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41.
Marco Lucamarini Alessandro Ceré Giovanni Di Giuseppe Stefano Mancini David Vitali Paolo Tombesi 《Open Systems & Information Dynamics》2007,14(2):169-178
The security of a deterministic quantum scheme for communication, namely the LM05 [1], is studied in presence of a lossy channel
under the assumption of imperfect generation and detection of single photons. It is shown that the scheme allows for a rate
of distillable secure bits higher than that pertaining to BB84 [2]. We report on a first implementation of LM05 with weak
pulses. 相似文献
42.
Marco A. Arteaga Author Vitae 《Automatica》2003,39(1):67-73
Most adaptive control schemes for rigid robots assume velocities measurements to be available. Although it is possible to measure velocities by using tachometers, this increases costs and the signals delivered may be contaminated with noise. Since the use of encoders allows to read joint position pretty accurately, it is desirable to estimate joint velocities through an observer. This paper presents an adaptive scheme designed in conjunction with a linear observer. Boundedness of the estimated parameters and uniform ultimate boundedness for the tracking and observation errors are guaranteed. Experimental results are included to support the developed theory. 相似文献
43.
Michel P. Tcheou André L.L. Miranda Lisandro Lovisolo Eduardo A.B. da Silva Marco A.M. Rodrigues Paulo S.R. Diniz 《Digital Signal Processing》2012,22(2):288-297
In this paper, we verify how far electric disturbance signals can be compressed without compromising the analysis of encoded fault records. A recently proposed compression algorithm, referred to as Damped Sinusoidal Matching Pursuit (DSMP) has the remarkable feature of obtaining both compact and physically interpretable representations. However, for fault analysis applications, one is primarily interested in how accurate can be the analysis performed on compressed signals, instead of evaluating mean-squared error figures. Unlike previous works in digital fault records compression, the performance of the DSMP compression method is evaluated using a protocol based on fault analysis procedures commonly performed by expert engineers. This protocol is applied for comparing the results obtained in the analysis of both uncompressed records and their compressed versions at different compression ratios. The results show that the DSMP is a reliable compression system since it achieves high compression ratios (6.4:1) without causing fault analysis misinterpretation. 相似文献
44.
Dellepiane M Marroquim R Callieri M Cignoni P Scopigno R 《IEEE transactions on visualization and computer graphics》2012,18(3):463-474
The projection of a photographic data set on a 3D model is a robust and widely applicable way to acquire appearance information of an object. The first step of this procedure is the alignment of the images on the 3D model. While any reconstruction pipeline aims at avoiding misregistration by improving camera calibrations and geometry, in practice a perfect alignment cannot always be reached. Depending on the way multiple camera images are fused on the object surface, remaining misregistrations show up either as ghosting or as discontinuities at transitions from one camera view to another. In this paper we propose a method, based on the computation of Optical Flow between overlapping images, to correct the local misalignment by determining the necessary displacement. The goal is to correct the symptoms of misregistration, instead of searching for a globally consistent mapping, which might not exist. The method scales up well with the size of the data set (both photographic and geometric) and is quite independent of the characteristics of the 3D model (topology cleanliness, parametrization, density). The method is robust and can handle real world cases that have different characteristics: low level geometric details and images that lack enough features for global optimization or manual methods. It can be applied to different mapping strategies, such as texture or per-vertex attribute encoding. 相似文献
45.
46.
Hugo Feitosa de Figueirêdo Yuri Almeida Lacerda Anselmo Cardoso de Paiva Marco Antonio Casanova Cláudio de Souza Baptista 《Multimedia Tools and Applications》2012,59(1):279-305
The recent popularity of digital cameras has posed a new problem: how to efficiently store and retrieve the very large number
of digital photos captured and chaotically stored in multiple locations without any annotation. This paper proposes an infrastructure,
called PhotoGeo, which aims at helping users with the people photo annotation, event photo annotation, storage and retrieval
of personal digital photos. To achieve the desired objective, PhotoGeo uses new algorithms that make it possible to annotate
photos with the key metadata to facilitate their retrieval, such as: the people who were shown in the photo (who); where it was captured (where); the date and time of capture (when); and the event that was captured. The paper concludes with a detailed evaluation of these algorithms. 相似文献
47.
Erik Cambria Marco Grassi Amir Hussain Catherine Havasi 《Multimedia Tools and Applications》2012,59(2):557-577
In a world in which millions of people express their opinions about commercial products in blogs, wikis, fora, chats and social networks, the distillation of knowledge from this huge amount of unstructured information can be a key factor for marketers who want to create an image or identity in the minds of their customers for their product, brand or organization. Opinion mining for product positioning, in fact, is getting a more and more popular research field but the extraction of useful information from social media is not a simple task. In this work we merge AI and Semantic Web techniques to extract, encode and represent this unstructured information. In particular, we use Sentic Computing, a multi-disciplinary approach to opinion mining and sentiment analysis, to semantically and affectively analyze text and encode results in a semantic aware format according to different web ontologies. Eventually we represent this information as an interconnected knowledge base which is browsable through a multi-faceted classification website. 相似文献
48.
Marco A. Jonker Piet S. van Roon Joop M. P. den Hartog 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,185(5):402-405
Summary The purpose of this study was to find experimental conditions for the complete solubility of collagen-free muscle proteins (CFMP) using acetone powder of Guelders ring sausage. Preliminary experiments were carried out to choose the best procedure for preparing the acetone dry powder. Two different methods of acetone extraction of minced sausage were compared. The acetone dry mass (ADM) method using continuous extraction in a Soxhlet [2] apparatus gave better results than the acetone powder (ACP) method, which used a blender [1]. The ADM method was used for further investigations. ADM was extracted with two types of sodium dodecyl sulphate (SDS), containing solvents A and B. Solvent A contains a Tris-boric acid buffer (pH 8.2) with 1.5% (m/v) SDS and 0.05% (m/v) dithioerythreitol [3]. Solvent B is a borate-chloric acid buffer (pH 9.0) with 2.0% (m/v) SDS and 1.0% (m/v) mercapto-ethanol [2]. Both solvents showed a linear relationship between the quantities of CFMP in ADM and the dissolved CFMP. The linear relationships were found between quantities of 10.0 and 30.0 mg (solution A) and of 5.0 and 30.0 mg ADM (solution B) per ml solvent. The solubility of CFMP was better in solvent B than in solution A. Completely dissolved CFMP from ADM was only obtained in the case of 5.0 mg ADM in 1.0 ml solution B. These conditions will be used in liquid chromatography experiments, the results of which will be reported later.
Supported by a grant from the Hoofdinspectie Levensmiddelen of the Ministry of Welzijn, Volksgezondheid en Cultuur 相似文献
Quantitative Aspekte zweier Verfahren für das Auflösen kollagenfreier Muskelproteine aus acetontrockenen Pulvern der Gelderschen Rauchwurst
Zusammenfassung Der Zweck dieser Untersuchungen ist, die experimentellen Bedingungen für die vollstän-dige Löslichkeit des kollagenfreien Muskelproteins (CFMP) aus dem Acetonpulver der Gelderschen Rauchwurst zu finden. Durch Vorversuche wurde die beste Arbeitsweise für das Zubereiten des Acetonpulvers gewählt. Zwei verschiedene Extraktionsverfahren mit zerkleinertem Wurstmaterial wurden miteinander verglichen. Die Methode mit der Acetontrockenmasse (ADM) mittels kontinuierlicher Extraktion [2] führte zu besseren Ergebnissen als die Methode mit Acetonpulver (ACP), wozu ein Mischgerät [1] verwendet wurde. Die ADM-Methode wurde für weitere Untersuchungen angewendet. ADM wurde mit zwei verschiedenen Extraktionslösungen von Natrium-Dodecylsulfat (SDS) (A und B) extrahiert. Lösung A enthalt einen Tris-Borsäure Puffer (pH 8,2) mit SDS (1,5%) und Dithioerithritol (0,05%) [3]. Die Lösung B enthält einen Borat-Salzsäure Puffer (pH 9,0) mit SDS (2,0%) und Mercapto-Ethanol (1,0%) [2]. Beide Extraktionslösungen zeigen ein lineares Verhalten zwischen den Mengen vom CFMP in ADM und in aufgelöstem CFMP. Diese Linearität wurde von 10,030,0 mg ADM (Lösungsmittel A) und von 5,030,0 mg ADM (Lösungsmittel B) gefunden. Die Lös-lichkeit in Lösung B ist gegeniiber Lösung A besser. Ein vollständig gelöstes CFMP aus ADM wurde nur bei der Extraktion von 5,0 mg ADM in 1,0 ml der Losung B erhalten. Diese Bedingung soll in unseren künftigen flüssigchromatographischen Experimenten verwendet werden.
Supported by a grant from the Hoofdinspectie Levensmiddelen of the Ministry of Welzijn, Volksgezondheid en Cultuur 相似文献
49.
Davide Barbagallo Angela Caponnetto Cristina Barbagallo Rosalia Battaglia Federica Mirabella Duilia Brex Michele Stella Giuseppe Broggi Roberto Altieri Francesco Certo Rosario Caltabiano Giuseppe Maria Vincenzo Barbagallo Carmelina Daniela Anfuso Gabriella Lupo Marco Ragusa Cinzia Di Pietro Thomas Birkballe Hansen Michele Purrello 《International journal of molecular sciences》2021,22(4)
Circular RNAs (circRNAs) are a large class of RNAs with regulatory functions within cells. We recently showed that circSMARCA5 is a tumor suppressor in glioblastoma multiforme (GBM) and acts as a decoy for Serine and Arginine Rich Splicing Factor 1 (SRSF1) through six predicted binding sites (BSs). Here we characterized RNA motifs functionally involved in the interaction between circSMARCA5 and SRSF1. Three different circSMARCA5 molecules (Mut1, Mut2, Mut3), each mutated in two predicted SRSF1 BSs at once, were obtained through PCR-based replacement of wild-type (WT) BS sequences and cloned in three independent pcDNA3 vectors. Mut1 significantly decreased its capability to interact with SRSF1 as compared to WT, based on the RNA immunoprecipitation assay. In silico analysis through the “Find Individual Motif Occurrences” (FIMO) algorithm showed GAUGAA as an experimentally validated SRSF1 binding motif significantly overrepresented within both predicted SRSF1 BSs mutated in Mut1 (q-value = 0.0011). U87MG and CAS-1, transfected with Mut1, significantly increased their migration with respect to controls transfected with WT, as revealed by the cell exclusion zone assay. Immortalized human brain microvascular endothelial cells (IM-HBMEC) exposed to conditioned medium (CM) harvested from U87MG and CAS-1 transfected with Mut1 significantly sprouted more than those treated with CM harvested from U87MG and CAS-1 transfected with WT, as shown by the tube formation assay. qRT-PCR showed that the intracellular pro- to anti-angiogenic Vascular Endothelial Growth Factor A (VEGFA) mRNA isoform ratio and the amount of total VEGFA mRNA secreted in CM significantly increased in Mut1-transfected CAS-1 as compared to controls transfected with WT. Our data suggest that GAUGAA is the RNA motif responsible for the interaction between circSMARCA5 and SRSF1 as well as for the circSMARCA5-mediated control of GBM cell migration and angiogenic potential. 相似文献
50.
Martijn J. C. van der Lienden Jan Aten Andr R. A. Marques Ingeborg S. E. Waas Per W. B. Larsen Nike Claessen Nicole N. van der Wel Roelof Ottenhoff Marco van Eijk Johannes M. F. G. Aerts 《International journal of molecular sciences》2021,22(5)
The lysosomal storage disease Niemann–Pick type C (NPC) is caused by impaired cholesterol efflux from lysosomes, which is accompanied by secondary lysosomal accumulation of sphingomyelin and glucosylceramide (GlcCer). Similar to Gaucher disease (GD), patients deficient in glucocerebrosidase (GCase) degrading GlcCer, NPC patients show an elevated glucosylsphingosine and glucosylated cholesterol. In livers of mice lacking the lysosomal cholesterol efflux transporter NPC1, we investigated the expression of established biomarkers of lipid-laden macrophages of GD patients, their GCase status, and content on the cytosol facing glucosylceramidase GBA2 and lysosomal integral membrane protein type B (LIMP2), a transporter of newly formed GCase to lysosomes. Livers of 80-week-old Npc1−/− mice showed a partially reduced GCase protein and enzymatic activity. In contrast, GBA2 levels tended to be reciprocally increased with the GCase deficiency. In Npc1−/− liver, increased expression of lysosomal enzymes (cathepsin D, acid ceramidase) was observed as well as increased markers of lipid-stressed macrophages (GPNMB and galectin-3). Immunohistochemistry showed that the latter markers are expressed by lipid laden Kupffer cells. Earlier reported increase of LIMP2 in Npc1−/− liver was confirmed. Unexpectedly, immunohistochemistry showed that LIMP2 is particularly overexpressed in the hepatocytes of the Npc1−/− liver. LIMP2 in these hepatocytes seems not to only localize to (endo)lysosomes. The recent recognition that LIMP2 harbors a cholesterol channel prompts the speculation that LIMP2 in Npc1−/− hepatocytes might mediate export of cholesterol into the bile and thus protects the hepatocytes. 相似文献