2,139 research outputs found

    Fulfilling the promise of applied developmental science: Is it time to reconsider our approach?

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    The promise of applied developmental science is that we can use scientific methods to promote positive human development and improve the lives of children and families. However, the present political environment in the United States makes the creation of research-informed federal policy difficult, even when the evidence supporting a given policy is unequivocal. In this essay, we hope to begin a conversation about how we, as applied developmental scientists, may modify our approach in order to best fulfill the promise of applied developmental science. To begin this conversation, we discuss the potential for establishing long-term partnerships with smaller entities, including state and municipal governments and non-governmental organizations to narrow the gap between what we know about children and families and the policies and programs that impact them. This \u27bottom-up\u27 approach has a long lineage in applied developmental science, and is currently enjoying a renaissance through the burgeoning interest in researcher-practitioner partnerships. Whether implicitly or explicitly, these partnerships often incorporate a systems perspective on children\u27s development; here, we review why embracing a systems perspective may increase the likelihood of crafting policies and programs that can improve the lives of children and families

    Magnon Mediated Electric Current Drag Across a Ferromagnetic Insulator Layer

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    In a semiconductor hererostructure, the Coulomb interaction is responsible for the electric current drag between two 2D electron gases across an electron impenetrable insulator. For two metallic layers separated by a ferromagnetic insulator (FI) layer, the electric current drag can be mediated by a nonequilibrium magnon current of the FI. We determine the drag current by using the semiclassical Boltzmann approach with proper boundary conditions of electrons and magnons at the metal-FI interface.Comment: 13 pages, 2 figures: to appear in PR

    The 492 GHz emission of Sgr A* constrained by ALMA

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    We report linearly polarized continuum emission properties of Sgr A* at \sim492 GHz, based on the Atacama Large Millimeter Array (ALMA) observations. We used the observations of the likely unpolarized continuum emission of Titan, and the observations of C\textsc{i} line emission, to gauge the degree of spurious polarization. The Stokes I flux of 3.6±\pm0.72 Jy during our run is consistent with extrapolations from the previous, lower frequency observations. We found that the continuum emission of Sgr A* at \sim492 GHz shows large amplitude differences between the XX and the YY correlations. The observed intensity ratio between the XX and YY correlations as a function of parallactic angle may be explained by a constant polarization position angle of \sim158^{\circ}±\pm3^{\circ}. The fitted polarization percentage of Sgr A* during our observational period is 14\%±\pm1.2\%. The calibrator quasar J1744-3116 we observed at the same night can be fitted to Stokes I = 252 mJy, with 7.9\%±\pm0.9\% polarization in position angle P.A. = 4.1^{\circ}±\pm4.2^{\circ}. The observed polarization percentage and polarization position angle in the present work appear consistent with those expected from longer wavelength observations in the period of 1999-2005. In particular, the polarization position angle at 492 GHz, expected from the previously fitted 167^{\circ}±\pm7^{\circ} intrinsic polarization position angle and (-5.6±\pm0.7)×\times105^{5} rotation measure, is 1558+9^{+9}_{-8}, which is consistent with our new measurement of polarization position angle within 1σ\sigma. The polarization percentage and the polarization position angle may be varying over the period of our ALMA 12m Array observations, which demands further investigation with future polarization observations.Comment: 10 pages, 6 figures, 1st referee report received and revise

    An Ecological Systems Perspective on Individual Differences in Children\u27s Performance on Measures of Executive Function

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    The predictive validity of performance on cognitive-behavioral measures of executive function (EF) suggests that these measures index children\u27s underlying capacity for self-regulation. In this paper, we apply ecological systems theory to critically evaluate this assertion. We argue that as typically administered, standard measures of EF do not index children\u27s underlying, trait-like capacity for EF, but rather assess their state-like EF performance at a given point in time and in a particular (and often quite peculiar) context. This underscores the importance of disentangling intra-individual (i.e., state-like) and inter-individual (trait-like) differences in performance on these measures and understanding how factors at various levels of organization may contribute to both. To this end, we offer an approach that combines the collection of repeated measures of EF with a multilevel modeling framework, and conclude by discussing the application of this approach to the study of educational interventions designed to foster children\u27s EF

    Improving Highway Work Zone Safety

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    Highway work zones disrupt normal traffic flow and can create severe safety problems. Due to the rising needs in highway maintenance and construction in the United States, the number of work zones is increasing nationwide. With a total of 1,010 fatalities and more than 40,000 injuries occurring in 2006, improvements in work zone safety are necessary. The three primary objectives of this research project included: 1) to determine the effectiveness of a Portable Changeable Message Sign (PCMS) in reducing vehicle speeds on two-lane, rural highway work zones; 2) to determine the effectiveness of a Temporary Traffic Sign (TTS), (W20-1, “Road Work Ahead”); and 3) to determine motorists’ responses to the signage. To accomplish these objectives, field experiments were conducted at US-36 and US-73 in Seneca and Hiawatha, Kansas, respectively. During the field experiments, an evaluation of the effectiveness of the PCMS was conducted under three different conditions: 1) PCMS on; 2) PCMS off, but still visible; and 3) PCMS removed from the road and out of sight. The researchers also divided the vehicles into three classes (passenger car, truck, and semitrailer) and compared the mean speed change of these classes based on three different sign setups: PCMS on, PCMS off, and the use of the TTS (W20-1, “Road Work Ahead”). A survey was also conducted at the experimental work zones to obtain a general understanding of the motorists’ attitudes as they traveled through the construction areas. Based on the data analysis results, researchers concluded that the presence of the PCMS effectively reduced vehicle speeds on two-lane highway work zones. A slow speed is more likely to reduce the probability of a crash or the severity of a crash. In addition, researchers performed a univariate analysis of the variance test to determine if a significant interaction existed between motorists’ responses and the sign conditions. The results showed a significant interaction between the signs and passenger car vehicles

    Thermal Links for the Implementation of an Optical Refrigerator

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    Optical refrigeration has been demonstrated by several groups of researchers, but the cooling elements have not been thermally linked to realistic heat loads in ways that achieve the desired temperatures. The ideal thermal link will have minimal surface area, provide complete optical isolation for the load, and possess high thermal conductivity. We have designed thermal links that minimize the absorption of fluoresced photons by the heat load using multiple mirrors and geometric shapes including a hemisphere, a kinked waveguide, and a tapered waveguide. While total link performance is dependent on additional factors, we have observed net transmission of photons with the tapered link as low as 0.04%. Our optical tests have been performed with a surrogate source that operates at 625 nm and mimics the angular distribution of light emitted from the cooling element of the Los Alamos solid state optical refrigerator. We have confirmed the optical performance of our various link geometries with computer simulations using CODE V optical modeling software. In addition we have used the thermal modeling tool in COMSOL MULTIPHYSICS to investigate other heating factors that affect the thermal performance of the optical refrigerator. Assuming an ideal cooling element and a nonabsorptive dielectric trapping mirror, the three dominant heating factors are (1) absorption of fluoresced photons transmitted through the thermal link, (2) blackbody radiation from the surrounding environment, and (3) conductive heat transfer through mechanical supports. Modeling results show that a 1 cm3 load can be chilled to 107 K with a 100Wpump laser. We have used the simulated steady-state cooling temperatures of the heat load to compare link designs and system configurations

    The discovery of potent, selective, and reversible inhibitors of the house dust mite peptidase allergen Der p 1: an innovative approach to the treatment of allergic asthma.

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    Blocking the bioactivity of allergens is conceptually attractive as a small-molecule therapy for allergic diseases but has not been attempted previously. Group 1 allergens of house dust mites (HDM) are meaningful targets in this quest because they are globally prevalent and clinically important triggers of allergic asthma. Group 1 HDM allergens are cysteine peptidases whose proteolytic activity triggers essential steps in the allergy cascade. Using the HDM allergen Der p 1 as an archetype for structure-based drug discovery, we have identified a series of novel, reversible inhibitors. Potency and selectivity were manipulated by optimizing drug interactions with enzyme binding pockets, while variation of terminal groups conferred the physicochemical and pharmacokinetic attributes required for inhaled delivery. Studies in animals challenged with the gamut of HDM allergens showed an attenuation of allergic responses by targeting just a single component, namely, Der p 1. Our findings suggest that these inhibitors may be used as novel therapies for allergic asthma

    Diagnosis and management of antiretroviral-therapy failure in resource-limited settings in sub-Saharan Africa: challenges and perspectives.

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    Despite the enormous progress made in scaling up antiretroviral therapy (ART) in sub-Saharan Africa, many challenges remain, not least of which are the identification and management of patients who have failed first-line therapy. Less than 3% of patients are receiving second-line treatment at present, whereas 15-25% of patients have detectable viral loads 12 months or more into treatment, of whom a substantial proportion might have virological failure. We discuss the reasons why virological ART failure is likely to be under-diagnosed in the routine health system, and address the current difficulties with standard recommended second-line ART regimens. The development of new diagnostic tools for ART failure, in particular a point-of-care HIV viral-load test, combined with simple and inexpensive second-line therapy, such as boosted protease-inhibitor monotherapy, could revolutionise the management of ART failure in resource-limited settings

    Brief of Tribal Nations and Indian Organizations as Amici Curiae in Support of the Navajo Nation, U.S. Supreme Court Docket No. 21-1484

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    SUMMARY OF ARGUMENT: The Winters Doctrine recognizes and gives effect to the promises made by the United States in treaties, congressionally ratified agreements, and executive orders that Tribal Nations would retain permanent and viable homelands. These promises, made in exchange for the Tribal Nations’ cession of billions of acres of land, paved the way for the non-Indian settlement of the West. Although every tribal homeland is unique, invariably, each requires water to be livable. Applying the canons of construction this Court has developed as part of its federal Indian law jurisprudence, as well as the history and circumstances surrounding the creation of each individual reservation, the Winters Doctrine holds that the United States promised to provide water sufficient to fulfill the purposes for which the reservations were created. Concomitant with the promise to reserve water rights is the corresponding duty to protect and deliver on that promise and avoid rendering those rights meaningless through obstruction, depletion, or diversion to more junior users. In this way, the Winters Doctrine is a pathway for ensuring the United States fulfills its solemn obligations to Tribal Nations. The United States—through both Congress and the Executive—has repeatedly and expressly reaffirmed its understanding of these obligations. Petitioners here articulate no reason why the Lower Colorado River Basin should be treated differently. This Court should once again ensure the United States honors its obligations. In the 115 years since Winters v. United States, the Doctrine solidified into an integral part of the fabric that makes up Western water management. The Winters Doctrine forms the basis for extensive adjudication and settlement of claims by Tribal Nations to water rights. Today, millions of tribal and non-tribal citizens benefit from the certainty provided by the Winters Doctrine
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