Study of the Mechanisms of Flux Pinning in Type 2 Superconductors

Flux pinning mechanisms in type-2 semiconductors and specific heat measurements on annealed and deformed pure niobium sample

The role of metaphor in shaping the identity and agenda of the United Nations: the imagining of an international community and international threat

This article examines the representation of the United Nations in speeches delivered by its Secretary General. It focuses on the role of metaphor in constructing a common ‘imagining’ of international diplomacy and legitimising an international organisational identity. The SG legitimises the organisation, in part, through the delegitimisation of agents/actions/events constructed as threatening to the international community and to the well-being of mankind. It is a desire to combat the forces of menace or evil which are argued to motivate and determine the organisational agenda. This is predicated upon an international ideology of humanity in which difference is silenced and ‘working towards the common good’ is emphasised. This is exploited to rouse emotions and legitimise institutional power. Polarisation and antithesis are achieved through the employment of metaphors designed to enhance positive and negative evaluations. The article further points to the constitutive, persuasive and edifying power of topic and situationally-motivated metaphors in speech-making

Pamela: development of the RF system for a non-relativistic non-scaling FFAG

The PAMELA project(Particle Accelerator For MEdical Applications) currently consists of the design of a particle therapy facility. The project, which is in the design phase, contains Non-Scaling FFAG, particle accelerator capable of rapid beam acceleration, giving a pulse repetition rate of 1kHz, far beyond that of a conventional synchrotron. To realise the repetition rate, a key component of the accelerator is the rf accelerating system. The combination of a high energy gain per turn and a high repetition rate is a significant challenge. In this paper, options for the rf system of the proton ring and the status of development are presented

Traveling interface modulations and anisotropic front propagation in ammonia oxidation over Rh(110)

The bistable NH3 + O2 reaction over a Rh(110) surface was explored in the pressure range 10−6 -10−3 mbar and in the temperature range 300-900 K using photoemission electron microscopy and low energy electron microscopy as spatially resolving methods. We observed a history dependent anisotropy in front propagation, traveling interface modulations, transitions with secondary reaction fronts, and stationary island structures.Fil: Rafti, Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina. Universidad Nacional de La Plata; Argentina. Leibniz-Universität Hannover; AlemaniaFil: Borkenhagen, Benjamin. Technische Universität Clausthal; AlemaniaFil: Lilenkamp, Gerhard. Technische Universität Clausthal; AlemaniaFil: Lovis, Florian. Leibniz-Universität Hannover; AlemaniaFil: Smolinsky, Tim. Leibniz-Universität Hannover; AlemaniaFil: Imbihl, Roland. Leibniz-Universität Hannover; Alemani

Eutectic Colony Formation: A Stability Analysis

Experiments have widely shown that a steady-state lamellar eutectic solidification front is destabilized on a scale much larger than the lamellar spacing by the rejection of a dilute ternary impurity and forms two-phase cells commonly referred to as `eutectic colonies'. We extend the stability analysis of Datye and Langer for a binary eutectic to include the effect of a ternary impurity. We find that the expressions for the critical onset velocity and morphological instability wavelength are analogous to those for the classic Mullins-Sekerka instability of a monophase planar interface, albeit with an effective surface tension that depends on the geometry of the lamellar interface and, non-trivially, on interlamellar diffusion. A qualitatively new aspect of this instability is the occurence of oscillatory modes due to the interplay between the destabilizing effect of the ternary impurity and the dynamical feedback of the local change in lamellar spacing on the front motion. In a transient regime, these modes lead to the formation of large scale oscillatory microstructures for which there is recent experimental evidence in a transparent organic system. Moreover, it is shown that the eutectic front dynamics on a scale larger than the lamellar spacing can be formulated as an effective monophase interface free boundary problem with a modified Gibbs-Thomson condition that is coupled to a slow evolution equation for the lamellar spacing. This formulation provides additional physical insights into the nature of the instability and a simple means to calculate an approximate stability spectrum. Finally, we investigate the influence of the ternary impurity on a short wavelength oscillatory instability that is already present at off-eutectic compositions in binary eutectics.Comment: 26 pages RevTex, 14 figures (28 EPS files); some minor changes; references adde

Co-enrollment for Child Health: How Receipt and Loss of Food and Housing Subsidies Relate to Housing Security and Statutes for Streamlined, Multi-Subsidy Application

In light of recent policy debates around funding food and housing subsidies, the combined influence of these programs on housing security (HS), defined as housing without crowding or frequent moves, remains unstudied. In a multi-city study of young children, federal nutrition and housing subsidies together increased the odds of HS, whereas loss of nutrition subsidies lowered the odds of HS even after controlling for housing subsidy receipt. Ensuring eligible families’ access to both nutrition and housing subsidies may sustain HS. The results of this study inform and support current efforts by states to streamline online applications for social services and remove statutory legal barriers to accessing these subsidies simultaneously

Trends in Household and Child Food Insecurity Among Families with Young Children from 2007 to 2013

Background: 2007-2013 spanned an economic downturn with rising food costs. While Supplemental Nutrition Assistance Program (SNAP) benefits increased during those years by 13.6% from the 2009 American Recovery Reinvestment Act (ARRA), the impact of these competing conditions on household food insecurity (HFI, household food insecure but child food secure) and child food insecurity (CFI, household and child food insecure) in households with infants and toddlers has not been investigated. Objective: To describe HFI and CFI in households participating in SNAP vs. households likely eligible but not participating (No SNAP). Design: Repeat cross-sectional Participants/Setting: 19,999 caregivers of childrenChildren’s HealthWatch survey in emergency and primary care departments in 5 US cities. Main Outcome Measures: The 18-item U.S. Household Food Security Survey (HFSS) measured HFI (≥3 affirmative responses on non-child-specific questions) and CFI (≥2 affirmative responses to eight child-specific questions). Statistical analyses performed: The sample was stratified by SNAP/ No SNAP. Multinomial logistic regression analyses examined the association between SNAP receipt and HFI and CFI. Results: Across the study period, controlling for confounders including year, households with SNAP were 17% less likely to experience HFI (AOR 0.83; 95% CI,0 .75, 0.91; p Conclusions: Receipt of SNAP vs. No SNAP was associated with decreased prevalence of HFI and CFI during much of the economic downturn; this impact waned as the buying power of the boost in benefit amounts during the ARRA period eroded

Plasmacytoid Precursor Dendritic Cells From NOD Mice Exhibit Impaired Function : Are They a Component of Diabetes Pathogenesis?

OBJECTIVE—Plasmacytoid precursor dendritic cell facilitating cells (p-preDC FCs) play a critical role in facilitation of syngeneic and allogeneic hematopoietic stem cell (HSC) engraftment. Here, we evaluated the phenotype and function of CD8+/TCR− FCs from NOD mice