Internal transitions of negatively charged magnetoexcitons in quantum dots

We report calculations of oscillator strengths for the far infrared absorption of light by the excitonic complexes Xn- (the excess charge, n, ranging from one to four) confined in quantum dots. The magnetic field is varied in an interval which corresponds to ``filling factors'' between 2 and 3/5. Electron-hole interaction effects are seen in the deviations of the peak positions from the Kohn lines, and in the spreading of the oscillator strengths over a few final states. Transition densities are used as an additional tool to characterize the absorption peaks.Comment: Presented as a poster in the Third Stig Lundqvist Conference on Advancing Frontiers of Condensed Matter Physics: Fundamental Interactions and Excitations in Confined Systems, Trieste, August 11 - 1

If You Can’t Take the Heat: Cultural Beliefs about Questionable Conduct, Stigma, Punishment, and Withdrawal among Mexican Police Officers

We introduce the concept of cultural beliefs about questionable conduct, and examine how these beliefs interact with stigma consciousness to influence punishment and two withdrawal behaviors: turnover and absenteeism. We used a sample of Mexican police officers in a border city and implemented a mixed method design, paying attention to the national, occupational, and organizational context of this setting. We conducted a qualitative phase to explore the prevalence and meaning of occupational stigma and four cultural beliefs about questionable conduct: greed, toughness, wariness, and savvy. The results of this phase helped us develop a context-relevant measure of cultural beliefs about questionable conduct using Mexican proverbs. The results of the quantitative phase indicated that, contingent upon stigma consciousness, beliefs about questionable conduct affected received punishment, turnover, and absenteeism. We discuss the theoretical and behavioral implications of our findings for socialization, identity management, occupational stigma, corruption, and ethical behavior

Towards a Quantum Software Modeling Language

We set down the principles behind a modeling language for quantum software. We present a minimal set of extensions to the well-known Unified Modeling Language (UML) that allows it to effectively model quantum software. These extensions are separate and independent of UML as a whole. As such they can be used to extend any other software modeling language, or as a basis for a completely new language. We argue that these extensions are both necessary and sufficient to model, abstractly, any piece of quantum software. Finally, we provide a small set of examples that showcase the effectiveness of the extension set

Type of grinding of the main cereal of the diet affects production of brown egg-laying hens

The influence of method of grinding of the cereal of the diet on production and egg quality was studied in 420 Hy-line brown egg-laying hens. The design was completely randomized with six treatments arranged as a 3 × 2 factorial with three cereals (barley, dented maize and soft wheat) and two grinding procedures (hammer mill vs. roller mill). Each treatment was replicated seven times and the experimental unit was an enriched cage with ten hens. Production was recorded every four weeks from 24 to 59 weeks of age and egg quality was measured at 40 and 56 weeks of age. For the entire experiment, feed intake was higher in hens fed wheat or maize than in hens fed barley (110.8 and 110.7 vs. 109.7 g/d; P = 0.014) but most of the differences were observed when the cereal was roller milled (P = 0.009 for the interaction). Also, egg production was similar for the three diets when the cereal was hammer milled but tended to be lower for the barley than for the wheat or maize diets when the cereal was roller milled (P = 0.09 for the interaction). None of the other productive or egg quality traits was affected by dietary treatment. We conclude that roller mills are useful to grind low fiber cereals, such as maize or wheat. However, the use of the roller mill might not be adequate when barley is the main cereal in diets for egg-laying hens

Evaluación de un intercambiador de calor de placas para el enfriamiento de ácido acético

In today heat exchange applications, the plate heat exchanger (PHE) is quite used in chemical en food industries. At the present work the assessment of a PHE to carry out the cooling of an acetic acid stream, using ethylene glycol as refrigerant agent was accomplished. It was obtained a value of 29.34 % for the percent over surface design (OS), a heat exchanger effectiveness (ε) value of 0.667, a number of heat transfer units (NTU) value of 1.316, while the pressure drop results for both the acetic acid (6.70 kPa) and ethylene glycol (82.06 kPa) were below the maximum permissible limit for the process (100 kPa). The increment of the acetic acid feed flowrate increased the values of the three parameters considered, while the increment of the acetic acid inlet temperature augmented three of the variables taken into account, except for the acetic acid pressure drop, which was reduced. The proposed PHE can be satisfactorily used for the evaluated heat transfer process.En las aplicaciones de intercambio de calor actuales, el intercambiador de calor de placas (ICP) es muy empleado en las industrias químicas y la alimenticia. En el presente trabajo se efectuó la evaluación de un ICP para llevar a cabo el enfriamiento de una corriente de ácido acético, utilizando etilenglicol como agente refrigerante. Se obtuvo un valor del porcentaje de sobrediseño de superficie (PSS) de 29,34 %, una efectividad de transferencia de calor (ε) de 0,667, un número de unidades de transferencia (NUT) de 1,316, mientras que las caídas de presión de tanto el ácido acético (6,70 kPa) como el etilenglicol (82,06 kPa) se encontraron por debajo del límite máximo permisible por el proceso (100 kPa). El incremento del caudal de alimentación del ácido acético aumentó los valores de los tres parámetros considerados, mientras que el incremento de la temperatura de entrada del ácido acético aumentó tres de las variables tomadas en cuenta, con excepción de la caída de presión del ácido acético, que se redujo. El ICP propuesto puede ser empleado satisfactoriamente para el proceso de transferencia de calor evaluado

Evaluación de un intercambiador de calor de placas para el enfriamiento de ácido acético

En las aplicaciones de intercambio de calor actuales, el intercambiador de calor de placas (ICP) es muy empleado en las industrias químicas y la alimenticia. En el presente trabajo se efectuó la evaluación de un ICP para llevar a cabo el enfriamiento de una corriente de ácido acético, utilizando etilenglicol como agente refrigerante. Se obtuvo un valor del porcentaje de sobrediseño de superficie (PSS) de 29,34 %, una efectividad de transferencia de calor (ε) de 0,667, un número de unidades de transferencia (NUT) de 1,316, mientras que las caídas de presión de tanto el ácido acético (6,70 kPa) como el etilenglicol (82,06 kPa) se encontraron por debajo del límite máximo permisible por el proceso (100 kPa). El incremento del caudal de alimentación del ácido acético aumentó los valores de los tres parámetros considerados, mientras que el incremento de la temperatura de entrada del ácido acético aumentó tres de las variables tomadas en cuenta, con excepción de la caída de presión del ácido acético, que se redujo. El ICP propuesto puede ser empleado satisfactoriamente para el proceso de transferencia de calor evaluado

Lepton Number Violation from Colored States at the LHC

The possibility to search for lepton number violating signals at the Large Hadron Collider (LHC) in the colored seesaw scenario is investigated. In this context the fields that generate neutrino masses at the one-loop level are scalar and Majorana fermionic color-octets of SU(3). Due to the QCD strong interaction these states may be produced at the LHC with a favorable rate. We study the production mechanisms and decays relevant to search for lepton number violation signals in the channels with same-sign dileptons. In the simplest case when the two fermionic color-octets are degenerate in mass, one could use their decays to distinguish between the neutrino spectra. We find that for fermionic octets with mass up to about 1 TeV the number of same-sign dilepton events is larger than the standard model background indicating a promising signal for new physics.Comment: minor corrections, added reference

Response of alluvial systems to Late Pleistocene climate changes recorded by environmental magnetism in the Añavieja Basin (Iberian Range, NE Spain)

Environmental magnetic proxies were analyzed in a relatively monotonous, ~25.3m thick alluvial sedimentary sequence drilled in the Añavieja Basin (NE Spain). Results from the core AÑ2 suggest that the concentrationdependent magnetic parameters mainly reflect variations in the content of detrital magnetite, sourced in the catchment rocks and soils of the basin, via changes in the dynamics of alluvial fans due to temperature changes in the northern hemisphere during the Late Pleistocene. The correspondence between the magnetic proxies and the temperature variations in the North Atlantic region (NGRIP curve) indicates that higher (lower) concentrations and finer (coarser) magnetite grains coincide with warm (cold) periods. We propose that during cold periods, a sparser vegetation cover favored the incoming of higher energy runoff bearing coarser sediments to the basin that are relatively impoverished in magnetite. In contrast, during warm periods, the wider distribution of the vegetation cover associated with the lower runoff energy lead to finer, magnetite-richer sediment input to the basin. Maghemite, presumably of pedogenic origin, appears to be present also in the studied alluvial sediments. Further studies are necessary to unravel its palaeoclimatic significance