peripheral blood serum suggested a systemic short-term immunoregulatory reaction with postoperatively increased interleukin (IL)-6 (pre-surgery: 0.79 pg/mL; day 1: 139.97 pg/mL; day 5: 5.58 pg/mL; 9 months: 1.76 pg/mL) and IL-10 (pre-surgery: 0.9 pg/mL; day 1: 1.21 pg/ mL; day 5: 0.3 pg/mL; 9 months: 0.34 pg/mL) levels that decreased again over time. Conclusions: Herein, we demonstrate a successfully treated chronic QTR with a synergistic surgical and biological reconstructive treatment approach. This local add-on treatment with PLX-PAD cells may be considered in specific cases of chronic QTRs, not susceptible to traditional suture anchor procedures and which exhibit a high risk of treatment failure. Further scientific engagement is warranted to explore underlying immunomodulatory mechanisms of action behind PLX-PAD cell treatment for tendon injuries

China and the crisis : global power, domestic caution and local initiative

Even though the global crisis had a quick and dramatic impact on Chinese exports, the Chinese government responded with a range of policy responses that have helped maintain high rates of growth. This success has helped propel China to the centre of global politics, accelerating what many perceive to be a power shift from the West to China. But these gains were achieved by reversing policy in previous years designed to make a fundamental shift in China‟s mode of development, and have highlighted the problems associated with making such a transition. At the moment that many are looking at the Chinese "model" as a potential alternative to the Washington Consensus, one of the consequences of the crisis is to further question the long term efficacy of this "model" in China itself