Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current (NC), elastic scattering, and charged current reactions and ...assuming the standard 8B shape, the nu(e) component of the 8B solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a kinetic energy threshold of 5 MeV. The non-nu(e) component is phi(mu)(tau) = 3.41(+0.45)(-0.45)(stat)(+0.48)(-0.45)(syst) x 10(6) cm(-2) s(-1), 5.3sigma greater than zero, providing strong evidence for solar nu(e) flavor transformation. The total flux measured with the NC reaction is phi(NC) = 5.09(+0.44)(-0.43)(stat)(+0.46)(-0.43)(syst) x 10(6) cm(-2) s(-1), consistent with solar models.
The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is ...14.0%+/-6.3%(+1.5%)(-1.4%) of the average rate. If the total flux of active neutrinos is additionally constrained to have no asymmetry, the nu(e) asymmetry is found to be 7.0%+/-4.9%(+1.3%)(-1.2%). A global solar neutrino analysis in terms of matter-enhanced oscillations of two active flavors strongly favors the large mixing angle solution.
Solar fusion cross sections Adelberger, Eric G.; Austin, Sam M.; Bahcall, John N. ...
Reviews of modern physics,
10/1998, Letnik:
70, Številka:
4
Journal Article
Standard applanation tonometers are subject to systematic errors when applied to corneas with non-standard properties. Dynamic contour tonometry has been proposed as an alternative method for ...obtaining correct IOP data from such corneas. We have examined its applicability for patients who have undergone LASIK surgery.
20 healthy individuals scheduled for bilateral myopic LASIK were selected. Pre- and postoperative examination (3 months) included applanation tonometry (Goldmann), contour tonometry, pachymetry, keratometry, and refraction. LASIK was performed with an MEL-70 Excimer Laser and a Hansatome Microkeratome. A tobramycin/dexamethasone preparation (Tobradex eye drops) was prescribed during one week after surgery.
Applanation tonometry and contour tonometry furnished comparable IOP results prior to surgery (GAT: 15.1 +/- 2.2 mm Hg mean +/- SD DCT: 17.0 +/- 2.2 mm Hg), with corneal thickness ranging from 473 - 601 micro m (mean: 555 micro m). 3 months postoperatively, mean corneal thickness was reduced by - 85 micro m. Contour tonometer readings were not significantly different from preoperative results (16.0 +/- 2.4 mm Hg); whereas the Goldmann tonometer furnished significantly lower values at 11.8 +/- 1.3 mm Hg.
Preoperative IOP measurements with the two types of tonometer were in good agreement. Post-operative results with the contour tonometer agree well with preoperative figures. However, the Goldmann tonometer furnishes values 3.3 mm Hg lower on average. This result is indicative of a significant measurement error of this device on post-LASIK eyes, which persists even 3 months postoperatively. The Dynamic contour tonometer appears to be suitable, reliable, and easy to use for IOP measurements after LASIK surgery.
Results are reported from a joint analysis of Phase I and Phase II data from the Sudbury Neutrino Observatory. The effective electron kinetic energy threshold used is T{sub eff}=3.5 MeV, the lowest ...analysis threshold yet achieved with water Cherenkov detector data. In units of 10{sup 6} cm{sup -2} s{sup -1}, the total flux of active-flavor neutrinos from {sup 8}B decay in the Sun measured using the neutral current (NC) reaction of neutrinos on deuterons, with no constraint on the {sup 8}B neutrino energy spectrum, is found to be PHI{sub NC}=5.140{sub -0.158}{sup +0.160}(stat){sub -0.117}{sup +0.132}(syst). These uncertainties are more than a factor of 2 smaller than previously published results. Also presented are the spectra of recoil electrons from the charged current reaction of neutrinos on deuterons and the elastic scattering of electrons. A fit to the Sudbury Neutrino Observatory data in which the free parameters directly describe the total {sup 8}B neutrino flux and the energy-dependent nu{sub e} survival probability provides a measure of the total {sup 8}B neutrino flux PHI{sub {sup 8}{sub B}}=5.046{sub -0.152}{sup +0.159}(stat){sub -0.123}{sup +0.107}(syst). Combining these new results with results of all other solar experiments and the KamLAND reactor experiment yields best-fit values of the mixing parameters of theta{sub 12}=34.06{sub -0.84}{sup +1.16} degrees and DELTAm{sub 21}{sup 2}=7.59{sub -0.21}{sup +0.20}x10{sup -5} eV{sup 2}. The global value of PHI{sup 8}{sub B} is extracted to a precision of {sub -2.95}{sup +2.38}%. In a three-flavor analysis the best fit value of sin{sup 2}theta{sub 13} is 2.00{sub -1.63}{sup +2.09}x10{sup -2}. This implies an upper bound of sin{sup 2}theta{sub 13}<0.057 (95% C.L.).
Abstract Background/Purpose Various different regimes exist for the treatment of hereditary pancreatitis in childhood. Here, we propose a therapeutic pathway with emphasis on endoscopic and surgical ...procedures. Methods From 2006 to 2013, 12 patients with a diagnosis of hereditary pancreatitis were prospectively included in a therapeutic step-up schema. The treatment outcome was evaluated and correlated to aetiological factors and pathoanatomic findings. Results After diagnostic work-up (laboratory data, ultrasound examination, magnetic resonance cholangiopancreatography and genetic testing), all 12 patients underwent early endoscopic retrograde cholangiopancreatography (ERCP), which was successfully performed in ten children. Obstructive pancreatitis was found in eight children, and required sphincterotomy, dilation and stenting for 12 months. In two children with unsuccessful ERCP, open surgical drainage procedures were performed. After a mean follow-up of 32 months all children are free of recurrence of pancreatitis without any impairment of everyday activities. Conclusions For children with hereditary pancreatitis, a therapeutic step plan with early ERCP and open surgical drainage procedures in case of impossible or insufficient endoscopic treatment prevents recurring pancreatitis and offers a normal quality of life without any major complications.
The Sudbury Neutrino Observatory Boger, J; Hahn, R.L; Rowley, J.K ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2000, Letnik:
449, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The Sudbury Neutrino Observatory is a second-generation water Cherenkov detector designed to determine whether the currently observed solar neutrino deficit is a result of neutrino oscillations. The ...detector is unique in its use of D
2O as a detection medium, permitting it to make a solar model-independent test of the neutrino oscillation hypothesis by comparison of the charged- and neutral-current interaction rates. In this paper the physical properties, construction, and preliminary operation of the Sudbury Neutrino Observatory are described. Data and predicted operating parameters are provided whenever possible.
Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to "invisible" modes, such as n-->3nu. The analysis was based on a search for gamma rays from the ...deexcitation of the residual nucleus that would result from the disappearance of either a proton or neutron from 16O. A limit of tau(inv)>2 x 10(29) yr is obtained at 90% confidence for either neutron- or proton-decay modes. This is about an order of magnitude more stringent than previous constraints on invisible proton-decay modes and 400 times more stringent than similar neutron modes.
Vascular endothelial cells lost from the bloodvessel endothelium through necrosis or apoptosis must be replaced. We investigated in a leukaemia model whether bone-marrow-derived endothelial cells ...contribute to this maintenance angiogenesis.
We studied six patients with chronic myelogenous leukaemia (CML) carrying the
BCR/ABL fusion gene in their bone-marrow-derived cells. We screened endothelial cells generated in vitro from bone-marrow-derived progenitor cells and vascular endothelium in myocardial tissue for the
BCR/ABL fusion gene by in-situ hybridisation. For detection of donor-type endothelial cells after transplantation of haemopoietic stem cells, recipient tissue was stained with monoclonal antibodies against donor-type HLA antigens.
We identified the
BCR/ABL fusion gene in variable proportions (0·56%) of endothelial cells generated in vitro. Endothelial cells expressing the fusion gene were found in the vascular endothelium of a patient. In a recipient of an allogeneic stem-cell transplant, normal donor-type endothelial cells were detected in the vascular endothelium.
These findings suggest that CML is not solely a haematological disease but originates from a bone-marrow-derived haemangioblastic precursor cell that can give rise to both blood cells and endothelial cells. Moreover, normal bone-marrow-derived endothelial cells can contribute to the maintenance of the blood vascular endothelium. The integration of bone-marrow-derived endothelial cells into the vascular endothelium provides a rationale for developing vascular targeting strategies in vasculopathies, inflammatory diseases, and cancer.
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