The biological pump transports organic carbon produced by photosynthesis to the meso- and bathypelagic zones, the latter removing carbon from exchanging with the atmosphere over centennial time ...scales. Organisms living in both zones are supported by a passive flux of particles, and carbon transported to the deep-sea through vertical zooplankton migrations. Here we report globally-coherent positive relationships between zooplankton biomass in the epi-, meso-, and bathypelagic layers and average net primary production (NPP). We do so based on a global assessment of available deep-sea zooplankton biomass data and large-scale estimates of average NPP. The relationships obtained imply that increased NPP leads to enhanced transference of organic carbon to the deep ocean. Estimated remineralization from respiration rates by deep-sea zooplankton requires a minimum supply of 0.44 Pg C y
transported into the bathypelagic ocean, comparable to the passive carbon sequestration. We suggest that the global coupling between NPP and bathypelagic zooplankton biomass must be also supported by an active transport mechanism associated to vertical zooplankton migration.
Fast-timing spectroscopy at ISOLDE Fraile, L M
Journal of physics. G, Nuclear and particle physics,
09/2017, Letnik:
44, Številka:
9
Journal Article
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The advanced time-delayed β γ γ (t) method has been used at ISOLDE since the relocation of the facility from the synchrocyclotron to the CERN proton synchrotron booster, a quarter of a century ago. ...The method was designed for precision measurements with low-intensity beams, achieving good efficiency and excellent time resolution with a compact setup. Over this time the technique has evolved to cope with the challenge of measuring lifetimes of complex level schemes of increasingly exotic nuclei populated in β decay. The ISOLDE facility provides unsurpassed opportunities to study many regions of the nuclide chart. The physics case encompasses topics of interest across the nuclide chart, including the evolution of shell structure around neutron shell and subshell closures such as N = 20, N = 40 and N = 50, shape coexistence, and octupole correlations in heavy nuclei. The recently commissioned ISOLDE decay station provides enhanced capabilities that will be fully exploited with the increased beam intensities available at the upcoming HIE-ISOLDE facility.
To score systemic activity at diagnosis and correlate baseline activity with survival in a large cohort of patients with primary Sjögren syndrome (SS).
We include 1045 consecutive patients who ...fulfilled the 2002 classification criteria for primary SS. The clinical and immunological characteristics and level of activity (EULAR-SS Disease Activity Index (ESSDAI) scores) were assessed at diagnosis as predictors of death using Cox proportional hazards regression analysis adjusted for age at diagnosis. The risk of death was calculated at diagnosis according to four different predictive models.
After a mean follow-up of 117 months, 115 (11%) patients died. The adjusted standardised mortality ratio for the total cohort was 4.66 (95% CI 3.85 to 5.60), and survival rates at 5, 10, 20 and 30 years were 96%, 90%, 81% and 60%, respectively. The main baseline factors associated with overall mortality in the multivariate analysis were male gender, cryoglobulins and low C4 levels. Baseline activity in the constitutional, pulmonary and biological domains was associated with a higher risk of death. High activity in at least one ESSDAI domain (HR 2.14), a baseline ESSDAI score ≥14 (HR 1.85) and more than one laboratory predictive marker (lymphopenia, anti-La, monoclonal gammopathy, low C3, low C4 and/or cryoglobulins) (HR 2.82) were associated with overall mortality; these HRs increased threefold to 10-fold when the analysis was restricted to mortality associated with systemic disease.
Patients with primary SS, who present at diagnosis with high systemic activity (ESSDAI ≥14) and/or predictive immunological markers (especially those with more than one), are at higher risk of death.
We report results on the long-term variation of the neutron counting rate at the Canfranc Underground Laboratory, of importance for several low-background experiments installed there, including ...rare-event searches. The measurement campaign was performed employing the High Efficiency Neutron Spectrometry Array (HENSA) mounted in Hall A and lasted 412 live days. The present study is the first long-term measurement of the neutron rate with sensitivity over a wide range of neutron energies (from thermal up to 0.1 GeV and beyond) performed in any underground laboratory so far. Data on the environmental variables inside the experimental hall (radon concentration, air temperature, air pressure and humidity) were also acquired during all the measurement campaign. We have investigated for the first time the evolution of the neutron rate for different energies of the neutrons and its correlation with the ambient variables.
The 8B+64Zn reaction at 38.5 MeV has been studied at HIE-ISOLDE CERN to investigate proton halo effect on the reaction dynamics. For the first time it was used the only existing post-accelerated 8B ...beam. The measured elastic scattering angular distribution showed a small suppression of the Coulomb-nuclear interference peak, opposite to what observed for the one-neutron halo nucleus 11Be on the same target where a large suppression was observed instead. Inclusive angular and energy distributions of breakup fragments were also measured showing that, both, elastic and non-elastic breakup contribute. The presence of the additional Coulomb interactions halo-core and halo-target in 8B makes the reaction dynamics in this proton-halo nucleus different than the neutron-halo case.
When a heavy atomic nucleus splits (fission), the resulting fragments are observed to emerge spinning
; this phenomenon has been a mystery in nuclear physics for over 40 years
. The internal ...generation of typically six or seven units of angular momentum in each fragment is particularly puzzling for systems that start with zero, or almost zero, spin. There are currently no experimental observations that enable decisive discrimination between the many competing theories for the mechanism that generates the angular momentum
. Nevertheless, the consensus is that excitation of collective vibrational modes generates the intrinsic spin before the nucleus splits (pre-scission). Here we show that there is no significant correlation between the spins of the fragment partners, which leads us to conclude that angular momentum in fission is actually generated after the nucleus splits (post-scission). We present comprehensive data showing that the average spin is strongly mass-dependent, varying in saw-tooth distributions. We observe no notable dependence of fragment spin on the mass or charge of the partner nucleus, confirming the uncorrelated post-scission nature of the spin mechanism. To explain these observations, we propose that the collective motion of nucleons in the ruptured neck of the fissioning system generates two independent torques, analogous to the snapping of an elastic band. A parameterization based on occupation of angular momentum states according to statistical theory describes the full range of experimental data well. This insight into the role of spin in nuclear fission is not only important for the fundamental understanding and theoretical description of fission, but also has consequences for the γ-ray heating problem in nuclear reactors
, for the study of the structure of neutron-rich isotopes
, and for the synthesis and stability of super-heavy elements
.
Gaia Early Data Release 3 Lindegren, L.; Klioner, S. A.; Hernández, J. ...
Astronomy and astrophysics (Berlin),
05/2021, Letnik:
649
Journal Article
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Context. Gaia
Early Data Release 3 (
Gaia
EDR3) contains results for 1.812 billion sources in the magnitude range
G
= 3–21 based on observations collected by the European Space Agency
Gaia
satellite ...during the first 34 months of its operational phase.
Aims.
We describe the input data, the models, and the processing used for the astrometric content of
Gaia
EDR3, as well as the validation of these results performed within the astrometry task.
Methods.
The processing broadly followed the same procedures as for
Gaia
DR2, but with significant improvements to the modelling of observations. For the first time in the
Gaia
data processing, colour-dependent calibrations of the line- and point-spread functions have been used for sources with well-determined colours from DR2. In the astrometric processing these sources obtained five-parameter solutions, whereas other sources were processed using a special calibration that allowed a pseudocolour to be estimated as the sixth astrometric parameter. Compared with DR2, the astrometric calibration models have been extended, and the spin-related distortion model includes a self-consistent determination of basic-angle variations, improving the global parallax zero point.
Results. Gaia
EDR3 gives full astrometric data (positions at epoch J2016.0, parallaxes, and proper motions) for 1.468 billion sources (585 millionwith five-parameter solutions, 882 million with six parameters), and mean positions at J2016.0 for an additional 344 million.Solutions with five parameters are generally more accurate than six-parameter solutions, and are available for 93% of the sources brighter than the 17th magnitude. The median uncertainty in parallax and annual proper motion is 0.02–0.03 mas at magnitude
G
= 9–14, and around 0.5 mas at
G
= 20. Extensive characterisation of the statistical properties of the solutions is provided, including the estimated angular power spectrum of parallax bias from the quasars.
Even mass neutron-rich niobium isotopes are among the principal contributors to the reactor antineutrino energy spectrum. They are also among the most challenging to measure due to the refractory ...nature of niobium, and because they exhibit isomeric states lying very close in energy. The β-intensity distributions of 100gs,100mNb and 102gs,102mNb β decays have been determined using the total absorption γ-ray spectroscopy technique. The measurements were performed at the upgraded Ion Guide Isotope Separator On-Line facility at the University of Jyväskylä. Here, the double Penning trap system JYFLTRAP was employed to disentangle the β decay of the isomeric states. The new data obtained in this challenging measurement have a large impact in antineutrino summation calculations. As a result, for the first time the discrepancy between the summation model and the reactor antineutrino measurements in the region of the shape distortion has been reduced.
AimsPeople who have schizophrenia die earlier from somatic diseases than do people in the general population, but information about cardiovascular deaths in people who have schizophrenia is limited. ...We analysed mortality in all age groups of people with schizophrenia by specific cardiovascular diseases (CVDs), focusing on five CVD diagnoses: coronary heart disease, acute myocardial infarction, cerebrovascular disease, heart failure and cardiac arrhythmias. We also compared hospital admissions for CVDs in people who had schizophrenia with hospital admissions for CVDs in the general population.
This national register study of 10 631 817 people in Sweden included 46 911 people who were admitted to the hospital for schizophrenia between 1 January 1987 and 31 December 2010. Information from national registers was used to identify people who had schizophrenia and obtain data about mortality, causes of death, medical diagnoses and hospitalisations.
CVDs were the leading cause of death in people who had schizophrenia (5245 deaths), and CVDs caused more excess deaths than suicide. The mean age of CVD death was 10 years lower for people who had schizophrenia (70.5 years) than the general population (80.7 years). The mortality rate ratio (MRR) for CVDs in all people who had schizophrenia was 2.80 (95% confidence interval (CI) 2.73-2.88). In people aged 15-59 years who had schizophrenia, the MRR for CVDs was 6.16 (95% CI 5.79-6.54). In all people who had schizophrenia, the MRR for coronary heart disease was 2.83 (95% CI 2.73-2.94); acute myocardial infarction, 2.62 (95% CI 2.49-2.75); cerebrovascular disease, 2.4 (95% CI 2.25-2.55); heart failure, 3.25 (95% CI 2.94-3.6); and cardiac arrhythmias, 2.06 (95% CI 1.75-2.43). Hospital admissions for coronary heart disease were less frequent in people who had schizophrenia than in the general population (admission rate ratio, 0.88 (95% CI 0.83-0.94). In all age groups, survival after hospital admission for CVD was lower in people who had schizophrenia than in the general population.
People who had schizophrenia died 10 years earlier from CVDs than did people in the general population. For all five CVD diagnoses, mortality risk was higher for those with schizophrenia than those in the general population. Survival after hospitalisation for CVDs in people who had schizophrenia was comparable with that of people in the general population who were several decades older.
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