1,197 research outputs found
The 4 K outer cryostat for the CUORE experiment: construction and quality control
The external shell of the CUORE cryostat is a large cryogen-free system
designed to host the dilution refrigerator and the bolometers of the CUORE
experiment in a low radioactivity environment. The three vessels that form the
outer shell were produced and delivered to the Gran Sasso underground
Laboratories in July 2012. In this paper, we describe the production techniques
and the validation tests done at the production site in 2012.Comment: 11 pages, 13 figures; to appear in NIM
Characterization of Lactococcus strains isolated from artisanal Oaxaca cheese
Lactococci strains obtained from raw-milk Oaxaca cheese through its production process in two factories from the Tulancingo Valley, Mexico, were isolated and characterized. A total of 120 colonies were selected from the growth in M17 and MRS agars. Twenty were identified as lactococci strains, all Lactococcus lactis, and were characterized by molecular and phenotypic methods including carbohydrate use, enzymatic profile, acidifying capacity, and antibiotic and phage resistance. High phenotypic diversity was observed and confirmed among the Lactococcus lactis strains by rep-PCR fingerprints. Fifty percent of the strains were resistant to streptomycin and 35% to erythromycin. Nine isolates were considered as fast acidifying strains. The predominant volatile compounds produced were 3-methylbutanol, 3-methylbutanal and butane-2,3-dione. A selection of strains isolated in this study has shown satisfactory characteristics to be used as potential starters for the industrial production of Oaxaca cheese.Peer reviewe
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
The CUORE cryostat: an infrastructure for rare event searches at millikelvin temperatures
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
Nursing Care of Patients With Cirrhosis: The LiverHope Nursing Project
Cirrhosis is a complex disease that is associated with disturbances in different organs besides the liver, including kidneys, heart, arterial circulation, lungs, gut, and brain. As a consequence, patients develop a number of complications that result in frequent hospital admissions and high morbidity and mortality. Patients with cirrhosis require constant and rigorous monitoring both in and outside the hospital. In this context, the role of nurses in the care of patients with cirrhosis has not been sufficiently emphasized and there is very limited information about nursing care of patients with cirrhosis compared with other chronic diseases. The current article provides a review of nursing care for the different complications of patients with cirrhosis. Nurses with specific knowledge on liver diseases should be incorporated into multidisciplinary teams managing patients with cirrhosis, both inpatient and outpatient. Conclusion: Nurses play an important role in the management and prevention of complications of the disease and improvement in patients’ quality of life and bridge the gap between clinicians and families, between primary care and hospital care, and provide medical education to patients and caregivers
Validation of techniques to mitigate copper surface contamination in CUORE
In this article we describe the background challenges for the CUORE
experiment posed by surface contamination of inert detector materials such as
copper, and present three techniques explored to mitigate these backgrounds.
Using data from a dedicated test apparatus constructed to validate and compare
these techniques we demonstrate that copper surface contamination levels better
than 10E-07 - 10E-08 Bq/cm2 are achieved for 238U and 232Th. If these levels
are reproduced in the final CUORE apparatus the projected 90% C.L. upper limit
on the number of background counts in the region of interest is 0.02-0.03
counts/keV/kg/y depending on the adopted mitigation technique.Comment: 10 pages, 6 figures, 6 table
Search for 14.4 keV solar axions from M1 transition of Fe-57 with CUORE crystals
We report the results of a search for axions from the 14.4 keV M1 transition
from Fe-57 in the core of the sun using the axio-electric effect in TeO2
bolometers. The detectors are 5x5x5 cm3 crystals operated at about 10 mK in a
facility used to test bolometers for the CUORE experiment at the Laboratori
Nazionali del Gran Sasso in Italy. An analysis of 43.65 kg d of data was made
using a newly developed low energy trigger which was optimized to reduce the
detectors energy threshold. An upper limit of 0.63 c kg-1 d-1 was established
at 95% C.L.. From this value, a lower bound at 95% C.L. was placed on the
Peccei-Quinn energy scale of fa >= 0.76 10**6 GeV for a value of S=0.55 for the
flavor-singlet axial vector matrix element. Bounds are given for the interval
0.15 < S < 0.55.Comment: 14 pages, 6 figures, submitted to JCA
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