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排序方式: 共有222条查询结果,搜索用时 31 毫秒
211.
Memorializes J. Louin-Tapp, known particularly for her profound and lasting impact on the field of psychology and law. Her pioneering efforts in legal socialization and all of her subsequent work had at its core the theme of justice. Dr. Louin-Tapp articulated ethical principles that remain standards for the conduct of research on diverse cultures and on prisoner and other dependent populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
212.
213.
Reddy B Elibol OH Nair PR Dorvel BR Butler F Ahsan Z Bergstrom DE Alam MA Bashir R 《Analytical chemistry》2011,83(3):888-895
We demonstrate the temperature mediated applications of a previously proposed novel localized dielectric heating method on the surface of dual purpose silicon field effect transistor (FET) sensor-heaters and perform modeling and characterization of the underlying mechanisms. The FETs are first shown to operate as electrical sensors via sensitivity to changes in pH in ionic fluids. The same devices are then demonstrated as highly localized heaters via investigation of experimental heating profiles and comparison to simulation results. These results offer further insight into the heating mechanism and help determine the spatial resolution of the technique. Two important biosensor platform applications spanning different temperature ranges are then demonstrated: a localized heat-mediated DNA exchange reaction and a method for dense selective functionalization of probe molecules via the heat catalyzed complete desorption and reattachment of chemical functionalization to the transistor surfaces. Our results show that the use of silicon transistors can be extended beyond electrical switching and field-effect sensing to performing localized temperature controlled chemical reactions on the transistor itself. 相似文献
214.
Felice Crupi Raffaele De Rose Maksym Paliy Marco Lanuzza Mattia Perna Giuseppe Iannaccone 《International Journal of Circuit Theory and Applications》2018,46(4):779-795
This work proposes a new class of current references based on only 3 transistors that allows sub‐0.5 V operation. The circuit consists of a 2‐transistor block that generates a proportional‐to‐absolute‐temperature or a complementary‐to‐absolute‐temperature voltage and a load transistor. The idea of a 3T current reference is validated by circuit simulations for different complementary metal‐oxide‐semiconductor technologies and by experimental measurements on a large set of test chips fabricated with a commercial 0.18 μm complementary metal‐oxide‐semiconductor process. As compared to the state‐of‐art competitors, the 3T current reference exhibits competitive performance in terms of temperature coefficient (578 ppm/°C), line sensitivity (3.9%/V), and power consumption (213 nW) and presents a reduction by a factor of 2 to 3 in terms of minimum operating voltage (0.45 V) and an improvement of 1 to 2 orders of magnitude in terms of area occupation (750 μm2). In spite of the extremely reduced silicon area, the fabricated chips exhibit low‐process sensitivity (2.7%). A digital trimming solution to significantly reduce the process sensitivity is also presented and validated by simulations. 相似文献
215.
Patient dose in digital projection radiography 总被引:1,自引:0,他引:1
Compagnone G Pagan L Baleni MC Calzolaio FL Barozzi L Bergamini C 《Radiation protection dosimetry》2008,129(1-3):135-137
In projection radiography, two types of digital imaging systems are currently available, computed radiography (CR) and direct radiography (DR): a difference between them can be stated in terms of dose and image quality. In the Radiology Emergency Department of our hospital, a flat-panel DR equipment (Siemens Axiom Aristos FX) and two CR systems (Kodak CR-850) are employed. In 2006, five standard radiographic examinations (abdomen, chest, lumbar spine, pelvis, skull) were considered: doses delivered to patients in terms of both entrance skin dose (ESD) and effective dose (E) were calculated and compared in order to study the dosimetric discrepancies between CR and DR. Assessment of image quality is undertaken by Consultant Radiologists to ensure that the quality criteria for diagnostic radiographic images of the European guidelines were met. Results showed that both ESD and E in DR are lower than that in CR; all images met the criteria in the European Guidelines for both modalities and were used for reporting by the radiologists. Since the operators are the same and the image quality is comparable in both modalities, this study shows that in the considered examinations, DR can perform better than CR from a dosimetric point of view. 相似文献
216.
Electronic structure of single DNA molecules resolved by transverse scanning tunnelling spectroscopy
Shapir E Cohen H Calzolari A Cavazzoni C Ryndyk DA Cuniberti G Kotlyar A Di Felice R Porath D 《Nature materials》2008,7(1):68-74
Attempts to resolve the energy-level structure of single DNA molecules by scanning tunnelling spectroscopy span over the past two decades, owing to the unique ability of this technique to probe the local density of states of objects deposited on a surface. Nevertheless, success was hindered by extreme technical difficulties in stable deposition and reproducibility. Here, by using scanning tunnelling spectroscopy at cryogenic temperature, we disclose the energy spectrum of poly(G)-poly(C) DNA molecules deposited on gold. The tunnelling current-voltage (I-V) characteristics and their derivative (dI/dV-V) curves at 78 K exhibit a clear gap and a peak structure around the gap. Limited fluctuations in the I-V curves are observed and statistically characterized. By means of ab initio density functional theory calculations, the character of the observed peaks is generally assigned to groups of orbitals originating from the different molecular components, namely the nucleobases, the backbone and the counterions. 相似文献
217.
Luigi Bellocchio Alessio Danilo Inchingolo Angelo Michele Inchingolo Felice Lorusso Giuseppina Malcangi Luigi Santacroce Antonio Scarano Ioana Roxana Bordea Denisa Hazballa Maria Teresa DOria Ciro Gargiulo Isacco Ludovica Nucci Rosario Serpico Gianluca Martino Tartaglia Delia Giovanniello Maria Contaldo Marco Farronato Gianna Dipalma Francesco Inchingolo 《International journal of molecular sciences》2021,22(15)
Background: marijuana, the common name for cannabis sativa preparations, is one of the most consumed drug all over the world, both at therapeutical and recreational levels. With the legalization of medical uses of cannabis in many countries, and even its recreational use in most of these, the prevalence of marijuana use has markedly risen over the last decade. At the same time, there is also a higher prevalence in the health concerns related to cannabis use and abuse. Thus, it is mandatory for oral healthcare operators to know and deal with the consequences and effects of cannabis use on oral cavity health. This review will briefly summarize the components of cannabis and the endocannabinoid system, as well as the cellular and molecular mechanisms of biological cannabis action in human cells and biologic activities on tissues. We will also look into oropharyngeal tissue expression of cannabinoid receptors, together with a putative association of cannabis to several oral diseases. Therefore, this review will elaborate the basic biology and physiology of cannabinoids in human oral tissues with the aim of providing a better comprehension of the effects of its use and abuse on oral health, in order to include cannabinoid usage into dental patient health records as well as good medicinal practice. Methods: the paper selection was performed by PubMed/Medline and EMBASE electronic databases, and reported according to the PRISMA guidelines. The scientific products were included for qualitative analysis. Results: the paper search screened a total of 276 papers. After the initial screening and the eligibility assessment, a total of 32 articles were considered for the qualitative analysis. Conclusions: today, cannabis consumption has been correlated to a higher risk of gingival and periodontal disease, oral infection and cancer of the oral cavity, while the physico-chemical activity has not been completely clarified. Further investigations are necessary to evaluate a therapeutic efficacy of this class of drugs for the promising treatment of several different diseases of the salivary glands and oral diseases. 相似文献
218.
Nicola Antonio di Meo Davide Loizzo Savio Domenico Pandolfo Riccardo Autorino Matteo Ferro Camillo Porta Alessandro Stella Cinzia Bizzoca Leonardo Vincenti Felice Crocetto Octavian Sabin Tataru Monica Rutigliano Michele Battaglia Pasquale Ditonno Giuseppe Lucarelli 《International journal of molecular sciences》2022,23(8)
Metabolomic analysis has proven to be a useful tool in biomarker discovery and the molecular classification of cancers. In order to find new biomarkers, and to better understand its pathological behavior, bladder cancer also has been studied using a metabolomics approach. In this article, we review the literature on metabolomic studies of bladder cancer, focusing on the different available samples (urine, blood, tissue samples) used to perform the studies and their relative findings. Moreover, the multi-omic approach in bladder cancer research has found novel insights into its metabolic behavior, providing excellent start-points for new diagnostic and therapeutic strategies. Metabolomics data analysis can lead to the discovery of a “signature pathway” associated with the progression of bladder cancer; this aspect could be potentially valuable in predictions of clinical outcomes and the introduction of new treatments. However, further studies are needed to give stronger evidence and to make these tools feasible for use in clinical practice. 相似文献
219.
We are introducing a real-time variable frame rate control scheme capable of optimizing both spatial and temporal video qualities.
It traces the motion of incoming video frames and automatically tunes the outgoing frame rate according to the level of jerkiness
acceptable by the user. The control scheme was conceived within the framework of mobile communications, which require an optimum
use of both the available bandwidth and terminal resources. We have designed and implemented a video transcoding architecture
which supports our frame rate control. The transcoder has been developed at the Coritel laboratories, Rome, Italy (Coritel
is a research consortium managed by Ericsson Lab, Italy, and the University of Rome La Sapienza), while the visual tests were
carried out at the ISCOM laboratory, Italian Communication Ministry, Rome, Italy. The proposed transcoding architecture is
compatible with the constraints of real-time communications and it has been extensively tested under a wide range of conditions.
We then present a subjective assessment of our solution carried out in a fully equipped professional laboratory. Within this
assessment a number of non-expert viewers were asked to express their preference when watching side by side the same video,
coded at a variable frame rate and at a fixed frame rate. Results show that in most cases a variable frame rate control based
on a dynamic bit/frame allocation scheme might substantially improve video quality perceived by viewers.
Vittorio Baroncini received his degree in Physics in 1976. He then joined the ITTR&D Laboratory of Pomezia (Italy), as HW designer. In 1984, he joined the ‘Instituto Superiore delle Poste eTelecomunicazioni’, the technical branch of the Italian Government’s Telecommunication Ministry, where he worked in the area of national regulatory activity, dealing with line transmission system on digital networks (PDH). In 1986, he moved to the TV group of Fondazione Ugo Bordoni (FUB), working as HW designer. At the same time, he participated in international standards activities, by contributing to the works of the CCIR (now ITU-R) Committee. He also took part in the activities of the International Standards Organization (ISO) in 1992 by joining the SC29-WG11 (MPEG) group who dealt with the MPEG-2 verification tests. In 1995, he was appointed as the FUB responsible for the EU projects ‘QUOVADIS’, and ‘MOSQUITO’, both related to the automatic control of QoS in TV digital networks. In these projects he developed a new algorithm for a ‘reduced reference’ QoS metric to be applied on a digital TV network provided with a return channel. He is the designer of new subjective evaluation methods. Currently, he is in the steering board of two prominent working parties in the ITU-R: chair of WP6Q (Performance assessment and quality control) and vice-chair of TG6/9 (Digital Cinema). He is the technical in-charge for the HDTV and D-Cinema projects in FUB. He is author of many conferences and journal papers, and also the co-author of a book on MPEG-4. Renzo Felice received his M.S. degree in Electronic Engineering in 2004 from the University of Cassino, Italy. After his thesis he joined the Co.Ri.TeL. research centre, Rome, Italy, where he basically worked on video compression and transmission for real-time applications. Here he studied and developed some video transcoding techniques which allow seamless bit-rate adaptation for heterogeneous networks or for terminals with different display capabilities, while maximizing the user perceived quality. He recently joined a private company where he works in the designing and testing of electronic equipments for health care applications. Giovanni Iacovoni received his M.S. degree in Electronic Engineering in 1989 from the University of Rome La Sapienza, Italy. He then joined Ericsson Italy, where he worked as ASIC designer and embedded SW developer. In 2000 he obtained a PhD on video compression and transmission from the University of Pavia, Italy. After that he was appointed manager of the research activities on multimedia of the Innovation Department of Ericsson Lab Italy. During that period he mainly coordinated the development of prototypes for audio/video performance evaluation in IP-based networks in cooperation with Co.Ri.Tel., a research consortium between Ericsson Lab Italy and the three Universities of Rome. He recently joined CREATE-NET, a northern Italy based telecom research centre. Here, on the one hand he managed research projects on multimedia, and on the other hand he looked for funding opportunities, basically through technology transfer activities and the preparation of national and European research projects. Now he is a consultant for both CREATE-NET and the University of Rome La Sapienza. His current research interests include digital ASIC design, image/speech compression and transport, video transcoding for real-time applications, TCP analysis and traffic modelling. 相似文献
G. IacovoniEmail: |
Vittorio Baroncini received his degree in Physics in 1976. He then joined the ITTR&D Laboratory of Pomezia (Italy), as HW designer. In 1984, he joined the ‘Instituto Superiore delle Poste eTelecomunicazioni’, the technical branch of the Italian Government’s Telecommunication Ministry, where he worked in the area of national regulatory activity, dealing with line transmission system on digital networks (PDH). In 1986, he moved to the TV group of Fondazione Ugo Bordoni (FUB), working as HW designer. At the same time, he participated in international standards activities, by contributing to the works of the CCIR (now ITU-R) Committee. He also took part in the activities of the International Standards Organization (ISO) in 1992 by joining the SC29-WG11 (MPEG) group who dealt with the MPEG-2 verification tests. In 1995, he was appointed as the FUB responsible for the EU projects ‘QUOVADIS’, and ‘MOSQUITO’, both related to the automatic control of QoS in TV digital networks. In these projects he developed a new algorithm for a ‘reduced reference’ QoS metric to be applied on a digital TV network provided with a return channel. He is the designer of new subjective evaluation methods. Currently, he is in the steering board of two prominent working parties in the ITU-R: chair of WP6Q (Performance assessment and quality control) and vice-chair of TG6/9 (Digital Cinema). He is the technical in-charge for the HDTV and D-Cinema projects in FUB. He is author of many conferences and journal papers, and also the co-author of a book on MPEG-4. Renzo Felice received his M.S. degree in Electronic Engineering in 2004 from the University of Cassino, Italy. After his thesis he joined the Co.Ri.TeL. research centre, Rome, Italy, where he basically worked on video compression and transmission for real-time applications. Here he studied and developed some video transcoding techniques which allow seamless bit-rate adaptation for heterogeneous networks or for terminals with different display capabilities, while maximizing the user perceived quality. He recently joined a private company where he works in the designing and testing of electronic equipments for health care applications. Giovanni Iacovoni received his M.S. degree in Electronic Engineering in 1989 from the University of Rome La Sapienza, Italy. He then joined Ericsson Italy, where he worked as ASIC designer and embedded SW developer. In 2000 he obtained a PhD on video compression and transmission from the University of Pavia, Italy. After that he was appointed manager of the research activities on multimedia of the Innovation Department of Ericsson Lab Italy. During that period he mainly coordinated the development of prototypes for audio/video performance evaluation in IP-based networks in cooperation with Co.Ri.Tel., a research consortium between Ericsson Lab Italy and the three Universities of Rome. He recently joined CREATE-NET, a northern Italy based telecom research centre. Here, on the one hand he managed research projects on multimedia, and on the other hand he looked for funding opportunities, basically through technology transfer activities and the preparation of national and European research projects. Now he is a consultant for both CREATE-NET and the University of Rome La Sapienza. His current research interests include digital ASIC design, image/speech compression and transport, video transcoding for real-time applications, TCP analysis and traffic modelling. 相似文献
220.
Nicola Antonio di Meo Francesco Lasorsa Monica Rutigliano Davide Loizzo Matteo Ferro Alessandro Stella Cinzia Bizzoca Leonardo Vincenti Savio Domenico Pandolfo Riccardo Autorino Felice Crocetto Emanuele Montanari Marco Spilotros Michele Battaglia Pasquale Ditonno Giuseppe Lucarelli 《International journal of molecular sciences》2022,23(22)