143,613 research outputs found
Gang Innovation, Patriarchy and Powerlessness : Expanding Theory To Relfect [Reflect] American Politics
When cities grew large enough to develop slums, gangs began to form. The heritage of gang behavior is poverty and its children: abuse, alcoholism, and drug addiction, to name a few. Today we are facing a problem of major proportions in our cities. Gang membership is seemingly growing with no end in sight, and a beleaguered nation, a struggling city, the mother of a gang member all ask: Why? There are probably several answers and more questions. This paper is an attempt to understand the problem of gang delinquency by utilizing already existing theory. Robert Merton\u27s Strain Theory lends itself to the discussion of gang delinquency; however, this paper will expand on the theory and link it to the powerlessness of young minority males and patriarchal ideology
Understanding the Debate Over Necessity: Unanswered Questions and Future Implications of Annulments in the Argentine Gas Cases
This paper analyses possible effects on total employment, and the distribution between agency work and regular contracts as a consequence of the Swedish implementation of the EU Temporary and Agency Workers Directive in a dual labour market Mortensen-Pissarides search model. The directive states that the basic working and employment conditions for agency workers should be equal to those for a comparable employee at the client firm, and that all parties should actively facilitate the transition from agency employment to employment directly at the client firm. Even though the results suggest a negative net effect on total employment, the implementation is shown to have a positive impact on overall welfare, and that an increased transition probability from the agency sector into regular employment would contribute even more
Puerto Ricans: White or Non- White?
The question of race and racial identity among Puerto Ricans has been one of great confusion and misunderstanding. The confusion and misunderstanding exist both among Puerto Ricans and Anglo-Americans. This is a study of the paradox of race perceptions among mainland-bred and island-bred Puerto Ricans. This study was undertaken to look at several related issues: What are the racial perceptions and attitudes held by Puerto Ricans, both on the island and the continental mainland? Further, to what extent has Americanization of Puerto Ricans affected those perceptions and attitudes? Likewise, what role does class consciousness and class mobility play? How do Anglo-American racial perceptions and attitudes affect the Puerto Rican\u27s image of self? And finally, do individual variables such as one\u27s skin color, ethnic identity or pride, personal prejudices or family background further affect these perceptions and attitudes
Uncertainties inherent in the decomposition of a Transformation
This contribution adds to the points on the <indeterminacy of special
relativity> made by De Abreu and Guerra. We show that the Lorentz
Transformation can be composed by the physical observations made in a frame K
of events in a frame K-prime viz i) objects in K-prime are moving at a speed v
relative to K, ii) distances and time intervals measured by K-prime are at
variance with those measured by K and iii) the concept of simultaneity is
different in K-prime compared to K. The order in which the composition is
executed determines the nature of the middle aspect (ii). This essential
uncertainty of the theory can be resolved only by a universal synchronicity as
discussed in [1] based on the unique frame in which the one way speed of light
is constant in all directions.Comment: 10 pages including an appendix. Published in the European Journal of
Physics as a Comment. Eur. J. Phys. 29 (2008) L13-L1
Ergodic Properties of Infinite Harmonic Crystals: an Analytic Approach
We give through pseudodifferential operator calculus a proof that the quantum
dynamics of a class of infinite harmonic crystals becomes ergodic and mixing
with respect to the quantum Gibbs measure if the classical infinite dynamics is
respectively ergodic and mixing with respect to the classical infinite Gibbs
measure. The classical ergodicity and mixing properties are recovered as
, and the infinitely many particles limits of the quantum Gibbs
averages are proved to be the averages over a classical infinite Gibbs measure
of the symbols generating the quantum observables under Weyl quantization.Comment: 30 pages, plain LaTe
Critical measures, quadratic differentials, and weak limits of zeros of Stieltjes polynomials
We investigate the asymptotic zero distribution of Heine-Stieltjes
polynomials - polynomial solutions of a second order differential equations
with complex polynomial coefficients. In the case when all zeros of the leading
coefficients are all real, zeros of the Heine-Stieltjes polynomials were
interpreted by Stieltjes as discrete distributions minimizing an energy
functional. In a general complex situation one deals instead with a critical
point of the energy. We introduce the notion of discrete and continuous
critical measures (saddle points of the weighted logarithmic energy on the
plane), and prove that a weak-* limit of a sequence of discrete critical
measures is a continuous critical measure. Thus, the limit zero distributions
of the Heine-Stieltjes polynomials are given by continuous critical measures.
We give a detailed description of such measures, showing their connections with
quadratic differentials. In doing that, we obtain some results on the global
structure of rational quadratic differentials on the Riemann sphere that have
an independent interest.Comment: 70 pages, 14 figures. Minor corrections, to appear in Comm. Math.
Physic
Wide Field Observations of the Ursa Minor dSph galaxy
Ursa Minor (UMi) is one of the closest satellites of the Milky Way (d=69
kpc). It is possibly a disrupted dSph interacting with the external Galactic
halo. This makes its study quite necessary in the forementioned context. In
this paper we present preliminary results of a wide field photometry survey of
UMi and discuss the presence of an intermediate-age population and tidal tails
in it.Comment: 4 pages, 5 figures, to appear in the IAU Symp.192 Proceeding
Biocatalytic Route to Chiral Precursors of β-Substituted-γ-Amino Acids
In this work, we utilized commercial lipases (from Thermomyces lanuginosa, Rhizopus delemar, and Mucor miehei) as biocatalysts for the efficient synthesis of precursors of β-substituted-γ-amino acids. This biocatalytic route provides a practical and efficient synthesis of a wide range of optically active compounds by accepting a number of aliphatic and aromatic 3-substituted-3-cyano-2-(ethoxycarbonyl)propanoic acid ethyl esters (2) without compromising enantioselectivity or yields. The resolution step allows for the nearly quantitative recovery of the unreacted enantiomer of R-(2) as well as the newly formed 3-substituted-3-cyano-2-(ethoxycarbonyl)propanoic acid (3) in high enantio and diastereoselectivity. The use of a facile thermal decarboxylation of (3) in aqueous solution to produce 3-substituted-3-cyanopropanoic acid ethyl esters (4) enable us to prepare a wide range of optically active precursors of β-Substituted-γ-Amino Acids
Magnetoplasmons excitations in graphene for filling factors
In the frame of the Hartree-Fock approximation, the dispersion of
magnetoplasmons in Graphene is derived for all types of transitions for filling
factors . The optical conductivity components of the magnetoplasmon
curves are calculated. It is shown that the electron-electron interactions lead
to a strong re-normalization of the apparent Fermi velocity of Graphene which
is different for different types of transitions.Comment: 15 pages, 7 figure
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