Кінетика сумісного виділення цинку і нікелю з розбавлених електролітів

Досліджені закономірності виділення цінку, нікелю і цинк-нікелевого сплаву з розведених електролітів, що містять в якості лігандів амінокислоту та аміак. Найкращі технологічні параметри та якість покрить отримані при спільному вмісті у розчині обох лігандів. Запропонований електроліт характеризується високою стабільністю, є технологічним та екологічно безпечним.The mechanisms of zinc, nickel and zinc-nickel alloy deposition from diluted electrolytes, containing amino acid or ammonia as a ligand, were investigated. The very technological characteristics and coatings quality were obtained if the electrolyte contained both of the ligands. The suggested electrolyte is characterized by high stability, processibility and it is ecologically safe

Comparisons of Supergranule Characteristics During the Solar Minima of Cycles 22/23 and 23/24

Supergranulation is a component of solar convection that manifests itself on the photosphere as a cellular network of around 35 Mm across, with a turnover lifetime of 1-2 days. It is strongly linked to the structure of the magnetic field. The horizontal, divergent flows within supergranule cells carry local field lines to the cell boundaries, while the rotational properties of supergranule upflows may contribute to the restoration of the poloidal field as part of the dynamo mechanism that controls the solar cycle. The solar minimum at the transition from cycle 23 to 24 was notable for its low level of activity and its extended length. It is of interest to study whether the convective phenomena that influences the solar magnetic field during this time differed in character to periods of previous minima. This study investigates three characteristics (velocity components, sizes and lifetimes) of solar supergranulation. Comparisons of these characteristics are made between the minima of cycles 22/23 and 23/24 using MDI Doppler data from 1996 and 2008, respectively. It is found that whereas the lifetimes are equal during both epochs (around 18 h), the sizes are larger in 1996 (35.9 +/- 0.3 Mm) than in 2008 (35.0 +/- 0.3 Mm), while the dominant horizontal velocity flows are weaker (139 +/- 1 m/s in 1996; 141 +/- 1 m/s in 2008). Although numerical differences are seen, they are not conclusive proof of the most recent minimum being inherently unusual.Comment: 22 pages, 5 figures. Solar Physics, in pres

Ultrametric Logarithm Laws, II

We prove positive characteristic versions of the logarithm laws of Sullivan and Kleinbock-Margulis and obtain related results in Metric Diophantine Approximation.Comment: submitted to Montasefte Fur Mathemati

On the Behavior of the Effective QCD Coupling alpha_tau(s) at Low Scales

The hadronic decays of the tau lepton can be used to determine the effective charge alpha_tau(m^2_tau') for a hypothetical tau-lepton with mass in the range 0 < m_tau' < m_tau. This definition provides a fundamental definition of the QCD coupling at low mass scales. We study the behavior of alpha_tau at low mass scales directly from first principles and without any renormalization-scheme dependence by looking at the experimental data from the OPAL Collaboration. The results are consistent with the freezing of the physical coupling at mass scales s = m^2_tau' of order 1 GeV^2 with a magnitude alpha_tau ~ 0.9 +/- 0.1.Comment: 15 pages, 4 figures, submitted to Physical Review D, added references, some text added, no results nor figures change

The Life and Death of Barn Beetles: Faunas from Manure and Stored Hay inside Farm Buildings in Northern Iceland

This research was funded by the Commonwealth Scholarship Commission and received support from the Research Budget of the Department of Archaeology at the University of Aberdeen. This project was undertaken as part of doctoral studies supervised by Dr Karen Milek, to whom V.F. is especially grateful for her support and advice. Thomas Birch, Sigrún Inga Garðarsdóttir, and Paul Ledger provided invaluable assistance during fieldwork. V.F. would like to dedicate this paper to Tom and Sía, who met during this fieldwork and are getting married this year. Many people from Fornleifastofnun Íslands – Garðar Guðmundsson, Ólöf Þorsteinsdóttir, Þóra Pétursdóttir, Adolf Friðriksson and Uggi Ævarsson – as well as Unnstein Ingason, Ágústa Edwald, and Mark Young, helped with fieldwork logistics. Special thanks are due to all the Icelandic farmers and their families who kindly allowed us to collect insects on their farms and provided help when needed: Hermann Aðalsteinsson, Hermína Fjóla Ingólfsdóttir, Guðmundur Skúlason, Sigrún Á. Franzdóttir, Dúna Magnúsdóttir, Sverrir Steinbergsson, Valgeir Þorvaldsson, Reynir Sveinsson, Jónas Þór Ingólfsson, and Ívar Ólafsson. Eva Panagiotakopulu, Jan Klimaszewski, Ales Smetana, Georges Pelletier, Gabor Pozsgai, and Jenni Stockham helped with some of the beetle identifications. A.J.D. acknowledges the support of National Science Foundation through ARC 1202692. Consultation of the BugsCEP database (Buckland & Buckland, 2006) aided the redaction of this paper. The authors would like to thank David Smith and two anonymous reviewers for insightful comments that helped improve the quality of this paper.Peer reviewedPostprin

The Relationship Between Discrimination and Missed HIV Care Appointments Among Women Living with HIV

Receiving regular HIV care is crucial for maintaining good health among persons with HIV. However, racial and gender disparities in HIV care receipt exist. Discrimination and its impact may vary by race/ethnicity and gender, contributing to disparities. Data from 1578 women in the Women’s Interagency HIV Study ascertained from 10/1/2012 to 9/30/2016 were used to: (1) estimate the relationship between discrimination and missing any scheduled HIV care appointments and (2) assess whether this relationship is effect measure modified by race/ethnicity. Self-reported measures captured discrimination and the primary outcome of missing any HIV care appointments in the last 6 months. Log-binomial models accounting for measured sources of confounding and selection bias were fit. For the primary outcome analyses, women experiencing discrimination typically had a higher prevalence of missing an HIV care appointment. Moreover, there was no statistically significant evidence for effect measure modification by race/ethnicity. Interventions to minimize discrimination or its impact may improve HIV care engagement among women

Seismology of the Sun : Inference of Thermal, Dynamic and Magnetic Field Structures of the Interior

Recent overwhelming evidences show that the sun strongly influences the Earth's climate and environment. Moreover existence of life on this Earth mainly depends upon the sun's energy. Hence, understanding of physics of the sun, especially the thermal, dynamic and magnetic field structures of its interior, is very important. Recently, from the ground and space based observations, it is discovered that sun oscillates near 5 min periodicity in millions of modes. This discovery heralded a new era in solar physics and a separate branch called helioseismology or seismology of the sun has started. Before the advent of helioseismology, sun's thermal structure of the interior was understood from the evolutionary solution of stellar structure equations that mimicked the present age, mass and radius of the sun. Whereas solution of MHD equations yielded internal dynamics and magnetic field structure of the sun's interior. In this presentation, I review the thermal, dynamic and magnetic field structures of the sun's interior as inferred by the helioseismology.Comment: To be published in the proceedings of the meeting "3rd International Conference on Current Developments in Atomic, Molecular, Optical and Nano Physics with Applications", December 14-16, 2011, New Delhi, Indi

Influence of Low-Degree High-Order p-Mode Splittings on the Solar Rotation Profile

The solar rotation profile is well constrained down to about 0.25 R thanks to the study of acoustic modes. Since the radius of the inner turning point of a resonant acoustic mode is inversely proportional to the ratio of its frequency to its degree, only the low-degree p modes reach the core. The higher the order of these modes, the deeper they penetrate into the Sun and thus they carry more diagnostic information on the inner regions. Unfortunately, the estimates of frequency splittings at high frequency from Sun-as-a-star measurements have higher observational errors due to mode blending, resulting in weaker constraints on the rotation profile in the inner core. Therefore inversions for the solar internal rotation use only modes below 2.4 mHz for l < 4. In the work presented here, we used an 11.5 year-long time series to compute the rotational frequency splittings for modes l < 4 using velocities measured with the GOLF instrument. We carried out a theoretical study of the influence of the low-degree modes in the region 2 to 3.5 mHz on the inferred rotation profile as a function of their error bars.Comment: Accepted for publication in Solar Physics. 17 Pages, 9 figure

Perspectives in Global Helioseismology, and the Road Ahead

We review the impact of global helioseismology on key questions concerning the internal structure and dynamics of the Sun, and consider the exciting challenges the field faces as it enters a fourth decade of science exploitation. We do so with an eye on the past, looking at the perspectives global helioseismology offered in its earlier phases, in particular the mid-to-late 1970s and the 1980s. We look at how modern, higher-quality, longer datasets coupled with new developments in analysis, have altered, refined, and changed some of those perspectives, and opened others that were not previously available for study. We finish by discussing outstanding challenges and questions for the field.Comment: Invited review; to appear in Solar Physics (24 pages, 6 figures

Wnt signalling and cancer stem cells

[Abstract] Intracellular signalling mediated by secreted Wnt proteins is essential for the establishment of cell fates and proper tissue patterning during embryo development and for the regulation of tissue homeostasis and stem cell function in adult tissues. Aberrant activation of Wnt signalling pathways has been directly linked to the genesis of different tumours. Here, the components and molecular mechanisms implicated in the transduction of Wnt signal, along with important results supporting a central role for this signalling pathway in stem cell function regulation and carcinogenesis will be briefly reviewed.Ministerio de Ciencia e Innovación; SAF2008-0060