New limits are presented on the cross section for weakly interacting massive particle (WIMP) nucleon scattering in the KIMS CsI(Tℓ) detector array at the Yangyang Underground Laboratory. The exposure used for these results is 24 524.3  kg·days. Nuclei recoiling from WIMP interactions are identified by a pulse shape discrimination method. A low energy background due to alpha emitters on the crystal surfaces is identified and taken into account in the analysis. The detected numbers of nuclear recoils are consistent with zero and 90% confidence level upper limits on the WIMP interaction rates are set for electron equivalent energies from 3 to 11 keV. The 90% upper limit of the nuclear recoil event rate for 3.6-5.8 keV corresponding to 2-4 keV in NaI(Tℓ) is 0.0098 counts/kg/keV/day, which is below the annual modulation amplitude reported by DAMA. This is incompatible with interpretations that enhance the modulation amplitude such as inelastic dark matter models. We establish the most stringent cross section limits on spin-dependent WIMP-proton elastic scattering for the WIMP masses greater than 20  GeV/c2.

The purpose of this study was to evaluate the geometry and surface characteristics of osseointegration after functional loading by radiographic, periodontal and histomorphometric analyses. We analysed three groups of implants with different geometry and surface characteristics using experimental dogs. The control group received Brånemark implants (group 1). Group 2 and group 3 implants each had a 0.5-mm pitch height but differed in surface characteristics. Group 2 implants were machine surfaced and group 3 implants were thermally oxidized at 800 degrees C for 2 h in a pure oxygen atmosphere. For these experiments, which used a total of four healthy beagle dogs, the implants were randomly installed into the extracted first, second and third premolar positions. The animals received radiographic and clinical periodontal examinations at 6 and 12 months post-loading, and were then killed for histomorphometric analysis. The radiographic analysis showed that mean crestal bone resorption in the control group was greater than that observed in the experimental groups (P < 0.05). The percentage of bone-to-implant contact for group 3 (83.7%) was significantly higher than in groups 1 (74.4%) and 2 (75.0%) (P < 0.05). Overall, implant geometry and surface treatment affected the rate of crestal bone resorption and bone healing surrounding the dental implants.

SummaryThis study compared cerebral blood flow–carbon dioxide (CBF–CO2) reactivities in the supine and modest Trendelenburg position under pnemoperitoneum during sevoflurane anaesthesia. After induction of anaesthesia in 25 patients, mechanical ventilation was adjusted to increase Paco2 from 4.7 (T1) to 6.0 kPa (T2) in the supine position, and the change in jugular bulb oxygen saturation was measured as an index of CBF. Then, after establishment of pneumoperitoneum and 30° Trendelenburg position, the CO2 step and measurement of CBF were repeated. The CBF–CO2 reactivity was 7.5 (3.3) %.kPa−1 (% change in jugular bulb oxygen saturation per unit change in Paco2) in the supine position and 6.8 (2.3) %.kPa−1 in the 30° Trendelenburg‐pneumoperitoneum condition (p = 0.086). We conclude that CBF–CO2 reactivity is unchanged by the modest Trendelenburg position under pneumoperitoneum during sevoflurane anaesthesia.

Giant unilamellar vesicles, prepared by hydrating a synthetic lipid, are visible under phase-contrast microscopy. Additives injected into or onto the vesicles induce various morphological changes that have been recorded photographically. For example, KVI2 creates a large, slowly-healing hole in the vesicle surface to form a solvent-filled "nanocup". Sodium cholate (a bile salt) also injures the vesicle surface, but the defect is smaller and heals rapidly. Sodium acetate induces vesicle fusion, a process explainable by the Svetina-Zeks mechanism. Poly(viny1 alcohol) causes filament-connected vesicles (but not isolated vesicles) to fuse. This observation leads to the speculation that many fusion experiments with submicroscopic vesicles might also reflect, unknowingly, the presence of intervesicular filaments. Severe osmotic stress, as provided by 0.1 M NaBr, forces the vesicles to undulate vigorously. Finally, injection of a fluorescent dye into the vesicles allows, via fluorescent microscopy, the detection of outward diffusion by the dye. Giant vesicles provide a particularly valuable membrane model because, unlike submicroscopic vesicles on which the bulk of bilayer research has thus far been focused, the results are not affected by an unnatural membrane curvature. Moreover, morphological changes can be monitored as a function of membrane composition and experimental conditions without relying on indirect spectroscopic methods.

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