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Quantum wells within quantum dots, a CdS/HgS nanoheterostructure with global and local confinement
1998
Semiconductor nanocrystals prepared by methods of wet chemistry are similar to MBE grown quantum dots where the mobility of the charge carriers is reduced to zero dimensionality. In this paper we summarize the physics of a unique system in which the charge carriers are locally confined within a heterogeneous quantum dot. With high resolution electron microscopy we will show that epitaxial growth ot atomic layer precision is possible by methods of solution chemistry leading to CdS quantum dots with embedded HgS quantum wells (QDQWs). The photophysics of this system is investigated by time-correlated single photon counting, transient differential absorption and fluorescence line narrowing spe…
Co-adsorption processes, kinetics and quantum mechanical modelling of nanofilm semiconductor gas sensors
2010
A quantum mechanical model of co-adsorption on semiconductor surfaces is developed and successfully adopted towards exposure to several gases. It is related to nanofilms and thus allows the application of electric fields altering the electronic surface properties of adsorption centres (electro-adsorptive effect, EAE). The model is matched against experimental data with O 2 , NO 2 and CO measurements under the hypothesis of no direct interaction among the species. However the sequence of adsorption plays an important role where the adsorption of one gas species is opening up other sites that are filled by another sort of impinging molecules. Quantum mechanical modelling of co-adsorption: (a)…
Interligand Electron Transfer Determines Triplet Excited State Electron Injection in RuN3−Sensitized TiO2 Films
2004
Electron injection from the transition metal complex Ru(dcbpy)(2)(NCS)(2) (dcbpy = 2,2'-bipyridine-4,4'-dicarboxylate) into a titanium dioxide nanoparticle film occurs along two pathways. The dominating part of the electron injection proceeds from the initially excited singlet state of the sensitizer into the conduction band of the semiconductor on the sub-hundred-femtosecond time scale. The slower part of the injection occurs from the thermalized triplet excited state on the picosecond time scale in a nonexponential fashion, as was shown in a previous study (Benko, G.; et al. J. Am. Chem. Soc. 2002, 124, 489). Here we show that the slower channel of injection is the result of the excited s…
Design and development of a fNIRS system prototype based on SiPM detectors
2014
Functional Near Infrared Spectroscopy (fNIRS) uses near infrared sources and detectors to measure changes in absorption due to neurovascular dynamics in response to brain activation. The use of Silicon Photomultipliers (SiPMs) in a fNIRS system has been estimated potentially able to increase the spatial resolution. Dedicated SiPM sensors have been designed and fabricated by using an optimized process. Electrical and optical characterizations are presented. The design and implementation of a portable fNIRS embedded system, hosting up to 64 IR-LED sources and 128 SiPM sensors, has been carried out. The system has been based on a scalable architecture whose elementary leaf is a flexible board …
New Areas of Application of Comparable Corpora
2019
This chapter describes several approaches of using comparable corpora beyond the area of MT for under-resourced languages, which is the primary focus of the ACCURAT project. Section 7.1, which is based on Rapp and Zock (Automatic dictionary expansion using non-parallel corpora. In: A. Fink, B. Lausen, W. Seidel, & A. Ultsch (Eds.) Advances in Data Analysis, Data Handling and Business Intelligence. Proceedings of the 32nd Annual Meeting of the GfKl, 2008. Springer, Heidelberg, 2010), addresses the task of creating resources for bilingual dictionaries using a seed lexicon; Sect. 7.2 (based on Rapp et al., Identifying word translations from comparable documents without a seed lexicon. Proceedi…
The Importance of Multilingual Information and Plain English in Response to the COVID-19 Pandemic
2021
Health is a common issue for all human beings. As a consequence, everyone in the world has in some way to cope with the language of medicine. This is true now more than ever due to the global health crisis caused by the current COVID-19 pandemic, which has introduced a great amount of terms, previously mostly used by epidemiologists and statisticians, but which now have entered the daily lexicon of many languages. As the medium of international scientific communication, English is the language of worldwide information about the pandemic, and the main source of terms and expressions for other languages. The impact of the COVID-19 pandemic on English lexicon has been so deep that the Oxford E…
No evidence for efficacy of intrathecal verapamil in the treatment of tonic-clonic status epilepticus
1992
In two patients with refractory generalized tonic-clonic status epilepticus, 15 mg of the calcium antagonist verapamil was given by suboccipital intrathecal administration. During a 2–6-h observation period, seizure frequency did not decrease. However, in one patient, verapamil induced severe hypotension. Subsequent thiopental anesthesia suppressed convulsions immediately. Our results indicate that, in contradistinction to animal studies with different administration techniques, intrathecal administration of verapamil does not produce any anticonvulsant effect in humans.
Ketogenic diet as a metabolic therapy for mood disorders: Evidence and developments.
2018
Abstract Despite significant advances in pharmacological and non-pharmacological treatments, mood disorders remain a significant source of mental capital loss, with high rates of treatment resistance, requiring a coordinated effort in investigation and development of efficient, tolerable and accessible novel interventions. Ketogenic diet (KD) is a low-carb diet that substantially changes the energetic matrix of the body including the brain. It has been established as an effective anticonvulsant treatment, and more recently, the role of KD for mental disorders has been explored. Ketogenic diet has profound effects in multiple targets implicated in the pathophysiology of mood disorders, inclu…
Physically-consistent parameterization in the modeling of solar photovoltaic devices
2011
This research tests the standard one-diode model of a crystalline-Si photovoltaic cell, focusing on the physical accuracy. In particular, the (apparent) shunt resistance and the diode ideality factor are studied. Current-voltage characteristics of illuminated crystalline-Si photovoltaic modules are analyzed, and some limits of applicability of the standard model are given. Typical values of the ideality factor for crystalline-Si devices are derived from own experimental data as well as from recently published literature. It is shown that the contribution of the apparent shunt resistance is only significant for cell voltages below about 0.45 V, and depends on irradiance. This result is consi…
El léxico coloquial argentino en los “sketches” humorísticos
2017
En la lengua española encontramos una gran riqueza dialectológica y es, precisamente, esa variedad la que explica la existencia de identidades lingüísticas en cada una de las comunidades hispanas. Mediante el léxico coloquial, podemos observar uno de los ámbitos más diferenciales y, por lo tanto, identitarios en cada una de esas comunidades; de hecho, para este artículo se propone analizar, concretamente, el léxico coloquial argentino. Siguiendo esta búsqueda lingüística de lo propio, se ha trabajado sobre un contexto donde el registro sea actual, popular y coloquial, como es el caso del ámbito humorístico. De esta manera, nos proponemos en este trabajo encontrar aquellas voces propias del …