309 research outputs found
Balanced ternary addition using a gated silicon nanowire
We demonstrate the proof of principle for a ternary adder using silicon
metal-on-insulator single electron transistors (SET). Gate dependent rectifying
behavior of a single electron transistor results in a robust three-valued
output as a function of the potential of the SET island. Mapping logical,
ternary inputs to the three gates controlling the potential of the SET island
allows us to perform complex, inherently ternary operations, on a single
transistor
Discussies in de klas ten tijde van maatschappelijke onrust. Een onderzoek naar de betekenis van polarisatie voor het voeren van klassendiscussies over controversiële issues
In deze scriptie staat de vraag naar de betekenis van culturele en levensbeschouwelijke polarisatie op het kunnen voeren van klassikale discussies over controversiële issues centraal, waarbij de Nederlandse context het uitgangspunt vormt. Aanleiding voor deze scriptie is de oproep van het Ministerie van Onderwijs, Cultuur en Wetenschap om in het kader van burgerschapsvorming controversiële issues te bespreken in de klas en de signalen vanuit het onderwijs dat het voeren van dergelijke discussies ernstig wordt bemoeilijkt door polarisatie. Deze scriptie start met een verkenning van de huidige context waarin culturele en levensbeschouwelijke polarisatie in Nederland plaatsvindt en met behulp van sociaal wetenschappelijke literatuur is in beeld gebracht uit welke centrale kenmerken deze culturele en levensbeschouwelijke polarisatie bestaat. Vervolgens is aan de hand van literatuur over burgerschapsvorming een drietal condities besproken met haar onderliggende elementen die aan de basis liggen voor het kunnen voeren van een goede klassikale discussie over controversiële issues. Door deze resultaten te verbinden met de centrale kenmerken van culturele en levensbeschouwelijke polarisatie wordt geconcludeerd dat de huidige polarisatie vooral de bereidheid raakt van de leerlingen en de docent. Het gaat hierbij om de bereidheid van de Turks- en Marokkaans- Nederlandse moslimleerlingen en de autochtone Nederlandse leerlingen om in de discussie naar elkaar te willen luisteren, maar ook de bereidheid van de docent om positie in te nemen naast leerlingen die er andere waardeoriëntaties op na houden dan hem
Magnetic Field Probing of an SU(4) Kondo Resonance in a Single Atom Transistor
Semiconductor nano-devices have been scaled to the level that transport can
be dominated by a single dopant atom. In the strong coupling case a Kondo
effect is observed when one electron is bound to the atom. Here, we report on
the spin as well as orbital Kondo ground state. We experimentally as well than
theoretically show how we can tune a symmetry transition from a SU(4) ground
state, a many body state that forms a spin as well as orbital singlet by
virtual exchange with the leads, to a pure SU(2) orbital ground state, as a
function of magnetic field. The small size and the s-like orbital symmetry of
the ground state of the dopant, make it a model system in which the magnetic
field only couples to the spin degree of freedom and allows for observation of
this SU(4) to SU(2) transition.Comment: 12 pages, 10 figures, accepted for publication in Physical Review
Letter
Heterointerface effects on the charging energy of shallow D- ground state in silicon: the role of dielectric mismatch
Donor states in Si nanodevices can be strongly modified by nearby insulating
barriers and metallic gates. We report here experimental results indicating a
strong reduction in the charging energy of isolated As dopants in Si FinFETs
relative to the bulk value. By studying the problem of two electrons bound to a
shallow donor within the effective mass approach, we find that the measured
small charging energy may be due to a combined effect of the insulator
screening and the proximity of metallic gates.Comment: 7 pages, 6 figure
A hybrid double-dot in silicon
We report electrical measurements of a single arsenic dopant atom in the
tunnel-barrier of a silicon SET. As well as performing electrical
characterization of the individual dopant, we study series electrical transport
through the dopant and SET. We measure the triple points of this hybrid double
dot, using simulations to support our results, and show that we can tune the
electrostatic coupling between the two sub-systems.Comment: 11 pages, 6 figure
Development of a local dose-response relationship for osteoradionecrosis within the mandible
Purpose: Osteoradionecrosis (ORN) of the mandible is a severe complication following radiotherapy of the head and neck, but not all regions of the mandible may be equally at risk. Therefore our goal was to explore a local dose response relationship for subregions of the mandible. Materials and methods: All oropharyngeal cancer patients treated at our hospital between 2009 and 2016 were reviewed. Follow-up was cut-off at 3 years. For patients that developed ORN, the ORN volume was delineated on the planning CT. Each mandible was divided into 16 volumes of interest (VOIs) based on the location of the dental elements and the presence of ORN in each was scored. Generalized estimating equations were used to build a model for the probability of developing ORN in an element VOI. Results: Of the 219 included patients, 22 developed ORN in 89 element VOIs. Mean dose to the element VOI (odds ratio (OR) = 1.05 per Gy, 95% confidence interval (CI): (1.04,1.07)), pre-radiotherapy extractions of an element ipsilateral to element of interest (OR = 2.81, 95% CI: (1.12,7.05)), and smoking at start of radiotherapy (OR = 3.37, 95% CI: (1.29,8.78)) were significantly associated with an increased probability of ORN in the VOI. Conclusion: The developed dose-response model indicates that the probability of ORN varies within the mandible and strongly depends on the local dose, the location of extractions, and smoking.</p
Personalizing dental screening and prevention protocols in dentulous patients with oropharyngeal cancer undergoing radiotherapy:A retrospective cohort study
Objectives:Patients with head and neck cancer are routinely screened for dental foci prior to radiotherapy (RT) to prevent post- RT tooth extractions associated with an increased risk of osteoradionecrosis. We evaluated the risk factors for post-RT tooth extraction to personalise dental screening and prevention protocols prior to RT. Materials and methods: This retrospective cohort study included dentulous patients diagnosed with oropharyngeal cancer who had undergone radiation therapy at doses 60–70 Gy and achieved a disease-free survival of ≥ 1 year (N = 174). Risk factors were assessed using Cox regression models. Results: The cumulative incidence of post-RT tooth extraction was 30.7 % at 5 years. Main indications for extraction (n = 62) were radiation caries (n = 20) and periodontal disease (n = 27). Risk factors associated (p < 0.05) with radiation caries-related extractions included active smoking, alcohol abuse, poor oral hygiene, parotid gland irradiation, and mandibular irradiation. A high-dose volume in the mandible was associated with periodontal disease events. Conclusion: Post-RT extractions due to radiation caries were influenced by lifestyle factors and RT dose in the mandible and parotid glands. Periodontal disease-related extractions were primarily associated with the mandibular dose. During dental screening these post-RT risk factors should be taken into account to prevent osteoradionecrosis.</p
Mass Production of Silicon MOS-SETs: Can We Live with Nano-Devices’ Variability?
AbstractIt is very important to study variability of nanodevices because the inability to produce large amounts of identical nanostructures is eventually a bottleneck for any application. In fact variability is already a major concern for CMOS circuits. In this work we report on the variability of dozens of silicon single-electron transistors (SETs). At room temperature their variability is compared with the variability of the most advanced CMOS FET i.e. the ultra thin Silicon-on-Insulator Multiple gate FET (UT SOI MuGFET). We found that dopants diffused from Source –Drain into the edge of the undoped channel are the main source of variability. This emphasizes the role of extrinsic factors like the contact junctions for variability of any nanodevice
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