[en] Isogeneic intestinal transplantation of iron-loaded and iron-deficient intestine into iron-deficient rats was performed in 20 Lewis rats to isolate the effect of intestinal mucosal iron on iron absorption. Rats were iron loaded with three weekly IM injections of 50 mg of iron dextran and were rendered iron deficient with an iron-deficient diet for 3 weeks. Iron status was assessed by hepatic and gut mucosal iron determination. Uptake and transfer of 59Fe-ascorbate was measured in an isolated perfused segment of transplanted intestine 48 hours after transplantation. The mean rate of uptake of 59Fe from an iron-loaded intestine (mean mucosal iron concentration, 7.97 +/- 2.02 mumol/g) was 431 +/- 27 nmol/30 min, and from an iron-deficient intestine (mean mucosal iron concentration, 1.35 +/- .84 mumol/g), 743 +/- 222 nmol/30 min (P less than 0.001). The mean transfer of 59Fe from the mucosal cell to the body through an iron-loaded intestine was 63 +/- 22 nmol/30 min, and through an iron-deficient intestine was 86 +/- 32 nmol/30 min (P less than 0.05). These results suggest that the gut mucosal iron concentration regulates the uptake and transfer of iron in the intestine

[en] The Cryogenic Dark Matter Search (CDMS) is an experiment to detect weakly interacting massive particles (WIMPs), which may constitute the universe's dark matter, based on their interactions with Ge and Si nuclei. We report the results of an analysis of data from the first two runs of CDMS at the Soudan Underground Laboratory in terms of spin-dependent WIMP-nucleon interactions on ⁷³Ge and ²⁹Si. These data exclude new regions of WIMP parameter space, including regions relevant to spin-dependent interpretations of the annual modulation signal reported by the DAMA/NaI experiment

[en] We report new results from the Cryogenic Dark Matter Search (CDMS II) at the Soudan Underground Laboratory. Two towers, each consisting of six detectors, were operated for 74.5 live days, giving spectrum-weighted exposures of 34 (12) kg d for the Ge (Si) targets after cuts, averaged over recoil energies 10-100 keV for a weakly interacting massive particle (WIMP) mass of 60 GeV/c². A blind analysis was conducted, incorporating improved techniques for rejecting surface events. No WIMP signal exceeding expected backgrounds was observed. When combined with our previous results from Soudan, the 90% C.L. upper limit on the spin-independent WIMP-nucleon cross section is 1.6x10^-43 cm² from Ge and 3x10^-42 cm² from Si, for a WIMP mass of 60 GeV/c². The combined limit from Ge (Si) is a factor of 2.5 (10) lower than our previous results and constrains predictions of supersymmetric models

[en] The optical properties of the Sudbury Neutrino Observatory (SNO) heavy water Cherenkov neutrino detector are measured in situ using a light diffusing sphere ('laserball'). This diffuser is connected to a pulsed nitrogen/dye laser via specially developed underwater optical fibre umbilical cables. The umbilical cables are designed to have a small bending radius, and can be easily adapted for a variety of calibration sources in SNO. The laserball is remotely manipulated to many positions in the D₂O and H₂O volumes, where data at six different wavelengths are acquired. These data are analysed to determine the absorption and scattering of light in the heavy water and light water, and the angular dependence of the response of the detector's photomultiplier tubes. This paper gives details of the physical properties, construction, and optical characteristics of the laserball and its associated hardware

[en] The Sudbury Neutrino Observatory is a 1000 T D₂O Cerenkov detector that is sensitive to ⁸B solar neutrinos. The energy, radius, and direction with respect to the sun is measured for each neutrino event; these distributions are used to separately determine the rates of the charged current, neutral current and electron scattering reactions of neutrinos on deuterium. Assuming an undistorted ⁸B spectrum, the ν_e component of the ⁸B solar flux is phi_e = 1.76^+0.05_-0.05(stat.)^+0.09_-0.09 (syst.) x 10⁶ cm^-2s^-1 based on events with a measured kinetic energy above 5 MeV. The non-ν_e component is phi_μτ 3.41^+0.45_-0.45(stat.)^+0.48_-0.45 (syst.) x 10⁶ cm^-2s^-1, 5.3σ greater than zero, providing strong evidence for solar ν_e flavor transformation. The total flux measured with the NC reaction is phi_NC = 5.09^+0.044_-0.43(stat.)^+0.46_-0.43 (sy st.) x 10⁶ cm^-2s^-1, consistent with solar models. 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 ν_e asymmetry is found to be 7.0% ± 4.9%^+1.3_-1.2%. A global solar neutrino analysis is terms of matter-enhanced oscillations of two active flavors strongly favors the Large Mixing Angle (LMA) solution

No abstract available

[en] The Sudbury Neutrino Observatory (SNO) has precisely determined the total active (v_x)⁸B solar neutrino flux without assumptions about the energy dependence of the v_e survival probability. The measurements were made with dissolved NaCl in the heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21+-0.27 (stat)+-0.38(syst)x10^-6 cm^-2s^-1, in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Δm² = 7.1^+1.2_-0.6 x 10^-5 eV² and θ 32.5^+2.4_-2.3 degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations

[en] The Sudbury Neutrino Observatory (SNO) is a water imaging Cherenkov detector. Its usage of 1000 metric tons of D₂O as target allows the SNO detector to make a solar-model independent test of the neutrino oscillation hypothesis by simultaneously measuring the solar ν_e flux and the total flux of all active neutrino species. Solar neutrinos from the decay of ⁸B have been detected at SNO by the charged-current (CC) interaction on the deuteron and by the elastic scattering (ES) of electrons. While the CC reaction is sensitive exclusively to ν_e, the ES reaction also has a small sensitivity to ν_μ and ν_τ. In this paper, recent solar neutrino results from the SNO experiment are presented. It is demonstrated that the solar flux from ⁸B decay as measured from the ES reaction rate under the no-oscillation assumption is consistent with the high precision ES measurement by the Super-Kamiokande experiment. The ν_e flux deduced from the CC reaction rate in SNO differs from the Super-Kamiokande ES results by 3.3σ. This is evidence for an active neutrino component, in additional to ν_e, in the solar neutrino flux. These results also allow the first experimental determination of the total active ⁸B neutrino flux from the Sun, and is found to be in good agreement with solar model predictions

[en] 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 D₂O 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