| 1. |
- Greenham, Neil, et al.
(författare)
-
Semiconductor nanogaps for the fabrication of molecular electronic devices
- 2001
-
Ingår i: 6th European Conference on Molecular Electronics.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Recent results from the groups of Reed and Heath have shown that it is possible to obtain negative differential resistance and memory effects in molecular electronic devices by depositing electrodes on top of monolayers of organic molecules. For integration with existing technology, however, it is preferable to deposit molecules into nanometre-sized gaps preformed on a substrate. We have developed new methods to produce these gaps without the need to perform lithography at the nanometre scale. The nanometre spacing is defined by the vertical thickness of the oxide layer in a metal-oxide-semiconductor structure, or by the height of an insulating layer in an MBE-grown semiconductor heterostructure. Selective removal of the insulating layer provides a gap into which semiconductor nanocrystals or conjugated molecules may be assembled. We present characterisation of the semiconductor nanogaps, and initial electrical measurements on semiconductor nanocrystals deposited in the gaps.
|
|
| 2. |
- Marto, João Pedro, et al.
(författare)
-
Safety and Outcome of Revascularization Treatment in Patients With Acute Ischemic Stroke and COVID-19: The Global COVID-19 Stroke Registry.
- 2023
-
Ingår i: Neurology. - 1526-632X. ; 100:7
-
Tidskriftsartikel (refereegranskat)abstract
- COVID-19-related inflammation, endothelial dysfunction, and coagulopathy may increase the bleeding risk and lower the efficacy of revascularization treatments in patients with acute ischemic stroke (AIS). We aimed to evaluate the safety and outcomes of revascularization treatments in patients with AIS and COVID-19.This was a retrospective multicenter cohort study of consecutive patients with AIS receiving intravenous thrombolysis (IVT) and/or endovascular treatment (EVT) between March 2020 and June 2021 tested for severe acute respiratory syndrome coronavirus 2 infection. With a doubly robust model combining propensity score weighting and multivariate regression, we studied the association of COVID-19 with intracranial bleeding complications and clinical outcomes. Subgroup analyses were performed according to treatment groups (IVT-only and EVT).Of a total of 15,128 included patients from 105 centers, 853 (5.6%) were diagnosed with COVID-19; of those, 5,848 (38.7%) patients received IVT-only and 9,280 (61.3%) EVT (with or without IVT). Patients with COVID-19 had a higher rate of symptomatic intracerebral hemorrhage (SICH) (adjusted OR 1.53; 95% CI 1.16-2.01), symptomatic subarachnoid hemorrhage (SSAH) (OR 1.80; 95% CI 1.20-2.69), SICH and/or SSAH combined (OR 1.56; 95% CI 1.23-1.99), 24-hour mortality (OR 2.47; 95% CI 1.58-3.86), and 3-month mortality (OR 1.88; 95% CI 1.52-2.33). Patients with COVID-19 also had an unfavorable shift in the distribution of the modified Rankin score at 3 months (OR 1.42; 95% CI 1.26-1.60).Patients with AIS and COVID-19 showed higher rates of intracranial bleeding complications and worse clinical outcomes after revascularization treatments than contemporaneous non-COVID-19 patients receiving treatment. Current available data do not allow direct conclusions to be drawn on the effectiveness of revascularization treatments in patients with COVID-19 or to establish different treatment recommendations in this subgroup of patients with ischemic stroke. Our findings can be taken into consideration for treatment decisions, patient monitoring, and establishing prognosis.The study was registered under ClinicalTrials.gov identifier NCT04895462.
|
|
| 3. |
- Pecunia, Vincenzo, et al.
(författare)
-
Roadmap on energy harvesting materials
- 2023
-
Ingår i: Journal of Physics. - : IOP Publishing. - 2515-7639. ; 6:4
-
Tidskriftsartikel (refereegranskat)abstract
- Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere.
|
|
| 4. |
- Sazio, Pier, et al.
(författare)
-
A silicon structure for electrical characterisation of nanoscale elements
- 2001
-
Ingår i: MRS Spring Meeting 16-20 April 2001. ; 679E, s. B2.3-
-
Konferensbidrag (refereegranskat)abstract
- The problem of mass manufacturing electrode structures suitable for contacting nanoscaleelements lies primarily in the difficulty of fabricating a nanometre-scale gap between twoelectrodes in a well controlled, highly parallel manner. In ULSI circuit production, the gate andsubstrate in MOSFETs are routinely fabricated with a precise vertical spacing of 3 nm betweenthem. In this work, we have investigated a number of highly parallel methods for the generationof nanogaps, including reconfiguration of the ubiquitous MOS device structure. The silicondioxide layer that provides vertical separation and electrical insulation between two regions ofsilicon (the crystalline substrate and the poly-crystalline gate) gives a leakage current of1 nA P-2 at 1 V for an oxide thickness of 2 nm [1]. This will enable objects the size of singlemolecules that are held across this layer to be detected electrically if they provide currents on thenanoampere scale, assuming a parasitic area for leakage between gate and substrate of order1 µm 2 . In the future this kind of device has the potential to provide a bolt-on technology for thefabrication of ULSI circuits in which conventional CMOS devices are directly hybridised withfunctional nanoscale elements.
|
|
