403 research outputs found

    The CUORE Cryostat: A 1-Ton Scale Setup for Bolometric Detectors

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    The cryogenic underground observatory for rare events (CUORE) is a 1-ton scale bolometric experiment whose detector consists of an array of 988 TeO2 crystals arranged in a cylindrical compact structure of 19 towers. This will be the largest bolometric mass ever operated. The experiment will work at a temperature around or below 10 mK. CUORE cryostat consists of a cryogen-free system based on pulse tubes and a custom high power dilution refrigerator, designed to match these specifications. The cryostat has been commissioned in 2014 at the Gran Sasso National Laboratories and reached a record temperature of 6 mK on a cubic meter scale. In this paper, we present results of CUORE commissioning runs. Details on the thermal characteristics and cryogenic performances of the system will be also given.Comment: 7 pages, 2 figures, LTD16 conference proceedin

    Marginal zone lymphomas in children and the young adult population; characterization of genetic aberrations by FISH and RT-PCR

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    Marginal zone lymphomas present rarely in children and young adults as either primary nodal or extranodal disease and have an excellent prognosis. To date, chromosomal aberrations have not been analyzed in the pediatric and young adult population. We undertook a study to analyze genetic alterations in nodal and extranodal marginal zone lymphomas in children and young adults using fluorescence in situ hybridization (FISH) and RT-PCR. These findings were correlated with clinical features at presentation and immunophenotype. Forty-one cases were identified meeting these criteria. The age range was 1.5-29 years old with 49% of the cases <18 years of age. 73% of the marginal zone lymphoma cases showed evidence of light chain restriction by immunohistochemistry or flow cytometry. CD43 was coexpressed in 83%. 85% of the marginal zone lymphoma cases tested showed evidence of immunoglobulin heavy chain gene rearrangement. Fifty-nine percent of the cases were nodal marginal zone lymphomas with a median age at presentation of 16 years and an M/F ratio of 7:1. Twenty-one percent of the nodal marginal zone lymphoma cases contained genetic aberrations. Seventeen percent contained trisomy 18 with one case containing an additional trisomy 3. A translocation of the immunoglobulin heavy chain gene to an unknown partner gene was present in one case. Forty-one percent of the cases were extranodal marginal zone lymphomas with a median age of 24 years and a M/F ratio of 1.4:1. Eighteen percent of the extranodal marginal zone lymphoma cases contained genetic aberrations. The t(14;18) involving the IGH and MALT1 genes was present in one case, tetraploidy was present in one case, and another case contained trisomy 3. Overall the incidence of genetic aberrations in marginal zone lymphomas in the pediatric and young adult population is low, but the aberrations seen are similar to those seen in the adult population

    Importance of extensive staging in patients with mucosa-associated lymphoid tissue (MALT)-type lymphoma

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    Lymphoma of the mucosa-associated lymphoid tissue (MALT) type usually arises in MALT acquired through chronic antigenic stimulation triggered by persistent infection and/or autoimmune processes. Due to specific ligand–receptor interactions between lymphoid cells and high-endothelial venules of MALT, both normal and neoplastic lymphoid cells display a pronounced homing tendency to MALT throughout the body. In the case of neoplastic disease these homing properties may be responsible for lymphoma dissemination among various MALT-sites. According to this concept, we have standardized staging procedures in all patients diagnosed with MALT-type lymphoma. All patients with MALT-type lymphoma underwent standardized staging procedures before treatment. Staging included ophthalmologic examination, otolaryngologic investigation, gastroscopy with multiple biopsies, endosonography of the upper gastrointestinal tract, enteroclysis, colonoscopy, computed tomography of thorax and abdomen and bone marrow biopsy. Biopsy was performed in all lesions suggestive for lymphomatous involvement, and evaluation of all biopsy specimens was performed by a reference pathologist. 35 consecutive patients with histologically verified MALT-type lymphoma were admitted to our department. Twenty-four patients (68%) had primary involvement of the stomach, five (15%) had lymphoma of the ocular adnexa, three (8.5%) had lymphoma of the parotid, and three (8,5%) of the lung. Lymph-node involvement corresponding to stage EII disease was found in 13 patients (37%), only one patient with primary gastric lymphoma had local and supradiaphragmatic lymph-node involvement (stage EIII). Bone marrow biopsies were negative in all patients. Overall, eight of 35 patients (23%) had simultaneous biopsy-proven involvement of two MALT-sites: one patient each had lymphoma of parotid and lacrimal gland, conjunctiva and hypopharynx, conjunctiva and skin, lacrimal gland and lung, stomach and colon, and stomach and lung. The remaining two patients had bilateral parotideal lymphoma. Staging work-up was negative for lymph-node involvement in all of these eight patients. The importance of extensive staging in MALT-type lymphoma is emphasized by the demonstration of multiorgan involvement in almost a quarter of patients. In addition, our data suggest that extra-gastrointestinal MALT-type lymphoma more frequently occurs simultaneously at different anatomic sites than MALT-type lymphoma involving the GI-tract. © 2000 Cancer Research Campaig

    Somatostatin-receptor scintigraphy for staging and follow-up of patients with extraintestinal marginal zone B-cell lymphoma of the mucosa associated lymphoid tissue (MALT)-type

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    The majority of lymphomas of the mucosa-associated lymphoid tissue (MALT)-type arise in the stomach, but extragastric locations are also frequently encountered. Due to previous results indicating that somatostatin receptor (SSTR)-expression distinguishes between gastric and extragastric MALT-type lymphoma, we have initiated a study to evaluate the role of SSTR-scintigraphy for staging and follow-up of patients with extragastric manifestations of MALT-type lymphoma. A total of 30 consecutive patients, including 24 with primary extragastric MALT-type lymphoma, 5 patients with dissemination to extragastric sites (including colon, lung, parotid, ocular adnexa and breast) following an initial gastric MALT-lymphoma and one patient with spread to stomach, lung and lymph nodes following parotid lymphoma were prospectively studied. All patients had histologically verified MALT-type lymphoma: 2 patients had lymphoma presenting in the lung, 9 in the ocular adnexa, 7 had lymphomas in the parotid, 2 patients had disease located in the breast, 3 patients had lymph-node relapse following MALT-type lymphoma of the parotid, the lacrimal gland and the thyroid, and 1 had primary MALT-lymphoma of the liver. All patients underwent SSTR-scintigraphy using 111In-DTPA-D-Phe1-Octreotide (111In-OCT) before initiation of therapy, while 13 also had a second scan after treatment. The results of gamma camera imaging were compared to conventional staging. No positive scans could be obtained in patients with dissemination following gastric lymphoma, while all patients with primary extragastric lymphoma had positive scans at the site of histologically documented involvement before initiation of therapy. In addition, also the patient with secondary spread to stomach, lung and lymph nodes was positive in all documented lymphoma sites. In one patient, focal tracer uptake in projection to the maxillary sinus was documented, which was bioptically verified as inflammation. In the scans performed after therapy, focal tracer accumulation in the left orbit indicated persistance of disease following irradiation in one patient with otherwise negative work-up, which was verified by MRI and biopsy 6 months later. In another patient, a positive scan indicated disease relapse in the lacrimal gland 9 months before clinical verification by means of ultrasound. In one patient, a focus not present in the pretherapeutic scan was found in the ethmoidal sinus, corresponding to a hyperplastic polyp. Both SST-scan as well as CT indicated disease persistance in one case, while negative scans corresponding to complete remission as judged by conventional staging were obtained following therapy in the remaining patients, and absence of relapse has been confirmed for a median follow-up of 2 years. These results indicate that 111In-OCT is an excellent tool for staging and non-invasive therapy-monitoring in extragastric MALT-type lymphomas. These data further confirm our initial finding that gastric MALT-type lymphomas do not express relevant amounts of respective SSTR, and that SSTR-scanning is able to distinguish between gastric vs extragastric origin of MALT-type lymphoma irrespective of the site of presentation.© 2001 Cancer Research Campaign  http://www.bjcancer.co

    The CUORE cryostat: an infrastructure for rare event searches at millikelvin temperatures

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    The CUORE experiment is the world's largest bolometric experiment. The detector consists of an array of 988 TeO2 crystals, for a total mass of 742 kg. CUORE is presently taking data at the Laboratori Nazionali del Gran Sasso, Italy, searching for the neutrinoless double beta decay of 130Te. A large custom cryogen-free cryostat allows reaching and maintaining a base temperature of about 10 mK, required for the optimal operation of the detector. This apparatus has been designed in order to achieve a low noise environment, with minimal contribution to the radioactive background for the experiment. In this paper, we present an overview of the CUORE cryostat, together with a description of all its sub-systems, focusing on the solutions identified to satisfy the stringent requirements. We briefly illustrate the various phases of the cryostat commissioning and highlight the relevant steps and milestones achieved each time. Finally, we describe the successful cooldown of CUORE

    Simulations of events for the LUX-ZEPLIN (LZ) dark matter experiment

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    The LUX-ZEPLIN dark matter search aims to achieve a sensitivity to the WIMP-nucleon spin-independent cross-section down to (1–2)×10−12 pb at a WIMP mass of 40 GeV/c2. This paper describes the simulations framework that, along with radioactivity measurements, was used to support this projection, and also to provide mock data for validating reconstruction and analysis software. Of particular note are the event generators, which allow us to model the background radiation, and the detector response physics used in the production of raw signals, which can be converted into digitized waveforms similar to data from the operational detector. Inclusion of the detector response allows us to process simulated data using the same analysis routines as developed to process the experimental data
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