MeV ion scattering from thin Si single crystals: A novel approach to interface studies

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Vortex Plasma in a Superconducting Film with Magnetic Dots

We consider a superconducting film, placed upon a magnetic dot array. Magnetic moments of the dots are normal to the film and randomly oriented. We determine how the concentration of the vortices in the film depends on the magnetic moment of a dot at low temperatures. The concentration of the vortices, bound to the dots, is proportional to the density of the dots and depends on the magnetization of a dot in a step-like way. The concentration of the unbound vortices oscillates about a value, proportional to the magnetic moment of the dots. The period of the oscillations is equal to the width of a step in the concentration of the bound vortices.Comment: RevTeX, 4 page

Lattice dynamics and reduced thermal conductivity of filled skutterudites

The great reduction in thermal conductivity of skutterudites upon filling the ``void'' sites with Rare Earth (RE) ions is key to their favorable thermoelectric properties but remains to be understood. Using lattice dynamic models based on first principles calculations, we address the most popular microscopic mechanism, reduction via rattling ions. The model withstands inelastic neutron scattering and specific heat measurements, and refutes hypotheses of an anharmonic RE potential and of two distinct localized RE vibrations of disparate frequencies. It does indicate a strong hybridization between bare La vibrations and certain Sb-like phonon branches, suggesting anharmonic scattering by harmonic RE motions as an important mechanism for suppression of heat conductivity.Comment: modified version resubmitted to PRB. Results unchanged, text changed substantiall

Electrical Manipulation of Nanomagnets

We demonstrate a possibility to manipulate the magnetic coupling between two nanomagnets with a help of ac electric field. In the scheme suggested the magnetic coupling in question is mediated by a magnetic particle contacting with both of the nanomagnets through the tunnel barriers. The electric field providing a successive suppression of the barriers leads to pumping of magnetization through the mediating particle. Time dependent dynamics of the particle magnetization allows to to switch between ferro- and antiferromagnetic couplings.Comment: 4 pages, 2 figure

Preferências nutricionais entre adolescentes da classe média de Manaus, AM (Brazil)

INTRODUÇÃO: O Brasil tem sido considerado um País em transição nutricional em razão dos recentes aumentos na prevalência de obesidade e doenças crônicas na classe média, sendo importante identificar os fatores que influenciam as preferências nutricionais desse grupo. Foi realizado estudo com estudantes de classe média de um colégio secundário, particular, em Manaus, AM, Brasil. Com o objetivo de determinar a disponibilidade e a acessibilidade das merendas e analisar as atitudes e preferências dos estudantes e a influência de vários fatores na escolha de merendas nutritivas. MÉTODOS: O estudo incluiu quatros fases: (a) discusão em um grupo de especialistas em nutrição sobre a disponibilidade e acessibilidade das merendas em Manaus; (b) inquérito junto a um grupo dos adolescentes (n=63) sobre suas preferências e hábitos nutricionais; (c) inquérito junto a supermercados selecionado para identificar a disponibilidade e acessibilidade das merendas preferidas; (d) um grupo acompanhado de uma subamostra dos adolescentes (n=55) para identificar a preferências e atitudes sobre o custo e disponibilidade das merendas. RESULTADOS: Foi constatado que os estudantes possuíam condições financeiras para comprar merendas e que as merendas nutritivas não custam mais do que as não nutritivas. A preferência dos adolescentes foi por merendas não nutritivas. Os fatores que, principalmente, influenciam na escolha originam-se da família e da televisão. CONCLUSÃO: As implicações para futuras pesquisas e programas nutricionais são discutidos, recomendando-se campanha de educação nutricional para famílias, visto a importância desta na escolha de merendas entre esses adolescentes.INTRODUCTION: Brazil has been called a nation in nutrition transitional because of recent increases in the prevalence of obesity and related chronic diseases. With overweight conditions already prevalent among middle-income populations, there exists a need to identify factors that influence nutrition behavior within this group. OBJECTIVE: To address this subject, a research study was implemented among middle-class adolescents attending a large private secondary school in Manaus, Amazonas, Brazil. The study determined the availability and accessibility of snack foods as well as subjects’ attitudes and preferences towards, and the influence of family and friends on healthy (high-nutrient density) snack choices. METHODS: The 4-stage process included: (a) a nutrition expert focus group discussion that reported local nutrition problems in general and factors related to adolescent nutrition, (b) an adolescent pilot survey (n=63) that solicited information about snacking preferences and habits as well as resources for nutrition information and snack money; (c) a survey of various area food market sources to determine the availability and accessibility of high nutrient density snacks; and (d) a follow-up adolescent survey (n=55) that measured snack food preferences and perceptions about their cost and availability. RESULTS: Results included the finding that, although affordable high nutrient density snacks were available, preferences for low nutrient density snacks prevailed. The adolescents were reportedly more likely to be influenced by and obtain nutrition information from family members than friends. CONCLUSION: From study results it is apparent that a focus on food availability will not automatically result in proper nutritional practices among adolescents. This fact and the parental influence detected are evidence of a need to involve adolescents and their parents in nutrition education campaigns to improve adolescent snack food choices

Quasi-long range order in glass states of impure liquid crystals, magnets, and superconductors

In this review we consider glass states of several disordered systems: vortices in impure superconductors, amorphous magnets, and nematic liquid crystals in random porous media. All these systems can be described by the random-field or random-anisotropy O(N) model. Even arbitrarily weak disorder destroys long range order in the O(N) model. We demonstrate that at weak disorder and low temperatures quasi-long range order emerges. In quasi-long-range-ordered phases the correlation length is infinite and correlation functions obey power dependencies on the distance. In pure systems quasi-long range order is possible only in the lower critical dimension and only in the case of Abelian symmetry. In the presence of disorder this type of ordering turns out to be more common. It exists in a range of dimensions and is not prohibited by non-Abelian symmetries.Comment: 32 page

Rectification in Luttinger liquids

We investigate the rectification of an ac bias in Luttinger liquids in the presence of an asymmetric potential (the ratchet effect). We show that strong repulsive electron interaction enhances the ratchet current in comparison with Fermi liquid systems, and the I-V curve is strongly asymmetric in the low-voltage regime even for a weak asymmetric potential. At higher voltages the ratchet current exhibits an oscillatory voltage dependence.Comment: 5 pages, Revte

Explaining the effects of symptom attribution by carers on help-seeking for individuals living with dementia

This study investigated the effects of carer attributions on help-seeking behaviour for people with dementia using interviews with 84 carers recruited through general practice. Memory loss was the most commonly reported first symptom but psychological and behavioural symptoms were also common at onset. In over a third of individuals help-seeking was delayed for a mean of 25 months (range 6-69, SD 19.3). Help-seeking between those who attributed symptoms to dementia, or to unknown causes, and those who attributed symptoms to personality, ageing, life events or other illnesses was statistically significant ( p < 0.001). No statistically significant associations between help-seeking and patient or carer characteristics were found. There is a need to raise public awareness about the range of symptoms suggestive of dementia. Assumptions that age and other conditions may be the likely cause of an individual's cognitive decline needs to be challenged by practitioners. Attribution of symptoms to characteristics other than dementia delays help-seeking

Crisaborole Ointment Improves Quality of Life of Patients with Mild to Moderate Atopic Dermatitis and Their Families.

IntroductionThe impact of crisaborole ointment, a nonsteroidal phosphodiesterase 4 inhibitor for the treatment of mild to moderate atopic dermatitis (AD), on quality of life (QoL) was assessed in two identically designed phase 3 studies (AD-301: NCT02118766; AD-302: NCT02118792, both at http://www.clinicaltrials.gov ).MethodsIn both studies, patients aged ≥ 2 years with mild to moderate AD per the Investigator's Static Global Assessment were randomly assigned 2:1 to receive crisaborole or vehicle twice daily for 28 days. QoL was assessed using the Children's Dermatology Life Quality Index (CDLQI) (2-15 years), the Dermatology Life Quality Index (DLQI) (≥ 16 years), and the Dermatitis Family Impact Questionnaire (DFI) (parents/caregivers/family of patients aged 2-17 years). Established QoL score severity bands provided clinical context.ResultsGreater mean improvement in QoL was observed in crisaborole-treated patients than in vehicle-treated patients at day 29 [mean change from baseline (∆BL), CDLQI: - 4.6 vs. - 3.0; P &lt; 0.001; DLQI: - 5.2 vs. - 3.5; P = 0.015]. At baseline, more than half the patients had a "moderate effect" or higher of AD on QoL. At day 29, there was a trend toward more crisaborole- than vehicle-treated patients having "small effect" to "no effect", The QoL of parents/caregivers/family improved more for crisaborole-treated than for vehicle-treated patients (∆BL, DFI: - 3.7 vs. - 2.7; P = 0.003).ConclusionCrisaborole treatment results in clinically meaningful improvement in QoL for patients and their parents/caregivers/families.Trial registrationAD-301: http://www.clinicaltrials.gov , NCT02118766; AD-302: http://www.clinicaltrials.gov , NCT02118792.FundingAnacor Pharmaceuticals, Inc., a wholly owned subsidiary of Pfizer Inc., New York, NY

First Principles Study of Zn-Sb Thermoelectrics

We report first principles LDA calculations of the electronic structure and thermoelectric properties of $\beta$-Zn$_{4}$Sb$_{3}$. The material is found to be a low carrier density metal with a complex Fermi surface topology and non-trivial dependence of Hall concentration on band filling. The band structure is rather covalent, consistent with experimental observations of good carrier mobility. Calculations of the variation with band filling are used to extract the doping level (band filling) from the experimental Hall number. At this band filling, which actually corresponds to 0.1 electrons per 22 atom unit cell, the calculated thermopower and its temperature dependence are in good agreement with experiment. The high Seebeck coefficient in a metallic material is remarkable, and arises in part from the strong energy dependence of the Fermiology near the experimental band filling. Improved thermoelectric performance is predicted for lower doping levels which corresponds to higher Zn concentrations.Comment: 5 pages, 6 figure