The syringe sampler: An inexpensive alternative borehole sampling technique for CO2-rich fluids during mineral carbon storage

Mineral carbon storage involves the dissolution of injected gaseous or supercritical CO2 followed by interaction of the carbonated solution with the host rock at depth resulting in the precipitation of carbonate minerals. Monitoring of elemental chemistry and tracers is required to evaluate the evolution of the fluid geochemistry and the degree of CO2 mineralization during its injection into the subsurface. To avoid degassing during sampling, which is a common feature of commercial groundwater samplers, especially vacuum samplers, a syringe-like sampler was designed, constructed, and tested in the lab and field. This system was successfully deployed during the injection of 175 tons of pure gaseous CO2 at the CarbFix injection site in Hellisheidi, SW Iceland. This study presents in detail this sampling tool and its application to the monitoring of the CO2-rich fluid evolution during subsurface carbonation. The syringe sampler was developed as a flexible and mobile unit of low investment and operating costs making it an attractive option for deployment at small scale carbon storage demonstration sites that do not command the budgets to deploy commercial alternatives, e.g. from the oil and gas industry

Scaling of mixed structure functions in turbulent boundary layers

We address the issue of the scaling of the anisotropic components of the hierarchy of correlation tensors in the logarithmic region of a turbulent boundary layer over a flat plate, at Re?15000. We isolate the anisotropic observables by means of decomposition tools based on the SO(3) symmetry group of rotations. By employing a dataset made of velocity signals detected by two X probes, we demonstrate that the behavior of the anisotropic fluctuations throughout the boundary layer may be understood in terms of the superposition of two distinct regimes. The transition is controlled by the magnitude of the mean shear and occurs in correspondence with the shear scale. Below the shear scale, an isotropy-recovering behavior occurs, which is characterized by a set of universal exponents which roughly match dimensional predictions based on Lumley's argument [J. L. Lumley, Phys. Fluids 8, 1056 (1965)]. Above the shear scale, the competition between energy production and transfer mechanisms gives rise to a completely different scenario with strong alterations of the observed scaling laws. This aspect has significant implications for the correct parametrization of the anisotropy behavior in the near wall region since, approaching the wall, an increasingly larger fraction of the scaling interval tends to conform to the shear-dominated power laws

Probability density function of turbulent velocity fluctuations in rough-wall boundary layer

The probability density function of single-point velocity fluctuations in turbulence is studied systematically using Fourier coefficients in the energy-containing range. In ideal turbulence where energy-containing motions are random and independent, the Fourier coefficients tend to Gaussian and independent of each other. Velocity fluctuations accordingly tend to Gaussian. However, if energy-containing motions are intermittent or contaminated with bounded-amplitude motions such as wavy wakes, the Fourier coefficients tend to non-Gaussian and dependent of each other. Velocity fluctuations accordingly tend to non-Gaussian. These situations are found in our experiment of a rough-wall boundary layer.Comment: 6 pages, to appear in Physical Review

Common Genetic Variation and Age of Onset of Anorexia Nervosa

Background: Genetics and biology may influence the age of onset of anorexia nervosa (AN). The aims of this study were to determine whether common genetic variation contributes to age of onset of AN and to investigate the genetic associations between age of onset of AN and age at menarche. Methods: A secondary analysis of the Psychiatric Genomics Consortium genome-wide association study (GWAS) of AN was performed, which included 9335 cases and 31,981 screened controls, all from European ancestries. We conducted GWASs of age of onset, early-onset AN (&lt;13 years), and typical-onset AN, and genetic correlation, genetic risk score, and Mendelian randomization analyses. Results: Two loci were genome-wide significant in the typical-onset AN GWAS. Heritability estimates (single nucleotide polymorphism–h2) were 0.01–0.04 for age of onset, 0.16–0.25 for early-onset AN, and 0.17–0.25 for typical-onset AN. Early- and typical-onset AN showed distinct genetic correlation patterns with putative risk factors for AN. Specifically, early-onset AN was significantly genetically correlated with younger age at menarche, and typical-onset AN was significantly negatively genetically correlated with anthropometric traits. Genetic risk scores for age of onset and early-onset AN estimated from independent GWASs significantly predicted age of onset. Mendelian randomization analysis suggested a causal link between younger age at menarche and early-onset AN. Conclusions: Our results provide evidence consistent with a common variant genetic basis for age of onset and implicate biological pathways regulating menarche and reproduction.</p

TEACHERS' OPINIONS RELATED TO THE EXTENT OF CRITICAL MANAGEMENT SKILLS FOR PRINCIPALS

Günümüz değişen okul yönetimi bağlamında, müdürlerin yönetimi becerileri önem kazanmaktadır. Bu çalışma çeşitli yönetim becerilerinin okul müdürleri için önem derecelerini öğretmen görüşleriyle belirleyebilmeyi amaçlamıştır. Çalışma kapsamında öğretmen görüşlerinin kişisel özelliklere göre farklılarına bakılmıştır. Sonuçlar öğretmenlerin, okul müdürlerinin yönetim becerilerini "yüksek" düzeyde önemli gördüklerini ortaya koymuştur. Ayrıca bireysel farkındalık becerileri alt boyutunda kadın ve erkek öğretmenlerin görüşleri arasında farklılık olduğu ve bu farklılığın kadın öğretmenlerin lehine olduğu gözlenmiştir. Aynı alt boyutta, okul müdürü olmak isteyen öğretmenler ile okul müdürü olmak istemeyen öğretmenlerin görüşleri arasında müdür olmak isteyenler lehine farklılık olduğu görülmüştür. Kıdem değişkenine göre de katılımcı görüşleri arasında farklılıklar bulunmuştur. En önemli yönetim becerileri olarak ise birinci sırada"Personelin nasıl değerlendirileceği"; ikinci sırada "Eğitim sistemi içinde bulunan herkesin (aile, çevre vb.) eğitim-öğretim sürecine katılımını cesaretlendirmek"; üçüncü sırada ise "Öğrenciler üzerinde katkı sağlayıcı farklılıklar yaratabilme arzusunu göstermek" olarak sıralanmıştır. The changing context of school management in our age makes principals' management skills important. This study aimed to reveal teachers' opinions related to the extent of critical management skills for principals. It also aimed to explore if there were any differences in teachers' opinions with regard to their demographic variables. Results showed that teachers think that the extents of management skills for principals were critical on a high degree. In addition the results showed that female teachers were more concerned about those critical skills in self-awareness dimension. In the same dimension, there was a statistically significant difference between teachers who planned to be a principal and teachers who did not. According to teachers' opinions, the item "how to assess staff" was the most important skill for principals, the second was "ability to encourage involvement by all parties in the educational system", and the third was "demonstrating a desire to make a significant difference in the lives of students.