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Historically, the existence of dark matter has been postulated to resolve discrepancies between astrophysical observations and accepted theories of gravity. In particular, the measured rotation curve of galaxies provided much experimental support to the dark matter concept. However, most theories used to explain the rotation curve have been restricted to the Newtonian potential framework, disregarding the general relativistic corrections associated with mass currents. In this paper it is shown that the gravitomagnetic field produced by the currents modifies the galactic rotation curve, notably at large distances. The coupling between the Newtonian potential and the gravitomagnetic flux function results in a nonlinear differential equation that relates the rotation velocity to the mass density. The solution of this equation reproduces the galactic rotation curve without recourse to obscure dark matter components, as exemplified by three characteristic cases. A bi-dimensional model is developed that allows to estimate the total mass, the central mass density, and the overall shape of the galaxies, while fitting the measured luminosity and rotation curves. The effects attributed to dark matter can be simply explained by the gravitomagnetic field produced by the mass currents.

This work presents a novel approach to well established concepts of gravity, formulating a new and consistent gravitoelectromagnetic theory. The long standing gravitoelectromagnetic field theory is considered in the framework of Hamilton’s principle. A variational formulation based on this principle describes the dynamics of a fully-relativistic perfect fluid in the presence of the gravitoelectromagnetic field in flat space, leading to the definition of the fluid and field energy-momentum tensors. A relativistic Cauchy invariant for a compressible fluid immersed in the gravitoelectromagnetic field is demonstrated. The gravitoelectromagnetic fluid equations of motion are written in covariant form suited for calculating higher-order relativistic effects. The integral form of the conservation theorems is presented, as well as equations that describe the excitation of gravitoelectromagnetic waves. As an application, the equations of motion are used to derive the equation that governs the galactic rotation according to gravitoelectromagnetism.

This article makes the connection between the new gravitoelectromagnetic theory presented in the part I paper and general gravity in its weak formulation. The perturbation in the metric tensor is obtained in terms of the flat-space total energy–momentum tensor given by the sum of the consistent fully relativistic fluid and gravitoelectromagnetic field contributions. Expressions for the perturbed metric in the internal (fluid) and external (vacuum) regions are given in terms of the fluid and field variables. This formulation of gravitoelectromagnetism is compatible with the formation of gravitational waves. The geodesic equation is obtained in both the internal and external regions, including new terms neglected in the standard gravitomagnetic formulation. It is shown that the new terms reproduce the anomalous shift of planetary precession, which results from a balance between the gravitoelectric and gravitomagnetic forces.

This chapter describes the collaborative writing experiences of a multidisciplinary group of educators brought together through an International Collaborative Writing Group (ICWG) initiative originally organized by the International Society for the Scholarship of Teaching and Learning (ISSoTL) in 2012. Our ICWG writing partnership helped us develop our scholarship in ways that might not have otherwise been accomplished, had we worked alone or even with colleagues in our same institution or country. Through an analysis of a collection of individual reflective narratives about our collaborative writing experiences, we describe opportunities, affordances, inhibitors, and enablers for this approach to collaborative writing. We delineate the community of practice that we have successfully developed and how it has helped each of us develop our Scholarship of Teaching and Learning (SoTL). We share the mechanisms that we have used to facilitate our work; the types of choices we have made about what research areas to explore that fit with our interests and the constraints of distance-based collaboration; and, most importantly, the ways in which our writing partnership has developed a stronger understanding of what SoTL is, and can be, moving forward.

Hamilton's principle is applied to obtain the equations of motion for fully relativistic collision-free plasma. The variational treatment is presented in both the Eulerian and Lagrangian frameworks. A Clebsch representation of the plasma fluid equations shows the connection between the Lagrangian and Eulerian formulations, clarifying the meaning of the multiplier in Lin's constraint. The existence of a fully relativistic hydromagnetic Cauchy invariant is demonstrated. The Lagrangian approach allows a straightforward determination of the Hamiltonian density and energy integral. The definitions of momentum, stress, and energy densities allow one to write the conservation equations in a compact and covariant form. The conservation equations are also written in an integral form with an emphasis on a generalized virial theorem. The treatment of boundary conditions produces a general expression for energy density distribution in plasma fluid.

Background: Therapeutic advancements following the introduction of autologous stem cell transplantation and 'novel' agents have significantly improved clinical outcomes for patients with multiple myeloma (MM). Increased life expectancy, however, has led to renewed concerns about the long-term risk of second primary malignancies (SPMs). This review outlines the most up-to-date knowledge of possible host-, disease-, and treatment-related risk factors for the development of SPMs in patients with MM, and provides practical recommendations to assist physicians. Design: A Panel of International Myeloma Working Group members reviewed the most relevant data published in the literature as full papers, or presented at meetings of the American Society of Clinical Oncology, American Society of Hematology, European Hematology Association, or International Myeloma Workshops, up to June 2016. Here, we present the recommendations of the Panel, based on this literature review. Results: Overall, the risk of SPMs in MM is low, multifactorial, and partially related to the length of patients' survival and MM intrinsic susceptibility. Studies suggest a significantly increased incidence of SPMs when lenalidomide is administered either following, or concurrently with, oral melphalan. Increased SPM incidence has also been reported with lenalidomide maintenance following high-dose melphalan, albeit to a lesser degree. In both cases, the risk of death from MM was significantly higher than the risk of death from SPMs, with lenalidomide possibly providing a survival benefit. No increase in SPM incidence was reported with lenalidomide plus dexamethasone (without melphalan), or with bortezomib plus oral melphalan, dexamethasone, or thalidomide.Conclusion: In general, the risk of SPMs should not alter the current therapeutic decision-making process in MM. However, regimens such as lenalidomide plus dexamethasone should be preferred to prolonged exposure to lenalidomide plus oral melphalan. SPM risk should be carefully discussed with the patient in the context of benefits and risks of different treatment options. © The Author 2016.

We examine the effect of nutrient prices and other socio-economic and health factors on the Body Mass Index (BMI) of Canadians using the Canadian Community Health Survey (CCHS). The CCHS data does not include information on nutrition intake, and so the price of fat, carbohydrates and protein are included to capture the effects of diet on BMI. The results indicate that changes in nutrient prices in the model have statistically significant impacts on BMI and the direction of the impacts corresponds to hypotheses from the nutrition literature. However, all estimates are inelastic so that the effect of fat taxes or thin subsidies is small. The results also indicate that education is negatively related and income is positively related to BMI.

In the global higher education sector, government accountability initiatives are increasingly focused on degree-level competencies that may be expected from university graduates. The purpose of this paper was to examine the extent to which SoTL reflects this increased interest in student learning across the degree program. Articles (N=136) published in three international SoTL journals, over the past three years, were systematically reviewed using a framework that concentrated on the extent to which they reflected a focus of (a) teaching-emphasis versus learning-emphasis and (b) unit-level (subject, course) versus degree-/program-level. Our analysis indicated that the majority of SoTL publications (47%) were focused at the level of a single unit with an emphasis on teaching practice; in contrast, only a small minority of SoTL publications (9%) were focused at the level of the overall degree with an emphasis on learning processes. Drawing on our review, we highlight SoTL publications that exemplify the inquiry into student learning at the level of the degree program and offer questions to guide future SoTL inquiries.

Lesions/irritations of the obturator internus muscle (OIM) are rare, several differential diagnoses are possible.This paper describes the case of an OIM injury in a professional football player.On clinical examination, painful internal rotation of the hip joint was an indication for a lesion/irritation of the OIM. MRI was the procedure of choice for imaging. Movement analysis served to detect a functional malposition.A short recovery time requires functional treatment as well as the use of orthopaedic aids to correct possible deformities.

In a prior work, a novel cooling approach for the blown film application was developed, called Multi-Jet. In contrast to a conventional cooling ring, this alternative cooling system guides the air vertically on the film surface, using several slit nozzles over the whole tube formation zone. In addition, the bubble expansion zone is surrounded by a housing. In this context, the cooling jets penetrate the boundary sublayer on the film surface that is developed by the fast flowing cooling air. The advantage of the housing can been seen in the disablement of the interaction of the cooling jet and the static ambient air. Besides the exhausting of the monomer loaded air, the housing allows to realize a heat recovery of the warmed cooling air. In this paper, an experimental and numerical investigation of the novel cooling system is shown. Here a comparison is done for several different process conditions with and without the use of the housing for the tube formation zone. By the means of a CFD-simulation, the co...

This paper examines three alternative types of fat taxes to determine how effective they may be in reducing obesity. Upon the examination of the available evidence as to the effectiveness of fat taxes in reducing obesity authors conclude that all types of fat taxes are not sufficiently specific in targeting obesity. In some cases imposition of fat tax may actually lead to reversal of the intended effect. Therefore, the use of taxes to reduce obesity and promote healthy outcomes is not recommended.

A table of Bonferroni Chi-square limits is given for R simultaneous tests, where R = 1(1) 30(5) 150 at the level of α = 0.05 for 1 to 100 degrees of freedom. At the level α = 0.01 the limits are given for R = 1(1) 30, correspondingly. Additionally, a table of Bonferroni Chi-square limits for 1 degree of freedom is given at both levels up to R(5%) = 300 and R(1 %) = 60 allowing for one-sided as well as two-sided testing. Reading of both tables is illustrated by biomedical examples. Methodological problems and clinical applications are discussed with special reference to configural frequency analysis (CFA).

The simulation of eddy currents induced in the vacuum vessel and central column of spherical tokamaks is discussed, improving upon previously published methods. The present model allows us to describe the vacuum vessel either as a thin shell or as a large collection of rings, formally reducing the problem to a set of coupled circuit equations. Results are compared with measurements of the electromotive force and current distribution on the vacuum vessel of the ETE spherical tokamak. The mathematical model is described in detail, enabling application to other machines.

Over the last years, several studies on harmful events (h. e.) in soccer have been published. The aim was to develop a ranking of these studies according to their evidence, and to analyse the data with respect to the number of study participants, athletes' status, gender distribution, and genesis of harmful events in soccer.Between 1976 and 2011, the data bases MEDLINE, EBMR, and SPOTLIT were scanned by the keywords/combinations: soccer, acute injuries, overuse injuries, training, and match. In doing so, 644 initially potential relevant articles were found. On the basis of the QUORUM standard, 78 potentially relevant articles were filtered out, and an EVIDENCE BASED LEVEL (EBL) was assigned. The results were rated according to importance and shown descriptively, because the heterogeneity of the study inhibited meta-analytical evaluation.23 % of the publications could be assigned to EBL 2a - 2c, 27 % to EBL 3a and 3b, and 50 % to EBL 4 and 5. The studies comprised altogether 22 294 male and 2375 female athletes; 87 % of the male and 29 % of the female were professional athletes. 7 usable publications with a total of 8011 h. e. in men and 6 publications with 1055 h. e. in women dealt with contact/non-contact genesis of h. e.. 46 % male (72 % female) athletes suffered from h. e. caused by contact events, and 54 % male (28 % female) athletes suffered from h. e. caused by non-contact events. The distribution of acute and overuse injuries was analysed in 9969 h. e. in men (11 publications), and in 624 h. e. in women (5 publications). On average, the number of acute injuries (90 % male, 86 % female) was much higher than that of overuse injuries. The prevalence of h. e. with respect to training or match playing was analysed in 11 studies with 10 078 h. e. in men, and in 4 studies with 546 harmful events in women. 35 % of men's h. e. occurred during training and 65 % during matches, whereas 60 % of the women's h. e. occurred during training and 40 % during matches.The number of athletes included in the studies is quite low in relation to the number of active athletes. Studies of professional athletes are over-represented. Independent of gender, there are more acute injuries than overuse injuries, whereas the distribution of harmful events with respect to genesis and occurrence during training and match is gender-specific. The studies' evidence level is quite low in relation to the socio-economic significance of this kind of sport; the studies' evidence is higher for women.

Small tokamaks have an important role in fusion research. More than 40 small tokamaks are operational. Research on small tokamaks has created a scientific basis for the scaling-up to larger tokamaks. Well-known scientific and engineering schools, which are now determining the main directions of fusion science and technology, have been established through research on small tokamaks. Combined efforts within a network of small and medium size tokamaks will further enhance the contribution of small tokamaks. A new concept of interactive coordinated research using small tokamaks in the mainstream fusion science areas, in testing of new diagnostics, materials and technologies as well as in education, training and broadening of the geography of fusion research in the scope of the IAEA Coordinated Research Project, is presented.

This paper describes an analytical model of the eddy currents that circulate in the central column of the spherical tokamak ETE (Experimento Tokamak Esferico). The varying magnetic flux that forms and maintains the plasma current also induces currents in the copper bars of the toroidal field magnet central column, around which the ohmic heating solenoid was tightly wound. During the plasma startup phase the eddy currents strongly affect the performance of the ohmic heating system, and must be taken into account in the development of circuit models for the power system of ETE. Theoretical calculations of the ohmic solenoid impedance, including the eddy current and proximity effects, are compared with experimental values.

A Green's function method is developed to evaluate the currents induced during startup in the vacuum vessel of ETE (Experimento Tokamak Esferico). The non-homogeneous integral equation for the axisymmetric eddy currents distribution is determined using a thin shell approximation for the vacuum vessel and local curvilinear coordinates. This problem is reduced to a circuit model by adopting spectral representations both for the centreline of the vacuum vessel and the surface current density. Results of this model are compared with the distribution of eddy currents measured in ETE.

Longitudinal dielectric permittivity elements are derived for radio-frequency waves in an axisymmetric tokamak with elliptic magnetic surfaces, for arbitrary elongation and inverse aspect ratio. A collisionless plasma model is considered. Drift-kinetic equation is solved separately for untrapped (passing or circulating) and three groups of the trapped particles as a boundary-value problem. Bounce resonances are taken into account. A coordinate system with the “straight” magnetic field lines is used. Permittivity elements, evaluated in the paper, are suitable to estimate the wave dissipation by electron Landau damping (e.g., during the plasma heating and current drive generation) in the frequency range of Alfven, fast magnetosonic, and lower hybrid waves, for both the large and low aspect ratio tokamaks. The dissipated wave power is expressed by the summation of terms including the imaginary parts of both the diagonal and nondiagonal elements of the longitudinal permittivity.Longitudinal dielectric permittivity elements are derived for radio-frequency waves in an axisymmetric tokamak with elliptic magnetic surfaces, for arbitrary elongation and inverse aspect ratio. A collisionless plasma model is considered. Drift-kinetic equation is solved separately for untrapped (passing or circulating) and three groups of the trapped particles as a boundary-value problem. Bounce resonances are taken into account. A coordinate system with the “straight” magnetic field lines is used. Permittivity elements, evaluated in the paper, are suitable to estimate the wave dissipation by electron Landau damping (e.g., during the plasma heating and current drive generation) in the frequency range of Alfven, fast magnetosonic, and lower hybrid waves, for both the large and low aspect ratio tokamaks. The dissipated wave power is expressed by the summation of terms including the imaginary parts of both the diagonal and nondiagonal elements of the longitudinal permittivity.

The fundamental mechanisms of the deformation of heavily deformed multiphase materials are not clearly understood despite the vast literature and the amount of data on this subject. This paper presents a new plastic flow mechanism observed by in-situ transmission electron microscopy deformation on Cu-Nb continuous multifilamentary nanostructured composites. The observed mechanism is interpreted in terms of dislocation loops nucleating in closely spaced parallel planes in the Cu channels. This behaviour explains many previous observations made on such composites such as the semicoherency of the interface and the 4° disorientation between the two phases. The modelling of the loop mechanism predicts the strength of the Cu-Nb nanocomposites. The very good agreement between the model and the experimental data suggests that the assumptions based on the in-situ observations are valid. The basic aspects of co-deformation of fcc-bcc nanostructured systems are reviewed in this new context.

The Scholarship of Teaching and Learning (SoTL) has been described as the fastest growing academic development movement in higher education. As this field of inquiry matures, there is a need to understand how SoTL research is conducted. The purpose of our study was toinform this debate by investigating research approaches used in SoTL publications. We analysed 223 empirical research studies published from 2012 to 2014 in three explicitly focused SoTL journals. We classified the studies as either qualitative, quantitative, or mixed methods using an analytical framework devised from existing literature on research methods. We found that the use of the three research designs was fairly evenly distributed across the papers examined: qualitative (37.2%), quantitative (29.6%), and mixed methods (33.2%). However, there was an over-reliance on data collection from a single source in 83.9% of papers analysed, and this source was primarily students. There was some, but limited, evidence of the use of triangulation through the use of multiple data collection instruments (e.g. survey, assessment tasks, grade databases). Similarly, only one-third of publications classified as mixed methods integrated the analysis and interpretation of the qualitative and quantitative data equally within the study. We conclude that current SoTL research is characterised by methodological pluralism but could be advanced through inclusion of more diverse approaches, such as close reading, and adoption of strategies known to enhance the quality of research, for example, triangulation and visual representation.

This article presents an analytical method to evaluate the equilibrium of plasmas in axisymmetric, nested magnetic configurations relevant for tokamak experiments. The emphasis is in the use of spectral representations of the magnetic flux surfaces and variational methods to solve the Grad-Shafranov equation. Approximate solutions are obtained based on power series expansions of the variational moment equations and sectionally continuous representations of the Fourier amplitudes. The method is applied to an up-down asymmetric configuration of an ITER-like tokamak in a fixed-boundary equilibrium. The free-boundary case is treated in the Paper II [G. O. Ludwig, Phys. Plasma 24, 092503 (2017)].

Deformation mechanism in high strength Cu/Nb nanocomposites have been investigated through in situ TEM observations in tension. The results explain the particular interface microstructure that was previously observed by high resolution TEM. Moreover, the observed loops mechanism could be modeled, and the simulation of the very high mechanical properties of this type of composites is in good agreement with experimental data. Some criteria for higher strength composites are proposed.

A self-consistent equilibrium calculation, valid for arbitrary aspect ratio tokamaks, is obtained through a direct variational technique that reduces the equilibrium solution, in general obtained from the 2D Grad-Shafranov equation, to a 1D problem in the radial flux coordinate ρ. The plasma current profile is supposed to have contributions of the diamagnetic, Pfirsch-Schluter and the neoclassical ohmic and bootstrap currents. An iterative procedure is introduced into our code until the flux surface averaged toroidal current density JT, converges to within a specified tolerance for a given pressure profile and prescribed boundary conditions. The convergence criterion is applied between the JT profile used to calculate the equilibrium through the variational procedure and the one that results from the equilibrium and given by the sum of all current components. The ohmic contribution is calculated from the neoclassical conductivity and from the self-consistently determined loop voltage in order to give the prescribed value of the total plasma current. The bootstrap current is estimated through the full matrix Hirshman-Sigmar model with the viscosity coefficients as proposed by Shaing, which are valid in all plasma collisionality regimes and arbitrary aspect ratios. The results of the self-consistent calculation are presented for the low aspect ratio tokamak Experimento Tokamak Esferico. A comparison among different models for the bootstrap current estimate is also performed and their possible limitations to the self-consistent calculation is analysed.

This paper presents a method for calculating the external inductance and mutual inductance coefficients of tokamak plasma configurations in a consistent way. The method actually solves the external equilibrium problem, linking the poloidal equilibrium fields with the value of the total plasma current and the geometric parameters that describe the plasma cross section. This link imposes constraints upon the values of the inductance for superconducting tori obtained by a previous method described by S. P. Hirshman and G. H. Neilson [Phys. Fluids 29, 790 (1986)]. Only if these constraints are properly taken into account do their results correspond to real tokamak equilibrium configurations. The present method is illustrated by calculating the external equilibrium parameters for a wide range of values of the tokamak aspect ratio. Of particular interest are the results for the external inductance, the elongation, and the vertical equilibrium field in the low aspect-ratio range A

A direct variational method based on an energy principle has been developed to calculate approximate solutions to the tokamak plasma equilibrium equation. The method uses a spectral representation of the magnetic flux surfaces in terms of Chebyshev polynomials. This representation allows analytic evaluation of the flux-surface average integrals, eliminating the poloidal angle dependence of the plasma internal energy. In this form the variational problem is reduced to the determination of the spectral coefficients as functions of the radial coordinate. Global approximate solutions are obtained by the introduction of trial functions for the coefficients parametrized by a set of constants determined in such a way as to render the energy stationary. The method is illustrated with applications to the START and MAST spherical tokamaks.

A first estimate of the bootstrap current in the ETE (Experimento Tokamak Esf?rico) small aspect ratio tokamak using the Hirshman single-ion collisionless model shows that we can expect a ratio of 15 to 30% of total bootstrap current in relation to the total equilibrium current depending on the optimization level of the plasma profile parameters. Bootstrap current levels basically depend on the values which must be kept under a critical level due to stability conditions and current alignment requirements. Preliminary studies of Shaing's predictions regarding bootstrap current calculations in collisional plasmas are briefly described and different methods for the trapped particle fraction calculation are also illustrated.

A direct variational method based on an energy principle is applied to obtain approximate magnetohydrodynamic equilibria for tokamak plasmas. The geometry of the nested magnetic flux surfaces is specified by a model that includes displacement, elongation and triangularity effects. The radial dependence in flux coordinates is described by a consistent set of trial functions which allows analytical calculation of the flux-surface averaged internal energy density of the plasma. Approximate solutions of the variational problem are obtained for arbitrary aspect-ratio tokamaks using a one-parameter optimization procedure.

Strukturen, Architektur und Genese der Stauchmoräne Peski/ Belorussland werden beschrieben und mit der Stauchmoräne Jasmund/Rügen verglichen. In beiden Stauchmoränen sind Oberkreide- und Pleistozänfolgen, bei Peski zusätzlich tertiäre Sande, glazigen gefaltet und verschuppt worden. Die Falten und Schuppen gleichen sich in beiden Stauchzonen in den Formen und Ausmaßen weitgehend. In ihrer Architektur unterscheiden sich beide Großstrukturen jedoch prinzipiell voneinander: Bei Peski ist eine bogenförmige Stauchzone an der Stirn eines ausgedehnten Eislobus entstanden; auf Jasmund ist der Eisstrom, der der Ostseesenke gefolgt war, durch ein höher liegendes Areal zweigeteilt worden und hat dieses samt den ersten Stauchwällen zunächst umflossen. Hier ist die Stauchung von den Flanken zweier Eiszungen ausgegangen. Der Interpretation als einer spitzwinkligen Kerbstauchung wird die Vorstellung einer in der Anlage schlingenförmig gerafften Stauchung gegenübergestellt, die später vom Eis überprägt worden ist. Die Lagebeziehungen beider Stauchmoränen zu den Bruchstrukturen im präquartären Untergrund der Region und zu deren neotektonischen Mobilität werden diskutiert. Die glazigene Stauchung bei Peski wird dem Sosch-(Warthe-)eis zugeschrieben, die auf Jasmund der Weichselvereisung. Beide Stauchungen sind nach dem Höhepunkt einer Vereisung, nach der maximalen Eisausbreitung, erfolgt. Diese rückläufigen Kälteperioden boten besonders günstige Voraussetzungen für Einwirkungen des Inlandeises auf den Untergrund., research