Explore the vast range of titles available.

Bone formation and remodeling occurs throughout life and requires the sustained activity of osteoblasts and osteoclasts, particularly during periods of rapid bone growth. Despite increasing evidence linking bone cell activity to global energy homeostasis, little is known about the relative energy requirements or substrate utilization of bone cells. In these studies, we measured the uptake and distribution of glucose in the skeleton in vivo using positron-emitting 18F-fluorodeoxyglucose （[lSF]-FDG） and non-invasive, high-resolution positron emission tomography/computed tomography （PE~/CT） imaging and ex vivo autoradiography. Assessment of [~SF]-FDG uptake demonstrated that relative to other tissues bone accumulated a significant fraction of the total dose of the glucose analog..Skeletal accumulation was greatest in young mice undergoing the rapid bone formation that characterizes early development. PET/CT imaging revealed that [lSF]-FDG uptake was greatest in the epiphyseal and metaphyseal regions of long bones, which accords with the increased osteoblast numbers and activity at this skeletal site. Insulin administration significantly increased skeletal accumulation of [lSF]-FDG, while uptake was reduced in mice lacking the insulin receptor specifically in osteoblasts or fed a high-fat diet. Our results indicated that the skeleton is a site of significant glucose uptake and that its consumption by bone cells is subject to regulation by insulin and disturbances in whole-body metabolism.

The possibility to probe new physics scenarios of light Majorana neutrino exchange and right-handed currents at the planned next generation neutrinoless double β decay experiment SuperNEMO is discussed. Its ability to study different isotopes and track the outgoing electrons provides the means to discriminate different underlying mechanisms for the neutrinoless double β decay by measuring the decay half-life and the electron angular and energy distributions.

The NEMO-3 results for the double-$$\\beta $$β decay of$$^{150}$$150 Nd to the 0$$^+_1$$1 + and 2$$^+_1$$1 + excited states of$$^{150}$$150 Sm are reported. The data recorded during 5.25 year with 36.6 g of the isotope$$^{150}$$150 Nd are used in the analysis. The signal of the$$2\\nu \\beta \\beta $$2 ν β β transition to the 0$$^+_1$$1 + excited state is detected with a statistical significance exceeding 5$$\\sigma $$σ . The half-life is measured to be$$T_{1/2}^{2\\nu \\beta \\beta }(0^+_1) = \\left[ 1.11 ^{+0.19}_{-0.14} \\,\\left( \\hbox {stat}\\right) ^{+0.17}_{-0.15}\\,\\left( \\hbox {syst}\\right) \\right] \\times 10^{20}$$T 1 / 2 2 ν β β ( 0 1 + ) = 1 . 11 - 0.14 + 0.19 stat - 0.15 + 0.17 syst × 10 20  year, which is the most precise value that has been measured to date. 90% confidence-level limits are set for the other decay modes. For the$$2\\nu \\beta \\beta $$2 ν β β decay to the 2$$^+_1$$1 + level the limit is$$T^{2\\nu \\beta \\beta }_{1/2}(2^+_1) > 2.42 \\times 10^{20}~\\hbox {year}$$T 1 / 2 2 ν β β ( 2 1 + ) > 2.42 × 10 20 year . The limits on the$$0\\nu \\beta \\beta $$0 ν β β decay to the 0$$^+_1$$1 + and 2$$^+_1$$1 + levels of$$^{150}$$150 Sm are significantly improved to$$T_{1/2}^{0\\nu \\beta \\beta }(0^+_1) > 1.36 \\times 10^{22}~\\hbox {year}$$T 1 / 2 0 ν β β ( 0 1 + ) > 1.36 × 10 22 year and$$T_{1/2}^{0\\nu \\beta \\beta }(2^+_1) > 1.26 \\times 10^{22}~\\hbox {year}$$T 1 / 2 0 ν β β ( 2 1 + ) > 1.26 × 10 22 year .

Abstract The NEMO-3 results for the double-β β decay of¹⁵⁰150 Nd to the 0⁺₁1 + and 2⁺₁1 + excited states of¹⁵⁰150 Sm are reported. The data recorded during 5.25 year with 36.6 g of the isotope¹⁵⁰150 Nd are used in the analysis. The signal of the2ν β β 2 ν β β transition to the 0⁺₁1 + excited state is detected with a statistical significance exceeding 5σ σ . The half-life is measured to beT_(1/2)^(2ν β β)(0⁺₁) = \\left[ 1.11 ^(+0.19)_(-0.14) \\left( \\hbox stat\\right) ^(+0.17)_(-0.15) \\left( \\hbox syst\\right) \\right] × 10²⁰T 1 / 2 2 ν β β ( 0 1 + ) = 1 . 11 - 0.14 + 0.19 stat - 0.15 + 0.17 syst × 10 20  year, which is the most precise value that has been measured to date. 90% confidence-level limits are set for the other decay modes. For the2ν β β 2 ν β β decay to the 2⁺₁1 + level the limit isT^(2ν β β)_(1/2)(2⁺₁) > 2.42 × 10²⁰ \\hbox yearT 1 / 2 2 ν β β ( 2 1 + ) > 2.42 × 10 20 year . The limits on the0ν β β 0 ν β β decay to the 0⁺₁1 + and 2⁺₁1 + levels of¹⁵⁰150 Sm are significantly improved toT_(1/2)^(0ν β β)(0⁺₁) > 1.36 × 10²² \\hbox yearT 1 / 2 0 ν β β ( 0 1 + ) > 1.36 × 10 22 year andT_(1/2)^(0ν β β)(2⁺₁) > 1.26 × 10²² \\hbox yearT 1 / 2 0 ν β β ( 2 1 + ) > 1.26 × 10 22 year .

The performance of Hamamatsu 8\" photomultiplier tubes (PMTs) of the type used in the SuperNEMO neutrinoless double-beta decay experiment (R5912-MOD), is investigated as a function of exposure to helium (He) gas. Two PMTs were monitored for over a year, one exposed to varying concentrations of He, and the other kept in standard atmospheric conditions as a control. Both PMTs were exposed to light signals generated by a Bi-207 radioactive source that provided consistent large input PMT signals similar to those that are typical of the SuperNEMO experiment. The energy resolution of PMT signals corresponding to 1 MeV energy scale determined from the Bi-207 decay spectrum, shows a negligible degradation with He exposure; however the rate of after-pulsing shows a clear increase with He exposure, which is modelled and compared to diffusion theory. A method for reconstructing the partial pressure of He within the PMT and a method for determining the He breakdown point, are introduced. The implications for long-term SuperNEMO operations are briefly discussed.

The double-beta decay of 82Se to the 0+1 excited state of 82Kr has been studied with the NEMO-3 detector using 0.93 kg of enriched 82Se measured for 4.75 y, corresponding to an exposure of 4.42 kg y. A dedicated analysis to reconstruct the gamma-rays has been performed to search for events in the 2e2g channel. No evidence of a 2nbb decay to the 0+1 state has been observed and a limit of T2n 1/2(82Se; 0+gs -> 0+1) > 1.3 1021 y at 90% CL has been set. Concerning the 0nbb decay to the 0+1 state, a limit for this decay has been obtained with T0n 1/2(82Se; 0+g s -> 0+1) > 2.3 1022 y at 90% CL, independently from the 2nbb decay process. These results are obtained for the first time with a tracko-calo detector, reconstructing every particle in the final state.

The NEMO-3 results for the double-\\(\\) decay of \\(^150\\)Nd to the 0\\(^+_1\\) and 2\\(^+_1\\) excited states of \\(^150\\)Sm are reported. The data recorded during 5.25 yr with 36.6 g of the isotope \\(^150\\)Nd are used in the analysis. For the first time, the signal of the \\(2\\) transition to the 0\\(^+_1\\) excited state is detected with a statistical significance exceeding 5\\(\\). The half-life is measured to be \\(T_1/2^2(0^+_1) = [ 1.11 ^+0.19_-0.14 \\,(stat) ^+0.17_-0.15\\, (syst) ] 10^20\\,yr\\). The limits are set on the \\(2\\) decay to the 2\\(^+_1\\) level and on the \\(0\\) decay to the 0\\(^+_1\\) and 2\\(^+_1\\) levels of \\(^150\\)Sm.

SuperNEMO is a double-\\(\\beta\\) decay experiment, which will employ the successful tracker-calorimeter technique used in the recently completed NEMO-3 experiment. SuperNEMO will implement 100 kg of double-\\(\\beta\\) decay isotope, reaching a sensitivity to the neutrinoless double-\\(\\beta\\) decay (\\(0\\nu\\beta\\beta\\)) half-life of the order of \\(10^{26}\\) yr, corresponding to a Majorana neutrino mass of 50-100 meV. One of the main goals and challenges of the SuperNEMO detector development programme has been to reach a calorimeter energy resolution, \\(\\Delta\\)E/E, around 3%/\\(sqrt(E)\\)(MeV) \\(\\sigma\\), or 7%/\\(sqrt(E)\\)(MeV) FWHM (full width at half maximum), using a calorimeter composed of large volume plastic scintillator blocks coupled to photomultiplier tubes. We describe the R\\&D programme and the final design of the SuperNEMO calorimeter that has met this challenging goal.

The BiPo-3 detector, running in the Canfranc Underground Laboratory (Laboratorio Subterráneo de Canfranc, LSC, Spain) since 2013, is a low-radioactivity detector dedicated to measuring ultra low natural radionuclide contaminations of \\(^{208}\\)Tl (\\(^{232}\\)Th chain) and \\(^{214}\\)Bi (\\(^{238}\\)U chain) in thin materials. The total sensitive surface area of the detector is 3.6 m\\(^2\\). The detector has been developed to measure radiopurity of the selenium double \\(\\beta\\)-decay source foils of the SuperNEMO experiment. In this paper the design and performance of the detector, and results of the background measurements in \\(^{208}\\)Tl and \\(^{214}\\)Bi, are presented, and validation of the BiPo-3 measurement with a calibrated aluminium foil is discussed. Results of the \\(^{208}\\)Tl and \\(^{214}\\)Bi activity measurements of the first enriched \\(^{82}\\)Se foils of the double \\(\\beta\\)-decay SuperNEMO experiment are reported. The sensitivity of the BiPo-3 detector for the measurement of the SuperNEMO \\(^{82}\\)Se foils is \\(\\mathcal{A}\\)(\\(^{208}\\)Tl) \\(<2\\) \\(\\mu\\)Bq/kg (90\\% C.L.) and \\(\\mathcal{A}\\)(\\(^{214}\\)Bi) \\(<140\\) \\(\\mu\\)Bq/kg (90\\% C.L.) after 6 months of measurement.