Developing a robust sensor for infrared imaging bolometers.

A new type of large area sensor for infrared imaging bolometers has been developed. It replaces the thin and fragile free-standing metal foils, which typically have been used, with a multi-layer coated sapphire (or diamond) substrate. Sapphire is transparent to mid-infrared wavelengths, is robust against transients, and can be thick enough to even be the vacuum window. The primary radiation absorber is still a thin deposited metal layer, but now it is partially insulated from the supporting sapphire substrate by a black (carbon-based) layer, which also acts as a blackbody remitter. Test results indicate 6× more noise equivalent power density (estimated NEPD = 23 W/m2 at 5 ms camera exposure time, foil temperature decay time 60 ms) for a 2 µm gold-coated sapphire disk compared to estimated NEP = 4 W/m2 at 1.8 ms exposure time, with foil decay time 420 ms, for a nominal 2.5 µm thick platinum-free-standing foil.

Development of a compact bolometer camera concept for investigation of radiation asymmetries at Wendelstein 7-X.

Power exhaust is one of the central challenges in magnetically confined fusion plasmas. Radiative detachment can be employed to reduce particle and heat fluxes to the divertor target, mitigating divertor damage and erosion. However, accomplishing this for a non-axisymmetric machine such as Wendelstein 7-X is a non-trivial task because of the complex role of transport and plasma-wall interaction in a three-dimensional magnetic field topology. We introduce a new bolometer camera design that can be easily installed in multiple toroidal locations and adapted to the required geometry, providing additional spatial coverage. This can be used to locally enhance tomographic capabilities or to resolve spatial variations of the plasma emissivity. By including these non-uniformities in the total radiated power estimate, global power balance measurements can be improved. We model each bolometer camera using ray tracing. We then analyze the forward-modeled detector response to several physically motivated synthetic emission phantoms with respect to its capability to quantify the local average emissivity. The results prove this concept as a promising asset for the investigation of poloidal and toroidal radiated power asymmetries in Wendelstein 7-X. The first CBC prototypes have undergone development and installation for the next experimental campaign.

MOPP/EBV/CAD hybrid chemotherapy with or without limited radiotherapy in advanced or unfavorably presenting Hodgkin's disease: a report from the Italian Lymphoma Study Group.

PURPOSE: We explored the feasibility, toxicity, and preliminary results of a chemotherapy (CT) regimen, mechlorethamine, vincristine, procarbazine, and prednisone (MOPP)/epidoxirubicin, bleomycin, and vinblastine (EBV)/lomustine (CCNU), doxorubicin, and vindesine (CAD), derived through hybridization, shortening, and intensification of a corresponding 10-drug alternating combination CAD/MOPP/doxorubicin, bleomycin, and vinblastine (ABV), effective in treatment of advanced Hodgkin's disease (HD). PATIENTS AND METHODS: Hybridization involved all drugs except CCNU and mechlorethamine, which were administered in alternating cycles; the length of therapy was reduced from nine to six cycles. The average projected drug doses during the six cycles were increased by 42%, with an overall 1.54 dose-intensification; epidoxorubicin was substituted for doxorubicin at equivalent tumoricidal doses. Radiotherapy (RT) was optional and its indications were limited. RESULTS: Eighty assessable patients with previously untreated, advanced or unfavorably presenting HD were treated in nine cooperating institutions between 1988 and 1991. RT was delivered to 22 patients. Remissions were complete (CR) in 75 patients (93%), partial in three (4%), and null in two (3%). The median relative dose-intensity was 0.71 for the overall regimen. Three of five patients who failed to achieve CR, and two of the four who relapsed, received lower relative dose-intensive cycles. Nonhematologic toxicity was acceptable, but there was considerable hematologic toxicity. Fatal gastrointestinal bleeding was seen in one patient. CONCLUSION: Caution is advised due to the short median follow-up period. Nevertheless, in addition to the excellent response rate, (1) the results were reached through abbreviation, intensification, and hybridization of an existing alternating regimen; (2) RT had limited use in this program, which may have contributed to lowering the risk of second tumors; and (3) the results were obtained in a multicenter study (a condition that often impairs results from clinical trials).

Validation of the international prognostic index in working formulation group A low-grade non-Hodgkin's lymphoma: retrospective analysis of 137 patients from the Gruppo Italiano per lo Studio dei Linfomi registry.

BACKGROUND AND OBJECTIVE: The subset of non-follicular non-Hodgkin's lymphoma (NHL) includes patients with varied prognoses, thus suitable for different therapeutic approaches. The International Prognostic Index (IPI), originally proposed for aggressive NHL, has been demonstrated to be of prognostic relevance also in follicular NHL. The main aim of the study was to validate the IPI in this histologic category; in addition, the specific prognostic classification, currently employed in the Gruppo Italiano per lo Studio dei Linfomi (GISL) prospective therapeutic trials and based on different features, more similar to those applied to chronic lymphocytic leukemia, was analyzed. DESIGN AND METHODS: The present series consists of 137 evaluable patients affected by Working Formulation group A NHL out of 256 cases referred to the GISL Registry. The retrospective prognostic study included the evaluation by both univariate and multivariate analyses of overall survival, response to therapy and response duration. The IPI was applied as originally proposed. The GISL definition of indolent and aggressive disease at diagnosis was based on the presence of B symptoms, bulky disease, anemia and thrombocytopenia. RESULTS: The distribution of patients in IPI risk groups was rather unbalanced with 18%, 47%, 28% and 7% of cases classified as low (L), intermediate-low (IL), intermediate-high (IH) and high (H) risk, respectively. The median overall survival was not reached in either L or IL risk groups, and was 84.1 and 7.4 months for IH and H risk groups, respectively (p=0. 0005). A simplified IPI model was designed merging patients in both intermediate risk groups and the statistical difference of survival retained its significance. GISL prognostic stratification was demonstrated to have a significant association with survival, with a median survival of 71.3 months in aggressive disease and a median survival not reached at 152 months in indolent disease. Both the simplified IPI model and the GISL risk definition retained their significance in multivariate analysis for overall survival, while for response to therapy only the simplified IPI model resulted to be of statistical significance. In addition, the GISL prognostic stratification identified patients with different outcomes within the IPI intermediate risk group, with a median survival of 70.2 months for patients with aggressive disease wheras the median survival for those with indolent disease was not reached. Finally, a prognostic score resulting from the integration of the simplified IPI and the GISL system was statistically validated. INTERPRETATION AND CONCLUSIONS: The retrospective analysis of this series demonstrates the validity of the IPI in non-follicular indolent NHL and the usefulness of integrating the IPI parameters with disease specific prognostic variables.