Early Introduction of Computer Science Education in Minority Youth: A New Representation of Tomorrow\u27s Engineers?

Computer Science (CS) has a large underrepresentation of females and racial minority (Hispanic and African American) populations in today’s education intuitions and workforce. Public health workers and companies have reviewed the consequences of this underrepresentation. Although a promise to incorporate more STEM education in schools the large gap is still prevalent. The Google Code Corps (GCC) is a partnership between The Boys & Girls Clubs of America (BGCA), AmeriCorps, and Google with a symbiotic goal to impact minorities and low-socioeconomic (SES) communities through education, mentoring, and capacity building. GCC project aims to empower BGC members by developing a successful and sustainable CS program. The completion of GCC year-one findings resulted in more ethnic minorities partaking CS classes and an overall increase in CS concepts. In summary, 44% of BGCSV participants were female and 70% were ethnic minorities. Students who partook in classes felt they could have a career in computer science. Furthermore, staff demonstrated a feeling that CS First was an easy and well-structured program. Multiple internal and external factors including allostatic load and a leaky pipeline contribute to a large underrepresentation of minorities in CS. Implementing CS education early and through multiple layers of the Social Ecological Model (SEM) shows promise for an increased interest. Programs like the GCC can create long-term improvements and set up student success through capacity building activities. However, proper mentorship and continuing assessments and motivating are necessary for overall program success and creating a sustainable impact on both minorities and the CS workforce

What's on job seekers' social media sites? A content analysis and effects of structure on recruiter judgments and predictive validity

Many organizational representatives review social media (SM) information (e.g., Facebook, Twitter) when recruiting and assessing job applicants. Despite this, very little empirical data exist concerning the SM information available to organizations or whether assessments of such information are a valid predictor of work outcomes. This multistudy investigation examines several critical issues in this emerging area. In Study 1, we conducted a content analysis of job seekers' Facebook sites (n = 266) and found that these sites often provide demographic variables that U.S. employment laws typically prohibit organizations from using when making personnel decisions (e.g., age, ethnicity, and religion), as well as other personal information that is not work-related (e.g., sexual orientation, marital status). In Study (n = 140), we examined whether job seekers' SM information is related to recruiter evaluations. Results revealed that various types of SM information correlated with recruiter judgments of hireability, including demographic variables (e.g.. gender, marital status), variables organizations routinely assess (e.g.. education. training, and skills). and variables that may be a concern to organizations (e.g., profanity. sexual behavior). In Study 3 (ta = 81), we examined whether structuring SM assessments (e.g., via rater training) affects criterion-related validity. Results showed that structuring SM assessments did not appear to improve the prediction of future job performance or withdrawal intentions. Overall, the present findings suggest that organizations should be cautious about assessing SM information during the staffing process

Impact of the earthworm Lumbricus terrestris (L.) on As, Cu, Pb and Zn mobility and speciation in contaminated soils

To assess the risks that contaminated soils pose to the environment properly a greater understanding of how soil biota influence the mobility of metal(loid)s in soils is required. Lumbricus terrestris L. were incubated in three soils contaminated with As, Cu, Pb and Zn. The concentration and speciation of metal(loid)s in pore waters and the mobility and partitioning in casts were compared with earthworm-free soil. Generally the concentrations of water extractable metal(loid)s in earthworm casts were greater than in earthworm-free soil. The impact of the earthworms on concentration and speciation in pore waters was soil and metal specific and could be explained either by earthworm induced changes in soil pH or soluble organic carbon. The mobilisation of metal(loid)s in the environment by earthworm activity may allow for leaching or uptake into biota

Hydrodynamic transport functions from quantum kinetic theory

Starting from the quantum kinetic field theory [E. Calzetta and B. L. Hu, Phys. Rev. D37, 2878 (1988)] constructed from the closed-time-path (CTP), two-particle-irreducible (2PI) effective action we show how to compute from first principles the shear and bulk viscosity functions in the hydrodynamic-thermodynamic regime. For a real scalar field with $\lambda \Phi ^{4}$ self-interaction we need to include 4 loop graphs in the equation of motion. This work provides a microscopic field-theoretical basis to the ``effective kinetic theory'' proposed by Jeon and Yaffe [S. Jeon and L. G. Yaffe, Phys. Rev. D53, 5799 (1996)], while our result for the bulk viscosity reproduces their expression derived from linear response theory and the imaginary-time formalism of thermal field theory. Though unavoidably involved in calculations of this sort, we feel that the approach using fundamental quantum kinetic field theory is conceptually clearer and methodically simpler than the effective kinetic theory approach, as the success of the latter requires clever rendition of diagrammatic resummations which is neither straightforward nor failsafe. Moreover, the method based on the CTP-2PI effective action illustrated here for a scalar field can be formulated entirely in terms of functional integral quantization, which makes it an appealing method for a first-principles calculation of transport functions of a thermal non-abelian gauge theory, e.g., QCD quark-gluon plasma produced from heavy ion collisions.Comment: 25 pages revtex, 11 postscript figures. Final version accepted for publicatio

The Singlet Majoron Model with Hidden Scale Invariance

We investigate an extension of the Singlet Majoron Model in which the breaking of dilatation symmetry by the mass parameters of the scalar potential is removed by means of a dilaton field. Starting from the one-loop renormalization group improved potential, we discuss the ground state of the theory. The flat direction in the classical potential is lifted by quantum corrections and the true vacua are found. Studying the finite temperature potential, we analyze the cosmological consequences of a Jordan-Brans-Dicke dilaton and show that the lepton number is spontaneously broken after the electroweak phase transition, thus avoiding any constraint coming from the requirement of the preservation of the baryon asymmetry in the early Universe. We also find that, contrary to the Standard Model case, the dilaton cosmology does not impose any upper bound on the scale of the spontaneous breaking of scale invariance.Comment: 22 pages, SISSA-5/93/A and DFPD/93/TH/0

Пути инновационного развития Автономной Республики Крым

Целью работы является изучение состояния и перспектив дальнейшего развития инновационной активности в Автономной Республике Крым

The Real Symplectic Groups in Quantum Mechanics and Optics

text of abstract (We present a utilitarian review of the family of matrix groups $Sp(2n,\Re)$, in a form suited to various applications both in optics and quantum mechanics. We contrast these groups and their geometry with the much more familiar Euclidean and unitary geometries. Both the properties of finite group elements and of the Lie algebra are studied, and special attention is paid to the so-called unitary metaplectic representation of $Sp(2n,\Re)$. Global decomposition theorems, interesting subgroups and their generators are described. Turning to $n$-mode quantum systems, we define and study their variance matrices in general states, the implications of the Heisenberg uncertainty principles, and develop a U(n)-invariant squeezing criterion. The particular properties of Wigner distributions and Gaussian pure state wavefunctions under $Sp(2n,\Re)$ action are delineated.)Comment: Review article 43 pages, revtex, no figures, replaced because somefonts were giving problem in autometic ps generatio

Ergodic properties of a generic non-integrable quantum many-body system in thermodynamic limit

We study a generic but simple non-integrable quantum {\em many-body} system of {\em locally} interacting particles, namely a kicked $t-V$ model of spinless fermions on 1-dim lattice (equivalent to a kicked Heisenberg XX-Z chain of 1/2 spins). Statistical properties of dynamics (quantum ergodicity and quantum mixing) and the nature of quantum transport in {\em thermodynamic limit} are considered as the kick parameters (which control the degree of non-integrability) are varied. We find and demonstrate {\em ballistic} transport and non-ergodic, non-mixing dynamics (implying infinite conductivity at all temperatures) in the {\em integrable} regime of zero or very small kick parameters, and more generally and important, also in {\em non-integrable} regime of {\em intermediate} values of kicked parameters, whereas only for sufficiently large kick parameters we recover quantum ergodicity and mixing implying normal (diffusive) transport. We propose an order parameter (charge stiffness $D$) which controls the phase transition from non-mixing/non-ergodic dynamics (ordered phase, $D>0$) to mixing/ergodic dynamics (disordered phase, D=0) in the thermodynamic limit. Furthermore, we find {\em exponential decay of time-correlation function} in the regime of mixing dynamics. The results are obtained consistently within three different numerical and analytical approaches: (i) time evolution of a finite system and direct computation of time correlation functions, (ii) full diagonalization of finite systems and statistical analysis of stationary data, and (iii) algebraic construction of quantum invariants of motion of an infinite system, in particular the time averaged observables.Comment: 18 pages in REVTeX with 14 eps figures included, Submitted to Physical Review

Chelating N-heterocyclic carbene-carboranes offer flexible ligand coordination to IrIII, RhIII and RuII: effect of ligand cyclometallation in catalytic transfer hydrogenation

Imidazolium salts linked by an ethyl tether to closo-dicarbadodecaboranes were reacted with [IrCp*Cl2]2, [RhCp*Cl2]2 or [Ru(p-cymene)Cl2]2 in the presence of Ag2O to prepare complexes of the type [MCp*(NHC)Cl2] (M = Ir, Rh; NHC = N-heterocyclic carbene) or [Ru(p-cymene)(NHC)Cl2]. When the NHC contained an N-tBu substituent, C–H activation of the tBu and subsequent alkyl coordination was observed at Ir. Coordination of the closo-dicarbadodecaborane moiety to Ir was possible to give 7-membered metallacycles, coordinated through the carbenic carbon of the NHC and either a carbon atom or a boron atom of the carborane. Examination of the Ir complexes in the transfer hydrogenation of acetophenone to 1-phenylethanol reveals that cyclometallation of the carborane moiety is important for catalytic efficacy, indicating a bifunctional mechanism and involvement of the dicarbadodecaborane anion