1,873 research outputs found

    Employers Can Do Youth Development Too

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    Professionals and volunteers who care about the welfare of young people know the importance of caring adults. The field has worked with all types of adults, including parents, teachers, and youth workers to enhance their understanding of youth development philosophy, approaches and practices. However, we’ve virtually ignored an entire sector of adults who play a major role in the lives of young people—employers. Given the large number of youth in the workforce, and understanding the critical role of caring adults, the question becomes, “how do we focus attention on preparing employers and other workplace adults to be more thoughtful and intentional about their interactions with young people?” The objective of this paper is to lay out the relevant issues and to begin the dialogue about building the capacity of employers to better support the development of our young people

    Development Strategies for Online Volunteer Training Modules: A Team Approach

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    Volunteers are central to the delivery of 4-H programs, and providing quality, relevant training is key to volunteer success. Online, asynchronous modules are an enhancement to a training delivery menu for adult volunteers, providing consistent, accessible options traditionally delivered primarily face to face. This article describes how Minnesota 4-H focuses on a team approach to the intentional instructional design process used to develop interactive and engaging asynchronous training modules for adult volunteers. The roles and responsibilities of the team members are described along with how this method expedites module development, increases quality, and minimizes costs

    Employers Can Do Youth Development Too

    Get PDF
    Professionals and volunteers who care about the welfare of young people know the importance of caring adults. The field has worked with all types of adults, including parents, teachers, and youth workers to enhance their understanding of youth development philosophy, approaches and practices. However, we’ve virtually ignored an entire sector of adults who play a major role in the lives of young people—employers. Given the large number of youth in the workforce, and understanding the critical role of caring adults, the question becomes, “how do we focus attention on preparing employers and other workplace adults to be more thoughtful and intentional about their interactions with young people?” The objective of this paper is to lay out the relevant issues and to begin the dialogue about building the capacity of employers to better support the development of our young people

    Logic Gates and Ring Oscillators Based on Ambipolar Nanocrystalline-Silicon TFTs

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    Nanocrystalline silicon (nc-Si) thin film transistors (TFTs) are well suited for circuit applications that require moderate device performance and low-temperature CMOS-compatible processing below 250°C. Basic logic gate circuits fabricated using ambipolar nc-Si TFTs alone are presented and shown to operate with correct outputs at frequencies of up to 100 kHz. Ring oscillators consisting of nc-Si TFT-based inverters are also shown to operate at above 20 kHz with a supply voltage of 5 V, corresponding to a propagation delay of 5 V for several hours

    Longitudinal Effects of the Family Support Program Chancenreich on Parental Involvement and the Language Skills of Preschool Children

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    When they enter primary school children already vary significantly in their language skills, depending at least in part on their family’s social background. In particular, the home learning environment plays a significant role in children’s development. For that reason, early intervention programs have been developed to obviate learning difficulties and to promote health, children’s development, and educational equality. The family support program Chancenreich aims to encourage the interaction and relationship between parents and children through two different course formats. The present study examines the longitudinal effects of attending the Chancenreich program and different course formats on (a) parents attending further educational services for children after completing the program, (b) children’s vocabulary and level of grammar development at the age of 5 and (c) the children’s vocabulary development between the ages of 3 and 5. Furthermore, we examine the relationship between family characteristics and the attendance rates of different course formats of the Chancenreich program at the first and second point of measurement. The study follows a longitudinal design with two points of measurements (T1: Mage = 41 months, T2: Mage = 68 months), and a sample size of 121 parents and their children at T2 in the intervention group and 41 parents and their children in the comparison group. Findings indicate that attendance of the Chancenreich program’s courses is related to child and family characteristics and to later patterns of course participation after completing the program. Further, both children’s level of vocabulary skills (PPVT) at the age of 5 and their development between the ages of 3 and 5 benefit from the parental participation in parenting skills training at the age of 3. Implications and future research on the effectiveness of family support programs are discussed

    Fast minimum variance wavefront reconstruction for extremely large telescopes

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    We present a new algorithm, FRiM (FRactal Iterative Method), aiming at the reconstruction of the optical wavefront from measurements provided by a wavefront sensor. As our application is adaptive optics on extremely large telescopes, our algorithm was designed with speed and best quality in mind. The latter is achieved thanks to a regularization which enforces prior statistics. To solve the regularized problem, we use the conjugate gradient method which takes advantage of the sparsity of the wavefront sensor model matrix and avoids the storage and inversion of a huge matrix. The prior covariance matrix is however non-sparse and we derive a fractal approximation to the Karhunen-Loeve basis thanks to which the regularization by Kolmogorov statistics can be computed in O(N) operations, N being the number of phase samples to estimate. Finally, we propose an effective preconditioning which also scales as O(N) and yields the solution in 5-10 conjugate gradient iterations for any N. The resulting algorithm is therefore O(N). As an example, for a 128 x 128 Shack-Hartmann wavefront sensor, FRiM appears to be more than 100 times faster than the classical vector-matrix multiplication method.Comment: to appear in the Journal of the Optical Society of America

    Jet propulsion without inertia

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    A body immersed in a highly viscous fluid can locomote by drawing in and expelling fluid through pores at its surface. We consider this mechanism of jet propulsion without inertia in the case of spheroidal bodies, and derive both the swimming velocity and the hydrodynamic efficiency. Elementary examples are presented, and exact axisymmetric solutions for spherical, prolate spheroidal, and oblate spheroidal body shapes are provided. In each case, entirely and partially porous (i.e. jetting) surfaces are considered, and the optimal jetting flow profiles at the surface for maximizing the hydrodynamic efficiency are determined computationally. The maximal efficiency which may be achieved by a sphere using such jet propulsion is 12.5%, a significant improvement upon traditional flagella-based means of locomotion at zero Reynolds number. Unlike other swimming mechanisms which rely on the presentation of a small cross section in the direction of motion, the efficiency of a jetting body at low Reynolds number increases as the body becomes more oblate, and limits to approximately 162% in the case of a flat plate swimming along its axis of symmetry. Our results are discussed in the light of slime extrusion mechanisms occurring in many cyanobacteria

    Spatio-Temporal Pattern Recognition in Neural Circuits with Memory-Transistor-Driven Memristive Synapses

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    Spiking neural circuits have been designed in which the memristive synapses exhibit spike timing-dependent plasticity (STDP). STDP is a learning mechanism where synaptic weight (the strength of the connection between two neurons) depends on the timing of pre-and post-synaptic action potentials. A known capability of networks with STDP is detection of simultaneously recurring patterns within the population of afferent neurons. This work uses SPICE (simulation program with integrated circuit emphasis) to demonstrate the spatio-temporal pattern recognition (STPR) effect in networks with 25 afferent neurons. The neuron circuits are the leaky integrate-and-fire (I&F) type and implemented using extensively validated ambipolar nano-crystalline silicon (nc-Si) thin-film transistors (TFT) models. Ideal memristor synapses are driven by a nanoparticle memory thin-film transistor (np-TFT) with a short retention time attached to each neuron circuit output. This device serves to temporally modulate the conductance path from post-synaptic neurons, providing rate-based and timing-dependent learning. With this configuration, the use of a crossbar structures would also be possible, providing dense synaptic connections and potentially reduced energy consumption

    The “Peer-Effect” in Counterterrorist Policies

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    AbstractExisting accounts posit that defensively oriented counterterrorist policies create negative externalities and result in regulatory competition that induces governments to increasingly tighten their policies. We argue that rather than causing an unconditional global “race to the top,” spatial dependence in counterterrorist policies is limited to within groups of countries exposed to a similar level of threat from international terrorism. Countries strongly differ in their propensity to become the target of an international terror attack. Governments can safely ignore counterterrorist policies enacted by countries outside their “peer group,” but they must pay attention to measures undertaken by their peers. We test several predictions derived from our theory in an empirical analysis of counterterrorist regulations in twenty Western developed-country democracies over the period 2001 to 2008.</jats:p
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