1,124 research outputs found
Nitrogen deposition outweighs climatic variability in driving annual growth rate of canopy beech trees: Evidence from long-term growth reconstruction across a geographic gradient
In this study, we investigated the role of climatic variability and atmospheric nitrogen deposition in driving long-term tree growth in canopy beech trees along a geographic gradient in the montane belt of the Italian peninsula, from the Alps to the southern Apennines. We sampled dominant trees at different developmental stages (from young to mature tree cohorts, with tree ages spanning from 35 to 160 years) and used stem analysis to infer historic reconstruction of tree volume and dominant height. Annual growth volume (G V ) and height (G H ) variability were related to annual variability in model simulated atmospheric nitrogen deposition and site-specific climatic variables, (i.e. mean annual temperature, total annual precipitation, mean growing period temperature, total growing period precipitation, and standard precipitation evapotranspiration index) and atmospheric CO 2 concentration, including tree cambial age among growth predictors. Generalized additive models (GAM), linear mixed-effects models (LMM), and Bayesian regression models (BRM) were independently employed to assess explanatory variables. The main results from our study were as follows: (i) tree age was the main explanatory variable for long-term growth variability; (ii) GAM, LMM, and BRM results consistently indicated climatic variables and CO 2 effects on G V and G H were weak, therefore evidence of recent climatic variability influence on beech annual growth rates was limited in the montane belt of the Italian peninsula; (iii) instead, significant positive nitrogen deposition (N dep ) effects were repeatedly observed in G V and G H ; the positive effects of N dep on canopy height growth rates, which tended to level off at N dep values greater than approximately 1.0 g m â2 y â1 , were interpreted as positive impacts on forest stand above-ground net productivity at the selected study sites
Geoneutrinos in Borexino
This paper describes the Borexino detector and the high-radiopurity studies
and tests that are integral part of the Borexino technology and development.
The application of Borexino to the detection and studies of geoneutrinos is
discussed.Comment: Conference: Neutrino Geophysics Honolulu, Hawaii December 14-16, 200
High sensitivity double beta decay study of 116-Cd and 100-Mo with the BOREXINO Counting Test Facility (CAMEO project)
The unique features (super-low background and large sensitive volume) of the
CTF and BOREXINO set ups are used in the CAMEO project for a high sensitivity
study of 100-Mo and 116-Cd neutrinoless double beta decay. Pilot measurements
with 116-Cd and Monte Carlo simulations show that the sensitivity of the CAMEO
experiment (in terms of the half-life limit for neutrinoless double beta decay)
is (3-5) 10^24 yr with a 1 kg source of 100-Mo (116-Cd, 82-Se, and 150-Nd) and
about 10^26 yr with 65 kg of enriched 116-CdWO_4 crystals placed in the liquid
scintillator of the CTF. The last value corresponds to a limit on the neutrino
mass of less than 0.06 eV. Similarly with 1000 kg of 116-CdWO_4 crystals
located in the BOREXINO apparatus the neutrino mass limit can be pushed down to
m_nu<0.02 eV.Comment: 29 pages, LaTex, 9 eps figure
A large-momentum-transfer matter-wave interferometer to measure the effect of gravity on positronium
This paper reports the study of a new interferometric configuration to measure the effect of gravity on positronium. A MachâZehnder matter-wave interferometer has been designed to operate with single-photon transitions and to transfer high momentum to a 200 eV positronium beam. The work shows the results and methods used to simulate the interferometer and estimate the
operating parameters and the time needed to perform the experiment. It has been estimated that within less than 1 year, the acquisition time is sufficient to achieve a 10% accuracy level in measuring positronium gravitational acceleration, even with a poorly collimated beam, which is significant for theoretical models describing matterâantimatter symmetry. These results pave the way for single photon transition large momentum transfer interferometry with fast atomic beams, which is particularly useful for studies with antimatter and unstable atoms
Efficient positronium laser excitation for antihydrogen production in a magnetic field
Antihydrogen production by charge exchange reaction between Positronium (Ps)
atoms and antiprotons requires an efficient excitation of Ps atoms up to high-n
levels (Rydberg levels). In this study it is assumed that a Ps cloud is
produced within a relatively strong uniform magnetic field (1 Tesla) and with a
relatively high temperature (100 K). Consequently, the structure of energy
levels are deeply modified by Zeeman and motional Stark effects. A two-step
laser light excitation, the first one from ground to n=3 and the second from
this level to a Rydberg level, is proposed and the physics of the problem is
discussed. We derive a simple formula giving the absorption probability with
substantially incoherent laser pulses. A 30% population deposition in high-
states can be reached with feasible lasers suitably tailored in power and
spectral bandwidth.Comment: 18 pages, 4 figures; changed content (with erasing of section 2),
adding a new figure and new reference
Positive Outcomes of a Comprehensive Health Literacy Communication Training for Health Professionals in Three European Countries:A Multi-centre Pre-post Intervention Study
Many professionals have limited knowledge of how to address health literacy; they need a wider range of health literacy competencies to enhance empowerment and person-centred prevention. We evaluated whether: (1) a comprehensive health literacy training increased self-rated competencies of health professionals to address health literacy related problems and support the development of people's autonomy and self-management abilities after training and 6-12 weeks later, (2) professionals were satisfied with the training, (3) outcomes differed for the three participating European countries. Health professionals (N = 106) participated in a multicentre pre-post intervention study in Italy, the Netherlands and Northern Ireland. The 8-hour training-intervention involved health literacy knowledge, the practice of comprehensible communication skills, shared decision-making, and enhancing self-management. Self-rated health literacy competencies and training satisfaction were assessed at baseline, immediately after training and 6-12 weeks later, and analysed by multi-level analysis. Professionals' self-rated health literacy competencies significantly improved following training in all three countries; this increase persisted at 6-12 weeks follow-up. The strongest increase regarded professional's skills to enhance shared-decision making and enabling self-management after training and follow-up respectively. Professionals perceived the training as relevant for practice. Competency increases seemed to be consistent across countries. In three countries, professionals' self-rated health literacy competencies increased following this comprehensive training. These promising findings should be confirmed in a further full effect study. Implementation of this training in European education and health care may improve person-centred communication by professionals and might help to tackle health literacy related problems and to strengthen people's abilities in achieving better health outcomes
Loss and revival of coherence in the interaction between a positron beam and a photon field
We study the interaction between a positron beam in the single-particle regime in an interferometric configuration and a microwave electromagnetic field. We discuss the conditions under which quantum interference can be affected by the field and we outline its possible experimental study in the framework of QUantum interferometry and gravitation
with Positrons and LASers (QUPLAS) experiment
Effects of the lack of forest management on spatiotemporal dynamics of a subalpine Pinus cembra forest
Knowledge about the stand structure and dynamics of subalpine forests is crucial to preserve their multifunctionality. In the present study, we reconstructed the spatiotemporal dynamics of a subalpine Pinus cembra forest in the eastern Italian Alps in response to natural disturbances and forest management. We adopted a concurrent point pattern, dendroecological and growth dominance (GD) analysis. We mapped and measured all trees of Pinus cembra and Larix decidua in a 1 ha plot. We analyzed intra- and interspecific spatial patterns and spatial autocorrelation of tree size and age. We explored establishment dynamics and shifts in competition by analyzing growth suppression/release patterns and GD trends. Results showed a clumped, uneven-aged, multilayered structure where pine was dominant. The synergic action of ecological and human-induced factors is discussed to explain the prevalence of pine over time. Spatial pattern and autocorrelation analyses suggest a different colonization strategy of the two species, in which pine established after small-scale perturbations and experienced a stronger inter- and intra-specific competition. The interruption of tree establishment and shift in GD toward large trees resulting from the lack of forest management are the most important findings of this research. This highlights the importance of an active management to avoid the homogenization of the forest structure that is generally associated with a reduction in biodiversity and protective ability of forests
AEGIS at CERN: Measuring Antihydrogen Fall
The main goal of the AEGIS experiment at the CERN Antiproton Decelerator is
the test of fundamental laws such as the Weak Equivalence Principle (WEP) and
CPT symmetry. In the first phase of AEGIS, a beam of antihydrogen will be
formed whose fall in the gravitational field is measured in a Moire'
deflectometer; this will constitute the first test of the WEP with antimatter.Comment: Presented at the Fifth Meeting on CPT and Lorentz Symmetry,
Bloomington, Indiana, June 28-July 2, 201
Patient Perspectives to Inform a Health Literacy Educational Program:A Systematic Review and Thematic Synthesis of Qualitative Studies
Patient-centred care is tailored to the needs of patients and is necessary for better health outcomes, especially for individuals with limited health literacy (LHL). However, its implementation remains challenging. The key to effectively address patient-centred care is to include perspectives of patients with LHL within the curricula of (future) healthcare providers (HCP). This systematic review aimed to explore and synthesize evidence on the needs, experiences and preferences of patients with LHL and to inform an existing educational framework. We searched three databases: PsychInfo, Medline and Cinahl, and extracted 798 articles. One-hundred and three articles met the inclusion criteria. After data extraction and thematic synthesis, key themes were identified. Patients with LHL and chronic diseases encounter multiple problems in the care process, which are often related to a lack of person-centeredness. Patient perspectives were categorized into four key themes: (1) Support system; (2) Patient self-management; (3) Capacities of HCPs; (4) Barriers in healthcare systems. âCultural sensitivityâ and âeHealthâ were identified as recurring themes. A set of learning outcomes for (future) HCPs was developed based on our findings. The perspectives of patients with LHL provided valuable input for a comprehensive and person-centred educational framework that can enhance the relevance and quality of education for (future) HCPs, and contribute to better person-centred care for patients with LHL
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