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1.
Phys Rev Lett ; 115(23): 231802, 2015 Dec 04.
Article in English | MEDLINE | ID: mdl-26684111

ABSTRACT

Borexino is a liquid scintillation detector located deep underground at the Laboratori Nazionali del Gran Sasso (LNGS, Italy). Thanks to the unmatched radio purity of the scintillator, and to the well understood detector response at low energy, a new limit on the stability of the electron for decay into a neutrino and a single monoenergetic photon was obtained. This new bound, τ≥6.6×10^{28} yr at 90% C.L., is 2 orders of magnitude better than the previous limit.

2.
Rev Sci Instrum ; 85(4): 043101, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24784587

ABSTRACT

The high-resolution von Hamos bent crystal spectrometer of the University of Fribourg was upgraded with a focused X-ray beam source with the aim of performing micro-sized X-ray fluorescence (XRF) measurements in the laboratory. The focused X-ray beam source integrates a collimating optics mounted on a low-power micro-spot X-ray tube and a focusing polycapillary half-lens placed in front of the sample. The performances of the setup were probed in terms of spatial and energy resolution. In particular, the fluorescence intensity and energy resolution of the von Hamos spectrometer equipped with the novel micro-focused X-ray source and a standard high-power water-cooled X-ray tube were compared. The XRF analysis capability of the new setup was assessed by measuring the dopant distribution within the core of Er-doped SiO2 optical fibers.


Subject(s)
Spectrometry, X-Ray Emission/instrumentation , Spectrometry, X-Ray Emission/methods , X-Rays
3.
J Environ Radioact ; 138: 444-6, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24725806

ABSTRACT

The decays of (214)Po into (210)Pb and of (212)Po into (208)Pb tagged by the previous decays from (214)Bi and (212)Bi have been studied inserting quartz vials inside the Counting Test Facility (CTF) at the underground laboratory in Gran Sasso (LNGS). We find that the mean lifetime of (214)Po is (236.00 ± 0.42(stat) ± 0.15(syst)) µs and that of (212)Po is (425.1 ± 0.9(stat) ± 1.2(syst)) ns. Our results are compatible with previous measurements, have a much better signal to background ratio, and reduce the overall uncertainties.


Subject(s)
Lead Radioisotopes/analysis , Polonium/analysis , Radioactive Pollutants/analysis , Alpha Particles , Half-Life , Laboratories , Radiation Monitoring
4.
Anim Genet ; 44(3): 305-10, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23134432

ABSTRACT

Although variation in the KIT gene is a common cause of white spotting among domesticated animals, KIT has not been implicated in the diverse white spotting observed in the dog. Here, we show that a loss-of-function mutation in KIT recapitulates the coat color phenotypes observed in other species. A spontaneous white spotting observed in a pedigree of German Shepherd dogs was mapped by linkage analysis to a single locus on CFA13 containing KIT (pairwise LOD = 15). DNA sequence analysis identified a novel 1-bp insertion in the second exon that co-segregated with the phenotype. The expected frameshift and resulting premature stop codons predicted a severely truncated c-Kit receptor with presumably abolished activity. No dogs homozygous for the mutation were recovered from multiple intercrosses (P = 0.01), suggesting the mutation is recessively embryonic lethal. These observations are consistent with the effects of null alleles of KIT in other species.


Subject(s)
Dogs/genetics , Frameshift Mutation , Hair Color/genetics , Proto-Oncogene Proteins c-kit/genetics , Animals , Chromosome Mapping , Computational Biology , Female , Genetic Linkage , Genetic Pleiotropy , Genetic Variation , Genotype , Homozygote , Pedigree , Sequence Analysis, DNA
5.
Acta Anaesthesiol Scand ; 56(9): 1152-5, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22897671

ABSTRACT

BACKGROUND: Models for ultrasound-guided regional anaesthesia (USGRA) are important for research and training. However, the limited data available show great differences in quality of needle and tissue visualisation with regard to the applied model. This study aims to compare common USGRA models and human tissue with regard to their influence on needle visibility. METHODS: We conducted this study using four models (embalmed human cadaver, turkey breast, pork, and synthetic gel models) and a volunteer (human control) as well as two different needles [Stimuplex A (StA), conventional needle; Stimuplex D Plus (StD+), needle with improved echogenicity]. We obtained ultrasound videos of needle advancement and withdrawal using the in-plane approach at a 45° angle in all four models and the volunteer. Fifteen test persons were prospectively enrolled. Ultrasound videos were presented in a randomised, blinded manner. The test persons were asked to rate the visibility of the needle shaft (VS) and tip (VT) on a four-point scale (0-3). RESULTS: VS and VT were comparable between the human control and cadaver model for both needle types. The pork, turkey, and synthetic gel models had significantly higher visibility scores than the human control for both needle types. VS of StD+ was significantly higher than that of StA in the pork and turkey models, but not in the synthetic model, cadaver model, or human control. CONCLUSION: In this pilot study, needle visibility in embalmed cadaver is comparable with that in human control. Needle visibility was significantly higher in other tissue models (turkey breast, pork, synthetic gel models) than in the human control, which may limit their value in training environments.


Subject(s)
Anesthesia, Conduction/methods , Needles , Ultrasonography, Interventional/methods , Anesthesia, Conduction/instrumentation , Animals , Cadaver , Gels , Humans , Meat , Models, Anatomic , Pilot Projects , Sample Size , Swine , Turkeys , Video Recording
6.
Phys Rev Lett ; 108(5): 051302, 2012 Feb 03.
Article in English | MEDLINE | ID: mdl-22400925

ABSTRACT

We observed, for the first time, solar neutrinos in the 1.0-1.5 MeV energy range. We determined the rate of pep solar neutrino interactions in Borexino to be 3.1±0.6{stat}±0.3{syst} counts/(day·100 ton). Assuming the pep neutrino flux predicted by the standard solar model, we obtained a constraint on the CNO solar neutrino interaction rate of <7.9 counts/(day·100 ton) (95% C.L.). The absence of the solar neutrino signal is disfavored at 99.97% C.L., while the absence of the pep signal is disfavored at 98% C.L. The necessary sensitivity was achieved by adopting data analysis techniques for the rejection of cosmogenic {11}C, the dominant background in the 1-2 MeV region. Assuming the Mikheyev-Smirnov-Wolfenstein large mixing angle solution to solar neutrino oscillations, these values correspond to solar neutrino fluxes of (1.6±0.3)×10{8} cm{-2} s^{-1} and <7.7×10{8} cm{-2} s{-1} (95% C.L.), respectively, in agreement with both the high and low metallicity standard solar models. These results represent the first direct evidence of the pep neutrino signal and the strongest constraint of the CNO solar neutrino flux to date.

7.
Phys Rev Lett ; 107(14): 141302, 2011 Sep 30.
Article in English | MEDLINE | ID: mdl-22107184

ABSTRACT

The rate of neutrino-electron elastic scattering interactions from 862 keV (7)Be solar neutrinos in Borexino is determined to be 46.0±1.5(stat)(-1.6)(+1.5)(syst) counts/(day·100 ton). This corresponds to a ν(e)-equivalent (7)Be solar neutrino flux of (3.10±0.15)×10(9) cm(-2) s(-1) and, under the assumption of ν(e) transition to other active neutrino flavours, yields an electron neutrino survival probability of 0.51±0.07 at 862 keV. The no flavor change hypothesis is ruled out at 5.0 σ. A global solar neutrino analysis with free fluxes determines Φ(pp)=6.06(-0.06)(+0.02)×10(10) cm(-2) s(-1) and Φ(CNO)<1.3×10(9) cm(-2) s(-1) (95% C.L.). These results significantly improve the precision with which the Mikheyev-Smirnov-Wolfenstein large mixing angle neutrino oscillation model is experimentally tested at low energy.

8.
Rev Sci Instrum ; 81(5): 053301, 2010 May.
Article in English | MEDLINE | ID: mdl-20515130

ABSTRACT

For liquid-scintillator neutrino detectors of kiloton scale, the transparency of the organic solvent is of central importance. The present paper reports on laboratory measurements of the optical scattering lengths of the organic solvents phenylxylylethane, linear alkylbenzene (LAB), and dodecane, which are under discussion for next-generation experiments such as SNO+ (Sudbury Neutrino Observatory), HanoHano, or LENA (Low Energy Neutrino Astronomy). Results comprise the wavelength range of 415-440 nm. The contributions from Rayleigh and Mie scattering as well as from absorption/re-emission processes are discussed. Based on the present results, LAB seems to be the preferred solvent for a large-volume detector.

9.
Tissue Antigens ; 76(2): 110-8, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20403140

ABSTRACT

Necrotizing meningoencephalitis (NME) is a disorder of Pug Dogs that appears to have an immune etiology and high heritability based on population studies. The present study was undertaken to identify a genetic basis for the disease. A genome-wide association scan with single tandem repeat (STR) markers showed a single strong association near the dog leukocyte antigen (DLA) complex on CFA12. Fine resolution mapping with 27 STR markers on CFA12 further narrowed association to the region containing DLA-DRB1, -DQA1 and, -DQB1 genes. Sequencing confirmed that affected dogs were more likely to be homozygous for specific alleles at each locus and that these alleles were linked, forming a single high risk haplotype. The strong DLA class II association of NME in Pug Dogs resembles that of human multiple sclerosis (MS). Like MS, NME appears to have an autoimmune basis, involves genetic and nongenetic factors, has a relatively low incidence, is more frequent in females than males, and is associated with a vascularly orientated nonsuppurative inflammation. However, NME of Pug Dogs is more aggressive in disease course than classical human MS, appears to be relatively earlier in onset, and involves necrosis rather than demyelination as the central pathobiologic feature. Thus, Pug Dog encephalitis (PDE) shares clinical features with the less common acute variant forms of MS. Accordingly, NME of Pug Dogs may represent a naturally occurring canine model of certain idiopathic inflammatory disorders of the human central nervous system.


Subject(s)
Dog Diseases/genetics , Dog Diseases/immunology , Histocompatibility Antigens Class I/genetics , Meningoencephalitis/veterinary , Multiple Sclerosis/genetics , Multiple Sclerosis/immunology , Alleles , Animals , Base Sequence , DNA Primers/genetics , Disease Models, Animal , Dogs , Exons , Female , Gene Frequency , Genes, MHC Class II , Genetic Predisposition to Disease , Genome-Wide Association Study , Haplotypes , Humans , Male , Meningoencephalitis/genetics , Meningoencephalitis/immunology , Microsatellite Repeats , Species Specificity
10.
Anim Genet ; 40(4): 569-71, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19392818

ABSTRACT

DOGSET is an online resource that provides access to primer sequences that have been computationally mined from the reference genome using heuristic algorithms. The electronic repository includes PCR primers corresponding to 32,135 markers for genetic mapping and 334,657 sequence-tagged gene elements for targeted re-sequencing and mutation discovery. A customized report that tailors primer design to wet bench protocols can be exported for a region of interest by specifying genome coordinates in a graphical user interface.


Subject(s)
Chromosome Mapping , DNA Primers , Dogs/genetics , Sequence Analysis, DNA , Software , Animals , Internet , Microsatellite Repeats
11.
Phys Rev Lett ; 101(9): 091302, 2008 Aug 29.
Article in English | MEDLINE | ID: mdl-18851600

ABSTRACT

We report the direct measurement of the 7Be solar neutrino signal rate performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso. The interaction rate of the 0.862 MeV 7Be neutrinos is 49+/-3stat+/-4syst counts/(day.100 ton). The hypothesis of no oscillation for 7Be solar neutrinos is inconsistent with our measurement at the 4sigma C.L. Our result is the first direct measurement of the survival probability for solar nu(e) in the transition region between matter-enhanced and vacuum-driven oscillations. The measurement improves the experimental determination of the flux of 7Be, pp, and CNO solar nu(e), and the limit on the effective neutrino magnetic moment using solar neutrinos.

13.
J Bone Miner Res ; 18(7): 1261-6, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12854836

ABSTRACT

UNLABELLED: Bone ultrasound measures (QUSs) can assess fracture risk in the elderly. We compared three QUSs and their association with nonvertebral fracture history in 7562 Swiss women 70-80 years of age. The association between nonvertebral fracture was higher for heel than phalangeal QUS. INTRODUCTION: Because of the high morbidity and mortality associated with osteoporotic fractures, it is essential to detect subjects at risk for such fractures with screening methods. Because quantitative bone ultrasound (QUS) discriminated subjects with osteoporotic fractures from controls in several cross-sectional studies and predicted fractures in prospective studies, QUS could be more practical than DXA for screening. MATERIAL AND METHODS: This cross-sectional and retrospective multicenter (10 centers) study was performed to compare three QUSs (two heel ultrasounds: Achilles+ [GE-Lunar] and Sahara [Hologic]; the phalanges: ultrasound DBM sonic 1200 [IGEA]) for determining by logistic regression nonvertebral fracture odds ratio (OR) in a sample of 7562 Swiss women, 75.3 +/- 3.1 years of age. The two heel QUSs measured the broadband ultrasound attenuation (BUA) and the speed of sound (SOS). In addition, Achilles+ calculated the stiffness index (SI) and the Sahara calculated the quantitative ultrasound index (QUI) from BUA and SOS. The DBM sonic 1200 measured the amplitude-dependent SOS (AD-SOS). RESULTS: Eighty-six women had a history of a traumatic hip fracture after the age of 50, 1594 had a history of forearm fracture, and 2016 had other nonvertebral fractures. No fracture history was reported by 3866 women. Discrimination for hip fracture was higher than for the other nonvertebral fractures. The two heel QUSs had a significantly higher discrimination power than the QUSs of the phalanges, with standardized ORs, adjusted for age and body mass index, ranging from 2.1 to 2.7 (95% CI = 1.6, 3.5) compared with 1.4 (95% CI = 1.1, 1.7) for the AD-SOS of DBM sonic 1200. CONCLUSION: This study showed a high association between heel QUS and hip fracture history in elderly Swiss women. This could justify integration of QUS among screening strategies for identifying elderly women at risk for osteoporotic fractures.


Subject(s)
Bone and Bones/diagnostic imaging , Fractures, Bone/complications , Fractures, Bone/diagnostic imaging , Osteoporosis, Postmenopausal/complications , Osteoporosis, Postmenopausal/diagnostic imaging , Age Factors , Aged , Aged, 80 and over , Body Mass Index , Calibration , Cross-Sectional Studies , Female , Humans , Mass Screening/methods , Odds Ratio , Retrospective Studies , Risk Factors , Switzerland , Ultrasonography
14.
J Clin Densitom ; 5(4): 335-41, 2002.
Article in English | MEDLINE | ID: mdl-12665633

ABSTRACT

Because of the important morbidity and mortality associated with osteoporosis, it is essential to detect subjects at risk by screening methods, such as bone quantitative ultrasounds (QUSs). Several studies showed that QUS could predict fractures. None, however, compared prospectively different QUS devices, and few data of quality controls (QCs) have been published. The Swiss Evaluation of the Methods of Measurement of Osteoporotic Fracture Risk is a prospective multicenter study that compared three QUSs for the assessment of hip fracture risk in a population of 7609 women age >/=70 yr. Because the inclusion phase lasted 20 mo, and because 10 centers participated in this study, QC became a major issue. We therefore developed a QC procedure to assess the stability and precision of the devices, and for their cross-calibration. Our study focuses on the two heel QUSs. The water bath system (Achilles+) had a higher precision than the dry system (Sahara). The QC results were highly dependent on temperature. QUS stability was acceptable, but Sahara must be calibrated regularly. A sufficient homogeneity among all the Sahara devices could be demonstrated, whereas significant differences were found among the Achilles+ devices. For speed of sound, 52% of the differences among the Achilles+ was explained by the water s temperature. However, for broadband ultrasound attenuation, a maximal difference of 23% persisted after adjustment for temperature. Because such differences could influence measurements in vivo, it is crucial to develop standardized phantoms to be used in prospective multicenter studies.


Subject(s)
Calcaneus/diagnostic imaging , Fractures, Bone/diagnostic imaging , Osteoporosis/complications , Ultrasonography/instrumentation , Ultrasonography/standards , Calibration , Fractures, Bone/etiology , Humans , Multicenter Studies as Topic , Phantoms, Imaging , Quality Control , Temperature
18.
Semin Respir Crit Care Med ; 22(3): 237-46, 2001 Jun.
Article in English | MEDLINE | ID: mdl-16088676

ABSTRACT

Acute lung injury (ALI) remains a serious threat to critically ill patients and continues to pose challenges to clinicians and investigators as they strive to better identify and treat these patients. Over 30 years of clinical and basic science investigations have led to a better understanding of the pathophysiology, risk factors, and prognosis of this entity but we still lack a "gold standard'' for its identification. The American-European Consensus Conference definition has helped in the effort to standardize the definition of ALI but is still fraught with difficulties in the application of criteria for the chest radiograph, hypoxemia, and left atrial hypertension. As further efforts are undertaken to better define ALI and to more accurately describe its incidence, it is critical that methodology to assess the accuracy and reliability of such definitions be utilized. This union of clinical epidemiology, clinical research, and basic science will not only better describe the population burden of ALI but will also better track the effect of current and future therapeutic interventions.

19.
Inj Prev ; 6(3): 219-22, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11003189

ABSTRACT

OBJECTIVE: Certain family structures have been identified as putting children at high risk for injury. To further define children at highest risk, we set out to explore the effect of an older sibling and birth interval on the risk of injury related hospital admission or death. METHODS: Data were analyzed using a case-control design. Cases and controls were identified by linking longitudinal birth data from Washington state (1989-96) to death certificate records and hospital discharge data obtained from the Washington State Comprehensive Hospital Abstract Reporting System and frequency matched in a 1:2 ratio on year of birth. Cases consisted of singleton children 6 years of age or younger who were hospitalized or died as a result of injury during the years 1989-96. Multivariate logistic regression was used to identify and adjust for confounding variables. RESULTS: There were 3145 cases and 8371 controls. The adjusted odds ratio for injury in children with an older sibling was 1.50 (95% confidence interval 1.37 to 1.65). The effect was greatest in children under 2 years of age, and in those with a birth interval of less than two years. As the number of older siblings increased, so did the risk of injury, with the highest risk in children with three or more older siblings. CONCLUSION: These data suggest that the presence of an older sibling is associated with an increased risk of injury. The risk is highest in those with very short birth intervals. Potential mechanisms for this increased risk may relate to inadequate parental supervision. Pediatricians and other care providers need to be alert to these identifiable risk factors and then direct preventive strategies, such as home visits and educational programs, toward these families.


Subject(s)
Birth Intervals , Child Welfare/statistics & numerical data , Family Characteristics , Nuclear Family , Wounds and Injuries/etiology , Wounds and Injuries/mortality , Birth Certificates , Case-Control Studies , Child , Child, Preschool , Confounding Factors, Epidemiologic , Death Certificates , Educational Status , Female , Hospitalization/statistics & numerical data , Humans , Infant , Infant Mortality , Infant, Newborn , Logistic Models , Male , Multivariate Analysis , Parenting , Risk Factors , Socioeconomic Factors , Washington/epidemiology , Wounds and Injuries/prevention & control
20.
J Trauma ; 49(2): 281-5, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10963540

ABSTRACT

BACKGROUND: An unrecognized, or occult, injury is particularly dangerous in trauma patients, who often have multiple life-threatening injuries. We sought to determine the frequency and quantify the utility of the abdominal computed tomographic (CT) scan in detecting occult pneumothoraces. METHODS: Charts of all trauma patients diagnosed with a pneumothorax over a 7-year period were retrospectively reviewed for findings on admission chest radiograph, abdominal CT scan, and other demographic data. RESULTS: A total of 312 charts were reviewed, with 230 patients identified as having a pneumothorax at admission. Of the 230 patients, 126 (54.8%) had an occult pneumothorax identified on abdominal CT scan. In these patients, the mean Trauma Score was 14.1 +/- 2.9 and the mean Injury Severity Score was 24.1 +/- 11.2. In the group of occult pneumothoraces, 84 (66.7%) underwent chest tube placement. CONCLUSIONS: Abdominal CT scanning provided important information about thoracic trauma often missed on initial evaluation in the trauma bay. This information frequently affected the patient's clinical management.


Subject(s)
Abdominal Injuries/diagnostic imaging , Multiple Trauma/diagnostic imaging , Pneumothorax/diagnostic imaging , Pneumothorax/epidemiology , Tomography, X-Ray Computed/standards , Adult , Female , Humans , Incidence , Injury Severity Score , Male , Medical Records , Pennsylvania/epidemiology , Predictive Value of Tests , Retrospective Studies
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