Controlling hole spin dynamics in two‐dimensional hole systems at low temperatures

With the recent discovery of very long hole spin decoherence times in GaAs/AlGaAs heterostructures of more than 70 ns in two-dimensional hole systems, using the hole spin as a viable alternative to electron spins in spintronic applications seems possible. Furthermore, as the hyperfine interaction with the nuclear spins is likely to be the limiting factor for electron spin lifetimes in zero dimensions, holes with their suppressed Fermi contact hyperfine interaction due to their p-like nature should be able to show even longer lifetimes than electrons. For spintronic applications, electric-field control of hole spin dynamics is desirable. Here, we report on time-resolved Kerr rotation and resonant spin amplification measurements on a two-dimensional hole system in a p-doped GaAs/AlGaAs heterostructure. Via a semitransparent gate, we tune the charge density within the sample. We are able to observe a change in the hole g factor, as well as in the hole spin dephasing time at high magnetic fields

Fostering energy awareness in residential homes using mobile devices

There is considerable global effort being made towards identifying ways of reducing energy consumption to cope with growing demands. Although there is potential for energy saving in many sectors, our focus is on reducing energy consumption in residential homes. We have developed a system which combines home automation and energy usage monitoring technologies. The system offers a range of tools designed for mobile devices to assist users with monitoring their energy usage and provides mechanisms for setting up and controlling home appliances to conserve energy. In this paper we describe our system and a user study we have conducted to evaluate its effectiveness. The findings of the study show the potential benefits of this type of mobile technology

USEM: A ubiquitous smart energy management system for residential homes

With the ever-increasing worldwide demand for energy, and the limited available energy resources, there is a growing need to reduce our energy consumption whenever possible. Therefore, over the past few decades a range of technologies have been proposed to assist consumers with reducing their energy use. Most of these have focused on decreasing energy consumption in the industry, transport, and services sectors. In more recent years, however, growing attention has been given to energy use in the residential sector, which accounts for nearly 30% of total energy consumption in the developed countries. Here we present one such system, which aims to assist residential users with monitoring their energy usage and provides mechanisms for setting up and controlling their home appliances to conserve energy. We also describe a user study we have conducted to evaluate the effectiveness of this system in supporting its users with a range of tools and visualizations developed for ubiquitous devices such as mobile phones and tablets. The findings of this study have shown the potential benefits of our system, and have identified areas of improvement that need to be addressed in the future

Resonant spin amplification of hole spin dynamics in two‐dimensional hole systems: experiment and simulation

Spins in semiconductor structures may allow for the realization of scalable quantum bit arrays, an essential component for quantum computation schemes. Specifically, hole spins may be more suited for this purpose than electron spins, due to their strongly reduced interaction with lattice nuclei, which limits spin coherence for electrons in quantum dots. Here, we present resonant spin amplification (RSA) measurements, performed on a p-modulation doped GaAs-based quantum well at temperatures below 500 mK. The RSA traces have a peculiar, butterfly-like shape, which stems from the initialization of a resident hole spin polarization by optical orientation. The combined dynamics of the optically oriented electron and hole spins are well-described by a rate equation model, and by comparison of experiment and model, hole spin dephasing times of more than 70 ns are extracted from the measured data

Assisting Inhabitants of Residential Homes with Management of Their Energy Consumption

Although there are already a range of energy monitoring and automation systems available in the market that target residential homes, mostly with the aim of reducing their total energy consumption, very few of these systems are directly concerned with how those energy savings are actually made. As such, these systems do not provide tools that would allow users to make intelligent decisions about their energy usage strategies, and encourage them to change their energy use behaviour. In this paper we describe a system designed to facilitate planning and control of energy usage activities in residential homes. We also report on a user study of this system which demonstrates its potential for making energy savings possible

Ubiquitin-Dependent Regulation of the Mammalian Hippo Pathway: Therapeutic Implications for Cancer

The Hippo pathway serves as a key barrier for oncogenic transformation. It acts by limiting the activity of the proto-oncogenes YAP and TAZ. Reduced Hippo signaling and elevated YAP/TAZ activities are frequently observed in various types of tumors. Emerging evidence suggests that the ubiquitin system plays an important role in regulating Hippo pathway activity. Deregulation of ubiquitin ligases and of deubiquitinating enzymes has been implicated in increased YAP/TAZ activity in cancer. In this article, we review recent insights into the ubiquitin-mediated regulation of the mammalian Hippo pathway, its deregulation in cancer, and possibilities for targeting the Hippo pathway through the ubiquitin system

Körperverlust und Reinterpretation bei der Aufzeichnung und didaktischen Vermittlung von Negro Spirituals

Negro Spirituals sind zu einem festen Bestandteil von Liederbüchern und Musik-Unterrichtswerken geworden. Obwohl der Höhepunkt der Begeisterung für diese Lieder unter den Jugendlichen längst vorüber ist und sich die Beliebtheit der Spirituals offenbar in Grenzen hält, scheint es doch eine Menge Lehrer zu geben, die auf "ihre" Spirituals auf gar keinen Fall verzichten würden. In der Regel wird der Lehrer heute wohl kaum mehr nach den authentischen Vorbildern seiner Liederbuch-Spirituals fragen, sondern sie mit einigen rhythmischen Zutaten reproduzieren wie andere Folklore auch. Daß im Folklore-Eintopf der Liederbücher und Musik-Unterrichtsswerke viele feinere musikkulturelle Differenzierungen verloren gehen, scheint dem Autor sicher. Weniger sicher ist er, ob die sich vor dem Hintergrund der alles nivellierenden Primitiv-Rhythmik der Hitparadenmusik ereignenden Verluste überhaupt noch registriert werden. Zu den Verlusten bei einer konkreten Gattung und deren Ursachen im musikpädagogischen Bereich gibt diese Arbeit Hinweise. (DIPF/Orig.