Suggested approaches to writing songs at the primary and elementary levels

Thesis (M.Ed.)--Boston Universit

Polarization immunity of magnetoresistivity response under Microwave excitation

We analyze theoretically the dependence of the microwave polarization sate and sense on the magnetoresistivity response of two-dimensional electron systems. Linear and circular polarization have been considered with different senses and directions. We discuss the polarization dependence of the longitudinal magnetoresistivity and propose an explanation for the experimentally observed polarization immunity, i.e., resistivity oscillations and zero resistance state regions are unaffected by the sense of circular polarization or by the direction of microwave electric field.Comment: 4 pages and 1 figur

Random parking, Euclidean functionals, and rubber elasticity

We study subadditive functions of the random parking model previously analyzed by the second author. In particular, we consider local functions $S$ of subsets of $\mathbb{R}^d$ and of point sets that are (almost) subadditive in their first variable. Denoting by $\xi$ the random parking measure in $\mathbb{R}^d$, and by $\xi^R$ the random parking measure in the cube $Q_R=(-R,R)^d$, we show, under some natural assumptions on $S$, that there exists a constant $\bar{S}\in \mathbb{R}$ such that % $$\lim_{R\to +\infty} \frac{S(Q_R,\xi)}{|Q_R|}\,=\,\lim_{R\to +\infty}\frac{S(Q_R,\xi^R)}{|Q_R|}\,=\,\bar{S}$$ % almost surely. If $\zeta \mapsto S(Q_R,\zeta)$ is the counting measure of $\zeta$ in $Q_R$, then we retrieve the result by the second author on the existence of the jamming limit. The present work generalizes this result to a wide class of (almost) subadditive functions. In particular, classical Euclidean optimization problems as well as the discrete model for rubber previously studied by Alicandro, Cicalese, and the first author enter this class of functions. In the case of rubber elasticity, this yields an approximation result for the continuous energy density associated with the discrete model at the thermodynamic limit, as well as a generalization to stochastic networks generated on bounded sets.Comment: 28 page

Embryogenic responses of Vitis spp.: Effects of genotype and polyvinylpyrrolidone

Somatic embryos were obtained from leaf discs excised from cv. Seyve Villard 5276 (Vitis sp.) and from a Brazilian interspecific hybrid derived from Madalena (Vitis sp.) and Magnolia (V. rotundifolia). Experimental procedures were conducted according to HARST (1995) except that phenylalanine was replaced by polyvinylpyrrolidone which improved the embryogenic response of cultivar SV-5276. Standard somatic embryogenesis was confirmed by histological and ultrastructural analysis which also revealed teratological embryonic development. Secondary embryos were observed and documented by scanning microscop

Search for an exosphere in sodium and calcium in the transmission spectrum of exoplanet 55 Cancri e

[Abridged] The aim of this work is to search for an absorption signal from exospheric sodium (Na) and singly ionized calcium (Ca$^+$) in the optical transmission spectrum of the hot rocky super-Earth 55 Cancri e. Although the current best-fitting models to the planet mass and radius require a possible atmospheric component, uncertainties in the radius exist, making it possible that 55 Cancri e could be a hot rocky planet without an atmosphere. High resolution (R$\sim$110000) time-series spectra of five transits of 55 Cancri e, obtained with three different telescopes (UVES/VLT, HARPS/ESO 3.6m & HARPS-N/TNG) were analysed. Targeting the sodium D lines and the calcium H and K lines, the potential planet exospheric signal was filtered out from the much stronger stellar and telluric signals, making use of the change of the radial component of the orbital velocity of the planet over the transit from -57 to +57 km/sec. Combining all five transit data sets, we detect a signal potentially associated with sodium in the planet exosphere at a statistical significance level of 3$\sigma$. Combining the four HARPS transits that cover the calcium H and K lines, we also find a potential signal from ionized calcium (4.1 $\sigma$). Interestingly, this latter signal originates from just one of the transit measurements - with a 4.9$\sigma$ detection at this epoch. Unfortunately, due to the low significance of the measured sodium signal and the potentially variable Ca$^+$ signal, we estimate the p-values of these signals to be too high (corresponding to <4$\sigma$) to claim unambiguous exospheric detections. By comparing the observed signals with artificial signals injected early in the analysis, the absorption by Na and Ca$^+$ are estimated to be at a level of approximately 2.3$\times 10^{-3}$ and 7.0$\times 10^{-2}$ respectively, relative to the stellar spectrum.Comment: 15 pages, 8 figures, submission updated after English language editing, submission updated to correct a mistaken cross-reference noticed in A&A proo

Comparative morpho-anatomical studies of the lesions caused by citrus leprosis virus on sweet orange

The leprosis disease shows a viral etiology and the citrus leprosis virus is considered its etiologic agent. The disease may show two types of cytopatologic symptom caused by two virus: nuclear (CiLV-N) and cytoplasmic (CiLV-C) types. The aim of this study was to compare the morpho-anatomical differences in the lesions caused by leprosis virus-cytoplasmic and nuclear types in Citrus sinensis (L.) Osbeck ?Pêra?. Leaf and fruit lesions were collected in Piracicaba/São Paulo (cytoplasmic type) and Monte Alegre do Sul/São Paulo and Amparo/São Paulo (nuclear type). The lesions were photographed and then fixed in Karnovsky solution, dehydrated in a graded ethylic series, embedded in hydroxy-ethyl methacrylate resin (Leica Historesin), sectioned (5?m thick), stained and mounted in synthetic resin. The digital images were acquired in a microscope with digital video camera. Leaf and fruit lesions caused by the two viruses were morphologically distinct. Only the lesion caused by CiLV-N virus presented three well-defined regions. In both lesions there was the accumulation of lipidic substances in necrotic areas that were surrounded by cells with amorphous or droplets protein. Only leaf and fruit lesions caused by CiLV-N virus exhibited traumatic gum ducts in the vascular bundles.Disponivel em: .Acesso em: 18 out. 2010

Strategies for tackling Taenia solium taeniosis/cysticercosis: A systematic review and comparison of transmission models, including an assessment of the wider Taeniidae family transmission models

Background: The cestode Taenia solium causes the neglected (zoonotic) tropical disease cysticercosis, a leading cause of preventable epilepsy in endemic low and middle-income countries. Transmission models can inform current scaling-up of control efforts by helping to identify, validate and optimise control and elimination strategies as proposed by the World Health Organization (WHO). Methodology/Principal findings: A systematic literature search was conducted using the PRISMA approach to identify and compare existing T. solium transmission models, and related Taeniidae infection transmission models. In total, 28 modelling papers were identified, of which four modelled T. solium exclusively. Different modelling approaches for T. solium included deterministic, Reed-Frost, individual-based, decision-tree, and conceptual frameworks. Simulated interventions across models agreed on the importance of coverage for impactful effectiveness to be achieved. Other Taeniidae infection transmission models comprised force-of-infection (FoI), population-based (mainly Echinococcus granulosus) and individual-based (mainly E. multilocularis) modelling approaches. Spatial structure has also been incorporated (E. multilocularis and Taenia ovis) in recognition of spatial aggregation of parasite eggs in the environment and movement of wild animal host populations. Conclusions/Significance: Gaps identified from examining the wider Taeniidae family models highlighted the potential role of FoI modelling to inform model parameterisation, as well as the need for spatial modelling and suitable structuring of interventions as key areas for future T. solium model development. We conclude that working with field partners to address data gaps and conducting cross-model validation with baseline and longitudinal data will be critical to building consensus-led and epidemiological setting-appropriate intervention strategies to help fulfil the WHO targets. Author summary: Taenia solium infection in humans (taeniosis and neurocysticercosis) and pigs (cysticercosis) presents a significant global public health and economic challenge. The World Health Organization has called for validated strategies and wider consensus on which strategies are suitable for different epidemiological settings to support successful T. solium control and elimination efforts. Transmission models can be used to inform these strategies. Therefore, a modelling review was undertaken to assess the current state and gaps relating to T. solium epidemiological modelling. The literature surrounding models for other Taeniidae family infections was also considered, identifying approaches to aid further development of existing T. solium models. A variety of different modelling approaches have been used for T. solium including differences in structural and parametric assumptions associated with T. solium transmission biology. Despite these differences, all models agreed on the importance of coverage on intervention effectiveness. Other Taeniidae family models highlighted the need for incorporating spatial structure when necessary to capture aggregation of transmission stages in the environment and movement of animal hosts

Valorization of local almond genotypes regarding their biochemical and mineral composition: abstract

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Seroprevalence of Hepatitis B and C Viruses among Human Immunodeficiency Virus Infected Patients Accessing Healthcare in Federal Medical Centre, Keffi, Nigeria

Infections of Hepatitis B and C viruses among seropositive Human immunodeficiency virus patients are a growing public health problem in Sub Saharan Africa characterized by unaffordable treatment, severe morbidity and associated mortality. This study was aimed at evaluating the seroprevalence of Hepatitis B and C viruses among HIV infected patients accessing health care at Federal Medical Centre, Keffi, Nigeria. The cross-sectional study took place between May-July 2016. A total of 200 blood samples were collected from HIV patients after informed consent and self-administered questionnaires were completed. The samples were centrifuged and the serum screened for HBV and HCV using the immunochromatographic technique. A general prevalence of infection with hepatitis B and C viruses in the study population was 17.5%. The prevalence of HBV infection was 12.5% while HCV was 5.0%. Females have higher infection rates for both viruses (p > 0.05). HBV infection was highest among those aged 20-29 years (14.3%) and lowest among those aged 30-39 years (6.5%). HCV infection was highest among those aged > 40 years (8.7%) and least among those aged 30-39 years (0.0%). Infection rates with blood transfusion, smoking habit, scarification marks and alcohol intake as risk factors were more for HBV than HCV (p > 0.05). The HIV/HBV and HIV/HCV coinfection prevalence of 12.5% and 5.0% respectively is a cause for concern. This finding underscores the urgent need for more proactive HBV immunization programs and screening of HIV patients for HBV and HCV before and even during antiretroviral therapy. Health education against these silent killers should also be advocated

Applying the Information-Motivation-Behavioral Skills Model of HIV- Risk to Youth in Psychiatric Care

This study examined the utility of cognitive and behavioral constructs (AIDS in-formation, motivation, and behavioral skills) in explaining sexual risk taking among 172 12–20–year-old ethnically diverse urban youths in outpatient psy-chiatric care. Structural equation modeling revealed only moderate support for the model, explaining low to moderate levels of variance in global sexual risk taking. The amount of explained variance improved when age was included as a predictor in the model. Findings shed light on the contribution of AIDS informa-tion, motivation, and behavioral skills to risky sexual behavior among teens re-ceiving outpatient psychiatric care. Results suggest that cognitive and behavioral factors alone may not explain sexual risk taking among teens whose cognitive and emotional deficits (e.g., impaired judgment, poor reality testing, affect dysregulation) interfere with HIV preventive behavior. The most powerful ex-planatory model will likely include a combination of cognitive, behavioral, developmental, social (e.g., family), and personal (e.g., psychopathology) risk mechanisms