Operator ordering for generally covariant systems

The constraint operators belonging to a generally covariant system are found out within the framework of the BRST formalism. The result embraces quadratic Hamiltonian constraints whose potential can be factorized as a never null function times a gauge invariant function. The building of the inner product between physical states is analyzed for systems featuring either intrinsic or extrinsic time.Comment: 4 pages. Talk given at the Third Conference on "Constrained Dynamics and Quantum Gravity" held in Sardinia (Italy), September 1999. Journal reference:Nucl. Phys. B (Proc. Suppl.) 88 (2000) 322-32

An Integrated Ecological-Social Simulation Model of Farmer Decisions and Cropping System Performance in the Rolling Pampas (Argentina)

Changes in agricultural systems are a multi-causal process involving climate change, globalization and technological change. These complex interactions regulate the landscape transformation process by imposing land use and cover change (LUCC) dynamics. In order to better understand and forecast the LUCC process we developed a spatially explicit agent-based model in the form of a Cellular Automata: the AgroDEVS model. The model was designed to project viable LUCC dynamics along with their associated economic and environmental changes. AgroDEVS is structured with behavioral rules and functions representing a) crop yields, b) weather conditions, c) economic profits, d) farmer preferences, e) adoption of technology levels and f) natural resource consumption based on embodied energy accounting. Using data from a typical location of the Pampa region (Argentina) for the period 1988-2015, simulation exercises showed that economic goals were achieved, on average, each 6 out of 10 years, but environmental thresholds were only achieved in 1.9 out of 10 years. In a set of 50-years simulations, LUCC patterns converge quickly towards the most profitable crop sequences, with no noticeable trade-off between economic and environmental conditions.Fil: Pessah, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Ferraro, Diego Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Blanco, Daniela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; ArgentinaFil: Castro, Rodrigo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentin

Treatment of pagetoid reticulosis with intensity modulated radiation therapy

Pagetoid reticulosis, also known as Woringer-Kolopp disease, is a rare variant of cutaneous T-cell lymphoma usually presenting as an isolated patch or plaque on the extremities.  Immunohistochemical staining of T-cell markers can be variable, but as the name implies the epidermotropic lymphocytes consistently display a “pagetoid” appearance.  The following case demonstrates clearance of this condition with intensity modulated radiation therapy, whereas most cases are managed with electron beam therapy if radiation therapy is implemented

On the Equivalence of Barrier Crossing, Peak-Background Split, and Local Biasing

Several, apparently distinct, formalisms exist in the literature for predicting the clustering of dark matter halos. It has been noticed on a case-by-case basis that the predictions of these different methods agree in specific examples, but there is no general proof that they are equivalent. In this paper, we give a simple proof of the mathematical equivalence of barrier crossing, peak-background split, and local biasing.Comment: 20 pages, 1 figur

Analfabetismo no Brasil: configuração e gênese das desigualdades regionais

O analfabetismo é uma forma extrema de exclusão. O Censo 2000 revela: a persistência do analfabetismo no Brasil, sua distribuição extremamente desigual entre as Unidades da Federação (UFSs) e a configuração regional dessa distribuição. Em 1872 (primeiro Censo), as diferenças entre as províncias eram mínimas. O Censo 1920 evidencia o primeiro rompimento dessa condição de “igualdade” no analfabetismo generalizado. O período 1920/1960 conclui a configuração regional do analfabetismo, assim como aparece no Censo 2000. O que tem empurrado para baixo as taxas de analfabetismo no Brasil é, principalmente, a concentração da administração pública (RJ e DF), a propriedade rural familiar (RS e SC), a urbanização aliada à industrialização (SP e, mais recentemente, MG e PR), a proximidade com os centros do poder político e econômico. Nunca o latifúndio. Nem mesmo o latifúndio do rei café

TeraHz tuning of whispering gallery modes in a PDMS, stand-alone, stretchable microsphere

We report on tuning the optical whispering gallery modes in a poly dimethyl siloxane-based (PDMS) microsphere resonator by more than a THz. The PDMS microsphere system consists of a solid spherical resonator directly formed with double stems on either side. The stems act like tie-rods for simple mechanical stretching of the microresonator over tens of microns, resulting in tuning of the whispering gallery modes by one free spectral range. Further investigations demonstrate that the whispering gallery mode shift has a higher sensitivity (0.13 nm/{\mu}N) to an applied force when the resonator is in its maximally stretched state compared to its relaxed state.Comment: 3 pages, 4 figures, submitted to Optics Letter

Strengths of the resonances at 436, 479, 639, 661, and 1279 keV in the 22^{22}Ne(p,γ\gamma)23^{23}Na reaction

The $^{22}$Ne(p,$\gamma$)$^{23}$Na reaction is included in the neon-sodium cycle of hydrogen burning. A number of narrow resonances in the Gamow window dominates the thermonuclear reaction rate. Several resonance strengths are only poorly known. As a result, the $^{22}$Ne(p,$\gamma$)$^{23}$Na thermonuclear reaction rate is the most uncertain rate of the cycle. Here, a new experimental study of the strengths of the resonances at 436, 479, 639, 661, and 1279 keV proton beam energy is reported. The data have been obtained using a tantalum target implanted with $^{22}$Ne. The strengths $\omega\gamma$ of the resonances at 436, 639, and 661 keV have been determined with a relative approach, using the 479 and 1279 keV resonances for normalization. Subsequently, the ratio of resonance strengths of the 479 and 1279 keV resonances was determined, improving the precision of these two standards. The new data are consistent with, but more precise than, the literature with the exception of the resonance at 661 keV, which is found to be less intense by one order of magnitude. In addition, improved branching ratios have been determined for the gamma decay of the resonances at 436, 479, and 639 keV.Comment: Final version, now using the Kelly et al. (2015) data [15] for normalization; 10 pages, 7 figures, 3 table

Material tipo de la Colección de Herpetología del Museo de La Plata, Buenos Aires, Argentina

El Museo de la Plata (Buenos Aires, República Argentina) se fundó en 1889, y la colección herpetológica comenzó a funcionar poco tiempo después, bajo la responsabilidad de Julio G. Koslowsky. En esta contribución se listan los ejemplares tipo de Anfibios y Reptiles depositados en la colección herpetológica del Museo de La Plata. El material tipo depositado corresponde a 32 especies descriptas desde 1895 hasta la actualidad, incluyendo: 14 holotipos, 115 paratipos, 4 lectotipos, 22 paralectotipos, 1 neotipo y 12 sintipos (sin incluir los ejemplares extraviados). Se proporciona, para cada taxón, la información completa referida a estatus de cada ejemplar tipo, sexo, datos de recolección y modificaciones taxonómicas posteriores.The La Plata Museum (Buenos Aires, República Argentina) was founded on 1889, and after a little time, the herpetological collection started under the responsibility of Julio G. Koslowsky. In this paper the type specimens of Amphibia and Reptilia housed in the collection of the Herpetology Section at the La Plata Museum are listed. These type materials correspond to 32 species described since 1895 until nowadays, and include: 14 holotypes, 115 paratypes, 4 lectotypes, 22 paralectotypes, 1 neotype and 12 sintypes (this list does not include lost specimens). Complete data about taxonomic status, sex, collection data, and subsequent taxonomic changes are given for each taxonAsociación Herpetológica Argentina (AHA