12,367 research outputs found
The Economic Effects of Democratic Participation
Considerable concern has been expressed in recent years about declines in voter participation rates in the United States and in several other major democratic countries. Some feel low participation rates introduce a “class bias” into the political process and thereby worsen the outcomes from it. Little empirical work exists, however, that measures the effects of lower participation on the welfare of a country. This paper begins to fill this void. It presents cross-national evidence that high levels of democratic participation are associated with more equal distributions of income. The paper’s results also imply, however, that this reduction in income inequality comes at a cost. High participation rates are related to larger government sectors which in turn lead to slower economic growth. We also present evidence of the “capture” of government by upper income groups in Latin and Central American countries.
Detrital-zircon geochronology and provenance of the Ocloyic synorogenic clastic wedge, and Ordovician accretion of the Argentine Precordillera terrane
The Precordillera terrane in northwestern Argentina is interpreted to be anexotic (Laurentian) continental fragment that was accreted to western Gondwanaduring the Ordovician. One prominent manifestation of the subductionand collision process is a Middle?Upper Ordovician clastic wedge, which overliesa passive-margin carbonate-platform succession in the Precordillera. U/Pbages of detrital zircons from sandstones within the clastic wedge, as well as zirconsfrom clasts within conglomerates, provide documentation for the compositionof the sediment provenance. The ages of detrital zircons are consistentvertically through the succession, as well as laterally along and across strike ofthe Precordillera, indicating a single, persistent sediment source throughoutdeposition of the clastic wedge. The dominant mode (~1350?1000 Ma) of thedetrital-zircon ages corresponds to the ages of basement rocks in the WesternSierras Pampeanas along the eastern side of the Precordillera. A secondarymode (1500?1350 Ma) corresponds in age to the Granite-Rhyolite province ofLaurentia, an age range which is not known in ages of basement rocks of theWestern Sierras Pampeanas; however, detritus from Granite-Rhyolite-age rocksin the basement of the Precordillera was available through recycling of synriftand passive-margin cover strata. Igneous clasts in the conglomerates haveages (647?614 Ma) that correspond to the ages of minor synrift igneous rocks inthe nearby basement massifs; the same ages are represented in a minor mode(~750?570 Ma) of detrital-zircon ages. A quartzite clast in a conglomerate, aswell as parts of the population of detrital zircons, indicates the importanceof a source in the metasedimentary cover of the leading edge of the Precordillera.The Famatina continental-margin magmatic arc reflects pre-collisionsubduction of Precordillera lithosphere beneath the western Gondwana margin;however, no detrital zircons have ages that correspond to Famatina arcmagmatism, indicating that sedimentary detritus from the arc may have beentrapped in a forearc basin and did not reach the foreland. The indicators ofsedimentary provenance for the foreland deposits are consistent with subductionof the Precordillera beneath western Gondwana, imbrication of basementrocks from either the Precordillera or Gondwana into an accretionary complex,and recycling of deformed Precordillera cover rocks.Fil: Thomas, William A.. Geological Survey of Alabama; Estados UnidosFil: Astini, Ricardo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Mueller, Paul A.. Florida State University; Estados UnidosFil: McClelland, William C.. University of Iowa; Estados Unido
Social vs. practical problems in attaining a colonoscopy: Different patient profiles?
Background: Colonoscopy is an effective procedure for identifying precancerous polyps and cancerous lesions, but it is unlike other cancer screening tools in that it requires sedation and thus assistance from at least one other individual. The intent of this paper was to identify logistical problems in completing the colonoscopy and to examine their relationships with sociodemographic characteristics.
Methods: All eligible patients (n = 2500) from two academic-affiliated colonoscopy centers (one free standing, one hospital-based) were invited to participate in an onsite, pre-colonoscopy survey; patients agreeing to participate (n = 1841, RR = 73.6%) received a $5.00 gift card. Multiple correspondence analysis (MCA) was used to identify the underlying dimensional structure of the problems. Bivariate statistics were performed to compare demographic variables and health literacy levels among patients reporting problems. Multivariate logistic regression with a backwards conditional solution was used to determine the demographic variables independently associated with problems.
Results: Multiple correspondence analyses indicated two dimensions of problems (social and practical). Using logistic regression, social problems (e.g., finding someone to accompany the patient) were associated with not living in the same home as the driver, not working due to disability, and younger age. Practical problems (e.g., making an appointment) were associated with “other” minority race, poorer health, lower health literacy, and younger age.
Conclusion: Patients experience different problems completing the colonoscopy based on socio-demographics. Particularly at risk are patients who find it difficult to navigate the system, are of younger age, or who may have smaller social networks
Non-random dispersal in the butterfly Maniola jurtina: implications for metapopulation models
The dispersal patterns of animals are important in metapopulation ecology because they affect the dynamics and survival of populations. Theoretical models assume random dispersal but little is known in practice about the dispersal behaviour of individual animals or the strategy by which dispersers locate distant habitat patches. In the present study, we released individual meadow brown butterflies (Maniola jurtina) in a non-habitat and investigated their ability to return to a suitable habitat. The results provided three reasons for supposing that meadow brown butterflies do not seek habitat by means of random flight. First, when released within the range of their normal dispersal distances, the butterflies orientated towards suitable habitat at a higher rate than expected at random. Second, when released at larger distances from their habitat, they used a non-random, systematic, search strategy in which they flew in loops around the release point and returned periodically to it. Third, butterflies returned to a familiar habitat patch rather than a non-familiar one when given a choice. If dispersers actively orientate towards or search systematically for distant habitat, this may be problematic for existing metapopulation models, including models of the evolution of dispersal rates in metapopulations
Authenticated and Secure Automotive Service Discovery with DNSSEC and DANE
Automotive softwarization is progressing and future cars are expected to
operate a Service-Oriented Architecture on multipurpose compute units, which
are interconnected via a high-speed Ethernet backbone. The AUTOSAR architecture
foresees a universal middleware called SOME/IP that provides the service
primitives, interfaces, and application protocols on top of Ethernet and IP.
SOME/IP lacks a robust security architecture, even though security is an
essential in future Internet-connected vehicles. In this paper, we augment the
SOME/IP service discovery with an authentication and certificate management
scheme based on DNSSEC and DANE. We argue that the deployment of well-proven,
widely tested standard protocols should serve as an appropriate basis for a
robust and reliable security infrastructure in cars. Our solution enables
on-demand service authentication in offline scenarios, easy online updates, and
remains free of attestation collisions. We evaluate our extension of the common
vsomeip stack and find performance values that fully comply with car
operations
Cedratvirus lausannensis - digging into Pithoviridae diversity.
Amoeba-infecting viruses have raised scientists' interest due to their novel particle morphologies, their large genome size and their genomic content challenging previously established dogma. We report here the discovery and the characterization of Cedratvirus lausannensis, a novel member of the Megavirales, with a 0.75-1 µm long amphora-shaped particle closed by two striped plugs. Among numerous host cell types tested, the virus replicates only in Acanthamoeba castellanii leading to host cell lysis within 24 h. C. lausannensis was resistant to ethanol, hydrogen peroxide and heating treatments. Like 30 000-year-old Pithovirus sibericum, C. lausannensis enters by phagocytosis, releases its genetic content by fusion of the internal membrane with the inclusion membrane and replicates in intracytoplasmic viral factories. The genome encodes 643 proteins that confirmed the grouping of C. lausannensis with Cedratvirus A11 as phylogenetically distant members of the family Pithoviridae. The 575,161 bp AT-rich genome is essentially devoid of the numerous repeats harbored by Pithovirus, suggesting that these non-coding repetitions might be due to a selfish element rather than particular characteristics of the Pithoviridae family. The discovery of C. lausannensis confirms the contemporary worldwide distribution of Pithoviridae members and the characterization of its genome paves the way to better understand their evolution
ExploreNEOs VIII: Dormant Short-Period Comets in the Near-Earth Asteroid Population
We perform a search for dormant comets, asteroidal objects of cometary
origin, in the near-Earth asteroid (NEA) population based on dynamical and
physical considerations. Our study is based on albedos derived within the
ExploreNEOs program and is extended by adding data from NEOWISE and the Akari
asteroid catalog. We use a statistical approach to identify asteroids on orbits
that resemble those of short-period near-Earth comets using the Tisserand
parameter with respect to Jupiter, the aphelion distance, and the minimum
orbital intersection distance with respect to Jupiter. From the sample of NEAs
on comet-like orbits, we select those with a geometric albedo
as dormant comet candidates, and find that only 50% of NEAs on comet-like
orbits also have comet-like albedos. We identify a total of 23 NEAs from our
sample that are likely to be dormant short-period near-Earth comets and, based
on a de-biasing procedure applied to the cryogenic NEOWISE survey, estimate
both magnitude-limited and size-limited fractions of the NEA population that
are dormant short-period comets. We find that 0.3-3.3% of the NEA population
with , and % of the population with diameters km, are dormant short-period near-Earth comets.Comment: 23 pages, 2 figures, 2 tables; accepted for publication in A
Isotonitazene: Fatal intoxication in three cases involving this unreported novel psychoactive substance in Switzerland.
The paper describes the first three deaths reported in Europe involved in isotonitazene consumption, a potent benzimidazole derivate opioid consumed in the recreational drug scene. Isotonitazene powder and purity determination was performed on the sample collected in the first death scene by NMR, HRMS, GC-FTIR, ATR-FTIR and GC-MS. Isotonitazene purity was determined by GC-MS analysis and proton NMR, and was defined to be above 95 % and 98 %, respectively. Quantification of isotonitazene in biological samples was performed using a targeted analysis based on SPE extraction and ultra-high performance liquid chromatography tandem mass spectrometry. The isotonitazene median concentration in femoral whole blood was 1.20ng/mL. Isotonitazene concentration in hair was similar or even lower compared to that seen in fentanyl abusers. Isotonitazene distribution in tissues converges in the brain, lungs and heart, respectively. Surprisingly, isotonitazene concentration in liver is the lowest measured for all tissues and fluids analyzed. Based on circumstantial evidence, autopsy findings and the results of the toxicological analysis, the medical examiner concluded that the cause of all three deaths was an acute intoxication with isotonitazene. Since isotonitazene toxic concentration levels are very low, the consumption of this new psychoactive drug is a real hazard for human health
Using Machine Learning to Generate a Core Set of Echocardiographic Indices for Pediatric Research: A Sub-study in the PCS2 Cohort
With a multitude of echocardiographic (echo) parameters at a clinician’s disposal and clinical efficiency paramount, determining the most reliable and relevant pediatric echo parameters remains challenging. Using machine learning (ML), clinical relevance, and inter/intra-rater reliability, we aimed to identify a core set of echo parameters from the PCS2 cohort of childhood cancer survivors and healthy controls to guide pediatric research and clinical care. A standard set of 94 echocardiographic parameters were chosen and screened for missing variation, linear combinations, and high correlations. A hierarchical cluster analysis using Ward’s method was performed on the remaining variables to produce a clustering dendrogram. Thereafter, inter- and intra-rater reliability analyses were conducted using intraclass correlation coefficients (ICC) and Bland-Altman (B-A) plots. Using highly reliable (\u3e0.65 ICC) and available (\u3e80% scored) parameters, five pediatric cardiologists ranked each parameter within cluster for clinical relevance. Of the 61 echo parameters selected for the dendrogram, only 54 were scored due to feasibility of sonographer acquisition. ≥73% of all scored parameters had good (0.60-0.74) or excellent (≥0.75) ICC in the inter- and intra-rater analyses. Mean within cluster ranks were assigned per parameter to identify a core set of 10, and minimal set of 5 parameters: ejection fraction (EF), mitral valve E/E’, tissue doppler interventricular septum valve S-velocity, average global longitudinal strain, and LV end diastolic diameter. Using clustering analysis, clinical relevance rankings, and reliability we have identified 10 core and 5 minimal echo indices to guide further pediatric echocardiographic research and clinical care
Modeling associations between genetic markers using Bayesian networks
Motivation: Understanding the patterns of association between polymorphisms at different loci in a population (linkage disequilibrium, LD) is of fundamental importance in various genetic studies. Many coefficients were proposed for measuring the degree of LD, but they provide only a static view of the current LD structure. Generative models (GMs) were proposed to go beyond these measures, giving not only a description of the actual LD structure but also a tool to help understanding the process that generated such structure. GMs based in coalescent theory have been the most appealing because they link LD to evolutionary factors. Nevertheless, the inference and parameter estimation of such models is still computationally challenging
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