2,143 research outputs found
The silicon stable isotope distribution along the GEOVIDE section (GEOTRACES GA-01) of the North Atlantic Ocean
The stable isotope composition of dissolved silicon in seawater (δ30SiDSi) was examined at 10 stations along the GEOVIDE section (GEOTRACES GA-01), spanning the North Atlantic Ocean (40–60∘ N) and Labrador Sea. Variations in δ30SiDSi below 500 m were closely tied to the distribution of water masses. Higher δ30SiDSi values are associated with intermediate and deep water masses of northern Atlantic or Arctic Ocean origin, whilst lower δ30SiDSi values are associated with DSi-rich waters sourced ultimately from the Southern Ocean. Correspondingly, the lowest δ30SiDSi values were observed in the deep and abyssal eastern North Atlantic, where dense southern-sourced waters dominate. The extent to which the spreading of water masses influences the δ30SiDSi distribution is marked clearly by Labrador Sea Water (LSW), whose high δ30SiDSi signature is visible not only within its region of formation within the Labrador and Irminger seas, but also throughout the mid-depth western and eastern North Atlantic Ocean. Both δ30SiDSi and hydrographic parameters document the circulation of LSW into the eastern North Atlantic, where it overlies southern-sourced Lower Deep Water. The GEOVIDE δ30SiDSi distribution thus provides a clear view of the direct interaction between subpolar/polar water masses of northern and southern origin, and allow examination of the extent to which these far-field signals influence the local δ30SiDSi distribution
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Trump-induced anxiety among Latina/os
During the 2016 election, Donald Trump castigated unauthorized immigrants as “murderers and rapists.” During his presidency, he continued the use of this rhetoric, explicitly linking unauthorized migrants to threatening narratives. Here, we consider three questions: Did Donald Trump and his immigration positions serve as an “anxiety trigger” for Latina/os? Are individuals with contextually stigmatized attributes especially sensitive to Trump and his policy proposals? Is Spanish language itself, an attribute negatively stigmatized in the context of the immigration issue, sufficient to increase deportation anxiety? Utilizing survey experiments of Latina/os, we demonstrate that exposure to a Trump immigration cue is sufficient to increase anxiety about deportation. We also demonstrate that stigmatized attributes predict anxiety, but do not moderate the effect of the Trump cue. Lastly, we provide evidence that survey language affects anxiety among Latina/os. In Studies 1 (n = 736) and 2 (n = 1,040), we show that exposure to information about Trump’s immigration agenda significantly increases reports about deportation anxiety. In Study 3 (n = 1,734), we show that the Trump exposure condition induces heightened anxiety but that Latina/o attributes (language proficiency and use, immigration status, assessed phenotype) and identity strength have an independent effect on deportation anxiety. In Study 4 (n = 775), we randomized bilingual respondents into Spanish or English language survey protocols and found that comparable bilinguals exposed to Spanish language report higher levels of anxiety compared to English-language survey takers
Tuning the electrical conductivity of nanotube-encapsulated metallocene wires
We analyze a new family of carbon nanotube-based molecular wires, formed by
encapsulating metallocene molecules inside the nanotubes. Our simulations, that
are based on a combination of non-equilibrium Green function techniques and
density functional theory, indicate that these wires can be engineered to
exhibit desirable magnetotransport effects for use in spintronics devices. The
proposed structures should also be resilient to room-temperature fluctuations,
and are expected to have a high yield.Comment: 4 pages, 6 figures. Accepted in Physical Review Letter
Dealing with the uncertainty of technical changes in the CORINE Land Cover dataset: The Portuguese approach
Land Use and Land Cover (LULC) datasets are widely used across disciplines, with many users demanding more
and better information. Understanding the uncertainties and errors associated to the main LULC datasets is a
required step to facilitate their correct use, as well as to identify what could be improved in the future production
of these products. CORINE Land Cover is probably the most well-known and used LULC dataset in Europe,
especially valuable for the rich time-series that it provides. Despite being produced through a change mapping
first approach, which tries to avoid technical errors and uncertainties in the temporal analysis of LULC changes,
the Copernicus Land Monitoring Service distributes status layers of CORINE (CSL), which are not valid for change
analysis because of their associated errors and uncertainties. The CORINE layers of changes (CHA) remove a lot
of these issues, but do not meet the needs of many users. In Portugal, the national authority in charge of producing CORINE, the DGT, has implemented a backdating approach to produce consistent CSL layers that allow
change analysis with low levels of uncertainty. Throughout this paper, we evaluate the changes that can be
analyzed through all available CORINE layers in Portugal: Copernicus CSL layers; the national DGT CSL layers;
and CHA layers. To this end, we aim to assess what type of changes can be studied through each type of layer,
their associated sources of uncertainty and the relevance and utility of the Portuguese backdating approach to
produce a consistent time-series of LULC maps. The results prove how the Portuguese CORINE layers distributed
by the Copernicus Land Monitoring Service contain important sources of uncertainty, which however have been
removed through the national backdating methodology. This methodology can be therefore exported for the
production of CORINE in other European countries.info:eu-repo/semantics/publishedVersio
Estudio de la marcha en pacientes tratados ortopédicamente de fractura unilateral del calcáneo
Veinticinco pacientes afectos de fractura unilateral desplazada articular de calcá-
neo fueron tratados mediante inmovilización con yeso, siendo los resultados a los 6 años (rango:
3-10), excelentes en 5 pacientes, buenos en 4, regulares en 7 y malos en 9. De este grupo se excluyeron
los afectos de patología local o general asociada, siendo útiles para el estudio de la marcha
12 pacientes a los que se les hizo deambular sobre plataformas dinamométricas para registrar
la fuerza de reacción al suelo, demostrando una disminución de la fuerza vertical de apoyo y
despegue (F1 y F3) y un aumento estadísticamente significativo del tiempo de apoyo total durante
la marcha. Abogamos por la restitución anatómica del calcáneo como medio para mejorar la
capacidad funcional del paciente.Twenty-five patients with unilateral displaced joint calcaneus fracture were treated
by cast being the results after 6 years (range: 3-10), excellent in 5 patients, good in 4 patients,
poor in 7 and bad in 9. We excluded for the study the patients with associated local or general
pathology being useful for our study 12 patients. These patients walked on a dynamometric platform
in order to analyse floor reaction forces, proving a diminuí ion of vertical support and takeoff
forces (Fl and F2), and statistically significant a increase of total support phase during gait
Estudio comparativo de la fijación con o sin cemento en Prótesis Total de Rodilla
Revisamos retrospectivamente una serie de 86 pacientes portadores de 110
prótesis totales modulares de rodilla colocadas como tratamiento de la gonartrosis. Se analizan
los resultados obtenidos en los pacientes a los que se le realizó una fijación híbrida cementada
(componente femoral no cementado y componente tibial y patelar cementado) respecto a los
que se le realizó una prótesis de anclaje biológico sin ningún tipo de cementación. El análisis
de la función clínica, movilidad de la rodilla, estudio radiológico y complicaciones de ambas series
no demuestran diferencias significativas entre ambos grupos con un periodo de seguimiento
de 45 meses (r=12-60).We have retrospectively review 86 patients with 110 total knee arthroplasty for
the treatment of osteoarthrosis. We have analyzed the results obtained in a group of patients
with partial fixation with cement and another group fixated without any cement. Clinical and
radiological results and complications in both groups were similar without significant differences
with an average follow-up of 45 months (12-60)
Mindfulness Training Improves Quality of Life and Reduces Depression and Anxiety Symptoms Among Police Officers: Results From the POLICE Study—A Multicenter Randomized Controlled Trial
Background: Police officers'' high-stress levels and its deleterious consequences are raising awareness to an epidemic of mental health problems and quality of life (QoL) impairment. There is a growing evidence that mindfulness-based interventions are efficacious to promote mental health and well-being among high-stress occupations. Methods: The POLICE study is a multicenter randomized controlled trial (RCT) with three assessment points (baseline, post-intervention, and 6-month follow-up) where police officers were randomized to mindfulness-based health promotion (MBHP) (n = 88) or a waiting list (n = 82). This article focuses on QoL, depression and anxiety symptoms, and religiosity outcomes. Mechanisms of change and MBHP feasibility were evaluated. Results: Significant group × time interaction was found for QoL, depression and anxiety symptoms, and non-organizational religiosity. Between-group analysis showed that MBHP group exhibited greater improvements in QoL, and depression and anxiety symptoms at both post-intervention (QoL d = 0.69 to 1.01; depression d = 0.97; anxiety d = 0.73) and 6-month follow-up (QoL d = 0.41 to 0.74; depression d = 0.60; anxiety d = 0.51), in addition to increasing non-organizational religiosity at post-intervention (d = 0.31). Changes on self-compassion mediated the relationship between group and pre-to-post changes for all QoL domains and facets. Group effect on QoL overall health facet at post-intervention was moderated by mindfulness trait and spirituality changes. Conclusion: MBHP is feasible and efficacious to improve QoL, and depression and anxiety symptoms among Brazilian officers. Results were maintained after 6 months. MBHP increased non-organizational religiosity, although the effect was not sustained 6 months later. To our knowledge, this is the first mindfulness-based intervention RCT to empirically demonstrate these effects among police officers. Self-compassion, mindfulness trait, and spirituality mechanisms of change are examined. Clinical Trial Registration: www.ClinicalTrials.gov. identifier: NCT03114605.
Exact scaling in the expansion-modification system
This work is devoted to the study of the scaling, and the consequent
power-law behavior, of the correlation function in a mutation-replication model
known as the expansion-modification system. The latter is a biology inspired
random substitution model for the genome evolution, which is defined on a
binary alphabet and depends on a parameter interpreted as a \emph{mutation
probability}. We prove that the time-evolution of this system is such that any
initial measure converges towards a unique stationary one exhibiting decay of
correlations not slower than a power-law. We then prove, for a significant
range of mutation probabilities, that the decay of correlations indeed follows
a power-law with scaling exponent smoothly depending on the mutation
probability. Finally we put forward an argument which allows us to give a
closed expression for the corresponding scaling exponent for all the values of
the mutation probability. Such a scaling exponent turns out to be a piecewise
smooth function of the parameter.Comment: 22 pages, 2 figure
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