Solar Neutrinos: Status and Prospects Haxton, W.C; Hamish Robertson, R.G; Serenelli, Aldo M
Annual review of astronomy and astrophysics,
08/2013, Volume:
51, Issue:
1
Journal Article
Peer reviewed
Open access
We describe the current status of solar neutrino measurements and of the theory-both neutrino physics and solar astrophysics-employed in interpreting measurements. Important recent developments ...include Super-Kamiokande's determination of the ν−e elastic scattering rate for
8
B neutrinos to 3%; the latest Sudbury Neutrino Observatory (SNO) global analysis in which the inclusion of low-energy data from SNO I and II significantly narrowed the range of allowed values for the neutrino mixing angle
θ
12
; Borexino results for both the
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Be and proton-electron-proton (pep) neutrino fluxes, the first direct measurements constraining the rate of proton-proton (pp) I and pp II burning in the Sun; global reanalyses of solar neutrino data that take into account new reactor results on
θ
13
; a new decadal evaluation of the nuclear physics of the pp chain and CNO cycle defining best values and uncertainties in the nuclear microphysics input to solar models; recognition of an emerging discrepancy between two tests of solar metallicity, helioseismological mappings of the sound speed in the solar interior, and analyses of the metal photoabsorption lines based on our best current description of the Sun's photosphere; a new round of standard solar model calculations optimized to agree either with helioseismology or with the new photospheric analysis; and, motivated by the solar abundance problem, the development of nonstandard, accreting solar models, in order to investigate possible consequences of the metal segregation that occurred in the proto-solar disk. We review this progress and describe how new experiments such as SNO+ could help us further exploit neutrinos as a unique probe of stellar interiors.
Autoantibodies may be present in a variety of underlying cancers several years before tumours can be detected and testing for their presence may allow earlier diagnosis. We report the clinical ...validation of an autoantibody panel in newly diagnosed patients with lung cancer (LC).
Three cohorts of patients with newly diagnosed LC were identified: group 1 (n = 145), group 2 (n = 241) and group 3 (n = 269). Patients were individually matched by gender, age and smoking history to a control individual with no history of malignant disease. Serum samples were obtained after diagnosis but before any anticancer treatment. Autoantibody levels were measured against a panel of six tumour-related antigens (p53, NY-ESO-1, CAGE, GBU4-5, Annexin 1 and SOX2). Assay sensitivity was tested in relation to demographic variables and cancer type/stage.
The autoantibody panel demonstrated a sensitivity/specificity of 36%/91%, 39%/89% and 37%/90% in groups 1, 2 and 3, respectively, with good reproducibility. There was no significant difference between different LC stages, indicating that the antigens included covered the different types of LC well.
This assay confirms the value of an autoantibody panel as a diagnostic tool and offers a potential system for monitoring patients at high risk of LC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The Baksan Experiment on Sterile Transitions (BEST) was designed to investigate the deficit of electron neutrinos νe observed in previous gallium-based radiochemical measurements with high-intensity ...neutrino sources, commonly referred to as the "gallium anomaly," which could be interpreted as evidence for oscillations between νe and sterile neutrino (νs) states. A 3.414-MCi 51Cr νe source was placed at the center of two nested Ga volumes and measurements were made of the production of 71Ge through the charged current reaction, 71Ga(νe,e-)71Ge, at two average distances. The measured production rates for the inner and the outer targets, respectively, are 54.9$_{-2.4}^{+2.5}$(stat)±1.4(syst) and 55.6$_{-2.6}^{+2.7}$(stat)±1.4(syst) atoms of 71Ge/d. The ratio (R) of the measured rate of 71Ge production at each distance to the expected rate from the known cross section and experimental efficiencies are Rin=0.79±0.05 and Rout=0.77±0.05. The ratio of the outer to the inner result is 0.97±0.07, which is consistent with unity within uncertainty. The rates at each distance were found to be similar, but 20%-24% lower than expected, thus reaffirming the anomaly. Therefore these results are consistent with νe→νs oscillations with a relatively large Δm2 (> 0.5 eV2) and mixing sin22θ (≈0.4).
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C_{5}, C_{6}) and factorial cumulants (κ_{5}, κ_{6}) of net-proton and proton number distributions, ...from center-of-mass energy (sqrts_{NN}) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C_{6}/C_{2} for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with QCD calculations (for baryon chemical potential, μ_{B}≤110 MeV) which contains the crossover transition range. In addition, for energies above 7.7 GeV, the measured proton κ_{n}, within uncertainties, does not support the two-component (Poisson+binomial) shape of proton number distributions that would be expected from a first-order phase transition. Taken in combination, the hyperorder proton number fluctuations suggest that the structure of QCD matter at high baryon density, μ_{B}∼750 MeV at sqrts_{NN}=3 GeV is starkly different from those at vanishing μ_{B}∼24 MeV at sqrts_{NN}=200 GeV and higher collision energies.
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We report the triton (t) production in midrapidity (|y|<0.5) Au+Au collisions at sqrts_{NN}=7.7-200 GeV measured by the STAR experiment from the first phase of the beam energy scan at the ...Relativistic Heavy Ion Collider. The nuclear compound yield ratio (N_{t}×N_{p}/N_{d}^{2}), which is predicted to be sensitive to the fluctuation of local neutron density, is observed to decrease monotonically with increasing charged-particle multiplicity (dN_{ch}/dη) and follows a scaling behavior. The dN_{ch}/dη dependence of the yield ratio is compared to calculations from coalescence and thermal models. Enhancements in the yield ratios relative to the coalescence baseline are observed in the 0%-10% most central collisions at 19.6 and 27 GeV, with a significance of 2.3σ and 3.4σ, respectively, giving a combined significance of 4.1σ. The enhancements are not observed in peripheral collisions or model calculations without critical fluctuation, and decreases with a smaller p_{T} acceptance. The physics implications of these results on the QCD phase structure and the production mechanism of light nuclei in heavy-ion collisions are discussed.
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Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC) measured the global prevalence and severity of asthma symptoms in children.
A cross-sectional questionnaire survey ...of 798 685 children aged 13-14 years from 233 centres in 97 countries, and 388 811 children aged 6-7 years from 144 centres in 61 countries, was conducted between 2000 and 2003 in >90% of the centres.
The prevalence of wheeze in the past 12 months (current wheeze) ranged from 0.8% in Tibet (China) to 32.6% in Wellington (New Zealand) in the 13-14 year olds, and from 2.4% in Jodhpur (India) to 37.6% in Costa Rica in the 6-7 year olds. The prevalence of symptoms of severe asthma, defined as >or=4 attacks of wheeze or >or=1 night per week sleep disturbance from wheeze or wheeze affecting speech in the past 12 months, ranged from 0.1% in Pune (India) to 16% in Costa Rica in the 13-14 year olds and from 0% to 20.3% in the same two centres, respectively, in the 6-7 year olds. Ecological economic analyses revealed a significant trend towards a higher prevalence of current wheeze in centres in higher income countries in both age groups, but this trend was reversed for the prevalence of severe symptoms among current wheezers, especially in the older age group.
Wide variations exist in the symptom prevalence of childhood asthma worldwide. Although asthma symptoms tend to be more prevalent in more affluent countries, they appear to be more severe in less affluent countries.
Abstract
Bumblebees are a diverse group of globally important pollinators in natural ecosystems and for agricultural food production. With both eusocial and solitary life-cycle phases, and some ...social parasite species, they are especially interesting models to understand social evolution, behavior, and ecology. Reports of many species in decline point to pathogen transmission, habitat loss, pesticide usage, and global climate change, as interconnected causes. These threats to bumblebee diversity make our reliance on a handful of well-studied species for agricultural pollination particularly precarious. To broadly sample bumblebee genomic and phenotypic diversity, we de novo sequenced and assembled the genomes of 17 species, representing all 15 subgenera, producing the first genus-wide quantification of genetic and genomic variation potentially underlying key ecological and behavioral traits. The species phylogeny resolves subgenera relationships, whereas incomplete lineage sorting likely drives high levels of gene tree discordance. Five chromosome-level assemblies show a stable 18-chromosome karyotype, with major rearrangements creating 25 chromosomes in social parasites. Differential transposable element activity drives changes in genome sizes, with putative domestications of repetitive sequences influencing gene coding and regulatory potential. Dynamically evolving gene families and signatures of positive selection point to genus-wide variation in processes linked to foraging, diet and metabolism, immunity and detoxification, as well as adaptations for life at high altitudes. Our study reveals how bumblebee genes and genomes have evolved across the Bombus phylogeny and identifies variations potentially linked to key ecological and behavioral traits of these important pollinators.
Abstract The Nottingham Prognostic Index (NPI) is a well established and widely used method of predicting survival of operable primary breast cancer. Aims Primary : To present the updated survival ...figures for each NPI Group. Secondary : From the observations to suggest reasons for the reported fall in mortality from breast cancer. Methods The NPI is compiled from grade, size and lymph node status of the primary tumour. Consecutive cases diagnosed and treated at Nottingham City Hospital in 1980–1986 ( n = 892) and 1990–1999 ( n = 2238) are compared. Changes in protocols towards earlier diagnosis and better case management were made in the late 1980s between the two data sets. Results Case survival (Breast Cancer Specific) at 10 years has improved overall from 55% to 77%. Within all Prognostic groups there are high relative and absolute risk reductions. The distribution of cases to Prognostic groups shows only a small increase in the numbers in better groups. Conclusion The updated survival figures overall and for each Prognostic group for the NPI are presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We present the theory, design, and numerical modeling of a cylindrical, two-dimensional periodic surface lattice (2D-PSL) intended for use as the interaction region of an electron beam-driven, pulsed ...source. The production of 1.95-MW peak, pulsed 0.35-THz radiation with an electronic efficiency of 24% is reported. Mode selection in the oversized cavity, where the diameter D is almost 3.5<inline-formula> <tex-math notation="LaTeX">\times</tex-math> </inline-formula> larger than the operating wavelength <inline-formula> <tex-math notation="LaTeX">\lambda </tex-math> </inline-formula>, is achieved by coupling volume and surface fields to form a coupled cavity eigenmode. We demonstrate the advantages (including enhanced output power and improved spectral purity) of using a 2D-PSL over a simpler 1-D structure. The cylindrical <inline-formula> <tex-math notation="LaTeX">\textit{D}/\lambda \sim \text{3.5}</tex-math> </inline-formula> 2D-PSL demonstrates the "proof-of-principle" high-order mode coupling with the potential to increase <inline-formula> <tex-math notation="LaTeX">\textit{D}/\lambda </tex-math> </inline-formula> to values of 20 or more for the realization of CW 2D-PSL sources or very powerful pulsed sources. The theory is applicable over a broad frequency range.
OBJECTIVES
To compare the specificity and sensitivity of different definitions of biochemical failure in patients treated with high‐intensity focused ultrasound (HIFU) for prostate cancer, to ...identify the most accurate predictor of clinical failure after HIFU.
PATIENTS AND METHODS
Consecutively treated patients who underwent HIFU between October 1997 and July 2006 at two centres (Lyon, France; and Regensburg, Germany) were prospectively maintained within a central database and retrospectively reviewed for this study. Clinical failure was defined as a positive prostate biopsy after treatment, radiographic evidence of lymphatic or bony metastatic disease, or salvage treatment for prostate cancer (surgery, radiation, hormonal therapy or second HIFU). The serum prostate‐specific antigen (PSA) values after HIFU were assessed as a biochemical surrogate of a therapeutic success or failure. PSA threshold values, ‘PSA nadir plus’, PSA velocity, PSA doubling time and the American Society or Therapeutic Radiotherapy and Oncology and Phoenix definition of biochemical failure were all considered. The sensitivity, specificity, positive predictive value and negative predictive value of each biochemical definition for predicting clinical failure were determined.
RESULTS
The data from 285 patients (stage ≤ T2, PSA <15 ng/mL, Gleason score ≤7) were analysed. The median (range) follow‐up was 4.7 (2–10.9) years. The median PSA nadir was 0.13 ng/mL, which occurred at a median of 12.9 weeks after HIFU, and the median PSA at the last follow‐up was 0.76 (1.6–2.7) ng/mL. Clinical failure occurred in 71 patients (25%); 24 due to a positive biopsy and 47 through the use of an additional therapy. Biochemical events that best predicted clinical failure were ‘PSA nadir plus’ values of 1.1–1.3 ng/mL, PSA velocities of <0.3 ng/mL/year and PSA doubling times of 1.25–1.75 years.
CONCLUSION
A new definition of biochemical failure that is specific to patients treated with HIFU therapy is established, i.e. the ‘Stuttgart definition’, the ‘PSA nadir plus 1.2 ng/mL’.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
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