Die weisheit d. Martin Luther's ...

1. t. Auslegung des Magnificat.-Psalm 37, 62, 82, 117, 111, 127, 147, 118. Jeremia kap. 23. Esaja kap. 9. Habakuk kap. 1, 3. Die zehn gebote. Die bergpredigt. Evangel. Joh. kap. 14-16. Das Vaterunser.--2. t. Auslegung des ersten buches Mose. Auslegung des ersten briefes Petri, sammt dem ersten kapitel des andern briefes. Auslegung des fünfzehnten kapitels des ersten briefes Pauli an die Corinther.

Nonlinear Optics and Carrier Dynamics in Nanostructured and Two-Dimensional Materials

Understanding and measuring the interaction of light with sub-wavelength structures and atomically thin materials is of critical importance for the development of next generation photonic devices.  One approach to achieve the desired optical properties in a material is to manipulate its mesoscopic structure or its composition in order to affect the properties of the light-matter interaction.  There has been tremendous recent interest in so called two-dimensional materials, consisting of only a single to a few layers of atoms arranged in a planar sheet.  These materials have demonstrated great promise as a platform for studying unique phenomena arising from the low-dimensionality of the material and for developing new types of devices based on these effects.  A thorough investigation of the optical and electronic properties of these new materials is essential to realizing their potential.  In this work we present studies that explore the nonlinear optical properties and carrier dynamics in nanoporous silicon waveguides, two-dimensional graphite (graphene), and atomically thin black phosphorus. We first present an investigation of the nonlinear response of nanoporous silicon optical waveguides using a novel pump-probe method. A two-frequency heterodyne technique is developed in order to measure the pump-induced transient change in phase and intensity in a single measurement. The experimental data reveal a characteristic material response time and temporally resolved intensity and phase behavior matching a physical model dominated by free-carrier effects that are significantly stronger and faster than those observed in traditional silicon-based waveguides.  These results shed light on the large optical nonlinearity observed in nanoporous silicon and demonstrate a new measurement technique for heterodyne pump-probe spectroscopy. Next we explore the optical properties of low-doped graphene in the terahertz spectral regime, where both intraband and interband effects play a significant role. Probing the graphene at intermediate photon energies enables the investigation of the nonlinear optical properties in the graphene as its electron system is heated by the intense pump pulse. By simultaneously measuring the reflected and transmitted terahertz light, a precise determination of the pump-induced change in absorption can be made. We observe that as the intensity of the terahertz radiation is increased, the optical properties of the graphene change from interband, semiconductor-like absorption, to a more metallic behavior with increased intraband processes. This transition reveals itself in our measurements as an increase in the terahertz transmission through the graphene at low fluence, followed by a decrease in transmission and the onset of a large, photo-induced reflection as fluence is increased.  A hybrid optical-thermodynamic model successfully describes our observations and predicts this transition will persist across mid- and far-infrared frequencies.  This study further demonstrates the important role that reflection plays since the absorption saturation intensity (an important figure of merit for graphene-based saturable absorbers) can be underestimated if only the transmitted light is considered. These findings are expected to contribute to the development of new optoelectronic devices designed to operate in the mid- and far-infrared frequency range.  Lastly we discuss recent work with black phosphorus, a two-dimensional material that has recently attracted interest due to its high mobility and direct, configurable band gap (300 meV to 2eV), depending on the number of atomic layers comprising the sample. In this work we examine the pump-induced change in optical transmission of mechanically exfoliated black phosphorus flakes using a two-color optical pump-probe measurement. The time-resolved data reveal a fast pump-induced transparency accompanied by a slower absorption that we attribute to Pauli blocking and free-carrier absorption, respectively. Polarization studies show that these effects are also highly anisotropic - underscoring the importance of crystal orientation in the design of optical devices based on this material. We conclude our discussion of black phosphorus with a study that employs this material as the active element in a photoconductive detector capable of gigahertz class detection at room temperature for mid-infrared frequencies.

Optimization of quantum states for signaling across an arbitrary qubit noise channel with minimum-error detection

International audience

Gender theory and the family business

Gender Theory started in understanding and explain women's role in society and are also now including men and masculinities, Gender Theory has recently been adapted to family business research. This chapter will briefly introduce Gender Theory and its development, before reviewing how it has been used in family business research. Arguing that the family business context is suitable in studying gender phenomena, the chapter outlines several ways through which Gender Theory could yield new insights into issues, of how family business structures, settings and practices produce relations of power or asymmetry. A common approach so far to the study of gender in family business situations is to consider ‘gender as a variable’, which maintains the categorisation of women and men as a relevant and unproblematic variable. Many analyses of family businesses that also address gender focus on feminist ‘standpoint positions’, giving voice to women´s unique experiences. Often in family business research, the dominant approach is to conceive gender in terms of limited male/female distinctions rather than by reframing family business through critical positions, with the aim of reflection and sensitivity towards gender issues in terms of the socially constituted patterns that are produced through male/female, masculine/feminine distinctions. Concluding, the chapter suggests a possible methodology for capturing gendered processes and proposes how family business research could offer new insights into Gender theory.

Detectability of migrating raptors and its effect on bias and precision of trend estimates

Annual counts of migrating raptors at fixed observation points are a widespread practice, and changes in numbers counted over time, adjusted for survey effort, are commonly used as indices of trends in population size. Unmodeled year-to-year variation in detectability may introduce bias, reduce precision of trend estimates, and reduce power to detect trends. We conducted dependent double-observer surveys at the annual fall raptor migration count at Lucky Peak, Idaho, in 2009 and 2010 and applied Huggins closed-capture removal models and information-theoretic model selection to determine the relative importance of factors affecting detectability. The most parsimonious model included effects of observer team identity, distance, species, and day of the season. We then simulated 30 years of counts with heterogeneous individual detectability, a population decline (λ = 0.964), and unexplained random variation in the number of available birds. Imperfect detectability did not bias trend estimation, and increased the time required to achieve 80% power by less than 11%. Results suggested that availability is a greater source of variance in annual counts than detectability; thus, efforts to account for availability would improve the monitoring value of migration counts. According to our models, long-term trends in observer efficiency or migratory flight distance may introduce substantial bias to trend estimates. Estimating detectability with a novel count protocol like our double-observer method is just one potential means of controlling such effects. The traditional approach of modeling the effects of covariates and adjusting the index may also be effective if ancillary data is collected consistently.

Impacto de la biología en los modelos de gestión y control organizacional

Desde el inicio de las organizaciones han existido modelos de control rígidos como los sistemas mecanicistas y formales en donde la perspectiva racional sobresale y no se tienen en cuenta los aspectos humanos en el diseño de los sistemas. Estos modelos de control rígidos, estandarizados y centralizados suponen un problema para el adecuado desarrollo estratégico y operativo de las organizaciones. Sin embargo, desde los sistemas biológicos se pueden observar aportes de autores que destacan la ausencia de control y su consecuente funcionamiento armónico a través de propiedades como la auto-organización y la emergencia. De esta forma, este artículo de revisión tiene como objetivo identificar las aproximaciones teóricas que se han realizado en torno a los principales aportes que los modelos biológicos han hecho a la gestión administrativa y específicamente al control organizacional mediante el análisis de la producción bibliográfica realizada en los últimos 10 años.

Equazioni di stato della materia in astrofisica

Le equazioni di stato (EdS) sono relazioni che permettono di descrivere sistemi termodinamici all'equilibrio. Un esempio di questi sistemi sono i gas, che si possono dividere in gas perfetti e gas degeneri, che differiscono per importanti proprietà e caratteristiche fisiche. Le proprietà dei gas degeneri cambiano in base al tipo di particelle che li compongono, il comportamento di un gas degenere di Fermioni è molto diverso da quello di un gas degenere di Bosoni. Per lo studio e la descrizione dei gas degeneri di Fermioni entrano in gioco il principio di esclusione di Pauli ed il principio di inderteminazione di Heisenberg. Attraverso le EdS si possono descrivere gli interni stellari poiché per via delle alte temperature le stelle sono formate da gas completamente ionizzato. La pressione all'interno di una stella è data dalla somma tra la pressione di radiazione, la pressione elettronica e la pressione ionica, in base al tipo di gas elettronico che si ha ed alla temperatura interna la stella può essere formata da gas perfetto o gas degenere. Lo studio del regime di pressione interno per una stella si fa con il grafico densità-temperatura, in cui una stella viene rappresentata nel piano attraverso queste due grandezze. Si vede come le stelle di sequenza principale siano formate da gas perfetto mentre i corpi compatti come le nane bianche sono formati da gas completamente degenere. Attraverso le EdS ed il principio dell'equilibrio idrostatico si possono ricavare la temperatura interna per le stelle di sequenza principale e la relazione massa-raggio per le nane bianche.