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The slow component of the output pulse of Semi-Insulating (SI) Gallium Arsenide (GaAs) particle detectors, which affects charge collection efficiency (cce), has been generally attributed to trapping/detrapping effects. However, most of the detectors analyzed in the literature can only be operated below the voltage V/sub d/ necessary to extend the electric field all the way to the ohmic contact, making difficult to distinguish between the effect of the non-active part of the detector and that of trapping/detrapping. To do that, we have carefully analyzed the output signals of SI GaAs detectors, operated below and above V/sub d/ and irradiated with /sup 241/Am /spl alpha/ particles. When the detector is biased below V/sub d/ the output signals are affected also by the non-active part of the detector itself, while, when the detector is operated above V/sub d/, the output signals are only affected by trapping/detrapping of charge carriers. We found that trapping/detrapping is only relevant for the hole contribution to the signal. Trapping/detrapping effects are in agreement with the characteristics of deep levels present in the detectors as analyzed by means of PICTS (Photo Induced Current Transient Spectroscopy) and P-DLTS (Photo Deep Level Transient Spectroscopy).

Observations have been made of the behaviour of high resistivity silicon and semi-insulating gallium arsenide ionizing radiation detectors after exposure of up to 30 Mrad 60 Co photons. Results are presented on leakage current and deep level defects of the substrate material of photon damage devices. These findings have been related to the charge collection efficiency of the detectors.

In recent papers, we have investigated, within the context of the RD-8 experiment, the behaviour as a function of bias of the active region of particle detectors made by Alenia SpA on semi-insulating liquid encapsulated Czochralski gallium arsenide: the active region width depends linearly on the bias voltage. The diodes were found to break down as soon as the field reached the back ohmic contact. This suggested that the ohmic contact was injecting holes into the diode, therefore we have decided to develop a new, non-injecting, non-alloyed ohmic contact. This new contact allows us to go far beyond, five times, the voltage bias necessary to have a fully active detector. The higher voltage reached by the detectors helps us improve the charge collection efficiency, up to more than 95% for alphas and more than 90% for beta (mips) particles and X-rays, giving a more stable operation of the detectors. For the first time we can explore the characteristics of a GaAs detector beyond the voltage needed for it to be completely active.

In a recent paper, it was described how semi-insulating (SI) liquid encapsulated Czochralski (LEC) gallium arsenide particle detectors made by Alenia SpA have been tested and found to be understandable in terms of one function: the local charge collection efficiency. We have now measured, always within the context of the RD8 experiment, the local charge collection efficiency for these diodes using a technique called OBIC (optical beam induced current) and derived the active region width ( W ) as a function of bias in a range of values lower than those obtainable with particles. Using data both from OBIC and from the previous paper, W is found to behave approximately linearly as a function of bias larger than about 50 V. Below this value, W follows a square root law as a function of bias.

The objective of this research is to understand the nature and diffusion of antisemitism and Islamophobia in Italy. It is based on 1528 interviews among a representative sample of the Italian population stratified according to age, gender, and residence. The questionnaire used was built by a set of different scales: antisemitic, Islamophobic, and three others scales to take into account authoritarian, ethnocentric, and anomic attitudes. To test assumptions regarding the impact of these predictors of antisemitic and Islamophobic prejudice, it was decided to adopt the statistical technique of path analysis. Outcomes of our research draw attention on the distribution of antisemitism and Islamophobia among Italian people, their nature as a combination of old and new prejudices, and their linking with broader sets of attitudes such as anomie, ethnocentrism, and authoritarianism.

6629 Background: The FCR regimen (fludarabine, cyclophosphamide, rituximab) significantly improves the outcome of patients (pts) with chronic lymphocytic leukemia (CLL). However, myelotoxicity and immunosuppression are a limitation to the use of this regimen in elderly patients and in those with co-morbidities. The combination of rituximab (R) with chlorambucil (CLB; R-CLB) is an attractive therapeutic option for this subset of patients considering the expected good tolerability and potentially increased activity of this schedule. This study was designed to determine whether the R-CLB combination is a feasible and beneficial first-line treatment for elderly patients with CLL and to define the role of maintenance with R. Methods: 97 elderly patients requiring first-line therapy received CLB (8 mg/m²/day p.o., d1-d7, courses 1-8) and R (375 mg/m², course 3 and 500 mg/m², courses 4-8) every 28 days. Responsive patients were subsequently randomized to receive R maintenance (375 mg/m² every 2 months for 2 year...

Il lavoro svolto ha consentito di acquisire dati sull'attuale livello di autonomia dei bambini italiani. Dai dati emerge che la mobilità autonoma dei bambini aumenta con l'età con un significativo incremento in corrispondenza del passaggio dalla scuola primaria alla secondaria (11 anni). Inoltre emerge che bambini e ragazzi tendono a sovrastimare la loro autonomia mentre i genitori tendono a sottostimarla.

Abstract 294 Rituximab plus fludarabine/cyclophosphamide (R-FC) is currently the standard of care for fit patients with untreated or relapsed CLL. However, patients with CLL are predominantly an elderly population and many of these patients may have comorbidities that make them less suitable to receive fludarabine-containing therapy. Chlorambucil-based treatments are frequently used for these patients despite the fact that clinical benefits are limited. There is a need for well-tolerated and more efficacious treatment regimens for these patients. The ML21445 study evaluated the combination of rituximab and chlorambucil (R-chlorambucil) as first-line treatment for patients with CLL considered ineligible for treatment with the current standard of care, R-FC. Patients aged >65 years (or 60–65 years and ineligible for fludarabine) were treated with eight 28-day cycles of chlorambucil (8 mg/m2/day Days 1–7) with rituximab administered on Day 1 of cycle 3 (375 mg/m2) and cycles 4–8 (500 mg/m2). Patients with a response at the end of induction were randomized to rituximab maintenance therapy (375 mg/m2 every 8 weeks for 2 years) or observation. The induction phase of the study is complete while the maintenance phase is still ongoing. The overall response rate (ORR) in 85 patients who received at least one dose of rituximab during induction was 81.2% (n = 69) with 16.5% (n = 14) achieving a complete response (CR) and 2.4% (n = 2) a CR with incomplete bone marrow recovery (CRi). ORR and CR rates were similar across the different Binet stages (ORR: Binet A 86.4%, Binet B 79.6%, Binet C 78.6%) and age categories (ORR: 60–64 years 84.6%, 65–69 years 85.2%, 70–74 years 75.0%, ≥75 years 81.0%). Two of four patients aged ≥80 years responded to induction treatment. Logistic regression analysis revealed no correlation between known biological prognostic factors – CD38, cytogenetics, IGHV mutational status, ZAP-70, thymidine kinase, soluble CD23, and beta-2 microglobulin – and response to treatment. To further investigate possible factors influencing response, pre-treatment patterns of gene expression were analyzed in different patient subgroups. Material was available for 62 patients, including 16 with CR/CRi, 41 partial responders and 5 non-responders. In an exploratory analysis, mRNA expression was examined using Affymetrix® Human Genome U133 microarrays. This revealed marked differences in pre-treatment gene expression profiles between response groups. Non-responders showed a homogeneous gene expression signature involving up-modulation of transcripts involved in anti-apoptotic and pro-proliferative pathways, including K-ras and N-ras. CR/CRi patients also showed a homogeneous pattern of gene expression that was clearly distinct from non-responding patients, while patients with a partial response showed a more heterogeneous pattern of gene expression before treatment. These initial findings reflect the heterogeneity of CLL and suggest that microarray analysis of gene expression may be useful in predicting response to R-chlorambucil in elderly patients with CLL. Disclosures: Foa: Roche: Consultancy, Speakers Bureau. Cuneo:Roche: Consultancy, Speakers Bureau. Montillo:Roche: Membership on an entity's Board of Directors or advisory committees. Alietti:Roche: Employment. Runggaldier:Roche: Employment. Gamba:Roche Italia: Employment.

VAD, (Vincristine, Doxorubicin and Dexamethasone) was initially proposed as a salvage therapy for myeloma patients in whom prior alkylating agent therapy failed, although in recent years VAD has been surpassed by novel combination therapies with new biological agents such as thalidomide (and its derivative, lenalidomide) and bortezomib. After the excellent results obtained by the novel agents, VAD can no longer be proposed in preparation to autologous transplantation, although there are still indications that VAD remains useful and clinically relevant in the initial treatment of symptomatic multiple myeloma.

This study was an evaluation of the psychomotor profiles of 22 schizophrenic patients, investigated by means of a test battery developed for the assessment of psychomotor profiles of 10- to 12-year-old children. Analysis indicates chat abnormal psychomotor development is an inherent feature of the disease and probably is antecedent to a full psychopathological picture.

Aims. Diffuse large B-cell lymphomas (DLBCL) can be divided into different subgroups (germinal center B-cell-like [GCB] and non-GCB) according to their gene expression profiles. Immunohistochemistry has been proposed as a surrogate for identifying these subgroups, but data about its efficacy in providing prognostic information are conflicting. Methods and results. This study retrospectively analyzed a series of 105 DLBCL, defined as GCB and non-GCB according to CD10, bcl-6, and MUM1 expression. All patients received a first-line anthracycline-based (CHOP-like) chemotherapy. A total of 50 patients (48%) were identified as GCB and 55 (52%) as non-GCB. The overall response rate was 89% (94/105), with 62 (59%) complete response. Disease progressions were equally distributed between the 2 subgroups and were not significantly different ( P = .756) considering the primary site of involvement (nodal or extranodal). The median follow-up was 62 months (range 5-126 months). Overall survival at 5 years was not significantly different between the groups ( P = .3468) and was 72.3% and 66.6% for GCB and non-GCB, respectively. Conclusion. The results do not support the prognostic value of GCB and non-GCB immunohistochemical categories in DLBCL of both nodal and extranodal origin. Furthermore, a limited number of antigens may be not sufficient to identify the same patterns defined by cDNA microarray. Prospective studies are warranted to address this issue.

Summary Background The aim of this study was to assess clinicopathological characteristics and outcome in a series of primary ocular adnexal lymphomas (POALs). Patients and methods Nineteen patients with localised (stage IE) POAL were followed for a median of 96 months (24–156). The diagnosis was based on surgical biopsies followed by immunohistochemistry in 16 cases or fine-needle aspiration followed by immunocytophenotypic analysis in three cases. Twelve patients were treated with local radiotherapy (RT), five with chemotherapy (CT), and two refused further therapy after apparently radical tumour removal achieved by the diagnostic excisional biopsy. Results The histological and immunological pattern was consistent with a diagnosis of MALT-type lymphoma (11 cases), follicular center non-Hodgkin’s lymphoma (three cases), a large-cell variant of Burkitt’s lymphoma (one case), and large-cell transformed MALT lymphoma (one case). Low-grade lymphoma was diagnosed in the three cases which underwent fine-needle aspiration biopsy. All of the patients achieved and maintained complete remission except for those treated with surgical excision alone (two MALT conjunctival lymphoma cases): one of these relapsed locally, the other experienced the systemic spread of a transformed diffuse large-cell lymphoma and died 72 months after diagnosis. The side effects consisted of two cases of RT-related cataract after 52 and 72 months. Conclusions Regardless of histology, prognosis was excellent when surgery plus RT was adopted, and CT seems to be a valid alternative to RT. Surgery alone may be sub-optimal.

We report on the performance and limitations of a 7 mm2, 100 μm thick SI LEC GaAs detector, operated in overdepleted conditions with applied bias of 400 V at 20°C and −30°C, in detecting X- and γ-rays. At 20°C performance is limited to a charge collection efficiency of 92% and to an energy resolution of about 16.8 keV FWHM on the 59.5 keV line of 241Am. At −30°C the charge collection efficiency is 85% and a resolution in between 1.8 and 2.2 keV FWHM in the photon energy range 8–60 keV has been achieved. The latest data represent to our knowledge the best ones yet reported for GaAs LEC detectors.