230 research outputs found
Dust in high-z radio-loud AGN
We present continuum observations of a small sample of high-redshift,
radio-loud AGN (radio galaxies and quasars) aimed at the detection of thermal
emission from dust. Seven AGN were observed with IRAM and SEST at 1.25mm; two
of them, the radio galaxies 1243+036 () and MG1019+0535 () were also observed at 0.8mm with the JCMT submillimetre telescope.
Additional VLA observations were obtained in order to derive the spectral shape
of the synchrotron radiation of MG1019+0535 at high radio frequencies.
MG1019+0535 and TX0211122 were expected to contain a large amount of dust
based on their depleted Ly emission. The observations suggest a clear
1.25-mm flux density excess over the synchrotron radiation spectrum of
MG1019+0535, suggesting the presence of thermal emission from dust in this
radio galaxy, whereas the observations of TX0211122 were not sensitive
enough to meaningfully constrain its dust content. On the other hand, our
observations of 1243+036 provide a stringent upper limit on the total dust mass
of M. Finally, we find that the spectra of the radio-loud
quasars in our sample () steepen between rest-frame radio and the
far-infrared. We discuss the main implications of our results, concentrating on
the dusty radio galaxy, MG1019+0535.Comment: 11 pages, A&A LaTeX, 4 figure
Pauli Tomography: complete characterization of a single qubit device
The marriage of Quantum Physics and Information Technology, originally
motivated by the need for miniaturization, has recently opened the way to the
realization of radically new information-processing devices, with the
possibility of guaranteed secure cryptographic communications, and tremendous
speedups of some complex computational tasks. Among the many problems posed by
the new information technology there is the need of characterizing the new
quantum devices, making a complete identification and characterization of their
functioning. As we will see, quantum mechanics provides us with a powerful tool
to achieve the task easily and efficiently: this tools is the so called quantum
entanglement, the basis of the quantum parallelism of the future computers. We
present here the first full experimental quantum characterization of a
single-qubit device. The new method, we may refer to as ''quantum
radiography'', uses a Pauli Quantum Tomography at the output of the device, and
needs only a single entangled state at the input, which works on the test
channel as all possible input states in quantum parallel. The method can be
easily extended to any n-qubits device
Overview of the EVALITA 2016 Part of speech on twitter for Italian task
The increasing interest for the extraction of various forms of knowledge from micro-blogs and social media makes crucial the development of resources and tools that can be used for automatically deal with them. PoSTWITA contributes to the advancement of the state-of-the-art for Italian language by: (a) enriching the community with a previously not existing col- lection of data extracted from Twitter and annotated with grammatical categories, to be used as a benchmark for system evaluation; (b) supporting the adaptation of Part of Speech tagging systems to this particular text domain
Exploiting quantum parallelism of entanglement for a complete experimental quantum characterization of a single qubit device
We present the first full experimental quantum tomographic characterization
of a single-qubit device achieved with a single entangled input state. The
entangled input state plays the role of all possible input states in quantum
parallel on the tested device. The method can be trivially extended to any
n-qubits device by just replicating the whole experimental setup n times.Comment: 4 pages in revtex4 with 4 eps figure
Nanoparticles modified screen printed electrode for electrochemical determination of COD
The Chemical Oxygen Demand (COD) is a parameter widely used to determine organic pollutants in water and is defined as the number of oxygen equivalents necessary to oxidize the organic compounds. The standard method for COD measurement (the dichromate titration) suffers from several inherent drawbacks such as the long time of the process and the consumption of toxic chemicals. Hence, interest is growing towards those methods employing electrochemical oxidation of organic compounds, as they allow to dispense with toxic reagents and above all to perform a continuous determination.
In this work a new electrochemical method for COD measurement has been developed based on direct oxidation of organic molecules on suitably modified electrodic surfaces.
In particular, we have developed various sensors based on modified working electrode surfaces obtained by electrodepositing copper and/or nickel oxide nanoparticles onto several commercial screen printed electrodes. Glucose was used as the standard compound for COD measurements: C6H12O6 + 6O2 → 6CO2 + 6H2O
The metallic nanoparticles catalyze the oxidation of the glucose, as well as of different organic pollutants, and make the detection possible at relatively low potential, also in presence of chloride as interferent. The analytical parameters were optimized and the results obtained highlight how the electrodeposition of different metallic nanoparticles onto several screen printed electrode surfaces can influence the selectivity and sensitivity towards the COD detection in real matrices, via electrochemical method. The results were compared with those obtained by the standard method and showed a good agreement. These findings provide an interesting strategy to obtain a simple, cheap, portable and eventually continuous sensor for COD measurement
When alarm bells ring: emergency tinnitus
OBJECTIVE: The aim of this study is to develop a diagnostic-therapeutic algorithm for those suffering from tinnitus who seek emergency aid.
MATERIALS AND METHODS: A literature review has been performed on articles from the last 30 years.
RESULTS: It is important to activate medical or surgical diagnostic and therapeutic strategies, in order to safeguard and rehabilitate the various functions affected. Psychiatric comorbidity is the most frequent pathological condition of those with serious or catastrophic tinnitus. In these cases, mortality risk is linked to suicide, morbidity to tinnitus-correlated distress.
CONCLUSIONS: Tinnitus, mainly linked to loss of hearing, is a frequent symptom among the population at large. About 7% of those affected by tinnitus turn to their doctor to solve their problem, while between 0.5 and 2% request urgent medical assistance. Their cry for help may be the result of an acute onset of tinnitus or the rapid impairment of an already chronic condition. Tinnitus is not considered an urgent ear, nose and throat (ENT) condition by the Associazione Otorinolaringologi Ospedalieri Italiani
(AOOI) [Italian Association of Hospital ENT], even though there are many pathological conditions,
sometimes serious, associated with tinnitus and emergency action is necessary to reduce the risk of morbidity and mortality
Extraction and Classification of Handwritten Annotations
This article describes a method for extracting and classifying handwritten annotations on printed documents using a simple camera integrated in a lamp or a mobile phone. The ambition of such a research is to offer a seamless integration of notes taken on printed paper in our daily interactions with digital documents. Existing studies propose a classification of annotations based on their form and function. We demonstrate a method for automating such a classification and report experimental results showing the classification accuracy
Cognitive and social effects of handwritten annotations
This article first describes a method for extracting and classifying handwritten annotations on printed documents using a simple camera integrated in a lamp. The ambition of such a research is to offer a seamless integration of notes taken on printed paper in our daily interactions with digital documents. Existing studies propose a classification of annotations based on their form and function. We demonstrate a method for automating such a classification and report experimental results showing the classification accuracy. In the second part of the article we provide a road map for conducting user-centered studies using eye-tracking systems aiming to investigate the cognitive roles and social effects of annotations. Based on our understanding of some research questions arising from this experiment, in the last part of the article we describe a social learning environment that facilitates knowledge sharing across a class of students or a group of colleagues through shared annotations
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