953 research outputs found
Branching fractions and charge asymmetries in charmless hadronic B decays at BaBar
We present measurements of branching fraction and charge asymmetry in charmless hadronic B decays with η and η mesons in the final state. All
results use the final BaBar dataset corresponding to 465 × 106 BB pairs
Analysis of heavy spin--3/2 baryon--heavy spin--1/2 baryon--light vector meson vertices in QCD
The heavy spin--3/2 baryon--heavy spin--1/2 baryon vertices with light vector
mesons are studied within the light cone QCD sum rules method. These vertices
are parametrized in terms of three coupling constants. These couplings are
calculated for all possible transitions. It is shown that correlation functions
for these transitions are described by only one invariant function for every
Lorenz structure. The obtained relations between the correlation functions of
the different transitions are structure independent while explicit expressions
of invariant functions depend on the Lorenz structure.Comment: 17 Pages, 6 Figures and 4 Table
Comparison Between Diffusion-Weighted MRI and I-123-mIBG Uptake in Primary High-Risk Neuroblastoma
Background: High-risk neuroblastoma (HR-NB) has a variable response to preoperative chemotherapy. It is not possible to
differentiate viable vs. nonviable residual tumor before surgery.
Purpose: To explore the association between apparent diffusion coefficient (ADC) values from diffusion-weighted magnetic resonance imaging (DW-MRI), 123I-meta-iodobenzyl-guanidine (123I-mIBG) uptake, and histology before and after
chemotherapy.
Study Type: Retrospective.
Subjects: Forty patients with HR-NB.
Field Strength/Sequence: 1.5T axial DW-MRI (b = 0,1000 s/mm2
) and T2-weighted sequences. 123I-mIBG scintigraphy planar imaging (all patients), with additional 123I-mIBG single-photon emission computed tomography / computerized tomography (SPECT/CT) imaging (15 patients).
Assessment: ADC maps and 123I-mIBG SPECT/CT images were coregistered to the T2-weighted images. 123I-mIBG uptake
was normalized with a tumor-to-liver count ratio (TLCR). Regions of interest (ROIs) for primary tumor volume and different
intratumor subregions were drawn. The lower quartile ADC value (ADC25prc) was used over the entire tumor volume and
the overall level of 123I-mIBG uptake was graded into avidity groups.
Statistical Tests: Analysis of variance (ANOVA) and linear regression were used to compare ADC and MIBG values before
and after treatment. Threshold values to classify tumors as viable/necrotic were obtained using ROC analysis of ADC and
TLCR values.
Results: No significant difference in whole-tumor ADC25prc values were found between different 123I-mIBG avidity groups
pre- (P = 0.31) or postchemotherapy (P = 0.35). In the “intratumor” analysis, 5/15 patients (prechemotherapy) and 0/14
patients (postchemotherapy) showed a significant correlation between ADC and TLCR values (P < 0.05). Increased tumor
shrinkage was associated with lower pretreatment tumor ADC25prc values (P < 0.001); no association was found with pretreatment 123I-mIBG avidity (P = 0.17). Completely nonviable tumors had significantly lower postchemotherapy ADC25prc
values than tumors with >10% viable tumor (P < 0.05). Both pre- and posttreatment TLCR values were significantly higher
in patients with >50% viable tumor than those with 10–50% viable tumor (P < 0.05).
Data Conclusion: 123I-mIBG avidity and ADC values are complementary noninvasive biomarkers of therapeutic response in
HR-NB.
Level of Evidence: 4.
Technical Efficacy Stage: 3
The Future of Neutrino Mass Measurements: Terrestrial, Astrophysical, and Cosmological Measurements in the Next Decade. Highlights of the NuMass 2013 Workshop. Milano, Italy, February 4 - 7, 2013
The third Workshop of the NuMass series ("The Future of Neutrino Mass
Measurements: Terrestrial, Astrophysical, and Cosmological Measurements in the
Next Decade: NuMass 2013") was held at Dipartimento di Fisica "G. Occhialini,
University of Milano-Bicocca in Milano, Italy, on 4-7 February 2013. The goal
of this international workshop was to review the status and future of direct
and indirect neutrino mass measurements in the laboratory as well as from
astrophysical and cosmological observations. This paper collects most of the
contributions presented during the Workshop
Response of a TeO_2 bolometer to alpha particles
crystals are used as bolometers in experiments searching for Double
Beta Decay without emission of neutrinos. One of the most important issues in
this extremely delicate kind of experiments is the characterization of the
background. The knowledge of the response to particles in the energy
range where the signal is expected is therefore a must. In this paper we report
the results on the response function of a bolometer to 's
emitted by Sm dissolved in the crystal at the growth phase. A Quenching
Factor of () is found, independent of the temperature in the
investigated range. The energy resolution on peaks shows a standard
calorimeter energy dependence: . Signal pulses show no difference between
and particle
The CUORE Cryostat: A 1-Ton Scale Setup for Bolometric Detectors
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
Variation in Glycemic Outcomes in Focal Forms of Congenital Hyperinsulinism - The UK Perspective
Context: In focal congenital hyperinsulinism (CHI), localized clonal expansion of pancreatic β-cells causes excess insulin secretion and severe hypoglycemia. Surgery is curative, but not all lesions are amenable to surgery. Objective: We describe surgical and nonsurgical outcomes of focal CHI in a national cohort. Methods: Patients with focal CHI were retrospectively reviewed at 2 specialist centers, 2003-2018. Results: Of 59 patients with focal CHI, 57 had heterozygous mutations in ABCC8/KCNJ11 (51 paternally inherited, 6 de novo). Fluorine-18 L-3,4 dihydroxyphenylalanine positron emission tomography computed tomography scan identified focal lesions in 51 patients. In 5 patients, imaging was inconclusive; the diagnosis was established by frozen section histopathology in 3 patients, a lesion was not identified in 1 patient, and 1 declined surgery. Most patients (n = 56) were unresponsive to diazoxide, of whom 33 were unresponsive or partially responsive to somatostatin receptor analog (SSRA) therapy. Fifty-five patients underwent surgery: 40 had immediate resolution of CHI, 10 had persistent hypoglycemia and a focus was not identified on biopsy in 5. In the 10 patients with persistent hypoglycemia, 7 underwent further surgery with resolution in 4 and ongoing hypoglycemia requiring SSRA in 3. Nine (15% of cohort) patients (1 complex surgical access; 4 biopsy negative; 4 declined surgery) were managed conservatively; medication was discontinued in 8 children at a median (range) age 2.4 (1.5-7.7) years and 1 remains on SSRA at 16 years with improved fasting tolerance and reduction in SSRA dose. Conclusion: Despite a unifying genetic basis of disease, we report inherent heterogeneity in focal CHI patients impacting outcomes of both surgical and medical management
CUPID-0: the first array of enriched scintillating bolometers for 0decay investigations
The CUPID-0 detector hosted at the Laboratori Nazionali del Gran Sasso, Italy, is the first large array of enriched scintillating cryogenic detectors for the investigation of82Se neutrinoless double-beta decay (0). CUPID-0 aims at measuring a background index in the region of interest (RoI) for 0at the level of 10- 3 counts/(keV kg years), the lowest value ever measured using cryogenic detectors. CUPID-0 operates an array of Zn82Se scintillating bolometers coupled with bolometric light detectors, with a state of the art technology for background suppression and thorough protocols and procedures for the detector preparation and construction. In this paper, the different phases of the detector design and construction will be presented, from the material selection (for the absorber production) to the new and innovative detector structure. The successful construction of the detector lead to promising preliminary detector performance which is discussed here
First array of enriched ZnSe bolometers to search for double beta decay
The R&D activity performed during the last years proved the potential of ZnSe
scintillating bolometers to the search for neutrino-less double beta decay,
motivating the realization of the first large-mass experiment based on this
technology: CUPID-0. The isotopic enrichment in Se, the ZnSe
crystals growth, as well as the light detectors production have been
accomplished, and the experiment is now in construction at Laboratori Nazionali
del Gran Sasso (Italy). In this paper we present the results obtained testing
the first three ZnSe crystals operated as scintillating bolometers, and
we prove that their performance in terms of energy resolution, background
rejection capability and intrinsic radio-purity complies with the requirements
of CUPID-0
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