Early Pathways Therapy for Young Children in Poverty: A Randomized Controlled Trial

Early Pathways is a home-based, parent and child therapy program for the treatment of disruptive behaviors among young children living in poverty. In this study, 199 clinically referred children were randomly assigned to an immediate treatment (IT) or wait-list control (WL) conditions. Results indicated that parents in the IT condition reported significant improvements in their child’s disruptive and prosocial behaviors and increased nurturing and decreased use of corporal and verbal punishment by their parents compared to the WL families. Gains were maintained for children in both the IT and WL conditions at 3-month follow-up

Charged spin 1/2 particle in an arbitrary magnetic field in two spatial dimensions: a supersymmetric quantum mechanical system

It is shown that the 2 X 2 matrix Hamiltonian describing the dynamics of a charged spin 1/2 particle with g-factor 2 moving in an arbitrary, spatially dependent, magnetic field in two spatial dimensions can be written as the anticommuator of a nilpotent operator and its hermitian conjugate. Consequently, the Hamiltonians for the two different spin projections form partners of a supersymmetric quantum mechanical system. The resulting supersymmetry algebra can then be exploited to explicitly construct the exact zero energy ground state wavefunction for the system. Modulo this ground state, the remainder of the eigenstates and eigenvalues of the two partner Hamiltonians form positive energy degenerate pairs. We also construct the spatially asymptotic form of the magnetic field which produces a finite magnetic flux and associated zero energy normalizable ground state wavefunction.Comment: 10 pages, LaTe

Multistability of free spontaneously-curved anisotropic strips

Multistable structures are objects with more than one stable conformation, exemplified by the simple switch. Continuum versions are often elastic composite plates or shells, such as the common measuring tape or the slap bracelet, both of which exhibit two stable configurations: rolled and unrolled. Here we consider the energy landscape of a general class of multistable anisotropic strips with spontaneous Gaussian curvature. We show that while strips with non-zero Gaussian curvature can be bistable, strips with positive spontaneous curvature are always bistable, independent of the elastic moduli, strips of spontaneous negative curvature are bistable only in the presence of spontaneous twist and when certain conditions on the relative stiffness of the strip in tension and shear are satisfied. Furthermore, anisotropic strips can become tristable when their bending rigidity is small. Our study complements and extends the theory of multistability in anisotropic shells and suggests new design criteria for these structures.Comment: 20 pages, 10 figure

Net energy analysis of solar and conventional domestic hot water systems in Melbourne, Australia

It is commonly assumed that solar hot water systems save energy and reduce greenhouse gas emissions. Very rarely has the life-cycle energy requirements of solar hot water systems been analysed, including their embodied energy. The extent to which solar hot water systems save energy compared to conventional systems in Melbourne, Australia, is shown through a comparative net energy analysis. The solar systems provided a net energy saving compared to the conventional systems after 0.5 to 2 years, for electricity and gas systems respectively.<br /

Instantons, supersymmetric vacua, and emergent geometries

We study instanton solutions and superpotentials for the large number of vacua of the plane-wave matrix model and a 2+1 dimensional Super Yang-Mills theory on $R\times S^2$ with sixteen supercharges. We get the superpotential in the weak coupling limit from the gauge theory description. We study the gravity description of these instantons. Perturbatively with respect to a background, they are Euclidean branes wrapping cycles in the dual gravity background. Moreover, the superpotential can be given by the energy of the electric charge system characterizing each vacuum. These charges are interpreted as the eigenvalues of matrices from a reduction for the 1/8 BPS sector of the gauge theories. We also discuss qualitatively the emergence of the extra spatial dimensions appeared on the gravity side.Comment: 29 pages, 3 figures, latex. v2: references added, comments added. v3: accepted version in PR

Why P/OF should look for evidences of over-dense structures in solar flare hard X-ray sources

White-light and hard X-ray (HXR) observations of two white-light flares (WLFs) show that if the radiative losses in the optical continuum are powered by fast electrons directly heating the WLF source, then the column density constraints imposed by the finite range of the electrons requires that the WLF consist of an over-dense region in the chromosphere, with density exceeding 10 to the 14th power/cu cm. Thus, we recommend that P/OF search for evidences of over-dense structures in HXR images obtained simultaneously with optical observations of flares

Starsat: A space astronomy facility

Preliminary design and analyses of a versatile telescope for Spacelab missions are presented. The system is an all-reflective Korsch three-mirror telescope with excellent performance characteristics over a wide field and a broad spectral range, making it particularly suited for ultraviolet observations. The system concept is evolved around the utilization of existing hardware and designs which were developed for other astronomy space projects

Spin observables and the determination of the parity of Θ+\Theta^+ in photoproduction reactions

Spin observables in the photoproduction of the $\Theta^+$ are explored for the purpose of determining the parity of the $\Theta^+$. Based on reflection symmetry in the scattering plane, we show that certain spin observables in the photoproduction of the $\Theta^+$ can be related directly to its parity. We also show that measurements of both the target nucleon asymmetry and the $\Theta^+$ polarization may be useful in determining the parity of $\Theta^+$ in a model-independent way. Furthermore, we show that no combination of spin observables involving only the polarization of the photon and/or nucleon in the initial state can determine the parity of $\Theta^+$ unambiguously.Comment: LaTeX, 11 pages, minor revisio

Organized condensation of worm-like chains

We present results relevant to the equilibrium organization of DNA strands of arbitrary length interacting with a spherical organizing center, suggestive of DNA-histone complexation in nucleosomes. We obtain a rich phase diagram in which a wrapping state is transformed into a complex multi-leafed, rosette structure as the adhesion energy is reduced. The statistical mechanics of the "melting" of a rosette can be mapped into an exactly soluble one-dimensional many-body problem.Comment: 15 pages, 2 figures in a pdf fil