Anisotropic interactions of a single spin and dark-spin spectroscopy in diamond

The nitrogen-vacancy (N-V) center in diamond is a promising atomic-scale system for solid-state quantum information processing. Its spin-dependent photoluminescence has enabled sensitive measurements on single N-V centers, such as: electron spin resonance, Rabi oscillations, single-shot spin readout and two-qubit operations with a nearby 13C nuclear spin. Furthermore, room temperature spin coherence times as long as 58 microseconds have been reported for N-V center ensembles. Here, we have developed an angle-resolved magneto-photoluminescence microscopy apparatus to investigate the anisotropic electron spin interactions of single N-V centers at room temperature. We observe negative peaks in the photoluminescence as a function of both magnetic field magnitude and angle that are explained by coherent spin precession and anisotropic relaxation at spin level anti-crossings. In addition, precise field alignment unmasks the resonant coupling to neighboring dark nitrogen spins that are not otherwise detected by photoluminescence. The latter results demonstrate a means of investigating small numbers of dark spins via a single bright spin under ambient conditions.Comment: 13 pages, 4 figure

Can yield gap analysis be used to inform R & D prioritisation?

The phrase “biggest bang for a buck” is associated with the policy making question that governments and development agencies face: “Where and which crops should receive highest priority for improving local and global food supply?”. A first step of prioritisation is to identify region x crop combinations for which high impact can be anticipated. We developed a new method for this prioritisation exercise and applied it to data from the Global Yield Gap and Water Productivity Atlas (GYGA). Our prioritisation distinguishes between two policy objectives (humanitarian and economic) and builds upon the relative yield gap and climate risk. Results of the prioritisation are presented and visualised in Google Earth

A prosthodontic concept using implants in the resorbed edentulous maxilla

For the treatment of the atrophic edentulous maxilla implant supported overdentures provide the opportunity to obtain proper lip support, speech and cleanliness. A superstructure with high rigidity is needed for an optimal distribution of occlusal loading, to ensure good prognosis for implant survival. A prosthodontic concept using a hybrid construction meets these criteria. It consists of a cast and precision-milled mesostructure fixed to the implants, over which that a removable cast prosthodontic device is placed to which the teeth are attached. It is essential to follow a strict treatment protocol to obtain a good and predictable result.</p

A prosthodontic concept using implants in the resorbed edentulous maxilla

For the treatment of the atrophic edentulous maxilla implant supported overdentures provide the opportunity to obtain proper lip support, speech and cleanliness. A superstructure with high rigidity is needed for an optimal distribution of occlusal loading, to ensure good prognosis for implant survival. A prosthodontic concept using a hybrid construction meets these criteria. It consists of a cast and precision-milled mesostructure fixed to the implants, over which that a removable cast prosthodontic device is placed to which the teeth are attached. It is essential to follow a strict treatment protocol to obtain a good and predictable result.</p

A prosthodontic concept using implants in the resorbed edentulous maxilla

For the treatment of the atrophic edentulous maxilla implant supported overdentures provide the opportunity to obtain proper lip support, speech and cleanliness. A superstructure with high rigidity is needed for an optimal distribution of occlusal loading, to ensure good prognosis for implant survival. A prosthodontic concept using a hybrid construction meets these criteria. It consists of a cast and precision-milled mesostructure fixed to the implants, over which that a removable cast prosthodontic device is placed to which the teeth are attached. It is essential to follow a strict treatment protocol to obtain a good and predictable result.</p

A prosthodontic concept using implants in the resorbed edentulous maxilla

For the treatment of the atrophic edentulous maxilla implant supported overdentures provide the opportunity to obtain proper lip support, speech and cleanliness. A superstructure with high rigidity is needed for an optimal distribution of occlusal loading, to ensure good prognosis for implant survival. A prosthodontic concept using a hybrid construction meets these criteria. It consists of a cast and precision-milled mesostructure fixed to the implants, over which that a removable cast prosthodontic device is placed to which the teeth are attached. It is essential to follow a strict treatment protocol to obtain a good and predictable result.</p

The physics of water and wax in the pores of a working Gas-to-Liquids catalyst

The so-called Fischer-Tropsch catalysis allows to convert natural gas into liquid products and is the underlying mechanism of commercially used "Gas-to-Liquids" plants. The actual reaction takes place in millimetre sized porous pellets in which active metallic particles are dispersed as catalysts. Due to the reaction the pores of the pellets will become filled with the reaction products ("wax" and water), but it is uncertain if the fluid in the pores can be understood as a single liquid phase, a liquid-gas mixture, or multiple continuous phases. The answer to this question is important for a thorough understanding of the transport processes inside the reactor and can be utilized to improve its eciency. In this project, a theoretical analysis of the behaviour inside the pores is performed. It is concluded that a liquid water phase might well exist next to the wax phase. However, the analysis is based on very limited experimental data of unknown quality. Therefore, we propose a number of possible experiments to validate the theoretical concepts

Prosthetic reconstruction after oncological surgery in the head and neck region

The aim of maxillofacial prosthetics is the treatment of patients with head and neck disease in a multidisciplinary way. Intraoral and facial defects are preferably reconstructed by surgical transplantation methods. Patient factors and oncologic factors determine the indication of prosthetic reconstructions. The treatment of patients with an intraoral or facial defect should be based on a close cooperation between maxillofacial prosthetist and MFP technician. The rehabilitation process and the specific role of each are described.</p