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A gyrokinetic Coulomb collision operator is derived, which is particularly useful to describe the plasma dynamics at the periphery region of magnetic confinement fusion devices. The derived operator is able to describe collisions occurring in distribution functions arbitrarily far from equilibrium with variations on spatial scales at and below the particle Larmor radius. A multipole expansion of the Rosenbluth potentials is used in order to derive the dependence of the full Coulomb collision operator on the particle gyroangle. The full Coulomb collision operator is then expressed in gyrocentre phase-space coordinates, and a closed formula for its gyroaverage in terms of the moments of the gyrocentre distribution function in a form ready to be numerically implemented is provided. Furthermore, the collision operator is projected onto a Hermite–Laguerre velocity space polynomial basis and expansions in the small electron-to-ion mass ratio are provided.
In Canada, recreational use of cannabis was legalized in October 2018. This policy change along with recent publications evaluating the efficacy of cannabis for the medical treatment of epilepsy and media awareness about its use have increased the public interest about this agent. The Canadian League Against Epilepsy Medical Therapeutics Committee, along with a multidisciplinary group of experts and Canadian Epilepsy Alliance representatives, has developed a position statement about the use of medical cannabis for epilepsy. This article addresses the current Canadian legal framework, recent publications about its efficacy and safety profile, and our understanding of the clinical issues that should be considered when contemplating cannabis use for medical purposes.
In the 2015 review paper ‘Petawatt Class Lasers Worldwide’ a comprehensive overview of the current status of high-power facilities of
was presented. This was largely based on facility specifications, with some description of their uses, for instance in fundamental ultra-high-intensity interactions, secondary source generation, and inertial confinement fusion (ICF). With the 2018 Nobel Prize in Physics being awarded to Professors Donna Strickland and Gerard Mourou for the development of the technique of chirped pulse amplification (CPA), which made these lasers possible, we celebrate by providing a comprehensive update of the current status of ultra-high-power lasers and demonstrate how the technology has developed. We are now in the era of multi-petawatt facilities coming online, with 100 PW lasers being proposed and even under construction. In addition to this there is a pull towards development of industrial and multi-disciplinary applications, which demands much higher repetition rates, delivering high-average powers with higher efficiencies and the use of alternative wavelengths: mid-IR facilities. So apart from a comprehensive update of the current global status, we want to look at what technologies are to be deployed to get to these new regimes, and some of the critical issues facing their development.
There is a long history of exploitation of the South American river turtle Podocnemis expansa. Conservation efforts for this species started in the 1960s but best practices were not established, and population trends and the number of nesting females protected remained unknown. In 2014 we formed a working group to discuss conservation strategies and to compile population data across the species’ range. We analysed the spatial pattern of its abundance in relation to human and natural factors using multiple regression analyses. We found that > 85 conservation programmes are protecting 147,000 nesting females, primarily in Brazil. The top six sites harbour > 100,000 females and should be prioritized for conservation action. Abundance declines with latitude and we found no evidence of human pressure on current turtle abundance patterns. It is presently not possible to estimate the global population trend because the species is not monitored continuously across the Amazon basin. The number of females is increasing at some localities and decreasing at others. However, the current size of the protected population is well below the historical population size estimated from past levels of human consumption, which demonstrates the need for concerted global conservation action. The data and management recommendations compiled here provide the basis for a regional monitoring programme among South American countries.
The dynamics of electron-plasma waves is described at arbitrary collisionality by considering the full Coulomb collision operator. The description is based on a Hermite–Laguerre decomposition of the velocity dependence of the electron distribution function. The damping rate, frequency and eigenmode spectrum of electron-plasma waves are found as functions of the collision frequency and wavelength. A comparison is made between the collisionless Landau damping limit, the Lenard–Bernstein and Dougherty collision operators and the electron–ion collision operator, finding large deviations in the damping rates and eigenmode spectra. A purely damped entropy mode, characteristic of a plasma where pitch-angle scattering effects are dominant with respect to collisionless effects, is shown to emerge numerically, and its dispersion relation is analytically derived. It is shown that such a mode is absent when simplified collision operators are used, and that like-particle collisions strongly influence the damping rate of the entropy mode.
Debates over whether transnational and international legal institutions are fair, effective, or legitimate responses to corruption of local public officials have an important empirical dimension. We use case studies to examine whether foreign legal institutions serve as fair, effective, and legitimate complements to local anticorruption institutions. We refer to this set of claims as the “institutional complementarity theory.” The first case study centers on proceedings concerning bribes paid by subsidiaries of Siemens AG, a German company, to obtain and retain a contract to provide national identity cards for the Argentine government. The second case study examines events stemming from overbilling in the construction of a courthouse in Brazil. Analysis of these cases suggests that the institutional complementary theory is credible. At the same time, the findings suggest that local institutions have greater potential, and foreign institutions have more limited potential, than the theory assumes.
Individuals with bipolar disorder (BD) show aberrant brain activation patterns during reward and loss anticipation. We examined for the first time longitudinal changes in brain activation during win and loss anticipation to identify trait markers of aberrant anticipatory processing in BD.
Thirty-four euthymic and depressed individuals with BD-I and 17 healthy controls (HC) were scanned using functional magnetic resonance imaging twice 6 months apart during a reward task.
HC, but not individuals with BD, showed longitudinal reductions in the right lateral occipital cortex (RLOC) activation during processing of cues predicting possible money loss (p-corrected <0.05). This result was not affected by psychotropic medication, mood state or the changes in depression/mania severity between the two scans in BD. Elevated symptoms of subthreshold hypo/mania at baseline predicted more aberrant longitudinal patterns of RLOC activation explaining 12.5% of variance in individuals with BD.
Increased activation in occipital cortex during negative outcome anticipation may be related to elevated negative emotional arousal during anticipatory cue processing. One interpretation is that, unlike HC, individuals with BD were not able to learn at baseline that monetary losses were smaller than monetary gains and were not able to reduce emotional arousal for negative cues 6 months later. Future research in BD should examine how modulating occipital cortical activation affects learning from experience in individuals with BD.
Trends in structural and chemical leaf traits along a chronosequence of semi-evergreen tropical forest and their correlation with litter production and decomposition and associated carbon (C) and nitrogen (N) fluxes were assessed. Leaves of 15 dominant species in each plot were collected to measure leaf area, specific leaf area (SLA), C and N concentration and C:N ratio. Litterfall was measured and litter decomposition experiments were set up in 16 experimental plots in a chronosequence of secondary and mature forest. All five leaf traits combined discriminated the secondary forests from mature forest. SLA, N and C:N were significantly correlated to litter decomposition rates. Litter decomposition was significantly slower in mature forest compared with secondary forests. The N concentration of litter was lowest during the dry season, when litterfall was highest. N concentration in fresh leaves was higher than in litter, indicating that N is re-absorbed before leaf abscission. Leaf dynamics and associated nutrient cycling differ significantly between secondary forests and mature forest. Ecosystem-level leaf structural and chemical traits are good predictors of the stage of the forest and explain well the differences in decomposition rates between secondary and primary forests.
A raw clay from Uruguay was modified with aluminium to obtain an aluminium pillared clay (Al-PILC). The solids were characterized by scanning electron microscopy, X-ray diffraction and nitrogen adsorption-desorption isotherms. The Al-PILC retained the typical laminar structure of montmorillonite. The specific surface area and the microporous volume of the Al-PILC, 235 m2 g-1 and 0.096 cm3 g-1, respectively, were much higher than those of the clay. The phosphate adsorption capacity of the Al-PILC was higher than those of the clay. The phosphate adsorption kinetic followed the pseudo-first-order model for both, the clay and the Al-PILC, and the phosphate adsorption isotherm for the Al-PILC fit the Freundlich model.
Let (R, 𝔪) be a Noetherian local ring and I an arbitrary ideal of R with analytic spread s. In  the authors proved the existence of a chain of ideals I ⊆ I[s] ⊆ ⋅⋅⋅ ⊆ I such that deg(PI[k]/I) < s − k. In this article we obtain a structure theorem for this ideals which is similar to that of K. Shah in  for 𝔪-primary ideals.
OBJECTIVES/SPECIFIC AIMS: High on-treatment platelet reactivity (HTPR) with clopidogrel imparts an increased risk for ischemic events in adults with coronary artery disease. Although more potent antiplatelet agents are available, clopidogrel remains the most commonly used P2Y12 inhibitor in Puerto Rico. Platelet reactivity varies with ethnicity and is influenced by both clinical and genetic variables; however, no clopidogrel pharmacogenetic studies with Puerto Rican patients have been reported. Therefore, we sought to identify clinical and genetic determinants of on-treatment platelet reactivity in a cohort of Puerto Rican patients with cardiovascular disease. METHODS/STUDY POPULATION: We performed a retrospective study of 111 Puerto Rican patients on 75 mg/day maintenance dose of clopidogrel. Patients were allocated into 2 groups: Group I, without HTPR; and Group II, with HTPR. Clinical data was obtained from the medical record. Platelet function was measured ex vivo using the VerifyNow® P2Y12 assay and HTPR was defined as P2Y12 reaction units (PRU)≥230. Genotyping of CYP2C19, ABCB1, PON1, PY2R12, B4GALT2, CES1, and PEAR1 was performed using Taqman® Genotyping Assays. RESULTS/ANTICIPATED RESULTS: The mean PRU across the cohort was 203±61 PRU (range, 8–324), and 42 (38%) patients had HTPR. One in four individuals carried at least 1 copy of the CYP2C19*2 variant allele. Hematocrit and PON1 p.Q192R variant were inversely correlated with platelet reactivity (p<0.05). Multiple logistic regression showed that 27% of the total variation in PRU was explained by a history of diabetes mellitus, hematocrit, CYP2C19*2, and PON1 p.Q192R. Body mass index (OR=1.15; CI: 1.03–1.27), diabetes mellitus (OR=3.46; CI: 1.05–11.43), hematocrit (OR=0.75; CI: 0.65–0.87), and CYP2C19*2 (OR=4.44; CI: 1.21–16.20) were the only independent predictors of HTPR. DISCUSSION/SIGNIFICANCE OF IMPACT: In a representative sample of Puerto Rican patients with cardiovascular disease, diabetes mellitus, hematocrit, CYP2C19*2, and PON1 p.Q192R were associated with on-treatment platelet reactivity. These factors may identify a subset of patients at higher risk for adverse events on clopidogrel in the Hispanic population.
Two metal fillers with TiC nanoparticles (TiC NPs) of less than 100 nm for the overlay process is an alternative to hardfacing for treating surfaces subjected to severe wear. In this work, the effect of tribological behavior for TiC NPs addition on two Co-based filler materials, as well as the dilutions, was studied. Mixtures of Co-based filler metals without and with 0.5% and 2% TiC NPs were deposited onto D2 steel plates using PTA (Plasma Transferred Arc). The BET surface area was 0.17 m2 g-1 and 0.31 m2 g-1, respectively, for Stellite 6 and 12. The distribution of ca 23% macroporous for Stellite 6 was sufficient to get inside the TiC NPs, as well as in the case of Stellite 12, with a pore distribution of ca 13%. Stellite 12 has an increase in the dilutions (70%) and enthalpies showed endothermic reactions. Stellite 6 with NPs was determined to be most effective in increasing the wear resistance.
A drift-kinetic model to describe the plasma dynamics in the scrape-off layer region of tokamak devices at arbitrary collisionality is derived. Our formulation is based on a gyroaveraged Lagrangian description of the charged particle motion, and the corresponding drift-kinetic Boltzmann equation that includes a full Coulomb collision operator. Using a Hermite–Laguerre velocity space decomposition of the gyroaveraged distribution function, a set of equations to evolve the coefficients of the expansion is presented. By evaluating explicitly the moments of the Coulomb collision operator, distribution functions arbitrarily far from equilibrium can be studied at arbitrary collisionalities. A fluid closure in the high-collisionality limit is presented, and the corresponding fluid equations are compared with previously derived fluid models.