3,572 research outputs found

    Gentrification and the Economic and Housing Crises of the 2000’s: A Critical Analysis of Government-Sponsored Enterprises and Predatory Lenders

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    2013 dissertation for MBA in International Business. Selected by academic staff as a good example of a masters level dissertation. This study focuses on gentrification and the possible correlations with the economic and housing crises as well as the economic activity and mortgage market structure of Fannie Mae and Freddie Mac. The theories in this thesis are quantitative, and at times qualitative, and relate to financial, cultural, and organizational theories in the real estate market. The research methodology is both positivist primary and secondary in nature, and the two are used in union in order to attain a higher level of knowledge of the topic, and show correlations with the aforementioned factors and gentrification. The following sections, data analysis, conclusion and recommendation use the collection of research in order to formulate a focused and unbiased argument that shows a correlation of various factors to gentrification. Finally, further research on the influences of Fannie Mae and Freddie Mac and their policies is recommended for future managers and academics interested in gentrification

    Auroral Energy Input from Energetic Electrons and Joule Heating at Chatanika

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    With the incoherent scatter radar at Chatanika, Alaska, a wide variety of measurements can be made related to the ionosphere, magnetosphere, and neutral atmosphere. A significant parameter is the amount of energy transferred from the magnetosphere into the ionosphere and neutral atmosphere during periods of auroral activity. In this report we examine a procedure whereby the incident energy flux of auroral electrons is ascertained from radar measurements. As part of the process we compare radar-determined fluxes with those ascertained from simultaneous photometric observations at 4278 Å. The fluxes obtained by both techniques had similar magnitudes and time variations. If we assume that the largest uncertainty in the radar/photometer comparison is the effective recombination coefficient, then that coefficient can also be deduced. We find a value 3 × 10−7 cm³/s at about 105 km, which is in good agreement with other recent determinations during active auroral conditions. We then combine this technique with one to ascertain the Joule heating to determine the energy input from the magnetosphere to the ionosphere in a region localized above the radar on March 22, 1973, in the midnight sector. The energy input is continuous at a significant level, i.e., greater than the 3 ergs/cm² s that could be delivered by the sun, were it overhead. Moreover, at times, each of these inputs became as great as 30 ergs/cm² s

    High cooperativity coupling of electron-spin ensembles to superconducting cavities

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    Electron spins in solids are promising candidates for quantum memories for superconducting qubits because they can have long coherence times, large collective couplings, and many quantum bits can be encoded into the spin-waves of a single ensemble. We demonstrate the coupling of electron spin ensembles to a superconducting transmission-line resonator at coupling strengths greatly exceeding the cavity decay rate and comparable to spin linewidth. We also use the enhanced coupling afforded by the small cross-section of the transmission line to perform broadband spectroscopy of ruby at millikelvin temperatures at low powers. In addition, we observe hyperfine structure in diamond P1 centers and time domain saturation-relaxation of the spins.Comment: 4pgs, 4 figure

    Stationary states of an electron in periodic structures in a constant uniform electrical field

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    On the basis of the transfer matrix technique an analytical method to investigate the stationary states, for an electron in one-dimensional periodic structures in an external electrical field, displaying the symmetry of the problem is developed. These solutions are shown to be current-carrying. It is also shown that the electron spectrum for infinite structures is continuous, and the corresponding wave functions do not satisfy the symmetry condition of the problem.Comment: 10 pages (Latex), no figures, in the revised variant some mistakes in the English text are corrected and also the first two paragraphs in the Conclusion are refined (Siberian physical-technical institute at the Tomsk state university, Tomsk, Russia

    Cardioprotection by cocoa polyphenols and ω-3 fatty acids: A disease-prevention perspective on aging-associated cardiovascular risk

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    Cardiovascular disease (CVD) remains the leading cause of death today. Many of the biochemical alterations associated with the pathophysiology of CVD can be modified by adequate intakes of bioactive nutrients through a correct diet or supplementation. Recently, there has been growing public and clinical interest in cocoa polyphenols (CPs) and omega-3 (ω-3) fatty acids. A plethora of nutritional intervention trials and experimental studies demonstrates that consumption of these bioactive food compounds is beneficial to promote cardiovascular health. The purpose of this review is to summarize the major cardioprotective effects of CPs and ω-3 fatty acids, providing a scientific rationale for incorporating the combination of these molecules as a nutritional intervention in the prevention of CVD. Although several studies have shown the individual cardioprotective nature of these compounds, a combination treatment with CPs and ω-3 fatty acids may be a promising approach to enhance the preventive value of these molecules and reduce cardiovascular risk factors associated with aging. Therefore, this article also reviews some of the key studies on the interaction between CPs and the metabolism of ω-3 fatty acids

    Omega-3 PUFAs and vitamin D co-supplementation as a safe-effective therapeutic approach for core symptoms of autism spectrum disorder: case report and literature review

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    Introduction: Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by abnormal development of cognitive, social, and communicative skills. Although ASD aetiology and pathophysiology are still unclear, various nutritional factors have been investigated as potential risk factors for ASD development, including omega-3 polyunsaturated fatty acids (PUFAs) and vitamin D deficiency. In fact, both omega-3 PUFAs and vitamin D are important for brain development and function. Case report: Herein, we report the case of a 23-year-old young adult male with autism who was referred to our Unit due to a 12-month history of cyclic episodes of restlessness, agitation, irritability, oppositional and self-injurious behaviours. Laboratory tests documented a markedly altered omega-6/omega-3 balance, along with a vitamin D deficiency, as assessed by serum levels of 25-hydroxyvitamin D. Omega-3 and vitamin D co-supplementation was therefore started, with remarkable improvements in ASD symptoms throughout a 24-month follow-up period. A brief review of the literature for interventional studies evaluating the efficacy of omega-3 or vitamin D supplementation for the treatment of ASD-related symptoms is also provided. Conclusion: To our knowledge, this is the first case reporting remarkable beneficial effects on ASD symptoms deriving from omega-3 and vitamin D combination therapy. This case report suggests omega-3 and vitamin D co-supplementation as a potential safe-effective therapeutic strategy to treat core symptoms of ASD. However, larger studies are needed to evaluate the real efficacy of such therapeutic approach in a broader sample of ASD patients

    Spin waves and spin-state transitions in a ruthenate high-temperature antiferromagnet

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    Ruthenium compounds play prominent roles in materials research ranging from oxide electronics to catalysis, and serve as a platform for fundamental concepts such as spin-triplet superconductivity, Kitaev spin-liquids, and solid-state analogues of the Higgs mode in particle physics. However, basic questions about the electronic structure of ruthenates remain unanswered, because several key parameters (including the Hund's-rule, spin-orbit, and exchange interactions) are comparable in magnitude, and their interplay is poorly understood - partly due to difficulties in synthesizing sizable single crystals for spectroscopic experiments. Here we introduce a resonant inelastic x-ray scattering (RIXS) technique capable of probing collective modes in microcrystals of 4d4d-electron materials. We present a comprehensive set of data on spin waves and spin-state transitions in the honeycomb antiferromagnet SrRu2_{2}O6_{6}, which possesses an unusually high N\'eel temperature. The new RIXS method provides fresh insight into the unconventional magnetism of SrRu2_{2}O6_{6}, and enables momentum-resolved spectroscopy of a large class of 4d4d transition-metal compounds.Comment: The original submitted version of the published manuscript. https://www.nature.com/articles/s41563-019-0327-

    Precision Measurement of the n-3He Incoherent Scattering Length Using Neutron Interferometry

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    We report the first measurement of the low-energy neutron-3^3He incoherent scattering length using neutron interferometry: bi′=(−2.512±0.012statistical±0.014systematic)b_i' = (-2.512\pm 0.012{statistical}\pm0.014{systematic}) fm. This is in good agreement with a recent calculation using the AV18+3N potential. The neutron-3^3He scattering lengths are important for testing and developing nuclear potential models that include three nucleon forces, effective field theories for few-body nuclear systems, and neutron scattering measurements of quantum excitations in liquid helium. This work demonstrates the first use of a polarized nuclear target in a neutron interferometer.Comment: 4 figure

    Crystal structure and high-field magnetism of La2CuO4

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    Neutron diffraction was used to determine the crystal structure and magnetic ordering pattern of a La2CuO4 single crystal, with and without applied magnetic field. A previously unreported, subtle monoclinic distortion of the crystal structure away from the orthorhombic space group Bmab was detected. The distortion is also present in lightly Sr-doped crystals. A refinement of the crystal structure shows that the deviation from orthorhombic symmetry is predominantly determined by displacements of the apical oxygen atoms. An in-plane magnetic field is observed to drive a continuous reorientation of the copper spins from the orthorhombic b-axis to the c-axis, directly confirming predictions based on prior magnetoresistance and Raman scattering experiments. A spin-flop transition induced by a c-axis oriented field previously reported for non-stoichiometric La2CuO4 is also observed, but the transition field (11.5 T) is significantly larger than that in the previous work

    Managing the Socially Marginalized: Attitudes Towards Welfare, Punishment and Race

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    Welfare and incarceration policies have converged to form a system of governance over socially marginalized groups, particularly racial minorities. In both of these policy areas, rehabilitative and social support objectives have been replaced with a more punitive and restrictive system. The authors examine the convergence in individual-level attitudes concerning welfare and criminal punishment, using national survey data. The authors\u27 analysis indicates a statistically significant relationship between punitive attitudes toward welfare and punishment. Furthermore, accounting for the respondents\u27 racial attitudes explains the bivariate relationship between welfare and punishment. Thus, racial attitudes seemingly link support for punitive approaches to opposition to welfare expenditures. The authors discuss the implications of this study for welfare and crime control policies by way of the conclusion
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