WorldWideScience

Sample records for computer access correlations

  1. Computer self efficacy as correlate of on-line public access ...

    African Journals Online (AJOL)

    The use of Online Public Access Catalogue (OPAC) by students has a lot of advantages and computer self-efficacy is a factor that could determine its effective utilization. Little appears to be known about colleges of education students‟ use of OPAC, computer self-efficacy and the relationship between OPAC and computer ...

  2. Computer Security Systems Enable Access.

    Science.gov (United States)

    Riggen, Gary

    1989-01-01

    A good security system enables access and protects information from damage or tampering, but the most important aspects of a security system aren't technical. A security procedures manual addresses the human element of computer security. (MLW)

  3. Computer access security code system

    Science.gov (United States)

    Collins, Earl R., Jr. (Inventor)

    1990-01-01

    A security code system for controlling access to computer and computer-controlled entry situations comprises a plurality of subsets of alpha-numeric characters disposed in random order in matrices of at least two dimensions forming theoretical rectangles, cubes, etc., such that when access is desired, at least one pair of previously unused character subsets not found in the same row or column of the matrix is chosen at random and transmitted by the computer. The proper response to gain access is transmittal of subsets which complete the rectangle, and/or a parallelepiped whose opposite corners were defined by first groups of code. Once used, subsets are not used again to absolutely defeat unauthorized access by eavesdropping, and the like.

  4. Automated Computer Access Request System

    Science.gov (United States)

    Snook, Bryan E.

    2010-01-01

    The Automated Computer Access Request (AutoCAR) system is a Web-based account provisioning application that replaces the time-consuming paper-based computer-access request process at Johnson Space Center (JSC). Auto- CAR combines rules-based and role-based functionality in one application to provide a centralized system that is easily and widely accessible. The system features a work-flow engine that facilitates request routing, a user registration directory containing contact information and user metadata, an access request submission and tracking process, and a system administrator account management component. This provides full, end-to-end disposition approval chain accountability from the moment a request is submitted. By blending both rules-based and rolebased functionality, AutoCAR has the flexibility to route requests based on a user s nationality, JSC affiliation status, and other export-control requirements, while ensuring a user s request is addressed by either a primary or backup approver. All user accounts that are tracked in AutoCAR are recorded and mapped to the native operating system schema on the target platform where user accounts reside. This allows for future extensibility for supporting creation, deletion, and account management directly on the target platforms by way of AutoCAR. The system s directory-based lookup and day-today change analysis of directory information determines personnel moves, deletions, and additions, and automatically notifies a user via e-mail to revalidate his/her account access as a result of such changes. AutoCAR is a Microsoft classic active server page (ASP) application hosted on a Microsoft Internet Information Server (IIS).

  5. Dynamic computing random access memory

    International Nuclear Information System (INIS)

    Traversa, F L; Bonani, F; Pershin, Y V; Di Ventra, M

    2014-01-01

    The present von Neumann computing paradigm involves a significant amount of information transfer between a central processing unit and memory, with concomitant limitations in the actual execution speed. However, it has been recently argued that a different form of computation, dubbed memcomputing (Di Ventra and Pershin 2013 Nat. Phys. 9 200–2) and inspired by the operation of our brain, can resolve the intrinsic limitations of present day architectures by allowing for computing and storing of information on the same physical platform. Here we show a simple and practical realization of memcomputing that utilizes easy-to-build memcapacitive systems. We name this architecture dynamic computing random access memory (DCRAM). We show that DCRAM provides massively-parallel and polymorphic digital logic, namely it allows for different logic operations with the same architecture, by varying only the control signals. In addition, by taking into account realistic parameters, its energy expenditures can be as low as a few fJ per operation. DCRAM is fully compatible with CMOS technology, can be realized with current fabrication facilities, and therefore can really serve as an alternative to the present computing technology. (paper)

  6. Reliable computation from contextual correlations

    Science.gov (United States)

    Oestereich, André L.; Galvão, Ernesto F.

    2017-12-01

    An operational approach to the study of computation based on correlations considers black boxes with one-bit inputs and outputs, controlled by a limited classical computer capable only of performing sums modulo-two. In this setting, it was shown that noncontextual correlations do not provide any extra computational power, while contextual correlations were found to be necessary for the deterministic evaluation of nonlinear Boolean functions. Here we investigate the requirements for reliable computation in this setting; that is, the evaluation of any Boolean function with success probability bounded away from 1 /2 . We show that bipartite CHSH quantum correlations suffice for reliable computation. We also prove that an arbitrarily small violation of a multipartite Greenberger-Horne-Zeilinger noncontextuality inequality also suffices for reliable computation.

  7. Correlates of Access to Business Research Databases

    Science.gov (United States)

    Gottfried, John C.

    2010-01-01

    This study examines potential correlates of business research database access through academic libraries serving top business programs in the United States. Results indicate that greater access to research databases is related to enrollment in graduate business programs, but not to overall enrollment or status as a public or private institution.…

  8. Disk access controller for Multi 8 computer

    International Nuclear Information System (INIS)

    Segalard, Jean

    1970-01-01

    After having presented the initial characteristics and weaknesses of the software provided for the control of a memory disk coupled with a Multi 8 computer, the author reports the development and improvement of this controller software. He presents the different constitutive parts of the computer and the operation of the disk coupling and of the direct access to memory. He reports the development of the disk access controller: software organisation, loader, subprograms and statements

  9. Computer Access and Flowcharting as Variables in Learning Computer Programming.

    Science.gov (United States)

    Ross, Steven M.; McCormick, Deborah

    Manipulation of flowcharting was crossed with in-class computer access to examine flowcharting effects in the traditional lecture/laboratory setting and in a classroom setting where online time was replaced with manual simulation. Seventy-two high school students (24 male and 48 female) enrolled in a computer literacy course served as subjects.…

  10. Computation: A New Open Access Journal of Computational Chemistry, Computational Biology and Computational Engineering

    OpenAIRE

    Karlheinz Schwarz; Rainer Breitling; Christian Allen

    2013-01-01

    Computation (ISSN 2079-3197; http://www.mdpi.com/journal/computation) is an international scientific open access journal focusing on fundamental work in the field of computational science and engineering. Computational science has become essential in many research areas by contributing to solving complex problems in fundamental science all the way to engineering. The very broad range of application domains suggests structuring this journal into three sections, which are briefly characterized ...

  11. Embedded systems for supporting computer accessibility.

    Science.gov (United States)

    Mulfari, Davide; Celesti, Antonio; Fazio, Maria; Villari, Massimo; Puliafito, Antonio

    2015-01-01

    Nowadays, customized AT software solutions allow their users to interact with various kinds of computer systems. Such tools are generally available on personal devices (e.g., smartphones, laptops and so on) commonly used by a person with a disability. In this paper, we investigate a way of using the aforementioned AT equipments in order to access many different devices without assistive preferences. The solution takes advantage of open source hardware and its core component consists of an affordable Linux embedded system: it grabs data coming from the assistive software, which runs on the user's personal device, then, after processing, it generates native keyboard and mouse HID commands for the target computing device controlled by the end user. This process supports any operating system available on the target machine and it requires no specialized software installation; therefore the user with a disability can rely on a single assistive tool to control a wide range of computing platforms, including conventional computers and many kinds of mobile devices, which receive input commands through the USB HID protocol.

  12. Computation: A New Open Access Journal of Computational Chemistry, Computational Biology and Computational Engineering

    Directory of Open Access Journals (Sweden)

    Karlheinz Schwarz

    2013-09-01

    Full Text Available Computation (ISSN 2079-3197; http://www.mdpi.com/journal/computation is an international scientific open access journal focusing on fundamental work in the field of computational science and engineering. Computational science has become essential in many research areas by contributing to solving complex problems in fundamental science all the way to engineering. The very broad range of application domains suggests structuring this journal into three sections, which are briefly characterized below. In each section a further focusing will be provided by occasionally organizing special issues on topics of high interests, collecting papers on fundamental work in the field. More applied papers should be submitted to their corresponding specialist journals. To help us achieve our goal with this journal, we have an excellent editorial board to advise us on the exciting current and future trends in computation from methodology to application. We very much look forward to hearing all about the research going on across the world. [...

  13. Growth rate correlates negatively with protein turnover in Arabidopsis accessions.

    Science.gov (United States)

    Ishihara, Hirofumi; Moraes, Thiago Alexandre; Pyl, Eva-Theresa; Schulze, Waltraud X; Obata, Toshihiro; Scheffel, André; Fernie, Alisdair R; Sulpice, Ronan; Stitt, Mark

    2017-08-01

    Previous studies with Arabidopsis accessions revealed that biomass correlates negatively to dusk starch content and total protein, and positively to the maximum activities of enzymes in photosynthesis. We hypothesized that large accessions have lower ribosome abundance and lower rates of protein synthesis, and that this is compensated by lower rates of protein degradation. This would increase growth efficiency and allow more investment in photosynthetic machinery. We analysed ribosome abundance and polysome loading in 19 accessions, modelled the rates of protein synthesis and compared them with the observed rate of growth. Large accessions contained less ribosomes than small accessions, due mainly to cytosolic ribosome abundance falling at night in large accessions. The modelled rates of protein synthesis resembled those required for growth in large accessions, but were up to 30% in excess in small accessions. We then employed 13 CO 2 pulse-chase labelling to measure the rates of protein synthesis and degradation in 13 accessions. Small accessions had a slightly higher rate of protein synthesis and much higher rates of protein degradation than large accessions. Protein turnover was negligible in large accessions but equivalent to up to 30% of synthesised protein day -1 in small accessions. We discuss to what extent the decrease in growth in small accessions can be quantitatively explained by known costs of protein turnover and what factors may lead to the altered diurnal dynamics and increase of ribosome abundance in small accessions, and propose that there is a trade-off between protein turnover and maximisation of growth rate. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  14. Equity and Computers for Mathematics Learning: Access and Attitudes

    Science.gov (United States)

    Forgasz, Helen J.

    2004-01-01

    Equity and computer use for secondary mathematics learning was the focus of a three year study. In 2003, a survey was administered to a large sample of grade 7-10 students. Some of the survey items were aimed at determining home access to and ownership of computers, and students' attitudes to mathematics, computers, and computer use for…

  15. Encapsulating peritonitis: computed tomography and surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kadow, Juliana Santos; Fingerhut, Carla Jeronimo Peres; Fernandes, Vinicius de Barros; Coradazzi, Klaus Rizk Stuhr; Silva, Lucas Marciel Soares; Penachim, Thiago Jose, E-mail: vinicius.barros.fernandes@gmail.com [Pontificia Universidade Catolica de Campinas (PUC-Campinas), Campinas, SP (Brazil). Hospital e Maternidade Celso Pierro

    2014-07-15

    Sclerosing encapsulating peritonitis is a rare and frequently severe entity characterized by total or partial involvement of small bowel loops by a membrane of fibrous tissue. The disease presents with nonspecific clinical features of intestinal obstruction, requiring precise imaging diagnosis to guide the treatment. The present report emphasizes the importance of computed tomography in the diagnosis of this condition and its confirmation by surgical correlation. (author)

  16. Towards an Approach of Semantic Access Control for Cloud Computing

    Science.gov (United States)

    Hu, Luokai; Ying, Shi; Jia, Xiangyang; Zhao, Kai

    With the development of cloud computing, the mutual understandability among distributed Access Control Policies (ACPs) has become an important issue in the security field of cloud computing. Semantic Web technology provides the solution to semantic interoperability of heterogeneous applications. In this paper, we analysis existing access control methods and present a new Semantic Access Control Policy Language (SACPL) for describing ACPs in cloud computing environment. Access Control Oriented Ontology System (ACOOS) is designed as the semantic basis of SACPL. Ontology-based SACPL language can effectively solve the interoperability issue of distributed ACPs. This study enriches the research that the semantic web technology is applied in the field of security, and provides a new way of thinking of access control in cloud computing.

  17. Sign Compute Resolve for Random Access

    DEFF Research Database (Denmark)

    Goseling, Jasper; Stefanovic, Cedomir; Popovski, Petar

    2014-01-01

    users collide. We measure the performance of the proposed method in terms of user resolution rate as well as overall throughput of the system. The results show that our approach significantly increases the performance of the system even compared to coded random access, where collisions are not wasted......We present an approach to random access that is based on three elements: physical-layer network coding, signature codes and tree splitting. Upon occurrence of a collision, physical-layer network coding enables the receiver to decode the sum of the information that was transmitted by the individual...

  18. Gender, Computer Access and Use as Predictors of Nigerian ...

    African Journals Online (AJOL)

    This study X-rayed the contributions of gender, access to computer and computer use to the Nigerian undergraduates' computer proficiency. Three hundred and fifteen (315) undergraduates from the Faculty of Education of. Olabisi Onabanjo University, Nigeria served as the sample for this study. The instruments used for ...

  19. Predictive access control for distributed computation

    DEFF Research Database (Denmark)

    Yang, Fan; Hankin, Chris; Nielson, Flemming

    2013-01-01

    We show how to use aspect-oriented programming to separate security and trust issues from the logical design of mobile, distributed systems. The main challenge is how to enforce various types of security policies, in particular predictive access control policies — policies based on the future beh...... behavior of a program. A novel feature of our approach is that we can define policies concerning secondary use of data....

  20. Legal, privacy, security, access and regulatory issues in cloud computing

    CSIR Research Space (South Africa)

    Dlodlo, N

    2011-04-01

    Full Text Available a gap on reporting are on are legal , privacy, security, access and regulatory issues. This paper raises an awareness of legal, privacy, security, access and regulatory issues that are associated with the advent of cloud computing. An in...

  1. Higher order correlations in computed particle distributions

    International Nuclear Information System (INIS)

    Hanerfeld, H.; Herrmannsfeldt, W.; Miller, R.H.

    1989-03-01

    The rms emittances calculated for beam distributions using computer simulations are frequently dominated by higher order aberrations. Thus there are substantial open areas in the phase space plots. It has long been observed that the rms emittance is not an invariant to beam manipulations. The usual emittance calculation removes the correlation between transverse displacement and transverse momentum. In this paper, we explore the possibility of defining higher order correlations that can be removed from the distribution to result in a lower limit to the realizable emittance. The intent is that by inserting the correct combinations of linear lenses at the proper position, the beam may recombine in a way that cancels the effects of some higher order forces. An example might be the non-linear transverse space charge forces which cause a beam to spread. If the beam is then refocused so that the same non-linear forces reverse the inward velocities, the resulting phase space distribution may reasonably approximate the original distribution. The approach to finding the location and strength of the proper lens to optimize the transported beam is based on work by Bruce Carlsten of Los Alamos National Laboratory. 11 refs., 4 figs

  2. Does Technical Success of Angioplasty in Dysfunctional Hemodialysis Accesses Correlate with Access Patency?

    Energy Technology Data Exchange (ETDEWEB)

    Sidhu, Arshdeep; Tan, Kong T.; Noel-Lamy, Maxime; Simons, Martin E.; Rajan, Dheeraj K., E-mail: dheeraj.rajan@uhn.ca [University Health Network, University of Toronto, Division of Vascular and Interventional Radiology, Peter Munk Cardiac Center (Canada)

    2016-10-15

    PurposeTo study if <30 % residual stenosis post angioplasty (PTA) correlates with primary access circuit patency, and if any variables predict technical success.Materials and MethodsA prospective observational study was performed between January 2009 and December 2012, wherein 76 patients underwent 154 PTA events in 56 prosthetic grafts (AVG) and 98 autogenous fistulas (AVF). Data collected included patient age, gender, lesion location and laterality, access type and location, number of prior interventions, and transonic flow rates pre- and postintervention. Impact of technical outcome on access patency was assessed. Univariate logistic regression was used to assess the impact of variables on technical success with significant factors assessed with a multiple variable model.ResultsTechnical success rates of PTA in AVFs and AVGs were 79.6 and 76.7 %, respectively. Technical failures of PTA were associated with an increased risk of patency loss among circuits with AVFs (p < 0.05), but not with AVGs (p = 0.7). In AVFs, primary access patency rates between technical successes and failures at three and 6 months were 74.4 versus 61.9 % (p = 0.3) and 53.8 versus 23.8 % (p < 0.05), respectively. In AVGs, primary access patency rates between technical successes and failures at three and six months were 72.1 versus 53.9 % (p = 0.5) and 33.6 versus 38.5 % (p = 0.8), respectively. Transonic flow rates did not significantly differ among technically successful or failed outcomes at one or three months.ConclusionTechnical failures of PTA had a significant impact on access patency among AVFs with a trend toward poorer access patency within AVGs.

  3. Does Technical Success of Angioplasty in Dysfunctional Hemodialysis Accesses Correlate with Access Patency?

    International Nuclear Information System (INIS)

    Sidhu, Arshdeep; Tan, Kong T.; Noel-Lamy, Maxime; Simons, Martin E.; Rajan, Dheeraj K.

    2016-01-01

    PurposeTo study if <30 % residual stenosis post angioplasty (PTA) correlates with primary access circuit patency, and if any variables predict technical success.Materials and MethodsA prospective observational study was performed between January 2009 and December 2012, wherein 76 patients underwent 154 PTA events in 56 prosthetic grafts (AVG) and 98 autogenous fistulas (AVF). Data collected included patient age, gender, lesion location and laterality, access type and location, number of prior interventions, and transonic flow rates pre- and postintervention. Impact of technical outcome on access patency was assessed. Univariate logistic regression was used to assess the impact of variables on technical success with significant factors assessed with a multiple variable model.ResultsTechnical success rates of PTA in AVFs and AVGs were 79.6 and 76.7 %, respectively. Technical failures of PTA were associated with an increased risk of patency loss among circuits with AVFs (p < 0.05), but not with AVGs (p = 0.7). In AVFs, primary access patency rates between technical successes and failures at three and 6 months were 74.4 versus 61.9 % (p = 0.3) and 53.8 versus 23.8 % (p < 0.05), respectively. In AVGs, primary access patency rates between technical successes and failures at three and six months were 72.1 versus 53.9 % (p = 0.5) and 33.6 versus 38.5 % (p = 0.8), respectively. Transonic flow rates did not significantly differ among technically successful or failed outcomes at one or three months.ConclusionTechnical failures of PTA had a significant impact on access patency among AVFs with a trend toward poorer access patency within AVGs.

  4. Secure Dynamic access control scheme of PHR in cloud computing.

    Science.gov (United States)

    Chen, Tzer-Shyong; Liu, Chia-Hui; Chen, Tzer-Long; Chen, Chin-Sheng; Bau, Jian-Guo; Lin, Tzu-Ching

    2012-12-01

    With the development of information technology and medical technology, medical information has been developed from traditional paper records into electronic medical records, which have now been widely applied. The new-style medical information exchange system "personal health records (PHR)" is gradually developed. PHR is a kind of health records maintained and recorded by individuals. An ideal personal health record could integrate personal medical information from different sources and provide complete and correct personal health and medical summary through the Internet or portable media under the requirements of security and privacy. A lot of personal health records are being utilized. The patient-centered PHR information exchange system allows the public autonomously maintain and manage personal health records. Such management is convenient for storing, accessing, and sharing personal medical records. With the emergence of Cloud computing, PHR service has been transferred to storing data into Cloud servers that the resources could be flexibly utilized and the operation cost can be reduced. Nevertheless, patients would face privacy problem when storing PHR data into Cloud. Besides, it requires a secure protection scheme to encrypt the medical records of each patient for storing PHR into Cloud server. In the encryption process, it would be a challenge to achieve accurately accessing to medical records and corresponding to flexibility and efficiency. A new PHR access control scheme under Cloud computing environments is proposed in this study. With Lagrange interpolation polynomial to establish a secure and effective PHR information access scheme, it allows to accurately access to PHR with security and is suitable for enormous multi-users. Moreover, this scheme also dynamically supports multi-users in Cloud computing environments with personal privacy and offers legal authorities to access to PHR. From security and effectiveness analyses, the proposed PHR access

  5. Computer Security: When a person leaves - access rights remain!

    CERN Multimedia

    Computer Security Team

    2014-01-01

    We have been contacted recently by an embarrassed project manager who just figured out that a student who left at the end of 2013 still had access rights to read the whole project folder in February 2014: “How can that be?! In any other company, access rights would be purged at the same time as an employment contract terminates." Not so at CERN.   CERN has always been an open site with an open community. Physical access to the site is lightweight and you just need to have your CERN access card at hand. Further restrictions have only been put in place where safety or security really require them, and CERN does not require you to keep your access card on display. The same holds for the digital world. Once registered at CERN - either by contract, via your experiment or through the Users' office - you own a computing account that provides you with access to a wide variety of computing services. For example, last year 9,730 students/technicians/engineers/researchers/sta...

  6. Distributed Database Access in the LHC Computing Grid with CORAL

    CERN Document Server

    Molnár, Z; Düllmann, D; Giacomo, G; Kalkhof, A; Valassi, A; CERN. Geneva. IT Department

    2009-01-01

    The CORAL package is the LCG Persistency Framework foundation for accessing relational databases. From the start CORAL has been designed to facilitate the deployment of the LHC experiment database applications in a distributed computing environment. In particular we cover - improvements to database service scalability by client connection management - platform-independent, multi-tier scalable database access by connection multiplexing, caching - a secure authentication and authorisation scheme integrated with existing grid services. We will summarize the deployment experience from several experiment productions using the distributed database infrastructure, which is now available in LCG. Finally, we present perspectives for future developments in this area.

  7. Matching and correlation computations in stereoscopic depth perception.

    Science.gov (United States)

    Doi, Takahiro; Tanabe, Seiji; Fujita, Ichiro

    2011-03-02

    A fundamental task of the visual system is to infer depth by using binocular disparity. To encode binocular disparity, the visual cortex performs two distinct computations: one detects matched patterns in paired images (matching computation); the other constructs the cross-correlation between the images (correlation computation). How the two computations are used in stereoscopic perception is unclear. We dissociated their contributions in near/far discrimination by varying the magnitude of the disparity across separate sessions. For small disparity (0.03°), subjects performed at chance level to a binocularly opposite-contrast (anti-correlated) random-dot stereogram (RDS) but improved their performance with the proportion of contrast-matched (correlated) dots. For large disparity (0.48°), the direction of perceived depth reversed with an anti-correlated RDS relative to that for a correlated one. Neither reversed nor normal depth was perceived when anti-correlation was applied to half of the dots. We explain the decision process as a weighted average of the two computations, with the relative weight of the correlation computation increasing with the disparity magnitude. We conclude that matching computation dominates fine depth perception, while both computations contribute to coarser depth perception. Thus, stereoscopic depth perception recruits different computations depending on the disparity magnitude.

  8. Computer self-efficacy and computer attitude as correlates of ...

    African Journals Online (AJOL)

    The Internet as a useful tool that supports teaching and learning is not in full use in most secondary schools in Nigeria hence limiting the students from maximizing the potentials of Internet in advancing their academic pursuits. This study, therefore, examined the extent to which computer self-efficacy and computer attitude ...

  9. Towards ubiquitous access of computer-assisted surgery systems.

    Science.gov (United States)

    Liu, Hui; Lufei, Hanping; Shi, Weishong; Chaudhary, Vipin

    2006-01-01

    Traditional stand-alone computer-assisted surgery (CAS) systems impede the ubiquitous and simultaneous access by multiple users. With advances in computing and networking technologies, ubiquitous access to CAS systems becomes possible and promising. Based on our preliminary work, CASMIL, a stand-alone CAS server developed at Wayne State University, we propose a novel mobile CAS system, UbiCAS, which allows surgeons to retrieve, review and interpret multimodal medical images, and to perform some critical neurosurgical procedures on heterogeneous devices from anywhere at anytime. Furthermore, various optimization techniques, including caching, prefetching, pseudo-streaming-model, and compression, are used to guarantee the QoS of the UbiCAS system. UbiCAS enables doctors at remote locations to actively participate remote surgeries, share patient information in real time before, during, and after the surgery.

  10. Computer Access and Computer Use for Science Performance of Racial and Linguistic Minority Students

    Science.gov (United States)

    Chang, Mido; Kim, Sunha

    2009-01-01

    This study examined the effects of computer access and computer use on the science achievement of elementary school students, with focused attention on the effects for racial and linguistic minority students. The study used the Early Childhood Longitudinal Study (ECLS-K) database and conducted statistical analyses with proper weights and…

  11. An Annotated and Cross-Referenced Bibliography on Computer Security and Access Control in Computer Systems.

    Science.gov (United States)

    Bergart, Jeffrey G.; And Others

    This paper represents a careful study of published works on computer security and access control in computer systems. The study includes a selective annotated bibliography of some eighty-five important published results in the field and, based on these papers, analyzes the state of the art. In annotating these works, the authors try to be…

  12. Chronic rhinosinusitis: correlation of symptoms with computed ...

    African Journals Online (AJOL)

    Introduction: Symptomatology, nasal endoscopy and Computerised Tomographic (CT) scan have been used to diagnose chronic rhinosinusitis. The value of disease severity score in the assessment of chronic rhinosinusitis has not been well investigated. Hence, this study aims to correlate the pre-operative symptom ...

  13. Computer network access to scientific information systems for minority universities

    Science.gov (United States)

    Thomas, Valerie L.; Wakim, Nagi T.

    1993-08-01

    The evolution of computer networking technology has lead to the establishment of a massive networking infrastructure which interconnects various types of computing resources at many government, academic, and corporate institutions. A large segment of this infrastructure has been developed to facilitate information exchange and resource sharing within the scientific community. The National Aeronautics and Space Administration (NASA) supports both the development and the application of computer networks which provide its community with access to many valuable multi-disciplinary scientific information systems and on-line databases. Recognizing the need to extend the benefits of this advanced networking technology to the under-represented community, the National Space Science Data Center (NSSDC) in the Space Data and Computing Division at the Goddard Space Flight Center has developed the Minority University-Space Interdisciplinary Network (MU-SPIN) Program: a major networking and education initiative for Historically Black Colleges and Universities (HBCUs) and Minority Universities (MUs). In this paper, we will briefly explain the various components of the MU-SPIN Program while highlighting how, by providing access to scientific information systems and on-line data, it promotes a higher level of collaboration among faculty and students and NASA scientists.

  14. Concordance-based Kendall's Correlation for Computationally-Light vs. Computationally-Heavy Centrality Metrics: Lower Bound for Correlation

    Directory of Open Access Journals (Sweden)

    Natarajan Meghanathan

    2017-01-01

    Full Text Available We identify three different levels of correlation (pair-wise relative ordering, network-wide ranking and linear regression that could be assessed between a computationally-light centrality metric and a computationally-heavy centrality metric for real-world networks. The Kendall's concordance-based correlation measure could be used to quantitatively assess how well we could consider the relative ordering of two vertices vi and vj with respect to a computationally-light centrality metric as the relative ordering of the same two vertices with respect to a computationally-heavy centrality metric. We hypothesize that the pair-wise relative ordering (concordance-based assessment of the correlation between centrality metrics is the most strictest of all the three levels of correlation and claim that the Kendall's concordance-based correlation coefficient will be lower than the correlation coefficient observed with the more relaxed levels of correlation measures (linear regression-based Pearson's product-moment correlation coefficient and the network wide ranking-based Spearman's correlation coefficient. We validate our hypothesis by evaluating the three correlation coefficients between two sets of centrality metrics: the computationally-light degree and local clustering coefficient complement-based degree centrality metrics and the computationally-heavy eigenvector centrality, betweenness centrality and closeness centrality metrics for a diverse collection of 50 real-world networks.

  15. Survey of Canadian Myotonic Dystrophy Patients' Access to Computer Technology.

    Science.gov (United States)

    Climans, Seth A; Piechowicz, Christine; Koopman, Wilma J; Venance, Shannon L

    2017-09-01

    Myotonic dystrophy type 1 is an autosomal dominant condition affecting distal hand strength, energy, and cognition. Increasingly, patients and families are seeking information online. An online neuromuscular patient portal under development can help patients access resources and interact with each other regardless of location. It is unknown how individuals living with myotonic dystrophy interact with technology and whether barriers to access exist. We aimed to characterize technology use among participants with myotonic dystrophy and to determine whether there is interest in a patient portal. Surveys were mailed to 156 participants with myotonic dystrophy type 1 registered with the Canadian Neuromuscular Disease Registry. Seventy-five participants (60% female) responded; almost half were younger than 46 years. Most (84%) used the internet; almost half of the responders (47%) used social media. The complexity and cost of technology were commonly cited reasons not to use technology. The majority of responders (76%) were interested in a myotonic dystrophy patient portal. Patients in a Canada-wide registry of myotonic dystrophy have access to and use technology such as computers and mobile phones. These patients expressed interest in a portal that would provide them with an opportunity to network with others with myotonic dystrophy and to access information about the disease.

  16. Human- and computer-accessible 2D correlation data for a more reliable structure determination of organic compounds. Future roles of researchers, software developers, spectrometer managers, journal editors, reviewers, publisher and database managers toward artificial-intelligence analysis of NMR spectra.

    Science.gov (United States)

    Jeannerat, Damien

    2017-01-01

    The introduction of a universal data format to report the correlation data of 2D NMR spectra such as COSY, HSQC and HMBC spectra will have a large impact on the reliability of structure determination of small organic molecules. These lists of assigned cross peaks will bridge signals found in NMR 1D and 2D spectra and the assigned chemical structure. The record could be very compact, human and computer readable so that it can be included in the supplementary material of publications and easily transferred into databases of scientific literature and chemical compounds. The records will allow authors, reviewers and future users to test the consistency and, in favorable situations, the uniqueness of the assignment of the correlation data to the associated chemical structures. Ideally, the data format of the correlation data should include direct links to the NMR spectra to make it possible to validate their reliability and allow direct comparison of spectra. In order to take the full benefits of their potential, the correlation data and the NMR spectra should therefore follow any manuscript in the review process and be stored in open-access database after publication. Keeping all NMR spectra, correlation data and assigned structures together at all time will allow the future development of validation tools increasing the reliability of past and future NMR data. This will facilitate the development of artificial intelligence analysis of NMR spectra by providing a source of data than can be used efficiently because they have been validated or can be validated by future users. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  17. An accessibility solution of cloud computing by solar energy

    Directory of Open Access Journals (Sweden)

    Zuzana Priščáková

    2013-01-01

    Full Text Available Cloud computing is a modern innovative technology of solution of a problem with data storage, data processing, company infrastructure building and so on. Many companies worry over the changes by the implementation of this solution because these changes could have a negative impact on the company, or, in the case of establishment of new companies, this worry results from an unfamiliar environment. Data accessibility, integrity and security belong among basic problems of cloud computing. The aim of this paper is to offer and scientifically confirm a proposal of an accessibility solution of cloud by implementing of solar energy as a primary source. Problems with accessibility rise from power failures when data may be stolen or lost. Since cloud is often started from a server, the server dependence on power is strong. Modern conditions offer us a new, more innovative solution regarding the ecological as well as an economical company solution. The Sun as a steady source of energy offers us a possibility to produce necessary energy by a solar technique – solar panels. The connection of a solar panel as a primary source of energy for a server would remove its power dependence as well as possible failures. The power dependence would stay as a secondary source. Such an ecological solution would influence the economical side of company because the energy consumption would be lower. Besides a proposal of an accessibility solution, this paper involves a physical and mathematical solution to a calculation of solar energy showered on the Earth, a calculation of the panel size by cosines method and a simulation of these calculations in MATLAB conditions.

  18. Information Accessibility and Utilization as Correlate of Quality Of ...

    African Journals Online (AJOL)

    The quality of life of people in developing countries, including Nigeria, is often adjudged to be lower than the expected standard. This is worse with women living in the rural areas whose lives are characterised by inadequate access and use of basic amenities of life. The situation is compounded by the women's lack of ...

  19. Efficient quantum algorithm for computing n-time correlation functions.

    Science.gov (United States)

    Pedernales, J S; Di Candia, R; Egusquiza, I L; Casanova, J; Solano, E

    2014-07-11

    We propose a method for computing n-time correlation functions of arbitrary spinorial, fermionic, and bosonic operators, consisting of an efficient quantum algorithm that encodes these correlations in an initially added ancillary qubit for probe and control tasks. For spinorial and fermionic systems, the reconstruction of arbitrary n-time correlation functions requires the measurement of two ancilla observables, while for bosonic variables time derivatives of the same observables are needed. Finally, we provide examples applicable to different quantum platforms in the frame of the linear response theory.

  20. Path Not Found: Disparities in Access to Computer Science Courses in California High Schools

    Science.gov (United States)

    Martin, Alexis; McAlear, Frieda; Scott, Allison

    2015-01-01

    "Path Not Found: Disparities in Access to Computer Science Courses in California High Schools" exposes one of the foundational causes of underrepresentation in computing: disparities in access to computer science courses in California's public high schools. This report provides new, detailed data on these disparities by student body…

  1. Effect of correlated decay on fault-tolerant quantum computation

    Science.gov (United States)

    Lemberger, B.; Yavuz, D. D.

    2017-12-01

    We analyze noise in the circuit model of quantum computers when the qubits are coupled to a common bosonic bath and discuss the possible failure of scalability of quantum computation. Specifically, we investigate correlated (super-radiant) decay between the qubit energy levels from a two- or three-dimensional array of qubits without imposing any restrictions on the size of the sample. We first show that regardless of how the spacing between the qubits compares with the emission wavelength, correlated decay produces errors outside the applicability of the threshold theorem. This is because the sum of the norms of the two-body interaction Hamiltonians (which can be viewed as the upper bound on the single-qubit error) that decoheres each qubit scales with the total number of qubits and is unbounded. We then discuss two related results: (1) We show that the actual error (instead of the upper bound) on each qubit scales with the number of qubits. As a result, in the limit of large number of qubits in the computer, N →∞ , correlated decay causes each qubit in the computer to decohere in ever shorter time scales. (2) We find the complete eigenvalue spectrum of the exchange Hamiltonian that causes correlated decay in the same limit. We show that the spread of the eigenvalue distribution grows faster with N compared to the spectrum of the unperturbed system Hamiltonian. As a result, as N →∞ , quantum evolution becomes completely dominated by the noise due to correlated decay. These results argue that scalable quantum computing may not be possible in the circuit model in a two- or three- dimensional geometry when the qubits are coupled to a common bosonic bath.

  2. Lexical access in sign language: a computational model.

    Science.gov (United States)

    Caselli, Naomi K; Cohen-Goldberg, Ariel M

    2014-01-01

    PSYCHOLINGUISTIC THEORIES HAVE PREDOMINANTLY BEEN BUILT UPON DATA FROM SPOKEN LANGUAGE, WHICH LEAVES OPEN THE QUESTION: How many of the conclusions truly reflect language-general principles as opposed to modality-specific ones? We take a step toward answering this question in the domain of lexical access in recognition by asking whether a single cognitive architecture might explain diverse behavioral patterns in signed and spoken language. Chen and Mirman (2012) presented a computational model of word processing that unified opposite effects of neighborhood density in speech production, perception, and written word recognition. Neighborhood density effects in sign language also vary depending on whether the neighbors share the same handshape or location. We present a spreading activation architecture that borrows the principles proposed by Chen and Mirman (2012), and show that if this architecture is elaborated to incorporate relatively minor facts about either (1) the time course of sign perception or (2) the frequency of sub-lexical units in sign languages, it produces data that match the experimental findings from sign languages. This work serves as a proof of concept that a single cognitive architecture could underlie both sign and word recognition.

  3. Lexical access in sign language: A computational model

    Directory of Open Access Journals (Sweden)

    Naomi Kenney Caselli

    2014-05-01

    Full Text Available Psycholinguistic theories have predominantly been built upon data from spoken language, which leaves open the question: How many of the conclusions truly reflect language-general principles as opposed to modality-specific ones? We take a step toward answering this question in the domain of lexical access in recognition by asking whether a single cognitive architecture might explain diverse behavioral patterns in signed and spoken language. Chen and Mirman (2012 presented a computational model of word processing that unified opposite effects of neighborhood density in speech production, perception, and written word recognition. Neighborhood density effects in sign language also vary depending on whether the neighbors share the same handshape or location. We present a spreading activation architecture that borrows the principles proposed by Chen and Mirman (2012, and show that if this architecture is elaborated to incorporate relatively minor facts about either 1 the time course of sign perception or 2 the frequency of sub-lexical units in sign languages, it produces data that match the experimental findings from sign languages. This work serves as a proof of concept that a single cognitive architecture could underlie both sign and word recognition.

  4. Global Pattern of Nasopharyngeal Cancer: Correlation of Outcome With Access to Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Ka-On [Clinical Oncology Center, University of Hong Kong-Shenzhen Hospital, Shenzhen (China); Lee, Anne W.M., E-mail: annelee@hku-szh.org [Clinical Oncology Center, University of Hong Kong-Shenzhen Hospital, Shenzhen (China); Choi, Cheuk-Wai [Department of Systems Engineering and Engineering Management, City University of Hong Kong, Hong Kong (China); Sze, Henry C.K. [Clinical Oncology Center, University of Hong Kong-Shenzhen Hospital, Shenzhen (China); Zietman, Anthony L. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Hopkins, Kirsten I.; Rosenblatt, Eduardo [International Atomic Energy Agency, Vienna (Austria)

    2016-04-01

    Purpose: This study aimed to estimate the treatment outcome of nasopharyngeal cancer (NPC) across the world and its correlation with access to radiation therapy (RT). Methods and Materials: The age-standardized mortality (ASM) and age-standardized incidence (ASI) rates of NPC from GLOBOCAN (2012) were summarized, and [1−(ASM/ASI)] was computed to give the proxy relative survival (RS). Data from the International Atomic Energy Agency (IAEA) and the World Bank were used to assess the availability of RT in surrogate terms: the number of RT equipment units and radiation oncologists per million population. Results: A total of 112 countries with complete valid data were analyzed, and the proxy RS varied widely from 0% to 83% (median, 50%). Countries were categorized into Good, Median, and Poor outcome groups on the basis of their proxy RS (<45%, 45%-55%, and >55%). Eighty percent of new cases occurred in the Poor outcome group. Univariable linear regression showed a significant correlation between outcome and the availability of RT: proxy RS increased at 3.4% (P<.001) and 1.5% (P=.001) per unit increase in RT equipment and oncologist per million population, respectively. The median number of RT equipment units per million population increased significantly from 0.5 in the Poor, to 1.5 in the Median, to 4.6 in the Good outcome groups, and the corresponding number of oncologists increased from 1.1 to 3.3 to 7.1 (P<.001). Conclusions: Nasopharyngeal cancer is a highly treatable disease, but the outcome varies widely across the world. The current study shows a significant correlation between survival and access to RT based on available surrogate indicators. However, the possible reasons for poor outcome are likely to be multifactorial and complex. Concerted international efforts are needed not only to address the fundamental requirement for adequate RT access but also to obtain more comprehensive and accurate data for research to improve cancer outcome.

  5. An SPSS Macro to Compute Confidence Intervals for Pearson’s Correlation

    Directory of Open Access Journals (Sweden)

    Bruce Weaver

    2014-04-01

    Full Text Available In many disciplines, including psychology, medical research, epidemiology and public health, authors are required, or at least encouraged to report confidence intervals (CIs along with effect size estimates. Many students and researchers in these areas use IBM-SPSS for statistical analysis. Unfortunately, the CORRELATIONS procedure in SPSS does not provide CIs in the output. Various work-around solutions have been suggested for obtaining CIs for rhowith SPSS, but most of them have been sub-optimal. Since release 18, it has been possible to compute bootstrap CIs, but only if users have the optional bootstrap module. The !rhoCI macro described in this article is accessible to all SPSS users with release 14 or later. It directs output from the CORRELATIONS procedure to another dataset, restructures that dataset to have one row per correlation, computes a CI for each correlation, and displays the results in a single table. Because the macro uses the CORRELATIONS procedure, it allows users to specify a list of two or more variables to include in the correlation matrix, to choose a confidence level, and to select either listwise or pairwise deletion. Thus, it offers substantial improvements over previous solutions to theproblem of how to compute CIs for rho with SPSS.

  6. 76 FR 37111 - Access to Confidential Business Information by Computer Sciences Corporation and Its Identified...

    Science.gov (United States)

    2011-06-24

    ... Business Information by Computer Sciences Corporation and Its Identified Subcontractors AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has authorized its contractor, Computer Sciences Corporation of Chantilly, VA and Its Identified Subcontractors, to access information which has...

  7. Identity based Encryption and Biometric Authentication Scheme for Secure Data Access in Cloud Computing

    DEFF Research Database (Denmark)

    Cheng, Hongbing; Rong, Chunming; Tan, Zheng-Hua

    2012-01-01

    Cloud computing will be a main information infrastructure in the future; it consists of many large datacenters which are usually geographically distributed and heterogeneous. How to design a secure data access for cloud computing platform is a big challenge. In this paper, we propose a secure data...... access scheme based on identity-based encryption and biometric authentication for cloud computing. Firstly, we describe the security concern of cloud computing and then propose an integrated data access scheme for cloud computing, the procedure of the proposed scheme include parameter setup, key...... distribution, feature template creation, cloud data processing and secure data access control. Finally, we compare the proposed scheme with other schemes through comprehensive analysis and simulation. The results show that the proposed data access scheme is feasible and secure for cloud computing....

  8. On the impossibility of creating the quantum correlations with computer

    International Nuclear Information System (INIS)

    Vinduska, M.

    1991-01-01

    It is indicated that Feynman's proof about the impossibility of creating the quantum correlations with computers does not hold if the general transformations of the probability measure of the treated systems do not for a group. In the paper the consequences of this fact are considered in relation to the Bell inequalities and to the models of relative probability measure on the concave surfaces. 5 refs.; 4 figs.; 2 tabs

  9. Paracoccidioidomycosis: High-resolution computed tomography-pathologic correlation

    International Nuclear Information System (INIS)

    Marchiori, Edson; Valiante, Paulo Marcos; Mano, Claudia Mauro; Zanetti, Glaucia; Escuissato, Dante L.; Souza, Arthur Soares; Capone, Domenico

    2011-01-01

    Objective: The purpose of this study was to describe the high-resolution computed tomography (HRCT) features of pulmonary paracoccidioidomycosis and to correlate them with pathologic findings. Methods: The study included 23 adult patients with pulmonary paracoccidioidomycosis. All patients had undergone HRCT, and the images were retrospectively analyzed by two chest radiologists, who reached decisions by consensus. An experienced lung pathologist reviewed all pathological specimens. The HRCT findings were correlated with histopathologic data. Results: The predominant HRCT findings included areas of ground-glass opacities, nodules, interlobular septal thickening, airspace consolidation, cavitation, and fibrosis. The main pathological features consisted of alveolar and interlobular septal inflammatory infiltration, granulomas, alveolar exudate, cavitation secondary to necrosis, and fibrosis. Conclusion: Paracoccidioidomycosis can present different tomography patterns, which can involve both the interstitium and the airspace. These abnormalities can be pathologically correlated with inflammatory infiltration, granulomatous reaction, and fibrosis.

  10. Household computer and Internet access: The digital divide in a pediatric clinic population

    Science.gov (United States)

    Carroll, Aaron E.; Rivara, Frederick P.; Ebel, Beth; Zimmerman, Frederick J.; Christakis, Dimitri A.

    2005-01-01

    Past studies have noted a digital divide, or inequality in computer and Internet access related to socioeconomic class. This study sought to measure how many households in a pediatric primary care outpatient clinic had household access to computers and the Internet, and whether this access differed by socio-economic status or other demographic information. We conducted a phone survey of a population-based sample of parents with children ages 0 to 11 years old. Analyses assessed predictors of having home access to a computer, the Internet, and high-speed Internet service. Overall, 88.9% of all households owned a personal computer, and 81.4% of all households had Internet access. Among households with Internet access, 48.3% had high speed Internet at home. There were statistically significant associations between parental income or education and home computer ownership and Internet access. However, the impact of this difference was lessened by the fact that over 60% of families with annual household income of $10,000–$25,000, and nearly 70% of families with only a high-school education had Internet access at home. While income and education remain significant predictors of household computer and internet access, many patients and families at all economic levels have access, and might benefit from health promotion interventions using these modalities. PMID:16779012

  11. Computer code MLCOSP for multiple-correlation and spectrum analysis with a hybrid computer

    International Nuclear Information System (INIS)

    Oguma, Ritsuo; Fujii, Yoshio; Usui, Hozumi; Watanabe, Koichi

    1975-10-01

    Usage of the computer code MLCOSP(Multiple Correlation and Spectrum) developed is described for a hybrid computer installed in JAERI Functions of the hybrid computer and its terminal devices are utilized ingeniously in the code to reduce complexity of the data handling which occurrs in analysis of the multivariable experimental data and to perform the analysis in perspective. Features of the code are as follows; Experimental data can be fed to the digital computer through the analog part of the hybrid computer by connecting with a data recorder. The computed results are displayed in figures, and hardcopies are taken when necessary. Series-messages to the code are shown on the terminal, so man-machine communication is possible. And further the data can be put in through a keyboard, so case study according to the results of analysis is possible. (auth.)

  12. Prescription for trouble: Medicare Part D and patterns of computer and internet access among the elderly.

    Science.gov (United States)

    Wright, David W; Hill, Twyla J

    2009-01-01

    The Medicare Prescription Drug, Improvement, and Modernization Act of 2003 specifically encourages Medicare enrollees to use the Internet to obtain information regarding the new prescription drug insurance plans and to enroll in a plan. This reliance on computer technology and the Internet leads to practical questions regarding implementation of the insurance coverage. For example, it seems unlikely that all Medicare enrollees have access to computers and the Internet or that they are all computer literate. This study uses the 2003 Current Population Survey to examine the effects of disability and income on computer access and Internet use among the elderly. Internet access declines with age and is exacerbated by disabilities. Also, decreases in income lead to decreases in computer ownership and use. Therefore, providing prescription drug coverage primarily through the Internet seems likely to maintain or increase stratification of access to health care, especially for low-income, disabled elderly, who are also a group most in need of health care access.

  13. Paging memory from random access memory to backing storage in a parallel computer

    Science.gov (United States)

    Archer, Charles J; Blocksome, Michael A; Inglett, Todd A; Ratterman, Joseph D; Smith, Brian E

    2013-05-21

    Paging memory from random access memory (`RAM`) to backing storage in a parallel computer that includes a plurality of compute nodes, including: executing a data processing application on a virtual machine operating system in a virtual machine on a first compute node; providing, by a second compute node, backing storage for the contents of RAM on the first compute node; and swapping, by the virtual machine operating system in the virtual machine on the first compute node, a page of memory from RAM on the first compute node to the backing storage on the second compute node.

  14. How You Can Protect Public Access Computers "and" Their Users

    Science.gov (United States)

    Huang, Phil

    2007-01-01

    By providing the public with online computing facilities, librarians make available a world of information resources beyond their traditional print materials. Internet-connected computers in libraries greatly enhance the opportunity for patrons to enjoy the benefits of the digital age. Unfortunately, as hackers become more sophisticated and…

  15. ACCESS TO A COMPUTER SYSTEM. BETWEEN LEGAL PROVISIONS AND TECHNICAL REALITY

    Directory of Open Access Journals (Sweden)

    Maxim DOBRINOIU

    2016-05-01

    Full Text Available Nowadays, on a rise of cybersecurity incidents and a very complex IT&C environment, the national legal systems must adapt in order to properly address the new and modern forms of criminality in cyberspace. The illegal access to a computer system remains one of the most important cyber-related crimes due to its popularity but also from the perspective as being a door opened to computer data and sometimes a vehicle for other tech crimes. In the same time, the information society services slightly changed the IT paradigm and represent the new interface between users and systems. Is true that services rely on computer systems, but accessing services goes now beyond the simple accessing computer systems as commonly understood by most of the legislations. The article intends to explain other sides of the access related to computer systems and services, with the purpose to advance possible legal solutions to certain case scenarios.

  16. The Battle to Secure Our Public Access Computers

    Science.gov (United States)

    Sendze, Monique

    2006-01-01

    Securing public access workstations should be a significant part of any library's network and information-security strategy because of the sensitive information patrons enter on these workstations. As the IT manager for the Johnson County Library in Kansas City, Kan., this author is challenged to make sure that thousands of patrons get the access…

  17. 61 Gender, Computer Access and Use as Predictors of Nigerian ...

    African Journals Online (AJOL)

    Nekky Umera

    ... Awolowo University, Faculty of. Education, Department of Educational Technology, Ile-Ife, Osun-State, ... that failure to adopt computer technology in schools results in student's incompetence in ..... southside elementary school. Retrieved on ...

  18. Restricted access processor - An application of computer security technology

    Science.gov (United States)

    Mcmahon, E. M.

    1985-01-01

    This paper describes a security guard device that is currently being developed by Computer Sciences Corporation (CSC). The methods used to provide assurance that the system meets its security requirements include the system architecture, a system security evaluation, and the application of formal and informal verification techniques. The combination of state-of-the-art technology and the incorporation of new verification procedures results in a demonstration of the feasibility of computer security technology for operational applications.

  19. Neuroanatomical correlates of brain-computer interface performance.

    Science.gov (United States)

    Kasahara, Kazumi; DaSalla, Charles Sayo; Honda, Manabu; Hanakawa, Takashi

    2015-04-15

    Brain-computer interfaces (BCIs) offer a potential means to replace or restore lost motor function. However, BCI performance varies considerably between users, the reasons for which are poorly understood. Here we investigated the relationship between sensorimotor rhythm (SMR)-based BCI performance and brain structure. Participants were instructed to control a computer cursor using right- and left-hand motor imagery, which primarily modulated their left- and right-hemispheric SMR powers, respectively. Although most participants were able to control the BCI with success rates significantly above chance level even at the first encounter, they also showed substantial inter-individual variability in BCI success rate. Participants also underwent T1-weighted three-dimensional structural magnetic resonance imaging (MRI). The MRI data were subjected to voxel-based morphometry using BCI success rate as an independent variable. We found that BCI performance correlated with gray matter volume of the supplementary motor area, supplementary somatosensory area, and dorsal premotor cortex. We suggest that SMR-based BCI performance is associated with development of non-primary somatosensory and motor areas. Advancing our understanding of BCI performance in relation to its neuroanatomical correlates may lead to better customization of BCIs based on individual brain structure. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Negative correlates of computer game play in adolescents.

    Science.gov (United States)

    Colwell, J; Payne, J

    2000-08-01

    There is some concern that playing computer games may be associated with social isolation, lowered self-esteem, and aggression among adolescents. Measures of these variables were included in a questionnaire completed by 204 year eight students at a North London comprehensive school. Principal components analysis of a scale to assess needs fulfilled by game play provided some support for the notion of 'electronic friendship' among boys, but there was no evidence that game play leads to social isolation. Play was not linked to self-esteem in girls, but a negative relationship was obtained between self-esteem and frequency of play in boys. However, self-esteem was not associated with total exposure to game play. Aggression scores were not related to the number of games with aggressive content named among three favourite games, but they were positively correlated with total exposure to game play. A multiple regression analysis revealed that sex and total game play exposure each accounted for a significant but small amount of the variance in aggression scores. The positive correlation between playing computer games and aggression provides some justification for further investigation of the causal hypothesis, and possible methodologies are discussed.

  1. Computer and internet access for long-term care residents: perceived benefits and barriers.

    Science.gov (United States)

    Tak, Sunghee H; Beck, Cornelia; McMahon, Ed

    2007-05-01

    In this study, the authors examined residents' computer and Internet access, as well as benefits and barriers to access in nursing homes. Administrators of 64 nursing homes in a national chain completed surveys. Fourteen percent of the nursing homes provided computers for residents to use, and 11% had Internet access. Some residents owned personal computers in their rooms. Administrators perceived the benefits of computer and Internet use for residents as facilitating direct communication with family and providing mental exercise, education, and enjoyment. Perceived barriers included cost and space for computer equipment and residents' cognitive and physical impairments. Implications of residents' computer activities were discussed for nursing care. Further research is warranted to examine therapeutic effects of computerized activities and their cost effectiveness.

  2. Student Perceived Importance and Correlations of Selected Computer Literacy Course Topics

    Science.gov (United States)

    Ciampa, Mark

    2013-01-01

    Traditional college-level courses designed to teach computer literacy are in a state of flux. Today's students have high rates of access to computing technology and computer ownership, leading many policy decision makers to conclude that students already are computer literate and thus computer literacy courses are dinosaurs in a modern digital…

  3. Lifelong mobile learning: Increasing accessibility and flexibility with tablet computers and ebooks

    OpenAIRE

    Kalz, Marco

    2011-01-01

    Kalz, M. (2011, 1 September). Lifelong mobile learning: Increasing accessibility and flexibility with tablet computers and ebooks. Presentation provided during the opening ceremony of the iPad pilot for schakelzone rechten, Utrecht, The Netherlands.

  4. Youth with cerebral palsy with differing upper limb abilities: how do they access computers?

    Science.gov (United States)

    Davies, T Claire; Chau, Tom; Fehlings, Darcy L; Ameratunga, Shanthi; Stott, N Susan

    2010-12-01

    To identify the current level of awareness of different computer access technologies and the choices made regarding mode of access by youth with cerebral palsy (CP) and their families. Survey. Two tertiary-level rehabilitation centers in New Zealand and Canada. Youth (N=60) with CP, Manual Ability Classification Scale (MACS) levels I to V, age 13 to 25 years. Not applicable. Questionnaire. Fifty (83%) of the 60 youth were aware of at least 1 available assistive technology (AT), such as touch screens and joysticks. However, only 34 youth (57%) were familiar with the accessibility options currently available in the most common operating systems. Thirty-three (94%) of 35 youth who were MACS I and II used a standard mouse and keyboard, while few chose to use assistive technology or accessibility options. In contrast, 10 (40%) of 25 youth who were MACS III to V used a variety of assistive technologies such as touch screens, joysticks, trackballs, and scanning technologies. This group also had the highest use of accessibility options, although only 15 (60%) of the 25 were aware of them. Most youth with CP were aware of, and used, assistive technologies to enhance their computer access but were less knowledgeable about accessibility options. Accessibility options allow users to modify their own computer interface and can thus enhance computer access for youth with CP. Clinicians should be knowledgeable enough to give informed advice in this area of computer access, thus ensuring that all youth with CP can benefit from both AT and accessibility options, as required. Copyright © 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Impact of the Digital Divide on Computer Use and Internet Access on the Poor in Nigeria

    Science.gov (United States)

    Tayo, Omolara; Thompson, Randall; Thompson, Elizabeth

    2016-01-01

    We recruited 20 community members in Ido Local Government Area, Oyo state and Yewa Local Government Area, Ogun state in Nigeria to explore experiences and perceptions of Internet access and computer use. Face-to-face interviews were conducted using open-ended questions to collect qualitative data regarding accessibility of information and…

  6. Change in Computer Access and the Academic Achievement of Immigrant Children

    Science.gov (United States)

    Moon, Ui Jeong; Hofferth, Sandra

    2018-01-01

    Background/Context: Increased interest in the correlates of media devices available to children has led to research indicating that access to and use of technology are positively associated with children's academic achievement. However, the digital divide remains; not all children have access to digital technologies, and not all children can…

  7. Malignant pleural mesothelioma: Computed tomography and correlation with histology

    Energy Technology Data Exchange (ETDEWEB)

    Seely, Jean M. [Department of Diagnostic Imaging, Ottawa Hospital, 1053 Carling Avenue, Ottawa, Ontario K1Y 4E9 (Canada)], E-mail: jeseely@ottawahospital.on.ca; Nguyen, Elsie T., E-mail: nguyen_elsie@hotmail.com; Churg, Andrew M. [University of British Columbia, 2211 Wesbrook Mall, Vancouver, BC V6T 1W5 (Canada)], E-mail: achurg@interchange.ubc.ca; Mueller, Nestor L. [University of British Columbia, Vancouver Hospital and Health Sciences Centre, 855 West 12th Avenue, Vancouver, BC V5Z 1M9 (Canada)], E-mail: nmuller@vanhosp.bc.ca

    2009-06-15

    Objective: To review the computed tomography (CT) imaging findings of pleural mesothelioma at presentation and to correlate the CT with the histological subtype. Materials and methods: Pathology reports from 1997 to 2006 were reviewed at two academic institutions to identify patients with proven pleural mesothelioma. Diagnosis was based on histologic findings in specimens obtained by transthoracic needle biopsy, surgical biopsy or resection. All histology slides were reviewed by a lung pathologist. CT scans, available in 92 patients, were reviewed blindly and in random order by two independent radiologists. Kappa analysis was completed to assess inter-observer agreement. Eighty patients in whom there was no significant delay between CT imaging and histological diagnosis were assessed by logistic regression analysis to correlate CT and histologic findings. Results: Seventy-two of the 92 mesotheliomas were epithelial, 15 sarcomatous, and 5 of mixed histology. All patients (77 male, 15 female, mean age 68 years) had pleural thickening on CT; the thickening was nodular in 79 patients (86%) and mediastinal in 87 (95%). Ipsilateral volume loss was seen in 42 patients (46%). Pleural effusions were present in 80 patients (87%), being large (>2/3 hemithorax) in 19 patients (21%). Atypical features at presentation included bilateral disease in three patients (3%), and spontaneous pneumothoraces in nine patients (10%). Internal mammary lymphadenopathy was observed in 48 patients (52%) and cardiophrenic lymphadenopathy in 42 (46%). Inter-observer agreement was excellent (average kappa = 0.89). Ipsilateral volume loss was associated with sarcomatous or mixed mesothelioma (p = 0.004). Using logistic regression analysis, other CT findings did not correlate with histological subtype. Conclusions: Ipsilateral volume loss is most frequently associated with sarcomatous or mixed mesothelioma. The remaining imaging findings are not helpful in predicting the histological subtype of

  8. Malignant pleural mesothelioma: Computed tomography and correlation with histology

    International Nuclear Information System (INIS)

    Seely, Jean M.; Nguyen, Elsie T.; Churg, Andrew M.; Mueller, Nestor L.

    2009-01-01

    Objective: To review the computed tomography (CT) imaging findings of pleural mesothelioma at presentation and to correlate the CT with the histological subtype. Materials and methods: Pathology reports from 1997 to 2006 were reviewed at two academic institutions to identify patients with proven pleural mesothelioma. Diagnosis was based on histologic findings in specimens obtained by transthoracic needle biopsy, surgical biopsy or resection. All histology slides were reviewed by a lung pathologist. CT scans, available in 92 patients, were reviewed blindly and in random order by two independent radiologists. Kappa analysis was completed to assess inter-observer agreement. Eighty patients in whom there was no significant delay between CT imaging and histological diagnosis were assessed by logistic regression analysis to correlate CT and histologic findings. Results: Seventy-two of the 92 mesotheliomas were epithelial, 15 sarcomatous, and 5 of mixed histology. All patients (77 male, 15 female, mean age 68 years) had pleural thickening on CT; the thickening was nodular in 79 patients (86%) and mediastinal in 87 (95%). Ipsilateral volume loss was seen in 42 patients (46%). Pleural effusions were present in 80 patients (87%), being large (>2/3 hemithorax) in 19 patients (21%). Atypical features at presentation included bilateral disease in three patients (3%), and spontaneous pneumothoraces in nine patients (10%). Internal mammary lymphadenopathy was observed in 48 patients (52%) and cardiophrenic lymphadenopathy in 42 (46%). Inter-observer agreement was excellent (average kappa = 0.89). Ipsilateral volume loss was associated with sarcomatous or mixed mesothelioma (p = 0.004). Using logistic regression analysis, other CT findings did not correlate with histological subtype. Conclusions: Ipsilateral volume loss is most frequently associated with sarcomatous or mixed mesothelioma. The remaining imaging findings are not helpful in predicting the histological subtype of

  9. “Future Directions”: m-government computer systems accessed via cloud computing – advantages and possible implementations

    OpenAIRE

    Daniela LIŢAN

    2015-01-01

    In recent years, the activities of companies and Public Administration had been automated and adapted to the current information system. Therefore, in this paper, I will present and exemplify the benefits of m-government computer systems development and implementation (which can be accessed from mobile devices and which are specific to the workflow of Public Administrations) starting from the “experience” of e-government systems implementation in the context of their access and usage through ...

  10. Preserving access to ALEPH computing environment via virtual machines

    International Nuclear Information System (INIS)

    Coscetti, Simone; Boccali, Tommaso; Arezzini, Silvia; Maggi, Marcello

    2014-01-01

    The ALEPH Collaboration [1] took data at the LEP (CERN) electron-positron collider in the period 1989-2000, producing more than 300 scientific papers. While most of the Collaboration activities stopped in the last years, the data collected still has physics potential, with new theoretical models emerging, which ask checks with data at the Z and WW production energies. An attempt to revive and preserve the ALEPH Computing Environment is presented; the aim is not only the preservation of the data files (usually called bit preservation), but of the full environment a physicist would need to perform brand new analyses. Technically, a Virtual Machine approach has been chosen, using the VirtualBox platform. Concerning simulated events, the full chain from event generators to physics plots is possible, and reprocessing of data events is also functioning. Interactive tools like the DALI event display can be used on both data and simulated events. The Virtual Machine approach is suited for both interactive usage, and for massive computing using Cloud like approaches.

  11. Gender Differences in Availability, Internet Access and Rate of Usage of Computers among Distance Education Learners.

    Science.gov (United States)

    Atan, Hanafi; Sulaiman, Fauziah; Rahman, Zuraidah Abd; Idrus, Rozhan Mohammed

    2002-01-01

    Explores the level of availability of computers, Internet accessibility, and the rate of usage of computers both at home and at the workplace between distance education learners according to gender. Results of questionnaires completed at the Universiti Sains Malaysia indicate that distance education reduces the gender gap. (Author/LRW)

  12. The ENSDF radioactivity data base for IBM-PC and computer network access

    International Nuclear Information System (INIS)

    Ekstroem, P.; Spanier, L.

    1989-08-01

    A data base system for radioactivity gamma rays is described. A base with approximately 15000 gamma rays from 2777 decays is available for installation on the hard disk of a PC, and a complete system with approximately 73000 gamma rays is available for on-line access via the NORDic University computer NETwork (NORDUNET) and the Swedish University computer NETwork (SUNET)

  13. Do Your School Policies Provide Equal Access to Computers? Are You Sure?

    Science.gov (United States)

    DuBois, Phyllis A.; Schubert, Jane G.

    1986-01-01

    Outlines how school policies can unintentionally perpetuate gender discrimination in student computer use and access. Describes four areas of administrative policies that can cause inequities and provides ways for administrators to counteract these policies. Includes discussion of a program to balance computer use, and an abstract of an article…

  14. Efficient Reduction of Access Latency through Object Correlations in Virtual Environments

    Directory of Open Access Journals (Sweden)

    Damon Shing-Min Liu

    2007-01-01

    Full Text Available Object correlations are common semantic patterns in virtual environments. They can be exploited to improve the effectiveness of storage caching, prefetching, data layout, and disk scheduling. However, we have little approaches for discovering object correlations in VE to improve the performance of storage systems. Being an interactive feedback-driven paradigm, it is critical that the user receives responses to his navigation requests with little or no time lag. Therefore, we propose a class of view-based projection-generation method for mining various frequent sequential traversal patterns in the virtual environments. The frequent sequential traversal patterns are used to predict the user navigation behavior and, through clustering scheme, help to reduce disk access time with proper patterns placement into disk blocks. Finally, the effectiveness of these schemes is shown through simulation to demonstrate how these proposed techniques not only significantly cut down disk access time, but also enhance the accuracy of data prefetching.

  15. Task-and-role-based access-control model for computational grid

    Institute of Scientific and Technical Information of China (English)

    LONG Tao; HONG Fan; WU Chi; SUN Ling-li

    2007-01-01

    Access control in a grid environment is a challenging issue because the heterogeneous nature and independent administration of geographically dispersed resources in grid require access control to use fine-grained policies. We established a task-and-role-based access-control model for computational grid (CG-TRBAC model), integrating the concepts of role-based access control (RBAC) and task-based access control (TBAC). In this model, condition restrictions are defined and concepts specifically tailored to Workflow Management System are simplified or omitted so that role assignment and security administration fit computational grid better than traditional models; permissions are mutable with the task status and system variables, and can be dynamically controlled. The CG-TRBAC model is proved flexible and extendible. It can implement different control policies. It embodies the security principle of least privilege and executes active dynamic authorization. A task attribute can be extended to satisfy different requirements in a real grid system.

  16. A Secure and Verifiable Outsourced Access Control Scheme in Fog-Cloud Computing.

    Science.gov (United States)

    Fan, Kai; Wang, Junxiong; Wang, Xin; Li, Hui; Yang, Yintang

    2017-07-24

    With the rapid development of big data and Internet of things (IOT), the number of networking devices and data volume are increasing dramatically. Fog computing, which extends cloud computing to the edge of the network can effectively solve the bottleneck problems of data transmission and data storage. However, security and privacy challenges are also arising in the fog-cloud computing environment. Ciphertext-policy attribute-based encryption (CP-ABE) can be adopted to realize data access control in fog-cloud computing systems. In this paper, we propose a verifiable outsourced multi-authority access control scheme, named VO-MAACS. In our construction, most encryption and decryption computations are outsourced to fog devices and the computation results can be verified by using our verification method. Meanwhile, to address the revocation issue, we design an efficient user and attribute revocation method for it. Finally, analysis and simulation results show that our scheme is both secure and highly efficient.

  17. A Secure and Verifiable Outsourced Access Control Scheme in Fog-Cloud Computing

    Science.gov (United States)

    Fan, Kai; Wang, Junxiong; Wang, Xin; Li, Hui; Yang, Yintang

    2017-01-01

    With the rapid development of big data and Internet of things (IOT), the number of networking devices and data volume are increasing dramatically. Fog computing, which extends cloud computing to the edge of the network can effectively solve the bottleneck problems of data transmission and data storage. However, security and privacy challenges are also arising in the fog-cloud computing environment. Ciphertext-policy attribute-based encryption (CP-ABE) can be adopted to realize data access control in fog-cloud computing systems. In this paper, we propose a verifiable outsourced multi-authority access control scheme, named VO-MAACS. In our construction, most encryption and decryption computations are outsourced to fog devices and the computation results can be verified by using our verification method. Meanwhile, to address the revocation issue, we design an efficient user and attribute revocation method for it. Finally, analysis and simulation results show that our scheme is both secure and highly efficient. PMID:28737733

  18. NCI Workshop Report: Clinical and Computational Requirements for Correlating Imaging Phenotypes with Genomics Signatures

    Directory of Open Access Journals (Sweden)

    Rivka Colen

    2014-10-01

    Full Text Available The National Cancer Institute (NCI Cancer Imaging Program organized two related workshops on June 26–27, 2013, entitled “Correlating Imaging Phenotypes with Genomics Signatures Research” and “Scalable Computational Resources as Required for Imaging-Genomics Decision Support Systems.” The first workshop focused on clinical and scientific requirements, exploring our knowledge of phenotypic characteristics of cancer biological properties to determine whether the field is sufficiently advanced to correlate with imaging phenotypes that underpin genomics and clinical outcomes, and exploring new scientific methods to extract phenotypic features from medical images and relate them to genomics analyses. The second workshop focused on computational methods that explore informatics and computational requirements to extract phenotypic features from medical images and relate them to genomics analyses and improve the accessibility and speed of dissemination of existing NIH resources. These workshops linked clinical and scientific requirements of currently known phenotypic and genotypic cancer biology characteristics with imaging phenotypes that underpin genomics and clinical outcomes. The group generated a set of recommendations to NCI leadership and the research community that encourage and support development of the emerging radiogenomics research field to address short-and longer-term goals in cancer research.

  19. Prospective evaluation of an internet-linked handheld computer critical care knowledge access system.

    Science.gov (United States)

    Lapinsky, Stephen E; Wax, Randy; Showalter, Randy; Martinez-Motta, J Carlos; Hallett, David; Mehta, Sangeeta; Burry, Lisa; Stewart, Thomas E

    2004-12-01

    Critical care physicians may benefit from immediate access to medical reference material. We evaluated the feasibility and potential benefits of a handheld computer based knowledge access system linking a central academic intensive care unit (ICU) to multiple community-based ICUs. Four community hospital ICUs with 17 physicians participated in this prospective interventional study. Following training in the use of an internet-linked, updateable handheld computer knowledge access system, the physicians used the handheld devices in their clinical environment for a 12-month intervention period. Feasibility of the system was evaluated by tracking use of the handheld computer and by conducting surveys and focus group discussions. Before and after the intervention period, participants underwent simulated patient care scenarios designed to evaluate the information sources they accessed, as well as the speed and quality of their decision making. Participants generated admission orders during each scenario, which were scored by blinded evaluators. Ten physicians (59%) used the system regularly, predominantly for nonmedical applications (median 32.8/month, interquartile range [IQR] 28.3-126.8), with medical software accessed less often (median 9/month, IQR 3.7-13.7). Eight out of 13 physicians (62%) who completed the final scenarios chose to use the handheld computer for information access. The median time to access information on the handheld handheld computer was 19 s (IQR 15-40 s). This group exhibited a significant improvement in admission order score as compared with those who used other resources (P = 0.018). Benefits and barriers to use of this technology were identified. An updateable handheld computer system is feasible as a means of point-of-care access to medical reference material and may improve clinical decision making. However, during the study, acceptance of the system was variable. Improved training and new technology may overcome some of the barriers we

  20. Liver tumors, correlation of computed tomography (CT) and pathology

    Energy Technology Data Exchange (ETDEWEB)

    Okazaki, Atsushi; Niibe, Hideo; Mitsuhashi, Norio

    1984-09-01

    Computed tomographic and pathologic correlation was studied in 12 autopsied cases with 11 cases of metastatic liver tumors and 1 case of hepatocellular carcinoma. Despite of proliferative patterns of the tumors, nodular low attenuations on CT showed scattered nodular lesions and geographic low attenuations on CT showed groups of multiple small nodular lesions, macroscopically. Abnormal areas of low attenuation were generally diminished by drip infusion contrast enhancement, which was more significant on tumors of infiltrative proliferation. Tumors of infiltrative proliferation revealed little degeneration of surrounding liver cells and abnormal areas of low attenuation were more distinct before contrast enhancement. Tumors of expansive proliferation revealed obvious degeneration of surrounding liver cells and a case having about 200 layers of degenerated liver cells revealed more distinct after contrast enhancement. The central lower density areas in abnormal areas of low attenuation on CT coincided with liquefactive necroses with scanty capillary. vessels and fibrotic changes, histopathologically. But coagulative necroses without decrease of surrouding blood flows were not visualized on CT. CT could not demonstrate the liquefactive necroses in more small nodules than 2 cm in diameter. (J.P.N.).

  1. No Special Equipment Required: The Accessibility Features Built into the Windows and Macintosh Operating Systems make Computers Accessible for Students with Special Needs

    Science.gov (United States)

    Kimball,Walter H.; Cohen,Libby G.; Dimmick,Deb; Mills,Rick

    2003-01-01

    The proliferation of computers and other electronic learning devices has made knowledge and communication accessible to people with a wide range of abilities. Both Windows and Macintosh computers have accessibility options to help with many different special needs. This documents discusses solutions for: (1) visual impairments; (2) hearing…

  2. Remote data access in computational jobs on the ATLAS data grid

    CERN Document Server

    Begy, Volodimir; The ATLAS collaboration; Lassnig, Mario

    2018-01-01

    This work describes the technique of remote data access from computational jobs on the ATLAS data grid. In comparison to traditional data movement and stage-in approaches it is well suited for data transfers which are asynchronous with respect to the job execution. Hence, it can be used for optimization of data access patterns based on various policies. In this study, remote data access is realized with the HTTP and WebDAV protocols, and is investigated in the context of intra- and inter-computing site data transfers. In both cases, the typical scenarios for application of remote data access are identified. The paper also presents an analysis of parameters influencing the data goodput between heterogeneous storage element - worker node pairs on the grid.

  3. Computer access and Internet use by urban and suburban emergency department customers.

    Science.gov (United States)

    Bond, Michael C; Klemt, Ryan; Merlis, Jennifer; Kopinski, Judith E; Hirshon, Jon Mark

    2012-07-01

    Patients are increasingly using the Internet (43% in 2000 vs. 70% in 2006) to obtain health information, but is there a difference in the ability of urban and suburban emergency department (ED) customers to access the Internet? To assess computer and Internet resources available to and used by people waiting to be seen in an urban ED and a suburban ED. Individuals waiting in the ED were asked survey questions covering demographics, type of insurance, access to a primary care provider, reason for their ED visit, computer access, and ability to access the Internet for health-related matters. There were 304 individuals who participated, 185 in the urban ED and 119 in the suburban ED. Urban subjects were more likely than suburban to be women, black, have low household income, and were less likely to have insurance. The groups were similar in regard to average age, education, and having a primary care physician. Suburban respondents were more likely to own a computer, but the majority in both groups had access to computers and the Internet. Their frequency of accessing the Internet was similar, as were their reasons for using it. Individuals from the urban ED were less willing to schedule appointments via the Internet but more willing to contact their health care provider via e-mail. The groups were equally willing to use the Internet to fill prescriptions and view laboratory results. Urban and suburban ED customers had similar access to the Internet. Both groups were willing to use the Internet to access personal health information. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Fingerprint authentication via joint transform correlator and its application in remote access control of a 3D microscopic system

    Science.gov (United States)

    He, Wenqi; Lai, Hongji; Wang, Meng; Liu, Zeyi; Yin, Yongkai; Peng, Xiang

    2014-05-01

    We present a fingerprint authentication scheme based on the optical joint transform correlator (JTC) and further describe its application to the remote access control of a Network-based Remote Laboratory (NRL). It is built to share a 3D microscopy system of our realistic laboratory in Shenzhen University with the remote co-researchers in Stuttgart University. In this article, we would like to focus on the involved security issues, mainly on the verification of various remote visitors to our NRL. By making use of the JTC-based optical pattern recognition technique as well as the Personal Identification Number (PIN), we are able to achieve the aim of authentication and access control for any remote visitors. Note that only the authorized remote visitors could be guided to the Virtual Network Computer (VNC), a cross-platform software, which allows the remote visitor to access the desktop applications and visually manipulate the instruments of our NRL through the internet. Specifically to say, when a remote visitor attempts to access to our NRL, a PIN is mandatory required in advance, which is followed by fingerprint capturing and verification. Only if both the PIN and the fingerprint are correct, can one be regarded as an authorized visitor, and then he/she would get the authority to visit our NRL by the VNC. It is also worth noting that the aforementioned "two-step verification" strategy could be further applied to verify the identity levels of various remote visitors, and therefore realize the purpose of diversified visitor management.

  5. A National Study of the Relationship between Home Access to a Computer and Academic Performance Scores of Grade 12 U.S. Science Students: An Analysis of the 2009 NAEP Data

    Science.gov (United States)

    Coffman, Mitchell Ward

    The purpose of this dissertation was to examine the relationship between student access to a computer at home and academic achievement. The 2009 National Assessment of Educational Progress (NAEP) dataset was probed using the National Data Explorer (NDE) to investigate correlations in the subsets of SES, Parental Education, Race, and Gender as it relates to access of a home computer and improved performance scores for U.S. public school grade 12 science students. A causal-comparative approach was employed seeking clarity on the relationship between home access and performance scores. The influence of home access cannot overcome the challenges students of lower SES face. The achievement gap, or a second digital divide, for underprivileged classes of students, including minorities does not appear to contract via student access to a home computer. Nonetheless, in tests for significance, statistically significant improvement in science performance scores was reported for those having access to a computer at home compared to those not having access. Additionally, regression models reported evidence of correlations between and among subsets of controls for the demographic factors gender, race, and socioeconomic status. Variability in these correlations was high; suggesting influence from unobserved factors may have more impact upon the dependent variable. Having access to a computer at home increases performance scores for grade 12 general science students of all races, genders and socioeconomic levels. However, the performance gap is roughly equivalent to the existing performance gap of the national average for science scores, suggesting little influence from access to a computer on academic achievement. The variability of scores reported in the regression analysis models reflects a moderate to low effect, suggesting an absence of causation. These statistical results are accurate and confirm the literature review, whereby having access to a computer at home and the

  6. DELTA - a computer program to analyze gamma-gamma angular correlations from unaligned states

    International Nuclear Information System (INIS)

    Ekstroem, L.P.

    1983-10-01

    A computer program to analyze gamma-gamma angular correlations from radioactive decay and from thermal-neutron capture is described. The program can, in addition to correlation data, handle mixing ratio and conversion coefficient data. (author)

  7. Access to and use of computers among clinical dental students of ...

    African Journals Online (AJOL)

    Access to and use of computers among clinical dental students of the University of Lagos. PO Ayanbadejo, OO Sofola, OG Uti. Abstract. No Abstract. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Article Metrics. No metrics found. Metrics powered by PLOS ALM

  8. Alexia without agraphia: Clinical-computed tomographic correlations

    International Nuclear Information System (INIS)

    Weisberg, L.A.; Wall, M.; Charity Hospital, New Orleans, LA; Veterans Administration Hospital, New Orleans, LA

    1987-01-01

    Four patients with alexia without agraphia had CT lesions which correlated with the clinical findings. All lesions were vascular; two were spontaneous intracerebral hematomas and two were ischemic infarctions in the posterior cerebral artery distribution. The lesions were located in the posterior portion of the dominant hemisphere. The location of the lesion correlated with the presence or absence of visual field abnormalities. (orig.)

  9. Spin-transfer torque magnetoresistive random-access memory technologies for normally off computing (invited)

    International Nuclear Information System (INIS)

    Ando, K.; Yuasa, S.; Fujita, S.; Ito, J.; Yoda, H.; Suzuki, Y.; Nakatani, Y.; Miyazaki, T.

    2014-01-01

    Most parts of present computer systems are made of volatile devices, and the power to supply them to avoid information loss causes huge energy losses. We can eliminate this meaningless energy loss by utilizing the non-volatile function of advanced spin-transfer torque magnetoresistive random-access memory (STT-MRAM) technology and create a new type of computer, i.e., normally off computers. Critical tasks to achieve normally off computers are implementations of STT-MRAM technologies in the main memory and low-level cache memories. STT-MRAM technology for applications to the main memory has been successfully developed by using perpendicular STT-MRAMs, and faster STT-MRAM technologies for applications to the cache memory are now being developed. The present status of STT-MRAMs and challenges that remain for normally off computers are discussed

  10. SmartVeh: Secure and Efficient Message Access Control and Authentication for Vehicular Cloud Computing.

    Science.gov (United States)

    Huang, Qinlong; Yang, Yixian; Shi, Yuxiang

    2018-02-24

    With the growing number of vehicles and popularity of various services in vehicular cloud computing (VCC), message exchanging among vehicles under traffic conditions and in emergency situations is one of the most pressing demands, and has attracted significant attention. However, it is an important challenge to authenticate the legitimate sources of broadcast messages and achieve fine-grained message access control. In this work, we propose SmartVeh, a secure and efficient message access control and authentication scheme in VCC. A hierarchical, attribute-based encryption technique is utilized to achieve fine-grained and flexible message sharing, which ensures that vehicles whose persistent or dynamic attributes satisfy the access policies can access the broadcast message with equipped on-board units (OBUs). Message authentication is enforced by integrating an attribute-based signature, which achieves message authentication and maintains the anonymity of the vehicles. In order to reduce the computations of the OBUs in the vehicles, we outsource the heavy computations of encryption, decryption and signing to a cloud server and road-side units. The theoretical analysis and simulation results reveal that our secure and efficient scheme is suitable for VCC.

  11. Evaluation of External Memory Access Performance on a High-End FPGA Hybrid Computer

    Directory of Open Access Journals (Sweden)

    Konstantinos Kalaitzis

    2016-10-01

    Full Text Available The motivation of this research was to evaluate the main memory performance of a hybrid super computer such as the Convey HC-x, and ascertain how the controller performs in several access scenarios, vis-à-vis hand-coded memory prefetches. Such memory patterns are very useful in stencil computations. The theoretical bandwidth of the memory of the Convey is compared with the results of our measurements. The accurate study of the memory subsystem is particularly useful for users when they are developing their application-specific personality. Experiments were performed to measure the bandwidth between the coprocessor and the memory subsystem. The experiments aimed mainly at measuring the reading access speed of the memory from Application Engines (FPGAs. Different ways of accessing data were used in order to find the most efficient way to access memory. This way was proposed for future work in the Convey HC-x. When performing a series of accesses to memory, non-uniform latencies occur. The Memory Controller of the Convey HC-x in the coprocessor attempts to cover this latency. We measure memory efficiency as a ratio of the number of memory accesses and the number of execution cycles. The result of this measurement converges to one in most cases. In addition, we performed experiments with hand-coded memory accesses. The analysis of the experimental results shows how the memory subsystem and Memory Controllers work. From this work we conclude that the memory controllers do an excellent job, largely because (transparently to the user they seem to cache large amounts of data, and hence hand-coding is not needed in most situations.

  12. Crohn’s disease Activity: Abdominal Computed Tomography Histopathology Correlation

    Directory of Open Access Journals (Sweden)

    N. Paquet

    2016-01-01

    Conclusion: CT-based biomarkers including wall thickness, mesenteric fat stranding, mesenteric lymphadenopathy and mesenteric abscess positively correlated with the histological inflammatory activity score and therefore provided additional information for therapy stratification in symptomatic patients with CD, particularly as most of these biomarkers are hidden from endoscopy.

  13. Computed tomography in cases of coccidioidal meningitis, with clinical correlation

    International Nuclear Information System (INIS)

    Shetter, A.G.; Fischer, D.W.; Flom, R.A.

    1985-01-01

    Cranial computed tomographic (CT) scans of 22 patients with coccidioidal meningitis were reviewed and their clinical course was analyzed. Abnormalities of the ventricular system or the basilar cisterns or both were present in 16 instances. Although it is not a definitive diagnostic tool, the CT scan is helpful in suggesting a diagnosis of coccidioidal meningitis and in predicting the prognosis of patients affected by the disease. 19 references, 4 figures, 2 tables

  14. Accessibility

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis

    2017-01-01

    This contribution is timely as it addresses accessibility in regards system hardware and software aligned with introduction of the Twenty-First Century Communications and Video Accessibility Act (CVAA) and adjoined game industry waiver that comes into force January 2017. This is an act created...... by the USA Federal Communications Commission (FCC) to increase the access of persons with disabilities to modern communications, and for other purposes. The act impacts advanced communications services and products including text messaging; e-mail; instant messaging; video communications; browsers; game...... platforms; and games software. However, the CVAA has no legal status in the EU. This text succinctly introduces and questions implications, impact, and wider adoption. By presenting the full CVAA and game industry waiver the text targets to motivate discussions and further publications on the subject...

  15. The NILE system architecture: fault-tolerant, wide-area access to computing and data resources

    International Nuclear Information System (INIS)

    Ricciardi, Aleta; Ogg, Michael; Rothfus, Eric

    1996-01-01

    NILE is a multi-disciplinary project building a distributed computing environment for HEP. It provides wide-area, fault-tolerant, integrated access to processing and data resources for collaborators of the CLEO experiment, though the goals and principles are applicable to many domains. NILE has three main objectives: a realistic distributed system architecture design, the design of a robust data model, and a Fast-Track implementation providing a prototype design environment which will also be used by CLEO physicists. This paper focuses on the software and wide-area system architecture design and the computing issues involved in making NILE services highly-available. (author)

  16. Using speech recognition to enhance the Tongue Drive System functionality in computer access.

    Science.gov (United States)

    Huo, Xueliang; Ghovanloo, Maysam

    2011-01-01

    Tongue Drive System (TDS) is a wireless tongue operated assistive technology (AT), which can enable people with severe physical disabilities to access computers and drive powered wheelchairs using their volitional tongue movements. TDS offers six discrete commands, simultaneously available to the users, for pointing and typing as a substitute for mouse and keyboard in computer access, respectively. To enhance the TDS performance in typing, we have added a microphone, an audio codec, and a wireless audio link to its readily available 3-axial magnetic sensor array, and combined it with a commercially available speech recognition software, the Dragon Naturally Speaking, which is regarded as one of the most efficient ways for text entry. Our preliminary evaluations indicate that the combined TDS and speech recognition technologies can provide end users with significantly higher performance than using each technology alone, particularly in completing tasks that require both pointing and text entry, such as web surfing.

  17. Computed tomographic spectrum of intracranial mycosis: correlation with histopathology

    International Nuclear Information System (INIS)

    Whelan, M.A.; Stern, J.; deNapoli, R.A.

    1981-01-01

    Four cases of intracerebral fungal infection are reviewed. The clinical course is outlined, and the computed tomographic (CT) characteristics are analyzed in light of known pathological data. The CT appearance of intracranial mycosis is dependent on the type of fungus as well as the dominant infecting form, i.e., yeast or hyphae. The hyphal form leads predominantly to a CT pattern consistent with vascular occlusion and secondary abscess formation; the yeast form generally results in noncaseating granulomas, which appear on CT scan as nodular enhancing lesions. If the patient survives the acute infective process, these fungal lesions undergo a prolonged subacute phase, and may eventually calcify

  18. Correlation between crystallographic computing and artificial intelligence research

    Energy Technology Data Exchange (ETDEWEB)

    Feigenbaum, E A [Stanford Univ., CA; Engelmore, R S; Johnson, C K

    1977-01-01

    Artificial intelligence research, as a part of computer science, has produced a variety of programs of experimental and applications interest: programs for scientific inference, chemical synthesis, planning robot control, extraction of meaning from English sentences, speech understanding, interpretation of visual images, and so on. The symbolic manipulation techniques used in artificial intelligence provide a framework for analyzing and coding the knowledge base of a problem independently of an algorithmic implementation. A possible application of artificial intelligence methodology to protein crystallography is described. 2 figures, 2 tables.

  19. Ultrasonographic study of the omentum: correlation with computed tomography

    International Nuclear Information System (INIS)

    Gallego, C.; Marin, C.; Manjon, P.; Gallego, M.S.

    1998-01-01

    While it is known that the utility of ultrasound is not restricted to the analysis of solid organs, the examination of the different structures that may be involved in abdominal pathology can add to the radiological findings and aid in therapeutic decision making. The purpose of this report is to assess the normal and abnormal sonographic aspects of the greater omentum. We studied the ultrasound images in two healthy in vitro specimens, in 30 patients with normal omentum in the presence and absence of ascites and in 13 patients in whom omental involvement was confirmed by surgical biopsy and/or fine-needle aspiration biopsy. The omentum is an elongated aperistaltic fold situated between the abdominal wall and the small bowel. Under normal conditions, it presents homogeneous echogenicity and thickness. When it is involved in a disease process, nodular, omental caking or infiltrative patterns are observed. Knowledge of the sonographic features of the omentum aids in the evaluation of the abdomen and, given its accessibility, ultrasound-guided biopsy can be carried out in those 4 cases in which it is considered necessary. (Author) 6 refs

  20. TimeSet: A computer program that accesses five atomic time services on two continents

    Science.gov (United States)

    Petrakis, P. L.

    1993-01-01

    TimeSet is a shareware program for accessing digital time services by telephone. At its initial release, it was capable of capturing time signals only from the U.S. Naval Observatory to set a computer's clock. Later the ability to synchronize with the National Institute of Standards and Technology was added. Now, in Version 7.10, TimeSet is able to access three additional telephone time services in Europe - in Sweden, Austria, and Italy - making a total of five official services addressable by the program. A companion program, TimeGen, allows yet another source of telephone time data strings for callers equipped with TimeSet version 7.10. TimeGen synthesizes UTC time data strings in the Naval Observatory's format from an accurately set and maintained DOS computer clock, and transmits them to callers. This allows an unlimited number of 'freelance' time generating stations to be created. Timesetting from TimeGen is made feasible by the advent of Becker's RighTime, a shareware program that learns the drift characteristics of a computer's clock and continuously applies a correction to keep it accurate, and also brings .01 second resolution to the DOS clock. With clock regulation by RighTime and periodic update calls by the TimeGen station to an official time source via TimeSet, TimeGen offers the same degree of accuracy within the resolution of the computer clock as any official atomic time source.

  1. Workarounds to computer access in healthcare organizations: you want my password or a dead patient?

    Science.gov (United States)

    Koppel, Ross; Smith, Sean; Blythe, Jim; Kothari, Vijay

    2015-01-01

    Workarounds to computer access in healthcare are sufficiently common that they often go unnoticed. Clinicians focus on patient care, not cybersecurity. We argue and demonstrate that understanding workarounds to healthcare workers' computer access requires not only analyses of computer rules, but also interviews and observations with clinicians. In addition, we illustrate the value of shadowing clinicians and conducing focus groups to understand their motivations and tradeoffs for circumvention. Ethnographic investigation of the medical workplace emerges as a critical method of research because in the inevitable conflict between even well-intended people versus the machines, it's the people who are the more creative, flexible, and motivated. We conducted interviews and observations with hundreds of medical workers and with 19 cybersecurity experts, CIOs, CMIOs, CTO, and IT workers to obtain their perceptions of computer security. We also shadowed clinicians as they worked. We present dozens of ways workers ingeniously circumvent security rules. The clinicians we studied were not "black hat" hackers, but just professionals seeking to accomplish their work despite the security technologies and regulations.

  2. Correlative neuroanatomy of computed tomography and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Groot, J.

    1984-01-01

    Since the development of computed tomography (CT) more than a decade ago, still another form of imaging has become available that provides displays of normal and abnormal human structures. Magnetic resonance imaging is given complete coverage in this book. It describes both CT and MR anatomy that explains basic principles and the current status of imaging the brain and spine. The author uses three-dimensional concepts to provide the reader with a simple means to compare the main structures of the brain, skull and spine. Combining normal, gross neuroanatomic illustrations with CT and MR images of normal and abnormal conditions, the book provides diagnostic guidance. Drawings, photographs and radiologic images are used to help

  3. Maxillary sinus augmentation by crestal access: a retrospective study on cavity size and outcome correlation.

    Science.gov (United States)

    Spinato, Sergio; Bernardello, Fabio; Galindo-Moreno, Pablo; Zaffe, Davide

    2015-12-01

    Cone-beam computed tomography (CBCT) and radiographic outcomes of crestal sinus elevation, performed using mineralized human bone allograft, were analyzed to correlate results with maxillary sinus size. A total of 60 sinus augmentations in 60 patients, with initial bone ≤5 mm, were performed. Digital radiographs were taken at surgical implant placement time up to post-prosthetic loading follow-up (12-72 months), when CBCT evaluation was carried out. Marginal bone loss (MBL) was radiographically analyzed at 6 months and follow-up time post-loading. Sinus size (BPD), implant distance from palatal (PID) and buccal wall (BID), and absence of bone coverage of implant (intra-sinus bone loss--IBL) were evaluated and statistically evaluated by ANOVA and linear regression analyses. MBL increased as a function of time. MBL at final follow-up was statistically associated with MBL at 6 months. A statistically significant correlation of IBL with wall distance and of IBL/mm with time was identified with greater values in wide sinuses (WS ≥ 13.27 mm) than in narrow sinuses (NS < 13.27 mm). This study is the first quantitative and statistically significant confirmation that crestal technique with residual ridge height <5 mm is more appropriate and predictable, in terms of intra-sinus bone coverage, in narrow than in WS. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Experimental detection of nonclassical correlations in mixed-state quantum computation

    International Nuclear Information System (INIS)

    Passante, G.; Moussa, O.; Trottier, D. A.; Laflamme, R.

    2011-01-01

    We report on an experiment to detect nonclassical correlations in a highly mixed state. The correlations are characterized by the quantum discord and are observed using four qubits in a liquid-state nuclear magnetic resonance quantum information processor. The state analyzed is the output of a DQC1 computation, whose input is a single quantum bit accompanied by n maximally mixed qubits. This model of computation outperforms the best known classical algorithms and, although it contains vanishing entanglement, it is known to have quantum correlations characterized by the quantum discord. This experiment detects nonvanishing quantum discord, ensuring the existence of nonclassical correlations as measured by the quantum discord.

  5. Computed tomographic findings of splenic injury and correlation with treatment

    International Nuclear Information System (INIS)

    Kim, Dong Jin; Koh, Joo Yaul; Kim, Myung Soon; Hong, In Soo; Cho, Whi Youl; Sung, Ki Joon

    1990-01-01

    According to recently reported classification, 46 patients with blunt splenic trauma were evaluate preoperatively with computed tomography(CT). Injures were graded I through IV and describe as capsular or subcapsular disruptions without parenchymal injury(3 patients); capsular and parenchymal injuries(23 patients); injuries involving hilum(3 patients); and fragmentation(17 patients). Nineteen patients were managed conservatively and 27 patients were managed surgically. Twelve patients(47%) out of those with Type I or Type II were managed surgically including five hemodynamically unstable patients and seven hemodynamically stable patients with associated injuries and unknown surgical criteria. On the other hand hemodynamically stable patients(25%) out of those with Type III or Type IV were managed surgically. The amount of hemoperitoneum was graded into small, moderate and large; small in three patients, moderate in 39 patients, and large in two patients. The amount of hemoperitoneum in patients with conservative treatment was moderate in 16 patients and large in one patient. And the amount of hemoperitoneum in patients with operative treatment was small in three patients, moderate in 23 patients and large in one patient. We concluded that CT was accurate method of determining the extent of splenic injury and evaluation of hemoperitoneum, but treatment choice should be based on the hemodynamic status of patients rather than the type of injury or the amount of hemoperitoneum by CT

  6. Computed tomographic findings of splenic injury and correlation with treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Jin; Koh, Joo Yaul; Kim, Myung Soon; Hong, In Soo; Cho, Whi Youl; Sung, Ki Joon [Yonsei University Wonju College of Medicine, Wonju (Korea, Republic of)

    1990-12-15

    According to recently reported classification, 46 patients with blunt splenic trauma were evaluate preoperatively with computed tomography(CT). Injures were graded I through IV and describe as capsular or subcapsular disruptions without parenchymal injury(3 patients); capsular and parenchymal injuries(23 patients); injuries involving hilum(3 patients); and fragmentation(17 patients). Nineteen patients were managed conservatively and 27 patients were managed surgically. Twelve patients(47%) out of those with Type I or Type II were managed surgically including five hemodynamically unstable patients and seven hemodynamically stable patients with associated injuries and unknown surgical criteria. On the other hand hemodynamically stable patients(25%) out of those with Type III or Type IV were managed surgically. The amount of hemoperitoneum was graded into small, moderate and large; small in three patients, moderate in 39 patients, and large in two patients. The amount of hemoperitoneum in patients with conservative treatment was moderate in 16 patients and large in one patient. And the amount of hemoperitoneum in patients with operative treatment was small in three patients, moderate in 23 patients and large in one patient. We concluded that CT was accurate method of determining the extent of splenic injury and evaluation of hemoperitoneum, but treatment choice should be based on the hemodynamic status of patients rather than the type of injury or the amount of hemoperitoneum by CT.

  7. Computed tomography of laryngeal carcinoma correlated with histopathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yi-Long

    1988-09-01

    Since the development of conservation laryngeal surgery and the advent of computed tomography (CT) scanners, a precise preoperative evaluation of the extent of laryngeal cancer has been of prime importance. Eight patients with known carcinoma of the larynx were examined with CT of the larynx prior to surgery, and whole-mount serial sections of the extirpated larynx were compared with the corresponding level of CT sections to evaluate the reliability of CT during my study abroad in Japan from Dec. 1985 through Dec. 1986. 1. The results indicated that CT scanning accurately delineates the anatomic location and pathologic extent of the tumor three-dimensionally in all cases examined. There is also good demonstration of the anterior commissure and preepiglottic, paraglottic and subglottic spaces which are sometimes poorly seen by laryngoscopy or by any other means. 2. Determination of invasion of the laryngeal cartilage by tumor proved to be very difficult to diagnose with CT. 3. The CT images obtained while the patient is breathing quietly, coupled with additional sections at the level of the vocal cord during slight valsalva maneuver afford good visualization of laryngeal tumors. 4. It should be emphasized that a thorough pathologic examination of extirpated specimens with serial sections is essential for laryngeal surgeons, because it is impossible to determine the patient's prognosis without microscopic demonstration of the degree of invasion.

  8. Nontraumatic frontal lobe hemorrhages: Clinical-computed tomographic correlations

    International Nuclear Information System (INIS)

    Weisberg, L.A.; Stazio, A.; Veterans Administration Hospital, New Orleans, LA; Charity Hospital, New Orleans, LA

    1988-01-01

    Correlation of lesion location and appearance with clinical sequelae in 25 patients with CT-proven frontal lobe hematomas reveals 10 of 25 hematomas were located above the frontal horns of the lateral ventricles. Nine of the 10 patients were normotensive. All presented with contralateral motor and sensory deficits. Four of 25 hematomas were situated inferior to the frontal horns. All these patients were hypertensive, rapidly became comatose and exhibited hemiplegia, hemianestesia and gaze preference contralateral to the hemiplegia. Five patients had frontal hematomas which extended inward from the interhemispheric fissure or caval-septal region. All were normotensive. All had anterior cerebral-anterior communicating artery aneurysms on angiography. Four patients had hematomas involving both the frontal and temporal region. All were normotensive with no known cause for hemorrhage. Two patients had bifrontal hematomas; one had butterfly appearance extending across the interhemispheric fissure and the other was midline but had no interhemispheric blood. Both were normotensive. One had an anterior cerebral-anterior communicating artery aneurysm. (orig.)

  9. Forecasting Model for Network Throughput of Remote Data Access in Computing Grids

    CERN Document Server

    Begy, Volodimir; The ATLAS collaboration

    2018-01-01

    Computing grids are one of the key enablers of eScience. Researchers from many fields (e.g. High Energy Physics, Bioinformatics, Climatology, etc.) employ grids to run computational jobs in a highly distributed manner. The current state of the art approach for data access in the grid is data placement: a job is scheduled to run at a specific data center, and its execution starts only when the complete input data has been transferred there. This approach has two major disadvantages: (1) the jobs are staying idle while waiting for the input data; (2) due to the limited infrastructure resources, the distributed data management system handling the data placement, may queue the transfers up to several days. An alternative approach is remote data access: a job may stream the input data directly from storage elements, which may be located at local or remote data centers. Remote data access brings two innovative benefits: (1) the jobs can be executed asynchronously with respect to the data transfer; (2) when combined...

  10. A Hybrid Scheme for Fine-Grained Search and Access Authorization in Fog Computing Environment

    Science.gov (United States)

    Xiao, Min; Zhou, Jing; Liu, Xuejiao; Jiang, Mingda

    2017-01-01

    In the fog computing environment, the encrypted sensitive data may be transferred to multiple fog nodes on the edge of a network for low latency; thus, fog nodes need to implement a search over encrypted data as a cloud server. Since the fog nodes tend to provide service for IoT applications often running on resource-constrained end devices, it is necessary to design lightweight solutions. At present, there is little research on this issue. In this paper, we propose a fine-grained owner-forced data search and access authorization scheme spanning user-fog-cloud for resource constrained end users. Compared to existing schemes only supporting either index encryption with search ability or data encryption with fine-grained access control ability, the proposed hybrid scheme supports both abilities simultaneously, and index ciphertext and data ciphertext are constructed based on a single ciphertext-policy attribute based encryption (CP-ABE) primitive and share the same key pair, thus the data access efficiency is significantly improved and the cost of key management is greatly reduced. Moreover, in the proposed scheme, the resource constrained end devices are allowed to rapidly assemble ciphertexts online and securely outsource most of decryption task to fog nodes, and mediated encryption mechanism is also adopted to achieve instantaneous user revocation instead of re-encrypting ciphertexts with many copies in many fog nodes. The security and the performance analysis show that our scheme is suitable for a fog computing environment. PMID:28629131

  11. A Hybrid Scheme for Fine-Grained Search and Access Authorization in Fog Computing Environment.

    Science.gov (United States)

    Xiao, Min; Zhou, Jing; Liu, Xuejiao; Jiang, Mingda

    2017-06-17

    In the fog computing environment, the encrypted sensitive data may be transferred to multiple fog nodes on the edge of a network for low latency; thus, fog nodes need to implement a search over encrypted data as a cloud server. Since the fog nodes tend to provide service for IoT applications often running on resource-constrained end devices, it is necessary to design lightweight solutions. At present, there is little research on this issue. In this paper, we propose a fine-grained owner-forced data search and access authorization scheme spanning user-fog-cloud for resource constrained end users. Compared to existing schemes only supporting either index encryption with search ability or data encryption with fine-grained access control ability, the proposed hybrid scheme supports both abilities simultaneously, and index ciphertext and data ciphertext are constructed based on a single ciphertext-policy attribute based encryption (CP-ABE) primitive and share the same key pair, thus the data access efficiency is significantly improved and the cost of key management is greatly reduced. Moreover, in the proposed scheme, the resource constrained end devices are allowed to rapidly assemble ciphertexts online and securely outsource most of decryption task to fog nodes, and mediated encryption mechanism is also adopted to achieve instantaneous user revocation instead of re-encrypting ciphertexts with many copies in many fog nodes. The security and the performance analysis show that our scheme is suitable for a fog computing environment.

  12. Understanding and Improving Blind Students' Access to Visual Information in Computer Science Education

    Science.gov (United States)

    Baker, Catherine M.

    Teaching people with disabilities tech skills empowers them to create solutions to problems they encounter and prepares them for careers. However, computer science is typically taught in a highly visual manner which can present barriers for people who are blind. The goal of this dissertation is to understand and decrease those barriers. The first projects I present looked at the barriers that blind students face. I first present the results of my survey and interviews with blind students with degrees in computer science or related fields. This work highlighted the many barriers that these blind students faced. I then followed-up on one of the barriers mentioned, access to technology, by doing a preliminary accessibility evaluation of six popular integrated development environments (IDEs) and code editors. I found that half were unusable and all had some inaccessible portions. As access to visual information is a barrier in computer science education, I present three projects I have done to decrease this barrier. The first project is Tactile Graphics with a Voice (TGV). This project investigated an alternative to Braille labels for those who do not know Braille and showed that TGV was a potential alternative. The next project was StructJumper, which created a modified abstract syntax tree that blind programmers could use to navigate through code with their screen reader. The evaluation showed that users could navigate more quickly and easily determine the relationships of lines of code when they were using StructJumper compared to when they were not. Finally, I present a tool for dynamic graphs (the type with nodes and edges) which had two different modes for handling focus changes when moving between graphs. I found that the modes support different approaches for exploring the graphs and therefore preferences are mixed based on the user's preferred approach. However, both modes had similar accuracy in completing the tasks. These projects are a first step towards

  13. Correlation Educational Model in Primary Education Curriculum of Mathematics and Computer Science

    Science.gov (United States)

    Macinko Kovac, Maja; Eret, Lidija

    2012-01-01

    This article gives insight into methodical correlation model of teaching mathematics and computer science. The model shows the way in which the related areas of computer science and mathematics can be supplemented, if it transforms the way of teaching and creates a "joint" lessons. Various didactic materials are designed, in which all…

  14. Fencing direct memory access data transfers in a parallel active messaging interface of a parallel computer

    Science.gov (United States)

    Blocksome, Michael A.; Mamidala, Amith R.

    2013-09-03

    Fencing direct memory access (`DMA`) data transfers in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI including data communications endpoints, each endpoint including specifications of a client, a context, and a task, the endpoints coupled for data communications through the PAMI and through DMA controllers operatively coupled to segments of shared random access memory through which the DMA controllers deliver data communications deterministically, including initiating execution through the PAMI of an ordered sequence of active DMA instructions for DMA data transfers between two endpoints, effecting deterministic DMA data transfers through a DMA controller and a segment of shared memory; and executing through the PAMI, with no FENCE accounting for DMA data transfers, an active FENCE instruction, the FENCE instruction completing execution only after completion of all DMA instructions initiated prior to execution of the FENCE instruction for DMA data transfers between the two endpoints.

  15. Computing the correlation between catalyst composition and its performance in the catalysed process

    Czech Academy of Sciences Publication Activity Database

    Holeňa, Martin; Steinfeldt, N.; Baerns, M.; Štefka, David

    2012-01-01

    Roč. 43, 10 August (2012), s. 55-67 ISSN 0098-1354 R&D Projects: GA ČR GA201/08/0802 Institutional support: RVO:67985807 Keywords : catalysed process * catalyst performance * correlation measures * estimating correlation value * analysis of variance * regression trees Subject RIV: IN - Informatics, Computer Science Impact factor: 2.091, year: 2012

  16. SuperB R&D computing program: HTTP direct access to distributed resources

    Science.gov (United States)

    Fella, A.; Bianchi, F.; Ciaschini, V.; Corvo, M.; Delprete, D.; Diacono, D.; Di Simone, A.; Franchini, P.; Donvito, G.; Giacomini, F.; Gianoli, A.; Longo, S.; Luitz, S.; Luppi, E.; Manzali, M.; Pardi, S.; Perez, A.; Rama, M.; Russo, G.; Santeramo, B.; Stroili, R.; Tomassetti, L.

    2012-12-01

    The SuperB asymmetric energy e+e- collider and detector to be built at the newly founded Nicola Cabibbo Lab will provide a uniquely sensitive probe of New Physics in the flavor sector of the Standard Model. Studying minute effects in the heavy quark and heavy lepton sectors requires a data sample of 75 ab-1 and a luminosity target of 1036cm-2s-1. The increasing network performance also in the Wide Area Network environment and the capability to read data remotely with good efficiency are providing new possibilities and opening new scenarios in the data access field. Subjects like data access and data availability in a distributed environment are key points in the definition of the computing model for an HEP experiment like SuperB. R&D efforts in such a field have been brought on during the last year in order to release the Computing Technical Design Report within 2013. WAN direct access to data has been identified as one of the more interesting viable option; robust and reliable protocols as HTTP/WebDAV and xrootd are the subjects of a specific R&D line in a mid-term scenario. In this work we present the R&D results obtained in the study of new data access technologies for typical HEP use cases, focusing on specific protocols such as HTTP and WebDAV in Wide Area Network scenarios. Reports on efficiency, performance and reliability tests performed in a data analysis context have been described. Future R&D plan includes HTTP and xrootd protocols comparison tests, in terms of performance, efficiency, security and features available.

  17. Accessible high performance computing solutions for near real-time image processing for time critical applications

    Science.gov (United States)

    Bielski, Conrad; Lemoine, Guido; Syryczynski, Jacek

    2009-09-01

    High Performance Computing (HPC) hardware solutions such as grid computing and General Processing on a Graphics Processing Unit (GPGPU) are now accessible to users with general computing needs. Grid computing infrastructures in the form of computing clusters or blades are becoming common place and GPGPU solutions that leverage the processing power of the video card are quickly being integrated into personal workstations. Our interest in these HPC technologies stems from the need to produce near real-time maps from a combination of pre- and post-event satellite imagery in support of post-disaster management. Faster processing provides a twofold gain in this situation: 1. critical information can be provided faster and 2. more elaborate automated processing can be performed prior to providing the critical information. In our particular case, we test the use of the PANTEX index which is based on analysis of image textural measures extracted using anisotropic, rotation-invariant GLCM statistics. The use of this index, applied in a moving window, has been shown to successfully identify built-up areas in remotely sensed imagery. Built-up index image masks are important input to the structuring of damage assessment interpretation because they help optimise the workload. The performance of computing the PANTEX workflow is compared on two different HPC hardware architectures: (1) a blade server with 4 blades, each having dual quad-core CPUs and (2) a CUDA enabled GPU workstation. The reference platform is a dual CPU-quad core workstation and the PANTEX workflow total computing time is measured. Furthermore, as part of a qualitative evaluation, the differences in setting up and configuring various hardware solutions and the related software coding effort is presented.

  18. The correlation between a passion for computer games and the school performance of younger schoolchildren.

    Directory of Open Access Journals (Sweden)

    Maliy D.V.

    2015-07-01

    Full Text Available Today computer games occupy a significant place in children’s lives and fundamentally affect the process of the formation and development of their personalities. A number of present-day researchers assert that computer games have a developmental effect on players. Others share the point of view that computer games have negative effects on the cognitive and emotional spheres of a child and claim that children with low self-esteem who neglect their schoolwork and have difficulties in communication are particularly passionate about computer games. This article reviews theoretical and experimental pedagogical and psychological studies of the nature of the correlation between a passion for computer games and the school performance of younger schoolchildren. Our analysis of foreign and Russian psychology studies regarding the problem of playing activities mediated by information and computer technologies allowed us to single out the main criteria for children’s passion for computer games and school performance. This article presents the results of a pilot study of the nature of the correlation between a passion for computer games and the school performance of younger schoolchildren. The research involved 32 pupils (12 girls and 20 boys aged 10-11 years in the 4th grade. The general hypothesis was that there are divergent correlations between the passion of younger schoolchildren for computer games and their school performance. A questionnaire survey administered to the pupils allowed us to obtain information about the amount of time they devoted to computer games, their preferences for computer-game genres, and the extent of their passion for games. To determine the level of school performance we analyzed class registers. To establish the correlation between a passion for computer games and the school performance of younger schoolchildren, as well as to determine the effect of a passion for computer games on the personal qualities of the children

  19. Neural Correlates of Direct Access Trading in a Real Stock Market: An fMRI Investigation.

    Science.gov (United States)

    Raggetti, GianMario; Ceravolo, Maria G; Fattobene, Lucrezia; Di Dio, Cinzia

    2017-01-01

    Background: While financial decision making has been barely explored, no study has previously investigated the neural correlates of individual decisions made by professional traders involved in real stock market negotiations, using their own financial resources. Aim: We sought to detect how different brain areas are modulated by factors like age, expertise, psychological profile (speculative risk seeking or aversion) and, eventually, size and type (Buy/Sell) of stock negotiations, made through Direct Access Trading (DAT) platforms. Subjects and methods: Twenty male traders underwent fMRI while negotiating in the Italian stock market using their own preferred trading platform. Results: At least 20 decision events were collected during each fMRI session. Risk averse traders performed a lower number of financial transactions with respect to risk seekers, with a lower average economic value, but with a higher rate of filled proposals. Activations were observed in cortical and subcortical areas traditionally involved in decision processes, including the ventrolateral and dorsolateral prefrontal cortex (vlPFC, dlPFC), the posterior parietal cortex (PPC), the nucleus accumbens (NAcc), and dorsal striatum. Regression analysis indicated an important role of age in modulating activation of left NAcc, while traders' expertise was negatively related to activation of vlPFC. High value transactions were associated with a stronger activation of the right PPC when subjects' buy rather than sell. The success of the trading activity, based on a large number of filled transactions, was related with higher activation of vlPFC and dlPFC. Independent of chronological and professional age, traders differed in their attitude to DAT, with distinct brain activity profiles being detectable during fMRI sessions. Those subjects who described themselves as very self-confident, showed a lower or absent activation of both the caudate nucleus and the dlPFC, while more reflexive traders showed

  20. Neural Correlates of Direct Access Trading in a Real Stock Market: An fMRI Investigation

    Directory of Open Access Journals (Sweden)

    GianMario Raggetti

    2017-09-01

    Full Text Available Background: While financial decision making has been barely explored, no study has previously investigated the neural correlates of individual decisions made by professional traders involved in real stock market negotiations, using their own financial resources.Aim: We sought to detect how different brain areas are modulated by factors like age, expertise, psychological profile (speculative risk seeking or aversion and, eventually, size and type (Buy/Sell of stock negotiations, made through Direct Access Trading (DAT platforms.Subjects and methods: Twenty male traders underwent fMRI while negotiating in the Italian stock market using their own preferred trading platform.Results: At least 20 decision events were collected during each fMRI session. Risk averse traders performed a lower number of financial transactions with respect to risk seekers, with a lower average economic value, but with a higher rate of filled proposals. Activations were observed in cortical and subcortical areas traditionally involved in decision processes, including the ventrolateral and dorsolateral prefrontal cortex (vlPFC, dlPFC, the posterior parietal cortex (PPC, the nucleus accumbens (NAcc, and dorsal striatum. Regression analysis indicated an important role of age in modulating activation of left NAcc, while traders' expertise was negatively related to activation of vlPFC. High value transactions were associated with a stronger activation of the right PPC when subjects' buy rather than sell. The success of the trading activity, based on a large number of filled transactions, was related with higher activation of vlPFC and dlPFC. Independent of chronological and professional age, traders differed in their attitude to DAT, with distinct brain activity profiles being detectable during fMRI sessions. Those subjects who described themselves as very self-confident, showed a lower or absent activation of both the caudate nucleus and the dlPFC, while more reflexive traders

  1. A Study of the Correlation between Computer Games and Adolescent Behavioral Problems.

    Science.gov (United States)

    Shokouhi-Moqhaddam, Solmaz; Khezri-Moghadam, Noshiravan; Javanmard, Zeinab; Sarmadi-Ansar, Hassan; Aminaee, Mehran; Shokouhi-Moqhaddam, Majid; Zivari-Rahman, Mahmoud

    2013-01-01

    Today, due to developing communicative technologies, computer games and other audio-visual media as social phenomena, are very attractive and have a great effect on children and adolescents. The increasing popularity of these games among children and adolescents results in the public uncertainties about plausible harmful effects of these games. This study aimed to investigate the correlation between computer games and behavioral problems on male guidance school students. This was a descriptive-correlative study on 384 randomly chosen male guidance school students. They were asked to answer the researcher's questionnaire about computer games and Achenbach's Youth Self-Report (YSR). The Results of this study indicated that there was about 95% direct significant correlation between the amount of playing games among adolescents and anxiety/depression, withdrawn/depression, rule-breaking behaviors, aggression, and social problems. However, there was no statistically significant correlation between the amount of computer game usage and physical complaints, thinking problems, and attention problems. In addition, there was a significant correlation between the students' place of living and their parents' job, and using computer games. Computer games lead to anxiety, depression, withdrawal, rule-breaking behavior, aggression, and social problems in adolescents.

  2. A Study of the Correlation between Computer Games and Adolescent Behavioral Problems

    Science.gov (United States)

    Shokouhi-Moqhaddam, Solmaz; Khezri-Moghadam, Noshiravan; Javanmard, Zeinab; Sarmadi-Ansar, Hassan; Aminaee, Mehran; Shokouhi-Moqhaddam, Majid; Zivari-Rahman, Mahmoud

    2013-01-01

    Background Today, due to developing communicative technologies, computer games and other audio-visual media as social phenomena, are very attractive and have a great effect on children and adolescents. The increasing popularity of these games among children and adolescents results in the public uncertainties about plausible harmful effects of these games. This study aimed to investigate the correlation between computer games and behavioral problems on male guidance school students. Methods This was a descriptive-correlative study on 384 randomly chosen male guidance school students. They were asked to answer the researcher's questionnaire about computer games and Achenbach’s Youth Self-Report (YSR). Findings The Results of this study indicated that there was about 95% direct significant correlation between the amount of playing games among adolescents and anxiety/depression, withdrawn/depression, rule-breaking behaviors, aggression, and social problems. However, there was no statistically significant correlation between the amount of computer game usage and physical complaints, thinking problems, and attention problems. In addition, there was a significant correlation between the students’ place of living and their parents’ job, and using computer games. Conclusion Computer games lead to anxiety, depression, withdrawal, rule-breaking behavior, aggression, and social problems in adolescents. PMID:24494157

  3. Metal oxide resistive random access memory based synaptic devices for brain-inspired computing

    Science.gov (United States)

    Gao, Bin; Kang, Jinfeng; Zhou, Zheng; Chen, Zhe; Huang, Peng; Liu, Lifeng; Liu, Xiaoyan

    2016-04-01

    The traditional Boolean computing paradigm based on the von Neumann architecture is facing great challenges for future information technology applications such as big data, the Internet of Things (IoT), and wearable devices, due to the limited processing capability issues such as binary data storage and computing, non-parallel data processing, and the buses requirement between memory units and logic units. The brain-inspired neuromorphic computing paradigm is believed to be one of the promising solutions for realizing more complex functions with a lower cost. To perform such brain-inspired computing with a low cost and low power consumption, novel devices for use as electronic synapses are needed. Metal oxide resistive random access memory (ReRAM) devices have emerged as the leading candidate for electronic synapses. This paper comprehensively addresses the recent work on the design and optimization of metal oxide ReRAM-based synaptic devices. A performance enhancement methodology and optimized operation scheme to achieve analog resistive switching and low-energy training behavior are provided. A three-dimensional vertical synapse network architecture is proposed for high-density integration and low-cost fabrication. The impacts of the ReRAM synaptic device features on the performances of neuromorphic systems are also discussed on the basis of a constructed neuromorphic visual system with a pattern recognition function. Possible solutions to achieve the high recognition accuracy and efficiency of neuromorphic systems are presented.

  4. The CT Scanner Facility at Stellenbosch University: An open access X-ray computed tomography laboratory

    Science.gov (United States)

    du Plessis, Anton; le Roux, Stephan Gerhard; Guelpa, Anina

    2016-10-01

    The Stellenbosch University CT Scanner Facility is an open access laboratory providing non-destructive X-ray computed tomography (CT) and a high performance image analysis services as part of the Central Analytical Facilities (CAF) of the university. Based in Stellenbosch, South Africa, this facility offers open access to the general user community, including local researchers, companies and also remote users (both local and international, via sample shipment and data transfer). The laboratory hosts two CT instruments, i.e. a micro-CT system, as well as a nano-CT system. A workstation-based Image Analysis Centre is equipped with numerous computers with data analysis software packages, which are to the disposal of the facility users, along with expert supervision, if required. All research disciplines are accommodated at the X-ray CT laboratory, provided that non-destructive analysis will be beneficial. During its first four years, the facility has accommodated more than 400 unique users (33 in 2012; 86 in 2013; 154 in 2014; 140 in 2015; 75 in first half of 2016), with diverse industrial and research applications using X-ray CT as means. This paper summarises the existence of the laboratory's first four years by way of selected examples, both from published and unpublished projects. In the process a detailed description of the capabilities and facilities available to users is presented.

  5. The CT Scanner Facility at Stellenbosch University: An open access X-ray computed tomography laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Plessis, Anton du, E-mail: anton2@sun.ac.za [CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch (South Africa); Physics Department, Stellenbosch University, Stellenbosch (South Africa); Roux, Stephan Gerhard le, E-mail: lerouxsg@sun.ac.za [CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch (South Africa); Guelpa, Anina, E-mail: aninag@sun.ac.za [CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch (South Africa)

    2016-10-01

    The Stellenbosch University CT Scanner Facility is an open access laboratory providing non-destructive X-ray computed tomography (CT) and a high performance image analysis services as part of the Central Analytical Facilities (CAF) of the university. Based in Stellenbosch, South Africa, this facility offers open access to the general user community, including local researchers, companies and also remote users (both local and international, via sample shipment and data transfer). The laboratory hosts two CT instruments, i.e. a micro-CT system, as well as a nano-CT system. A workstation-based Image Analysis Centre is equipped with numerous computers with data analysis software packages, which are to the disposal of the facility users, along with expert supervision, if required. All research disciplines are accommodated at the X-ray CT laboratory, provided that non-destructive analysis will be beneficial. During its first four years, the facility has accommodated more than 400 unique users (33 in 2012; 86 in 2013; 154 in 2014; 140 in 2015; 75 in first half of 2016), with diverse industrial and research applications using X-ray CT as means. This paper summarises the existence of the laboratory’s first four years by way of selected examples, both from published and unpublished projects. In the process a detailed description of the capabilities and facilities available to users is presented.

  6. CORRELATION AMONG DAMAGES CAUSED BY YELLOW BEETLE, CLIMATOLOGICAL ELEMENTS AND PRODUCTION OF GUAVA ACCESSES GROWN IN ORGANIC SYSTEM

    Directory of Open Access Journals (Sweden)

    JULIANA ALTAFIN GALLI

    Full Text Available ABSTRACT The objective of this research was evaluate the damage caused by the yellow beetle on 85 guava accessions and correlations of the damage with the climatological elements and the production of fruit in an orchard of guava conducted in organic system. Ten leaves by access were analyzed containing the injury of insect attack. Each leaf had its foliar area measured by leaf area meter and, after obtaining the total area, the leaf was covered with duct tape, and measure again. The averages were compared by Scott-Knott test at 5% probability. The 15 accessions with highest average damage had the data submitted to the correlation with the minimum and maximum temperature, precipitation and relative humidity. The production was obtained by the number of fruits/plant. The damages are negatively correlated with the mean relative humidity of 7:00h (local time in the period of 14 days prior to the assessments, and negatively affect production. The accessions Saito, L4P16, Monte Alto Comum 1 and L5P19 are promising in organic agriculture, for presenting good production and minor damage to insect attack, when compared to others.

  7. Training to use a commercial brain-computer interface as access technology: a case study.

    Science.gov (United States)

    Taherian, Sarvnaz; Selitskiy, Dmitry; Pau, James; Davies, T Claire; Owens, R Glynn

    2016-01-01

    This case study describes how an individual with spastic quadriplegic cerebral palsy was trained over a period of four weeks to use a commercial electroencephalography (EEG)-based brain-computer interface (BCI). The participant spent three sessions exploring the system, and seven sessions playing a game focused on EEG feedback training of left and right arm motor imagery and a customised, training game paradigm was employed. The participant showed improvement in the production of two distinct EEG patterns. The participant's performance was influenced by motivation, fatigue and concentration. Six weeks post-training the participant could still control the BCI and used this to type a sentence using an augmentative and alternative communication application on a wirelessly linked device. The results from this case study highlight the importance of creating a dynamic, relevant and engaging training environment for BCIs. Implications for Rehabilitation Customising a training paradigm to suit the users' interests can influence adherence to assistive technology training. Mood, fatigue, physical illness and motivation influence the usability of a brain-computer interface. Commercial brain-computer interfaces, which require little set up time, may be used as access technology for individuals with severe disabilities.

  8. Fast Computation of the Two-Point Correlation Function in the Age of Big Data

    Science.gov (United States)

    Pellegrino, Andrew; Timlin, John

    2018-01-01

    We present a new code which quickly computes the two-point correlation function for large sets of astronomical data. This code combines the ease of use of Python with the speed of parallel shared libraries written in C. We include the capability to compute the auto- and cross-correlation statistics, and allow the user to calculate the three-dimensional and angular correlation functions. Additionally, the code automatically divides the user-provided sky masks into contiguous subsamples of similar size, using the HEALPix pixelization scheme, for the purpose of resampling. Errors are computed using jackknife and bootstrap resampling in a way that adds negligible extra runtime, even with many subsamples. We demonstrate comparable speed with other clustering codes, and code accuracy compared to known and analytic results.

  9. Neural correlates and neural computations in posterior parietal cortex during perceptual decision-making

    Directory of Open Access Journals (Sweden)

    Alexander eHuk

    2012-10-01

    Full Text Available A recent line of work has found remarkable success in relating perceptual decision-making and the spiking activity in the macaque lateral intraparietal area (LIP. In this review, we focus on questions about the neural computations in LIP that are not answered by demonstrations of neural correlates of psychological processes. We highlight three areas of limitations in our current understanding of the precise neural computations that might underlie neural correlates of decisions: (1 empirical questions not yet answered by existing data; (2 implementation issues related to how neural circuits could actually implement the mechanisms suggested by both physiology and psychology; and (3 ecological constraints related to the use of well-controlled laboratory tasks and whether they provide an accurate window on sensorimotor computation. These issues motivate the adoption of a more general encoding-decoding framework that will be fruitful for more detailed contemplation of how neural computations in LIP relate to the formation of perceptual decisions.

  10. A Study of the Correlation between Computer Games and Adolescent Behavioral Problems

    OpenAIRE

    Shokouhi-Moqhaddam, Solmaz; Khezri-Moghadam, Noshiravan; Javanmard, Zeinab; Sarmadi-Ansar, Hassan; Aminaee, Mehran; Shokouhi-Moqhaddam, Majid; Zivari-Rahman, Mahmoud

    2013-01-01

    Background Today, due to developing communicative technologies, computer games and other audio-visual media as social phenomena, are very attractive and have a great effect on children and adolescents. The increasing popularity of these games among children and adolescents results in the public uncertainties about plausible harmful effects of these games. This study aimed to investigate the correlation between computer games and behavioral problems on male guidance school students. Methods Th...

  11. Computing Coherence Vectors and Correlation Matrices with Application to Quantum Discord Quantification

    Directory of Open Access Journals (Sweden)

    Jonas Maziero

    2016-01-01

    Full Text Available Coherence vectors and correlation matrices are important functions frequently used in physics. The numerical calculation of these functions directly from their definitions, which involves Kronecker products and matrix multiplications, may seem to be a reasonable option. Notwithstanding, as we demonstrate in this paper, some algebraic manipulations before programming can reduce considerably their computational complexity. Besides, we provide Fortran code to generate generalized Gell-Mann matrices and to compute the optimized and unoptimized versions of associated Bloch’s vectors and correlation matrix in the case of bipartite quantum systems. As a code test and application example, we consider the calculation of Hilbert-Schmidt quantum discords.

  12. On the computation of molecular surface correlations for protein docking using fourier techniques.

    Science.gov (United States)

    Sakk, Eric

    2007-08-01

    The computation of surface correlations using a variety of molecular models has been applied to the unbound protein docking problem. Because of the computational complexity involved in examining all possible molecular orientations, the fast Fourier transform (FFT) (a fast numerical implementation of the discrete Fourier transform (DFT)) is generally applied to minimize the number of calculations. This approach is rooted in the convolution theorem which allows one to inverse transform the product of two DFTs in order to perform the correlation calculation. However, such a DFT calculation results in a cyclic or "circular" correlation which, in general, does not lead to the same result as the linear correlation desired for the docking problem. In this work, we provide computational bounds for constructing molecular models used in the molecular surface correlation problem. The derived bounds are then shown to be consistent with various intuitive guidelines previously reported in the protein docking literature. Finally, these bounds are applied to different molecular models in order to investigate their effect on the correlation calculation.

  13. Guided Endodontic Access in Maxillary Molars Using Cone-beam Computed Tomography and Computer-aided Design/Computer-aided Manufacturing System: A Case Report.

    Science.gov (United States)

    Lara-Mendes, Sônia T de O; Barbosa, Camila de Freitas M; Santa-Rosa, Caroline C; Machado, Vinícius C

    2018-05-01

    The aim of this study was to describe a guided endodontic technique that facilitates access to root canals of molars presenting with pulp calcifications. A 61-year-old woman presented to our service with pain in the upper left molar region. The second and third left molars showed signs of apical periodontitis confirmed by the cone-beam computed tomographic (CBCT) scans brought to us by the patient at the initial appointment. Conventional endodontic treatment was discontinued given the difficulty in locating the root canals. Intraoral scanning and the CBCT scans were used to plan the access to the calcified canals by means of implant planning software. Guides were fabricated through rapid prototyping and allowed for the correct orientation of a cylindrical drill used to provide access through the calcifications. Second to that, the root canals were prepared with reciprocating endodontic instruments and rested for 2 weeks with intracanal medication. Subsequently, canals were packed with gutta-percha cones using the hydraulic compression technique. Permanent restorations of the access cavities were performed. By comparing the tomographic images, the authors observed a drastic reduction of the periapical lesions as well as the absence of pain symptoms after 3 months. This condition was maintained at the 1-year follow-up. The guided endodontic technique in maxillary molars was shown to be a fast, safe, and predictable therapy and can be regarded as an excellent option for the location of calcified root canals, avoiding failures in complex cases. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. Characterizing Computer Access Using a One-Channel EEG Wireless Sensor.

    Science.gov (United States)

    Molina-Cantero, Alberto J; Guerrero-Cubero, Jaime; Gómez-González, Isabel M; Merino-Monge, Manuel; Silva-Silva, Juan I

    2017-06-29

    This work studies the feasibility of using mental attention to access a computer. Brain activity was measured with an electrode placed at the Fp1 position and the reference on the left ear; seven normally developed people and three subjects with cerebral palsy (CP) took part in the experimentation. They were asked to keep their attention high and low for as long as possible during several trials. We recorded attention levels and power bands conveyed by the sensor, but only the first was used for feedback purposes. All of the information was statistically analyzed to find the most significant parameters and a classifier based on linear discriminant analysis (LDA) was also set up. In addition, 60% of the participants were potential users of this technology with an accuracy of over 70%. Including power bands in the classifier did not improve the accuracy in discriminating between the two attentional states. For most people, the best results were obtained by using only the attention indicator in classification. Tiredness was higher in the group with disabilities (2.7 in a scale of 3) than in the other (1.5 in the same scale); and modulating the attention to access a communication board requires that it does not contain many pictograms (between 4 and 7) on screen and has a scanning period of a relatively high t s c a n ≈ 10 s. The information transfer rate (ITR) is similar to the one obtained by other brain computer interfaces (BCI), like those based on sensorimotor rhythms (SMR) or slow cortical potentials (SCP), and makes it suitable as an eye-gaze independent BCI.

  15. 3D CFD computations of trasitional flows using DES and a correlation based transition model

    DEFF Research Database (Denmark)

    Sørensen, Niels N.; Bechmann, Andreas; Zahle, Frederik

    2011-01-01

    a circular cylinder from Re = 10 to 1 × 106 reproducing the cylinder drag crisis. The computations show good quantitative and qualitative agreement with the behaviour seen in experiments. This case shows that the methodology performs smoothly from the laminar cases at low Re to the turbulent cases at high Re......The present article describes the application of the correlation based transition model of Menter et al. in combination with the Detached Eddy Simulation (DES) methodology to two cases with large degree of flow separation typically considered difficult to compute. Firstly, the flow is computed over...

  16. Renormalization group improved computation of correlation functions in theories with nontrivial phase diagram

    DEFF Research Database (Denmark)

    Codello, Alessandro; Tonero, Alberto

    2016-01-01

    We present a simple and consistent way to compute correlation functions in interacting theories with nontrivial phase diagram. As an example we show how to consistently compute the four-point function in three dimensional Z2-scalar theories. The idea is to perform the path integral by weighting...... the momentum modes that contribute to it according to their renormalization group (RG) relevance, i.e. we weight each mode according to the value of the running couplings at that scale. In this way, we are able to encode in a loop computation the information regarding the RG trajectory along which we...

  17. Experiences of registered nurses with regard to accessing health information at the point-of-care via mobile computing devices.

    Science.gov (United States)

    Ricks, Esmeralda; Benjamin, Valencia; Williams, Margaret

    2015-11-19

    The volume of health information necessary to provide competent health care today has become overwhelming. Mobile computing devices are fast becoming an essential clinical tool for accessing health information at the point-of-care of patients. This study explored and described how registered nurses experienced accessing information at the point-of-care via mobile computing devices (MCDs). A qualitative, exploratory, descriptive and contextual design was used. Ten in-depth interviews were conducted with purposively sampled registered nurses employed by a state hospital in the Nelson Mandela Bay Municipality (NMBM). Interviews were recorded, transcribed verbatim and analysed using Tesch's data analysis technique. Ethical principles were adhered to throughout the study. Guba's model of trustworthiness was used to confirm integrity of the study. Four themes emerged which revealed that the registered nurses benefited from the training they received by enabling them to develop, and improve, their computer literacy levels. Emphasis was placed on the benefits that the accessed information had for educational purposes for patients and the public, for colleagues and students. Furthermore the ability to access information at the point-of-care was considered by registered nurses as valuable to improve patient care because of the wide range of accurate and readily accessible information available via the mobile computing device. The registered nurses in this study felt that being able to access information at the point-of-care increased their confidence and facilitated the provision of quality care because it assisted them in being accurate and sure of what they were doing.

  18. A Correlational Analysis: Electronic Health Records (EHR) and Quality of Care in Critical Access Hospitals

    Science.gov (United States)

    Khan, Arshia A.

    2012-01-01

    Driven by the compulsion to improve the evident paucity in quality of care, especially in critical access hospitals in the United States, policy makers, healthcare providers, and administrators have taken the advise of researchers suggesting the integration of technology in healthcare. The Electronic Health Record (EHR) System composed of multiple…

  19. Assessing mouse alternatives to access to computer: a case study of a user with cerebral palsy.

    Science.gov (United States)

    Pousada, Thais; Pareira, Javier; Groba, Betania; Nieto, Laura; Pazos, Alejandro

    2014-01-01

    The purpose of this study is to describe the process of assessment of three assistive devices to meet the needs of a woman with cerebral palsy (CP) in order to provide her with computer access and use. The user has quadriplegic CP, with anarthria, using a syllabic keyboard. Devices were evaluated through a three-step approach: (a) use of a questionnaire to preselect potential assistive technologies, (b) use of an eTAO tool to determine the effectiveness of each devised, and (c) a conducting semi-structured interview to obtain qualitative data. Touch screen, joystick, and trackball were the preselected devices. The best device that met the user's needs and priorities was joystick. The finding was corroborated by both the eTAO tool and the semi-structured interview. Computers are a basic form of social participation. It is important to consider the special needs and priorities of users and to try different devices when undertaking a device-selection process. Environmental and personal factors have to be considered, as well. This leads to a need to evaluate new tools in order to provide the appropriate support. The eTAO could be a suitable instrument for this purpose. Additional research is also needed to understand how to better match devices with different user populations and how to comprehensively evaluate emerging technologies relative to users with disabilities.

  20. Testing a bedside personal computer Clinical Care Classification System for nursing students using Microsoft Access.

    Science.gov (United States)

    Feeg, Veronica D; Saba, Virginia K; Feeg, Alan N

    2008-01-01

    This study tested a personal computer-based version of the Sabacare Clinical Care Classification System on students' performance of charting patient care plans. The application was designed as an inexpensive alternative to teach electronic charting for use on any laptop or personal computer with Windows and Microsoft Access. The data-based system was tested in a randomized trial with the control group using a type-in text-based-only system also mounted on a laptop at the bedside in the laboratory. Student care plans were more complete using the data-based system over the type-in text version. Students were more positive but not necessarily more efficient with the data-based system. The results demonstrate that the application is effective for improving student nursing care charting using the nursing process and capturing patient care information with a language that is standardized and ready for integration with other patient electronic health record data. It can be implemented on a bedside stand in the clinical laboratory or used to aggregate care planning over a student's clinical experience.

  1. The Cognitive Correlates of Third-Grade Skill in Arithmetic, Algorithmic Computation, and Arithmetic Word Problems

    Science.gov (United States)

    Fuchs, Lynn S.; Fuchs, Douglas; Compton, Donald L.; Powell, Sarah R.; Seethaler, Pamela M.; Capizzi, Andrea M.; Schatschneider, Christopher; Fletcher, Jack M.

    2006-01-01

    The purpose of this study was to examine the cognitive correlates of RD-grade skill in arithmetic, algorithmic computation, and arithmetic word problems. Third graders (N = 312) were measured on language, nonverbal problem solving, concept formation, processing speed, long-term memory, working memory, phonological decoding, and sight word…

  2. Pipeline leak detection and location by on-line-correlation with a process computer

    International Nuclear Information System (INIS)

    Siebert, H.; Isermann, R.

    1977-01-01

    A method for leak detection using a correlation technique in pipelines is described. For leak detection and also for leak localisation and estimation of the leak flow recursive estimation algorithms are used. The efficiency of the methods is demonstrated with a process computer and a pipeline model operating on-line. It is shown that very small leaks can be detected. (orig.) [de

  3. Correlation of computed tomographic and magnetic resonance imaging findings in cerebral infartion

    International Nuclear Information System (INIS)

    Komatsubara, Chizuko; Chuda, Moriyoshi; Taka, Toshihiko

    1989-01-01

    We evaluated neurological findings in 75 patients of cerebral infarction, and correlated computed tomographic (CT) and magnetic resonance imaging (MRI) findings. MRI was found to have the advantage when the lesion were multiple, or in the posterior fossa. MRI demonstrates the anatomical details, and lacks the bony artifact, so it is an excellent method for identification of cerebral infarction. (author)

  4. Computers in plasma physics: remote data access and magnetic configuration design

    International Nuclear Information System (INIS)

    Blackwell, B.D.; McMillan, B.F.; Searle, A.C.; Gardner, H.J.; Price, D.M.; Fredian, T.W.

    2000-01-01

    Full text: Two graphically intensive examples of the application of computers in plasma physics are described remote data access for plasma confinement experiments, and a code for real-time magnetic field tracing and optimisation. The application for both of these is the H-1NF National Plasma Fusion Research Facility, a Commonwealth Major National Research Facility within the Research School of Physical Science, Institute of Advanced Studies, ANU. It is based on the 'flexible' heliac stellarator H-1, a plasma confinement device in which the confining fields are generated solely by external conductors. These complex, fully three dimensional magnetic fields are used as examples for the magnetic design application, and data from plasma physics experiments are used to illustrate the remote access techniques. As plasma fusion experiments grow in size, increased remote access allows physicists to participate in experiments and data analysis from their home base. Three types of access will be described and demonstrated - a simple Java-based web interface, an example TCP client-server built around the widely used MDSPlus data system and the visualisation package IDL (RSI Inc), and a virtual desktop Environment (VNC: AT and T Research) that simulates terminals local to the plasma facility. A client server TCP/IP - web interface to the programmable logic controller that provides user interface to the programmable high power magnet power supplies is described. A very general configuration file allows great flexibility, and allows new displays and interfaces to be created (usually) without changes to the underlying C++ and Java code. The magnetic field code BLINE provides accurate calculation of complex magnetic fields, and 3D visualisation in real time, using a low cost multiprocessor computer and an OpenGL-compatible graphics accelerator. A fast, flexible multi-mesh interpolation method is used for tracing vacuum magnetic field lines created by arbitrary filamentary

  5. Field transients of coherent terahertz synchrotron radiation accessed via time-resolving and correlation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pohl, A.; Hübers, H.-W. [Humboldt-Universität zu Berlin, Institute of Physics, Newtonstraße 15, 12489 Berlin (Germany); Institute of Optical Sensor Systems, German Aerospace Center (DLR), Rutherfordstrasse 29, 12489 Berlin (Germany); Semenov, A. [Institute of Optical Sensor Systems, German Aerospace Center (DLR), Rutherfordstrasse 29, 12489 Berlin (Germany); Hoehl, A.; Ulm, G. [Physikalisch-Technische Bundesanstalt (PTB), Abbestraße 2-12, 10587 Berlin (Germany); Ries, M.; Wüstefeld, G. [Helmholz-Zentrum Berlin, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Ilin, K.; Thoma, P.; Siegel, M. [Institute of Micro- and Nanoelectronic Systems, Karlsruhe Institute of Technology (KIT), Hertzstrasse 16, 76187 Karlsruhe (Germany)

    2016-03-21

    Decaying oscillations of the electric field in repetitive pulses of coherent synchrotron radiation in the terahertz frequency range was evaluated by means of time-resolving and correlation techniques. Comparative analysis of real-time voltage transients of the electrical response and interferograms, which were obtained with an ultrafast zero-bias Schottky diode detector and a Martin-Puplett interferometer, delivers close values of the pulse duration. Consistent results were obtained via the correlation technique with a pair of Golay Cell detectors and a pair of resonant polarisation-sensitive superconducting detectors integrated on one chip. The duration of terahertz synchrotron pulses does not closely correlate with the duration of single-cycle electric field expected for the varying size of electron bunches. We largely attribute the difference to the charge density oscillations in electron bunches and to the low-frequency spectral cut-off imposed by both the synchrotron beamline and the coupling optics of our detectors.

  6. F2AC: A Lightweight, Fine-Grained, and Flexible Access Control Scheme for File Storage in Mobile Cloud Computing

    Directory of Open Access Journals (Sweden)

    Wei Ren

    2016-01-01

    Full Text Available Current file storage service models for cloud servers assume that users either belong to single layer with different privileges or cannot authorize privileges iteratively. Thus, the access control is not fine-grained and flexible. Besides, most access control methods at cloud servers mainly rely on computationally intensive cryptographic algorithms and, especially, may not be able to support highly dynamic ad hoc groups with addition and removal of group members. In this paper, we propose a scheme called F2AC, which is a lightweight, fine-grained, and flexible access control scheme for file storage in mobile cloud computing. F2AC can not only achieve iterative authorization, authentication with tailored policies, and access control for dynamically changing accessing groups, but also provide access privilege transition and revocation. A new access control model called directed tree with linked leaf model is proposed for further implementations in data structures and algorithms. The extensive analysis is given for justifying the soundness and completeness of F2AC.

  7. Low Computational Signal Acquisition for GNSS Receivers Using a Resampling Strategy and Variable Circular Correlation Time

    Directory of Open Access Journals (Sweden)

    Yeqing Zhang

    2018-02-01

    Full Text Available For the objective of essentially decreasing computational complexity and time consumption of signal acquisition, this paper explores a resampling strategy and variable circular correlation time strategy specific to broadband multi-frequency GNSS receivers. In broadband GNSS receivers, the resampling strategy is established to work on conventional acquisition algorithms by resampling the main lobe of received broadband signals with a much lower frequency. Variable circular correlation time is designed to adapt to different signal strength conditions and thereby increase the operation flexibility of GNSS signal acquisition. The acquisition threshold is defined as the ratio of the highest and second highest correlation results in the search space of carrier frequency and code phase. Moreover, computational complexity of signal acquisition is formulated by amounts of multiplication and summation operations in the acquisition process. Comparative experiments and performance analysis are conducted on four sets of real GPS L2C signals with different sampling frequencies. The results indicate that the resampling strategy can effectively decrease computation and time cost by nearly 90–94% with just slight loss of acquisition sensitivity. With circular correlation time varying from 10 ms to 20 ms, the time cost of signal acquisition has increased by about 2.7–5.6% per millisecond, with most satellites acquired successfully.

  8. Low Computational Signal Acquisition for GNSS Receivers Using a Resampling Strategy and Variable Circular Correlation Time

    Science.gov (United States)

    Zhang, Yeqing; Wang, Meiling; Li, Yafeng

    2018-01-01

    For the objective of essentially decreasing computational complexity and time consumption of signal acquisition, this paper explores a resampling strategy and variable circular correlation time strategy specific to broadband multi-frequency GNSS receivers. In broadband GNSS receivers, the resampling strategy is established to work on conventional acquisition algorithms by resampling the main lobe of received broadband signals with a much lower frequency. Variable circular correlation time is designed to adapt to different signal strength conditions and thereby increase the operation flexibility of GNSS signal acquisition. The acquisition threshold is defined as the ratio of the highest and second highest correlation results in the search space of carrier frequency and code phase. Moreover, computational complexity of signal acquisition is formulated by amounts of multiplication and summation operations in the acquisition process. Comparative experiments and performance analysis are conducted on four sets of real GPS L2C signals with different sampling frequencies. The results indicate that the resampling strategy can effectively decrease computation and time cost by nearly 90–94% with just slight loss of acquisition sensitivity. With circular correlation time varying from 10 ms to 20 ms, the time cost of signal acquisition has increased by about 2.7–5.6% per millisecond, with most satellites acquired successfully. PMID:29495301

  9. Secure Data Access Control for Fog Computing Based on Multi-Authority Attribute-Based Signcryption with Computation Outsourcing and Attribute Revocation.

    Science.gov (United States)

    Xu, Qian; Tan, Chengxiang; Fan, Zhijie; Zhu, Wenye; Xiao, Ya; Cheng, Fujia

    2018-05-17

    Nowadays, fog computing provides computation, storage, and application services to end users in the Internet of Things. One of the major concerns in fog computing systems is how fine-grained access control can be imposed. As a logical combination of attribute-based encryption and attribute-based signature, Attribute-based Signcryption (ABSC) can provide confidentiality and anonymous authentication for sensitive data and is more efficient than traditional "encrypt-then-sign" or "sign-then-encrypt" strategy. Thus, ABSC is suitable for fine-grained access control in a semi-trusted cloud environment and is gaining more and more attention recently. However, in many existing ABSC systems, the computation cost required for the end users in signcryption and designcryption is linear with the complexity of signing and encryption access policy. Moreover, only a single authority that is responsible for attribute management and key generation exists in the previous proposed ABSC schemes, whereas in reality, mostly, different authorities monitor different attributes of the user. In this paper, we propose OMDAC-ABSC, a novel data access control scheme based on Ciphertext-Policy ABSC, to provide data confidentiality, fine-grained control, and anonymous authentication in a multi-authority fog computing system. The signcryption and designcryption overhead for the user is significantly reduced by outsourcing the undesirable computation operations to fog nodes. The proposed scheme is proven to be secure in the standard model and can provide attribute revocation and public verifiability. The security analysis, asymptotic complexity comparison, and implementation results indicate that our construction can balance the security goals with practical efficiency in computation.

  10. Toward a Computer Vision-based Wayfinding Aid for Blind Persons to Access Unfamiliar Indoor Environments.

    Science.gov (United States)

    Tian, Yingli; Yang, Xiaodong; Yi, Chucai; Arditi, Aries

    2013-04-01

    Independent travel is a well known challenge for blind and visually impaired persons. In this paper, we propose a proof-of-concept computer vision-based wayfinding aid for blind people to independently access unfamiliar indoor environments. In order to find different rooms (e.g. an office, a lab, or a bathroom) and other building amenities (e.g. an exit or an elevator), we incorporate object detection with text recognition. First we develop a robust and efficient algorithm to detect doors, elevators, and cabinets based on their general geometric shape, by combining edges and corners. The algorithm is general enough to handle large intra-class variations of objects with different appearances among different indoor environments, as well as small inter-class differences between different objects such as doors and door-like cabinets. Next, in order to distinguish intra-class objects (e.g. an office door from a bathroom door), we extract and recognize text information associated with the detected objects. For text recognition, we first extract text regions from signs with multiple colors and possibly complex backgrounds, and then apply character localization and topological analysis to filter out background interference. The extracted text is recognized using off-the-shelf optical character recognition (OCR) software products. The object type, orientation, location, and text information are presented to the blind traveler as speech.

  11. Cross-Cultural adaptation of an instrument to computer accessibility evaluation for students with cerebral palsy

    Directory of Open Access Journals (Sweden)

    Gerusa Ferreira Lourenço

    2015-03-01

    Full Text Available The specific literature indicates that the successful education of children with cerebral palsy may require the implementation of appropriate assistive technology resources, allowing students to improve their performance and complete everyday tasks more efficiently and independently. To this end, these resources must be selected properly, emphasizing the importance of an appropriate initial assessment of the child and the possibilities of the resources available. The present study aimed to translate and adapt theoretically an American instrument that evaluates computer accessibility for people with cerebral palsy, in order to contextualize it for applicability to Brazilian students with cerebral palsy. The methodology involved the steps of translation and cross-cultural adaptation of this instrument, as well as the construction of a supplementary script for additional use of that instrument in the educational context. Translation procedures, theoretical and technical adaptation of the American instrument and theoretical analysis (content and semantics were carried out with the participation of professional experts of the special education area as adjudicators. The results pointed to the relevance of the proposal of the translated instrument in conjunction with the script built to the reality of professionals involved with the education of children with cerebral palsy, such as occupational therapists and special educators.

  12. BioSPICE: access to the most current computational tools for biologists.

    Science.gov (United States)

    Garvey, Thomas D; Lincoln, Patrick; Pedersen, Charles John; Martin, David; Johnson, Mark

    2003-01-01

    The goal of the BioSPICE program is to create a framework that provides biologists access to the most current computational tools. At the program midpoint, the BioSPICE member community has produced a software system that comprises contributions from approximately 20 participating laboratories integrated under the BioSPICE Dashboard and a methodology for continued software integration. These contributed software modules are the BioSPICE Dashboard, a graphical environment that combines Open Agent Architecture and NetBeans software technologies in a coherent, biologist-friendly user interface. The current Dashboard permits data sources, models, simulation engines, and output displays provided by different investigators and running on different machines to work together across a distributed, heterogeneous network. Among several other features, the Dashboard enables users to create graphical workflows by configuring and connecting available BioSPICE components. Anticipated future enhancements to BioSPICE include a notebook capability that will permit researchers to browse and compile data to support model building, a biological model repository, and tools to support the development, control, and data reduction of wet-lab experiments. In addition to the BioSPICE software products, a project website supports information exchange and community building.

  13. Data acquisition card for fluctuation correlation spectroscopy allowing full access to the detected photon sequence

    OpenAIRE

    Eid, JS; Muller, JD; Gratton, E

    2000-01-01

    Typically, fluctuation correlation spectroscopy (FCS) data acquisition cards measure the number of photon events per time interval (i.e., bin) - time mode. Commercial FCS cards combine the bins through hardware in order to calculate the autocorrelation function. Such a design therefore does not yield the time resolved photon sequence, but only the autocorrelation of that sequence. A different acquisition method which measures the number of time intervals between photon events has been impleme...

  14. Malignant hemangiopericytoma. A correlative study of angiography, computed tomography, and pathology

    Energy Technology Data Exchange (ETDEWEB)

    Higa, Toshiaki; Kuroda, Yasumasa; Kobashi, Yoichiro; Ichijima, Kunio; Odori, Teruo; Torizuka, Kanji [Kyoto Univ. (Japan). Hospital

    1983-01-01

    Four cases of primary and secondary malignant hemangiopericytoma were correlatively studied using selective angiography, computed tomography, and pathologic specimens. One case was found in each of the peritoneal space (metastasis), the left middle cranial fossa, the left thigh, and the left retroperitoneal space. Basic angiographic features of the tumor were a few feeding arteries entering the tumor with radially arranged fine network throughout, early visualization of veins due to A-V shunting, and a long-standing tumor stain with avascular area (s). Correlative evaluation of angiograms, computed tomograms, and pathologic specimens revealed hemorrhage, central necrosis, and cystic degeneration for the avascular area (s) of the tumor stains on the angiograms. The more prominent those secondary changes, the less characteristic the angiographic features.

  15. Assessment of Computer Technology Availability, Accessibility and Usage by Agricultural Education Student Teachers in Secondary Schools in Botswana

    Science.gov (United States)

    Hulela, K.; Rammolai, M.; Mpatane, W.

    2014-01-01

    This study examines the availability, accessibility and usability of computer as a form of information and communication technologies (ICTs) by student teachers in secondary schools. 44 out of 51 student teachers of Agriculture responded to the questionnaire. Means and percentages were used to analyze the data to establish the availability,…

  16. 36 CFR 1254.32 - What rules apply to public access use of the Internet on NARA-supplied computers?

    Science.gov (United States)

    2010-07-01

    ... access use of the Internet on NARA-supplied computers? 1254.32 Section 1254.32 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION PUBLIC AVAILABILITY AND USE USING RECORDS AND DONATED... for Internet use in all NARA research rooms. The number of workstations varies per location. We...

  17. Examining Stakeholder Perceptions of Accessibility and Utilization of Computer and Internet Technology in the Selinsgrove Area School District

    Science.gov (United States)

    Krause, Lorinda M.

    2014-01-01

    This study utilized a mixed methods approach to examine the issue of how parents, students, and teachers (stakeholders) perceive accessibility and the utilization of computer and Internet technology within the Selinsgrove, Pennsylvania Area School District. Quantitative data was collected through the use of questionnaires distributed to the…

  18. A Survey of Exemplar Teachers' Perceptions, Use, and Access of Computer-Based Games and Technology for Classroom Instruction

    Science.gov (United States)

    Proctor, Michael D.; Marks, Yaela

    2013-01-01

    This research reports and analyzes for archival purposes surveyed perceptions, use, and access by 259 United States based exemplar Primary and Secondary educators of computer-based games and technology for classroom instruction. Participating respondents were considered exemplary as they each won the Milken Educator Award during the 1996-2009…

  19. A Parallel Approach in Computing Correlation Immunity up to Six Variables

    Science.gov (United States)

    2015-07-24

    failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE 23 JUL 2015 2. REPORT TYPE...second step, we specify that a condition hold across all assignments of values to the variables chosen in the first step. For pedagogical reasons, we could...table of the function whose correlation immunity is currently being computed. When this circuit is used in exhaustive enumeration, the Function

  20. Correlation of computed tomography, sonography, and gross anatomy of the liver

    International Nuclear Information System (INIS)

    Sexton, C.F.; Zeman, R.K.

    1983-01-01

    Although the vascular and segmental anatomy of the liver is well defined in the sonographic and computed tomographic (CT) literature, the three-dimensional relations of hepatic structures remain conceptually complex. As an aid to understanding and teaching this anatomy, axially and sagitally sectioned gross liver specimens were correlated with appropriate sonographic and CT scans. Major hepatic landmarks and vascular structures are used to identify four distinct transverse planes and four sagittal planes

  1. Implementation of the Two-Point Angular Correlation Function on a High-Performance Reconfigurable Computer

    Directory of Open Access Journals (Sweden)

    Volodymyr V. Kindratenko

    2009-01-01

    Full Text Available We present a parallel implementation of an algorithm for calculating the two-point angular correlation function as applied in the field of computational cosmology. The algorithm has been specifically developed for a reconfigurable computer. Our implementation utilizes a microprocessor and two reconfigurable processors on a dual-MAP SRC-6 system. The two reconfigurable processors are used as two application-specific co-processors. Two independent computational kernels are simultaneously executed on the reconfigurable processors while data pre-fetching from disk and initial data pre-processing are executed on the microprocessor. The overall end-to-end algorithm execution speedup achieved by this implementation is over 90× as compared to a sequential implementation of the algorithm executed on a single 2.8 GHz Intel Xeon microprocessor.

  2. Experiences of registered nurses with regard to accessing health information at the point-of-care via mobile computing devices

    Directory of Open Access Journals (Sweden)

    Esmeralda Ricks

    2015-11-01

    Full Text Available Background: The volume of health information necessary to provide competent health care today has become overwhelming. Mobile computing devices are fast becoming an essential clinical tool for accessing health information at the point-of-care of patients. Objectives: This study explored and described how registered nurses experienced accessing information at the point-of-care via mobile computing devices (MCDs. Method: A qualitative, exploratory, descriptive and contextual design was used. Ten in–depth interviews were conducted with purposively sampled registered nurses employed by a state hospital in the Nelson Mandela Bay Municipality (NMBM. Interviews were recorded, transcribed verbatim and analysed using Tesch’s data analysis technique. Ethical principles were adhered to throughout the study. Guba’s model of trustworthiness was used to confirm integrity of the study. Results: Four themes emerged which revealed that the registered nurses benefited from the training they received by enabling them to develop, and improve, their computer literacy levels. Emphasis was placed on the benefits that the accessed information had for educational purposes for patients and the public, for colleagues and students. Furthermore the ability to access information at the point-of-care was considered by registered nurses as valuable to improve patient care because of the wide range of accurate and readily accessible information available via the mobile computing device. Conclusion: The registered nurses in this study felt that being able to access information at the point-of-care increased their confidence and facilitated the provision of quality care because it assisted them in being accurate and sure of what they were doing.

  3. DiFX: A software correlator for very long baseline interferometry using multi-processor computing environments

    OpenAIRE

    Deller, A. T.; Tingay, S. J.; Bailes, M.; West, C.

    2007-01-01

    We describe the development of an FX style correlator for Very Long Baseline Interferometry (VLBI), implemented in software and intended to run in multi-processor computing environments, such as large clusters of commodity machines (Beowulf clusters) or computers specifically designed for high performance computing, such as multi-processor shared-memory machines. We outline the scientific and practical benefits for VLBI correlation, these chiefly being due to the inherent flexibility of softw...

  4. Respiratory impedance is correlated with airway narrowing in asthma using three-dimensional computed tomography.

    Science.gov (United States)

    Karayama, M; Inui, N; Mori, K; Kono, M; Hozumi, H; Suzuki, Y; Furuhashi, K; Hashimoto, D; Enomoto, N; Fujisawa, T; Nakamura, Y; Watanabe, H; Suda, T

    2018-03-01

    Respiratory impedance comprises the resistance and reactance of the respiratory system and can provide detailed information on respiratory function. However, details of the relationship between impedance and morphological airway changes in asthma are unknown. We aimed to evaluate the correlation between imaging-based airway changes and respiratory impedance in patients with asthma. Respiratory impedance and spirometric data were evaluated in 72 patients with asthma and 29 reference subjects. We measured the intraluminal area (Ai) and wall thickness (WT) of third- to sixth-generation bronchi using three-dimensional computed tomographic analyses, and values were adjusted by body surface area (BSA, Ai/BSA, and WT/the square root (√) of BSA). Asthma patients had significantly increased respiratory impedance, decreased Ai/BSA, and increased WT/√BSA, as was the case in those without airflow limitation as assessed by spirometry. Ai/BSA was inversely correlated with respiratory resistance at 5 Hz (R5) and 20 Hz (R20). R20 had a stronger correlation with Ai/BSA than did R5. Ai/BSA was positively correlated with forced expiratory volume in 1 second/forced vital capacity ratio, percentage predicted forced expiratory volume in 1 second, and percentage predicted mid-expiratory flow. WT/√BSA had no significant correlation with spirometry or respiratory impedance. Respiratory resistance is associated with airway narrowing. © 2018 John Wiley & Sons Ltd.

  5. Correlation of pulmonary function and usual interstitial pneumonia computed tomography patterns in idiopathic pulmonary fibrosis.

    Science.gov (United States)

    Arcadu, Antonella; Byrne, Suzanne C; Pirina, Pietro; Hartman, Thomas E; Bartholmai, Brian J; Moua, Teng

    2017-08-01

    Little is known about presenting 'inconsistent' or 'possible' usual interstitial pneumonia (UIP) computed tomography (CT) patterns advancing to 'consistent' UIP as disease progresses in idiopathic pulmonary fibrosis (IPF). We hypothesized that if 'consistent' UIP represented more advanced disease, such a pattern on presentation should also correlate with more severe pulmonary function test (PFT) abnormalities. Consecutive IPF patients (2005-2013) diagnosed by international criteria with baseline PFT and CT were included. Presenting CTs were assessed by three expert radiologists for consensus UIP pattern ('consistent', 'possible', and 'inconsistent'). Approximation of individual and combined interstitial abnormalities was also performed with correlation of interstitial abnormalities and UIP CT pattern made with PFT findings and survival. Three-hundred and fifty patients (70% male) were included with a mean age of 68.3 years. Mean percent predicted forced vital capacity (FVC%) and diffusion capacity (DLCO%) was 64% and 45.5% respectively. Older age and male gender correlated more with 'consistent' UIP CT pattern. FVC% was not associated with any UIP pattern but did correlate with total volume of radiologist assessed interstitial abnormalities. DLCO% was lower in those with 'consistent' UIP pattern. A 'consistent' UIP CT pattern was also not independently predictive of survival after correction for age, gender, FVC%, and DLCO%. PFT findings appear to correlate with extent of radiologic disease but not specific morphologic patterns. Whether such UIP patterns represent different stages of disease severity or radiologic progression is not supported by coinciding pulmonary function decline. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Spatial correlations in intense ionospheric scintillations - comparison between numerical computation and observation

    International Nuclear Information System (INIS)

    Kumagai, H.

    1987-01-01

    The spatial correlations in intense ionospheric scintillations were analyzed by comparing numerical results with observational ones. The observational results were obtained by spaced-receiver scintillation measurements of VHF satellite radiowave. The numerical computation was made by using the fourth-order moment equation with fairly realistic ionospheric irregularity models, in which power-law irregularities with spectral index 4, both thin and thick slabs, and both isotropic and anisotropic irregularities, were considered. Evolution of the S(4) index and the transverse correlation function was computed. The numerical result that the transverse correlation distance decreases with the increase in S(4) was consistent with that obtained in the observation, suggesting that multiple scattering plays an important role in the intense scintillations observed. The anisotropy of irregularities proved to act as if the density fluctuation increased. This effect, as well as the effect of slab thickness, was evaluated by the total phase fluctuations that the radiowave experienced in the slab. On the basis of the comparison, the irregularity height and electron-density fluctuation which is necessary to produce a particular strength of scintillation were estimated. 30 references

  7. Internet Use and Access Among Pregnant Women via Computer and Mobile Phone: Implications for Delivery of Perinatal Care.

    Science.gov (United States)

    Peragallo Urrutia, Rachel; Berger, Alexander A; Ivins, Amber A; Beckham, A Jenna; Thorp, John M; Nicholson, Wanda K

    2015-03-30

    The use of Internet-based behavioral programs may be an efficient, flexible method to enhance prenatal care and improve pregnancy outcomes. There are few data about access to, and use of, the Internet via computers and mobile phones among pregnant women. We describe pregnant women's access to, and use of, computers, mobile phones, and computer technologies (eg, Internet, blogs, chat rooms) in a southern United States population. We describe the willingness of pregnant women to participate in Internet-supported weight-loss interventions delivered via computers or mobile phones. We conducted a cross-sectional survey among 100 pregnant women at a tertiary referral center ultrasound clinic in the southeast United States. Data were analyzed using Stata version 10 (StataCorp) and R (R Core Team 2013). Means and frequency procedures were used to describe demographic characteristics, access to computers and mobile phones, and use of specific Internet modalities. Chi-square testing was used to determine whether there were differences in technology access and Internet modality use according to age, race/ethnicity, income, or children in the home. The Fisher's exact test was used to describe preferences to participate in Internet-based postpartum weight-loss interventions via computer versus mobile phone. Logistic regression was used to determine demographic characteristics associated with these preferences. The study sample was 61.0% white, 26.0% black, 6.0% Hispanic, and 7.0% Asian with a mean age of 31.0 (SD 5.1). Most participants had access to a computer (89/100, 89.0%) or mobile phone (88/100, 88.0%) for at least 8 hours per week. Access remained high (>74%) across age groups, racial/ethnic groups, income levels, and number of children in the home. Internet/Web (94/100, 94.0%), email (90/100, 90.0%), and Facebook (50/100, 50.0%) were the most commonly used Internet technologies. Women aged less than 30 years were more likely to report use of Twitter and chat rooms

  8. Internet Use and Access Among Pregnant Women via Computer and Mobile Phone: Implications for Delivery of Perinatal Care

    Science.gov (United States)

    Peragallo Urrutia, Rachel; Berger, Alexander A; Ivins, Amber A; Beckham, A Jenna; Thorp Jr, John M

    2015-01-01

    Background The use of Internet-based behavioral programs may be an efficient, flexible method to enhance prenatal care and improve pregnancy outcomes. There are few data about access to, and use of, the Internet via computers and mobile phones among pregnant women. Objective We describe pregnant women’s access to, and use of, computers, mobile phones, and computer technologies (eg, Internet, blogs, chat rooms) in a southern United States population. We describe the willingness of pregnant women to participate in Internet-supported weight-loss interventions delivered via computers or mobile phones. Methods We conducted a cross-sectional survey among 100 pregnant women at a tertiary referral center ultrasound clinic in the southeast United States. Data were analyzed using Stata version 10 (StataCorp) and R (R Core Team 2013). Means and frequency procedures were used to describe demographic characteristics, access to computers and mobile phones, and use of specific Internet modalities. Chi-square testing was used to determine whether there were differences in technology access and Internet modality use according to age, race/ethnicity, income, or children in the home. The Fisher’s exact test was used to describe preferences to participate in Internet-based postpartum weight-loss interventions via computer versus mobile phone. Logistic regression was used to determine demographic characteristics associated with these preferences. Results The study sample was 61.0% white, 26.0% black, 6.0% Hispanic, and 7.0% Asian with a mean age of 31.0 (SD 5.1). Most participants had access to a computer (89/100, 89.0%) or mobile phone (88/100, 88.0%) for at least 8 hours per week. Access remained high (>74%) across age groups, racial/ethnic groups, income levels, and number of children in the home. Internet/Web (94/100, 94.0%), email (90/100, 90.0%), and Facebook (50/100, 50.0%) were the most commonly used Internet technologies. Women aged less than 30 years were more likely to

  9. Computed tomography, lymphography, and staging laparotomy: correlations in initial staging of Hodgkin disease

    Energy Technology Data Exchange (ETDEWEB)

    Castellino, R.A.; Hoppe, R.T.; Blank, N.; Young, S.W.; Neumann, C.; Rosenberg, S.A.; Kaplan, H.S.

    1984-07-01

    One hundred twenty-one patients with newly diagnosed, previously untreated Hodgkin disease underwent abdominal and pelvic computed tomographic (CT) scanning and bipedal lymphography. These studies were followed by staging laparotomy, which included biopsy of the liver, retroperitoneal and mesenteric lymph nodes, and splenectomy. Correlation of the results of the imaging studies with the histopathologic diagnoses revealed a small - but significant - increased accuracy of lymphography compared with CT in assessing the retroperitoneal lymph nodes. The theoretical advantages of CT scanning in detecting lymphomatous deposits in lymph nodes about the celiac axis and the mesentery, or in the liver and spleen, were not confirmed.

  10. Analytical Computation of Energy-Energy Correlation at Next-to-Leading Order in QCD.

    Science.gov (United States)

    Dixon, Lance J; Luo, Ming-Xing; Shtabovenko, Vladyslav; Yang, Tong-Zhi; Zhu, Hua Xing

    2018-03-09

    The energy-energy correlation (EEC) between two detectors in e^{+}e^{-} annihilation was computed analytically at leading order in QCD almost 40 years ago, and numerically at next-to-leading order (NLO) starting in the 1980s. We present the first analytical result for the EEC at NLO, which is remarkably simple, and facilitates analytical study of the perturbative structure of the EEC. We provide the expansion of the EEC in the collinear and back-to-back regions through next-to-leading power, information which should aid resummation in these regions.

  11. Air trapping in sarcoidosis on computed tomography: Correlation with lung function

    International Nuclear Information System (INIS)

    Davies, C.W.H.; Tasker, A.D.; Padley, S.P.G.; Davies, R.J.O.; Gleeson, F.V.

    2000-01-01

    AIMS: To document the presence and extent of air trapping on high resolution computed tomography (HRCT) in patients with pulmonary sarcoidosis and correlate HRCT features with pulmonary function tests. METHODS: Twenty-one patients with pulmonary sarcoidosis underwent HRCT and pulmonary function assessment at presentation. Inspiratory and expiratory HRCT were assessed for the presence and extent of air trapping, ground-glass opacification, nodularity, septal thickening, bronchiectasis and parenchymal distortion. HRCT features were correlated with pulmonary function tests. RESULTS: Air trapping on expiratory HRCT was present in 20/21 (95%) patients. The extent of air trapping correlated with percentage predicted residual volume (RV)/total lung capacity (TLC) (r = 0.499;P < 0.05) and percentage predicted maximal mid-expiratory flow rate between 25 and 75% of the vital capacity (r = -0.54;P < 0.05). Ground-glass opacification was present in four of 21 (19%), nodularity in 18/21 (86%), septal thickening in 18/21 (86%), traction bronchiectasis in 14/21 (67%) and distortion in 12/21 (57%) of patients; there were no significant relationships between these CT features and pulmonary function results. CONCLUSION: Air trapping is a common feature in sarcoidosis and correlates with evidence of small airways disease on pulmonary function testing. Davies, C.W.H. (2000). Clinical Radiology 55, 217-221

  12. Pulmonary arteriovenous malformations in hereditary haemorrhagic telangiectasia. Correlations between computed tomography findings and cerebral complications

    Energy Technology Data Exchange (ETDEWEB)

    Etievant, Johan; Si-Mohamed, Salim; Vinurel, Nicolas; Revel, Didier [Hospices Civils de Lyon, Hopital Cardiologique Louis Pradel, Departement d' Imagerie Cardiaque et Thoracique, Diagnostique et Interventionnelle, Bron (France); Universite Claude Bernard Lyon 1, Villeurbanne (France); Dupuis-Girod, Sophie [Hospices Civils de Lyon, Hopital Femme-Mere-Enfant, Service de Genetique, Centre de Reference pour la maladie de Rendu-Osler, Lyon (France); Decullier, Evelyne [Universite Claude Bernard Lyon 1, Villeurbanne (France); Hospices Civils de Lyon, Pole Information Medicale Evaluation Recherche, Lyon (France); Gamondes, Delphine [Hospices Civils de Lyon, Hopital Cardiologique Louis Pradel, Departement d' Imagerie Cardiaque et Thoracique, Diagnostique et Interventionnelle, Bron (France); Khouatra, Chahera [Hospices Civils de Lyon, Hopital Cardiologique Louis Pradel, Service de pneumologie - Centre des Maladies Orphelines Pulmonaires, Lyon (France); Cottin, Vincent [Universite Claude Bernard Lyon 1, Villeurbanne (France); Hospices Civils de Lyon, Hopital Cardiologique Louis Pradel, Service de pneumologie - Centre des Maladies Orphelines Pulmonaires, Lyon (France)

    2018-03-15

    Computed tomography (CT) is the modality of choice to characterise pulmonary arteriovenous malformations (PAVMs) in patients with hereditary haemorrhagic telangiectasia (HHT). Our objective was to determine if CT findings were associated with frequency of brain abscess and ischaemic stroke. This retrospective study included patients with HHT-related PAVMs. CT results, i.e. PAVM presentation (unique, multiple, disseminated or diffuse), the number of PAVMs and the largest feeding artery size, were correlated to prevalence of ischaemic stroke and brain abscess. All CTs were reviewed in consensus by two radiologists. Of 170 patients, 73 patients had unique (42.9 %), 49 multiple (28.8 %), 36 disseminated (21.2 %) and 12 diffuse (7.1 %) PAVMs. Fifteen patients presented with brain abscess; 26 patients presented with ischaemic stroke. The number of PAVMs was significantly correlated with brain abscess (11.5 vs. 6.2, respectively; p=0.025). The mean diameter of the largest feeding artery was significantly correlated with ischaemic stroke frequency (4.9 vs. 3.2 mm, respectively; p=0.0098). The number of PAVMs correlated significantly with risk of brain abscess, and a larger feeding artery significantly with more ischaemic strokes. These findings can lead to a better recognition and management of the PAVMs at risk of cerebral complications. (orig.)

  13. Overdiagnosing of femoroacetabular impingement: correlation between clinical presentation and computed tomography in symptomatic patients☆

    Science.gov (United States)

    Canella, Richard Prazeres; Adam, Guilherme Pradi; de Castillo, Roberto André Ulhôa; Codonho, Daniel; Ganev, Gerson Gandhi; de Vicenzi, Luiz Fernando

    2016-01-01

    Objective To correlate the angles between the acetabulum and the proximal femur in symptomatic patients with femoroacetabular impingement (FAI), using computed tomography (CT). Methods We retrospectively evaluated 103 hips from 103 patients, using multislice CT to measure the acetabular age, acetabular version (in its supraequatorial portion and in its middle third), femoral neck version, cervical-diaphyseal and alpha angles and the acetabular depth. For the statistical analysis, we used the Pearson correlation coefficient. Results There were inverse correlations between the following angles: (1) acetabular coverage versus alpha angle (p = 0.019); (2) acetabular version (supraequatorial) versus alpha angle (p = 0.049). For patients with femoral anteversion lower than 15 degrees: (1) acetabular version (supraequatorial) versus alpha angle (p = 0.026); (2) acetabular version (middle third) versus alpha angle (p = 0.02). For patients with acetabular version (supraequatorial) lower than 10 degrees: (1) acetabular version (supraequatorial) versus alpha angle (p = 0.004); (2) acetabular version (middle third) versus alpha angle (p = 0.009). Conclusion There was a statistically significant inverse correlation between the acetabular version and alpha angles (the smaller the acetabular anteversion angle was, the larger the alpha angle was) in symptomatic patients, thus supporting the hypothesis that FAI occurs when cam and pincer findings due to acetabular retroversion are seen simultaneously, and that the latter alone does not cause FAI, which leads to overdiagnosis in these cases. PMID:27069890

  14. Research on Quantum Authentication Methods for the Secure Access Control Among Three Elements of Cloud Computing

    Science.gov (United States)

    Dong, Yumin; Xiao, Shufen; Ma, Hongyang; Chen, Libo

    2016-12-01

    Cloud computing and big data have become the developing engine of current information technology (IT) as a result of the rapid development of IT. However, security protection has become increasingly important for cloud computing and big data, and has become a problem that must be solved to develop cloud computing. The theft of identity authentication information remains a serious threat to the security of cloud computing. In this process, attackers intrude into cloud computing services through identity authentication information, thereby threatening the security of data from multiple perspectives. Therefore, this study proposes a model for cloud computing protection and management based on quantum authentication, introduces the principle of quantum authentication, and deduces the quantum authentication process. In theory, quantum authentication technology can be applied in cloud computing for security protection. This technology cannot be cloned; thus, it is more secure and reliable than classical methods.

  15. 3D fast adaptive correlation imaging for large-scale gravity data based on GPU computation

    Science.gov (United States)

    Chen, Z.; Meng, X.; Guo, L.; Liu, G.

    2011-12-01

    In recent years, large scale gravity data sets have been collected and employed to enhance gravity problem-solving abilities of tectonics studies in China. Aiming at the large scale data and the requirement of rapid interpretation, previous authors have carried out a lot of work, including the fast gradient module inversion and Euler deconvolution depth inversion ,3-D physical property inversion using stochastic subspaces and equivalent storage, fast inversion using wavelet transforms and a logarithmic barrier method. So it can be say that 3-D gravity inversion has been greatly improved in the last decade. Many authors added many different kinds of priori information and constraints to deal with nonuniqueness using models composed of a large number of contiguous cells of unknown property and obtained good results. However, due to long computation time, instability and other shortcomings, 3-D physical property inversion has not been widely applied to large-scale data yet. In order to achieve 3-D interpretation with high efficiency and precision for geological and ore bodies and obtain their subsurface distribution, there is an urgent need to find a fast and efficient inversion method for large scale gravity data. As an entirely new geophysical inversion method, 3D correlation has a rapid development thanks to the advantage of requiring no a priori information and demanding small amount of computer memory. This method was proposed to image the distribution of equivalent excess masses of anomalous geological bodies with high resolution both longitudinally and transversely. In order to tranform the equivalence excess masses into real density contrasts, we adopt the adaptive correlation imaging for gravity data. After each 3D correlation imaging, we change the equivalence into density contrasts according to the linear relationship, and then carry out forward gravity calculation for each rectangle cells. Next, we compare the forward gravity data with real data, and

  16. Big Data solutions on a small scale: Evaluating accessible high-performance computing for social research

    OpenAIRE

    Murthy, Dhiraj; Bowman, S. A.

    2014-01-01

    Though full of promise, Big Data research success is often contingent on access to the newest, most advanced, and often expensive hardware systems and the expertise needed to build and implement such systems. As a result, the accessibility of the growing number of Big Data-capable technology solutions has often been the preserve of business analytics. Pay as you store/process services like Amazon Web Services have opened up possibilities for smaller scale Big Data projects. There is high dema...

  17. Image-Guided Radiotherapy for Liver Cancer Using Respiratory-Correlated Computed Tomography and Cone-Beam Computed Tomography

    International Nuclear Information System (INIS)

    Guckenberger, Matthias; Sweeney, Reinhart A.; Wilbert, Juergen; Krieger, Thomas; Richter, Anne; Baier, Kurt; Mueller, Gerd; Sauer, Otto; Flentje, Michael

    2008-01-01

    Purpose: To evaluate a novel four-dimensional (4D) image-guided radiotherapy (IGRT) technique in stereotactic body RT for liver tumors. Methods and Materials: For 11 patients with 13 intrahepatic tumors, a respiratory-correlated 4D computed tomography (CT) scan was acquired at treatment planning. The target was defined using CT series reconstructed at end-inhalation and end-exhalation. The liver was delineated on these two CT series and served as a reference for image guidance. A cone-beam CT scan was acquired after patient positioning; the blurred diaphragm dome was interpreted as a probability density function showing the motion range of the liver. Manual contour matching of the liver structures from the planning 4D CT scan with the cone-beam CT scan was performed. Inter- and intrafractional uncertainties of target position and motion range were evaluated, and interobserver variability of the 4D-IGRT technique was tested. Results: The workflow of 4D-IGRT was successfully practiced in all patients. The absolute error in the liver position and error in relation to the bony anatomy was 8 ± 4 mm and 5 ± 2 mm (three-dimensional vector), respectively. Margins of 4-6 mm were calculated for compensation of the intrafractional drifts of the liver. The motion range of the diaphragm dome was reproducible within 5 mm for 11 of 13 lesions, and the interobserver variability of the 4D-IGRT technique was small (standard deviation, 1.5 mm). In 4 patients, the position of the intrahepatic lesion was directly verified using a mobile in-room CT scanner after application of intravenous contrast. Conclusion: The results of our study have shown that 4D image guidance using liver contour matching between respiratory-correlated CT and cone-beam CT scans increased the accuracy compared with stereotactic positioning and compared with IGRT without consideration of breathing motion

  18. Increasing the computational efficient of digital cross correlation by a vectorization method

    Science.gov (United States)

    Chang, Ching-Yuan; Ma, Chien-Ching

    2017-08-01

    This study presents a vectorization method for use in MATLAB programming aimed at increasing the computational efficiency of digital cross correlation in sound and images, resulting in a speedup of 6.387 and 36.044 times compared with performance values obtained from looped expression. This work bridges the gap between matrix operations and loop iteration, preserving flexibility and efficiency in program testing. This paper uses numerical simulation to verify the speedup of the proposed vectorization method as well as experiments to measure the quantitative transient displacement response subjected to dynamic impact loading. The experiment involved the use of a high speed camera as well as a fiber optic system to measure the transient displacement in a cantilever beam under impact from a steel ball. Experimental measurement data obtained from the two methods are in excellent agreement in both the time and frequency domain, with discrepancies of only 0.68%. Numerical and experiment results demonstrate the efficacy of the proposed vectorization method with regard to computational speed in signal processing and high precision in the correlation algorithm. We also present the source code with which to build MATLAB-executable functions on Windows as well as Linux platforms, and provide a series of examples to demonstrate the application of the proposed vectorization method.

  19. Ground-glass opacity in diffuse lung diseases: high-resolution computed tomography-pathology correlation

    International Nuclear Information System (INIS)

    Santos, Maria Lucia de Oliveira; Vianna, Alberto Domingues; Marchiori, Edson; Souza Junior, Arthur Soares; Moraes, Heleno Pinto de

    2003-01-01

    Ground-glass opacity is a finding frequently seen in high-resolution computed tomography examinations of the chest and is characterized by hazy increased attenuation of lung, however without blurring of bronchial and vascular margins. Due to its un specificity, association with other radiological, clinical and pathological findings must be considered for an accurate diagnostic interpretation. In this paper were reviewed 62 computed tomography examinations of patients with diffuse pulmonary diseases of 14 different etiologies in which ground-glass opacity was the only or the most remarkable finding, and correlated this findings with pathology abnormalities seen on specimens obtained from biopsies or necropsies. In pneumocystosis, ground-glass opacities correlated histologically with alveolar occupation by a foaming material containing parasites, in bronchiole alveolar cell carcinoma with thickening of the alveolar septa and occupation of the lumen by mucus and tumoral cells, in paracoccidioidomycosis with thickening of the alveolar septa, areas of fibrosis and alveolar bronchopneumonia exudate, in sarcoidosis with fibrosis or clustering of granulomas and in idiopathic pulmonary fibrosis with alveolar septa thickening due to fibrosis. Alveolar occupation by blood was found in cases of leptospirosis, idiopathic hemo siderosis, metastatic kidney tumor and invasive aspergillosis whereas oily vacuole were seen in lipoid pneumonia, proteinaceous and lipo proteinaceous material in silico proteinosis and pulmonary alveolar proteinosis, and edematous fluid in cardiac failure. (author)

  20. Soft-error tolerance and energy consumption evaluation of embedded computer with magnetic random access memory in practical systems using computer simulations

    Science.gov (United States)

    Nebashi, Ryusuke; Sakimura, Noboru; Sugibayashi, Tadahiko

    2017-08-01

    We evaluated the soft-error tolerance and energy consumption of an embedded computer with magnetic random access memory (MRAM) using two computer simulators. One is a central processing unit (CPU) simulator of a typical embedded computer system. We simulated the radiation-induced single-event-upset (SEU) probability in a spin-transfer-torque MRAM cell and also the failure rate of a typical embedded computer due to its main memory SEU error. The other is a delay tolerant network (DTN) system simulator. It simulates the power dissipation of wireless sensor network nodes of the system using a revised CPU simulator and a network simulator. We demonstrated that the SEU effect on the embedded computer with 1 Gbit MRAM-based working memory is less than 1 failure in time (FIT). We also demonstrated that the energy consumption of the DTN sensor node with MRAM-based working memory can be reduced to 1/11. These results indicate that MRAM-based working memory enhances the disaster tolerance of embedded computers.

  1. Nephrocalcinosis in rabbits - correlation of ultrasound, computed tomography, pathology and renal function

    International Nuclear Information System (INIS)

    Cramer, B.; Pushpanathan, C.

    1998-01-01

    Objective. The purpose of this study was to induce nephrocalcinosis (NC) in rabbits with phosphate, vitamin D, oxalate and furosemide, to determine the effect of renal function and to correlate detection of ultrasound (US) and computed tomography (CT) with pathology. Materials and methods. Seventy-five immature New Zealand white rabbits were divided into five groups of 15. In each group, 5 animals were controls and 10 were given oral phosphate, furosemide, vitamin D or oxalate, furosemide, vitamin D or oxalate. Unilateral nephrectomy was performed at 3-6 weeks, and 5 rabbits of each test group were withdrawn from the substance. Weekly US was performed as well as US, CT and measurement of serum creatinine at the time of nephrectomy and prior to planned demise. Results. A todal of 140 kidneys in 75 rabbits had both pathological and US correlation, with CT correlation in 126. Forty rabbits developed nephrocalcinosis with early (post nephrectomy at 3-6 weeks) or late (post demise at 10-20 weeks) phatological correlation obtained in 53 kidneys. Forty-one of these kidneys were from test animals: 23 developed NC early, 18 late. Twelve controls developed NC; 4 early, 8 late. Comparing US and CT to phatology, the sensitivity was 96% for US, 64% for CT. Specificity was 85% for US and 96% for CT. In 109 kidneys, information on serum creatinine level was available to correlate with phatology. The mean creatinine level was 138 mmol/l for those with NC and 118 mmol/l for those without NC (P<0.001)

  2. Nephrocalcinosis in rabbits - correlation of ultrasound, computed tomography, pathology and renal function

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, B.; Pushpanathan, C. [Janeway Child Health Centre, St. Johns`s (Canada). Radiology Dept.; Husa, L. [Memorial Univ. of Newfoundland, St. Johns`s (Canada)

    1998-01-01

    Objective. The purpose of this study was to induce nephrocalcinosis (NC) in rabbits with phosphate, vitamin D, oxalate and furosemide, to determine the effect of renal function and to correlate detection of ultrasound (US) and computed tomography (CT) with pathology. Materials and methods. Seventy-five immature New Zealand white rabbits were divided into five groups of 15. In each group, 5 animals were controls and 10 were given oral phosphate, furosemide, vitamin D or oxalate, furosemide, vitamin D or oxalate. Unilateral nephrectomy was performed at 3-6 weeks, and 5 rabbits of each test group were withdrawn from the substance. Weekly US was performed as well as US, CT and measurement of serum creatinine at the time of nephrectomy and prior to planned demise. Results. A todal of 140 kidneys in 75 rabbits had both pathological and US correlation, with CT correlation in 126. Forty rabbits developed nephrocalcinosis with early (post nephrectomy at 3-6 weeks) or late (post demise at 10-20 weeks) phatological correlation obtained in 53 kidneys. Forty-one of these kidneys were from test animals: 23 developed NC early, 18 late. Twelve controls developed NC; 4 early, 8 late. Comparing US and CT to phatology, the sensitivity was 96% for US, 64% for CT. Specificity was 85% for US and 96% for CT. In 109 kidneys, information on serum creatinine level was available to correlate with phatology. The mean creatinine level was 138 mmol/l for those with NC and 118 mmol/l for those without NC (P<0.001).

  3. A Practical Computational Method for the Anisotropic Redshift-Space 3-Point Correlation Function

    Science.gov (United States)

    Slepian, Zachary; Eisenstein, Daniel J.

    2018-04-01

    We present an algorithm enabling computation of the anisotropic redshift-space galaxy 3-point correlation function (3PCF) scaling as N2, with N the number of galaxies. Our previous work showed how to compute the isotropic 3PCF with this scaling by expanding the radially-binned density field around each galaxy in the survey into spherical harmonics and combining these coefficients to form multipole moments. The N2 scaling occurred because this approach never explicitly required the relative angle between a galaxy pair about the primary galaxy. Here we generalize this work, demonstrating that in the presence of azimuthally-symmetric anisotropy produced by redshift-space distortions (RSD) the 3PCF can be described by two triangle side lengths, two independent total angular momenta, and a spin. This basis for the anisotropic 3PCF allows its computation with negligible additional work over the isotropic 3PCF. We also present the covariance matrix of the anisotropic 3PCF measured in this basis. Our algorithm tracks the full 5-D redshift-space 3PCF, uses an accurate line of sight to each triplet, is exact in angle, and easily handles edge correction. It will enable use of the anisotropic large-scale 3PCF as a probe of RSD in current and upcoming large-scale redshift surveys.

  4. High-resolution computed tomography in silicosis: correlation with chest radiography and pulmonary function tests

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Agnaldo Jose [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Pedro Ernesto Univ. Hospital. Dept. of Respiratory Function]. E-mail: phel.lop@uol.com.br; Mogami, Roberto; Capone, Domenico; Jansen, Jose Manoel [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). School of Medical Sciences; Tessarollo, Bernardo [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. of Radiology and Diagnostic Image; Melo, Pedro Lopes de [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. of Biology

    2008-05-15

    Objective: To correlate tomographic findings with pulmonary function findings, as well as to compare chest X-ray findings with high-resolution computed tomography (HRCT) findings, in patients with silicosis. Methods: A cross-sectional study was conducted in 44 non-smoking patients without a history of tuberculosis. Chest X-ray findings were classified according to the International Labour Organization recommendations. Using a semiquantitative system, the following HRCT findings were measured: the full extent of pulmonary involvement; parenchymal opacities; and emphysema. Spirometry and forced oscillation were performed. Pulmonary volumes were evaluated using the helium dilution method, and diffusing capacity of the lung for carbon monoxide was assessed. Results: Of the 44 patients studied, 41 were male. The mean age was 48.4 years. There were 4 patients who were classified as category 0 based on X-ray findings and as category 1 based on HRCT findings. Using HRCT scans, we identified progressive massive fibrosis in 33 patients, compared with only 23 patients when X-rays were used. Opacity score was found to correlate most closely with airflow, DLCO and compliance. Emphysema score correlated inversely with volume, DLCO and airflow. In this sample of patients presenting a predominance of large opacities (75% of the individuals), the deterioration of pulmonary function was associated with the extent of structural changes. Conclusions: In the early detection of silicosis and the identification of progressive massive fibrosis, HRCT scans are superior to X-rays. (author)

  5. High-resolution computed tomography in silicosis: correlation with chest radiography and pulmonary function tests

    International Nuclear Information System (INIS)

    Lopes, Agnaldo Jose; Mogami, Roberto; Capone, Domenico; Jansen, Jose Manoel; Tessarollo, Bernardo; Melo, Pedro Lopes de

    2008-01-01

    Objective: To correlate tomographic findings with pulmonary function findings, as well as to compare chest X-ray findings with high-resolution computed tomography (HRCT) findings, in patients with silicosis. Methods: A cross-sectional study was conducted in 44 non-smoking patients without a history of tuberculosis. Chest X-ray findings were classified according to the International Labour Organization recommendations. Using a semiquantitative system, the following HRCT findings were measured: the full extent of pulmonary involvement; parenchymal opacities; and emphysema. Spirometry and forced oscillation were performed. Pulmonary volumes were evaluated using the helium dilution method, and diffusing capacity of the lung for carbon monoxide was assessed. Results: Of the 44 patients studied, 41 were male. The mean age was 48.4 years. There were 4 patients who were classified as category 0 based on X-ray findings and as category 1 based on HRCT findings. Using HRCT scans, we identified progressive massive fibrosis in 33 patients, compared with only 23 patients when X-rays were used. Opacity score was found to correlate most closely with airflow, DLCO and compliance. Emphysema score correlated inversely with volume, DLCO and airflow. In this sample of patients presenting a predominance of large opacities (75% of the individuals), the deterioration of pulmonary function was associated with the extent of structural changes. Conclusions: In the early detection of silicosis and the identification of progressive massive fibrosis, HRCT scans are superior to X-rays. (author)

  6. Providing disabled persons in developing countries access to computer games through a novel gaming input device

    CSIR Research Space (South Africa)

    Smith, Andrew C

    2011-01-01

    Full Text Available A novel input device is presented for use with a personal computer by persons with physical disabilities who would otherwise not be able to enjoy computer gaming. This device is simple to manufacture and low in cost. A gaming application...

  7. Paraquat-poisoning in the rabbit lungs: high resolution computed tomographic findings and pathologic correlation

    International Nuclear Information System (INIS)

    Lee, Kyung Soo; Kim, Eui Han; Lee, Byoung Ho; Kim, Kun Sang

    1992-01-01

    The authors evaluated high resolution computed tomographic (HRCT) findings of the isolated rabbit lungs with paraquat poisoning, and the findings were correlated with pathologic specimens. The purposes of this study are 1) to obtain the HRCT findings of the normal rabbit lung. 2) to find out if pulmonary pathology can be induced in rabbits by paraquat, and 3) to correlate the HRCT findings to those of pathology. Thirty rabbits were divided into three groups: group I included four control rabbits; group II included 16 rabbits given paraquat intraperitoneally (IP group); and group III included 10 rabbits given paraquat intravenously (IV group). The rabbits were sacrificed seven, 10, and 14 days after injection of various amount of paraquat, and then the lungs were isolated for HRCT and pathologic studies. Gross and microscopic findings of the three groups of control and paraquat-injected rabbit lungs were correlated with HRCT findings. Pulmonary congestion, mild thickening of alveolar walls and septae, and multifocal micro-atelectasis were the man pathologic findings of the lungs in both groups of the rabbits. Pulmonary hemorrhage was noted in five (31%) of 16 rabbits of IP group and three (30%) of 10 IV group. Pulmonary edema was seen in one rabbits (6%) of IP and four (40%) of IV group. Typical pulmonary fibrosis was seen in one rabbit of IP (6%) and IV (10%) group, respectively. There was no correlation between the amount of paraquat and frequency of the pulmonary pathology. Pulmonary fibrosis was seen at least one week after the paraquat injection. On HRCT, pulmonary hemorrhage and edema appeared as diffuse air-space consolidation and pulmonary fibrosis as linear or band-like opacities. However, minimal changes such as mild congestion

  8. Handling of computational in vitro/in vivo correlation problems by Microsoft Excel: I. Principles and some general algorithms.

    Science.gov (United States)

    Langenbucher, Frieder

    2002-01-01

    Most computations in the field of in vitro/in vivo correlations can be handled directly by Excel worksheets, without the need for specialized software. Following a summary of Excel features, applications are illustrated for numerical computation of AUC and Mean, Wagner-Nelson and Loo-Riegelman absorption plots, and polyexponential curve fitting.

  9. Use of Tablet Computers to Improve Access to Education in a Remote Location

    Science.gov (United States)

    Ally, Mohamed; Balaji, V.; Abdelbaki, Anwar; Cheng, Ricky

    2017-01-01

    A research project was carried out in using mobile learning to increase access to education. This project is contributing to the achievement of Goal 4 of the Sustainable Development Goals (SDGs), which is to "Ensure inclusive and equitable quality education and promote lifelong learning opportunities for all". The mobile learning project…

  10. Novel Kinds of Random Access Memory and New Vulnerabilities of Computer Aids based on Them

    Directory of Open Access Journals (Sweden)

    Alexander Mihaylovich Korotin

    2014-09-01

    Full Text Available The article discusses vulnerabilities of computer aids based on existing RAM and mechanisms for restricting exploitation of such vulnerabilities. In addition, the article discusses features and work methods of different RAM.

  11. Correlation between computed tomographic and magnetic resonance imaging findings of parenchymal lung diseases

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, Miriam Menna; Rafful, Patricia Piazza [Department of Radiology, Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); Rodrigues, Rosana Souza [Department of Radiology, Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); D’Or Institute for Research and Education, Rio de Janeiro, RJ (Brazil); Zanetti, Gláucia [Department of Radiology, Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); Hochhegger, Bruno [Complexo Hospitalar Santa Casa de Misericórdia de Porto Alegre, Porto Alegre, RS (Brazil); Souza, Arthur Soares [Department of Radiology, Medical School of Rio Preto (FAMERP) and Ultra X, São José do Rio Preto, SP (Brazil); Guimarães, Marcos Duarte [Department of Imaging, Hospital AC Camargo, São Paulo, SP (Brazil); Marchiori, Edson, E-mail: edmarchiori@gmail.com [Department of Radiology, Federal University of Rio de Janeiro, Rio de Janeiro (Brazil)

    2013-09-15

    Computed tomography (CT) is considered to be the gold standard method for the assessment of morphological changes in the pulmonary parenchyma. Although its spatial resolution is lower than that of CT, MRI offers the advantage of characterizing different aspects of tissue based on the degree of contrast on T1-weighted image (WI) and T2-WI. In this article, we describe and correlate the MRI and CT features of several common patterns of parenchymal lung disease (air trapping, atelectasis, bronchiectasis, cavitation, consolidation, emphysema, ground-glass opacities, halo sign, interlobular septal thickening, masses, mycetoma, nodules, progressive massive fibrosis, reverse halo sign and tree-in-bud pattern). MRI may be an alternative modality for the collection of morphological and functional information useful for the management of parenchymal lung disease, which would help reduce the number of chest CT scans and radiation exposure required in patients with a variety of conditions.

  12. Recent Progress in First-Principles Methods for Computing the Electronic Structure of Correlated Materials

    Directory of Open Access Journals (Sweden)

    Fredrik Nilsson

    2018-03-01

    Full Text Available Substantial progress has been achieved in the last couple of decades in computing the electronic structure of correlated materials from first principles. This progress has been driven by parallel development in theory and numerical algorithms. Theoretical development in combining ab initio approaches and many-body methods is particularly promising. A crucial role is also played by a systematic method for deriving a low-energy model, which bridges the gap between real and model systems. In this article, an overview is given tracing the development from the LDA+U to the latest progress in combining the G W method and (extended dynamical mean-field theory ( G W +EDMFT. The emphasis is on conceptual and theoretical aspects rather than technical ones.

  13. Neuropathological correlations with the computed tomograms in Creutzfeldt-Jakob disease

    Energy Technology Data Exchange (ETDEWEB)

    Nagura, Hiroshi; Tohgi, Hideo; Yamanouchi, Hiroshi (Tokyo Metropolitan Geriatric Medical Center (Japan)); Tomonaga, Masanori

    1983-03-01

    Findings of computed tomograms were correlated with pathological changes in 3 autopsied cases of Creutzfeldt-Jakob disease who died at various stages of the disease. CTs were almost normal at the periods when severe dementia, myoclonus fully developed. The brain from a patient who died at this period showed slight nerve cell loss and spongiform changes mainly in the cerebral cortex. CTs of two advanced cases showed that the atrophic processes of the brain progressed rapidly. In these cases severe nerve cell loss and status spongiosus were found in the cerebral cortex, basal nuclei and cerebellum. Serial CTs showed that atrophic processes involved first the cerebral cortex, and then the basal nuclei and cerebellum. These observations pose the problem whether the difference in the distribution of lesions observed in cases of Creutzfeldt-Jakob disease is merely due to the different stages of the disease at the time of death or due to the variety of pathologic processes in individual case.

  14. Neuropathological correlations with the computed tomograms in Creutzfeldt-Jakob disease

    International Nuclear Information System (INIS)

    Nagura, Hiroshi; Tohgi, Hideo; Yamanouchi, Hiroshi; Tomonaga, Masanori.

    1983-01-01

    Findings of computed tomograms were correlated with pathological changes in 3 autopsied cases of Creutzfeldt-Jakob disease who died at various stages of the disease. CTs were almost normal at the periods when severe dementia, myoclonus fully developed. The brain from a patient who died at this period showed slight nerve cell loss and spongiform changes mainly in the cerebral cortex. CTs of two advanced cases showed that the atrophic processes of the brain progressed rapidly. In these cases severe nerve cell loss and status spongiosus were found in the cerebral cortex, basal nuclei and cerebellum. Serial CTs showed that atrophic processes involved first the cerebral cortex, and then the basal nuclei and cerebellum. These observations pose the problem whether the difference in the distribution of lesions observed in cases of Creutzfeldt-Jakob disease is merely due to the different stages of the disease at the time of death or due to the variety of pathologic processes in individual case. (author)

  15. Computed tomography of the anterior mediastinum in myasthemia gravis: a radiologic-pathologic correlative study

    Energy Technology Data Exchange (ETDEWEB)

    Fon, G.T.; Bein, M.E.; Mancuso, A.A.; Keesey, J.C.; Lupetin, A.R.; Wong, W.S.

    1982-01-01

    Chest radiographs and computed tomographic (CT) scans of the mediastinum were correlated with pathologic findings of the thymus following thymectomy in 57 patients with myasthenia gravis. Based on the patient's age and the overall morphology of the anterior mediastinum, CT scans were assigned one of four grades in an attempt to predict thymus pathologic findings. Using this grading, 14 of 16 cases of thymoma were suspected or definitely diagnosed. One of the two cases not diagnosed on CT was a microscopic tumor. There were no false-positive diagnoses in 11 cases graded as definitely thymoma. We conclude that thymoma can be sensitively diagnosed in patients older than 40 years of age. However, thymoma cannot be predicted with a high level of confidence in patients younger than 40 because of the difficulty in differentiating normal thymus or hyperplasia from thymoma. Recommendations for the use of CT in the preoperative evaluation of myasthenic patients are presented.

  16. Computed tomography of the anterior mediastinum in myasthemia gravis: a radiologic-pathologic correlative study

    International Nuclear Information System (INIS)

    Fon, G.T.; Bein, M.E.; Mancuso, A.A.; Keesey, J.C.; Lupetin, A.R.; Wong, W.S.

    1982-01-01

    Chest radiographs and computed tomographic (CT) scans of the mediastinum were correlated with pathologic findings of the thymus following thymectomy in 57 patients with myasthenia gravis. Based on the patient's age and the overall morphology of the anterior mediastinum, CT scans were assigned one of four grades in an attempt to predict thymus pathologic findings. Using this grading, 14 of 16 cases of thymoma were suspected or definitely diagnosed. One of the two cases not diagnosed on CT was a microscopic tumor. There were no false-positive diagnoses in 11 cases graded as definitely thymoma. We conclude that thymoma can be sensitively diagnosed in patients older than 40 years of age. However, thymoma cannot be predicted with a high level of confidence in patients younger than 40 because of the difficulty in differentiating normal thymus or hyperplasia from thymoma. Recommendations for the use of CT in the preoperative evaluation of myasthenic patients are presented

  17. Neural Correlates of User-initiated Motor Success and Failure - A Brain-Computer Interface Perspective.

    Science.gov (United States)

    Yazmir, Boris; Reiner, Miriam

    2018-05-15

    Any motor action is, by nature, potentially accompanied by human errors. In order to facilitate development of error-tailored Brain-Computer Interface (BCI) correction systems, we focused on internal, human-initiated errors, and investigated EEG correlates of user outcome successes and errors during a continuous 3D virtual tennis game against a computer player. We used a multisensory, 3D, highly immersive environment. Missing and repelling the tennis ball were considered, as 'error' (miss) and 'success' (repel). Unlike most previous studies, where the environment "encouraged" the participant to perform a mistake, here errors happened naturally, resulting from motor-perceptual-cognitive processes of incorrect estimation of the ball kinematics, and can be regarded as user internal, self-initiated errors. Results show distinct and well-defined Event-Related Potentials (ERPs), embedded in the ongoing EEG, that differ across conditions by waveforms, scalp signal distribution maps, source estimation results (sLORETA) and time-frequency patterns, establishing a series of typical features that allow valid discrimination between user internal outcome success and error. The significant delay in latency between positive peaks of error- and success-related ERPs, suggests a cross-talk between top-down and bottom-up processing, represented by an outcome recognition process, in the context of the game world. Success-related ERPs had a central scalp distribution, while error-related ERPs were centro-parietal. The unique characteristics and sharp differences between EEG correlates of error/success provide the crucial components for an improved BCI system. The features of the EEG waveform can be used to detect user action outcome, to be fed into the BCI correction system. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  18. Electron correlation in molecules: concurrent computation Many-Body Perturbation Theory (ccMBPT) calculations using macrotasking on the NEC SX-3/44 computer

    International Nuclear Information System (INIS)

    Moncrieff, D.; Wilson, S.

    1992-06-01

    The ab initio determination of the electronic structure of molecules is a many-fermion problem involving the approximate description of the motion of the electrons in the field of fixed nuclei. It is an area of research which demands considerable computational resources but having enormous potential in fields as diverse as interstellar chemistry and drug design, catalysis and solid state chemistry, molecular biology and environmental chemistry. Electronic structure calculations almost invariably divide into two main stages: the approximate solution of an independent electron model, in which each electron moves in the average field created by the other electrons in the system, and then, the more computationally demanding determination of a series of corrections to this model, the electron correlation effects. The many-body perturbation theory expansion affords a systematic description of correlation effects, which leads directly to algorithms which are suitable for concurrent computation. We term this concurrent computation Many-Body Perturbation Theory (ccMBPT). The use of a dynamic load balancing technique on the NEC SX-3/44 computer in electron correlation calculations is investigated for the calculation of the most demanding energy component in the most accurate of contemporary ab initio studies. An application to the ground state of the nitrogen molecule is described. We also briefly discuss the extent to which the calculation of the dominant corrections to such studies can be rendered computationally tractable by exploiting both the vector processing and parallel processor capabilities of the NEC SX-3/44 computer. (author)

  19. WNoDeS, a tool for integrated Grid and Cloud access and computing farm virtualization

    International Nuclear Information System (INIS)

    Salomoni, Davide; Italiano, Alessandro; Ronchieri, Elisabetta

    2011-01-01

    INFN CNAF is the National Computing Center, located in Bologna, Italy, of the Italian National Institute for Nuclear Physics (INFN). INFN CNAF, also called the INFN Tier-1, provides computing and storage facilities to the International High-Energy Physics community and to several multi-disciplinary experiments. Currently, the INFN Tier-1 supports more than twenty different collaborations; in this context, optimization of the usage of computing resources is essential. This is one of the main drivers behind the development of a software called WNoDeS (Worker Nodes on Demand Service). WNoDeS, developed at INFN CNAF and deployed on the INFN Tier-1 production infrastructure, is a solution to virtualize computing resources and to make them available through local, Grid or Cloud interfaces. It is designed to be fully integrated with a Local Resource Management System; it is therefore inherently scalable and permits full integration with existing scheduling, policing, monitoring, accounting and security workflows. WNoDeS dynamically instantiates Virtual Machines (VMs) on-demand, i.e. only when the need arises; these VMs can be tailored and used for purposes like batch job execution, interactive analysis or service instantiation. WNoDeS supports interaction with user requests through traditional batch or Grid jobs and also via the Open Cloud Computing Interface standard, making it possible to allocate compute, storage and network resources on a pay-as-you-go basis. User authentication is supported via several authentication methods, while authorization policies are handled via gLite Argus. WNoDeS is an ambitious solution aimed at virtualizing cluster resources in medium or large scale computing centers, with up to several thousands of Virtual Machines up and running at any given time. In this paper, we describe the WNoDeS architecture.

  20. WNoDeS, a tool for integrated Grid and Cloud access and computing farm virtualization

    Science.gov (United States)

    Salomoni, Davide; Italiano, Alessandro; Ronchieri, Elisabetta

    2011-12-01

    INFN CNAF is the National Computing Center, located in Bologna, Italy, of the Italian National Institute for Nuclear Physics (INFN). INFN CNAF, also called the INFN Tier-1, provides computing and storage facilities to the International High-Energy Physics community and to several multi-disciplinary experiments. Currently, the INFN Tier-1 supports more than twenty different collaborations; in this context, optimization of the usage of computing resources is essential. This is one of the main drivers behind the development of a software called WNoDeS (Worker Nodes on Demand Service). WNoDeS, developed at INFN CNAF and deployed on the INFN Tier-1 production infrastructure, is a solution to virtualize computing resources and to make them available through local, Grid or Cloud interfaces. It is designed to be fully integrated with a Local Resource Management System; it is therefore inherently scalable and permits full integration with existing scheduling, policing, monitoring, accounting and security workflows. WNoDeS dynamically instantiates Virtual Machines (VMs) on-demand, i.e. only when the need arises; these VMs can be tailored and used for purposes like batch job execution, interactive analysis or service instantiation. WNoDeS supports interaction with user requests through traditional batch or Grid jobs and also via the Open Cloud Computing Interface standard, making it possible to allocate compute, storage and network resources on a pay-as-you-go basis. User authentication is supported via several authentication methods, while authorization policies are handled via gLite Argus. WNoDeS is an ambitious solution aimed at virtualizing cluster resources in medium or large scale computing centers, with up to several thousands of Virtual Machines up and running at any given time. In this paper, we descrive the WNoDeS architecture.

  1. Brain neuroimaging of domestic cats: correlation between computed tomography and cross-sectional anatomy

    International Nuclear Information System (INIS)

    Nepomuceno, A.C.; Zanatta, R.; Chung, D.G.; Costa, P.F.; Feliciano, M.A.R.; Avante, M.L.; Canola, J.C.; Lopes, L.S.

    2016-01-01

    Computed tomography of the brain is necessary as part of the diagnosis of lesions of the central nervous system. In this study we used six domestic cats, male or female, aged between one and five years, evaluated by Computed Tomography (CT) examination without clinical signs of central nervous system disorders. Two euthanized animals stating a condition unrelated to the nervous system were incorporated into this study. The proposal consisted in establishing detailed anatomical description of tomographic images of normal brain of cats, using as reference anatomical images of cross sections of the stained brain and cranial part, with thicknesses similar to the planes of the CT images. CT examinations were performed with and without intravenous iodinated contrast media for live animals. With one euthanized animal, the brain was removed and immediately preserved in 10% formalin for later achievement in cross-sectional thickness of approximately 4mm and staining technique of Barnard, and Robert Brown. The head of another animal was disarticulated in the Atlanto-occipital region and frozen at -20 deg C then sliced to a thickness of about 5mm. The description of visualized anatomical structures using tomography is useful as a guide and allows transcribing with relative accuracy the brain region affected by an injury, and thus correlating it with the clinical symptoms of the patient, providing additional information and consequent improvement to veterinarians during the course of surgical clinic in this species. (author)

  2. The neural correlates of problem states: testing FMRI predictions of a computational model of multitasking.

    Directory of Open Access Journals (Sweden)

    Jelmer P Borst

    Full Text Available BACKGROUND: It has been shown that people can only maintain one problem state, or intermediate mental representation, at a time. When more than one problem state is required, for example in multitasking, performance decreases considerably. This effect has been explained in terms of a problem state bottleneck. METHODOLOGY: In the current study we use the complimentary methodologies of computational cognitive modeling and neuroimaging to investigate the neural correlates of this problem state bottleneck. In particular, an existing computational cognitive model was used to generate a priori fMRI predictions for a multitasking experiment in which the problem state bottleneck plays a major role. Hemodynamic responses were predicted for five brain regions, corresponding to five cognitive resources in the model. Most importantly, we predicted the intraparietal sulcus to show a strong effect of the problem state manipulations. CONCLUSIONS: Some of the predictions were confirmed by a subsequent fMRI experiment, while others were not matched by the data. The experiment supported the hypothesis that the problem state bottleneck is a plausible cause of the interference in the experiment and that it could be located in the intraparietal sulcus.

  3. Brain neuroimaging of domestic cats: correlation between computed tomography and cross-sectional anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Nepomuceno, A.C. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Zanatta, R. [Universidade de Cuiaba, MT (Brazil); Chung, D.G.; Costa, P.F.; Feliciano, M.A.R.; Avante, M.L.; Canola, J.C., E-mail: marcusfeliciano@yahoo.com.br [Faculdade de Ciencias Agrarias e Veterinarias, Jaboticabal, SP (Brazil); Lopes, L.S. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil)

    2016-09-15

    Computed tomography of the brain is necessary as part of the diagnosis of lesions of the central nervous system. In this study we used six domestic cats, male or female, aged between one and five years, evaluated by Computed Tomography (CT) examination without clinical signs of central nervous system disorders. Two euthanized animals stating a condition unrelated to the nervous system were incorporated into this study. The proposal consisted in establishing detailed anatomical description of tomographic images of normal brain of cats, using as reference anatomical images of cross sections of the stained brain and cranial part, with thicknesses similar to the planes of the CT images. CT examinations were performed with and without intravenous iodinated contrast media for live animals. With one euthanized animal, the brain was removed and immediately preserved in 10% formalin for later achievement in cross-sectional thickness of approximately 4mm and staining technique of Barnard, and Robert Brown. The head of another animal was disarticulated in the Atlanto-occipital region and frozen at -20 deg C then sliced to a thickness of about 5mm. The description of visualized anatomical structures using tomography is useful as a guide and allows transcribing with relative accuracy the brain region affected by an injury, and thus correlating it with the clinical symptoms of the patient, providing additional information and consequent improvement to veterinarians during the course of surgical clinic in this species. (author)

  4. Computed tomography of delayed encephalopathy of acute carbon monoxide poisoning - correlation with clinical findings -

    International Nuclear Information System (INIS)

    Suh, Chang Hae; Chung, Sung Hoon; Choo, In Wook; Chang, Kee Hyun

    1986-01-01

    Cerebral computed tomography (CT) findings were described in twenty-six cases with the late sequelae of acute carbon monoxide poisoning and were computed with the neurological symptoms and signs. The CT findings include symmetrical periventricular white matter low density in five cases, globes pallidus low density in six cases, ventricular dilatation in seven cases, ventricular dilatation and sulci widening in three cases, and normal findings in ten cases. Only one case showed low densities in both periventricular white matter and globes pallidus. Late sequelae of the interval from of carbon monoxide poisoning were clinically categorized as cortical dysfunction, parkinsonian feature, and cerebella dysfunction. The severity of the clinical symptoms and signs of neurological sequelae is generally correlated with presence and multiplicity of abnormal brain CT findings. But of fourteen cases showing the parkinsonian feature, only five cases had low density of globes pallidus in brain CT. Another case showing small unilateral low density of globes pallidus had no parkinsonian feature but showed mild cortical dysfunction.

  5. Increasing Public Awareness of Direct-to-Consumer Genetic Tests: Health Care Access, Internet Use, and Population Density Correlates

    International Nuclear Information System (INIS)

    Rutten, L. J. F.; Gollust, S. E.; Naveed, S.; Moser, R. P.

    2012-01-01

    Uncertainty around the value of and appropriate regulatory models for direct-to-consumer (DTC) genetic testing underscores the importance of tracking public awareness of these services. We analyzed nationally representative, cross-sectional data from the Health Information National Trends Survey in 2008 (n=7, 674) and 2011 (n=3, 959) to assess population-level changes in awareness of DTC genetic testing in the U.S. and to explore socio demographic, health care, Internet use, and population density correlates. Overall, awareness increased significantly from 29% in 2008 to 37% in 2011. The observed increase in awareness from 2008 to 2011 remained significant (OR=1.39) even when adjusted for socio demographic variables, health care access, Internet use, and population density. Independent of survey year, the odds of awareness of DTC genetic tests were significantly higher for those aged 50-64 (OR=1.64), and 65-74 (O R=1.60); college graduates (OR=2.02 ); those with a regular source of health care (OR=1.27); those with a prior cancer diagnosis (OR=1.24); those who use the Internet (OR=1.27); and those living in urban areas ( OR=1.25). Surveillance of awareness-along with empirical data on use of and response to genetic risk information-can inform public health and policy efforts to maximize benefits and minimize risks of DTC genetic testing.

  6. Increasing Public Awareness of Direct-to-Consumer Genetic Tests: Health Care Access, Internet Use, and Population Density Correlates

    Directory of Open Access Journals (Sweden)

    Lila J. Finney Rutten

    2012-01-01

    Full Text Available Uncertainty around the value of and appropriate regulatory models for direct-to-consumer (DTC genetic testing underscores the importance of tracking public awareness of these services. We analyzed nationally representative, cross-sectional data from the Health Information National Trends Survey in 2008 (n=7,674 and 2011 (n=3,959 to assess population-level changes in awareness of DTC genetic testing in the U.S. and to explore sociodemographic, health care, Internet use, and population density correlates. Overall, awareness increased significantly from 29% in 2008 to 37% in 2011. The observed increase in awareness from 2008 to 2011 remained significant (OR=1.39 even when adjusted for sociodemographic variables, health care access, Internet use, and population density. Independent of survey year, the odds of awareness of DTC genetic tests were significantly higher for those aged 50–64 (OR=1.64, and 65–74 (OR=1.60; college graduates (OR=2.02; those with a regular source of health care (OR=1.27; those with a prior cancer diagnosis (OR=1.24; those who use the Internet (OR=1.27; and those living in urban areas (OR=1.25. Surveillance of awareness—along with empirical data on use of and response to genetic risk information—can inform public health and policy efforts to maximize benefits and minimize risks of DTC genetic testing.

  7. Increasing Public Awareness of Direct-to-Consumer Genetic Tests: Health Care Access, Internet Use, and Population Density Correlates.

    Science.gov (United States)

    Finney Rutten, Lila J; Gollust, Sarah E; Naveed, Sana; Moser, Richard P

    2012-01-01

    Uncertainty around the value of and appropriate regulatory models for direct-to-consumer (DTC) genetic testing underscores the importance of tracking public awareness of these services. We analyzed nationally representative, cross-sectional data from the Health Information National Trends Survey in 2008 (n = 7, 674) and 2011 (n = 3, 959) to assess population-level changes in awareness of DTC genetic testing in the U.S. and to explore sociodemographic, health care, Internet use, and population density correlates. Overall, awareness increased significantly from 29% in 2008 to 37% in 2011. The observed increase in awareness from 2008 to 2011 remained significant (OR = 1.39) even when adjusted for sociodemographic variables, health care access, Internet use, and population density. Independent of survey year, the odds of awareness of DTC genetic tests were significantly higher for those aged 50-64 (OR = 1.64), and 65-74 (OR = 1.60); college graduates (OR = 2.02); those with a regular source of health care (OR = 1.27); those with a prior cancer diagnosis (OR = 1.24); those who use the Internet (OR = 1.27); and those living in urban areas (OR = 1.25). Surveillance of awareness-along with empirical data on use of and response to genetic risk information-can inform public health and policy efforts to maximize benefits and minimize risks of DTC genetic testing.

  8. Hyperacute stroke patients and catheter thrombolysis therapy. Correlation between computed tomography perfusion maps and final infarction

    International Nuclear Information System (INIS)

    Naito, Yukari; Tanaka, Shigeko; Inoue, Yuichi; Ota, Shinsuke; Sakaki, Saburo; Kitagaki, Hajime

    2008-01-01

    We investigated the correlation between abnormal perfusion areas by computed tomography perfusion (CTP) study of hyperacute stroke patients and the final infarction areas after intraarterial catheter thrombolysis. CTP study using the box-modulation transfer function (box-MTF) method based on the deconvolution analysis method was performed in 22 hyperacute stroke patients. Ischemic lesions were immediately treated with catheter thrombolysis after CTP study. Among them, nine patients with middle cerebral artery (MCA) occlusion were investigated regarding correlations of the size of the prolonged mean transit time (MTT) area, the decreased cerebral blood volume (CBV) area, and the final infarction area. Using the box-MTF method, the prolonged MTT area was almost identical to the final infarction area in the case of catheter thrombolysis failure. The decreased CBV areas resulted in infarction or hemorrhage, irrespective of the outcome of recanalization after catheter thrombolysis. The prolonged MTT areas, detected by the box-MTF method of CTP in hyperacute stroke patients, included the area of true prolonged MTT and the tracer delay. The prolonged MTT area was almost identical to the final infarction area when recanalization failed. We believe that a tracer delay area also indicates infarction in cases of thrombolysis failure. (author)

  9. Correlation between presumed sinusitis-induced pain and paranasal sinus computed tomographic findings.

    Science.gov (United States)

    Mudgil, Shikha P; Wise, Scott W; Hopper, Kenneth D; Kasales, Claudia J; Mauger, David; Fornadley, John A

    2002-02-01

    The correlation between facial and/or head pain in patients clinically suspected of having sinusitis and actual localized findings on sinus computed tomographic (CT) imaging are poorly understood. To prospectively evaluate the relationship of paranasal sinus pain symptoms with CT imaging. Two hundred consecutive patients referred by otolaryngologists and internists for CT of the paranasal sinuses participated by completing a questionnaire immediately before undergoing CT. Three radiologists blinded to the patients' responses scored the degree of air/fluid level, mucosal thickening, bony reaction, and mucus retention cysts using a graded scale of severity (0 to 3 points). The osteomeatal complexes and nasolacrimal ducts were also evaluated for patency. Bivariate analysis was performed to evaluate the relationship between patients' localized symptoms and CT findings in the respective sinus. One hundred sixty-three patients (82%) reported having some form of facial pain or headache. The right temple/forehead was the most frequently reported region of maximal pain. On CT imaging the maxillary sinus was the most frequently involved sinus. Bivariate analysis failed to show any relationship between patient symptoms and findings on CT. Patients with a normal CT reported a mean 5.88 sites of facial or head pain versus 5.45 sites for patients with an abnormal CT. Patient-based responses of sinonasal pain symptoms fail to correlate with findings in the respective sinuses. CT should therefore be reserved for delineating the anatomy and degree of sinus disease before surgical intervention.

  10. Time-Shift Correlation Algorithm for P300 Event Related Potential Brain-Computer Interface Implementation

    Directory of Open Access Journals (Sweden)

    Ju-Chi Liu

    2016-01-01

    Full Text Available A high efficient time-shift correlation algorithm was proposed to deal with the peak time uncertainty of P300 evoked potential for a P300-based brain-computer interface (BCI. The time-shift correlation series data were collected as the input nodes of an artificial neural network (ANN, and the classification of four LED visual stimuli was selected as the output node. Two operating modes, including fast-recognition mode (FM and accuracy-recognition mode (AM, were realized. The proposed BCI system was implemented on an embedded system for commanding an adult-size humanoid robot to evaluate the performance from investigating the ground truth trajectories of the humanoid robot. When the humanoid robot walked in a spacious area, the FM was used to control the robot with a higher information transfer rate (ITR. When the robot walked in a crowded area, the AM was used for high accuracy of recognition to reduce the risk of collision. The experimental results showed that, in 100 trials, the accuracy rate of FM was 87.8% and the average ITR was 52.73 bits/min. In addition, the accuracy rate was improved to 92% for the AM, and the average ITR decreased to 31.27 bits/min. due to strict recognition constraints.

  11. Pulmonary mucormycosis. Serial morphologic changes on computed tomography correlate with clinical and pathologic findings

    International Nuclear Information System (INIS)

    Nam, Bo Da; Kim, Tae Jung; Lee, Kyung Soo; Kim, Tae Sung; Chung, Myung Jin; Han, Joungho

    2018-01-01

    To evaluate serial computed tomography (CT) findings of pulmonary mucormycosis correlated with peripheral blood absolute neutrophil count (ANC). Between February 1997 and June 2016, 20 immunocompromised patients (10 males, 10 females; mean age, 48.9 years) were histopathologically diagnosed as pulmonary mucormycosis. On initial (n=20) and follow-up (n=15) CT scans, the patterns of lung abnormalities and their changing features on follow-up scans were evaluated, and the pattern changes were correlated with ANC changes. All patients were immunocompromised. On initial CT scans, nodule (≤3cm)/mass (>3cm) or consolidation with surrounding ground-glass opacity halo (18/20, 90%) was the most common pattern. On follow-up CT, morphologic changes (13/15, 87%) could be seen and they included reversed halo (RH) sign, central necrosis, and air-crescent sign. Although all cases did not demonstrate the regular morphologic changes at the same timeline, various combinations of pattern change could be seen in all patients. Sequential morphologic changes were related with recovering of ANC in 13 of 15 patients. Pulmonary mucormycosis most frequently presents as consolidation or nodule/mass with halo sign at CT. Morphologic changes into RH sign, central necrotic cavity or air-crescent sign occur with treatment and recovery of ANC. (orig.)

  12. Time-Shift Correlation Algorithm for P300 Event Related Potential Brain-Computer Interface Implementation.

    Science.gov (United States)

    Liu, Ju-Chi; Chou, Hung-Chyun; Chen, Chien-Hsiu; Lin, Yi-Tseng; Kuo, Chung-Hsien

    2016-01-01

    A high efficient time-shift correlation algorithm was proposed to deal with the peak time uncertainty of P300 evoked potential for a P300-based brain-computer interface (BCI). The time-shift correlation series data were collected as the input nodes of an artificial neural network (ANN), and the classification of four LED visual stimuli was selected as the output node. Two operating modes, including fast-recognition mode (FM) and accuracy-recognition mode (AM), were realized. The proposed BCI system was implemented on an embedded system for commanding an adult-size humanoid robot to evaluate the performance from investigating the ground truth trajectories of the humanoid robot. When the humanoid robot walked in a spacious area, the FM was used to control the robot with a higher information transfer rate (ITR). When the robot walked in a crowded area, the AM was used for high accuracy of recognition to reduce the risk of collision. The experimental results showed that, in 100 trials, the accuracy rate of FM was 87.8% and the average ITR was 52.73 bits/min. In addition, the accuracy rate was improved to 92% for the AM, and the average ITR decreased to 31.27 bits/min. due to strict recognition constraints.

  13. Correlation of radiation dose and heart rate in dual-source computed tomography coronary angiography.

    Science.gov (United States)

    Laspas, Fotios; Tsantioti, Dimitra; Roussakis, Arkadios; Kritikos, Nikolaos; Efthimiadou, Roxani; Kehagias, Dimitrios; Andreou, John

    2011-04-01

    Computed tomography coronary angiography (CTCA) has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but the relatively high radiation dose remains a major concern. To evaluate the relationship between radiation exposure and heart rate (HR), in dual-source CTCA. Data from 218 CTCA examinations, performed with a dual-source 64-slices scanner, were statistically evaluated. Effective radiation dose, expressed in mSv, was calculated as the product of the dose-length product (DLP) times a conversion coefficient for the chest (mSv = DLPx0.017). Heart rate range and mean heart rate, expressed in beats per minute (bpm) of each individual during CTCA, were also provided by the system. Statistical analysis of effective dose and heart rate data was performed by using Pearson correlation coefficient and two-sample t-test. Mean HR and effective dose were found to have a borderline positive relationship. Individuals with a mean HR >65 bpm observed to receive a statistically significant higher effective dose as compared to those with a mean HR ≤65 bpm. Moreover, a strong correlation between effective dose and variability of HR of more than 20 bpm was observed. Dual-source CT scanners are considered to have the capability to provide diagnostic examinations even with high HR and arrhythmias. However, it is desirable to keep the mean heart rate below 65 bpm and heart rate fluctuation less than 20 bpm in order to reduce the radiation exposure.

  14. Pulmonary mucormycosis. Serial morphologic changes on computed tomography correlate with clinical and pathologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Bo Da; Kim, Tae Jung; Lee, Kyung Soo; Kim, Tae Sung; Chung, Myung Jin [Samsung Medical Centre, Sungkyunkwan University School of Medicine, Department of Radiology and Centre for Imaging Science, Seoul (Korea, Republic of); Han, Joungho [Samsung Medical Centre, Sungkyunkwan University School of Medicine, Department of Pathology, Seoul (Korea, Republic of)

    2018-02-15

    To evaluate serial computed tomography (CT) findings of pulmonary mucormycosis correlated with peripheral blood absolute neutrophil count (ANC). Between February 1997 and June 2016, 20 immunocompromised patients (10 males, 10 females; mean age, 48.9 years) were histopathologically diagnosed as pulmonary mucormycosis. On initial (n=20) and follow-up (n=15) CT scans, the patterns of lung abnormalities and their changing features on follow-up scans were evaluated, and the pattern changes were correlated with ANC changes. All patients were immunocompromised. On initial CT scans, nodule (≤3cm)/mass (>3cm) or consolidation with surrounding ground-glass opacity halo (18/20, 90%) was the most common pattern. On follow-up CT, morphologic changes (13/15, 87%) could be seen and they included reversed halo (RH) sign, central necrosis, and air-crescent sign. Although all cases did not demonstrate the regular morphologic changes at the same timeline, various combinations of pattern change could be seen in all patients. Sequential morphologic changes were related with recovering of ANC in 13 of 15 patients. Pulmonary mucormycosis most frequently presents as consolidation or nodule/mass with halo sign at CT. Morphologic changes into RH sign, central necrotic cavity or air-crescent sign occur with treatment and recovery of ANC. (orig.)

  15. Assessing motor imagery in brain-computer interface training: Psychological and neurophysiological correlates.

    Science.gov (United States)

    Vasilyev, Anatoly; Liburkina, Sofya; Yakovlev, Lev; Perepelkina, Olga; Kaplan, Alexander

    2017-03-01

    Motor imagery (MI) is considered to be a promising cognitive tool for improving motor skills as well as for rehabilitation therapy of movement disorders. It is believed that MI training efficiency could be improved by using the brain-computer interface (BCI) technology providing real-time feedback on person's mental attempts. While BCI is indeed a convenient and motivating tool for practicing MI, it is not clear whether it could be used for predicting or measuring potential positive impact of the training. In this study, we are trying to establish whether the proficiency in BCI control is associated with any of the neurophysiological or psychological correlates of motor imagery, as well as to determine possible interrelations among them. For that purpose, we studied motor imagery in a group of 19 healthy BCI-trained volunteers and performed a correlation analysis across various quantitative assessment metrics. We examined subjects' sensorimotor event-related EEG events, corticospinal excitability changes estimated with single-pulse transcranial magnetic stimulation (TMS), BCI accuracy and self-assessment reports obtained with specially designed questionnaires and interview routine. Our results showed, expectedly, that BCI performance is dependent on the subject's capability to suppress EEG sensorimotor rhythms, which in turn is correlated with the idle state amplitude of those oscillations. Neither BCI accuracy nor the EEG features associated with MI were found to correlate with the level of corticospinal excitability increase during motor imagery, and with assessed imagery vividness. Finally, a significant correlation was found between the level of corticospinal excitability increase and kinesthetic vividness of imagery (KVIQ-20 questionnaire). Our results suggest that two distinct neurophysiological mechanisms might mediate possible effects of motor imagery: the non-specific cortical sensorimotor disinhibition and the focal corticospinal excitability increase

  16. Correlation of chest computed tomography findings with dyspnea and lung functions in post-tubercular sequelae

    Directory of Open Access Journals (Sweden)

    Ananya Panda

    2016-01-01

    Full Text Available Aims: To study the correlation between dyspnea, radiological findings, and pulmonary function tests (PFTs in patients with sequelae of pulmonary tuberculosis (TB. Materials and Methods: Clinical history, chest computed tomography (CT, and PFT of patients with post-TB sequelae were recorded. Dyspnea was graded according to the Modified Medical Research Council (mMRC scale. CT scans were analyzed for fibrosis, cavitation, bronchiectasis, consolidation, nodules, and aspergilloma. Semi-quantitative analysis was done for these abnormalities. Scores were added to obtain a total morphological score (TMS. The lungs were also divided into three zones and scores added to obtain the total lung score (TLS. Spirometry was done for forced vital capacity (FVC, forced expiratory volume in 1 s (FEV1, and FEV1/FVC. Results: Dyspnea was present in 58/101 patients. A total of 22/58 patients had mMRC Grade 1, and 17/58 patients had Grades 2 and 3 dyspnea each. There was a significant difference in median fibrosis, bronchiectasis, nodules (P < 0.01 scores, TMS, and TLS (P < 0.0001 between dyspnea and nondyspnea groups. Significant correlations were obtained between grades of dyspnea and fibrosis (r = 0.34, P = 0.006, bronchiectasis (r = 0.35, P = 0.004, nodule (r = 0.24, P = 0.016 scores, TMS (r = 0.398, P = 0.000, and TLS (r = 0.35, P = 0.0003. PFTs were impaired in 78/101 (77.2% patients. Restrictive defect was most common in 39.6% followed by mixed in 34.7%. There was a negative but statistically insignificant trend between PFT and fibrosis, bronchiectasis, nodule scores, TMS, and TLS. However, there were significant differences in median fibrosis, cavitation, and bronchiectasis scores in patients with normal, mild to moderate, and severe respiratory defects. No difference was seen in TMS and TLS according to the severity of the respiratory defect. Conclusion: Both fibrosis and bronchiectasis correlated with dyspnea and with PFT. However, this correlation was not

  17. A Web-based computer system supporting information access, exchange and management during building processes

    DEFF Research Database (Denmark)

    Sørensen, Lars Schiøtt

    1998-01-01

    During the last two decades, a number of research efforts have been made in the field of computing systmes related to the building construction industry. Most of the projects have focused on a part of the entire design process and have typically been limited to a specific domain. This paper prese...... presents a newly developed computer system based on the World Wide Web on the Internet. The focus is on the simplicity of the systems structure and on an intuitive and user friendly interface...

  18. Using Palm Technology in Participatory Simulations of Complex Systems: A New Take on Ubiquitous and Accessible Mobile Computing

    Science.gov (United States)

    Klopfer, Eric; Yoon, Susan; Perry, Judy

    2005-09-01

    This paper reports on teachers' perceptions of the educational affordances of a handheld application called Participatory Simulations. It presents evidence from five cases representing each of the populations who work with these computational tools. Evidence across multiple data sources yield similar results to previous research evaluations of handheld activities with respect to enhancing motivation, engagement and self-directed learning. Three additional themes are discussed that provide insight into understanding curricular applicability of Participatory Simulations that suggest a new take on ubiquitous and accessible mobile computing. These themes generally point to the multiple layers of social and cognitive flexibility intrinsic to their design: ease of adaptation to subject-matter content knowledge and curricular integration; facility in attending to teacher-individualized goals; and encouraging the adoption of learner-centered strategies.

  19. An energy efficient and high speed architecture for convolution computing based on binary resistive random access memory

    Science.gov (United States)

    Liu, Chen; Han, Runze; Zhou, Zheng; Huang, Peng; Liu, Lifeng; Liu, Xiaoyan; Kang, Jinfeng

    2018-04-01

    In this work we present a novel convolution computing architecture based on metal oxide resistive random access memory (RRAM) to process the image data stored in the RRAM arrays. The proposed image storage architecture shows performances of better speed-device consumption efficiency compared with the previous kernel storage architecture. Further we improve the architecture for a high accuracy and low power computing by utilizing the binary storage and the series resistor. For a 28 × 28 image and 10 kernels with a size of 3 × 3, compared with the previous kernel storage approach, the newly proposed architecture shows excellent performances including: 1) almost 100% accuracy within 20% LRS variation and 90% HRS variation; 2) more than 67 times speed boost; 3) 71.4% energy saving.

  20. Towards an anonymous access control and accountability scheme for cloud computing

    DEFF Research Database (Denmark)

    Jensen, Meiko; Schäge, Sven; Schwenk, Jörg

    2010-01-01

    An important aspect of trust in cloud computing consists in preventing the cloud provider from misusing the user's data. In this work-in-progress paper, we propose the approach of data anonymization to solve this problem. As this directly leads to problems of cloud usage accounting, we also propose...

  1. Understanding and Improving Blind Students' Access to Visual Information in Computer Science Education

    Science.gov (United States)

    Baker, Catherine M.

    2017-01-01

    Teaching people with disabilities tech skills empowers them to create solutions to problems they encounter and prepares them for careers. However, computer science is typically taught in a highly visual manner which can present barriers for people who are blind. The goal of this dissertation is to understand and decrease those barriers. The first…

  2. The ENSDF radioactivity data base for IBM-PC and computer network access

    International Nuclear Information System (INIS)

    Ekstroem, P.; Spanier, L.

    1989-08-01

    A database for about 15000 gamma rays from 2777 radioactive nuclides derived from the international Evaluated Nuclear Structure Data File (ENSDF) is described together with supporting computer codes. The database is available on a PC diskette, costfree, from the IAEA Nuclear Data Section. (author)

  3. Development traumatic brain injury computer user interface for disaster area in Indonesia supported by emergency broadband access network.

    Science.gov (United States)

    Sutiono, Agung Budi; Suwa, Hirohiko; Ohta, Toshizumi; Arifin, Muh Zafrullah; Kitamura, Yohei; Yoshida, Kazunari; Merdika, Daduk; Qiantori, Andri; Iskandar

    2012-12-01

    Disasters bring consequences of negative impacts on the environment and human life. One of the common cause of critical condition is traumatic brain injury (TBI), namely, epidural (EDH) and subdural hematoma (SDH), due to downfall hard things during earthquake. We proposed and analyzed the user response, namely neurosurgeon, general doctor/surgeon and nurse when they interacted with TBI computer interface. The communication systems was supported by TBI web based applications using emergency broadband access network with tethered balloon and simulated in the field trial to evaluate the coverage area. The interface consisted of demography data and multi tabs for anamnesis, treatment, follow up and teleconference interfaces. The interface allows neurosurgeon, surgeon/general doctors and nurses to entry the EDH and SDH patient's data during referring them on the emergency simulation and evaluated based on time needs and their understanding. The average time needed was obtained after simulated by Lenovo T500 notebook using mouse; 8-10 min for neurosurgeons, 12-15 min for surgeons/general doctors and 15-19 min for nurses. By using Think Pad X201 Tablet, the time needed for entry data was 5-7 min for neurosurgeon, 7-10 min for surgeons/general doctors and 12-16 min for nurses. We observed that the time difference was depending on the computer type and user literacy qualification as well as their understanding on traumatic brain injury, particularly for the nurses. In conclusion, there are five data classification for simply TBI GUI, namely, 1) demography, 2) specific anamnesis for EDH and SDH, 3) treatment action and medicine of TBI, 4) follow up data display and 5) teleneurosurgery for streaming video consultation. The type of computer, particularly tablet PC was more convenient and faster for entry data, compare to that computer mouse touched pad. Emergency broadband access network using tethered balloon is possible to be employed to cover the communications systems in

  4. Improving Inpatient Surveys: Web-Based Computer Adaptive Testing Accessed via Mobile Phone QR Codes.

    Science.gov (United States)

    Chien, Tsair-Wei; Lin, Weir-Sen

    2016-03-02

    The National Health Service (NHS) 70-item inpatient questionnaire surveys inpatients on their perceptions of their hospitalization experience. However, it imposes more burden on the patient than other similar surveys. The literature shows that computerized adaptive testing (CAT) based on item response theory can help shorten the item length of a questionnaire without compromising its precision. Our aim was to investigate whether CAT can be (1) efficient with item reduction and (2) used with quick response (QR) codes scanned by mobile phones. After downloading the 2008 inpatient survey data from the Picker Institute Europe website and analyzing the difficulties of this 70-item questionnaire, we used an author-made Excel program using the Rasch partial credit model to simulate 1000 patients' true scores followed by a standard normal distribution. The CAT was compared to two other scenarios of answering all items (AAI) and the randomized selection method (RSM), as we investigated item length (efficiency) and measurement accuracy. The author-made Web-based CAT program for gathering patient feedback was effectively accessed from mobile phones by scanning the QR code. We found that the CAT can be more efficient for patients answering questions (ie, fewer items to respond to) than either AAI or RSM without compromising its measurement accuracy. A Web-based CAT inpatient survey accessed by scanning a QR code on a mobile phone was viable for gathering inpatient satisfaction responses. With advances in technology, patients can now be offered alternatives for providing feedback about hospitalization satisfaction. This Web-based CAT is a possible option in health care settings for reducing the number of survey items, as well as offering an innovative QR code access.

  5. Big Data solutions on a small scale: Evaluating accessible high-performance computing for social research

    Directory of Open Access Journals (Sweden)

    Dhiraj Murthy

    2014-11-01

    Full Text Available Though full of promise, Big Data research success is often contingent on access to the newest, most advanced, and often expensive hardware systems and the expertise needed to build and implement such systems. As a result, the accessibility of the growing number of Big Data-capable technology solutions has often been the preserve of business analytics. Pay as you store/process services like Amazon Web Services have opened up possibilities for smaller scale Big Data projects. There is high demand for this type of research in the digital humanities and digital sociology, for example. However, scholars are increasingly finding themselves at a disadvantage as available data sets of interest continue to grow in size and complexity. Without a large amount of funding or the ability to form interdisciplinary partnerships, only a select few find themselves in the position to successfully engage Big Data. This article identifies several notable and popular Big Data technologies typically implemented using large and extremely powerful cloud-based systems and investigates the feasibility and utility of development of Big Data analytics systems implemented using low-cost commodity hardware in basic and easily maintainable configurations for use within academic social research. Through our investigation and experimental case study (in the growing field of social Twitter analytics, we found that not only are solutions like Cloudera’s Hadoop feasible, but that they can also enable robust, deep, and fruitful research outcomes in a variety of use-case scenarios across the disciplines.

  6. Photon echo quantum random access memory integration in a quantum computer

    International Nuclear Information System (INIS)

    Moiseev, Sergey A; Andrianov, Sergey N

    2012-01-01

    We have analysed an efficient integration of multi-qubit echo quantum memory (QM) into the quantum computer scheme based on squids, quantum dots or atomic resonant ensembles in a quantum electrodynamics cavity. Here, one atomic ensemble with controllable inhomogeneous broadening is used for the QM node and other nodes characterized by the homogeneously broadened resonant line are used for processing. We have found the optimal conditions for the efficient integration of the multi-qubit QM modified for the analysed scheme, and we have determined the self-temporal modes providing a perfect reversible transfer of the photon qubits between the QM node and arbitrary processing nodes. The obtained results open the way for realization of a full-scale solid state quantum computing based on the efficient multi-qubit QM. (paper)

  7. How computers can help us in creating an intuitive access to relativity

    Energy Technology Data Exchange (ETDEWEB)

    Ruder, Hanns; Nollert, Hans-Peter [Theoretical Astrophysics, University of Tuebingen, Auf der Morgenstelle 10, 72076 Tuebingen (Germany); Weiskopf, Daniel; Mueller, Thomas [VISUS (Visualization Research Center), Universitaet Stuttgart, Nobelstr. 15, 70569 Stuttgart (Germany)], E-mail: nollert@tat.physik.uni-tuebingen.de

    2008-12-15

    Computers have added many new possibilities to the tool box used for visualizing science in general and relativity in particular. We present some new results from our own work: (2+1) dimensional Minkowski diagrams showing two spatial dimensions, extended wormhole visualization, and the illustration of accretion discs by using the approximation via a rigidly rotating disc of dust. We also discuss some related examples from our earlier work, such as interactive and immersive visualization, or the visualization of the warp drive metric.

  8. How computers can help us in creating an intuitive access to relativity

    International Nuclear Information System (INIS)

    Ruder, Hanns; Nollert, Hans-Peter; Weiskopf, Daniel; Mueller, Thomas

    2008-01-01

    Computers have added many new possibilities to the tool box used for visualizing science in general and relativity in particular. We present some new results from our own work: (2+1) dimensional Minkowski diagrams showing two spatial dimensions, extended wormhole visualization, and the illustration of accretion discs by using the approximation via a rigidly rotating disc of dust. We also discuss some related examples from our earlier work, such as interactive and immersive visualization, or the visualization of the warp drive metric.

  9. COMPUTING

    CERN Multimedia

    I. Fisk

    2013-01-01

    Computing activity had ramped down after the completion of the reprocessing of the 2012 data and parked data, but is increasing with new simulation samples for analysis and upgrade studies. Much of the Computing effort is currently involved in activities to improve the computing system in preparation for 2015. Operations Office Since the beginning of 2013, the Computing Operations team successfully re-processed the 2012 data in record time, not only by using opportunistic resources like the San Diego Supercomputer Center which was accessible, to re-process the primary datasets HTMHT and MultiJet in Run2012D much earlier than planned. The Heavy-Ion data-taking period was successfully concluded in February collecting almost 500 T. Figure 3: Number of events per month (data) In LS1, our emphasis is to increase efficiency and flexibility of the infrastructure and operation. Computing Operations is working on separating disk and tape at the Tier-1 sites and the full implementation of the xrootd federation ...

  10. COPD phenotypes on computed tomography and its correlation with selected lung function variables in severe patients

    Directory of Open Access Journals (Sweden)

    da Silva SMD

    2016-03-01

    Full Text Available Silvia Maria Doria da Silva, Ilma Aparecida Paschoal, Eduardo Mello De Capitani, Marcos Mello Moreira, Luciana Campanatti Palhares, Mônica Corso PereiraPneumology Service, Department of Internal Medicine, School of Medical Sciences, State University of Campinas (UNICAMP, Campinas, São Paulo, BrazilBackground: Computed tomography (CT phenotypic characterization helps in understanding the clinical diversity of chronic obstructive pulmonary disease (COPD patients, but its clinical relevance and its relationship with functional features are not clarified. Volumetric capnography (VC uses the principle of gas washout and analyzes the pattern of CO2 elimination as a function of expired volume. The main variables analyzed were end-tidal concentration of carbon dioxide (ETCO2, Slope of phase 2 (Slp2, and Slope of phase 3 (Slp3 of capnogram, the curve which represents the total amount of CO2 eliminated by the lungs during each breath.Objective: To investigate, in a group of patients with severe COPD, if the phenotypic analysis by CT could identify different subsets of patients, and if there was an association of CT findings and functional variables.Subjects and methods: Sixty-five patients with COPD Gold III–IV were admitted for clinical evaluation, high-resolution CT, and functional evaluation (spirometry, 6-minute walk test [6MWT], and VC. The presence and profusion of tomography findings were evaluated, and later, the patients were identified as having emphysema (EMP or airway disease (AWD phenotype. EMP and AWD groups were compared; tomography findings scores were evaluated versus spirometric, 6MWT, and VC variables.Results: Bronchiectasis was found in 33.8% and peribronchial thickening in 69.2% of the 65 patients. Structural findings of airways had no significant correlation with spirometric variables. Air trapping and EMP were strongly correlated with VC variables, but in opposite directions. There was some overlap between the EMP and AWD

  11. Early Lung Adenocarcinoma in Mice: Micro-Computed Tomography Manifestations and Correlation with Pathology

    Directory of Open Access Journals (Sweden)

    Lin Deng

    2017-06-01

    Full Text Available Lung cancer is the most common fatal malignancy for both men and women and adenocarcinoma is the most common histologic type. Early diagnosis of lung cancer can significantly improve the survival rate of patients. This study aimed to investigate the micro-computed tomography (micro-CT manifestations of early lung adenocarcinoma (LAC in mice and to provide a new perspective for early clinical diagnosis. Early LAC models in 10 mice were established by subcutaneously injecting 1-methyl-3-nitro-1-nitrosoguanidine (MNNG solution. Micro-CT scan and multiple planar reconstruction (MPR were used for mouse lungs. Micro-CT features of early LAC, especially the relationships between tumor and bronchus, were analyzed and correlated with pathology. Micro-CT findings of early LAC were divided into three types: non-solid (n = 8, 6%, partly solid (n = 85, 64% and totally solid (n = 39, 30%. Tumor-bronchus relationships, which could be observed in 110 of 132(83% LAC, were classified into four patterns: type I (n = 16, 15%, bronchus was truncated at the margin of the tumor; type II (n = 33, 30%, bronchus penetrated into the tumor with tapered narrowing and interruption; type III (n = 38, 35%, bronchus penetrated into the tumor with a patent and intact lumen; type IV (n = 99, 90%, bronchus ran at the border of the tumor with an intact or compressed lumen. Micro-CT manifestations of early LAC correlated well with pathological findings. Micro-CT can clearly demonstrate the features of mouse early LAC and bronchus-tumor relationships, and can also provide a new tool and perspective for the study of early LAC.

  12. Hepatic contrast medium enhancement at computed tomography and its correlation with various body size measures

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Anders; Nouhad, Jallo; Cederlund, Kerstin; Aspelin, Peter; Torkel, Brismar B., E-mail: anders.svensson@karolinska.se [Dept. of Clinical Science, Intervention and Technology at Karolinska Inst., Div. of Medical Imaging and Technology, Stockholm (Sweden); (Dept. of Radiology, Karolinska Univ. Hospital, Huddinge, Stockholm (Sweden)); Nyman, Ulf (Dept. of Diagnostic Radiology, Lasarettet Trelleborg, Univ. of Lund, Trelleborg (Sweden)); Bjoerk, Jonas (Competence Centre for Clinical Research, Skaane Univ. Hospital, Lund (Sweden)

    2012-07-15

    Background. When the same dose of iodine is given to all patients when performing abdominal computed tomography (CT) there may be a wide inter-individual variation in contrast medium (CM) enhancement of the liver. Purpose. To evaluate if any of the measures body height (BH), body mass index (BMI), lean body mass (LBM), ideal body weight (IBW), and body surface area (BSA) correlated better than body weight (BW) with hepatic enhancement, and to compare the enhancement when using iodixanol and iomeprol. Material and Methods. One hundred patients referred for standard three-phase CT examination of abdomen were enrolled. Body weight and height were measured at the time of the CT examination. Forty grams of iodine (iodixanol 320 mg I/mL or iomeprol 400 mg I/mL) was injected at a rate of 1.6 g-I/s, followed by a 50 mL saline flush. The late arterial phase was determined by using a semi-automatic smart prep technique with a scan delay of 20 s. The hepatic parenchymal phase started automatically 25 s after the late arterial phase. CM concentration was estimated by placement of regions of interest in aorta (native and late arterial phase) and in liver (native and parenchymal phase). Results. BW (r -0.51 and -0.64), LBM (r = -0.54 and -0.59), and BSA (r -0.54 and -0.65) showed the best correlation coefficients with aortic and hepatic parenchymal enhancement, respectively, without any significant differences between the measures. Comparing iodixanol and iomeprol there was no significant difference in aortic enhancement. The liver enhancement was significantly higher (P < 0.05) using iodixanol than iomeprol. Conclusion. To achieve a consistent hepatic enhancement, CM dose may simply be adjusted to body weight instead of using more complicated calculated parameters based on both weight and height.

  13. Correlation of abdominopelvic computed tomography with clinical manifestations in methamphetamine body stuffers.

    Science.gov (United States)

    Bahrami-Motlagh, Hooman; Hassanian-Moghaddam, Hossein; Zamini, Hedieh; Zamani, Nasim; Gachkar, Latif

    2018-02-01

    Little is known about methamphetamine body stuffers and correlation of clinical manifestations with imaging studies. Current study was done to determine abdominopelvic computed tomography findings and clinical manifestations in methamphetamine body stuffers. In an IRB-approved routine data base study, demographic characteristics, clinical findings, and CT results of 70 methamphetamine body stuffers were retrieved. According to the clinical manifestations, the patients were categorized into either benign- or severe-outcome group. Also, they were determined to have positive or negative CT results. In the group with positive results, number and place of the baggies were determined, as well. Results of the CT were compared between the two groups. Almost 43% of the patients had positive abdominopelvic CT results. Mean density of the packs was 176.2 ± 152.7 Hounsfield unit. Based on the clinical grounds, 57% of the patients were in the benign- and 33% were in the severe-outcome group. In the benign group, 45% of the patients had positive CTs while in the severe-risk group, this was 40% (p > 0.05). Except variables defined as severe outcome (seizure, intubation, creatinine level, aspartate aminotransferase level, creatine phosphokinase and troponin level), agitation, on-arrival pulse rate, lactate dehydrogenase, bicarbonate, base excess, loss of consciousness and hospitalization period were correlating factors. But in regression analysis, we could not find a significant variable that prognosticate severe outcome. It seems that there is no relationship between the CT findings and clinical manifestations of the methamphetamine body stuffers. Severe outcomes may be observed even in the face of negative CTs.

  14. Computed Tomography Appearance of Early Radiation Injury to the Lung: Correlation With Clinical and Dosimetric Factors

    International Nuclear Information System (INIS)

    Jenkins, Peter; Welsh, Anne

    2011-01-01

    Purpose: To systematically assess the spectrum of radiologic changes in the lung after radiation therapy for non-small-cell lung cancer. Methods and Materials: We reviewed the cases of 146 patients treated with radical radiotherapy at our institution. All patients had computed tomography (CT) scans performed 3 months after completion of therapy. Radiographic appearances were categorized using a standard grading system. The association of these abnormalities with pretreatment factors and clinical radiation pneumonitis (RP) was investigated. Results: New intrapulmonary abnormalities were seen in 92 patients (63%). These were ground-glass opacity in 16 (11%), patchy consolidation in 19 (13%), and diffuse consolidation in 57 (39%). Twenty-five patients (17%) developed clinical symptoms of RP. Although 80% of the patients with RP had areas of consolidation seen on the posttreatment CT scan, the majority (74%) of patients with such radiographic changes were asymptomatic. For patients with lung infiltrates, the minimum isodose encompassing the volume of radiologic abnormality was usually ≥27 Gy. Traditional dose-volume metrics, pulmonary function tests, and the coadministration of angiotensin converting enzyme inhibitors (ACE-I) were all strongly correlated with the presence of radiologic injury on univariate analysis (p ≤ 0.002). There was also an inverse correlation between prior smoking history and CT scan changes (p = 0.02). On multivariate analysis, dosimetric parameters and the use of ACE-I retained significance (p = 0.005). Conclusions: Our findings suggest that there is substantial interindividual variation in lung radiosensitivity. ACE-I prevented the radiologic changes seen after high-dose radiation therapy, and their role as radioprotectants warrants further investigation.

  15. Correlation of radiation dose and heart rate in dual-source computed tomography coronary angiography

    International Nuclear Information System (INIS)

    Laspas, Fotios; Roussakis, Arkadios; Kritikos, Nikolaos; Efthimiadou, Roxani; Kehagias, Dimitrios; Andreou, John; Tsantioti, Dimitra

    2011-01-01

    Background: Computed tomography coronary angiography (CTCA) has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but the relatively high radiation dose remains a major concern. Purpose: To evaluate the relationship between radiation exposure and heart rate (HR), in dual-source CTCA. Material and Methods: Data from 218 CTCA examinations, performed with a dual-source 64-slices scanner, were statistically evaluated. Effective radiation dose, expressed in mSv, was calculated as the product of the dose-length product (DLP) times a conversion coefficient for the chest (mSv = DLPx0.017). Heart rate range and mean heart rate, expressed in beats per minute (bpm) of each individual during CTCA, were also provided by the system. Statistical analysis of effective dose and heart rate data was performed by using Pearson correlation coefficient and two-sample t-test. Results: Mean HR and effective dose were found to have a borderline positive relationship. Individuals with a mean HR >65 bpm observed to receive a statistically significant higher effective dose as compared to those with a mean HR =65 bpm. Moreover, a strong correlation between effective dose and variability of HR of more than 20 bpm was observed. Conclusion: Dual-source CT scanners are considered to have the capability to provide diagnostic examinations even with high HR and arrhythmias. However, it is desirable to keep the mean heart rate below 65 bpm and heart rate fluctuation less than 20 bpm in order to reduce the radiation exposure

  16. Optical interconnection network for parallel access to multi-rank memory in future computing systems.

    Science.gov (United States)

    Wang, Kang; Gu, Huaxi; Yang, Yintang; Wang, Kun

    2015-08-10

    With the number of cores increasing, there is an emerging need for a high-bandwidth low-latency interconnection network, serving core-to-memory communication. In this paper, aiming at the goal of simultaneous access to multi-rank memory, we propose an optical interconnection network for core-to-memory communication. In the proposed network, the wavelength usage is delicately arranged so that cores can communicate with different ranks at the same time and broadcast for flow control can be achieved. A distributed memory controller architecture that works in a pipeline mode is also designed for efficient optical communication and transaction address processes. The scaling method and wavelength assignment for the proposed network are investigated. Compared with traditional electronic bus-based core-to-memory communication, the simulation results based on the PARSEC benchmark show that the bandwidth enhancement and latency reduction are apparent.

  17. South African sign language human-computer interface in the context of the national accessibility portal

    CSIR Research Space (South Africa)

    Olivrin, GJ

    2006-02-01

    Full Text Available example, between a deaf person who can sign and an able person or a person with a different disability who cannot sign). METHODOLOGY A signing avatar is set up to work together with a chatterbot. The chatterbot is a natural language dialogue interface... are then offered in sign language as the replies are interpreted by a signing avatar, a living character that can reproduce human-like gestures and expressions. To make South African Sign Language (SASL) available digitally, computational models of the language...

  18. Computers in the Teaching of English as a Foreign Language: Access to the Diversity of Textual Genres and Language Skills

    Science.gov (United States)

    Dos Santos, Roberto-Márcio; Sobrinho, Jerônimo Coura

    In the area of language teaching both language skills and textual genres can be worked with simultaneously (thus responding to the Brazilian Curricular Parameters and to the trends in contemporary education, which emphasize contextualized teaching) by means of computers. Computers can make the teaching process dynamic and rich, since they enable the access to the foreign language through virtual environments, which creates a larger number of learning contexts, with all their specific vocabulary and linguistic features in real communication. This study focuses on possible applications of this kind of approach. The computer online is a resource of diverse textual genres and can be an important tool in the language classroom as well as an access to authentic material produced in contextualized practice close to real-life communication. On the other hand, all these materials must be appropriately used without ever worshipping the technology as if it were a miraculous solution. After all, the professional pedagogic skills of the teacher should never be forgotten or taken for granted. In this study, a series of interviews with teachers was carried out - both with Brazilian teachers of the public sector (basic education) and language institutes (private English courses) as well as teacher trainers (university professors), in order to verify if the teachers were prepared to work with informatics in teaching practices, and check the professionals’ views on the subject. The ideas of Maingueneau and Marcuschi about textual genres are a theoretical base in this work, besides the concept of cognitive economy. The text and its typology are focused here as the basic material for teaching English, through digital technologies and hypermedia. The study is also based on Sharma and Barrett’s notion of blended learning as a balanced combination of technological resources and traditional practices in the classroom. Thus, this is an attempt to investigate the relevance of

  19. Cortical excitability correlates with the event-related desynchronization during brain-computer interface control

    Science.gov (United States)

    Daly, Ian; Blanchard, Caroline; Holmes, Nicholas P.

    2018-04-01

    Objective. Brain-computer interfaces (BCIs) based on motor control have been suggested as tools for stroke rehabilitation. Some initial successes have been achieved with this approach, however the mechanism by which they work is not yet fully understood. One possible part of this mechanism is a, previously suggested, relationship between the strength of the event-related desynchronization (ERD), a neural correlate of motor imagination and execution, and corticospinal excitability. Additionally, a key component of BCIs used in neurorehabilitation is the provision of visual feedback to positively reinforce attempts at motor control. However, the ability of visual feedback of the ERD to modulate the activity in the motor system has not been fully explored. Approach. We investigate these relationships via transcranial magnetic stimulation delivered at different moments in the ongoing ERD related to hand contraction and relaxation during BCI control of a visual feedback bar. Main results. We identify a significant relationship between ERD strength and corticospinal excitability, and find that our visual feedback does not affect corticospinal excitability. Significance. Our results imply that efforts to promote functional recovery in stroke by targeting increases in corticospinal excitability may be aided by accounting for the time course of the ERD.

  20. Bone mineral density and computer tomographic measurements in correlation with failure strength of equine metacarpal bones

    Directory of Open Access Journals (Sweden)

    Péter Tóth

    2014-01-01

    Full Text Available Information regarding bone mineral density and fracture characteristics of the equine metacarpus are lacking. The aim of this study was to characterize the relationship between mechanical properties of the equine metacarpal bone and its biomechanical and morphometric properties. Third metacarpal bones were extracted from horses euthanized unrelated to musculoskeletal conditions. In total, bone specimens from 26 front limbs of 13 horses (7.8 ± 5.8 years old including Lipizzaner (n = 5, Hungarian Warmblood (n = 2, Holsteiner (n = 2, Thoroughbred (n = 1, Hungarian Sporthorse (n = 1, Friesian (n = 1, and Shagya Arabian (n = 1 were collected. The horses included 7 mares, 4 stallions and 2 geldings. Assessment of the bone mineral density of the whole bone across four specific regions of interest was performed using dual-energy X-ray absorptiometry. The bones were scanned using a computer tomographic scanner to measure cross-sectional morphometric properties such as bone mineral density and cross-sectional dimensions including cortical area and cortical width. Mechanical properties (breaking force, bending strength, elastic modulus were determined by a 3-point bending test. Significant positive linear correlations were found between the breaking force and bone mineral density of the entire third metacarpal bones (P P P in vivo investigations.

  1. Computational time-resolved and resonant x-ray scattering of strongly correlated materials

    Energy Technology Data Exchange (ETDEWEB)

    Bansil, Arun [Northeastern Univ., Boston, MA (United States)

    2016-11-09

    Basic-Energy Sciences of the Department of Energy (BES/DOE) has made large investments in x-ray sources in the U.S. (NSLS-II, LCLS, NGLS, ALS, APS) as powerful enabling tools for opening up unprecedented new opportunities for exploring properties of matter at various length and time scales. The coming online of the pulsed photon source, literally allows us to see and follow the dynamics of processes in materials at their natural timescales. There is an urgent need therefore to develop theoretical methodologies and computational models for understanding how x-rays interact with matter and the related spectroscopies of materials. The present project addressed aspects of this grand challenge of x-ray science. In particular, our Collaborative Research Team (CRT) focused on developing viable computational schemes for modeling x-ray scattering and photoemission spectra of strongly correlated materials in the time-domain. The vast arsenal of formal/numerical techniques and approaches encompassed by the members of our CRT were brought to bear through appropriate generalizations and extensions to model the pumped state and the dynamics of this non-equilibrium state, and how it can be probed via x-ray absorption (XAS), emission (XES), resonant and non-resonant x-ray scattering, and photoemission processes. We explored the conceptual connections between the time-domain problems and other second-order spectroscopies, such as resonant inelastic x-ray scattering (RIXS) because RIXS may be effectively thought of as a pump-probe experiment in which the incoming photon acts as the pump, and the fluorescent decay is the probe. Alternatively, when the core-valence interactions are strong, one can view K-edge RIXS for example, as the dynamic response of the material to the transient presence of a strong core-hole potential. Unlike an actual pump-probe experiment, here there is no mechanism for adjusting the time-delay between the pump and the probe. However, the core hole

  2. Nonequilibrium self-energy functional theory. Accessing the real-time dynamics of strongly correlated fermionic lattice systems

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, Felix

    2016-07-05

    The self-energy functional theory (SFT) is extended to the nonequilibrium case and applied to the real-time dynamics of strongly correlated lattice-fermions. Exploiting the basic structure of the well established equilibrium theory the entire formalism is reformulated in the language of Keldysh-Matsubara Green's functions. To this end, a functional of general nonequilibrium self-energies is constructed which is stationary at the physical point where it moreover yields the physical grand potential of the initial thermal state. Nonperturbative approximations to the full self-energy can be constructed by reducing the original lattice problem to smaller reference systems and varying the functional on the space of the respective trial self-energies, which are parametrized by the reference system's one-particle parameters. Approximations constructed in this way can be shown to respect the macroscopic conservation laws related to the underlying symmetries of the original lattice model. Assuming thermal equilibrium, the original SFT is recovered from the extended formalism. However, in the general case, the nonequilibrium variational principle comprises functional derivatives off the physical parameter space. These can be carried out analytically to derive inherently causal conditional equations for the optimal physical parameters of the reference system and a computationally realizable propagation scheme is set up. As a benchmark for the numerical implementation the variational cluster approach is applied to the dynamics of a dimerized Hubbard model after fast ramps of its hopping parameters. Finally, the time-evolution of a homogeneous Hubbard model after sudden quenches and ramps of the interaction parameter is studied by means of a dynamical impurity approximation with a single bath site. Sharply separated by a critical interaction at which fast relaxation to a thermal final state is observed, two differing response regimes can be distinguished, where the

  3. Clear cell chondrosarcoma: radiographic, computed tomographic, and magnetic resonance findings in 34 patients with pathologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Mark S.; Koyama, Takashi; Swee, Ronald G.; Inwards, Carrie Y. [Department of Radiology, Mayo Clinic, 200 First Street SW, MN 55905, Rochester (United States)

    2003-12-01

    To describe the radiographic features of clear cell chondrosarcoma (CCCS), including the computed tomographic (CT) and magnetic resonance (MR) findings, and to correlate them with the histopathologic findings. A retrospective review was carried out of 72 patients with histopathologically confirmed CCCS. Imaging studies were available for 34 patients: conventional radiographs (n=28), CT scans (n=14), and MR images (n=15). Radiographic studies were reviewed by three radiologists who rendered a consensus opinion; the studies were correlated with the histopathologic findings. Of the 34 patients with imaging studies, 30 were male and 4 were female (mean age 38.6 years; range 11-74 years). Twenty-two lesions were in long bones (15, proximal femur; 1, distal femur; 1, proximal tibia; 5, proximal humerus) and 11 were in flat bones (5, vertebra; 4, rib; 1, scapula; 1, innominate). One lesion occurred in the tarsal navicular bone. Typically, long bone lesions were located in the epimetaphysis (19/22) and were lucent with a well-defined sclerotic margin and no cortical destruction or periosteal new bone formation. More than one-third of the long bone lesions contained matrix mineralization with a characteristic chondroid appearance. Pathologic fractures were present in six long bone lesions (4, humerus; 2, femur). Lesions in the proximal humerus were more likely to have indistinct margins (4/5) and extend into the diaphysis. Flat bone lesions were typically lytic and expansile and occasionally demonstrated areas of cortical disruption. Typically, matrix mineralization, when present, was amorphous. MR imaging, when available, was superior to conventional radiographs for demonstrating the intramedullary extent of a lesion as well as soft tissue extension. CT images better delineated the presence of cortical destruction and the character of matrix mineralization patterns. CCCS lesions were typically low signal intensity on T1-weighted images and moderately or significantly

  4. Clear cell chondrosarcoma: radiographic, computed tomographic, and magnetic resonance findings in 34 patients with pathologic correlation

    International Nuclear Information System (INIS)

    Collins, Mark S.; Koyama, Takashi; Swee, Ronald G.; Inwards, Carrie Y.

    2003-01-01

    To describe the radiographic features of clear cell chondrosarcoma (CCCS), including the computed tomographic (CT) and magnetic resonance (MR) findings, and to correlate them with the histopathologic findings. A retrospective review was carried out of 72 patients with histopathologically confirmed CCCS. Imaging studies were available for 34 patients: conventional radiographs (n=28), CT scans (n=14), and MR images (n=15). Radiographic studies were reviewed by three radiologists who rendered a consensus opinion; the studies were correlated with the histopathologic findings. Of the 34 patients with imaging studies, 30 were male and 4 were female (mean age 38.6 years; range 11-74 years). Twenty-two lesions were in long bones (15, proximal femur; 1, distal femur; 1, proximal tibia; 5, proximal humerus) and 11 were in flat bones (5, vertebra; 4, rib; 1, scapula; 1, innominate). One lesion occurred in the tarsal navicular bone. Typically, long bone lesions were located in the epimetaphysis (19/22) and were lucent with a well-defined sclerotic margin and no cortical destruction or periosteal new bone formation. More than one-third of the long bone lesions contained matrix mineralization with a characteristic chondroid appearance. Pathologic fractures were present in six long bone lesions (4, humerus; 2, femur). Lesions in the proximal humerus were more likely to have indistinct margins (4/5) and extend into the diaphysis. Flat bone lesions were typically lytic and expansile and occasionally demonstrated areas of cortical disruption. Typically, matrix mineralization, when present, was amorphous. MR imaging, when available, was superior to conventional radiographs for demonstrating the intramedullary extent of a lesion as well as soft tissue extension. CT images better delineated the presence of cortical destruction and the character of matrix mineralization patterns. CCCS lesions were typically low signal intensity on T1-weighted images and moderately or significantly

  5. Towards a Computable Data Corpus of Temporal Correlations between Drug Administration and Lab Value Changes.

    Directory of Open Access Journals (Sweden)

    Axel Newe

    Full Text Available The analysis of electronic health records for an automated detection of adverse drug reactions is an approach to solve the problems that arise from traditional methods like spontaneous reporting or manual chart review. Algorithms addressing this task should be modeled on the criteria for a standardized case causality assessment defined by the World Health Organization. One of these criteria is the temporal relationship between drug intake and the occurrence of a reaction or a laboratory test abnormality. Appropriate data that would allow for developing or validating related algorithms is not publicly available, though.In order to provide such data, retrospective routine data of drug administrations and temporally corresponding laboratory observations from a university clinic were extracted, transformed and evaluated by experts in terms of a reasonable time relationship between drug administration and lab value alteration.The result is a data corpus of 400 episodes of normalized laboratory parameter values in temporal context with drug administrations. Each episode has been manually classified whether it contains data that might indicate a temporal correlation between the drug administration and the change of the lab value course, whether such a change is not observable or whether a decision between those two options is not possible due to the data. In addition, each episode has been assigned a concordance value which indicates how difficult it is to assess. This is the first open data corpus of a computable ground truth of temporal correlations between drug administration and lab value alterations.The main purpose of this data corpus is the provision of data for further research and the provision of a ground truth which allows for comparing the outcome of other assessments of this data with the outcome of assessments made by human experts. It can serve as a contribution towards systematic, computerized ADR detection in retrospective data. With

  6. The benefit of non contrast-enhanced magnetic resonance angiography for predicting vascular access surgery outcome: a computer model perspective.

    Directory of Open Access Journals (Sweden)

    Maarten A G Merkx

    Full Text Available INTRODUCTION: Vascular access (VA surgery, a prerequisite for hemodialysis treatment of end-stage renal-disease (ESRD patients, is hampered by complication rates, which are frequently related to flow enhancement. To assist in VA surgery planning, a patient-specific computer model for postoperative flow enhancement was developed. The purpose of this study is to assess the benefit of non contrast-enhanced magnetic resonance angiography (NCE-MRA data as patient-specific geometrical input for the model-based prediction of surgery outcome. METHODS: 25 ESRD patients were included in this study. All patients received a NCE-MRA examination of the upper extremity blood vessels in addition to routine ultrasound (US. Local arterial radii were assessed from NCE-MRA and converted to model input using a linear fit per artery. Venous radii were determined with US. The effect of radius measurement uncertainty on model predictions was accounted for by performing Monte-Carlo simulations. The resulting flow prediction interval of the computer model was compared with the postoperative flow obtained from US. Patients with no overlap between model-based prediction and postoperative measurement were further analyzed to determine whether an increase in geometrical detail improved computer model prediction. RESULTS: Overlap between postoperative flows and model-based predictions was obtained for 71% of patients. Detailed inspection of non-overlapping cases revealed that the geometrical details that could be assessed from NCE-MRA explained most of the differences, and moreover, upon addition of these details in the computer model the flow predictions improved. CONCLUSIONS: The results demonstrate clearly that NCE-MRA does provide valuable geometrical information for VA surgery planning. Therefore, it is recommended to use this modality, at least for patients at risk for local or global narrowing of the blood vessels as well as for patients for whom an US-based model

  7. Fencing network direct memory access data transfers in a parallel active messaging interface of a parallel computer

    Science.gov (United States)

    Blocksome, Michael A.; Mamidala, Amith R.

    2015-07-07

    Fencing direct memory access (`DMA`) data transfers in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI including data communications endpoints, each endpoint including specifications of a client, a context, and a task, the endpoints coupled for data communications through the PAMI and through DMA controllers operatively coupled to a deterministic data communications network through which the DMA controllers deliver data communications deterministically, including initiating execution through the PAMI of an ordered sequence of active DMA instructions for DMA data transfers between two endpoints, effecting deterministic DMA data transfers through a DMA controller and the deterministic data communications network; and executing through the PAMI, with no FENCE accounting for DMA data transfers, an active FENCE instruction, the FENCE instruction completing execution only after completion of all DMA instructions initiated prior to execution of the FENCE instruction for DMA data transfers between the two endpoints.

  8. A Computational Method based on Radio Frequency Technologies for the Analysis of Accessibility of Disabled People in Sustainable Cities

    Directory of Open Access Journals (Sweden)

    Virgilio Gilart-Iglesias

    2015-11-01

    Full Text Available The sustainability strategy in urban spaces arises from reflecting on how to achieve a more habitable city and is materialized in a series of sustainable transformations aimed at humanizing different environments so that they can be used and enjoyed by everyone without exception and regardless of their ability. Modern communication technologies allow new opportunities to analyze efficiency in the use of urban spaces from several points of view: adequacy of facilities, usability, and social integration capabilities. The research presented in this paper proposes a method to perform an analysis of movement accessibility in sustainable cities based on radio frequency technologies and the ubiquitous computing possibilities of the new Internet of Things paradigm. The proposal can be deployed in both indoor and outdoor environments to check specific locations of a city. Finally, a case study in a controlled context has been simulated to validate the proposal as a pre-deployment step in urban environments.

  9. Intelligent computer aided training systems in the real world: Making the technology accessible to the educational mainstream

    Science.gov (United States)

    Kovarik, Madeline

    1993-01-01

    Intelligent computer aided training systems hold great promise for the application of this technology to mainstream education and training. Yet, this technology, which holds such a vast potential impact for the future of education and training, has had little impact beyond the enclaves of government research labs. This is largely due to the inaccessibility of the technology to those individuals in whose hands it can have the greatest impact, teachers and educators. Simply throwing technology at an educator and expecting them to use it as an effective tool is not the answer. This paper provides a background into the use of technology as a training tool. MindLink, developed by HyperTech Systems, provides trainers with a powerful rule-based tool that can be integrated directly into a Windows application. By embedding expert systems technology it becomes more accessible and easier to master.

  10. Cone-Beam Computed Tomography Correlates with Conventional Helical Computed Tomography in Evaluation of Lipiodol Accumulation in HCC after Chemoembolization.

    Directory of Open Access Journals (Sweden)

    Toru Ishikawa

    Full Text Available The amount of drug-loaded lipiodol in an HCC tumor post-transarterial chemoembolization (TACE correlates with the risk of local tumor recurrence. Lipiodol enhancement of a tumor on conventional CT, measured in Hounsfield units (HU, can predict tumor response. Here we investigate whether cone-beam CT (CBCT can also be used to predict tumor response, providing the benefit of being able to optimize the patient's treatment plan intra-procedurally.A total of 82 HCC nodules (82 patients, ≤5 cm in diameter, were treated with balloon-occluded TACE using miriplatin between December 2013 and November 2014. For each patient, both CBCT and conventional CT images were obtained post-TACE. The degree of correlation between CBCT and conventional CT was determined by comparing identical regions of interest for each imaging modality using pixel values.The pixel values from conventional CT and CBCT were highly correlated, with a Pearson correlation coefficient of 0.912 (p<0.001. The location of the nodules within the liver did not affect the results; the correlation coefficient was 0.891 (p<0.001 for the left lobe and 0.926 (p<0.001 for the right lobe. The mean pixel value for conventional CT was 439 ± 279 HU, and the mean pixel value for CBCT was 416 ± 311 HU.CBCT may be used as a substitute for conventional CT to quantitatively evaluate the amount of drug-loaded lipiodol within an HCC nodule and, hence, the efficacy of TACE treatment. The major benefit of using CBCT is the ability to predict the likelihood of local recurrence intra-procedurally, enabling subsequent treatment optimization.

  11. Three-dimensional evaluation of human jaw bone microarchitecture: correlation between the microarchitectural parameters of cone beam computed tomography and micro-computer tomography.

    Science.gov (United States)

    Kim, Jo-Eun; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul; Huh, Kyung-Hoe

    2015-12-01

    To evaluate the potential feasibility of cone beam computed tomography (CBCT) in the assessment of trabecular bone microarchitecture. Sixty-eight specimens from four pairs of human jaw were scanned using both micro-computed tomography (micro-CT) of 19.37-μm voxel size and CBCT of 100-μm voxel size. The correlation of 3-dimensional parameters between CBCT and micro-CT was evaluated. All parameters, except bone-specific surface and trabecular thickness, showed linear correlations between the 2 imaging modalities (P < .05). Among the parameters, bone volume, percent bone volume, trabecular separation, and degree of anisotropy (DA) of CBCT images showed strong correlations with those of micro-CT images. DA showed the strongest correlation (r = 0.693). Most microarchitectural parameters from CBCT were correlated with those from micro-CT. Some microarchitectural parameters, especially DA, could be used as strong predictors of bone quality in the human jaw. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. The Effect of Computer-Based Self-Access Learning on Weekly Vocabulary Test Scores

    Directory of Open Access Journals (Sweden)

    Jordan Dreyer

    2014-09-01

    Full Text Available This study sets out to clarify the effectiveness of using an online vocabulary study tool, Quizlet, in an urban high school language arts class. Previous similar studies have mostly dealt with English Language Learners in college settings (Chui, 2013, and were therefore not directed at the issue self-efficacy that is at the heart of the problem of urban high school students in America entering remedial writing programs (Rose, 1989. The study involves 95 students over the course of 14 weeks. Students were tested weekly and were asked to use the Quizlet program in their own free time. The result of this optional involvement was that many students did not participate in the treatment and therefore acted as an elective control group. The resultant data collected shows a strong correlation between the use of an online vocabulary review program and short-term vocabulary retention. The study also showed that students who paced themselves and spread out their study sessions outperformed those students who used the program only for last minute “cram sessions.” The implications of the study are that students who take advantage of tools outside of the classroom are able to out perform their peers. The results are also in line with the call to include technology in the Basic Writing classroom not simply as a tool, but as a “form of discourse” (Jonaitis, 2012. Weekly vocabulary tests, combined with the daily online activity as reported by Quizlet, show that: 1 utilizing the review software improved the scores of most students, 2 those students who used Quizlet to review more than a single time (i.e., several days before the test outperformed those who only used the product once, and 3 students who professed proficiency with the “notebook” system of vocabulary learning appeared not to need the treatment.

  13. Computation of antenna pattern correlation and MIMO performance by means of surface current distribution and spherical wave theory

    Directory of Open Access Journals (Sweden)

    O. Klemp

    2006-01-01

    Full Text Available In order to satisfy the stringent demand for an accurate prediction of MIMO channel capacity and diversity performance in wireless communications, more effective and suitable models that account for real antenna radiation behavior have to be taken into account. One of the main challenges is the accurate modeling of antenna correlation that is directly related to the amount of channel capacity or diversity gain which might be achieved in multi element antenna configurations. Therefore spherical wave theory in electromagnetics is a well known technique to express antenna far fields by means of a compact field expansion with a reduced number of unknowns that was recently applied to derive an analytical approach in the computation of antenna pattern correlation. In this paper we present a novel and efficient computational technique to determine antenna pattern correlation based on the evaluation of the surface current distribution by means of a spherical mode expansion.

  14. Elucidation and Optimization of Resistive Random Access Memory Switching Behavior for Advanced Computing Applications

    Science.gov (United States)

    Alamgir, Zahiruddin

    RRAM has recently emerged as a strong candidate for non-volatile memory (NVM). Beyond memory applications, RRAM holds promise for use in performing logic functions, mimicking neuromorphic activities, enabling multi-level switching, and as one of the key elements of hardware based encryption or signal processing systems. It has been shown previously that RRAM resistance levels can be changed by adjusting compliance current or voltage level. This characteristic makes RRAM suitable for use in setting the synaptic weight in neuromorphic computing circuits. RRAM is also considered as a key element in hardware encryption systems, to produce unique and reproducible signals. However, a key challenge to implement RRAM in these applications is significant cycle to cycle performance variability. We sought to develop RRAM that can be tuned to different resistance levels gradually, with high reliability, and low variability. To achieve this goal, we focused on elucidating the conduction mechanisms underlying the resistive switching behavior for these devices. Electrical conduction mechanisms were determined by curve fitting I-V data using different current conduction equations. Temperature studies were also performed to corroborate these data. It was found that Schottky barrier height and width modulation was one of the key parameters that could be tuned to achieve different resistance levels, and for switching resistance states, primarily via oxygen vacancy movement. Oxygen exchange layers with different electronegativity were placed between top electrode and the oxide layer of TaOx devices to determine the effect of oxygen vacancy concentrations and gradients in these devices. It was found that devices with OELs with lower electronegativity tend to yield greater separation in the OFF vs. ON state resistance levels. As an extension of this work, TaOx based RRAM with Hf as the OEL was fabricated and could be tuned to different resistance level using pulse width and height

  15. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction During the past six months, Computing participated in the STEP09 exercise, had a major involvement in the October exercise and has been working with CMS sites on improving open issues relevant for data taking. At the same time operations for MC production, real data reconstruction and re-reconstructions and data transfers at large scales were performed. STEP09 was successfully conducted in June as a joint exercise with ATLAS and the other experiments. It gave good indication about the readiness of the WLCG infrastructure with the two major LHC experiments stressing the reading, writing and processing of physics data. The October Exercise, in contrast, was conducted as an all-CMS exercise, where Physics, Computing and Offline worked on a common plan to exercise all steps to efficiently access and analyze data. As one of the major results, the CMS Tier-2s demonstrated to be fully capable for performing data analysis. In recent weeks, efforts were devoted to CMS Computing readiness. All th...

  16. A flowsheet model of a coal-fired MHD/steam combined electricity generating cycle, using the access computer model

    International Nuclear Information System (INIS)

    Davison, J.E.; Eldershaw, C.E.

    1992-01-01

    This document forms the final report on a study of a coal-fired magnetohydrodynamic (MHD)/steam electric power generation system carried out by British Coal Corporation for the Commission of the European Communities. The study objective was to provide mass and energy balances and overall plant efficiency predictions for MHD to assist the Commission in their evaluation of advanced power generation technologies. In early 1990 the British Coal Corporation completed a study for the Commission in which a computer flowsheet modelling package was used to predict the performance of a conceptual air blown MHD plant. Since that study was carried out increasing emphasis has been placed on the possible need to reduce CO 2 emissions to counter the so-called greenhouse effect. Air blown MHD could greatly reduce CO 2 emissions per KWh by virtue of its high thermal efficiency. However, if even greater reductions in CO 2 emissions were required the CO 2 produced by coal combustion may have to be disposed of, for example into the deep ocean or underground caverns. To achieve this at minimum cost a concentrated CO 2 flue gas would be required. This could be achieved in an MHD plant by using a mixture of high purity oxygen and recycled CO 2 flue gas in the combustor. To assess this plant concept the European Commission awarded British Coal a contract to produce performance predictions using the access computer program

  17. The correlation between a passion for computer games and the school performance of younger schoolchildren.

    OpenAIRE

    Maliy D.V.

    2015-01-01

    Today computer games occupy a significant place in children’s lives and fundamentally affect the process of the formation and development of their personalities. A number of present-day researchers assert that computer games have a developmental effect on players. Others share the point of view that computer games have negative effects on the cognitive and emotional spheres of a child and claim that children with low self-esteem who neglect their schoolwork and have difficulties in communicat...

  18. The correlation between a passion for computer games and the school performance of younger schoolchildren

    OpenAIRE

    KULIKOVA TATYANA I.; MALIY DMITRY V.

    2015-01-01

    Today computer games occupy a significant place in children’s lives and fundamentally affect the process of the formation and development of their personalities. A number of present-day researchers assert that computer games have a developmental effect on players. Others share the point of view that computer games have negative effects on the cognitive and emotional spheres of a child and claim that children with low self-esteem who neglect their schoolwork and have difficulties in communicat...

  19. Morphological measurements in computed tomography correlate with airflow obstruction in chronic obstructive pulmonary disease: systematic review and meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Xie, XueQian; Oudkerk, Matthijs; Vliegenthart, Rozemarijn [University of Groningen, University Medical Center Groningen, Center for Medical Imaging-North East Netherlands (CMI-NEN), Department of Radiology, Hanzeplein 1, P.O. Box 30.001, RB, Groningen (Netherlands); Jong, Pim A. de [University Medical Center Utrecht, University of Utrecht, Department of Radiology, Heidelberglaan 100, P.O. Box 85.500, CX, Utrecht (Netherlands); Wang, Ying [Tianjin Medical University General Hospital, Department of Radiology, Tianjin (China); Hacken, Nick H.T. ten [University of Groningen, University Medical Center Groningen, Department of Pulmonary Diseases, Hanzeplein 1, P.O. Box 30.001, RB, Groningen (Netherlands); Miao, Jingtao; Zhang, GuiXiang [Shanghai Jiao Tong University Affiliated First People' s Hospital, Department of Radiology, Shanghai (China); Bock, Geertruida H. de [University of Groningen, University Medical Center Groningen, Department of Epidemiology, Hanzeplein 1, P.O. Box 30.001, RB, Groningen (Netherlands)

    2012-10-15

    To determine the correlation between CT measurements of emphysema or peripheral airways and airflow obstruction in chronic obstructive pulmonary disease (COPD). PubMed, Embase and Web of Knowledge were searched from 1976 to 2011. Two reviewers independently screened 1,763 citations to identify articles that correlated CT measurements to airflow obstruction parameters of the pulmonary function test in COPD patients, rated study quality and extracted information. Three CT measurements were accessed: lung attenuation area percentage < -950 Hounsfield units, mean lung density and airway wall area percentage. Two airflow obstruction parameters were accessed: forced expiratory volume in the first second as percentage from predicted (FEV{sub 1} %pred) and FEV{sub 1} divided by the forced volume vital capacity. Seventy-nine articles (9,559 participants) were included in the systematic review, demonstrating different methodologies, measurements and CT airflow obstruction correlations. There were 15 high-quality articles (2,095 participants) in the meta-analysis. The absolute pooled correlation coefficients ranged from 0.48 (95 % CI, 0.40 to 0.54) to 0.65 (0.58 to 0.71) for inspiratory CT and 0.64 (0.53 to 0.72) to 0.73 (0.63 to 0.80) for expiratory CT. CT measurements of emphysema or peripheral airways are significantly related to airflow obstruction in COPD patients. CT provides a morphological method to investigate airway obstruction in COPD. (orig.)

  20. Soft computing analysis of the possible correlation between temporal and energy release patterns in seismic activity

    Science.gov (United States)

    Konstantaras, Anthony; Katsifarakis, Emmanouil; Artzouxaltzis, Xristos; Makris, John; Vallianatos, Filippos; Varley, Martin

    2010-05-01

    This paper is a preliminary investigation of the possible correlation of temporal and energy release patterns of seismic activity involving the preparation processes of consecutive sizeable seismic events [1,2]. The background idea is that during periods of low-level seismic activity, stress processes in the crust accumulate energy at the seismogenic area whilst larger seismic events act as a decongesting mechanism releasing considerable energy [3,4]. A dynamic algorithm is being developed aiming to identify and cluster pre- and post- seismic events to the main earthquake following on research carried out by Zubkov [5] and Dobrovolsky [6,7]. This clustering technique along with energy release equations dependent on Richter's scale [8,9] allow for an estimate to be drawn regarding the amount of the energy being released by the seismic sequence. The above approach is being implemented as a monitoring tool to investigate the behaviour of the underlying energy management system by introducing this information to various neural [10,11] and soft computing models [1,12,13,14]. The incorporation of intelligent systems aims towards the detection and simulation of the possible relationship between energy release patterns and time-intervals among consecutive sizeable earthquakes [1,15]. Anticipated successful training of the imported intelligent systems may result in a real-time, on-line processing methodology [1,16] capable to dynamically approximate the time-interval between the latest and the next forthcoming sizeable seismic event by monitoring the energy release process in a specific seismogenic area. Indexing terms: pattern recognition, long-term earthquake precursors, neural networks, soft computing, earthquake occurrence intervals References [1] Konstantaras A., Vallianatos F., Varley M.R. and Makris J. P.: ‘Soft computing modelling of seismicity in the southern Hellenic arc', IEEE Geoscience and Remote Sensing Letters, vol. 5 (3), pp. 323-327, 2008 [2] Eneva M. and

  1. Correlation between Academic and Skills-Based Tests in Computer Networks

    Science.gov (United States)

    Buchanan, William

    2006-01-01

    Computing-related programmes and modules have many problems, especially related to large class sizes, large-scale plagiarism, module franchising, and an increased requirement from students for increased amounts of hands-on, practical work. This paper presents a practical computer networks module which uses a mixture of online examinations and a…

  2. Cognitive Correlates of Performance in Algorithms in a Computer Science Course for High School

    Science.gov (United States)

    Avancena, Aimee Theresa; Nishihara, Akinori

    2014-01-01

    Computer science for high school faces many challenging issues. One of these is whether the students possess the appropriate cognitive ability for learning the fundamentals of computer science. Online tests were created based on known cognitive factors and fundamental algorithms and were implemented among the second grade students in the…

  3. SIEX3: A correlated computer code for prediction of fast reactor mixed oxide fuel and blanket pin performance

    International Nuclear Information System (INIS)

    Baker, R.B.; Wilson, D.R.

    1986-04-01

    The SIEX3 computer program was developed to calculate the fuel and cladding performance of oxide fuel and oxide blanket pins irradiated in the fast neutron environment of a liquid metal cooled reactor. The code is uniquely designed to be accurate yet quick running and use a minimum of computer core storage. This was accomplished through the correlation of physically based models to very large data bases of irradiation test results. Data from over 200 fuel pins and over 800 transverse fuel microscopy samples were used in the calibrations

  4. Simulation-based computation of the workload correlation function in a Lévy-driven queue

    NARCIS (Netherlands)

    Glynn, P.W.; Mandjes, M.

    2011-01-01

    In this paper we consider a single-server queue with Lévy input, and, in particular, its workload process (Qt)t≥0, focusing on its correlation structure. With the correlation function defined as r(t):= cov(Q0, Qt) / varQ0 (assuming that the workload process is in stationarity at time 0), we first

  5. Simulation-based computation of the workload correlation function in a Levy-driven queue

    NARCIS (Netherlands)

    P. Glynn; M.R.H. Mandjes (Michel)

    2009-01-01

    htmlabstractIn this paper we consider a single-server queue with Levy input, and in particular its workload process (Q_t), focusing on its correlation structure. With the correlation function defined as r(t) := Cov(Q_0, Q_t)/Var Q_0 (assuming the workload process is in stationarity at time 0), we

  6. Simulation-based computation of the workload correlation function in a Lévy-driven queue

    NARCIS (Netherlands)

    P. Glynn; M.R.H. Mandjes (Michel)

    2010-01-01

    htmlabstractIn this paper we consider a single-server queue with Levy input, and in particular its workload process (Q_t), focusing on its correlation structure. With the correlation function defined as r(t) := Cov(Q_0,Q_t)/Var(Q_0) (assuming the workload process is in stationarity at time 0), we

  7. May–Thurner syndrome: Correlation between digital subtraction and computed tomography venography

    Directory of Open Access Journals (Sweden)

    Ying-Sheng Kuo

    2015-04-01

    Conclusion: The cross-sectional area ratio and diameter ratio in CTV correlate with the reflux start-up time in DSV. For May–Thurner syndrome, both CTV and DSV provide essential information for diagnosis and evaluation of the disease. The positive correlation between anatomical and hemodynamic properties corresponds with the underlying pathophysiology.

  8. Visual computed tomographic scoring of emphysema and its correlation with its diagnostic electrocardiographic sign: the frontal P vector.

    Science.gov (United States)

    Chhabra, Lovely; Sareen, Pooja; Gandagule, Amit; Spodick, David H

    2012-03-01

    Verticalization of the frontal P vector in patients older than 45 years is virtually diagnostic of pulmonary emphysema (sensitivity, 96%; specificity, 87%). We investigated the correlation of P vector and the computed tomographic visual score of emphysema (VSE) in patients with established diagnosis of chronic obstructive pulmonary disease/emphysema. High-resolution computed tomographic scans of 26 patients with emphysema (age, >45 years) were reviewed to assess the type and extent of emphysema using the subjective visual scoring. Electrocardiograms were independently reviewed to determine the frontal P vector. The P vector and VSE were compared for statistical correlation. Both P vector and VSE were also directly compared with the forced expiratory volume at 1 second. The VSE and the orientation of the P vector (ÂP) had an overall significant positive correlation (r = +0.68; P = .0001) in all patients, but the correlation was very strong in patients with predominant lower-lobe emphysema (r = +0.88; P = .0004). Forced expiratory volume at 1 second and ÂP had almost a linear inverse correlation in predominant lower-lobe emphysema (r = -0.92; P vertical ÂP and predominant lower-lobe emphysema reflects severe obstructive lung dysfunction. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Correlation of the clinical and physical image quality in chest radiography for average adults with a computed radiography imaging system.

    Science.gov (United States)

    Moore, C S; Wood, T J; Beavis, A W; Saunderson, J R

    2013-07-01

    The purpose of this study was to examine the correlation between the quality of visually graded patient (clinical) chest images and a quantitative assessment of chest phantom (physical) images acquired with a computed radiography (CR) imaging system. The results of a previously published study, in which four experienced image evaluators graded computer-simulated postero-anterior chest images using a visual grading analysis scoring (VGAS) scheme, were used for the clinical image quality measurement. Contrast-to-noise ratio (CNR) and effective dose efficiency (eDE) were used as physical image quality metrics measured in a uniform chest phantom. Although optimal values of these physical metrics for chest radiography were not derived in this work, their correlation with VGAS in images acquired without an antiscatter grid across the diagnostic range of X-ray tube voltages was determined using Pearson's correlation coefficient. Clinical and physical image quality metrics increased with decreasing tube voltage. Statistically significant correlations between VGAS and CNR (R=0.87, pchest CR images acquired without an antiscatter grid. A statistically significant correlation has been found between the clinical and physical image quality in CR chest imaging. The results support the value of using CNR and eDE in the evaluation of quality in clinical thorax radiography.

  10. Explicitly-correlated ring-coupled-cluster-doubles theory: Including exchange for computations on closed-shell systems

    Energy Technology Data Exchange (ETDEWEB)

    Hehn, Anna-Sophia; Holzer, Christof; Klopper, Wim, E-mail: klopper@kit.edu

    2016-11-10

    Highlights: • Ring-coupled-cluster-doubles approach now implemented with exchange terms. • Ring-coupled-cluster-doubles approach now implemented with F12 functions. • Szabo–Ostlund scheme (SO2) implemented for use in SAPT. • Fast convergence to the limit of a complete basis. • Implementation in the TURBOMOLE program system. - Abstract: Random-phase-approximation (RPA) methods have proven to be powerful tools in electronic-structure theory, being non-empirical, computationally efficient and broadly applicable to a variety of molecular systems including small-gap systems, transition-metal compounds and dispersion-dominated complexes. Applications are however hindered due to the slow basis-set convergence of the electron-correlation energy with the one-electron basis. As a remedy, we present approximate explicitly-correlated RPA approaches based on the ring-coupled-cluster-doubles formulation including exchange contributions. Test calculations demonstrate that the basis-set convergence of correlation energies is drastically accelerated through the explicitly-correlated approach, reaching 99% of the basis-set limit with triple-zeta basis sets. When implemented in close analogy to early work by Szabo and Ostlund [36], the new explicitly-correlated ring-coupled-cluster-doubles approach including exchange has the perspective to become a valuable tool in the framework of symmetry-adapted perturbation theory (SAPT) for the computation of dispersion energies of molecular complexes of weakly interacting closed-shell systems.

  11. bc-GenExMiner 3.0: new mining module computes breast cancer gene expression correlation analyses.

    Science.gov (United States)

    Jézéquel, Pascal; Frénel, Jean-Sébastien; Campion, Loïc; Guérin-Charbonnel, Catherine; Gouraud, Wilfried; Ricolleau, Gabriel; Campone, Mario

    2013-01-01

    We recently developed a user-friendly web-based application called bc-GenExMiner (http://bcgenex.centregauducheau.fr), which offered the possibility to evaluate prognostic informativity of genes in breast cancer by means of a 'prognostic module'. In this study, we develop a new module called 'correlation module', which includes three kinds of gene expression correlation analyses. The first one computes correlation coefficient between 2 or more (up to 10) chosen genes. The second one produces two lists of genes that are most correlated (positively and negatively) to a 'tested' gene. A gene ontology (GO) mining function is also proposed to explore GO 'biological process', 'molecular function' and 'cellular component' terms enrichment for the output lists of most correlated genes. The third one explores gene expression correlation between the 15 telomeric and 15 centromeric genes surrounding a 'tested' gene. These correlation analyses can be performed in different groups of patients: all patients (without any subtyping), in molecular subtypes (basal-like, HER2+, luminal A and luminal B) and according to oestrogen receptor status. Validation tests based on published data showed that these automatized analyses lead to results consistent with studies' conclusions. In brief, this new module has been developed to help basic researchers explore molecular mechanisms of breast cancer. DATABASE URL: http://bcgenex.centregauducheau.fr

  12. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction A large fraction of the effort was focused during the last period into the preparation and monitoring of the February tests of Common VO Computing Readiness Challenge 08. CCRC08 is being run by the WLCG collaboration in two phases, between the centres and all experiments. The February test is dedicated to functionality tests, while the May challenge will consist of running at all centres and with full workflows. For this first period, a number of functionality checks of the computing power, data repositories and archives as well as network links are planned. This will help assess the reliability of the systems under a variety of loads, and identifying possible bottlenecks. Many tests are scheduled together with other VOs, allowing the full scale stress test. The data rates (writing, accessing and transfer¬ring) are being checked under a variety of loads and operating conditions, as well as the reliability and transfer rates of the links between Tier-0 and Tier-1s. In addition, the capa...

  13. COMPUTING

    CERN Multimedia

    I. Fisk

    2013-01-01

    Computing operation has been lower as the Run 1 samples are completing and smaller samples for upgrades and preparations are ramping up. Much of the computing activity is focusing on preparations for Run 2 and improvements in data access and flexibility of using resources. Operations Office Data processing was slow in the second half of 2013 with only the legacy re-reconstruction pass of 2011 data being processed at the sites.   Figure 1: MC production and processing was more in demand with a peak of over 750 Million GEN-SIM events in a single month.   Figure 2: The transfer system worked reliably and efficiently and transferred on average close to 520 TB per week with peaks at close to 1.2 PB.   Figure 3: The volume of data moved between CMS sites in the last six months   The tape utilisation was a focus for the operation teams with frequent deletion campaigns from deprecated 7 TeV MC GEN-SIM samples to INVALID datasets, which could be cleaned up...

  14. COMPUTING

    CERN Multimedia

    I. Fisk

    2012-01-01

      Introduction Computing activity has been running at a sustained, high rate as we collect data at high luminosity, process simulation, and begin to process the parked data. The system is functional, though a number of improvements are planned during LS1. Many of the changes will impact users, we hope only in positive ways. We are trying to improve the distributed analysis tools as well as the ability to access more data samples more transparently.  Operations Office Figure 2: Number of events per month, for 2012 Since the June CMS Week, Computing Operations teams successfully completed data re-reconstruction passes and finished the CMSSW_53X MC campaign with over three billion events available in AOD format. Recorded data was successfully processed in parallel, exceeding 1.2 billion raw physics events per month for the first time in October 2012 due to the increase in data-parking rate. In parallel, large efforts were dedicated to WMAgent development and integrati...

  15. Cranium-brain trauma in computed tomographs - diagnosis and clinical correlation

    International Nuclear Information System (INIS)

    Wrasse, K.

    1982-01-01

    For the successful treatment of intracranial complications in the case of cranium-brain trauma a quick and exact diagnosis is necessary. The goal of this work was to test and evaluate the effectivity of computed tomography for neurotraumatology. Using 565 patients, who were acutely or at one time suffering from a cranium-brain trauma, the high validity of computed tomography for these injuries was proven. The following areas in question were studied with respect to the value of computed tomography in comparison to them: angiography, X-ray diagnostic, echoencephalography, brain scintigraphy, electroencephalography and neurological-psychopathological findings from cranium-brain trauma. Statement possibilities and difficulties of computed tomography are discussed in the cases of the following neurotraumatological diseases: extracranial hematomas; acute cranium-brain traumas; traumatic arachnoidal bleeding; diffuse brain edema; transtentorial herniation and brain contusions. At the end the diagnostic and therapeutic procedures in the case of cranium-brain trauma are presented. (orig.) [de

  16. Computer assisted extraction, merging and correlation of identities with Tracks Inspector

    NARCIS (Netherlands)

    Hofste, Jop; Henseler, Hans; van Keulen, Maurice

    With the pervasiveness of computers and mobile devices, digital forensics becomes more important in law enforcement. Detectives increasingly depend on the scarce support of digital specialists which impedes efficiency of criminal investigations. Tracks Inspector is a commercial solution that enables

  17. Accessibility of nucleic acid-complexed biomolecules to hydroxyl radicals correlates with their conformation: a fluorescence polarization spectroscopy study

    International Nuclear Information System (INIS)

    Makrigiorgos, G.M.; Bump, E.; Huang, C.; Kassis, A.I.; Baranowska-Kortylewicz, J.

    1994-01-01

    A fluorescence methodology has been developed to examine the relationship between the conformational state of specific biomolecules in simple chromatin models and their accessibility to hydroxyl radicals ( . OH). Polylysine and histone H1 were labelled with SECCA, the succinimidyl ester of coumarin-3-carboxylic acid, which generates the fluorescent derivative 7-OH-SECCA following its interaction with radiation-induced . OH in aqueous solution. The fluorescence induced per unit γ-ray dose reflecting the accessibility of . OH to such SECCA-conjugated biomolecules was recorded. The biomolecules were also labelled with the fluorescent derivative 7-OH-SECCA in trace amounts to study their conformation under identical conditions via fluorescence polarization spectroscopy. (author)

  18. A computational approach to measuring the correlation between expertise and social media influence for celebrities on microblogs

    OpenAIRE

    Zhao, Wayne Xin; Liu, Jing; He, Yulan; Lin, Chin Yew; Wen, Ji-Rong

    2016-01-01

    Social media influence analysis, sometimes also called authority detection, aims to rank users based on their influence scores in social media. Existing approaches of social influence analysis usually focus on how to develop effective algorithms to quantize users’ influence scores. They rarely consider a person’s expertise levels which are arguably important to influence measures. In this paper, we propose a computational approach to measuring the correlation between expertise and social medi...

  19. Applying standardized uptake values in gallium-67-citrate single-photon emission computed tomography/computed tomography studies and their correlation with blood test results in representative organs.

    Science.gov (United States)

    Toriihara, Akira; Daisaki, Hiromitsu; Yamaguchi, Akihiro; Yoshida, Katsuya; Isogai, Jun; Tateishi, Ukihide

    2018-05-21

    Recently, semiquantitative analysis using standardized uptake value (SUV) has been introduced in bone single-photon emission computed tomography/computed tomography (SPECT/CT). Our purposes were to apply SUV-based semiquantitative analytic method for gallium-67 (Ga)-citrate SPECT/CT and to evaluate correlation between SUV of physiological uptake and blood test results in representative organs. The accuracy of semiquantitative method was validated using an National Electrical Manufacturers Association body phantom study (radioactivity ratio of sphere : background=4 : 1). Thereafter, 59 patients (34 male and 25 female; mean age, 66.9 years) who had undergone Ga-citrate SPECT/CT were retrospectively enrolled in the study. A mean SUV of physiological uptake was calculated for the following organs: the lungs, right atrium, liver, kidneys, spleen, gluteal muscles, and bone marrow. The correlation between physiological uptakes and blood test results was evaluated using Pearson's correlation coefficient. The phantom study revealed only 1% error between theoretical and actual SUVs in the background, suggesting the sufficient accuracy of scatter and attenuation corrections. However, a partial volume effect could not be overlooked, particularly in small spheres with a diameter of less than 28 mm. The highest mean SUV was observed in the liver (range: 0.44-4.64), followed by bone marrow (range: 0.33-3.60), spleen (range: 0.52-2.12), and kidneys (range: 0.42-1.45). There was no significant correlation between hepatic uptake and liver function, renal uptake and renal function, or bone marrow uptake and blood cell count (P>0.05). The physiological uptake in Ga-citrate SPECT/CT can be represented as SUVs, which are not significantly correlated with corresponding blood test results.

  20. Fast computation of molecular random phase approximation correlation energies using resolution of the identity and imaginary frequency integration

    Science.gov (United States)

    Eshuis, Henk; Yarkony, Julian; Furche, Filipp

    2010-06-01

    The random phase approximation (RPA) is an increasingly popular post-Kohn-Sham correlation method, but its high computational cost has limited molecular applications to systems with few atoms. Here we present an efficient implementation of RPA correlation energies based on a combination of resolution of the identity (RI) and imaginary frequency integration techniques. We show that the RI approximation to four-index electron repulsion integrals leads to a variational upper bound to the exact RPA correlation energy if the Coulomb metric is used. Auxiliary basis sets optimized for second-order Møller-Plesset (MP2) calculations are well suitable for RPA, as is demonstrated for the HEAT [A. Tajti et al., J. Chem. Phys. 121, 11599 (2004)] and MOLEKEL [F. Weigend et al., Chem. Phys. Lett. 294, 143 (1998)] benchmark sets. Using imaginary frequency integration rather than diagonalization to compute the matrix square root necessary for RPA, evaluation of the RPA correlation energy requires O(N4 log N) operations and O(N3) storage only; the price for this dramatic improvement over existing algorithms is a numerical quadrature. We propose a numerical integration scheme that is exact in the two-orbital case and converges exponentially with the number of grid points. For most systems, 30-40 grid points yield μH accuracy in triple zeta basis sets, but much larger grids are necessary for small gap systems. The lowest-order approximation to the present method is a post-Kohn-Sham frequency-domain version of opposite-spin Laplace-transform RI-MP2 [J. Jung et al., Phys. Rev. B 70, 205107 (2004)]. Timings for polyacenes with up to 30 atoms show speed-ups of two orders of magnitude over previous implementations. The present approach makes it possible to routinely compute RPA correlation energies of systems well beyond 100 atoms, as is demonstrated for the octapeptide angiotensin II.

  1. Bladder transitional cell carcinoma: correlation of contrast enhancement on computed tomography with histological grade and tumour angiogenesis

    International Nuclear Information System (INIS)

    Xie, Q.; Zhang, J.; Wu, P.-H.; Jiang, X.-Q.; Chen, S.-L.; Wang, Q.-L.; Xu, J.; Chen, G.-D.; Deng, J.-H.

    2005-01-01

    AIM: To investigate the correlation between the degree of contrast enhancement of bladder cancer in the early enhanced phase of helical computed tomography (CT) and microvessel density (MVD), vascular endothelial growth factor (VEGF) and histological grade. MATERIALS AND METHODS: Sixty-five patients with transitional cell carcinoma of the bladder were examined by incremental unenhanced CT and helical CT at 40-45 s after initiation of intravenous administration of contrast medium before surgery. The CT density in Hounsfield units of bladder carcinomas were measured in the middle of the maximum diameter section of the cancer lesions on unenhanced and enhanced CT. The degree of contrast enhancement of the tumour was determined as the absolute increase in Hounsfield units. Histological grade, VEGF and MVD were analysed for each cancer. The Pearson and Spearman correlation tests were used to determine the strength of the relationships between CT enhancement and histological grade, VEGF expression and MVD. RESULTS: Different degrees of enhancement were observed in 91 cancers during the early enhanced phase of helical CT. Mean MVDs and mean CT enhancing values of different histological grade groups were statistically different (p<0.001). A positive correlation was found in the CT-enhancing value of bladder cancer and MVD (Pearson correlation test; r=0.938, p<0.001) and histological grade (Spearman rank correlation; r=0.734, p<0.001). VEGF of bladder cancer did not correlate with the change in CT attenuation (Spearman rank correlation; r=0.087, p=0.410) and MVD (Spearman rank correlation, r=0.103, p=0.330). CONCLUSION: In bladder cancer, the degree of contrast enhancement during the early enhanced helical CT is correlated with the MVD and histological grade of tumour. It is possible that MVD is the histopathological basis of early contrast enhancement of bladder cancer

  2. Combination of inquiry learning model and computer simulation to improve mastery concept and the correlation with critical thinking skills (CTS)

    Science.gov (United States)

    Nugraha, Muhamad Gina; Kaniawati, Ida; Rusdiana, Dadi; Kirana, Kartika Hajar

    2016-02-01

    Among the purposes of physics learning at high school is to master the physics concepts and cultivate scientific attitude (including critical attitude), develop inductive and deductive reasoning skills. According to Ennis et al., inductive and deductive reasoning skills are part of critical thinking. Based on preliminary studies, both of the competence are lack achieved, it is seen from student learning outcomes is low and learning processes that are not conducive to cultivate critical thinking (teacher-centered learning). One of learning model that predicted can increase mastery concepts and train CTS is inquiry learning model aided computer simulations. In this model, students were given the opportunity to be actively involved in the experiment and also get a good explanation with the computer simulations. From research with randomized control group pretest-posttest design, we found that the inquiry learning model aided computer simulations can significantly improve students' mastery concepts than the conventional (teacher-centered) method. With inquiry learning model aided computer simulations, 20% of students have high CTS, 63.3% were medium and 16.7% were low. CTS greatly contribute to the students' mastery concept with a correlation coefficient of 0.697 and quite contribute to the enhancement mastery concept with a correlation coefficient of 0.603.

  3. Pneumocystis carinii pneumonia in acquired immunodeficiency syndrome - correlation of high-resolution computed tomography and anatomopathology

    International Nuclear Information System (INIS)

    Marchiori, Edson; Moreira, Luiza Beatriz; Capone, Domenico; Moraes, Heleno Pinto de; Pereira, Cyntia Inez Guedes Soares

    2001-01-01

    We present the main findings observed on the high-resolution computed tomography examinations of 15 patients with acquired immunodeficiency syndrome and Pneumocystis carinii pneumonia. The high-resolution computed tomography and autopsy findings of 5 patients were also compared. The most frequently observed high-resolution computed tomography patterns were ground-glass attenuation, consolidation areas, crazy-paving pattern and cysts. Nodules and intralobular reticulation were less frequently observed. Ground-glass attenuation and consolidation areas corresponded to alveolar filling with inflammatory exudate. Thickening of the interlobular septa was due to cell infiltration and edema. One patient presented interlobular reticulation, and the pathology study revealed alveolar septa thickening due to cell infiltration and fibrosis. Nodules observed in one of the patients corresponded to a patchy intra alveolar accumulation of microorganisms and inflammatory cells forming a 'granulomatous' pattern. (author)

  4. When can Empirical Green Functions be computed from Noise Cross-Correlations? Hints from different Geographical and Tectonic environments

    Science.gov (United States)

    Matos, Catarina; Silveira, Graça; Custódio, Susana; Domingues, Ana; Dias, Nuno; Fonseca, João F. B.; Matias, Luís; Krueger, Frank; Carrilho, Fernando

    2014-05-01

    Noise cross-correlations are now widely used to extract Green functions between station pairs. But, do all the cross-correlations routinely computed produce successful Green Functions? What is the relationship between noise recorded in a couple of stations and the cross-correlation between them? During the last decade, we have been involved in the deployment of several temporary dense broadband (BB) networks within the scope of both national projects and international collaborations. From 2000 to 2002, a pool of 8 BB stations continuously operated in the Azores in the scope of the Memorandum of Understanding COSEA (COordinated Seismic Experiment in the Azores). Thanks to the Project WILAS (West Iberia Lithosphere and Astenosphere Structure, PTDC/CTE-GIX/097946/2008) we temporarily increased the number of BB deployed in mainland Portugal to more than 50 (permanent + temporary) during the period 2010 - 2012. In 2011/12 a temporary pool of 12 seismometers continuously recorded BB data in the Madeira archipelago, as part of the DOCTAR (Deep Ocean Test Array Experiment) project. Project CV-PLUME (Investigation on the geometry and deep signature of the Cape Verde mantle plume, PTDC/CTE-GIN/64330/2006) covered the archipelago of Cape Verde, North Atlantic, with 40 temporary BB stations in 2007/08. Project MOZART (Mozambique African Rift Tomography, PTDC/CTE-GIX/103249/2008), covered Mozambique, East Africa, with 30 temporary BB stations in the period 2011 - 2013. These networks, located in very distinct geographical and tectonic environments, offer an interesting opportunity to study seasonal and spatial variations of noise sources and their impact on Empirical Green functions computed from noise cross-correlation. Seismic noise recorded at different seismic stations is evaluated by computation of the probability density functions of power spectral density (PSD) of continuous data. To assess seasonal variations of ambient noise sources in frequency content, time-series of

  5. The Correlation Between Q-angle (Clinical and TTTGdistance (Axial Computed thomography in Firuzgar Hospital, 2008

    Directory of Open Access Journals (Sweden)

    Ali Yeganeh

    2010-02-01

    Full Text Available Background:The purpose of this study was to evaluate the significance of the Q angle with respect to the patella position. We assess the correlation between the Q angles(calculated by clinical exam in different positions and CT indices (with more impression on TTTG.Method: Atotal number of 68 knee joints of 50 cases entered the study. Clinical examination was used to measure Q angle (in 3 positions of sitting, standing and supine. CT scan performed in 2 axial view of proximal tibia, and distal femor for   measurement of Tibial tuberosity-trochlear groove distance (TTTG and other CT   indices. Correlation between main variables calculated.and analysed with spss.Results: Supine Q angle were strongly correlated with standing Q angles and moderately with sitting Q angle.Sitting Q angle was moderately correlated with supine and standing Q angle and weakly with PTA.we found no other significant correlation between Q angle and CT indexes.Discussion: Our findings suggest that Q angle is not a valuable index for predicting the presence of patelofemoral malalignment.  

  6. Correlates of Strengthening Lessons from HIV/AIDS Treatment and Care Services in Ethiopia Perceived Access and Implications for Health System.

    Directory of Open Access Journals (Sweden)

    Bereket Yakob

    care, health system responsiveness, perceived financial fairness, transportation convenience and satisfaction with services were correlates of perceived access and affected healthcare performance. Interventions targeted at improving access to HIV/AIDS treatment and care services should address these factors. Further studies may be needed to confirm the findings.

  7. Correlation between Computer and Mathematical Literacy Levels of 6th Grade Students

    Science.gov (United States)

    Ic, Unal; Tutak, Tayfun

    2018-01-01

    Literacy has been defined in the literature frequently. Each new interpretation leads to the idea that the definition can change based on the relevant environment, instruments used and/or the intended objective and there might be different types of literacy including computer literacy, media literacy and visual literacy (Reinking, McKenna, Labbo…

  8. Monte Carlo computation of correlation times of independent relaxation modes at criticality

    NARCIS (Netherlands)

    Bloete, H.W.J.; Nightingale, M.P.

    2000-01-01

    We investigate aspects of universality of Glauber critical dynamics in two dimensions. We compute the critical exponent $z$ and numerically corroborate its universality for three different models in the static Ising universality class and for five independent relaxation modes. We also present

  9. A Computer Aided System for Correlation and Prediction of Phase Equilibrium Data

    DEFF Research Database (Denmark)

    Nielsen, T.L.; Gani, Rafiqul

    2001-01-01

    based on mathematical programming. This paper describes the development of a computer aided system for the systematic derivation of appropriate property models to be used in the service role for a specified problem. As a first step, a library of well-known property models ha's been developed...

  10. Information-Processing Correlates of Computer-Assisted Word Learning by Mentally Retarded Students.

    Science.gov (United States)

    Conners, Frances A.; Detterman, Douglas K.

    1987-01-01

    Nineteen moderately/severely retarded students (ages 9-22) completed ten 15-minute computer-assisted instruction sessions and seven basic cognitive tasks measuring simple learning, choice reaction time, relearning, probed recall, stimulus discrimination, tachictoscopic threshold, and recognition memory. Stimulus discrimination, probed recall, and…

  11. Morphological measurements in computed tomography correlate with airflow obstruction in chronic obstructive pulmonary disease: systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Xie, XueQian; Oudkerk, Matthijs; Vliegenthart, Rozemarijn; Jong, Pim A. de; Wang, Ying; Hacken, Nick H.T. ten; Miao, Jingtao; Zhang, GuiXiang; Bock, Geertruida H. de

    2012-01-01

    To determine the correlation between CT measurements of emphysema or peripheral airways and airflow obstruction in chronic obstructive pulmonary disease (COPD). PubMed, Embase and Web of Knowledge were searched from 1976 to 2011. Two reviewers independently screened 1,763 citations to identify articles that correlated CT measurements to airflow obstruction parameters of the pulmonary function test in COPD patients, rated study quality and extracted information. Three CT measurements were accessed: lung attenuation area percentage 1 %pred) and FEV 1 divided by the forced volume vital capacity. Seventy-nine articles (9,559 participants) were included in the systematic review, demonstrating different methodologies, measurements and CT airflow obstruction correlations. There were 15 high-quality articles (2,095 participants) in the meta-analysis. The absolute pooled correlation coefficients ranged from 0.48 (95 % CI, 0.40 to 0.54) to 0.65 (0.58 to 0.71) for inspiratory CT and 0.64 (0.53 to 0.72) to 0.73 (0.63 to 0.80) for expiratory CT. CT measurements of emphysema or peripheral airways are significantly related to airflow obstruction in COPD patients. CT provides a morphological method to investigate airway obstruction in COPD. (orig.)

  12. Computed tomography (CT) findings in 88 neurofibromatosis 1 (NF1) patients: Prevalence rates and correlations of thoracic findings

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Ken, E-mail: k-ueda@radiol.med.osaka-u.ac.jp [Department of Radiology, Osaka University Graduate School of Medicine (Japan); Honda, Osamu [Department of Radiology, Osaka University Graduate School of Medicine (Japan); Satoh, Yukihisa [Department of Diagnostic Radiology, Osaka Medical Center for Cancer and Cardiovascular Diseases (Japan); Kawai, Misa; Gyobu, Tomoko; Kanazawa, Toru; Hidaka, Shojiro; Yanagawa, Masahiro [Department of Radiology, Osaka University Graduate School of Medicine (Japan); Sumikawa, Hiromitsu [Department of Diagnostic Radiology, Osaka Rosai Hospital (Japan); Tomiyama, Noriyuki [Department of Radiology, Osaka University Graduate School of Medicine (Japan)

    2015-06-15

    Highlights: • Various thoracic CT findings, including cysts, mediastinal masses, etc. were found. • Cysts show upper and peripheral dominant distribution. • The number, size, and distribution of the pulmonary cysts in NF-1 revealed significant correlation. • It is suspected that thoracic CT findings in NF-1 occur independently. - Abstract: Purpose: To evaluate the prevalence rates and the correlations of thoracic computed tomography (CT) findings of neurofibromatosis 1 (NF1) in 88 patients. Materials and methods: Chest CT images of 88 NF1 patients were independently reviewed by three observers, and the CT findings were evaluated. If abnormal findings were present, their number, size, and distribution were recorded. The prevalence rate of each CT finding was calculated, and the correlations between CT findings were analyzed. Results: Of the 88 cases, 13 were positive for cysts, 16 for emphysema, 8 for nodules, 8 for GGNs (ground glass nodules), 13 for mediastinal masses, 20 for scoliosis, 44 for subcutaneous nodules, and 34 for skin nodules. Cysts showed upper and peripheral dominant distributions. Regarding 13 mediastinal masses, 2 were diagnosed as malignant peripheral nerve sheath tumors (MPNSTs), 1 was diagnosed as primary lung cancer, 2 were diagnosed as lateral meningocele, 3 were diagnosed as neurofibromas, and the remaining 7 were considered neurofibromas. There was a significant correlation between the prevalence of subcutaneous nodules and that of skin nodules. Significant positive correlations were also seen between size and number, size and rate of central distribution, and number and rate of central distribution of cysts. Conclusion: Various CT findings were found in NF-1 patients, and the prevalence rates of subcutaneous and skin nodules were higher than other findings. Though the prevalence rates of subcutaneous nodules and skin nodules were significantly correlated, the other CT findings in NF-1 occurred independently. The number, size, and

  13. Computed tomography (CT) findings in 88 neurofibromatosis 1 (NF1) patients: Prevalence rates and correlations of thoracic findings

    International Nuclear Information System (INIS)

    Ueda, Ken; Honda, Osamu; Satoh, Yukihisa; Kawai, Misa; Gyobu, Tomoko; Kanazawa, Toru; Hidaka, Shojiro; Yanagawa, Masahiro; Sumikawa, Hiromitsu; Tomiyama, Noriyuki

    2015-01-01

    Highlights: • Various thoracic CT findings, including cysts, mediastinal masses, etc. were found. • Cysts show upper and peripheral dominant distribution. • The number, size, and distribution of the pulmonary cysts in NF-1 revealed significant correlation. • It is suspected that thoracic CT findings in NF-1 occur independently. - Abstract: Purpose: To evaluate the prevalence rates and the correlations of thoracic computed tomography (CT) findings of neurofibromatosis 1 (NF1) in 88 patients. Materials and methods: Chest CT images of 88 NF1 patients were independently reviewed by three observers, and the CT findings were evaluated. If abnormal findings were present, their number, size, and distribution were recorded. The prevalence rate of each CT finding was calculated, and the correlations between CT findings were analyzed. Results: Of the 88 cases, 13 were positive for cysts, 16 for emphysema, 8 for nodules, 8 for GGNs (ground glass nodules), 13 for mediastinal masses, 20 for scoliosis, 44 for subcutaneous nodules, and 34 for skin nodules. Cysts showed upper and peripheral dominant distributions. Regarding 13 mediastinal masses, 2 were diagnosed as malignant peripheral nerve sheath tumors (MPNSTs), 1 was diagnosed as primary lung cancer, 2 were diagnosed as lateral meningocele, 3 were diagnosed as neurofibromas, and the remaining 7 were considered neurofibromas. There was a significant correlation between the prevalence of subcutaneous nodules and that of skin nodules. Significant positive correlations were also seen between size and number, size and rate of central distribution, and number and rate of central distribution of cysts. Conclusion: Various CT findings were found in NF-1 patients, and the prevalence rates of subcutaneous and skin nodules were higher than other findings. Though the prevalence rates of subcutaneous nodules and skin nodules were significantly correlated, the other CT findings in NF-1 occurred independently. The number, size, and

  14. Correlation of primary middle and distal esophageal cancers motion with surrounding tissues using four-dimensional computed tomography.

    Science.gov (United States)

    Wang, Wei; Li, Jianbin; Zhang, Yingjie; Shao, Qian; Xu, Min; Guo, Bing; Shang, Dongping

    2016-01-01

    To investigate the correlation of gross tumor volume (GTV) motion with the structure of interest (SOI) motion and volume variation for middle and distal esophageal cancers using four-dimensional computed tomography (4DCT). Thirty-three patients with middle or distal esophageal carcinoma underwent 4DCT simulation scan during free breathing. All image sets were registered with 0% phase, and the GTV, apex of diaphragm, lung, and heart were delineated on each phase of the 4DCT data. The position of GTV and SOI was identified in all 4DCT phases, and the volume of lung and heart was also achieved. The phase relationship between the GTV and SOI was estimated through Pearson's correlation test. The mean peak-to-peak displacement of all primary tumors in the lateral (LR), anteroposterior (AP), and superoinferior (SI) directions was 0.13 cm, 0.20 cm, and 0.30 cm, respectively. The SI peak-to-peak motion of the GTV was defined as the greatest magnitude of motion. The displacement of GTV correlated well with heart in three dimensions and significantly associated with bilateral lung in LR and SI directions. A significant correlation was found between the GTV and apex of the diaphragm in SI direction (r left=0.918 and r right=0.928). A significant inverse correlation was found between GTV motion and varying lung volume, but the correlation was not significant with heart (r LR=-0.530, r AP=-0.531, and r SI=-0.588) during respiratory cycle. For middle and distal esophageal cancers, GTV should expand asymmetric internal margins. The primary tumor motion has quite good correlation with diaphragm, heart, and lung.

  15. Daily Megavoltage Computed Tomography in Lung Cancer Radiotherapy: Correlation Between Volumetric Changes and Local Outcome

    International Nuclear Information System (INIS)

    Bral, Samuel; De Ridder, Mark; Duchateau, Michael; Gevaert, Thierry; Engels, Benedikt; Schallier, Denis; Storme, Guy

    2011-01-01

    Purpose: To assess the predictive or comparative value of volumetric changes, measured on daily megavoltage computed tomography during radiotherapy for lung cancer. Patients and Methods: We included 80 patients with locally advanced non-small-cell lung cancer treated with image-guided intensity-modulated radiotherapy. The radiotherapy was combined with concurrent chemotherapy, combined with induction chemotherapy, or given as primary treatment. Patients entered two parallel studies with moderately hypofractionated radiotherapy. Tumor volume contouring was done on the daily acquired images. A regression coefficient was derived from the volumetric changes on megavoltage computed tomography, and its predictive value was validated. Logarithmic or polynomial fits were applied to the intratreatment changes to compare the different treatment schedules radiobiologically. Results: Regardless of the treatment type, a high regression coefficient during radiotherapy predicted for a significantly prolonged cause-specific local progression free-survival (p = 0.05). Significant differences were found in the response during radiotherapy. The significant difference in volumetric treatment response between radiotherapy with concurrent chemotherapy and radiotherapy plus induction chemotherapy translated to a superior long-term local progression-free survival for concurrent chemotherapy (p = 0.03). An enhancement ratio of 1.3 was measured for the used platinum/taxane doublet in comparison with radiotherapy alone. Conclusion: Contouring on daily megavoltage computed tomography images during radiotherapy enabled us to predict the efficacy of a given treatment. The significant differences in volumetric response between treatment strategies makes it a possible tool for future schedule comparison.

  16. Correlation of computed tomography, magnetic resonance imaging and clinical outcome in acute carbon monoxide poisoning.

    Science.gov (United States)

    Ozcan, Namik; Ozcam, Giray; Kosar, Pinar; Ozcan, Ayse; Basar, Hulya; Kaymak, Cetin

    2016-01-01

    Carbon monoxide is a toxic gas for humans and is still a silent killer in both developed and developing countries. The aim of this case series was to evaluate early radiological images as a predictor of subsequent neuropsychological sequelae, following carbon monoxide poisoning. After carbon monoxide exposure, early computed tomography scans and magnetic resonance imaging findings of a 52-year-old woman showed bilateral lesions in the globus pallidus. This patient was discharged and followed for 90 days. The patient recovered without any neurological sequela. In a 58-year-old woman exposed to carbon monoxide, computed tomography showed lesions in bilateral globus pallidus and periventricular white matter. Early magnetic resonance imaging revealed changes similar to that like in early tomography images. The patient recovered and was discharged from hospital. On the 27th day of exposure, the patient developed disorientation and memory impairment. Late magnetic resonance imaging showed diffuse hyperintensity in the cerebral white matter. White matter lesions which progress to demyelination and end up in neuropsychological sequelae cannot always be diagnosed by early computed tomography and magnetic resonance imaging in carbon monoxide poisoning. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  17. A Novel Multilayer Correlation Maximization Model for Improving CCA-Based Frequency Recognition in SSVEP Brain-Computer Interface.

    Science.gov (United States)

    Jiao, Yong; Zhang, Yu; Wang, Yu; Wang, Bei; Jin, Jing; Wang, Xingyu

    2018-05-01

    Multiset canonical correlation analysis (MsetCCA) has been successfully applied to optimize the reference signals by extracting common features from multiple sets of electroencephalogram (EEG) for steady-state visual evoked potential (SSVEP) recognition in brain-computer interface application. To avoid extracting the possible noise components as common features, this study proposes a sophisticated extension of MsetCCA, called multilayer correlation maximization (MCM) model for further improving SSVEP recognition accuracy. MCM combines advantages of both CCA and MsetCCA by carrying out three layers of correlation maximization processes. The first layer is to extract the stimulus frequency-related information in using CCA between EEG samples and sine-cosine reference signals. The second layer is to learn reference signals by extracting the common features with MsetCCA. The third layer is to re-optimize the reference signals set in using CCA with sine-cosine reference signals again. Experimental study is implemented to validate effectiveness of the proposed MCM model in comparison with the standard CCA and MsetCCA algorithms. Superior performance of MCM demonstrates its promising potential for the development of an improved SSVEP-based brain-computer interface.

  18. POLYMAT-C: a comprehensive SPSS program for computing the polychoric correlation matrix.

    Science.gov (United States)

    Lorenzo-Seva, Urbano; Ferrando, Pere J

    2015-09-01

    We provide a free noncommercial SPSS program that implements procedures for (a) obtaining the polychoric correlation matrix between a set of ordered categorical measures, so that it can be used as input for the SPSS factor analysis (FA) program; (b) testing the null hypothesis of zero population correlation for each element of the matrix by using appropriate simulation procedures; (c) obtaining valid and accurate confidence intervals via bootstrap resampling for those correlations found to be significant; and (d) performing, if necessary, a smoothing procedure that makes the matrix amenable to any FA estimation procedure. For the main purpose (a), the program uses a robust unified procedure that allows four different types of estimates to be obtained at the user's choice. Overall, we hope the program will be a very useful tool for the applied researcher, not only because it provides an appropriate input matrix for FA, but also because it allows the researcher to carefully check the appropriateness of the matrix for this purpose. The SPSS syntax, a short manual, and data files related to this article are available as Supplemental materials that are available for download with this article.

  19. Correlation of uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT)and treatment response in patients with knee pain

    International Nuclear Information System (INIS)

    Koh, Geon; Hwang, Kyung Hoon; Lee, Hae Jin; Kim, Seog Gyun; Lee, Beom Koo

    2016-01-01

    To determine whether treatment response in patients with knee pain could be predicted using uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT) images. Ninety-five patients with knee pain who had undergone SPECT/CT were included in this retrospective study. Subjects were divided into three groups: increased focal uptake (FTU), increased irregular tracer uptake (ITU), and no tracer uptake (NTU). A numeric rating scale (NRS-11) assessed pain intensity. We analyzed the association between uptake patterns and treatment response using Pearson's chi-square test and Fisher's exact test. Uptake was quantified from SPECT/CT with region of interest (ROI) counting, and an intraclass correlation coefficient (ICC) calculated agreement. We used Student' t-test to calculate statistically significant differences of counts between groups and the Pearson correlation to measure the relationship between counts and initial NRS-1k1. Multivariate logistic regression analysis determined which variables were significantly associated with uptake. The FTU group included 32 patients; ITU, 39; and NTU, 24. With conservative management, 64 % of patients with increased tracer uptake (TU, both focal and irregular) and 36 % with NTU showed positive response. Conservative treatment response of FTU was better than NTU, but did not differ from that of ITU. Conservative treatment response of TU was significantly different from that of NTU (OR 3.1; p 0.036). Moderate positive correlation was observed between ITU and initial NRS-11. Age and initial NRS-11 significantly predicted uptake. Patients with uptake in their knee(s) on SPECT/CT showed positive treatment response under conservative treatment

  20. Correlation of uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT)and treatment response in patients with knee pain

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Geon; Hwang, Kyung Hoon; Lee, Hae Jin; Kim, Seog Gyun; Lee, Beom Koo [Gachon University Gil Hospital, Incheon (Korea, Republic of)

    2016-06-15

    To determine whether treatment response in patients with knee pain could be predicted using uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT) images. Ninety-five patients with knee pain who had undergone SPECT/CT were included in this retrospective study. Subjects were divided into three groups: increased focal uptake (FTU), increased irregular tracer uptake (ITU), and no tracer uptake (NTU). A numeric rating scale (NRS-11) assessed pain intensity. We analyzed the association between uptake patterns and treatment response using Pearson's chi-square test and Fisher's exact test. Uptake was quantified from SPECT/CT with region of interest (ROI) counting, and an intraclass correlation coefficient (ICC) calculated agreement. We used Student' t-test to calculate statistically significant differences of counts between groups and the Pearson correlation to measure the relationship between counts and initial NRS-1k1. Multivariate logistic regression analysis determined which variables were significantly associated with uptake. The FTU group included 32 patients; ITU, 39; and NTU, 24. With conservative management, 64 % of patients with increased tracer uptake (TU, both focal and irregular) and 36 % with NTU showed positive response. Conservative treatment response of FTU was better than NTU, but did not differ from that of ITU. Conservative treatment response of TU was significantly different from that of NTU (OR 3.1; p 0.036). Moderate positive correlation was observed between ITU and initial NRS-11. Age and initial NRS-11 significantly predicted uptake. Patients with uptake in their knee(s) on SPECT/CT showed positive treatment response under conservative treatment.

  1. Real-time optical correlator using computer-generated holographic filter on a liquid crystal light valve

    Science.gov (United States)

    Chao, Tien-Hsin; Yu, Jeffrey

    1990-01-01

    Limitations associated with the binary phase-only filter often used in optical correlators are presently circumvented in the writing of complex-valued data on a gray-scale spatial light modulator through the use of a computer-generated hologram (CGH) algorithm. The CGH encodes complex-valued data into nonnegative real CGH data in such a way that it may be encoded in any of the available gray-scale spatial light modulators. A CdS liquid-crystal light valve is used for the complex-valued CGH encoding; computer simulations and experimental results are compared, and the use of such a CGH filter as the synapse hologram in a holographic optical neural net is discussed.

  2. Correlation signatures of wet soils and snows. [algorithm development and computer programming

    Science.gov (United States)

    Phillips, M. R.

    1972-01-01

    Interpretation, analysis, and development of algorithms have provided the necessary computational programming tools for soil data processing, data handling and analysis. Algorithms that have been developed thus far, are adequate and have been proven successful for several preliminary and fundamental applications such as software interfacing capabilities, probability distributions, grey level print plotting, contour plotting, isometric data displays, joint probability distributions, boundary mapping, channel registration and ground scene classification. A description of an Earth Resources Flight Data Processor, (ERFDP), which handles and processes earth resources data under a users control is provided.

  3. Spiral computed tomography during arterial portography of the liver: correlations between radiological and intraoperative findings and evaluation of operability

    International Nuclear Information System (INIS)

    Layer, G.; Runge, I.; Conrad, R.; Pauleit, D.; Jaeger, U.; Schild, H.H.; Gallkowski, U.; Wolff, M.; Hirner, A.

    1999-01-01

    Purpose: To evaluate the accuracy of spiral computed tomography during arterial portography (SCTAP) in the detection, localization, and resectablility of liver tumors in a correlative study between radiology and intraoperative findings. Method and Materials: Retrospectively, SCTAP images of 168 consecutive patients before liver tumor resection were analyzed. The SCTAP studies (100 ml Iopromid 300 by automated injector with a flow of 3 ml/s; slice thickness, table feed and reconstruction index 5 mm each; scan-delay 30 s; 120 kV; 250 mAs) were evaluated for the detection, localization, and resectability of focal liver lesions by three experienced radiologists in consensus and were correlated with histopathological and intraoperative findings where available (59/168). Results: The sensitivity of SCTAP for the detection of liver tumors was 91% for all lesions and 84% for lesions [de

  4. 3D CFD computations of transitional flows using DES and a correlation based transition model; Wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Niels N.

    2009-07-15

    The report describes the application of the correlation based transition model of Menter et. al. [1, 2] to the cylinder drag crisis and the stalled flow over an DU-96-W-351 airfoil using the DES methodology. When predicting the flow over airfoils and rotors, the laminar-turbulent transition process can be important for the aerodynamic performance. Today, the most widespread approach is to use fully turbulent computations, where the transitional process is ignored and the entire boundary layer on the wings or airfoils is handled by the turbulence model. The correlation based transition model has lately shown promising results, and the present paper describes the application of the model to predict the drag and shedding frequency for flow around a cylinder from sub to super-critical Reynolds numbers. Additionally, the model is applied to the flow around the DU-96 airfoil, at high angles of attack. (au)

  5. Computed tomography of the dog's brain: normal aspects and anatomical correlation

    International Nuclear Information System (INIS)

    Lorigados, C.A.B.; Pinto, A.C.B.F.

    2013-01-01

    Normal tomographic images of dog's heads were obtained, aimed to familiarize them with the normal aspects of the brain and correlate these findings with the relevant anatomy of the region studied. Several anatomical structures, such as the parenchyma of the frontal, parietal, temporal and occipital lobes, the longitudinal fissure, the ventricular system, the cerebellum, the olfactory bulb, the corpus callosum, diencephalon, the pons, the medulla oblongata and the chiasmatic sulcus were directly identified or were related to neighboring structures which helped in their identification. (author)

  6. Application of Computational Fluid Dynamics (CFD) in transonic wind-tunnel/flight-test correlation

    Science.gov (United States)

    Murman, E. M.

    1982-01-01

    The capability for calculating transonic flows for realistic configurations and conditions is discussed. Various phenomena which were modeled are shown to have the same order of magnitude on the influence of predicted results. It is concluded that CFD can make the following contributions to the task of correlating wind tunnel and flight test data: some effects of geometry differences and aeroelastic distortion can be predicted; tunnel wall effects can be assessed and corrected for; and the effects of model support systems and free stream nonuniformities can be modeled.

  7. Mapping soil deformation around plant roots using in vivo 4D X-ray Computed Tomography and Digital Volume Correlation.

    Science.gov (United States)

    Keyes, S D; Gillard, F; Soper, N; Mavrogordato, M N; Sinclair, I; Roose, T

    2016-06-14

    The mechanical impedance of soils inhibits the growth of plant roots, often being the most significant physical limitation to root system development. Non-invasive imaging techniques have recently been used to investigate the development of root system architecture over time, but the relationship with soil deformation is usually neglected. Correlative mapping approaches parameterised using 2D and 3D image data have recently gained prominence for quantifying physical deformation in composite materials including fibre-reinforced polymers and trabecular bone. Digital Image Correlation (DIC) and Digital Volume Correlation (DVC) are computational techniques which use the inherent material texture of surfaces and volumes, captured using imaging techniques, to map full-field deformation components in samples during physical loading. Here we develop an experimental assay and methodology for four-dimensional, in vivo X-ray Computed Tomography (XCT) and apply a Digital Volume Correlation (DVC) approach to the data to quantify deformation. The method is validated for a field-derived soil under conditions of uniaxial compression, and a calibration study is used to quantify thresholds of displacement and strain measurement. The validated and calibrated approach is then demonstrated for an in vivo test case in which an extending maize root in field-derived soil was imaged hourly using XCT over a growth period of 19h. This allowed full-field soil deformation data and 3D root tip dynamics to be quantified in parallel for the first time. This fusion of methods paves the way for comparative studies of contrasting soils and plant genotypes, improving our understanding of the fundamental mechanical processes which influence root system development. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Cops, Computers and the Right to Privacy in the Information Age: unauthorised access and inapropriate disclosure of information complaints in New South Wales

    Directory of Open Access Journals (Sweden)

    Mike Enders

    2001-05-01

    Full Text Available The term the 'information age' is particularly applicable to Australia. In a recent email, the Australian Institute of Criminology's Chief Librarian, John Myrtle, passed on statistics which showed that internet use and access in Australia has increased about 50% during the last year (Pers. Comm. 14 July 1999. Of greater interest is the fact that almost 20% of Australian households, 1.3 million, have internet access and over one third of the adult population has accessed the internet at some time during the year ending February 1999. To further back these figures, the Sydney Morning Herald of 12 February, 2000, carried statistics from the Australian Bureau of Statistics which showed that 22.6% of Australian families had home internet access (Anon., 2000a, p. 105. These figures firmly place Australians among the world's most computer literate societies. Of course computers weren't always that popular. The authors of this paper entered law enforcement at a time when computers were owned by Universities and major corporations - not individuals - and a decent calculator cost about a week's wages. However, things changed quickly and by the 1980s computers were an established part of policing. Today, all major police services are committed to, and reliant on, some form of computerised information system. The two systems which the authors have had contact with are the Crime Reporting and Information System for Police (CRISP (Queensland Police Service and the Computerised Operational Policing System (COPS (New South Wales Police Service. While many aspects of these two systems are different, they, and all the other police information systems in existence, share one major similarity: they store and provide access to personal and confidential information on every individual with whom police come into contact during their duties. Modern police investigation techniques rely on officers being able to access this information routinely to carry out their duties

  9. Ultrasound appearance of radiation-induced hepatic injury. Correlation with computed tomography and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Garra, B.S.; Shawker, T.H.; Chang, R.; Kaplan, K.; White, R.D.

    1988-01-01

    The ultrasound findings in three cases of radiation-induced hepatic injury are described and compared with computed tomography and magnetic resonance imaging findings. Fatty infiltration of the liver was present in two of the cases in which concurrent chemotherapy was being administered. On ultrasound B-scans, the regions of radiation injury were hypoechoic relative to the remainder of the liver. This finding was more obvious in the patients with fatty livers. CT scans on the patients with fatty infiltrated livers showed higher attenuation in the irradiated region than in unexposed liver. In the patient where no fatty infiltration was present, the radiated section of liver had lower attenuation consistent with previous reports. Magnetic resonance imaging showed decreased signal in the exposed areas on T1 weighted images

  10. Neural correlates of learning in an electrocorticographic motor-imagery brain-computer interface

    Science.gov (United States)

    Blakely, Tim M.; Miller, Kai J.; Rao, Rajesh P. N.; Ojemann, Jeffrey G.

    2014-01-01

    Human subjects can learn to control a one-dimensional electrocorticographic (ECoG) brain-computer interface (BCI) using modulation of primary motor (M1) high-gamma activity (signal power in the 75–200 Hz range). However, the stability and dynamics of the signals over the course of new BCI skill acquisition have not been investigated. In this study, we report 3 characteristic periods in evolution of the high-gamma control signal during BCI training: initial, low task accuracy with corresponding low power modulation in the gamma spectrum, followed by a second period of improved task accuracy with increasing average power separation between activity and rest, and a final period of high task accuracy with stable (or decreasing) power separation and decreasing trial-to-trial variance. These findings may have implications in the design and implementation of BCI control algorithms. PMID:25599079

  11. Premonitory urges and tics in Tourette syndrome: computational mechanisms and neural correlates.

    Science.gov (United States)

    Conceição, Vasco A; Dias, Ângelo; Farinha, Ana C; Maia, Tiago V

    2017-10-01

    Tourette syndrome is characterized by open motor behaviors - tics - but another crucial aspect of the disorder is the presence of premonitory urges: uncomfortable sensations that typically precede tics and are temporarily alleviated by tics. We review the evidence implicating the somatosensory cortices and the insula in premonitory urges and the motor cortico-basal ganglia-thalamo-cortical loop in tics. We consider how these regions interact during tic execution, suggesting that the insula plays an important role as a nexus linking the sensory and emotional character of premonitory urges with their translation into tics. We also consider how these regions interact during tic learning, integrating the neural evidence with a computational perspective on how premonitory-urge alleviation reinforces tics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A postmortem correlation of computer tomography and ultrasound scans of periventricular hemorrhage in preterm infants

    International Nuclear Information System (INIS)

    Fukuda, Seiichi; Hashimoto, Takeo; Yamashita, Yushiro; Nishimi, Toshihiro; Utsunomiya, Hidetsuna; Nakamura, Yasuhiro; Okudera, Toshio

    1988-01-01

    From January 1984 through September 1987, ultrasound scanning (US), computed tomography (CT), and autopy have been performed in 80 consecutive premature infants. Intracranial lesions consisted of intraventricular hemorrhage (IVH, n = 61), subarachnoid hemorrhage (SAH, n = 63), cerebellar hemorrhage (n = 5), hydrocephalus (n = 8), periventricular leukoencephalomalacia (n = 20), and anoxic encephalopathy (n = 40). Using autopsy findings as the standard, both US and CT had an accuracy of 80 % or more in detecting subependymal hemorrhage (SEH), IVH, dilated ventricle, and parenchymal hemorrhage ; however, both imaging modalities showed a high false negative for SAH (77 % for US vs 55 % for CT). Accuracy of US and CT was 82 % vs 72 % for SEH, and 72 % vs 85 % for IVH. High false positive and false negative rates, in spite of 80 % or more accuracy of imaging modalities, warrant further studies to obtain higher accuracy in the diagnosis of intracranial lesions. (Namekawa, K.)

  13. Postmortem correlation of computer tomography and ultrasound scans of periventricular hemorrhage in preterm infants

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Seiichi; Hashimoto, Takeo; Yamashita, Yushiro; Nishimi, Toshihiro; Utsunomiya, Hidetsuna; Nakamura, Yasuhiro; Okudera, Toshio

    1988-08-01

    From January 1984 through September 1987, ultrasound scanning (US), computed tomography (CT), and autopy have been performed in 80 consecutive premature infants. Intracranial lesions consisted of intraventricular hemorrhage (IVH, n = 61), subarachnoid hemorrhage (SAH, n = 63), cerebellar hemorrhage (n = 5), hydrocephalus (n = 8), periventricular leukoencephalomalacia (n = 20), and anoxic encephalopathy (n = 40). Using autopsy findings as the standard, both US and CT had an accuracy of 80 % or more in detecting subependymal hemorrhage (SEH), IVH, dilated ventricle, and parenchymal hemorrhage ; however, both imaging modalities showed a high false negative for SAH (77 % for US vs 55 % for CT). Accuracy of US and CT was 82 % vs 72 % for SEH, and 72 % vs 85 % for IVH. High false positive and false negative rates, in spite of 80 % or more accuracy of imaging modalities, warrant further studies to obtain higher accuracy in the diagnosis of intracranial lesions. (Namekawa, K.).

  14. Building a Unified Computational Model for the Resonant X-Ray Scattering of Strongly Correlated Materials

    Energy Technology Data Exchange (ETDEWEB)

    Bansil, Arun [Northeastern Univ., Boston, MA (United States)

    2016-12-01

    Basic-Energy Sciences of the Department of Energy (BES/DOE) has made large investments in x-ray sources in the U.S. (NSLS-II, LCLS, NGLS, ALS, APS) as powerful enabling tools for opening up unprecedented new opportunities for exploring properties of matter at various length and time scales. The coming online of the pulsed photon source literally allows us to see and follow the dynamics of processes in materials at their natural timescales. There is an urgent need therefore to develop theoretical methodologies and computational models for understanding how x-rays interact with matter and the related spectroscopies of materials. The present project addressed aspects of this grand challenge of X-ray science. In particular, our Collaborative Research Team (CRT) focused on understanding and modeling of elastic and inelastic resonant X-ray scattering processes. We worked to unify the three different computational approaches currently used for modeling X-ray scattering—density functional theory, dynamical mean-field theory, and small-cluster exact diagonalization—to achieve a more realistic material-specific picture of the interaction between X-rays and complex matter. To achieve a convergence in the interpretation and to maximize complementary aspects of different theoretical methods, we concentrated on the cuprates, where most experiments have been performed. Our team included both US and international researchers, and it fostered new collaborations between researchers currently working with different approaches. In addition, we developed close relationships with experimental groups working in the area at various synchrotron facilities in the US. Our CRT thus helped toward enabling the US to assume a leadership role in the theoretical development of the field, and to create a global network and community of scholars dedicated to X-ray scattering research.

  15. Building a Unified Computational Model for the Resonant X-Ray Scattering of Strongly Correlated Materials

    International Nuclear Information System (INIS)

    Bansil, Arun

    2016-01-01

    Basic-Energy Sciences of the Department of Energy (BES/DOE) has made large investments in x-ray sources in the U.S. (NSLS-II, LCLS, NGLS, ALS, APS) as powerful enabling tools for opening up unprecedented new opportunities for exploring properties of matter at various length and time scales. The coming online of the pulsed photon source literally allows us to see and follow the dynamics of processes in materials at their natural timescales. There is an urgent need therefore to develop theoretical methodologies and computational models for understanding how x-rays interact with matter and the related spectroscopies of materials. The present project addressed aspects of this grand challenge of X-ray science. In particular, our Collaborative Research Team (CRT) focused on understanding and modeling of elastic and inelastic resonant X-ray scattering processes. We worked to unify the three different computational approaches currently used for modeling X-ray scattering-density functional theory, dynamical mean-field theory, and small-cluster exact diagonalization-to achieve a more realistic material-specific picture of the interaction between X-rays and complex matter. To achieve a convergence in the interpretation and to maximize complementary aspects of different theoretical methods, we concentrated on the cuprates, where most experiments have been performed. Our team included both US and international researchers, and it fostered new collaborations between researchers currently working with different approaches. In addition, we developed close relationships with experimental groups working in the area at various synchrotron facilities in the US. Our CRT thus helped toward enabling the US to assume a leadership role in the theoretical development of the field, and to create a global network and community of scholars dedicated to X-ray scattering research.

  16. Advanced Gastric Cancer and Perfusion Imaging Using a Multidetector Row Computed Tomography: Correlation with Prognostic Determinants

    International Nuclear Information System (INIS)

    Zhang, Huan; Pan, Zilai; Du, Lianjun; Yan, Chao; Ding, Bei; Song, Qi; Ling, Huawei; Chen, Kemin

    2008-01-01

    Objective : To investigate the relationship between the perfusion CT features and the clinicopathologically determined prognostic factors in advanced gastric cancer cases. Materials and Methods : A perfusion CT was performed on 31 patients with gastric cancer one week before surgery using a 16-channel multi-detector CT (MDCT) instrument. The data were analyzed with commercially available software to calculate tumor blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS). The microvessel density (MVD), was evaluated by immunohistochemical staining of the surgical specimens with anti-CD34. All of the findings were analyzed prospectively and correlated with the clinicopathological findings, which included histological grading, presence of lymph node metastasis, serosal involvement, distant metastasis, tumor, node, metastasis (TNM) staging, and MVD. The statistical analyses used included the Student's t-test and the Spearman rank correlation were performed in SPSS 11.5. Result : The mean perfusion values and MVD for tumors were as follows: BF (48.14+/-16.46 ml/100 g/min), BV (6.70+/-2.95 ml/100 g), MTT (11.75+/-4.02 s), PS (14.17+/-5.23 ml/100 g/min) and MVD (41.7+/-11.53). Moreover, a significant difference in the PS values was found between patients with or without lymphatic involvement (p = 0.038), as well as with different histological grades (p 0.04) and TNM stagings (p = 0.026). However, BF, BV, MTT, and MVD of gastric cancer revealed no significant relationship with the clinicopathological findings described above (p > 0.05). Conclusion : The perfusion CT values of the permeable surface could serve as a useful prognostic indicator in patients with advanced gastric cancer

  17. Advanced Gastric Cancer and Perfusion Imaging Using a Multidetector Row Computed Tomography: Correlation with Prognostic Determinants

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Huan; Pan, Zilai; Du, Lianjun; Yan, Chao; Ding, Bei; Song, Qi; Ling, Huawei; Chen, Kemin [Jiaotong University, Jiaotong (China)

    2008-04-15

    Objective : To investigate the relationship between the perfusion CT features and the clinicopathologically determined prognostic factors in advanced gastric cancer cases. Materials and Methods : A perfusion CT was performed on 31 patients with gastric cancer one week before surgery using a 16-channel multi-detector CT (MDCT) instrument. The data were analyzed with commercially available software to calculate tumor blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS). The microvessel density (MVD), was evaluated by immunohistochemical staining of the surgical specimens with anti-CD34. All of the findings were analyzed prospectively and correlated with the clinicopathological findings, which included histological grading, presence of lymph node metastasis, serosal involvement, distant metastasis, tumor, node, metastasis (TNM) staging, and MVD. The statistical analyses used included the Student's t-test and the Spearman rank correlation were performed in SPSS 11.5. Result : The mean perfusion values and MVD for tumors were as follows: BF (48.14+/-16.46 ml/100 g/min), BV (6.70+/-2.95 ml/100 g), MTT (11.75+/-4.02 s), PS (14.17+/-5.23 ml/100 g/min) and MVD (41.7+/-11.53). Moreover, a significant difference in the PS values was found between patients with or without lymphatic involvement (p = 0.038), as well as with different histological grades (p 0.04) and TNM stagings (p = 0.026). However, BF, BV, MTT, and MVD of gastric cancer revealed no significant relationship with the clinicopathological findings described above (p > 0.05). Conclusion : The perfusion CT values of the permeable surface could serve as a useful prognostic indicator in patients with advanced gastric cancer.

  18. The solvent effects on dimethyl phthalate investigated by FTIR characterization, solvent parameter correlation and DFT computation

    Science.gov (United States)

    Chen, Yi; Zhang, Hui; Zhou, Wenzhao; Deng, Chao; Liao, Jian

    2018-06-01

    This study set out with the aim of investigating the solvent effects on dimethyl phthalate (DMP) using FTIR characterization, solvent parameter correlation and DFT calculation. DMP exposed to 17 organic solvents manifested varying shift in the carbonyl stretching vibration frequency (νCdbnd O). Non-alkanols induced Band I and alkanols produced Band I and Band II. Through correlating the νCdbnd O with the empirical solvent scales including acceptor parameter (AN), Schleyer's linear free energy parameter (G), and linear free salvation energy relationships (LSER), Band I was mainly ascribed to non-specific effects from either non-alkanols or alkanol polymers ((alkanol)n). νCdbnd O of the latter indicated minor red shift and less variability compared to the former. An assumption was made and validated about the sequestering of hydroxyl group by the bulky hydrophobic chain in (alkanol)n, creating what we refer to as "screening effects". Ab initio calculation, on the other hand, provided insights for possible hydrogen binding between DMP and (ethanol)n or between ethanol monomers. The two components of Band I observed in inert solvents were assigned to the two Cdbnd O groups adopting differentiated conformations. This in turn prompted our consideration that hydrogen binding was highly selective in favor of lowly associated (alkanol)n and the particular Cdbnd O group having relatively less steric hindrance and stronger electron-donating capacity. Band II was therefore believed to derive from hydrogen-bond interactions mainly in manner of 1:1 and 1:2 DMP-(alkanol)n complexes.

  19. Correlation of primary middle and distal esophageal cancers motion with surrounding tissues using four-dimensional computed tomography

    Directory of Open Access Journals (Sweden)

    Wang W

    2016-06-01

    Full Text Available Wei Wang,1 Jianbin Li,1 Yingjie Zhang,1 Qian Shao,1 Min Xu,1 Bing Guo,1 Dongping Shang2 1Department of Radiation Oncology, 2Department of Big Bore CT Room, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, Shandong, People’s Republic of China Purpose: To investigate the correlation of gross tumor volume (GTV motion with the structure of interest (SOI motion and volume variation for middle and distal esophageal cancers using four-dimensional computed tomography (4DCT.Patients and methods: Thirty-three patients with middle or distal esophageal carcinoma underwent 4DCT simulation scan during free breathing. All image sets were registered with 0% phase, and the GTV, apex of diaphragm, lung, and heart were delineated on each phase of the 4DCT data. The position of GTV and SOI was identified in all 4DCT phases, and the volume of lung and heart was also achieved. The phase relationship between the GTV and SOI was estimated through Pearson’s correlation test.Results: The mean peak-to-peak displacement of all primary tumors in the lateral (LR, anteroposterior (AP, and superoinferior (SI directions was 0.13 cm, 0.20 cm, and 0.30 cm, respectively. The SI peak-to-peak motion of the GTV was defined as the greatest magnitude of motion. The displacement of GTV correlated well with heart in three dimensions and significantly associated with bilateral lung in LR and SI directions. A significant correlation was found between the GTV and apex of the diaphragm in SI direction (rleft=0.918 and rright=0.928. A significant inverse correlation was found between GTV motion and varying lung volume, but the correlation was not significant with heart (rLR=–0.530, rAP=–0.531, and rSI=–0.588 during respiratory cycle.Conclusion: For middle and distal esophageal cancers, GTV should expand asymmetric internal margins. The primary tumor motion has quite good correlation with diaphragm, heart, and lung. Keywords

  20. Computer aided diagnosis system for Alzheimer disease using brain diffusion tensor imaging features selected by Pearson's correlation.

    Science.gov (United States)

    Graña, M; Termenon, M; Savio, A; Gonzalez-Pinto, A; Echeveste, J; Pérez, J M; Besga, A

    2011-09-20

    The aim of this paper is to obtain discriminant features from two scalar measures of Diffusion Tensor Imaging (DTI) data, Fractional Anisotropy (FA) and Mean Diffusivity (MD), and to train and test classifiers able to discriminate Alzheimer's Disease (AD) patients from controls on the basis of features extracted from the FA or MD volumes. In this study, support vector machine (SVM) classifier was trained and tested on FA and MD data. Feature selection is done computing the Pearson's correlation between FA or MD values at voxel site across subjects and the indicative variable specifying the subject class. Voxel sites with high absolute correlation are selected for feature extraction. Results are obtained over an on-going study in Hospital de Santiago Apostol collecting anatomical T1-weighted MRI volumes and DTI data from healthy control subjects and AD patients. FA features and a linear SVM classifier achieve perfect accuracy, sensitivity and specificity in several cross-validation studies, supporting the usefulness of DTI-derived features as an image-marker for AD and to the feasibility of building Computer Aided Diagnosis systems for AD based on them. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  1. Correlative single photon emission computed tomography imaging of [123I]altropane binding in the rat model of Parkinson's

    International Nuclear Information System (INIS)

    Gleave, Jacqueline A.; Farncombe, Troy H.; Saab, Chantal; Doering, Laurie C.

    2011-01-01

    Introduction: This study used the dopamine transporter (DAT) probe, [ 123 I]-2β-carbomethoxy-3β-(4-fluorophenyl)-N-(3-iodo-E-allyl)nortropane ([ 123 I]altropane), to assess the DAT levels in the 6-hydroxydopamine rat model of Parkinson's disease. We sought to assess if the right to left [ 123 I]altropane striatal ratios correlated with dopamine content in the striatum and substantia nigra and with behavioural outcomes. Methods: [ 123 I]altropane images taken pre- and postlesion were acquired before and after the transplantation of neural stem/progenitor cells. The images obtained using [ 123 I]altropane and single photon emission computed tomography (SPECT) were compared with specific behavioural tests and the dopamine content assessed by high-performance liquid chromatography. Results: [ 123 I]altropane binding correlated with the content of dopamine in the striatum; however, [ 123 I]altropane binding did not correlate with the dopamine content in the substantia nigra. There was a significant correlation of altropane ratios with the cylinder test and the postural instability test, but not with amphetamine rotations. The low coefficient of determination (r 2 ) for these correlations indicated that [ 123 I]altropane SPECT was not a good predictor of behavioural outcomes. Conclusion: Our data reveal that [ 123 I]altropane predicts the integrity of the striatal dopamine nerve terminals, but does not predict the integrity of the nigrostriatal system. [ 123 I]altropane could be a useful marker to measure dopamine content in cell replacement therapies; however, it would not be able to evaluate outcomes for neuroprotective strategies.

  2. Studies on the correlation between photograph condition and image quality on computed radiography

    International Nuclear Information System (INIS)

    Ding Wenhong; Zhang Weimin; Ding Xingfa

    2007-01-01

    Objective: To evaluate how to use reasonably the combination of exposure dose and speed class on the base of imaging quality on computed radiography (CB). Methods: Based on threshold contrast- detail detectability (TCCD)technique, phantom TO. 16 photography was done with 55, 65 and 75 kV, and combination with three kinds of different exposure dose and speed class respectively. Three radiologists scored each image sequence using double blind method and calculated the threshold detection index (H T ). The imaging quality of knee joint, chest and lumbarspine was also evaluated by these radiologists on the base of diagnostic quality and the different combination of exposure close and speed class. Results: Exposure dose was increased by using lower kV value, and Hr value was increased by lower exposure grade rather than higher kV value. Exposure dose was decreased obviously and speed class was increased in the good contrast location at the same kV value. Conclusions: Based on the demand of diagnostic quality and the contrast of the checked location, the speed class should be carefully selected to decrease the radiation dose exposure to patients, without any decrease of the diagnostic quality. (authors)

  3. Radiographic Evaluation of Valvular Heart Disease With Computed Tomography and Magnetic Resonance Correlation.

    Science.gov (United States)

    Lempel, Jason K; Bolen, Michael A; Renapurkar, Rahul D; Azok, Joseph T; White, Charles S

    2016-09-01

    Valvular heart disease is a group of complex entities with varying etiologies and clinical presentations. There are a number of imaging tools available to supplement clinical evaluation of suspected valvular heart disease, with echocardiography being the most common and clinically established, and more recent emergence of computed tomography and magnetic resonance imaging as additional supportive techniques. Yet even with these newer and more sophisticated modalities, chest radiography remains one of the earliest and most common diagnostic examinations performed during the triage of patients with suspected cardiac dysfunction. Recognizing the anatomic and pathologic features of cardiac radiography including the heart's adaptation to varying hemodynamic changes can provide clues to the radiologist regarding the underlying etiology. In this article, we will elucidate several principles relating to chamber modifications in response to pressure and volume overload as well as radiographic appearances associated with pulmonary fluid status and cardiac dysfunction. We will also present a pattern approach to optimize analysis of the chest radiograph for valvular heart disease, which will help guide the radiologist down a differential diagnostic pathway and create a more meaningful clinical report.

  4. Internal carotid arterial occlusion in computed tomography. Correlation of CT and angiographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Harada, K.; Miura, T.; Nishikubo, Y.; Kawai, R.; Mitomo, M. (Osaka Univ. (Japan). Faculty of Medicine)

    1981-09-01

    The computed tomographic appearance of internal carotid arterial occlusion was reviewed in 33 patients. In 23 of them, who underwent 4-vessel study, the angiographic and CT findings were compared. Ten patients were disclosed to have watershed infarction by CT. Seven of them had watershed processes in the centrum semiovale which were considered to be terminal infarction. Patients who showed watershed infarction under CT revealed inadequate circle of Willis and well-developed cortical anastomosis under angiography. Unilaterally accentuated cerebral atrophy, which we have called asymmetrical atrophy in this paper, was noted in 10 patients. The findings of asymmetrical cerebral atrophy sometimes resemble the changes secondary to old infarction. However, the changes in the lateral ventricle caused by asymmetrical cerebral atrophy are somewhat different from those resulting from old infarction. The angiographic findings suggested that asymmetrical cerebral atrophy is, in addition to being associated with incomplete circle of Willis, also associated with local circulatory disturbances which further decrease the regional cerebral blood flow in the affected hemisphere.

  5. Computed tomography findings of hepatic veno-occlusive disease caused by Sedum aizoon with histopathological correlation

    Energy Technology Data Exchange (ETDEWEB)

    Shao, H.; Chen, H. Z., E-mail: chenhz@enzemed.com; Zhu, J. S. [Department of Infectious Diseases, Taizhou Hospital Affiliated to Wenzhou Medical College, Linhai (China); Ruan, B. [State Key Laboratory for Diagnosis and Treatment of Infectious Disease, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou (China); Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou (China); Zhang, Z. Q. [Department of Infectious Disease, Xianju Hospital of Traditional Chinese Medicine, Xianju (China); Lin, X.; Gan, M. F. [Department of Infectious Diseases, Taizhou Hospital Affiliated to Wenzhou Medical College, Linhai (China)

    2015-11-23

    This study investigated the value of computed tomography (CT) in the diagnosis and treatment of hepatic veno-occlusive disease (HVOD) caused by Sedum aizoon (SA). The clinical manifestations, treatment results, imaging findings, and histological findings of the liver were analyzed in 39 patients with HVOD caused by SA. Hepatomegaly, liver dysfunction, abdominal effusion, and geographic density changes on liver CT scans were found in all 39 patients. The pathological findings of histological liver examination included swelling and point-like necrosis of liver cells, significant expansion and congestion of the sinuses, endothelial swelling, and wall thickening with incomplete lumen occlusion of small liver vessels. CT geographic density changes were confirmed by histological examination of the liver in 18 patients. Sixteen patients with small amounts of ascites that started within 4 weeks of treatment recovered completely or significantly improved after symptomatic and supportive treatment. However, only 43.75% of the patients with larger amounts of ascites improved following symptomatic and supportive treatment. In conclusion, liver CT examination is a valuable, safe, and noninvasive tool for the diagnosis of HVOD caused by SA. In selected cases, liver CT examination may replace liver biopsy and histological analysis.

  6. Correlations between computed tomography findings and clinical manifestations of Streptococcus pneumoniae pneumonia

    International Nuclear Information System (INIS)

    Yagihashi, Kunihiro; Kurihara, Yasuyuki; Fujikawa, Atsuko; Matsuoka, Shin; Nakajima, Yasuo

    2011-01-01

    The aim of this study was to characterize the imaging features and compare computed tomography (CT) findings with clinical features of patients with Streptococcus pneumoniae pneumonia. We retrospectively reviewed 75 patients (44 men, 31 women; mean age 67 years) diagnosed with S. pneumoniae pneumonia who underwent chest CT scanning at our institution between January 2007 and August 2008. Diagnoses were based on detection of the S. pneumoniae antigen in urine. Chest CT scans revealed abnormalities in all patients. The predominant opacity patterns were an airspace pneumonia pattern (48%) and a bronchopneumonia pattern (48%), followed by an interstitial pneumonia pattern (4%). Consolidation was observed most frequently (84%) followed by ground glass opacity (82.7%), bronchial wall thickening (61.3%), and centrilobular nodules (49.3%). Airway dilatation (21.6%), pleural effusion (33.3%), lymphadenopathy (34.8%), and pulmonary emphysema (21.3%) were also observed. Pulmonary emphysema was significantly less frequent in patients with the bronchopneumonia pattern than in those without (p=0.007). The clinical features and CT findings did not differ significantly. CT image analysis showed that patients with S. pneumoniae pneumonia exhibited the bronchopneumonia and airspace pneumonia patterns with equal frequency. Bronchopneumonia pattern was less common in patients with preexisting emphysema. (author)

  7. Neural Correlates of Racial Ingroup Bias in Observing Computer-Animated Social Encounters

    Directory of Open Access Journals (Sweden)

    Yuta Katsumi

    2018-01-01

    Full Text Available Despite evidence for the role of group membership in the neural correlates of social cognition, the mechanisms associated with processing non-verbal behaviors displayed by racially ingroup vs. outgroup members remain unclear. Here, 20 Caucasian participants underwent fMRI recording while observing social encounters with ingroup and outgroup characters displaying dynamic and static non-verbal behaviors. Dynamic behaviors included approach and avoidance behaviors, preceded or not by a handshake; both dynamic and static behaviors were followed by participants’ ratings. Behaviorally, participants showed bias toward their ingroup members, demonstrated by faster/slower reaction times for evaluating ingroup static/approach behaviors, respectively. At the neural level, despite overall similar responses in the action observation network to ingroup and outgroup encounters, the medial prefrontal cortex showed dissociable activation, possibly reflecting spontaneous processing of ingroup static behaviors and positive evaluations of ingroup approach behaviors. The anterior cingulate and superior frontal cortices also showed sensitivity to race, reflected in coordinated and reduced activation for observing ingroup static behaviors. Finally, the posterior superior temporal sulcus showed uniquely increased activity to observing ingroup handshakes. These findings shed light on the mechanisms of racial ingroup bias in observing social encounters, and have implications for understanding factors related to successful interactions with individuals from diverse backgrounds.

  8. Influence of retrospective sorting on image quality in respiratory correlated computed tomography

    International Nuclear Information System (INIS)

    Guckenberger, Matthias; Weininger, Markus; Wilbert, Juergen; Richter, Anne; Baier, Kurt; Krieger, Thomas; Polat, Buelent; Flentje, Michael

    2007-01-01

    Purpose: To evaluate the influence of retrospective sorting on image quality in four-dimensional respiratory correlated CT. Materials and methods: Twelve patients with intrapulmonary tumors were examined using a 24-slice CT-scanner in helical mode. Images were reconstructed after retrospective sorting based on five algorithms: amplitude-based sorting with definition of peak-exhalation and peak-inhalation separately/locally for all breathing cycles (LAS) and globally for the time of image acquisition (GAS). Drifts of the breathing signal were corrected in dc-GAS. In phase-based (PS) and cycle-based (CS) algorithm the projections were sorted relative to time. Motion artifacts were scored by a radiologist. The tumor volumes were measured using automatic image segmentation. Results: Averaged over all breathing phases, LAS and PS achieved significantly improved image quality and lowest tumor volume variability compared to GAS, dc-GAS and CS. Imaging redundancy of 5 s was not sufficient for GAS and dc-GAS: missing corresponding amplitude positions in one or several breathing cycles resulted in incomplete reconstruction of peak-ventilation images in 11/12 and 10/12 patients with GAS and dc-GAS, respectively. Limiting the analysis to mid-ventilation phases showed GAS and dc-GAS as the most reliable algorithms. Conclusions: LAS and PS are suggested as a compromise between image quality and radiation dose

  9. Computational Study of Correlated Domain Motions in the AcrB Efflux Transporter

    Directory of Open Access Journals (Sweden)

    Robert Schulz

    2015-01-01

    Full Text Available As active part of the major efflux system in E. coli bacteria, AcrB is responsible for the uptake and pumping of toxic substrates from the periplasm toward the extracellular space. In combination with the channel protein TolC and membrane fusion protein AcrA, this efflux pump is able to help the bacterium to survive different kinds of noxious compounds. With the present study we intend to enhance the understanding of the interactions between the domains and monomers, for example, the transduction of mechanical energy from the transmembrane domain into the porter domain, correlated motions of different subdomains within monomers, and cooperative effects between monomers. To this end, targeted molecular dynamics simulations have been employed either steering the whole protein complex or specific parts thereof. By forcing only parts of the complex towards specific conformational states, the risk for transient artificial conformations during the simulations is reduced. Distinct cooperative effects between the monomers in AcrB have been observed. Possible allosteric couplings have been identified providing microscopic insights that might be exploited to design more efficient inhibitors of efflux systems.

  10. Memory architecture for efficient utilization of SDRAM: a case study of the computation/memory access trade-off

    DEFF Research Database (Denmark)

    Gleerup, Thomas Møller; Holten-Lund, Hans Erik; Madsen, Jan

    2000-01-01

    . In software, forward differencing is usually better, but in this hardware implementation, the trade-off has made it possible to develop a very regular memory architecture with a buffering system, which can reach 95% bandwidth utilization using off-the-shelf SDRAM, This is achieved by changing the algorithm......This paper discusses the trade-off between calculations and memory accesses in a 3D graphics tile renderer for visualization of data from medical scanners. The performance requirement of this application is a frame rate of 25 frames per second when rendering 3D models with 2 million triangles, i...... to use a memory access strategy with write-only and read-only phases, and a buffering system, which uses round-robin bank write-access combined with burst read-access....

  11. Kymogram detection and kymogram-correlated image reconstruction from subsecond spiral computed tomography scans of the heart

    International Nuclear Information System (INIS)

    Kachelriess, Marc; Sennst, Dirk-Alexander; Maxlmoser, Wolfgang; Kalender, Willi A.

    2002-01-01

    Subsecond single-slice, multi-slice or cone-beam spiral computed tomography (SSCT, MSCT, CBCT) offer great potential for improving heart imaging. Together with the newly developed phase-correlated cardiac reconstruction algorithms 180 deg. MCD and 180 deg. MCI [Med. Phys. 27, 1881-1902 (2000)] or related algorithms provided by the CT manufacturers, high image quality can be achieved. These algorithms require information about the cardiac motion, i.e., typically the simultaneously recorded electrocardiogram (ECG), to synchronize the reconstruction with the cardiac motion. Neither data acquired without ECG information (standard patients) nor acquisitions with corrupted ECG information can be handled adequately. We developed a method to extract the appropriate information about cardiac motion directly from the measured raw data (projection data). The so-called kymogram function is a measure of the cardiac motion as a function of time t or as a function of the projection angle α. In contrast to the ECG which is a global measure of the heart's electric excitation, the kymogram is a local measure of the heart motion at the z-position z(α) at projection angle α. The patient's local heart rate as well as the necessary synchronization information to be used with phase-correlated algorithms can be extracted from the kymogram by using a series of signal processing steps. The kymogram information is shown to be adequate to substitute the ECG information. Computer simulations with simulated ECG and patient measurements with simultaneously acquired ECG were carried out for a multislice scanner providing M=4 slices to evaluate these new approaches. Both the ECG function and the kymogram function were used for reconstruction. Both were highly correlated regarding the periodicity information used for reconstruction. In 21 out of 25 consecutive cases the kymogram approach was equivalent to the ECG-correlated reconstruction; only minor differences in image quality between both

  12. Cationic agent contrast-enhanced computed tomography imaging of cartilage correlates with the compressive modulus and coefficient of friction.

    Science.gov (United States)

    Lakin, B A; Grasso, D J; Shah, S S; Stewart, R C; Bansal, P N; Freedman, J D; Grinstaff, M W; Snyder, B D

    2013-01-01

    The aim of this study is to evaluate whether contrast-enhanced computed tomography (CECT) attenuation, using a cationic contrast agent (CA4+), correlates with the equilibrium compressive modulus (E) and coefficient of friction (μ) of ex vivo bovine articular cartilage. Correlations between CECT attenuation and E (Group 1, n = 12) and μ (Group 2, n = 10) were determined using 7 mm diameter bovine osteochondral plugs from the stifle joints of six freshly slaughtered, skeletally mature cows. The equilibrium compressive modulus was measured using a four-step, unconfined, compressive stress-relaxation test, and the coefficients of friction were determined from a torsional friction test. Following mechanical testing, samples were immersed in CA4+, imaged using μCT, rinsed, and analyzed for glycosaminoglycan (GAG) content using the 1,9-dimethylmethylene blue (DMMB) assay. The CECT attenuation was positively correlated with the GAG content of bovine cartilage (R(2) = 0.87, P coefficients of friction: CECT vs μ(static) (R(2) = 0.71, P = 0.002), CECT vs μ(static_equilibrium) (R(2) = 0.79, P coefficient of friction. Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  13. Tracheomalacia before and after aortosternopexy: dynamic and quantitative assessment by electron-beam computed tomography with clinical correlation

    International Nuclear Information System (INIS)

    Kao, S.C.S.; Kimura, K.; Smith, W.L.; Sato, Y.

    1995-01-01

    To correlate the dynamics of tracheal collapse with clinical upper airway obstruction before and after aortosternopexy, seven boys and three girls (mean age, 10 months) underwent dynamic evaluation of the trachea by electron-beam computed tomography (EBCT). The site, extent, and severity of collapse were correlated with symptomatology and details of operative procedure. When >50% area collapse was used as the criterion for tracheomalacia, segmental involvement occurred above the aortic arch in all patients, extending to the aortic arch level in only four. Tracheomalacia involved two or fewer 8-mm levels in seven patients and more than two levels in three. Eight patients underwent one aortosternopexy procedure, resulting in clinical improvement in six and correlating well with EBCT findings. Of the remaining two patients who had single aortosternopexy and did not show clinical and radiographic improvement, one required operative repair of a vascular ring and the other continued to have recurrent respiratory tract infections. On the basis of EBCT findings, two patients required additional innominate arteriopexies: One improved, and the other remained symptomatic, requiring tracheostomy. EBCT is a noninvasive modality that allows preoperative diagnosis of tracheomalacia. More importantly, the operative decision and technique are guided by an objective and quantitative assessment of tracheal collapse. (orig.)

  14. Medical Equipment Tele- and Condition-Based Maintenance with Enhanced Remote Diagnostic Access (RDA) and Computer Vision

    Science.gov (United States)

    2010-04-01

    failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE APR 2010 2. REPORT...The second is a ‘mechanical’ part that is controlled by circuit boards and is accessible by the technician via the serial console and running...was the use of conventional remote access solution designed for telecommuters or teleworkers in the Information Technology (IT) world, such as a

  15. Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

    International Nuclear Information System (INIS)

    Jodocy, Daniel; Aglan, Iman; Friedrich, Guy; Mallouhi, Ammar; Pachinger, Otmar; Jaschke, Werner; Feuchtner, Gudrun M.

    2010-01-01

    Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 ± 6.5 mm; depth, 2.6 ± 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p 50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

  16. Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

    International Nuclear Information System (INIS)

    Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E.; El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria; Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke; Kroft, Lucia J.; Younis, Imad Al; Reiber, Johan H.; Scholte, Arthur J.

    2013-01-01

    Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 ± 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS ≥2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p 2 = 20.7) and lesion length (χ 2 = 26.0) to the clinical variables and the visual assessment (χ 2 = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have incremental value over baseline variables and visually assessed significant stenosis. Potentially, QCT can refine assessment of CAD, which may be of potential use for identification of patients with myocardial ischaemia. (orig.)

  17. Clinical Correlates of Computationally Derived Visual Field Defect Archetypes in Patients from a Glaucoma Clinic.

    Science.gov (United States)

    Cai, Sophie; Elze, Tobias; Bex, Peter J; Wiggs, Janey L; Pasquale, Louis R; Shen, Lucy Q

    2017-04-01

    To assess the clinical validity of visual field (VF) archetypal analysis, a previously developed machine learning method for decomposing any Humphrey VF (24-2) into a weighted sum of clinically recognizable VF loss patterns. For each of 16 previously identified VF loss patterns ("archetypes," denoted AT1 through AT16), we screened 30,995 reliable VFs to select 10-20 representative patients whose VFs had the highest decomposition coefficients for each archetype. VF global indices and patient ocular and demographic features were extracted retrospectively. Based on resemblances between VF archetypes and clinically observed VF patterns, hypotheses were generated for associations between certain VF archetypes and clinical features, such as an association between AT6 (central island, representing severe VF loss) and large cup-to-disk ratio (CDR). Distributions of the selected clinical features were compared between representative eyes of certain archetypes and all other eyes using the two-tailed t-test or Fisher exact test. 243 eyes from 243 patients were included, representative of AT1 through AT16. CDR was more often ≥ 0.7 among eyes representative of AT6 (central island; p = 0.002), AT10 (inferior arcuate defect; p = 0.048), AT14 (superior paracentral defect; p = 0.016), and AT16 (inferior paracentral defect; p = 0.016) than other eyes. CDR was more often 6D (p = 0.069). Shared clinical features between computationally derived VF archetypes and clinically observed VF patterns support the clinical validity of VF archetypal analysis.

  18. Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

    Energy Technology Data Exchange (ETDEWEB)

    Jodocy, Daniel; Aglan, Iman [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Friedrich, Guy [Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Mallouhi, Ammar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Pachinger, Otmar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Jaschke, Werner [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Feuchtner, Gudrun M. [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria)], E-mail: gudrun.feuchtner@i-med.ac.at

    2010-01-15

    Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 {+-} 6.5 mm; depth, 2.6 {+-} 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p < 0.001); with a higher diameter reduction of 27% for end-systole compared to end-diastole with 15% (p = 0.006). Systolic LAD intramyocardial luminal narrowing >50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

  19. SCHEMA computational design of virus capsid chimeras: calibrating how genome packaging, protection, and transduction correlate with calculated structural disruption.

    Science.gov (United States)

    Ho, Michelle L; Adler, Benjamin A; Torre, Michael L; Silberg, Jonathan J; Suh, Junghae

    2013-12-20

    Adeno-associated virus (AAV) recombination can result in chimeric capsid protein subunits whose ability to assemble into an oligomeric capsid, package a genome, and transduce cells depends on the inheritance of sequence from different AAV parents. To develop quantitative design principles for guiding site-directed recombination of AAV capsids, we have examined how capsid structural perturbations predicted by the SCHEMA algorithm correlate with experimental measurements of disruption in seventeen chimeric capsid proteins. In our small chimera population, created by recombining AAV serotypes 2 and 4, we found that protection of viral genomes and cellular transduction were inversely related to calculated disruption of the capsid structure. Interestingly, however, we did not observe a correlation between genome packaging and calculated structural disruption; a majority of the chimeric capsid proteins formed at least partially assembled capsids and more than half packaged genomes, including those with the highest SCHEMA disruption. These results suggest that the sequence space accessed by recombination of divergent AAV serotypes is rich in capsid chimeras that assemble into 60-mer capsids and package viral genomes. Overall, the SCHEMA algorithm may be useful for delineating quantitative design principles to guide the creation of libraries enriched in genome-protecting virus nanoparticles that can effectively transduce cells. Such improvements to the virus design process may help advance not only gene therapy applications but also other bionanotechnologies dependent upon the development of viruses with new sequences and functions.

  20. Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); The Interuniversity Cardiology Institute of The Netherlands, Utrecht (Netherlands); El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Kroft, Lucia J. [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Younis, Imad Al [Leiden University Medical Center, Department of Nuclear Medicine, Leiden (Netherlands); Reiber, Johan H. [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Medis medical imaging systems B.V., Leiden (Netherlands); Scholte, Arthur J. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands)

    2013-08-15

    Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 {+-} 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS {>=}2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p < 0.001, and OR 1.07, 95 % CI 1.00-1.45, p = 0.032, respectively) after correcting for clinical variables and visually assessed significant stenosis. The addition of quantitatively assessed significant stenosis ({chi} {sup 2} = 20.7) and lesion length ({chi} {sup 2} = 26.0) to the clinical variables and the visual assessment ({chi} {sup 2} = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have

  1. Reduced HIV symptoms and improved health-related quality of life correlate with better access to care for HIV-1 infected women: the ELLA study.

    Science.gov (United States)

    Baran, Robert; Mulcahy, Fiona; Krznaric, Ivanka; Monforte, Antonella d'Arminio; Samarina, Anna; Xi, He; Cassetti, Isabel; Madruga, Jose Valdez; Zachry, Woodie; van Wyk, Jean; Martinez, Marisol

    2014-01-01

    Global HIV-1 prevalence is 35.3 million [1]; women comprise >50% of those infected. The majority of women may lack regular care and only one-fourth are virologically suppressed [2]. ELLA is a cross-sectional, non-interventional study conducted across Europe, Latin America, Canada and Asia that describes barriers to care for HIV-infected women and associations with disease stage, symptoms and health-related quality of life (HRQoL). HIV-infected women eligible for ELLA (≥18 years) completed: Barrier to Care Scale (BACS) comprising 12 items in four domains (Index range 0-12, Overall range 1-4, greater=more barriers, Overall score ≥2 considered severe); AIDS Clinical Trials Group (ACTG) Health Status Assessment comprising 21 items assessing 9 HRQoL domains (range 0-100, greater=better); and ACTG Symptom Distress Module comprising 20 symptoms rated on bother (range 0-4, greater=more bother). Healthcare providers documented medical history and HIV clinical data. Correlations of BACS response and last reported VL/CD4 count with HIV symptoms and HRQoL were analyzed. Spearman rank order was used to test correlations with statistical significance set at p50 years); 47.7% education HIV was acquired heterosexually in 83.0%; 88.2% of subjects were on ART; 57.5% had VLsymptom count and less symptom bother (psymptom count and less symptom bother correlated with better HRQoL on all nine domains (pHIV symptoms and less bother (pHIV-infected women, reduced barriers to care correlated with fewer symptoms, less symptom bother and better HRQoL. Improved HRQoL may be mediated by greater CD4 counts and fewer symptoms. Better access to care may improve HRQoL outcomes in this population.

  2. Remote Forensics May Bring the Next Sea Change in E-discovery: Are All Networked Computers Now Readily Accessible Under the Revised Federal Rules of Civil Procedure?

    Directory of Open Access Journals (Sweden)

    AleJoseph J. Schwerha

    2008-09-01

    Full Text Available The recent amendments to Rule 26 of the Federal Rules of Civil Procedure created a two-tiered approach to discovery of electronically stored information (“ESI”. Responding parties must produce ESI that is relevant, not subject to privilege, and reasonably accessible. However, because some methods of storing ESI, such as on magnetic backup tapes and within enormous databases, require substantial cost to access and search their contents, the rules permit parties to designate those repositories as “not reasonably accessible” because of undue burden or cost. But even despite the difficulty in searching for ESI, the party’s duty to preserve potentially responsive evidence remains; it simply gains the option to forgo poring over the material. Further, the court might nevertheless compel production if the requesting party demonstrates good cause.Regardless of whether the responding party believes certain documents to be reasonably accessible or not, courts may still require their production.   In such cases, the court may then choose to order production, but shift the costs of doing so to the requesting party.  Throughout this process, the burden and cost of production are central themes.   Their determination is fluid, varying from case to case and even over time in the same situation.   Nowhere is this more evident than where a responding party has numerous, geographically dispersed computers under its control that may contain responsive ESI to a request for production of documents.  Traditionally, a responding party would be forced to make a decision of whether or not to send out computer forensic experts to all of these locations to make forensically sound copies of all of those computers and then analyze each.   This process is time consuming and costly.  Recently, several companies have put forth substantial solutions that facially allow a responding party to capture and analyze data

  3. New developments in delivering public access to data from the National Center for Computational Toxicology at the EPA

    Science.gov (United States)

    Researchers at EPA’s National Center for Computational Toxicology integrate advances in biology, chemistry, and computer science to examine the toxicity of chemicals and help prioritize chemicals for further research based on potential human health risks. The goal of this researc...

  4. Design of a Computer-Controlled, Random-Access Slide Projector Interface. Final Report (April 1974 - November 1974).

    Science.gov (United States)

    Kirby, Paul J.; And Others

    The design, development, test, and evaluation of an electronic hardware device interfacing a commercially available slide projector with a plasma panel computer terminal is reported. The interface device allows an instructional computer program to select slides for viewing based upon the lesson student situation parameters of the instructional…

  5. Concurrent use of data base and graphics computer workstations to provide graphic access to large, complex data bases for robotics control of nuclear surveillance and maintenance

    International Nuclear Information System (INIS)

    Dalton, G.R.; Tulenko, J.S.; Zhou, X.

    1990-01-01

    The University of Florida is part of a multiuniversity research effort, sponsored by the US Department of Energy which is under way to develop and deploy an advanced semi-autonomous robotic system for use in nuclear power stations. This paper reports on the development of the computer tools necessary to gain convenient graphic access to the intelligence implicit in a large complex data base such as that in a nuclear reactor plant. This program is integrated as a man/machine interface within the larger context of the total computerized robotic planning and control system. The portion of the project described here addresses the connection between the three-dimensional displays on an interactive graphic workstation and a data-base computer running a large data-base server program. Programming the two computers to work together to accept graphic queries and return answers on the graphic workstation is a key part of the interactive capability developed

  6. Prediction of the filtrate particle size distribution from the pore size distribution in membrane filtration: Numerical correlations from computer simulations

    Science.gov (United States)

    Marrufo-Hernández, Norma Alejandra; Hernández-Guerrero, Maribel; Nápoles-Duarte, José Manuel; Palomares-Báez, Juan Pedro; Chávez-Rojo, Marco Antonio

    2018-03-01

    We present a computational model that describes the diffusion of a hard spheres colloidal fluid through a membrane. The membrane matrix is modeled as a series of flat parallel planes with circular pores of different sizes and random spatial distribution. This model was employed to determine how the size distribution of the colloidal filtrate depends on the size distributions of both, the particles in the feed and the pores of the membrane, as well as to describe the filtration kinetics. A Brownian dynamics simulation study considering normal distributions was developed in order to determine empirical correlations between the parameters that characterize these distributions. The model can also be extended to other distributions such as log-normal. This study could, therefore, facilitate the selection of membranes for industrial or scientific filtration processes once the size distribution of the feed is known and the expected characteristics in the filtrate have been defined.

  7. Use of Respiratory-Correlated Four-Dimensional Computed Tomography to Determine Acceptable Treatment Margins for Locally Advanced Pancreatic Adenocarcinoma

    International Nuclear Information System (INIS)

    Goldstein, Seth D.; Ford, Eric C.; Duhon, Mario; McNutt, Todd; Wong, John; Herman, Joseph M.

    2010-01-01

    Purpose: Respiratory-induced excursions of locally advanced pancreatic adenocarcinoma could affect dose delivery. This study quantified tumor motion and evaluated standard treatment margins. Methods and Materials: Respiratory-correlated four-dimensional computed tomography images were obtained on 30 patients with locally advanced pancreatic adenocarcinoma; 15 of whom underwent repeat scanning before cone-down treatment. Treatment planning software was used to contour the gross tumor volume (GTV), bilateral kidneys, and biliary stent. Excursions were calculated according to the centroid of the contoured volumes. Results: The mean ± standard deviation GTV excursion in the superoinferior (SI) direction was 0.55 ± 0.23 cm; an expansion of 1.0 cm adequately accounted for the GTV motion in 97% of locally advanced pancreatic adenocarcinoma patients. Motion GTVs were generated and resulted in a 25% average volume increase compared with the static GTV. Of the 30 patients, 17 had biliary stents. The mean SI stent excursion was 0.84 ± 0.32 cm, significantly greater than the GTV motion. The xiphoid process moved an average of 0.35 ± 0.12 cm, significantly less than the GTV. The mean SI motion of the left and right kidneys was 0.65 ± 0.27 cm and 0.77 ± 0.30 cm, respectively. At repeat scanning, no significant changes were seen in the mean GTV size (p = .8) or excursion (p = .3). Conclusion: These data suggest that an asymmetric expansion of 1.0, 0.7, and 0.6 cm along the respective SI, anteroposterior, and medial-lateral directions is recommended if a respiratory-correlated four-dimensional computed tomography scan is not available to evaluate the tumor motion during treatment planning. Surrogates of tumor motion, such as biliary stents or external markers, should be used with caution.

  8. Computing Wigner distributions and time correlation functions using the quantum thermal bath method: application to proton transfer spectroscopy.

    Science.gov (United States)

    Basire, Marie; Borgis, Daniel; Vuilleumier, Rodolphe

    2013-08-14

    Langevin dynamics coupled to a quantum thermal bath (QTB) allows for the inclusion of vibrational quantum effects in molecular dynamics simulations at virtually no additional computer cost. We investigate here the ability of the QTB method to reproduce the quantum Wigner distribution of a variety of model potentials, designed to assess the performances and limits of the method. We further compute the infrared spectrum of a multidimensional model of proton transfer in the gas phase and in solution, using classical trajectories sampled initially from the Wigner distribution. It is shown that for this type of system involving large anharmonicities and strong nonlinear coupling to the environment, the quantum thermal bath is able to sample the Wigner distribution satisfactorily and to account for both zero point energy and tunneling effects. It leads to quantum time correlation functions having the correct short-time behavior, and the correct associated spectral frequencies, but that are slightly too overdamped. This is attributed to the classical propagation approximation rather than the generation of the quantized initial conditions themselves.

  9. Changes in functional brain organization and behavioral correlations after rehabilitative therapy using a brain-computer interface

    Directory of Open Access Journals (Sweden)

    Brittany Mei Young

    2014-07-01

    Full Text Available This study aims to examine the changes in task-related brain activity induced by rehabilitative therapy using brain-computer interface (BCI technologies and whether these changes are relevant to functional gains achieved through the use of these therapies. Stroke patients with persistent upper-extremity motor deficits received interventional rehabilitation therapy using a closed-loop neurofeedback BCI device (n=8 or no therapy (n=6. Behavioral assessments using the Stroke Impact Scale, the Action Research Arm Test, and the Nine-Hole Peg Test as well as task-based fMRI scans were conducted before, during, after, and one month after therapy administration or at analogous intervals in the absence of therapy. Laterality Index (LI during finger tapping of each hand were calculated for each time point and assessed for correlation with behavioral outcomes. Brain activity during finger tapping of each hand shifted over the course of BCI therapy but not in the absence of therapy to greater involvement of the non-lesioned hemisphere (and lesser involvement of the stroke-lesioned hemisphere as measured by LI. Moreover, changes from baseline LI values during finger tapping of the impaired hand were correlated with gains in both objective and subjective behavioral measures. These findings suggest that the administration of interventional BCI therapy can induce differential changes in brain activity patterns between the lesioned and nonlesioned hemisphere and that these brain changes are associated with changes in specific motor functions.

  10. Thallium-201 single photon emission computed tomography (SPECT) in patients with Duchenne's progressive muscular dystrophy. A histopathologic correlation study

    International Nuclear Information System (INIS)

    Nishimura, Toru; Yanagisawa, Atsuo; Sakata, Konomi; Shimoyama, Katsuya; Yoshino, Hideaki; Ishikawa, Kyozo; Sakata, Hitomi; Ishihara, Tadayuki

    2001-01-01

    The pathomorphologic mechanism responsible for abnormal perfusion imaging during thallium-201 myocardial single photon emission computed tomography ( 201 Tl-SPECT) in patients with Duchenne's progressive muscular dystrophy (DMD) was investigated. Hearts from 7 patients with DMD were evaluated histopathologically at autopsy and the results correlated with findings on initial and delayed resting 201 Tl-SPECT images. The location of segments with perfusion defects correlated with the histopathologically abnormal segments in the hearts. Both the extent and degree of myocardial fibrosis were severe, especially in the posterolateral segment of the left ventricle. Severe transmural fibrosis and severe fatty infiltration were common in segments with perfusion defects. In areas of redistribution, the degree of fibrosis appeared to be greater than in areas of normal perfusion; and intermuscular edema was prominent. Thus, the degree and extent of perfusion defects detected by 201 Tl-SPECT were compatible with the histopathology. The presence of the redistribution phenomenon may indicate ongoing fibrosis. Initial and delayed resting 201 Tl-SPECT images can predict the site and progress of myocardial degeneration in patients with DMD. (author)

  11. EEG correlates of P300-based brain-computer interface (BCI) performance in people with amyotrophic lateral sclerosis

    Science.gov (United States)

    Mak, Joseph N.; McFarland, Dennis J.; Vaughan, Theresa M.; McCane, Lynn M.; Tsui, Phillippa Z.; Zeitlin, Debra J.; Sellers, Eric W.; Wolpaw, Jonathan R.

    2012-04-01

    The purpose of this study was to identify electroencephalography (EEG) features that correlate with P300-based brain-computer interface (P300 BCI) performance in people with amyotrophic lateral sclerosis (ALS). Twenty people with ALS used a P300 BCI spelling application in copy-spelling mode. Three types of EEG features were found to be good predictors of P300 BCI performance: (1) the root-mean-square amplitude and (2) the negative peak amplitude of the event-related potential to target stimuli (target ERP) at Fz, Cz, P3, Pz, and P4; and (3) EEG theta frequency (4.5-8 Hz) power at Fz, Cz, P3, Pz, P4, PO7, PO8 and Oz. A statistical prediction model that used a subset of these features accounted for >60% of the variance in copy-spelling performance (p < 0.001, mean R2 = 0.6175). The correlations reflected between-subject, rather than within-subject, effects. The results enhance understanding of performance differences among P300 BCI users. The predictors found in this study might help in: (1) identifying suitable candidates for long-term P300 BCI operation; (2) assessing performance online. Further work on within-subject effects needs to be done to establish whether P300 BCI user performance could be improved by optimizing one or more of these EEG features.

  12. Lung Ultrasonography in Patients With Idiopathic Pulmonary Fibrosis: Evaluation of a Simplified Protocol With High-Resolution Computed Tomographic Correlation.

    Science.gov (United States)

    Vassalou, Evangelia E; Raissaki, Maria; Magkanas, Eleftherios; Antoniou, Katerina M; Karantanas, Apostolos H

    2018-03-01

    To compare a simplified ultrasonographic (US) protocol in 2 patient positions with the same-positioned comprehensive US assessments and high-resolution computed tomographic (CT) findings in patients with idiopathic pulmonary fibrosis. Twenty-five consecutive patients with idiopathic pulmonary fibrosis were prospectively enrolled and examined in 2 sessions. During session 1, patients were examined with a US protocol including 56 lung intercostal spaces in supine/sitting (supine/sitting comprehensive protocol) and lateral decubitus (decubitus comprehensive protocol) positions. During session 2, patients were evaluated with a 16-intercostal space US protocol in sitting (sitting simplified protocol) and left/right decubitus (decubitus simplified protocol) positions. The 16 intercostal spaces were chosen according to the prevalence of idiopathic pulmonary fibrosis-related changes on high-resolution CT. The sum of B-lines counted in each intercostal space formed the US scores for all 4 US protocols: supine/sitting and decubitus comprehensive US scores and sitting and decubitus simplified US scores. High-resolution CT-related Warrick scores (J Rheumatol 1991; 18:1520-1528) were compared to US scores. The duration of each protocol was recorded. A significant correlation was found between all US scores and Warrick scores and between simplified and corresponding comprehensive scores (P idiopathic pulmonary fibrosis. The 16-intercostal space simplified protocol in the lateral decubitus position correlated better with high-resolution CT findings and was less time-consuming compared to the sitting position. © 2017 by the American Institute of Ultrasound in Medicine.

  13. Changes in functional connectivity correlate with behavioral gains in stroke patients after therapy using a brain-computer interface device

    Directory of Open Access Journals (Sweden)

    Brittany Mei Young

    2014-07-01

    Full Text Available Brain-computer interface (BCI technology is being incorporated into new stroke rehabilitation devices, but little is known about brain changes associated with its use. We collected anatomical and functional MRI of 9 stroke patients with persistent upper extremity motor impairment before, during, and after therapy using a BCI system. Subjects were asked to perform finger tapping of the impaired hand during fMRI. Action Research Arm Test (ARAT, 9-Hole Peg Test (9-HPT, and Stroke Impact Scale (SIS domains of Hand Function (HF and Activities of Daily Living (ADL were also assessed. Group-level analyses examined changes in whole-brain task-based functional connectivity (FC to seed regions in the motor network observed during and after BCI therapy. Whole-brain FC analyses seeded in each thalamus showed FC increases from baseline at mid-therapy and post-therapy (p< 0.05. Changes in FC between seeds at both the network and the connection levels were examined for correlations with changes in behavioral measures. Average motor network FC was increased post-therapy, and changes in average network FC correlated (p < 0.05 with changes in performance on ARAT (R2=0.21, 9-HPT (R2=0.41, SIS HF (R2=0.27, and SIS ADL (R2=0.40. Multiple individual connections within the motor network were found to correlate in change from baseline with changes in behavioral measures. Many of these connections involved the thalamus, with change in each of four behavioral measures significantly correlating with change from baseline FC of at least one thalamic connection. These preliminary results show changes in FC that occur with the administration of rehabilitative therapy using a BCI system. The correlations noted between changes in FC measures and changes in behavioral outcomes indicate that both adaptive and maladaptive changes in FC may develop with this therapy and also suggest a brain-behavior relationship that may be stimulated by the neuromodulatory component of BCI therapy.

  14. Bone mineral density (BMD) and computer tomographic measurements of the equine proximal phalanx in correlation with breaking strength.

    Science.gov (United States)

    Tóth, P; Horváth, C; Ferencz, V; Tóth, B; Váradi, A; Szenci, O; Bodó, G

    2013-01-01

    Despite the fact that bone mineral density (BMD) is an important fracture risk predictor in human medicine, studies in equine orthopedic research are still lacking. We hypothesized that BMD correlates with bone failure and fatigue fractures of this bone. Thus, the objectives of this study were to measure the structural and mechanical properties of the proximal phalanx with dual energy X-ray absorptiometry (DXA), to correlate the data obtained from DXA and computer tomography (CT) measurements to those obtained by loading pressure examination and to establish representative region of interest (ROI) for in vitro BMD measurements of the equine proximal phalanx for predicting bone failure force. DXA was used to measure the whole bone BMD and additional three ROI sites in 14 equine proximal phalanges. Following evaluation of the bone density, whole bone, cortical width and area in the mid-diaphyseal plane were measured on CT images. Bones were broken using a manually controlled universal bone crusher to measure bone failure force and reevaluated for the site of fractures on follow-up CT images. Compressive load was applied at a constant displacement rate of 2 mm/min until failure, defined as the first clear drop in the load measurement. The lowest BMD was measured at the trabecular region (mean +/- SD: 1.52 +/- 0.12 g/cm2; median: 1.48 g/cm2; range: 1.38-1.83 g/cm2). There was a significant positive linear correlation between trabelcular BMD and the breaking strength (P = 0.023, r = 0.62). The trabecular region of the proximal phalanx appears to be the only significant indicator of failure of strength in vitro. This finding should be reassessed to further reveal the prognostic value of trabecular BMD in an in vivo fracture risk model.

  15. The effects of home computer access and social capital on mathematics and science achievement among Asian-American high school students in the NELS:88 data set

    Science.gov (United States)

    Quigley, Mark Declan

    The purpose of this researcher was to examine specific environmental, educational, and demographic factors and their influence on mathematics and science achievement. In particular, the researcher ascertained the interconnections of home computer access and social capital, with Asian American students and the effect on mathematics and science achievement. Coleman's theory on social capital and parental influence was used as a basis for the analysis of data. Subjects for this study were the base year students from the National Education Longitudinal Study of 1988 (NELS:88) and the subsequent follow-up survey data in 1990, 1992, and 1994. The approximate sample size for this study is 640 ethnic Asians from the NELS:88 database. The analysis was a longitudinal study based on the Student and Parent Base Year responses and the Second Follow-up survey of 1992, when the subjects were in 12th grade. Achievement test results from the NELS:88 data were used to measure achievement in mathematics and science. The NELS:88 test battery was developed to measure both individual status and a student's growth in a number of achievement areas. The subject's responses were analyzed by principal components factor analysis, weights, effect sizes, hierarchial regression analysis, and PLSPath Analysis. The results of this study were that prior ability in mathematics and science is a major influence in the student's educational achievement. Findings from the study support the view that home computer access has a negative direct effect on mathematics and science achievement for both Asian American males and females. None of the social capital factors in the study had either a negative or positive direct effect on mathematics and science achievement although some indirect effects were found. Suggestions were made toward increasing parental involvement in their children's academic endeavors. Computer access in the home should be considered related to television viewing and should be closely

  16. Computational experiment for the purpose of determining the probabilistic and temporal characteristics of information security systems against unauthorized access in automated information systems

    Directory of Open Access Journals (Sweden)

    A. V. Skrypnikov

    2017-01-01

    Full Text Available The article is devoted to the method of experimental estimation of parameters of functioning of standard information protection systems from unauthorized access, certified, widely used in organizations operating automated information systems. In the course of the experiment, statistical data were evaluated in the dynamics of the functioning of information security systems against unauthorized access in automated information systems. Registration of the parameters for the execution time of protective protection functions was carried out using a special utility called ProcessMonitor from the Sysinternals suite of utilities used to filter processes and threads. The loading of the processor and main memory of the computer with the use of special software, specially designed for performing experimental research, simulates the operation of GIS in real-world work for its intended purpose. A special software for simulating the work of a system with high load is developed in "VisualStudio 2015" within the framework of "ConsoleApplication". At the same time, the processor is loaded at a level of 50-70% and 60-80% of the operative memory. The obtained values of the time of implementation of protective functions in conditions of high utilization of resources of computer facilities for their intended purpose will allow us to assess the conflict and dynamic properties of the GIS. In the future, the obtained experimental estimates can be used to develop a model of information security in automated information systems, as well as in the formation of quality requirements (resource intensity, response time to the user's request, availability, etc.. Also, the results of the computational experiment in the future can be used to develop a software package for assessing the dynamic performance of information security systems against unauthorized access in automated information systems

  17. COMPUTING

    CERN Multimedia

    M. Kasemann

    Overview In autumn the main focus was to process and handle CRAFT data and to perform the Summer08 MC production. The operational aspects were well covered by regular Computing Shifts, experts on duty and Computing Run Coordination. At the Computing Resource Board (CRB) in October a model to account for service work at Tier 2s was approved. The computing resources for 2009 were reviewed for presentation at the C-RRB. The quarterly resource monitoring is continuing. Facilities/Infrastructure operations Operations during CRAFT data taking ran fine. This proved to be a very valuable experience for T0 workflows and operations. The transfers of custodial data to most T1s went smoothly. A first round of reprocessing started at the Tier-1 centers end of November; it will take about two weeks. The Computing Shifts procedure was tested full scale during this period and proved to be very efficient: 30 Computing Shifts Persons (CSP) and 10 Computing Resources Coordinators (CRC). The shift program for the shut down w...

  18. Diagnostic accuracy of computer tomography angiography and magnetic resonance angiography in the stenosis detection of autologuous hemodialysis access: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Bin Li

    Full Text Available PURPOSE: To compare the diagnostic performances of computer tomography angiography (CTA and magnetic resonance angiography (MRA for detection and assessment of stenosis in patients with autologuous hemodialysis access. MATERIALS AND METHODS: Search of PubMed, MEDLINE, EMBASE and Cochrane Library database from January 1984 to May 2013 for studies comparing CTA or MRA with DSA or surgery for autologuous hemodialysis access. Eligible studies were in English language, aimed to detect more than 50% stenosis or occlusion of autologuous vascular access in hemodialysis patients with CTA and MRA technology and provided sufficient data about diagnosis performance. Methodological quality was assessed by the Quality Assessment of Diagnostic Studies (QUADAS instrument. Sensitivities (SEN, specificities (SPE, positive likelihood ratio (PLR, negative likelihood values (NLR, diagnostic odds ratio (DOR and areas under the receiver operator characteristic curve (AUC were pooled statistically. Potential threshold effect, heterogeneity and publication bias was evaluated. The clinical utility of CTA and MRA in detection of stenosis was also investigated. RESULT: Sixteen eligible studies were included, with a total of 500 patients. Both CTA and MRA were accurate modality (sensitivity, 96.2% and 95.4%, respectively; specificity, 97.1 and 96.1%, respectively; DOR [diagnostic odds ratio], 393.69 and 211.47, respectively for hemodialysis vascular access. No significant difference was detected between the diagnostic performance of CTA (AUC, 0.988 and MRA (AUC, 0.982. Meta-regression analyses and subgroup analyses revealed no statistical difference. The Deek's funnel plots suggested a publication bias. CONCLUSION: Diagnostic performance of CTA and MRA for detecting stenosis of hemodialysis vascular access had no statistical difference. Both techniques may function as an alternative or an important complement to conventional digital subtraction angiography (DSA and may be

  19. A Review of EEG-Based Brain-Computer Interfaces as Access Pathways for Individuals with Severe Disabilities

    Science.gov (United States)

    Moghimi, Saba; Kushki, Azadeh; Guerguerian, Anne Marie; Chau, Tom

    2013-01-01

    Electroencephalography (EEG) is a non-invasive method for measuring brain activity and is a strong candidate for brain-computer interface (BCI) development. While BCIs can be used as a means of communication for individuals with severe disabilities, the majority of existing studies have reported BCI evaluations by able-bodied individuals.…

  20. Guided access cavity preparation using cone-beam computed tomography and optical surface scans - an ex vivo study

    DEFF Research Database (Denmark)

    Buchgreitz, J; Buchgreitz, M; Mortensen, D

    2016-01-01

    AIM: To evaluate ex vivo, the accuracy of a preparation procedure planned for teeth with pulp canal obliteration (PCO) using a guide rail concept based on a cone-beam computed tomography (CBCT) scan merged with an optical surface scan. METHODOLOGY: A total of 48 teeth were mounted in acrylic bloc...

  1. Using Palm Technology in Participatory Simulations of Complex Systems: A New Take on Ubiquitous and Accessible Mobile Computing

    Science.gov (United States)

    Klopfer, Eric; Yoon, Susan; Perry, Judy

    2005-01-01

    This paper reports on teachers' perceptions of the educational affordances of a handheld application called Participatory Simulations. It presents evidence from five cases representing each of the populations who work with these computational tools. Evidence across multiple data sources yield similar results to previous research evaluations of…

  2. Correlation of Computed Tomography Imaging Features With Pain Response in Patients With Spine Metastases After Radiation Therapy

    International Nuclear Information System (INIS)

    Mitera, Gunita; Probyn, Linda; Ford, Michael; Donovan, Andrea; Rubenstein, Joel; Finkelstein, Joel; Christakis, Monique; Zhang, Liying; Campos, Sarah; Culleton, Shaelyn; Nguyen, Janet; Sahgal, Arjun; Barnes, Elizabeth; Tsao, May; Danjoux, Cyril; Holden, Lori; Yee, Albert; Khan, Luluel; Chow, Edward

    2011-01-01

    Purpose: To correlate computed tomography (CT) imaging features of spinal metastases with pain relief after radiotherapy (RT). Methods and Materials: Thirty-three patients receiving computed tomography (CT)-simulated RT for spinal metastases in an outpatient palliative RT clinic from January 2007 to October 2008 were retrospectively reviewed. Forty spinal metastases were evaluated. Pain response was rated using the International Bone Metastases Consensus Working Party endpoints. Three musculoskeletal radiologists and two orthopaedic surgeons evaluated CT features, including osseous and soft tissue tumor extent, presence of a pathologic fracture, severity of vertebral height loss, and presence of kyphosis. Results: The mean patient age was 69 years; 24 were men and 9 were women. The mean worst pain score was 7/10, and the mean total daily oral morphine equivalent was 77.3 mg. Treatment doses included 8 Gy in one fraction (22/33), 20 Gy in five fractions (10/33), and 20 Gy in eight fractions (1/33). The CT imaging appearance of spinal metastases included vertebral body involvement (40/40), pedicle involvement (23/40), and lamina involvement (18/40). Soft tissue component (10/40) and nerve root compression (9/40) were less common. Pathologic fractures existed in 11/40 lesions, with resultant vertebral body height loss in 10/40 and kyphosis in 2/40 lesions. At months 1, 2, and 3 after RT, 18%, 69%, and 70% of patients experienced pain relief. Pain response was observed with various CT imaging features. Conclusions: Pain response after RT did not differ in patients with and without pathologic fracture, kyphosis, or any other CT features related to extent of tumor involvement. All patients with painful spinal metastases may benefit from palliative RT.

  3. Characterization of cardiac quiescence from retrospective cardiac computed tomography using a correlation-based phase-to-phase deviation measure

    Energy Technology Data Exchange (ETDEWEB)

    Wick, Carson A.; McClellan, James H. [School of Electrical and Computer Engineering, Georgia Institute of Technology, 777 Atlantic Drive Northwest, Atlanta, Georgia 30332 (United States); Arepalli, Chesnal D. [Department of Radiology, University of British Columbia, 3350-950 West 10th Avenue, Vancouver, British Columbia V5Z 4E3 (Canada); Auffermann, William F.; Henry, Travis S. [Department of Radiology and Imaging Sciences, Emory University, Division of Cardiothoracic Imaging, 1364 Clifton Road Northeast, Suite 309, Atlanta, Georgia 30322 (United States); Khosa, Faisal [Department of Radiology and Imaging Sciences, Emory University, Division of Emergency Radiology, 550 Peachtree Street Northeast, Atlanta, Georgia 30308 (United States); Coy, Adam M. [School of Medicine, Emory University, 100 Woodruff Circle, Atlanta, Georgia 30322 (United States); Tridandapani, Srini, E-mail: stridan@emory.edu [Department of Radiology and Imaging Sciences, Emory University, Winship Cancer Institute, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, Georgia 30322 and School of Electrical and Computer Engineering, Georgia Institute of Technology, 777 Atlantic Drive Northwest, Atlanta, Georgia 30332 (United States)

    2015-02-15

    Purpose: Accurate knowledge of cardiac quiescence is crucial to the performance of many cardiac imaging modalities, including computed tomography coronary angiography (CTCA). To accurately quantify quiescence, a method for detecting the quiescent periods of the heart from retrospective cardiac computed tomography (CT) using a correlation-based, phase-to-phase deviation measure was developed. Methods: Retrospective cardiac CT data were obtained from 20 patients (11 male, 9 female, 33–74 yr) and the left main, left anterior descending, left circumflex, right coronary artery (RCA), and interventricular septum (IVS) were segmented for each phase using a semiautomated technique. Cardiac motion of individual coronary vessels as well as the IVS was calculated using phase-to-phase deviation. As an easily identifiable feature, the IVS was analyzed to assess how well it predicts vessel quiescence. Finally, the diagnostic quality of the reconstructed volumes from the quiescent phases determined using the deviation measure from the vessels in aggregate and the IVS was compared to that from quiescent phases calculated by the CT scanner. Three board-certified radiologists, fellowship-trained in cardiothoracic imaging, graded the diagnostic quality of the reconstructions using a Likert response format: 1 = excellent, 2 = good, 3 = adequate, 4 = nondiagnostic. Results: Systolic and diastolic quiescent periods were identified for each subject from the vessel motion calculated using the phase-to-phase deviation measure. The motion of the IVS was found to be similar to the aggregate vessel (AGG) motion. The diagnostic quality of the coronary vessels for the quiescent phases calculated from the aggregate vessel (P{sub AGG}) and IVS (P{sub IV} {sub S}) deviation signal using the proposed methods was comparable to the quiescent phases calculated by the CT scanner (P{sub CT}). The one exception was the RCA, which improved for P{sub AGG} for 18 of the 20 subjects when compared to P

  4. Filter bank canonical correlation analysis for implementing a high-speed SSVEP-based brain-computer interface

    Science.gov (United States)

    Chen, Xiaogang; Wang, Yijun; Gao, Shangkai; Jung, Tzyy-Ping; Gao, Xiaorong

    2015-08-01

    Objective. Recently, canonical correlation analysis (CCA) has been widely used in steady-state visual evoked potential (SSVEP)-based brain-computer interfaces (BCIs) due to its high efficiency, robustness, and simple implementation. However, a method with which to make use of harmonic SSVEP components to enhance the CCA-based frequency detection has not been well established. Approach. This study proposed a filter bank canonical correlation analysis (FBCCA) method to incorporate fundamental and harmonic frequency components to improve the detection of SSVEPs. A 40-target BCI speller based on frequency coding (frequency range: 8-15.8 Hz, frequency interval: 0.2 Hz) was used for performance evaluation. To optimize the filter bank design, three methods (M1: sub-bands with equally spaced bandwidths; M2: sub-bands corresponding to individual harmonic frequency bands; M3: sub-bands covering multiple harmonic frequency bands) were proposed for comparison. Classification accuracy and information transfer rate (ITR) of the three FBCCA methods and the standard CCA method were estimated using an offline dataset from 12 subjects. Furthermore, an online BCI speller adopting the optimal FBCCA method was tested with a group of 10 subjects. Main results. The FBCCA methods significantly outperformed the standard CCA method. The method M3 achieved the highest classification performance. At a spelling rate of ˜33.3 characters/min, the online BCI speller obtained an average ITR of 151.18 ± 20.34 bits min-1. Significance. By incorporating the fundamental and harmonic SSVEP components in target identification, the proposed FBCCA method significantly improves the performance of the SSVEP-based BCI, and thereby facilitates its practical applications such as high-speed spelling.

  5. Quantification of subarachnoid hemorrhage by three-dimensional computed tomography. Correlation between hematoma volume and symptomatic vasospasm

    International Nuclear Information System (INIS)

    Sato, Taku; Sakuma, Jun; Sasaki, Tatsuya

    2011-01-01

    Subarachnoid hemorrhage (SAH) volume was measured by three-dimensional computed tomography (3D-CT) and the correlation examined between the SAH volume and the occurrence of symptomatic vasospasm (SVS). Experimental (in vitro) hematomas were made with blood obtained from 10 volunteers. The hematoma volume was determined by actual measurements and by 3D-CT using a CT number in the range of 40-80 Hounsfield units (HU) on days 1, 4, 7, 11, and 14. The coefficients on days 1 and 4 were relatively high and the correlation between measured and estimated volumes was significant on days 7, 11, and 14. 3D-CT was also performed in 50 patients with SAH at onset (day 0) and on days 1, 4, 7, and 14. The hematoma volume including the volume of normal structures was automatically calculated (V1). The volume of normal structures (V2) with CT numbers of 40-80 HU was calculated in another 50 patients without intracranial lesions as 12 ml. The total hematoma volume was defined as V1 minus mean V2. The mean SAH volume was 44, 36, 21, 11, and 8 ml on days 0, 1, 4, 7, and 14, respectively. The hematoma volumes were significantly larger in patients with SVS than in patients without SVS at all time points. The minimum hematoma volume in patients with SVS was 92, 76, 42, 24, and 12 ml on days 0, 1, 4, 7, and 14, respectively. This method allows the quantitative determination of SAH volume based on 3D-CT, and may be useful in clinical studies of cerebral vasospasm. (author)

  6. Multichannel analyzer using the direct-memory-access channel in a personal computer; Mnogokanal`nyj analizator v personal`nom komp`yutere, ispol`zuyushchij kanal pryamogo dostupa k pamyati

    Energy Technology Data Exchange (ETDEWEB)

    Georgiev, G; Vankov, I; Dimitrov, L [Incn. Yadernykh Issledovanij i Yadernoj Ehnergetiki Bolgarskoj Akademii Nuk, Sofiya (Bulgaria); Peev, I [Firma TOIVEL, Sofiya (Bulgaria)

    1996-12-31

    Paper describes a multichannel analyzer of the spectrometry data developed on the basis of a personal computer memory and a controlled channel of direct access. Analyzer software covering a driver and program of spectrum display control is studied. 2 figs.

  7. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction CMS distributed computing system performed well during the 2011 start-up. The events in 2011 have more pile-up and are more complex than last year; this results in longer reconstruction times and harder events to simulate. Significant increases in computing capacity were delivered in April for all computing tiers, and the utilisation and load is close to the planning predictions. All computing centre tiers performed their expected functionalities. Heavy-Ion Programme The CMS Heavy-Ion Programme had a very strong showing at the Quark Matter conference. A large number of analyses were shown. The dedicated heavy-ion reconstruction facility at the Vanderbilt Tier-2 is still involved in some commissioning activities, but is available for processing and analysis. Facilities and Infrastructure Operations Facility and Infrastructure operations have been active with operations and several important deployment tasks. Facilities participated in the testing and deployment of WMAgent and WorkQueue+Request...

  8. COMPUTING

    CERN Multimedia

    P. McBride

    The Computing Project is preparing for a busy year where the primary emphasis of the project moves towards steady operations. Following the very successful completion of Computing Software and Analysis challenge, CSA06, last fall, we have reorganized and established four groups in computing area: Commissioning, User Support, Facility/Infrastructure Operations and Data Operations. These groups work closely together with groups from the Offline Project in planning for data processing and operations. Monte Carlo production has continued since CSA06, with about 30M events produced each month to be used for HLT studies and physics validation. Monte Carlo production will continue throughout the year in the preparation of large samples for physics and detector studies ramping to 50 M events/month for CSA07. Commissioning of the full CMS computing system is a major goal for 2007. Site monitoring is an important commissioning component and work is ongoing to devise CMS specific tests to be included in Service Availa...

  9. COMPUTING

    CERN Multimedia

    M. Kasemann

    Overview During the past three months activities were focused on data operations, testing and re-enforcing shift and operational procedures for data production and transfer, MC production and on user support. Planning of the computing resources in view of the new LHC calendar in ongoing. Two new task forces were created for supporting the integration work: Site Commissioning, which develops tools helping distributed sites to monitor job and data workflows, and Analysis Support, collecting the user experience and feedback during analysis activities and developing tools to increase efficiency. The development plan for DMWM for 2009/2011 was developed at the beginning of the year, based on the requirements from the Physics, Computing and Offline groups (see Offline section). The Computing management meeting at FermiLab on February 19th and 20th was an excellent opportunity discussing the impact and for addressing issues and solutions to the main challenges facing CMS computing. The lack of manpower is particul...

  10. Use of 4-Dimensional Computed Tomography-Based Ventilation Imaging to Correlate Lung Dose and Function With Clinical Outcomes

    International Nuclear Information System (INIS)

    Vinogradskiy, Yevgeniy; Castillo, Richard; Castillo, Edward; Tucker, Susan L.; Liao, Zhongxing; Guerrero, Thomas; Martel, Mary K.

    2013-01-01

    Purpose: Four-dimensional computed tomography (4DCT)-based ventilation is an emerging imaging modality that can be used in the thoracic treatment planning process. The clinical benefit of using ventilation images in radiation treatment plans remains to be tested. The purpose of the current work was to test the potential benefit of using ventilation in treatment planning by evaluating whether dose to highly ventilated regions of the lung resulted in increased incidence of clinical toxicity. Methods and Materials: Pretreatment 4DCT data were used to compute pretreatment ventilation images for 96 lung cancer patients. Ventilation images were calculated using 4DCT data, deformable image registration, and a density-change based algorithm. Dose–volume and ventilation-based dose function metrics were computed for each patient. The ability of the dose–volume and ventilation-based dose–function metrics to predict for severe (grade 3+) radiation pneumonitis was assessed using logistic regression analysis, area under the curve (AUC) metrics, and bootstrap methods. Results: A specific patient example is presented that demonstrates how incorporating ventilation-based functional information can help separate patients with and without toxicity. The logistic regression significance values were all lower for the dose–function metrics (range P=.093-.250) than for their dose–volume equivalents (range, P=.331-.580). The AUC values were all greater for the dose–function metrics (range, 0.569-0.620) than for their dose–volume equivalents (range, 0.500-0.544). Bootstrap results revealed an improvement in model fit using dose–function metrics compared to dose–volume metrics that approached significance (range, P=.118-.155). Conclusions: To our knowledge, this is the first study that attempts to correlate lung dose and 4DCT ventilation-based function to thoracic toxicity after radiation therapy. Although the results were not significant at the .05 level, our data suggests

  11. Smoking-related interstitial fibrosis combined with pulmonary emphysema: computed tomography-pathologic correlative study using lobectomy specimens.

    Science.gov (United States)

    Otani, Hideji; Tanaka, Tomonori; Murata, Kiyoshi; Fukuoka, Junya; Nitta, Norihisa; Nagatani, Yukihiro; Sonoda, Akinaga; Takahashi, Masashi

    2016-01-01

    To evaluate the incidence and pathologic correlation of thin-section computed tomography (TSCT) findings in smoking-related interstitial fibrosis (SRIF) with pulmonary emphysema. Our study included 172 consecutive patients who underwent TSCT and subsequent lobectomy. TSCT findings including clustered cysts with visible walls (CCVW) and ground-glass attenuation with/without reticulation (GGAR) were evaluated and compared in nonsmokers and smokers and among lung locations. TSCT findings, especially CCVW, were also compared with histological findings using lobectomy specimens. The incidence of CCVW and GGAR was significantly higher in smokers than in nonsmokers (34.1% and 40.7%, respectively, vs 2.0% and 12.2%). CCVW and GGAR were frequently found in the lower and peripheral zones. Histologically, CCVW corresponded more often with SRIF with emphysema than usual interstitial pneumonia (UIP, 63.3% vs 30%). CCVW of irregular size and shape were seen in 19 of 20 SRIF with emphysema and in seven of nine UIP-manifested areas with similar round cysts. A less-involved subpleural parenchyma was observed more frequently in SRIF with emphysema. SRIF with emphysema is a more frequent pathological finding than UIP in patients with CCVW on TSCT. The irregular size and shape of CCVW and a less-involved subpleural parenchyma may be a clue suggesting the presence of SRIF with emphysema.

  12. Sequence detection analysis based on canonical correlation for steady-state visual evoked potential brain computer interfaces.

    Science.gov (United States)

    Cao, Lei; Ju, Zhengyu; Li, Jie; Jian, Rongjun; Jiang, Changjun

    2015-09-30

    Steady-state visual evoked potential (SSVEP) has been widely applied to develop brain computer interface (BCI) systems. The essence of SSVEP recognition is to recognize the frequency component of target stimulus focused by a subject significantly present in EEG spectrum. In this paper, a novel statistical approach based on sequence detection (SD) is proposed for improving the performance of SSVEP recognition. This method uses canonical correlation analysis (CCA) coefficients to observe SSVEP signal sequence. And then, a threshold strategy is utilized for SSVEP recognition. The result showed the classification performance with the longer duration of time window achieved the higher accuracy for most subjects. And the average time costing per trial was lower than the predefined recognition time. It was implicated that our approach could improve the speed of BCI system in contrast to other methods. Comparison with existing method(s): In comparison with other resultful algorithms, experimental accuracy of SD approach was better than those using a widely used CCA-based method and two newly proposed algorithms, least absolute shrinkage and selection operator (LASSO) recognition model as well as multivariate synchronization index (MSI) method. Furthermore, the information transfer rate (ITR) obtained by SD approach was higher than those using other three methods for most participants. These conclusions demonstrated that our proposed method was promising for a high-speed online BCI. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Efficiency Analysis of the access method with the cascading Bloom filter to the data warehouse on the parallel computing platform

    Science.gov (United States)

    Grigoriev, Yu A.; Proletarskaya, V. A.; Ermakov, E. Yu; Ermakov, O. Yu

    2017-10-01

    A new method was developed with a cascading Bloom filter (CBF) for executing SQL queries in the Apache Spark parallel computing environment. It includes the representation of the original query in the form of several subqueries, the development of a connection graph and the transformation of subqueries, the definition of connections where it is necessary to use Bloom filters, the representation of the graph in terms of Spark. On the example of the query Q3 of the TPC-H test, full-scale experiments were carried out, which confirmed the effectiveness of the developed method.

  14. COMPUTING

    CERN Multimedia

    I. Fisk

    2010-01-01

    Introduction It has been a very active quarter in Computing with interesting progress in all areas. The activity level at the computing facilities, driven by both organised processing from data operations and user analysis, has been steadily increasing. The large-scale production of simulated events that has been progressing throughout the fall is wrapping-up and reprocessing with pile-up will continue. A large reprocessing of all the proton-proton data has just been released and another will follow shortly. The number of analysis jobs by users each day, that was already hitting the computing model expectations at the time of ICHEP, is now 33% higher. We are expecting a busy holiday break to ensure samples are ready in time for the winter conferences. Heavy Ion An activity that is still in progress is computing for the heavy-ion program. The heavy-ion events are collected without zero suppression, so the event size is much large at roughly 11 MB per event of RAW. The central collisions are more complex and...

  15. COMPUTING

    CERN Multimedia

    M. Kasemann P. McBride Edited by M-C. Sawley with contributions from: P. Kreuzer D. Bonacorsi S. Belforte F. Wuerthwein L. Bauerdick K. Lassila-Perini M-C. Sawley

    Introduction More than seventy CMS collaborators attended the Computing and Offline Workshop in San Diego, California, April 20-24th to discuss the state of readiness of software and computing for collisions. Focus and priority were given to preparations for data taking and providing room for ample dialog between groups involved in Commissioning, Data Operations, Analysis and MC Production. Throughout the workshop, aspects of software, operating procedures and issues addressing all parts of the computing model were discussed. Plans for the CMS participation in STEP’09, the combined scale testing for all four experiments due in June 2009, were refined. The article in CMS Times by Frank Wuerthwein gave a good recap of the highly collaborative atmosphere of the workshop. Many thanks to UCSD and to the organizers for taking care of this workshop, which resulted in a long list of action items and was definitely a success. A considerable amount of effort and care is invested in the estimate of the comput...

  16. Electrochemical and computational studies, in protic medium, of Morita-Baylis-Hillman adducts and correlation with leishmanicidal activity

    International Nuclear Information System (INIS)

    Paiva, Yen G. de; Pinho Júnior, Waldomiro; Souza, Antonio A. de; Costa, Cícero O.; Silva, Fábio P.L.; Lima-Junior, Cláudio G.; Vasconcellos, Mario L.A.A.; Goulart, Marília O.F.

    2014-01-01

    Highlights: • Twelve Morita-Baylis-Hillman adducts (MBHA) with significant leishmanicidal activity were studied by electrochemical and computational techniques, in protic media. • Ortho compounds for each series showed more negative reduction potentials than their positional isomers. • Less stable hydroxylamines were formed for ortho derivatives. • There is an inverse correlation between electrochemical parameters and bioactivity. - Abstract: Enzymatic bioreduction of nitro groups plays an important role on the activity of biologically active nitroaromatic compounds. Electrochemical methods are useful tools to simulate in vivo metabolic processes. This work presents electrochemical studies, in protic media (EtOH + phosphate buffer 4:6), using cyclic voltammetry (CV) of twelve Morita-Baylis-Hillman adducts (MBHA) with significant leishmanicidal activity. To facilitate the analysis, the molecules were grouped in four classes according to their side chains. Cyclic voltammograms display, in all cases, only one cathodic wave related to the formation of the correspondent hydroxylamines, which suffer further oxidation generating the nitroso derivatives in a sequential cycle. Ortho compounds exhibit more negative reduction potentials compared to the other isomers, in the same chemical class. This phenomenon could be related not only to structural effects but also to the presence of solvation spheres during the electroreduction process and/or stabilization of the resulting hydroxylamine. A proposal to explain the higher leishmanicidal activity of the ortho compounds compared with the meta and para compounds was suggested based on theoretical calculations (HF/6-31 + G */PCM, water, as a calculation level) that indicated lower thermodynamic stability for the ortho, in comparison to the corresponding meta and para hydroxylamines, fact that may suggest the easier transformation of the electrogenerated compounds into reactive electrophilic intermediates or final products

  17. Axial computed tomography evaluation of the internal nasal valve correlates with clinical valve narrowing and patient complaint.

    Science.gov (United States)

    Moche, Jason A; Cohen, Justin C; Pearlman, Steven J

    2013-07-01

    The objective of this work was to explore the utility of axial computed tomography (CT) imaging to objectively define a narrow internal nasal valve, and compare those findings with clinical examination and patient complaint. Retrospective review from a single facial plastic surgery center. We reviewed 40 consecutive patients evaluated for either sinusitis or nasal airway obstruction for which a CT scan was obtained at a single radiology institution. Thirty-six complete office records were examined for the presence of clinical internal valve narrowing and complaints of nasal obstruction. In total, 72 internal nasal valves were analyzed using axial plane CT and measurements were compared to clinical findings and presence of airway obstruction. Measured valve areas for clinically normal internal nasal valves averaged 0.47 cm(2) vs 0.28 cm(2) for clinically narrow valves, a decrease of 40.4%. In unobstructed nasal airways the valve area averaged 0.51 cm(2) vs 0.38 cm(2) in obstructed airways, a difference of 25.5%. A radiographically measured valve area of <0.30 cm(2) suggests clinical narrowing with a sensitivity of 71.4%, specificity of 88.9%, positive predictive value of 62.5%, and negative predictive value of 92.3%. Using standard axial CT imaging we describe an objective method of radiographically evaluating the nasal valve, demonstrating strong correlation with physical examination and patient complaint. Additionally, radiographic valve areas can be used to screen for clinically narrow nasal valves with good sensitivity and specificity, providing a novel straightforward method for nasal valve assessment. © 2012 ARS-AAOA, LLC.

  18. Energy-angle correlation correction algorithm for monochromatic computed tomography based on Thomson scattering X-ray source

    Science.gov (United States)

    Chi, Zhijun; Du, Yingchao; Huang, Wenhui; Tang, Chuanxiang

    2017-12-01

    The necessity for compact and relatively low cost x-ray sources with monochromaticity, continuous tunability of x-ray energy, high spatial coherence, straightforward polarization control, and high brightness has led to the rapid development of Thomson scattering x-ray sources. To meet the requirement of in-situ monochromatic computed tomography (CT) for large-scale and/or high-attenuation materials based on this type of x-ray source, there is an increasing demand for effective algorithms to correct the energy-angle correlation. In this paper, we take advantage of the parametrization of the x-ray attenuation coefficient to resolve this problem. The linear attenuation coefficient of a material can be decomposed into a linear combination of the energy-dependent photoelectric and Compton cross-sections in the keV energy regime without K-edge discontinuities, and the line integrals of the decomposition coefficients of the above two parts can be determined by performing two spectrally different measurements. After that, the line integral of the linear attenuation coefficient of an imaging object at a certain interested energy can be derived through the above parametrization formula, and monochromatic CT can be reconstructed at this energy using traditional reconstruction methods, e.g., filtered back projection or algebraic reconstruction technique. Not only can monochromatic CT be realized, but also the distributions of the effective atomic number and electron density of the imaging object can be retrieved at the expense of dual-energy CT scan. Simulation results validate our proposal and will be shown in this paper. Our results will further expand the scope of application for Thomson scattering x-ray sources.

  19. Experimental and computational correlation of fracture parameters KIc, JIc, and GIc for unimodular and bimodular graphite components

    Science.gov (United States)

    Bhushan, Awani; Panda, S. K.

    2018-05-01

    The influence of bimodularity (different stress ∼ strain behaviour in tension and compression) on fracture behaviour of graphite specimens has been studied with fracture toughness (KIc), critical J-integral (JIc) and critical strain energy release rate (GIc) as the characterizing parameter. Bimodularity index (ratio of tensile Young's modulus to compression Young's modulus) of graphite specimens has been obtained from the normalized test data of tensile and compression experimentation. Single edge notch bend (SENB) testing of pre-cracked specimens from the same lot have been carried out as per ASTM standard D7779-11 to determine the peak load and critical fracture parameters KIc, GIc and JIc using digital image correlation technology of crack opening displacements. Weibull weakest link theory has been used to evaluate the mean peak load, Weibull modulus and goodness of fit employing two parameter least square method (LIN2), biased (MLE2-B) and unbiased (MLE2-U) maximum likelihood estimator. The stress dependent elasticity problem of three-dimensional crack progression behaviour for the bimodular graphite components has been solved as an iterative finite element procedure. The crack characterizing parameters critical stress intensity factor and critical strain energy release rate have been estimated with the help of Weibull distribution plot between peak loads versus cumulative probability of failure. Experimental and Computational fracture parameters have been compared qualitatively to describe the significance of bimodularity. The bimodular influence on fracture behaviour of SENB graphite has been reflected on the experimental evaluation of GIc values only, which has been found to be different from the calculated JIc values. Numerical evaluation of bimodular 3D J-integral value is found to be close to the GIc value whereas the unimodular 3D J-value is nearer to the JIc value. The significant difference between the unimodular JIc and bimodular GIc indicates that

  20. Improving the accessibility at home: implementation of a domotic application using a p300-based brain computer interface system

    Directory of Open Access Journals (Sweden)

    Rebeca Corralejo Palacios

    2012-05-01

    Full Text Available The aim of this study was to develop a Brain Computer Interface (BCI application to control domotic devices usually present at home. Previous studies have shown that people with severe disabilities, both physical and cognitive ones, do not achieve high accuracy results using motor imagery-based BCIs. To overcome this limitation, we propose the implementation of a BCI application using P300 evoked potentials, because neither extensive training nor extremely high concentration level are required for this kind of BCIs. The implemented BCI application allows to control several devices as TV, DVD player, mini Hi-Fi system, multimedia hard drive, telephone, heater, fan and lights. Our aim is that potential users, i.e. people with severe disabilities, are able to achieve high accuracy. Therefore, this domotic BCI application is useful to increase

  1. Inverse correlation between reactive oxygen species in unwashed semen and sperm motion parameters as measured by a computer-assisted semen analyzer.

    Science.gov (United States)

    Takeshima, Teppei; Yumura, Yasushi; Yasuda, Kengo; Sanjo, Hiroyuki; Kuroda, Shinnosuke; Yamanaka, Hiroyuki; Iwasaki, Akira

    2017-01-01

    This study investigated the correlation between sperm motion parameters obtained by a computer-assisted semen analyzer and levels of reactive oxygen species in unwashed semen. In total, 847 patients, except for azoospermic patients were investigated. At the time of each patient's first consultation, semen parameters were measured using SMAS™ or CellSoft 3000™, and production of reactive oxygen species was measured using a computer-driven LKB Wallac Luminometer 1251 Analyzer. The patients were divided into two groups: reactive oxygen species - positive and negative. The semen parameters within each group were measured using one of the two computer-assisted semen analyzer systems and then compared. Correlations between reactive oxygen species levels and sperm motion parameters in semen from the reactive oxygen species - positive group were also investigated. Reactive oxygen species were detected in semen samples of 282 cases (33.3%). Sperm concentration (P semen damage sperm concentration, motility, and other sperm motion parameters.

  2. COMPUTING

    CERN Multimedia

    P. McBride

    It has been a very active year for the computing project with strong contributions from members of the global community. The project has focused on site preparation and Monte Carlo production. The operations group has begun processing data from P5 as part of the global data commissioning. Improvements in transfer rates and site availability have been seen as computing sites across the globe prepare for large scale production and analysis as part of CSA07. Preparations for the upcoming Computing Software and Analysis Challenge CSA07 are progressing. Ian Fisk and Neil Geddes have been appointed as coordinators for the challenge. CSA07 will include production tests of the Tier-0 production system, reprocessing at the Tier-1 sites and Monte Carlo production at the Tier-2 sites. At the same time there will be a large analysis exercise at the Tier-2 centres. Pre-production simulation of the Monte Carlo events for the challenge is beginning. Scale tests of the Tier-0 will begin in mid-July and the challenge it...

  3. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction It has been a very active quarter in Computing with interesting progress in all areas. The activity level at the computing facilities, driven by both organised processing from data operations and user analysis, has been steadily increasing. The large-scale production of simulated events that has been progressing throughout the fall is wrapping-up and reprocessing with pile-up will continue. A large reprocessing of all the proton-proton data has just been released and another will follow shortly. The number of analysis jobs by users each day, that was already hitting the computing model expectations at the time of ICHEP, is now 33% higher. We are expecting a busy holiday break to ensure samples are ready in time for the winter conferences. Heavy Ion The Tier 0 infrastructure was able to repack and promptly reconstruct heavy-ion collision data. Two copies were made of the data at CERN using a large CASTOR disk pool, and the core physics sample was replicated ...

  4. COMPUTING

    CERN Multimedia

    I. Fisk

    2012-01-01

    Introduction Computing continued with a high level of activity over the winter in preparation for conferences and the start of the 2012 run. 2012 brings new challenges with a new energy, more complex events, and the need to make the best use of the available time before the Long Shutdown. We expect to be resource constrained on all tiers of the computing system in 2012 and are working to ensure the high-priority goals of CMS are not impacted. Heavy ions After a successful 2011 heavy-ion run, the programme is moving to analysis. During the run, the CAF resources were well used for prompt analysis. Since then in 2012 on average 200 job slots have been used continuously at Vanderbilt for analysis workflows. Operations Office As of 2012, the Computing Project emphasis has moved from commissioning to operation of the various systems. This is reflected in the new organisation structure where the Facilities and Data Operations tasks have been merged into a common Operations Office, which now covers everything ...

  5. COMPUTING

    CERN Multimedia

    M. Kasemann

    CCRC’08 challenges and CSA08 During the February campaign of the Common Computing readiness challenges (CCRC’08), the CMS computing team had achieved very good results. The link between the detector site and the Tier0 was tested by gradually increasing the number of parallel transfer streams well beyond the target. Tests covered the global robustness at the Tier0, processing a massive number of very large files and with a high writing speed to tapes.  Other tests covered the links between the different Tiers of the distributed infrastructure and the pre-staging and reprocessing capacity of the Tier1’s: response time, data transfer rate and success rate for Tape to Buffer staging of files kept exclusively on Tape were measured. In all cases, coordination with the sites was efficient and no serious problem was found. These successful preparations prepared the ground for the second phase of the CCRC’08 campaign, in May. The Computing Software and Analysis challen...

  6. COMPUTING

    CERN Multimedia

    I. Fisk

    2010-01-01

    Introduction The first data taking period of November produced a first scientific paper, and this is a very satisfactory step for Computing. It also gave the invaluable opportunity to learn and debrief from this first, intense period, and make the necessary adaptations. The alarm procedures between different groups (DAQ, Physics, T0 processing, Alignment/calibration, T1 and T2 communications) have been reinforced. A major effort has also been invested into remodeling and optimizing operator tasks in all activities in Computing, in parallel with the recruitment of new Cat A operators. The teams are being completed and by mid year the new tasks will have been assigned. CRB (Computing Resource Board) The Board met twice since last CMS week. In December it reviewed the experience of the November data-taking period and could measure the positive improvements made for the site readiness. It also reviewed the policy under which Tier-2 are associated with Physics Groups. Such associations are decided twice per ye...

  7. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction More than seventy CMS collaborators attended the Computing and Offline Workshop in San Diego, California, April 20-24th to discuss the state of readiness of software and computing for collisions. Focus and priority were given to preparations for data taking and providing room for ample dialog between groups involved in Commissioning, Data Operations, Analysis and MC Production. Throughout the workshop, aspects of software, operating procedures and issues addressing all parts of the computing model were discussed. Plans for the CMS participation in STEP’09, the combined scale testing for all four experiments due in June 2009, were refined. The article in CMS Times by Frank Wuerthwein gave a good recap of the highly collaborative atmosphere of the workshop. Many thanks to UCSD and to the organizers for taking care of this workshop, which resulted in a long list of action items and was definitely a success. A considerable amount of effort and care is invested in the estimate of the co...

  8. Fluorescence-Guided Probes of Aptamer-Targeted Gold Nanoparticles with Computed Tomography Imaging Accesses for in Vivo Tumor Resection.

    Science.gov (United States)

    Li, Cheng-Hung; Kuo, Tsung-Rong; Su, Hsin-Jan; Lai, Wei-Yun; Yang, Pan-Chyr; Chen, Jinn-Shiun; Wang, Di-Yan; Wu, Yi-Chun; Chen, Chia-Chun

    2015-10-28

    Recent development of molecular imaging probes for fluorescence-guided surgery has shown great progresses for determining tumor margin to execute the tissue resection. Here we synthesize the fluorescent gold nanoparticles conjugated with diatrizoic acid and nucleolin-targeted AS1411 aptamer. The nanoparticle conjugates exhibit high water-solubility, good biocompatibility, visible fluorescence and strong X-ray attenuation for computed tomography (CT) contrast enhancement. The fluorescent nanoparticle conjugates are applied as a molecular contrast agent to reveal the tumor location in CL1-5 tumor-bearing mice by CT imaging. Furthermore, the orange-red fluorescence emitting from the conjugates in the CL1-5 tumor can be easily visualized by the naked eyes. After the resection, the IVIS measurements show that the fluorescence signal of the nanoparticle conjugates in the tumor is greatly enhanced in comparison to that in the controlled experiment. Our work has shown potential application of functionalized nanoparticles as a dual-function imaging agent in clinical fluorescence-guided surgery.

  9. Use of computer access technology as an alternative to writing for a pre-school child with athetoid cerebral palsy--a case report.

    Science.gov (United States)

    Dhas, Brightlin Nithis; Samuel, Preethy Sarah; Manigandan, C

    2014-07-01

    The purpose of this study was to demonstrate the use of an outcome-driven model of decision-making in the implementation of computer access technology (CAT) for a pre-school child with athetoid cerebral palsy. The child did not have the fine motor skills required to hold a pencil but had the cognitive abilities to learn to write; therefore, we explored the use of a CAT device to enable written communication. Case study methodology was used to describe the selection process, child-level outcomes, and clinical challenges faced by the therapist in the use of a consortium model that was designed for an outcome-driven model of decision-making. The critical role of an occupational therapist in this process using a family-centered approach is discussed.

  10. COMPUTING

    CERN Multimedia

    2010-01-01

    Introduction Just two months after the “LHC First Physics” event of 30th March, the analysis of the O(200) million 7 TeV collision events in CMS accumulated during the first 60 days is well under way. The consistency of the CMS computing model has been confirmed during these first weeks of data taking. This model is based on a hierarchy of use-cases deployed between the different tiers and, in particular, the distribution of RECO data to T1s, who then serve data on request to T2s, along a topology known as “fat tree”. Indeed, during this period this model was further extended by almost full “mesh” commissioning, meaning that RECO data were shipped to T2s whenever possible, enabling additional physics analyses compared with the “fat tree” model. Computing activities at the CMS Analysis Facility (CAF) have been marked by a good time response for a load almost evenly shared between ALCA (Alignment and Calibration tasks - highest p...

  11. COMPUTING

    CERN Multimedia

    Contributions from I. Fisk

    2012-01-01

    Introduction The start of the 2012 run has been busy for Computing. We have reconstructed, archived, and served a larger sample of new data than in 2011, and we are in the process of producing an even larger new sample of simulations at 8 TeV. The running conditions and system performance are largely what was anticipated in the plan, thanks to the hard work and preparation of many people. Heavy ions Heavy Ions has been actively analysing data and preparing for conferences.  Operations Office Figure 6: Transfers from all sites in the last 90 days For ICHEP and the Upgrade efforts, we needed to produce and process record amounts of MC samples while supporting the very successful data-taking. This was a large burden, especially on the team members. Nevertheless the last three months were very successful and the total output was phenomenal, thanks to our dedicated site admins who keep the sites operational and the computing project members who spend countless hours nursing the...

  12. COMPUTING

    CERN Multimedia

    Matthias Kasemann

    Overview The main focus during the summer was to handle data coming from the detector and to perform Monte Carlo production. The lessons learned during the CCRC and CSA08 challenges in May were addressed by dedicated PADA campaigns lead by the Integration team. Big improvements were achieved in the stability and reliability of the CMS Tier1 and Tier2 centres by regular and systematic follow-up of faults and errors with the help of the Savannah bug tracking system. In preparation for data taking the roles of a Computing Run Coordinator and regular computing shifts monitoring the services and infrastructure as well as interfacing to the data operations tasks are being defined. The shift plan until the end of 2008 is being put together. User support worked on documentation and organized several training sessions. The ECoM task force delivered the report on “Use Cases for Start-up of pp Data-Taking” with recommendations and a set of tests to be performed for trigger rates much higher than the ...

  13. COMPUTING

    CERN Multimedia

    P. MacBride

    The Computing Software and Analysis Challenge CSA07 has been the main focus of the Computing Project for the past few months. Activities began over the summer with the preparation of the Monte Carlo data sets for the challenge and tests of the new production system at the Tier-0 at CERN. The pre-challenge Monte Carlo production was done in several steps: physics generation, detector simulation, digitization, conversion to RAW format and the samples were run through the High Level Trigger (HLT). The data was then merged into three "Soups": Chowder (ALPGEN), Stew (Filtered Pythia) and Gumbo (Pythia). The challenge officially started when the first Chowder events were reconstructed on the Tier-0 on October 3rd. The data operations teams were very busy during the the challenge period. The MC production teams continued with signal production and processing while the Tier-0 and Tier-1 teams worked on splitting the Soups into Primary Data Sets (PDS), reconstruction and skimming. The storage sys...

  14. Correlated responses in tissue weights measured in vivo by computer tomography in Dorset Down sheep selected for lean tissue growth

    International Nuclear Information System (INIS)

    Nsoso, S.J.; Young, M.J.; Beatson, P.R.

    2003-01-01

    The aim of this study was to estimate correlated responses in lean, fat and bone weights in vivo in Dorset Down sheep selected for lean tissue growth. Over the period 1986-1992 inclusive, the lean tissue growth line had been selected using two economic indices for an increased aggregate breeding value incorporating predicted lean and fat weights with positive and negative economic weightings, respectively. The control line was selected for no change in lean tissue growth each year. Animals were born and run on pasture all year round. X-ray computer tomography was used to estimate the weights of lean, fat and bone in vivo in the 1994-born sheep, aged 265-274 days and selected randomly into 12 rams and 12 ewes from the selected line and 10 rams and 9 ewes from the control line. The lean tissue growth line had significantly greater responses in lean weight (+0.65 + 0.10 kg) and lean percentage (+1.19 + 0.17%) and significantly lesser fat weight (-0.36 + 0.08 kg) and fat percentage (-1.88 + 0.20%) compared to the control line. There was a significant increase in bone weight (+0.27 + 0.03 kg) and bone percentage (+0.69 + 0.09%) in the lean tissue growth line compared to the control line. Responses differed significantly between sexes of the lean tissue growth line, rams having a greater response in weight of lean (+1.22 + 0.20 vs. +0.08 + 0.22 kg) and bone (+0.45 + 0.06 vs. +0.09 + 0.07 kg), and a lesser response in weight of fat (-0.03 + 0.15 vs. -0.70 + 0.16 kg) than the ewes. Selection led to significant changes in lean (increase) and fat weights (decrease), and bone weight increased. Although responses in the lean tissue growth line differed significantly between sexes, there were confounding factors due to differences in management and lack of comparison at equal stage of development. Therefore, to assess real genetic differences further studies should be conducted taking these factors into consideration

  15. Heat transfer, velocity-temperature correlation, and turbulent shear stress from Navier-Stokes computations of shock wave/turbulent boundary layer interaction flows

    Science.gov (United States)

    Wang, C. R.; Hingst, W. R.; Porro, A. R.

    1991-01-01

    The properties of 2-D shock wave/turbulent boundary layer interaction flows were calculated by using a compressible turbulent Navier-Stokes numerical computational code. Interaction flows caused by oblique shock wave impingement on the turbulent boundary layer flow were considered. The oblique shock waves were induced with shock generators at angles of attack less than 10 degs in supersonic flows. The surface temperatures were kept at near-adiabatic (ratio of wall static temperature to free stream total temperature) and cold wall (ratio of wall static temperature to free stream total temperature) conditions. The computational results were studied for the surface heat transfer, velocity temperature correlation, and turbulent shear stress in the interaction flow fields. Comparisons of the computational results with existing measurements indicated that (1) the surface heat transfer rates and surface pressures could be correlated with Holden's relationship, (2) the mean flow streamwise velocity components and static temperatures could be correlated with Crocco's relationship if flow separation did not occur, and (3) the Baldwin-Lomax turbulence model should be modified for turbulent shear stress computations in the interaction flows.

  16. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction The Computing Team successfully completed the storage, initial processing, and distribution for analysis of proton-proton data in 2011. There are still a variety of activities ongoing to support winter conference activities and preparations for 2012. Heavy ions The heavy-ion run for 2011 started in early November and has already demonstrated good machine performance and success of some of the more advanced workflows planned for 2011. Data collection will continue until early December. Facilities and Infrastructure Operations Operational and deployment support for WMAgent and WorkQueue+Request Manager components, routinely used in production by Data Operations, are provided. The GlideInWMS and components installation are now deployed at CERN, which is added to the GlideInWMS factory placed in the US. There has been new operational collaboration between the CERN team and the UCSD GlideIn factory operators, covering each others time zones by monitoring/debugging pilot jobs sent from the facto...

  17. Fast-GPU-PCC: A GPU-Based Technique to Compute Pairwise Pearson's Correlation Coefficients for Time Series Data-fMRI Study.

    Science.gov (United States)

    Eslami, Taban; Saeed, Fahad

    2018-04-20

    Functional magnetic resonance imaging (fMRI) is a non-invasive brain imaging technique, which has been regularly used for studying brain’s functional activities in the past few years. A very well-used measure for capturing functional associations in brain is Pearson’s correlation coefficient. Pearson’s correlation is widely used for constructing functional network and studying dynamic functional connectivity of the brain. These are useful measures for understanding the effects of brain disorders on connectivities among brain regions. The fMRI scanners produce huge number of voxels and using traditional central processing unit (CPU)-based techniques for computing pairwise correlations is very time consuming especially when large number of subjects are being studied. In this paper, we propose a graphics processing unit (GPU)-based algorithm called Fast-GPU-PCC for computing pairwise Pearson’s correlation coefficient. Based on the symmetric property of Pearson’s correlation, this approach returns N ( N − 1 ) / 2 correlation coefficients located at strictly upper triangle part of the correlation matrix. Storing correlations in a one-dimensional array with the order as proposed in this paper is useful for further usage. Our experiments on real and synthetic fMRI data for different number of voxels and varying length of time series show that the proposed approach outperformed state of the art GPU-based techniques as well as the sequential CPU-based versions. We show that Fast-GPU-PCC runs 62 times faster than CPU-based version and about 2 to 3 times faster than two other state of the art GPU-based methods.

  18. Individual and family environmental correlates of television and computer time in 10- to 12-year-old European children: the ENERGY-project.

    Science.gov (United States)

    Verloigne, Maïté; Van Lippevelde, Wendy; Bere, Elling; Manios, Yannis; Kovács, Éva; Grillenberger, Monika; Maes, Lea; Brug, Johannes; De Bourdeaudhuij, Ilse

    2015-09-18

    The aim was to investigate which individual and family environmental factors are related to television and computer time separately in 10- to-12-year-old children within and across five European countries (Belgium, Germany, Greece, Hungary, Norway). Data were used from the ENERGY-project. Children and one of their parents completed a questionnaire, including questions on screen time behaviours and related individual and family environmental factors. Family environmental factors included social, political, economic and physical environmental factors. Complete data were obtained from 2022 child-parent dyads (53.8 % girls, mean child age 11.2 ± 0.8 years; mean parental age 40.5 ± 5.1 years). To examine the association between individual and family environmental factors (i.e. independent variables) and television/computer time (i.e. dependent variables) in each country, multilevel regression analyses were performed using MLwiN 2.22, adjusting for children's sex and age. In all countries, children reported more television and/or computer time, if children and their parents thought that the maximum recommended level for watching television and/or using the computer was higher and if children had a higher preference for television watching and/or computer use and a lower self-efficacy to control television watching and/or computer use. Most physical and economic environmental variables were not significantly associated with television or computer time. Slightly more individual factors were related to children's computer time and more parental social environmental factors to children's television time. We also found different correlates across countries: parental co-participation in television watching was significantly positively associated with children's television time in all countries, except for Greece. A higher level of parental television and computer time was only associated with a higher level of children's television and computer time in Hungary. Having rules

  19. COMPUTING

    CERN Multimedia

    M. Kasemann

    CMS relies on a well functioning, distributed computing infrastructure. The Site Availability Monitoring (SAM) and the Job Robot submission have been very instrumental for site commissioning in order to increase availability of more sites such that they are available to participate in CSA07 and are ready to be used for analysis. The commissioning process has been further developed, including "lessons learned" documentation via the CMS twiki. Recently the visualization, presentation and summarizing of SAM tests for sites has been redesigned, it is now developed by the central ARDA project of WLCG. Work to test the new gLite Workload Management System was performed; a 4 times increase in throughput with respect to LCG Resource Broker is observed. CMS has designed and launched a new-generation traffic load generator called "LoadTest" to commission and to keep exercised all data transfer routes in the CMS PhE-DEx topology. Since mid-February, a transfer volume of about 12 P...

  20. Paracoccidioidomycosis: high-resolution computed tomography - anatomo-pathological correlation; Paracoccidioidomicose: correlacao da tomografia computadorizada de alta resolucao com a anatomopatologia

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson; Muniz, Maria Angelica Soares; Santos, Maria Lucia de Oliveira [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Radiologia; Moraes, Heleno Pinto de [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Patologia; Capone, Domenico [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Pneumologia

    2000-12-01

    We reviewed the high-resolution computed tomography scans of 13 patients with paracoccidioidomycosis and correlated the findings with the anatomo-pathological findings of 5 patients. The most frequent findings observed were thickening of the interlobular septa, emphysema, ground glass areas, thickening of bronchial walls, tracheal dilatation, nodules, cavities and evidence of fibrosing disease such as architectural distortion, parenchymatous bands, spicular pleural thickening, intralobular reticulate and thickening with distortion off the axial interstitium. (author)

  1. Computational nanometrology of line-edge roughness: noise effects, cross-line correlations and the role of etch transfer

    Science.gov (United States)

    Constantoudis, Vassilios; Papavieros, George; Lorusso, Gian; Rutigliani, Vito; Van Roey, Frieda; Gogolides, Evangelos

    2018-03-01

    The aim of this paper is to investigate the role of etch transfer in two challenges of LER metrology raised by recent evolutions in lithography: the effects of SEM noise and the cross-line and edge correlations. The first comes from the ongoing scaling down of linewidths, which dictates SEM imaging with less scanning frames to reduce specimen damage and hence with more noise. During the last decade, it has been shown that image noise can be an important budget of the measured LER while systematically affects and alter the PSD curve of LER at high frequencies. A recent method for unbiased LER measurement is based on the systematic Fourier or correlation analysis to decompose the effects of noise from true LER (Fourier-Correlation filtering method). The success of the method depends on the PSD and HHCF curve. Previous experimental and model works have revealed that etch transfer affects the PSD of LER reducing its high frequency values. In this work, we estimate the noise contribution to the biased LER through PSD flat floor at high frequencies and relate it with the differences between the PSDs of lithography and etched LER. Based on this comparison, we propose an improvement of the PSD/HHCF-based method for noise-free LER measurement to include the missed high frequency real LER. The second issue is related with the increased density of lithographic patterns and the special characteristics of DSA and MP lithography patterns exhibits. In a previous work, we presented an enlarged LER characterization methodology for such patterns, which includes updated versions of the old metrics along with new metrics defined and developed to capture cross-edge and cross-line correlations. The fundamental concept has been the Line Center Roughness (LCR), the edge c-factor and the line c-factor correlation function and length quantifying the line fluctuations and the extent of cross-edge and cross-line correlations. In this work, we focus on the role of etch steps on cross-edge and

  2. Basic Technology Competencies, Attitude towards Computer Assisted Education and Usage of Technologies in Turkish Lesson: A Correlation

    Science.gov (United States)

    Özdemir, Serpil

    2017-01-01

    The present research was done to determine the basic technology competency of Turkish teachers, their attitude towards computer-assisted education, and their technology operation level in Turkish lessons, and to designate the relationship between them. 85 Turkish teachers studying in public schools in Bartin participated in the research. The…

  3. Analysis of multiuser mixed RF/FSO relay networks for performance improvements in Cloud Computing-Based Radio Access Networks (CC-RANs)

    Science.gov (United States)

    Alimi, Isiaka A.; Monteiro, Paulo P.; Teixeira, António L.

    2017-11-01

    The key paths toward the fifth generation (5G) network requirements are towards centralized processing and small-cell densification systems that are implemented on the cloud computing-based radio access networks (CC-RANs). The increasing recognitions of the CC-RANs can be attributed to their valuable features regarding system performance optimization and cost-effectiveness. Nevertheless, realization of the stringent requirements of the fronthaul that connects the network elements is highly demanding. In this paper, considering the small-cell network architectures, we present multiuser mixed radio-frequency/free-space optical (RF/FSO) relay networks as feasible technologies for the alleviation of the stringent requirements in the CC-RANs. In this study, we use the end-to-end (e2e) outage probability, average symbol error probability (ASEP), and ergodic channel capacity as the performance metrics in our analysis. Simulation results show the suitability of deployment of mixed RF/FSO schemes in the real-life scenarios.

  4. Joint image reconstruction method with correlative multi-channel prior for x-ray spectral computed tomography

    Science.gov (United States)

    Kazantsev, Daniil; Jørgensen, Jakob S.; Andersen, Martin S.; Lionheart, William R. B.; Lee, Peter D.; Withers, Philip J.

    2018-06-01

    Rapid developments in photon-counting and energy-discriminating detectors have the potential to provide an additional spectral dimension to conventional x-ray grayscale imaging. Reconstructed spectroscopic tomographic data can be used to distinguish individual materials by characteristic absorption peaks. The acquired energy-binned data, however, suffer from low signal-to-noise ratio, acquisition artifacts, and frequently angular undersampled conditions. New regularized iterative reconstruction methods have the potential to produce higher quality images and since energy channels are mutually correlated it can be advantageous to exploit this additional knowledge. In this paper, we propose a novel method which jointly reconstructs all energy channels while imposing a strong structural correlation. The core of the proposed algorithm is to employ a variational framework of parallel level sets to encourage joint smoothing directions. In particular, the method selects reference channels from which to propagate structure in an adaptive and stochastic way while preferring channels with a high data signal-to-noise ratio. The method is compared with current state-of-the-art multi-channel reconstruction techniques including channel-wise total variation and correlative total nuclear variation regularization. Realistic simulation experiments demonstrate the performance improvements achievable by using correlative regularization methods.

  5. Morphological measurements in computed tomography correlate with airflow obstruction in chronic obstructive pulmonary disease : systematic review and meta-analysis

    NARCIS (Netherlands)

    Xie, X.Q.; de Jong, P.A.; Oudkerk, M.; Wang, Y.; ten Hacken, N.H.T.; Miao, J.T.; Zhang, GuiXiang; de Bock, G.H.; Vliegenthart, R.

    2012-01-01

    To determine the correlation between CT measurements of emphysema or peripheral airways and airflow obstruction in chronic obstructive pulmonary disease (COPD). PubMed, Embase and Web of Knowledge were searched from 1976 to 2011. Two reviewers independently screened 1,763 citations to identify

  6. Correlation between the signal-to-noise ratio improvement factor (KSNR) and clinical image quality for chest imaging with a computed radiography system

    International Nuclear Information System (INIS)

    Moore, C S; Wood, T J; Saunderson, J R; Beavis, A W

    2015-01-01

    This work assessed the appropriateness of the signal-to-noise ratio improvement factor (K SNR ) as a metric for the optimisation of computed radiography (CR) of the chest. The results of a previous study in which four experienced image evaluators graded computer simulated chest images using a visual grading analysis scoring (VGAS) scheme to quantify the benefit of using an anti-scatter grid were used for the clinical image quality measurement (number of simulated patients  =  80). The K SNR was used to calculate the improvement in physical image quality measured in a physical chest phantom. K SNR correlation with VGAS was assessed as a function of chest region (lung, spine and diaphragm/retrodiaphragm), and as a function of x-ray tube voltage in a given chest region. The correlation of the latter was determined by the Pearson correlation coefficient. VGAS and K SNR image quality metrics demonstrated no correlation in the lung region but did show correlation in the spine and diaphragm/retrodiaphragmatic regions. However, there was no correlation as a function of tube voltage in any region; a Pearson correlation coefficient (R) of  −0.93 (p  =  0.015) was found for lung, a coefficient (R) of  −0.95 (p  =  0.46) was found for spine, and a coefficient (R) of  −0.85 (p  =  0.015) was found for diaphragm. All demonstrate strong negative correlations indicating conflicting results, i.e. K SNR increases with tube voltage but VGAS decreases. Medical physicists should use the K SNR metric with caution when assessing any potential improvement in clinical chest image quality when introducing an anti-scatter grid for CR imaging, especially in the lung region. This metric may also be a limited descriptor of clinical chest image quality as a function of tube voltage when a grid is used routinely. (paper)

  7. Quantitative computed tomography analysis of the airways in patients with cystic fibrosis using automated software: correlation with spirometry in the evaluation of severity

    International Nuclear Information System (INIS)

    Santos, Marcel Koenigkam; Cruvinel, Danilo Lemos; Menezes, Marcelo Bezerra de; Teixeira, Sara Reis; Vianna, Elcio de Oliveira; Elias Junior, Jorge; Martinez, Jose Antonio Baddini

    2016-01-01

    Objective: To perform a quantitative analysis of the airways using automated software, in computed tomography images of patients with cystic fibrosis, correlating the results with spirometric findings. Materials and methods: Thirty-four patients with cystic fibrosis were studied-20 males and 14 females; mean age 18 ± 9 years - divided into two groups according to the spirometry findings: group I (n = 21), without severe airflow obstruction (forced expiratory volume in first second [FEV1] > 50% predicted), and group II (n = 13), with severe obstruction (FEV1 ≤ 50% predicted). The following tracheobronchial tree parameters were obtained automatically: bronchial diameter, area, thickness, and wall attenuation. Results: On average, 52 bronchi per patient were studied. The number of bronchi analyzed was higher in group II. The correlation with spirometry findings, especially between the relative wall thickness of third to eighth bronchial generation and predicted FEV1, was better in group I. Conclusion: Quantitative analysis of the airways by computed tomography can be useful for assessing disease severity in cystic fibrosis patients. In patients with severe airflow obstruction, the number of bronchi studied by the method is higher, indicating more bronchiectasis. In patients without severe obstruction, the relative bronchial wall thickness showed a good correlation with the predicted FEV1. (author)

  8. Quantitative computed tomography analysis of the airways in patients with cystic fibrosis using automated software: correlation with spirometry in the evaluation of severity

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Marcel Koenigkam; Cruvinel, Danilo Lemos; Menezes, Marcelo Bezerra de; Teixeira, Sara Reis; Vianna, Elcio de Oliveira; Elias Junior, Jorge; Martinez, Jose Antonio Baddini, E-mail: marcelk46@yahoo.com.br [Universidade de Sao Paulo (HC/FMRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina

    2016-11-15

    Objective: To perform a quantitative analysis of the airways using automated software, in computed tomography images of patients with cystic fibrosis, correlating the results with spirometric findings. Materials and methods: Thirty-four patients with cystic fibrosis were studied-20 males and 14 females; mean age 18 ± 9 years - divided into two groups according to the spirometry findings: group I (n = 21), without severe airflow obstruction (forced expiratory volume in first second [FEV1] > 50% predicted), and group II (n = 13), with severe obstruction (FEV1 ≤ 50% predicted). The following tracheobronchial tree parameters were obtained automatically: bronchial diameter, area, thickness, and wall attenuation. Results: On average, 52 bronchi per patient were studied. The number of bronchi analyzed was higher in group II. The correlation with spirometry findings, especially between the relative wall thickness of third to eighth bronchial generation and predicted FEV1, was better in group I. Conclusion: Quantitative analysis of the airways by computed tomography can be useful for assessing disease severity in cystic fibrosis patients. In patients with severe airflow obstruction, the number of bronchi studied by the method is higher, indicating more bronchiectasis. In patients without severe obstruction, the relative bronchial wall thickness showed a good correlation with the predicted FEV1. (author)

  9. Food Access and Perceptions of the Community and Household Food Environment as Correlates of Fruit and Vegetable Intake among Rural Seniors

    Directory of Open Access Journals (Sweden)

    Johnson Cassandra M

    2010-06-01

    Full Text Available Abstract Background Although the importance of fruit and vegetable consumption to health has been well established, few studies have focused on access to fruits and vegetables in rural areas; even fewer examined the relationship between food access and fruit and vegetable consumption among seniors. Methods To examine the spatial challenges to good nutrition faced by seniors who reside in rural areas and how spatial access influences fruit and vegetable intake. A cross-sectional analysis using data from the 2006 Brazos Valley Health Assessment (mailsurvey for 582 rural seniors (60-90 years, who were recruited by random digit dialing; food store data from the 2006-2007 Brazos Valley Food Environment Project that used ground-truthed methods to identify, geocode, and inventory fruit and vegetables in all food stores. Results Few of the BVHA seniors consumed the recommended intakes of fruits or vegetables; women consumed more servings of fruit (1.49 ± 0.05 vs. 1.29 ± 0.07, p = 0.02, similar servings of vegetables (2.18 ± 0.04 vs. 2.09 ± 0.07, p = 0.28, and more combined fruit and vegetables (3.67 ± 0.08 vs. 3.38 ± 0.12, p = 0.04 than men. The median distances to fresh fruit and vegetables were 5.5 miles and 6.4 miles, respectively. When canned and frozen fruit and vegetables were included in the measurement of overall fruit or vegetables, the median distance for a good selection of fruit or vegetables decreased to 3.4 miles for overall fruit and 3.2 miles for overall vegetables. Almost 14% reported that food supplies did not last and there was not enough money to buy more. Our analyses revealed that objective and perceived measures of food store access - increased distance to the nearest supermarket, food store with a good variety of fresh and processed fruit, or food store with a good variety of fresh and processed vegetables - were associated with decreased daily consumption of fruit, vegetables, and combined fruit and vegetables, after

  10. Food access and perceptions of the community and household food environment as correlates of fruit and vegetable intake among rural seniors.

    Science.gov (United States)

    Sharkey, Joseph R; Johnson, Cassandra M; Dean, Wesley R

    2010-06-02

    Although the importance of fruit and vegetable consumption to health has been well established, few studies have focused on access to fruits and vegetables in rural areas; even fewer examined the relationship between food access and fruit and vegetable consumption among seniors. To examine the spatial challenges to good nutrition faced by seniors who reside in rural areas and how spatial access influences fruit and vegetable intake. A cross-sectional analysis using data from the 2006 Brazos Valley Health Assessment (mailsurvey) for 582 rural seniors (60-90 years), who were recruited by random digit dialing; food store data from the 2006-2007 Brazos Valley Food Environment Project that used ground-truthed methods to identify, geocode, and inventory fruit and vegetables in all food stores. Few of the BVHA seniors consumed the recommended intakes of fruits or vegetables; women consumed more servings of fruit (1.49 +/- 0.05 vs. 1.29 +/- 0.07, p = 0.02), similar servings of vegetables (2.18 +/- 0.04 vs. 2.09 +/- 0.07, p = 0.28), and more combined fruit and vegetables (3.67 +/- 0.08 vs. 3.38 +/- 0.12, p = 0.04) than men. The median distances to fresh fruit and vegetables were 5.5 miles and 6.4 miles, respectively. When canned and frozen fruit and vegetables were included in the measurement of overall fruit or vegetables, the median distance for a good selection of fruit or vegetables decreased to 3.4 miles for overall fruit and 3.2 miles for overall vegetables. Almost 14% reported that food supplies did not last and there was not enough money to buy more. Our analyses revealed that objective and perceived measures of food store access--increased distance to the nearest supermarket, food store with a good variety of fresh and processed fruit, or food store with a good variety of fresh and processed vegetables--were associated with decreased daily consumption of fruit, vegetables, and combined fruit and vegetables, after controlling for the influence of individual

  11. Handling of computational in vitro/in vivo correlation problems by Microsoft Excel II. Distribution functions and moments.

    Science.gov (United States)

    Langenbucher, Frieder

    2003-01-01

    MS Excel is a useful tool to handle in vitro/in vivo correlation (IVIVC) distribution functions, with emphasis on the Weibull and the biexponential distribution, which are most useful for the presentation of cumulative profiles, e.g. release in vitro or urinary excretion in vivo, and differential profiles such as the plasma response in vivo. The discussion includes moments (AUC and mean) as summarizing statistics, and data-fitting algorithms for parameter estimation.

  12. Broadband Access

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Broadband Access. Worldwide market for broadband access $30 Billion! Over 200 million broadband subscribers worldwide! Various Competing Broadband access. Digital Subscriber line; Wireless; Optical Fiber.

  13. Three-dimensional biplanar radiography as a new means of accessing femoral version: a comparitive study of EOS three-dimensional radiography versus computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Pomerantz, M.L. [University of California San Diego School of Medicine, Orthopaedic Surgery Department, San Diego, CA (United States); Glaser, Diana [Aurora Spine, Carlsbad, CA (United States); Doan, Josh [Orthopedic Biomechanics Research Center, San Diego, CA (United States); Kumar, Sita [University of California, San Diego, CA (United States); Edmonds, Eric W. [University of California San Diego School of Medicine, Orthopaedic Surgery Department, San Diego, CA (United States); Rady Children' s Hospital San Diego, Division of Orthopedic Surgery, San Diego, CA (United States)

    2014-10-17

    To validate femoral version measurements made from biplanar radiography (BR), three-dimensional (3D) reconstructions (EOS imaging, France) were made in differing rotational positions against the gold standard of computed tomography (CT). Two cadaveric femurs were scanned with CT and BR in five different femoral versions creating ten total phantoms. The native version was modified by rotating through a mid-diaphyseal hinge twice into increasing anteversion and twice into increased retroversion. For each biplanar scan, the phantom itself was rotated -10, -5, 0, +5 and +10 . Three-dimensional CT reconstructions were designated the true value for femoral version. Two independent observers measured the femoral version on CT axial slices and BR 3D reconstructions twice. The mean error (upper bound of the 95 % confidence interval), inter- and intraobserver reliability, and the error compared to the true version were determined for both imaging techniques. Interobserver intraclass correlation for CT axial images ranged from 0.981 to 0.991, and the intraobserver intraclass correlation ranged from 0.994 to 0.996. For the BR 3D reconstructions these values ranged from 0.983 to 0.998 and 0.982 to 0.998, respectively. For the CT measurements the upper bound of error from the true value was 5.4-7.5 , whereas for BR 3D reconstructions it was 4.0-10.1 . There was no statistical difference in the mean error from the true values for any of the measurements done with axial CT or BR 3D reconstructions. BR 3D reconstructions accurately and reliably provide clinical data on femoral version compared to CT even with rotation of the patient of up to 10 from neutral. (orig.)

  14. Automated quantification of pulmonary emphysema from computed tomography scans: comparison of variation and correlation of common measures in a large cohort

    Science.gov (United States)

    Keller, Brad M.; Reeves, Anthony P.; Yankelevitz, David F.; Henschke, Claudia I.

    2010-03-01

    The purpose of this work was to retrospectively investigate the variation of standard indices of pulmonary emphysema from helical computed tomographic (CT) scans as related to inspiration differences over a 1 year interval and determine the strength of the relationship between these measures in a large cohort. 626 patients that had 2 scans taken at an interval of 9 months to 15 months (μ: 381 days, σ: 31 days) were selected for this work. All scans were acquired at a 1.25mm slice thickness using a low dose protocol. For each scan, the emphysema index (EI), fractal dimension (FD), mean lung density (MLD), and 15th percentile of the histogram (HIST) were computed. The absolute and relative changes for each measure were computed and the empirical 95% confidence interval was reported both in non-normalized and normalized scales. Spearman correlation coefficients are computed between the relative change in each measure and relative change in inspiration between each scan-pair, as well as between each pair-wise combination of the four measures. EI varied on a range of -10.5 to 10.5 on a non-normalized scale and -15 to 15 on a normalized scale, with FD and MLD showing slightly larger but comparable spreads, and HIST having a much larger variation. MLD was found to show the strongest correlation to inspiration change (r=0.85, pemphysema index and fractal dimension have the least variability overall of the commonly used measures of emphysema and that they offer the most unique quantification of emphysema relative to each other.

  15. Handling of computational in vitro/in vivo correlation problems by Microsoft Excel: III. Convolution and deconvolution.

    Science.gov (United States)

    Langenbucher, Frieder

    2003-11-01

    Convolution and deconvolution are the classical in-vitro-in-vivo correlation tools to describe the relationship between input and weighting/response in a linear system, where input represents the drug release in vitro, weighting/response any body response in vivo. While functional treatment, e.g. in terms of polyexponential or Weibull distribution, is more appropriate for general survey or prediction, numerical algorithms are useful for treating actual experimental data. Deconvolution is not considered an algorithm by its own, but the inversion of a corresponding convolution. MS Excel is shown to be a useful tool for all these applications.

  16. Open and closed cortico-subcortical loops: A neuro-computational account of access to consciousness in the distractor-induced blindness paradigm.

    Science.gov (United States)

    Ebner, Christian; Schroll, Henning; Winther, Gesche; Niedeggen, Michael; Hamker, Fred H

    2015-09-01

    How the brain decides which information to process 'consciously' has been debated over for decades without a simple explanation at hand. While most experiments manipulate the perceptual energy of presented stimuli, the distractor-induced blindness task is a prototypical paradigm to investigate gating of information into consciousness without or with only minor visual manipulation. In this paradigm, subjects are asked to report intervals of coherent dot motion in a rapid serial visual presentation (RSVP) stream, whenever these are preceded by a particular color stimulus in a different RSVP stream. If distractors (i.e., intervals of coherent dot motion prior to the color stimulus) are shown, subjects' abilities to perceive and report intervals of target dot motion decrease, particularly with short delays between intervals of target color and target motion. We propose a biologically plausible neuro-computational model of how the brain controls access to consciousness to explain how distractor-induced blindness originates from information processing in the cortex and basal ganglia. The model suggests that conscious perception requires reverberation of activity in cortico-subcortical loops and that basal-ganglia pathways can either allow or inhibit this reverberation. In the distractor-induced blindness paradigm, inadequate distractor-induced response tendencies are suppressed by the inhibitory 'hyperdirect' pathway of the basal ganglia. If a target follows such a distractor closely, temporal aftereffects of distractor suppression prevent target identification. The model reproduces experimental data on how delays between target color and target motion affect the probability of target detection. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. The importance of bony impingement in restricting flexion after total knee arthroplasty: computer simulation model with clinical correlation.

    Science.gov (United States)

    Mizu-Uchi, Hideki; Colwell, Clifford W; Fukagawa, Shingo; Matsuda, Shuichi; Iwamoto, Yukihide; D'Lima, Darryl D

    2012-10-01

    We constructed patient-specific models from computed tomography data after total knee arthroplasty to predict knee flexion based on implant-bone impingement. The maximum flexion before impingement between the femur and the tibial insert was computed using a musculoskeletal modeling program (KneeSIM; LifeModeler, Inc, San Clemente, California) during a weight-bearing deep knee bend. Postoperative flexion was measured in a clinical cohort of 21 knees (low-flex group: 6 knees with 125° of flexion at 2 years). Average predicted flexion angles were within 2° of clinical measurements for the high-flex group. In the low-flex group, 4 cases had impingement involving the bone cut at the posterior condyle, and the average predicted knee flexion was 102° compared with 93° measured clinically. These results indicate that the level of the distal femoral resection should be carefully planned and that exposed bone proximal to the tips of the posterior condyles of the femoral component should be removed if there is risk of impingement. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Validating automated kidney stone volumetry in computed tomography and mathematical correlation with estimated stone volume based on diameter.

    Science.gov (United States)

    Wilhelm, Konrad; Miernik, Arkadiusz; Hein, Simon; Schlager, Daniel; Adams, Fabian; Benndorf, Matthias; Fritz, Benjamin; Langer, Mathias; Hesse, Albrecht; Schoenthaler, Martin; Neubauer, Jakob

    2018-06-02

    To validate AutoMated UroLithiasis Evaluation Tool (AMULET) software for kidney stone volumetry and compare its performance to standard clinical practice. Maximum diameter and volume of 96 urinary stones were measured as reference standard by three independent urologists. The same stones were positioned in an anthropomorphic phantom and CT scans acquired in standard settings. Three independent radiologists blinded to the reference values took manual measurements of the maximum diameter and automatic measurements of maximum diameter and volume. An "expected volume" was calculated based on manual diameter measurements using the formula: V=4/3 πr³. 96 stones were analyzed in the study. We had initially aimed to assess 100. Nine were replaced during data acquisition due of crumbling and 4 had to be excluded because the automated measurement did not work. Mean reference maximum diameter was 13.3 mm (5.2-32.1 mm). Correlation coefficients among all measured outcomes were compared. The correlation between the manual and automatic diameter measurements to the reference was 0.98 and 0.91, respectively (pvolumetry is possible and significantly more accurate than diameter-based volumetric calculations. To avoid bias in clinical trials, size should be measured as volume. However, automated diameter measurements are not as accurate as manual measurements.

  19. Dynamic computed tomography findings of atypical pulmonary hamartoma and it's pathologic correlations: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seung Baek; Jeong Yeon Joo Lee, Gee Won; Kim, Yeong Dae; Ahn, Hyo Yeong; Lee, Chang Hoon; Kim, Ah Rong; Lee, Ji Won [Medical Research Institute, Pusan National University Hospital, Busan (Korea, Republic of)

    2016-04-15

    We present the dynamic contrast-enhanced computed tomography (CT) findings of atypical pulmonary hamartoma with a rare histologic pattern in a 20-year-old male. CT showed a 3.4 cm lobulated mass with a 'tip of the iceberg' appearance in the medium bronchus of the right lower lobe. Dynamic contrast-enhanced CT demonstrated a heterogeneously and persistently enhancing mass. The CT Hounsfield unit (HU) measurements were: 17 HU pre-contrast, 32 HU at 1 minute, 44 HU at 2 minutes, 51 HU at 4 minutes, and 64 HU at 15 minutes. Pathologic examination after video-assisted thoracoscopic surgery disclosed a pulmonary hamartoma with a predominant fibroblastic component.

  20. Clinical application of calculated split renal volume using computed tomography-based renal volumetry after partial nephrectomy: Correlation with technetium-99m dimercaptosuccinic acid renal scan data.

    Science.gov (United States)

    Lee, Chan Ho; Park, Young Joo; Ku, Ja Yoon; Ha, Hong Koo

    2017-06-01

    To evaluate the clinical application of computed tomography-based measurement of renal cortical volume and split renal volume as a single tool to assess the anatomy and renal function in patients with renal tumors before and after partial nephrectomy, and to compare the findings with technetium-99m dimercaptosuccinic acid renal scan. The data of 51 patients with a unilateral renal tumor managed by partial nephrectomy were retrospectively analyzed. The renal cortical volume of tumor-bearing and contralateral kidneys was measured using ImageJ software. Split estimated glomerular filtration rate and split renal volume calculated using this renal cortical volume were compared with the split renal function measured with technetium-99m dimercaptosuccinic acid renal scan. A strong correlation between split renal function and split renal volume of the tumor-bearing kidney was observed before and after surgery (r = 0.89, P volumetry had a strong correlation with the split renal function measured using technetium-99m dimercaptosuccinic acid renal scan. Computed tomography-based split renal volume measurement before and after partial nephrectomy can be used as a single modality for anatomical and functional assessment of the tumor-bearing kidney. © 2017 The Japanese Urological Association.

  1. Correlative single photon emission computed tomography imaging of [{sup 123}I]altropane binding in the rat model of Parkinson's

    Energy Technology Data Exchange (ETDEWEB)

    Gleave, Jacqueline A. [Department of Pathology and Molecular Medicine, McMaster University, 1200 Main Street West, Hamilton, Ontario, L8N 3Z5 (Canada); Farncombe, Troy H.; Saab, Chantal [Department of Nuclear Medicine, Hamilton Health Sciences, Hamilton, Ontario, L8N 3Z5 (Canada); Doering, Laurie C., E-mail: doering@mcmaster.ca [Department of Pathology and Molecular Medicine, McMaster University, 1200 Main Street West, Hamilton, Ontario, L8N 3Z5 (Canada)

    2011-07-15

    Introduction: This study used the dopamine transporter (DAT) probe, [{sup 123}I]-2{beta}-carbomethoxy-3{beta}-(4-fluorophenyl)-N-(3-iodo-E-allyl)nortropane ([{sup 123}I]altropane), to assess the DAT levels in the 6-hydroxydopamine rat model of Parkinson's disease. We sought to assess if the right to left [{sup 123}I]altropane striatal ratios correlated with dopamine content in the striatum and substantia nigra and with behavioural outcomes. Methods: [{sup 123}I]altropane images taken pre- and postlesion were acquired before and after the transplantation of neural stem/progenitor cells. The images obtained using [{sup 123}I]altropane and single photon emission computed tomography (SPECT) were compared with specific behavioural tests and the dopamine content assessed by high-performance liquid chromatography. Results: [{sup 123}I]altropane binding correlated with the content of dopamine in the striatum; however, [{sup 123}I]altropane binding did not correlate with the dopamine content in the substantia nigra. There was a significant correlation of altropane ratios with the cylinder test and the postural instability test, but not with amphetamine rotations. The low coefficient of determination (r{sup 2}) for these correlations indicated that [{sup 123}I]altropane SPECT was not a good predictor of behavioural outcomes. Conclusion: Our data reveal that [{sup 123}I]altropane predicts the integrity of the striatal dopamine nerve terminals, but does not predict the integrity of the nigrostriatal system. [{sup 123}I]altropane could be a useful marker to measure dopamine content in cell replacement therapies; however, it would not be able to evaluate outcomes for neuroprotective strategies.

  2. Ischemic Volume and Neurological Deficit: Correlation of Computed Tomography Perfusion with the National Institutes of Health Stroke Scale Score in Acute Ischemic Stroke.

    Science.gov (United States)

    Furlanis, Giovanni; Ajčević, Miloš; Stragapede, Lara; Lugnan, Carlo; Ridolfi, Mariana; Caruso, Paola; Naccarato, Marcello; Ukmar, Maja; Manganotti, Paolo

    2018-04-30

    The National Institutes of Health Stroke Scale (NIHSS) is the most adopted stroke patients' evaluation tool in emergency settings to assess the severity of stroke and to determine the patients' eligibility for specific treatments. Computed tomography perfusion (CTP) is crucial to identify salvageable tissue that can benefit from the reperfusion treatment. The aim of this study is to identify the relation between the NIHSS scores and the hypoperfused volumes evaluated by CTP in patients with hyperacute ischemic stroke. This retrospective study was conducted on 105 patients with ischemic stroke who underwent NIHSS assessment and CTP in the hyperacute phase. Hypoperfused volume was evaluated by CTP maps processed with semi-automatic algorithm. An analysis was conducted to determine the degree of correlation between the NIHSS scores and the ischemic lesion volumes and to investigate the relation between the anterior and the posterior circulation strokes, as well as between the right and the left hemispheric strokes. A significant correlation was found between ischemic volume and NIHSS score at baseline (r = .82; P correlation was identified in the anterior circulation stroke (r = .76; P correlated for the left and the right hemispheric strokes (r = .83 and .81; P correlation between the baseline NIHSS score and the ischemic volume estimated by CTP. We confirmed that NIHSS is a reliable predictor of perfusion deficits in acute ischemic stroke. CTP allows fast imaging assessment in the hyperacute phase. The results highlight the importance of these diagnostic tools in the assessment of stroke severity and in acute decision-making. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  3. The birth canal: correlation between the pubic arch angle, the interspinous diameter, and the obstetrical conjugate: a computed tomography biometric study in reproductive age women.

    Science.gov (United States)

    Perlman, Sharon; Raviv-Zilka, Lisa; Levinsky, Denis; Gidron, Ayelet; Achiron, Reuven; Gilboa, Yinon; Kivilevitch, Zvi

    2018-04-22

    Assessment of pelvic configuration is an important factor in the prediction of a successful vaginal birth. However, manual evaluation of the pelvis is practically a vanishing art, and imaging techniques are not available as a real-time bed-side tool. Unlike the obstetrical conjugate diameter (OC) and inter spinous diameter (ISD), the pubic arch angle (PAA) can be easily measured by transperineal ultrasound. Three-dimensional computed tomography bone reconstructions were used to measure the three main birth canal diameters, evaluate the correlation between them, and establish the normal reference range for the inlet, mid-, and pelvic outlet. Measurements of the PAA, obstetric conjugate (OC), and ISD were performed offline using three-dimensional post processing reconstruction in bone algorithm application of the pelvis on examinations performed for suspected renal colic in nonpregnant reproductive age woman. The mean of two measurements was used for statistical analysis which included reproducibility of measurements, regression curve estimation between PAA, OC, and ISD, and calculation of the respective reference range centiles for each PAA degree. Two hundred ninety-eight women comprised the study group. The mean ± SD of the PAA, ISD, and OC were 104.9° (±7.4), 103.8 mm (±7.3), and 129.9 mm (±8.3), respectively. The intra- and interobserver agreement defined by the intraclass correlation coefficient (ICC) was excellent for all parameters (range 0.905-0.993). A significant positive correlation was found between PAA and ISD and between PAA and OCD (Pearson's correlation = 0.373 (p correlation between the three pelvic landmarks with greatest impact on the prediction of a successful vaginal delivery: the PAA which is easily measured sonographically and the ISD and OC which are not measurable by ultrasound. This correlation may serve as a basis for future studies to assess its utility and prognostic value for a safe vaginal delivery.

  4. Correlation-based model of artificially induced plasticity in motor cortex by a bidirectional brain-computer interface.

    Directory of Open Access Journals (Sweden)

    Guillaume Lajoie

    2017-02-01

    Full Text Available Experiments show that spike-triggered stimulation performed with Bidirectional Brain-Computer-Interfaces (BBCI can artificially strengthen connections between separate neural sites in motor cortex (MC. When spikes from a neuron recorded at one MC site trigger stimuli at a second target site after a fixed delay, the connections between sites eventually strengthen. It was also found that effective spike-stimulus delays are consistent with experimentally derived spike-timing-dependent plasticity (STDP rules, suggesting that STDP is key to drive these changes. However, the impact of STDP at the level of circuits, and the mechanisms governing its modification with neural implants remain poorly understood. The present work describes a recurrent neural network model with probabilistic spiking mechanisms and plastic synapses capable of capturing both neural and synaptic activity statistics relevant to BBCI conditioning protocols. Our model successfully reproduces key experimental results, both established and new, and offers mechanistic insights into spike-triggered conditioning. Using analytical calculations and numerical simulations, we derive optimal operational regimes for BBCIs, and formulate predictions concerning the efficacy of spike-triggered conditioning in different regimes of cortical activity.

  5. Percutaneous computed tomography-guided core needle biopsy of soft tissue tumors: results and correlation with surgical specimen analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chojniak, Rubens; Grigio, Henrique Ramos; Bitencourt, Almir Galvao Vieira; Pinto, Paula Nicole Vieira; Tyng, Chiang J.; Cunha, Isabela Werneck da; Aguiar Junior, Samuel; Lopes, Ademar, E-mail: chojniak@uol.com.br [Hospital A.C. Camargo, Sao Paulo, SP (Brazil)

    2012-09-15

    Objective: To evaluate the efficacy of percutaneous computed tomography (CT)-guided core needle biopsy of soft tissue tumors in obtaining appropriate samples for histological analysis, and compare its diagnosis with the results of the surgical pathology as available. Materials and Methods: The authors reviewed medical records, imaging and histological reports of 262 patients with soft-tissue tumors submitted to CT-guided core needle biopsy in an oncologic reference center between 2003 and 2009. Results: Appropriate samples were obtained in 215 (82.1%) out of the 262 patients. The most prevalent tumors were sarcomas (38.6%), metastatic carcinomas (28.8%), benign mesenchymal tumors (20.5%) and lymphomas (9.3%). Histological grading was feasible in 92.8% of sarcoma patients, with the majority of them (77.9%) being classified as high grade tumors. Out of the total sample, 116 patients (44.3%) underwent surgical excision and diagnosis confirmation. Core biopsy demonstrated 94.6% accuracy in the identification of sarcomas, with 96.4% sensitivity and 89.5% specificity. A significant intermethod agreement about histological grading was observed between core biopsy and surgical resection (p < 0.001; kappa = 0.75). Conclusion: CT-guided core needle biopsy demonstrated a high diagnostic accuracy in the evaluation of soft tissue tumors as well as in the histological grading of sarcomas, allowing an appropriate therapeutic planning (author)

  6. Correlation-based model of artificially induced plasticity in motor cortex by a bidirectional brain-computer interface.

    Science.gov (United States)

    Lajoie, Guillaume; Krouchev, Nedialko I; Kalaska, John F; Fairhall, Adrienne L; Fetz, Eberhard E

    2017-02-01

    Experiments show that spike-triggered stimulation performed with Bidirectional Brain-Computer-Interfaces (BBCI) can artificially strengthen connections between separate neural sites in motor cortex (MC). When spikes from a neuron recorded at one MC site trigger stimuli at a second target site after a fixed delay, the connections between sites eventually strengthen. It was also found that effective spike-stimulus delays are consistent with experimentally derived spike-timing-dependent plasticity (STDP) rules, suggesting that STDP is key to drive these changes. However, the impact of STDP at the level of circuits, and the mechanisms governing its modification with neural implants remain poorly understood. The present work describes a recurrent neural network model with probabilistic spiking mechanisms and plastic synapses capable of capturing both neural and synaptic activity statistics relevant to BBCI conditioning protocols. Our model successfully reproduces key experimental results, both established and new, and offers mechanistic insights into spike-triggered conditioning. Using analytical calculations and numerical simulations, we derive optimal operational regimes for BBCIs, and formulate predictions concerning the efficacy of spike-triggered conditioning in different regimes of cortical activity.

  7. Correlations between regional cerebral blood flow and age-related brain atrophy: a quantitative study with computed tomography and the xenon-133 inhalation method

    International Nuclear Information System (INIS)

    Yamaguchi, T.; Hatazawa, J.; Kubota, K.; Abe, Y.; Fujiwara, T.; Matsuzawa, T.

    1983-01-01

    One hundred and two subjects (40 men and 62 women) neither having a history of neurologic deficits nor showing organic lesions on computed tomographic examination of the brain were studied. Ages of the subjects ranged from 26 to 81 years. Regional cerebral blood flow was measured by the xenon-133 inhalation method, and the volume percentage of brain with respect to the cranial cavity (craniocerebral index) was calculated by means of computer programs. Regional cerebral blood flow was computed as the fast component of two-compartmental analysis and as the initial slope index value. The percentage of each subject's craniocerebral index in relation to the standard for subjects with non-atrophied brains (brain volume index) was calculated as the indicator of brain atrophy. Both the mean brain fast component values and the mean brain initial slope index values correlated closely with the brain volume index in the elderly. Low cerebral blood flow values coincided with loss of brain substance in the final stage of age-related brain atrophy, but not in the intermediate stage

  8. Fracture Analysis of Vessels. Oak Ridge FAVOR, v06.1, Computer Code: Theory and Implementation of Algorithms, Methods, and Correlations

    Energy Technology Data Exchange (ETDEWEB)

    Williams, P. T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dickson, T. L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yin, S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2007-12-01

    The current regulations to insure that nuclear reactor pressure vessels (RPVs) maintain their structural integrity when subjected to transients such as pressurized thermal shock (PTS) events were derived from computational models developed in the early-to-mid 1980s. Since that time, advancements and refinements in relevant technologies that impact RPV integrity assessment have led to an effort by the NRC to re-evaluate its PTS regulations. Updated computational methodologies have been developed through interactions between experts in the relevant disciplines of thermal hydraulics, probabilistic risk assessment, materials embrittlement, fracture mechanics, and inspection (flaw characterization). Contributors to the development of these methodologies include the NRC staff, their contractors, and representatives from the nuclear industry. These updated methodologies have been integrated into the Fracture Analysis of Vessels -- Oak Ridge (FAVOR, v06.1) computer code developed for the NRC by the Heavy Section Steel Technology (HSST) program at Oak Ridge National Laboratory (ORNL). The FAVOR, v04.1, code represents the baseline NRC-selected applications tool for re-assessing the current PTS regulations. This report is intended to document the technical bases for the assumptions, algorithms, methods, and correlations employed in the development of the FAVOR, v06.1, code.

  9. Findings in multidetector computed tomography in the diagnosis of hepatocellular carcinoma in patients with cirrhosis and correlation with pathology of liver explants

    International Nuclear Information System (INIS)

    Haberman, D.; Castignola, M.; Mela, M.; Paladini, H.; Santilli, J.P.; Gruz, F.; Gondolesi, G.

    2013-01-01

    Objectives: To describe the imagenological behavior of hepatocellular carcinoma in cirrhotic patients using a dynamic multidetector computed tomography (MDCT) technique, and correlate these findings with histological tumor grades. Materials and methods: A retrospective, descriptive observational study was conducted to evaluate 51 nodules in 32 liver transplant patients diagnosed with liver cirrhosis. The pathology of liver explants was used as a reference. Nodules with hepatocellular carcinoma histopathology were retrospectively analyzed by computed tomography scans performed pre-transplant. Using a dynamic multidetector computed tomography technique, we evaluated the most common imagenological behavior reported in the literature: arterial enhancement, washout, capsule, and intratumoral arterial vessels. Results: Forty-six of 51 (90%) tumors showed arterial enhancement. Of the 46 tumors with arterial enhancement, 39 (85%) had washout in portal-late phase. Five of 51 (10%) were hypovascular. Twenty-two of 51 (43%) had capsule and 12 of 51 (24%) showed intratumoral arterial vessels. The more frequent image combination was the combination of arterial enhancement and washout (39 of 51 tumors or 76%). The most frequent histological grade was II (35 of 51 tumors or 69%). Statistically significant relationships were found between histological grade tumors and imagenological behavior: arterial enhancement and hypovascular. Conclusion: In our population, arterial enhancement with washout in portal-late phases was observed in most of the tumors. Our results are consistent with previously reported studies, demonstrating the high reliability of this imaging pattern for the diagnosis of hepatocellular carcinoma. (authors) [es

  10. Measurement of tumor volumes of hepatocellular carcinoma (HCC) by computed tomography (CT). Correlation with several tumor markers

    Energy Technology Data Exchange (ETDEWEB)

    Yoneshima, Manabu; Sawabu, Norio; Toya, Daishu

    1984-09-01

    Tumor volumes of HCC were measured by CT using planimeter and the clinical value of this measurement was evaluated by comparing several tumor markers. Tumor volumes measured by CT roughly agreed with those measured by angiography. In some cases, volumes from ultrasonography were smaller than those from CT and angiography. Tumor volumes measured by CT correlated significantly with the levels of ..cap alpha..-fetoprotein (AFP) but didn't relate to the presence of hepatoma specific ..gamma..-GTP isoenzyme (novel ..gamma..-GTP) nor to the values and positivities of LAI assay. In small HCCs (<=30 cm/sup 3/), the presence of novel ..gamma..-GTP and the levels of AFP were significantly lower than for larger tumors of HCC, but LAI assay wasn't lower. The non-tumorous volumes and the ratio of the non-tumorous volume to the whole liver volume didn't relate to the tests of liver function except for the presence of ascites.

  11. Diagnosis of chronic rhino sinusitis in patients with cystic fibrosis: correlation between anamnesis, nasal endoscopy and computed tomography

    International Nuclear Information System (INIS)

    Boari, Leticia; Castro Junior, Ney Penteado de

    2005-01-01

    The sinonasal involvement is one of the most common manifestations in cystic fibrosis. Data show a high incidence of chronic rhino sinusitis in these patients. Although it has been found radiographic opacification of the sinus in more than 90% of cases, few are symptomatic. So that, it is difficult to recognize nasossinusal disease in patients with cystic fibrosis. Questionnaire, nasal endoscopy and CT-scan are very important methods in this approach. Aim: to evaluate the diagnosis of chronic rhino sinusitis in patients with cystic fibrosis by anamnesis, nasal endoscopy and CT-scan and compare those results.Study Design: Clinical prospective. Material and method: evaluation of 34 patients - older than 6 years and with a confirmed diagnoses of cystic fibrosis - by anamnesis (questionnaire), nasal endoscopy (score Lund-Kennedy) and CT-scan (score Lund-Mackay). Results: chronic rhino sinusitis was confirmed in: 20,58% of cases by the questionnaire, 73,52% of the cases by the nasal endoscopy and in 93,54% of the cases by the CT-scan. The results showed significant differences. The correlation between nasal endoscopy score (Lund-Kennedy score) and CT-scan score (Lund-Mackay score) was statistically significant. Conclusion: the diagnosis of chronic rhino sinusitis was statistically different between the three methods. It was higher in imaging analysis and lower in questionnaire. The nasal endoscopy is an excellent method to evaluate nasossinusal disease in cystic fibrosis. (author)

  12. Morphological evolution and internal strain mapping of pomelo peel using X-ray computed tomography and digital volume correlation

    KAUST Repository

    Wang, B.

    2017-10-15

    Cellular microstructures within natural materials enlighten and promote the development of novel materials and structures in the industrial and engineering fields. Characterization of the microstructures and mechanical properties of these natural materials can help to understand the morphology-related mechanical properties and guide the structural optimization in industrial design. Among these natural cellular materials, pomelo peels, having a foam-like hierarchical microstructure, represent an ideal model for developing materials with high energy absorption efficiency. In this work, by combining X-ray tomographic imaging technique and digital volume correlation (DVC), in-situ stepwise uniaxial compression tests were performed to quantify the internal morphological evolution and kinematic responses of pomelo peel samples during compression. Via these experiments, the varying microstructure features and thus diverse resistance to compression from endocarp to exocarp are examined, and the evolution of both bundles bending and large strain domain from endocarp to mesocarp are explored. Based on the experimental results, the microstructure-related mechanical properties of pomelo peels in response to compressive loading that demonstrates nearly linear morphology-mechanics relationship were revealed.

  13. Correlation between angiogenesis and reduction ratio measured using 201Tl chloride single photon emission computed tomography in patients with oral cavity squamous cell carcinoma

    International Nuclear Information System (INIS)

    Suzuki, Aya; Togawa, Takashi; Omura, Ken

    2004-01-01

    The aim of this study is to examine the correlation between tumor angiogenesis and response to preoperative radiotherapy evaluated using 201 Tl single photon emission computed tomography (Tl SPECT) in oral cavity squamous cell carcinoma (SCC). Tl SPECTs before and after preoperative radiotherapy were obtained from 11 patients diagnosed with SCC in oral cavity. Regions of interest were set around the tumor and scalp respectively, and the ratio of mean counts in the tumor to those in the scalp was calculated (T/N). Immunohistochemical staining for investigating microvessel density of pre-treatment biopsy specimen was performed using CD31 monoclonal antibody. We compared microvessel density with semi-quantitative parameters obtained using Tl SPECT (T/N at pre- an post-treatment, reduction ratio) and prognosis. The subgroup with higher microvessel density showed a significantly higher reduction ratio than the one with lower microvessel density. Regarding prognosis, the subgroup with locoregional recurrent disease exhibited a significantly higher microvessel density than the one without recurrence. In SCC of the oral cavity, there was a significant correlation between microvessel density and response to preoperative radiotherapy. Namely, it was revealed that change of 201 Tl uptake after preoperative radiotherapy correlated with tumor angiogenesis of oral cavity SCC. (author)

  14. Incidental Findings in Abdominal Dual-Energy Computed Tomography: Correlation Between True Noncontrast and Virtual Noncontrast Images Considering Renal and Liver Cysts and Adrenal Masses.

    Science.gov (United States)

    Slebocki, Karin; Kraus, Bastian; Chang, De-Hua; Hellmich, Martin; Maintz, David; Bangard, Christopher

    To assess correlation between attenuation measurements of incidental findings in abdominal second generation dual-energy computed tomography (CT) on true noncontrast (TNC) and virtual noncontrast (VNC) images. Sixty-three patients underwent arterial dual-energy CT (Somatom Definition Flash, Siemens; pitch factor, 0.75-1.0; gantry rotation time, 0.28 seconds) after endovascular aneurysm repair, consisting of a TNC single energy CT scan (collimation, 128 × 0.6 mm; 120 kVp) and a dual-energy arterial phase scan (collimation, 32 × 0.6 mm, 140 and 100 kVp; blended, 120 kVp data set). Attenuation measurements in Hounsfield units (HU) of liver parenchyma and incidental findings like renal and hepatic cysts and adrenal masses on TNC and VNC images were done by drawing regions of interest. Statistical analysis was performed by paired t test and Pearson correlation. Incidental findings were detected in 56 (89%) patients. There was excellent correlation for both renal (n = 40) and hepatic cysts (n = 12) as well as adrenal masses (n = 6) with a Pearson correlation of 0.896, 0.800, and 0.945, respectively, and mean attenuation values on TNC and VNC images of 10.6 HU ± 12.8 versus 5.1 HU ± 17.5 (attenuation value range from -8.8 to 59.1 HU vs -11.8 to 73.4 HU), 6.4 HU ± 5.8 versus 6.3 HU ± 4.6 (attenuation value range from 2.0 to 16.2 HU vs -3.0 to 15.9 HU), and 12.8 HU ± 11.2 versus 12.4 HU ± 10.2 (attenuation value range from -2.3 to 27.5 HU vs -2.2 to 23.6 HU), respectively. As proof of principle, liver parenchyma measurements also showed excellent correlation between TNC and VNC (n = 40) images with a Pearson correlation of 0.839 and mean attenuation values on TNC and VNC images of 47.2 HU ± 10.5 versus 43.8 HU ± 8.7 (attenuation value range from 21.9 to 60.2 HU vs 4.5 to 65.3 HU). In conclusion, attenuation measurements of incidental findings like renal cysts or adrenal masses on TNC and VNC images derived from second generation dual-energy CT scans show excellent

  15. Accessory Renal Artery Stenosis and Hypertension: Are These Correlated? Evaluation Using Multidetector-Row Computed Tomographic Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saba, L.; Sanfilippo, R.; Montisci, R.; Conti, M.; Mallarini, G. (Dept. of Imaging Science and Dept. of Vascular Surgery, Policlinico Universitario, Cagliari (Italy))

    2008-04-15

    Background: Renal artery stenosis may produce hypertension, and this condition is referred to as renovascular hypertension (RVH). Purpose: To evaluate, by using multidetector-row spiral computed tomographic angiography (MDCTA), whether a relationship between accessory renal artery stenosis and hypertension may be hypothesized. Material and Methods: 214 patients (142 males, 72 females; mean age 66 years) who had previously undergone an MDCTA to study the abdominal vasculature were retrospectively studied. Patients with renal artery stenosis (RAS) were excluded from this analysis. The patients were studied by means of a four-detector-row CT, and scans were obtained after intravenous bolus administration of 110-140 ml of a nonionic contrast material with a 3-6 ml/s flow rate. As a second step, by means of statistical analysis, hypertension data were compared with findings of accessory artery stenosis. Two radiologists first independently reviewed the MDCTA images and then, in case of disagreement, in consensus. Interobserver agreement was calculated for all measurements. Results: The overall number of detected accessory renal arteries was 74 in 56 of the 214 patients. Accessory renal artery stenosis was detected in 21 of the 56 patients. There was a difference in the prevalence of hypertension between patients with (n = 21) and without (n = 35) accessory renal artery stenosis (P = 0.0187). Interobserver agreement was good (kappa value 0.733). Conclusion: Any statistical association between the presence of accessory renal artery stenosis and hypertension could not be disclosed. However, accessory renal artery stenosis, detected by MDCTA, is an important pathological sign that the radiologist has to assess in the light of its possible association with hypertension

  16. Computed tomography and magnetic resonance imaging findings of solitary fibrous tumors in the pelvis: Correlation with histopathological findings

    International Nuclear Information System (INIS)

    Zhang Weidong; Chen Jianyu; Cao Yun; Liu Qingyu; Luo Rongguang

    2011-01-01

    Objective: We aimed to analyze the computed tomography (CT) and magnetic resonance imaging (MRI) findings of pelvic solitary fibrous tumors (SFTs) and to improve the diagnostic efficacy for such tumors. Methods: Six cases of pelvic SFTs confirmed by histopathology were analyzed retrospectively. Of the 6 patients, 4 had undergone CT scanning, and 2 had undergone magnetic resonance imaging. All the patients had undergone unenhanced and contrast-enhanced examinations, and 2 had also undergone dynamic CT enhancement examination. Image characteristics such as shape, size, number, edge, attenuation or intensity for each lesion before and after contrast enhancement were analyzed and compared with the pathomorphology of the tumors. Results: All the 6 cases showed oval or rounded and well-defined masses. Unenhanced CT images showed heterogeneous masses with patchy, necrotic foci in 3 cases and homogeneous mass in 1 case. None of the tumors showed calcification. Contrast-enhanced CT images showed marked, heterogeneous enhancement in the first and second cases. Dynamic enhancement scan demonstrated mild homogeneous enhancement in the third case and mild prolonged, delayed enhancement and washout in the fourth case. T1-weighted MR images showed heterogeneous mild hypointense lesion with linear hyperintensity in 1 case, and homogeneous isointensity in the other. T2-weighted images showed heterogeneous mixed intensity in 1 case and mostly hyperintensive lesion with hypointense foci in another case. A case showed marked heterogeneous enhancement and another showed marked homogeneous enhancement on contrast-enhanced T1-weighted images. Conclusion: Radiological findings of pelvic SFTs are variable and nonspecific. However, a well-defined, ovoid or rounded mass with hypointense on MR T2-weighted images and variable enhancement on CT and MR images may suggest the diagnosis of SFTs. Pelvic SFTs should be included in the differential diagnosis of regional tumors.

  17. On the improvement of two-dimensional curvature computation and its application to turbulent premixed flame correlations

    International Nuclear Information System (INIS)

    Chrystie, R S M; Burns, I S; Hult, J; Kaminski, C F

    2008-01-01

    Measurement of curvature of the flamefront of premixed turbulent flames is important for the validation of numerical models for combustion. In this work, curvature is measured from contours that outline the flamefront, which are generated from laser-induced fluorescence images. The contours are inherently digitized, resulting in pixelation effects that lead to difficulties in computing curvature of the flamefront accurately. A common approach is to fit functions locally to short sections along the flame contour, and this approach is also followed in this work; the method helps smoothen the pixelation before curvature is measured. However, the length and degree of the polynomial, and hence the amount of smoothing, must be correctly set in order to maximize the precision and accuracy of the curvature measurements. Other researchers have applied polynomials of different orders and over different segment lengths to circles of known curvature as a test to determine the appropriate choice of polynomial; it is shown here that this method results in a sub-optimal choice of polynomial function. Here, we determine more suitable polynomial functions through use of a circle whose radius is sinusoidally modulated. We show that this leads to a more consistent and reliable choice for the local polynomial functions fitted to experimental data. A polynomial function thus determined is then applied to flame contour data to measure curvature of experimentally acquired flame contours. The results show that there is an enhancement in local flame speed at sections of the flamefront with a non-zero curvature, and this agrees with numerical models

  18. Accessory Renal Artery Stenosis and Hypertension: Are These Correlated? Evaluation Using Multidetector-Row Computed Tomographic Angiography

    International Nuclear Information System (INIS)

    Saba, L.; Sanfilippo, R.; Montisci, R.; Conti, M.; Mallarini, G.

    2008-01-01

    Background: Renal artery stenosis may produce hypertension, and this condition is referred to as renovascular hypertension (RVH). Purpose: To evaluate, by using multidetector-row spiral computed tomographic angiography (MDCTA), whether a relationship between accessory renal artery stenosis and hypertension may be hypothesized. Material and Methods: 214 patients (142 males, 72 females; mean age 66 years) who had previously undergone an MDCTA to study the abdominal vasculature were retrospectively studied. Patients with renal artery stenosis (RAS) were excluded from this analysis. The patients were studied by means of a four-detector-row CT, and scans were obtained after intravenous bolus administration of 110-140 ml of a nonionic contrast material with a 3-6 ml/s flow rate. As a second step, by means of statistical analysis, hypertension data were compared with findings of accessory artery stenosis. Two radiologists first independently reviewed the MDCTA images and then, in case of disagreement, in consensus. Interobserver agreement was calculated for all measurements. Results: The overall number of detected accessory renal arteries was 74 in 56 of the 214 patients. Accessory renal artery stenosis was detected in 21 of the 56 patients. There was a difference in the prevalence of hypertension between patients with (n = 21) and without (n = 35) accessory renal artery stenosis (P = 0.0187). Interobserver agreement was good (kappa value 0.733). Conclusion: Any statistical association between the presence of accessory renal artery stenosis and hypertension could not be disclosed. However, accessory renal artery stenosis, detected by MDCTA, is an important pathological sign that the radiologist has to assess in the light of its possible association with hypertension

  19. Correlating Computed Tomography Perfusion Changes in the Pharyngeal Constrictor Muscles During Head-and-Neck Radiotherapy to Dysphagia Outcome

    Energy Technology Data Exchange (ETDEWEB)

    Truong, Minh Tam, E-mail: mitruong@bu.edu [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); Department of Radiology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); Lee, Richard [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); Saito, Naoko [Department of Radiology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); Qureshi, Muhammad M. [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); Ozonoff, Al [Department of Biostatistics, Boston University School of Public Health, Boston, MA (United States); Romesser, Paul B. [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); Wang, Jimmy; Sakai, Osamu [Department of Radiology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States)

    2012-02-01

    Purpose: To measure changes in perfusion of the pharyngeal constrictor muscles (PCM) using CT perfusion (CTP) imaging during a course of definitive radiotherapy (RT) in head-and-neck cancer (HNC) patients and correlate with dysphagia outcome after RT. Methods and Materials: Fifteen HNC patients underwent CTP imaging of the PCM at baseline and Weeks 2, 4, and 6 during RT and 6 weeks after RT. Blood flow and blood volume were measured in the PCM, and percentage change from baseline scan was determined. A single physician-based assessment of dysphagia was performed every 3 months after RT using the Common Terminology Criteria for Adverse Events, version 3.0 grading system. Results: With a median follow-up of 28 months (range, 6-44 months), Grade 3 dysphagia was present in 7 of 15 patients, and 8 patients experienced Grade 0-2 dysphagia. The CTP parameters at Week 2 of RT demonstrated an increase in mean PCM blood flow of 161.9% vs. 12.3% (p = 0.007) and an increase in mean PCM blood volume of 96.6% vs. 8.7% (p = 0.039) in patients with 6-month post-RT Grade 3 dysphagia and Grade 0-2 dysphagia, respectively. On multivariate analysis, when adjusting for smoking history, tumor volume, and baseline dysphagia status, an increase in blood flow in the second week of RT was significant for 3- and 6-month Grade 3 dysphagia (p < 0.05). Conclusions: Perfusion changes in the PCM during Week 2 of RT in the PCM may predict the severity of dysphagia after HNC RT.

  20. Correlating Computed Tomography Perfusion Changes in the Pharyngeal Constrictor Muscles During Head-and-Neck Radiotherapy to Dysphagia Outcome

    International Nuclear Information System (INIS)

    Truong, Minh Tam; Lee, Richard; Saito, Naoko; Qureshi, Muhammad M.; Ozonoff, Al; Romesser, Paul B.; Wang, Jimmy; Sakai, Osamu

    2012-01-01

    Purpose: To measure changes in perfusion of the pharyngeal constrictor muscles (PCM) using CT perfusion (CTP) imaging during a course of definitive radiotherapy (RT) in head-and-neck cancer (HNC) patients and correlate with dysphagia outcome after RT. Methods and Materials: Fifteen HNC patients underwent CTP imaging of the PCM at baseline and Weeks 2, 4, and 6 during RT and 6 weeks after RT. Blood flow and blood volume were measured in the PCM, and percentage change from baseline scan was determined. A single physician-based assessment of dysphagia was performed every 3 months after RT using the Common Terminology Criteria for Adverse Events, version 3.0 grading system. Results: With a median follow-up of 28 months (range, 6–44 months), Grade 3 dysphagia was present in 7 of 15 patients, and 8 patients experienced Grade 0–2 dysphagia. The CTP parameters at Week 2 of RT demonstrated an increase in mean PCM blood flow of 161.9% vs. 12.3% (p = 0.007) and an increase in mean PCM blood volume of 96.6% vs. 8.7% (p = 0.039) in patients with 6-month post-RT Grade 3 dysphagia and Grade 0–2 dysphagia, respectively. On multivariate analysis, when adjusting for smoking history, tumor volume, and baseline dysphagia status, an increase in blood flow in the second week of RT was significant for 3- and 6-month Grade 3 dysphagia (p < 0.05). Conclusions: Perfusion changes in the PCM during Week 2 of RT in the PCM may predict the severity of dysphagia after HNC RT.

  1. Voxel-Based Correlation between Coregistered Single-Photon Emission Computed Tomography and Dynamic Susceptibility Contrast Magnetic Resonance Imaging in Subjects with Suspected Alzheimer Disease

    International Nuclear Information System (INIS)

    Cavallin, L.; Axelsson, R.; Wahlund, L.O.; Oeksengard, A.R.; Svensson, L.; Juhlin, P.; Wiberg, M. Kristoffersen; Frank, A.

    2008-01-01

    Background: Current diagnosis of Alzheimer disease is made by clinical, neuropsychologic, and neuroimaging assessments. Neuroimaging techniques such as magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) could be valuable in the differential diagnosis of Alzheimer disease, as well as in assessing prognosis. Purpose: To compare SPECT and MRI in a cohort of patients examined for suspected dementia, including patients with no objective cognitive impairment (control group), mild cognitive impairment (MCI), and Alzheimer disease (AD). Material and Methods: 24 patients, eight with AD, 10 with MCI, and six controls, were investigated with SPECT using 99m Tc-hexamethylpropyleneamine oxime (HMPAO, Ceretec; GE Healthcare Ltd., Little Chalsont UK) and dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) with a contrast-enhancing gadobutrol formula (Gadovist; Bayer Schering Pharma, Berlin, Germany). Voxel-based correlation between coregistered SPECT and DSC-MR images was calculated. Region-of-interest (ROI) analyses were then performed in 24 different brain areas using brain registration and analysis of SPECT studies (BRASS; Nuclear Diagnostics AB, Stockholm (SE)) on both SPECT and DSC-MRI. Results: Voxel-based correlation between coregistered SPECT and DSC-MR showed a high correlation, with a mean correlation coefficient of 0.94. ROI analyses of 24 regions showed significant differences between the control group and AD patients in 10 regions using SPECT and five regions in DSC-MR. Conclusion: SPECT remains superior to DSC-MRI in differentiating normal from pathological perfusion, and DSC-MRI could not replace SPECT in the diagnosis of patients with Alzheimer disease

  2. Wireless Access

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Wireless Access. Wireless connect to the Base station. Easy and Convenient access. Costlier as compared to the wired technology. Reliability challenges. We see it as a complementary technology to the DSL.

  3. Identification of Serine Conformers by Matrix-Isolation IR Spectroscopy Aided by Near-Infrared Laser Induced Conformational Change, 2D Correlation Analysis, and Quantum Mechanical Anharmonic Computations

    Science.gov (United States)

    Najbauer, Eszter E.; Bazsó, Gábor; Apóstolo, Rui; Fausto, Rui; Biczysko, Malgorzata; Barone, Vincenzo; Tarczay, György

    2018-01-01

    The conformers of α-serine were investigated by matrix-isolation IR spectroscopy combined with NIR laser irradiation. This method, aided by 2D correlation analysis, enabled unambiguously grouping the spectral lines to individual conformers. On the basis of comparison of at least nine experimentally observed vibrational transitions of each conformer with empirically scaled (SQM) and anharmonic (GVPT2) computed IR spectra, 6 conformers were identified. In addition, the presence of at least one more conformer in Ar matrix was proved, and a short-lived conformer with a half-live of (3.7±0.5)·103 s in N2 matrix was generated by NIR irradiation. The analysis of the NIR laser induced conversions revealed that the excitation of the stretching overtone of both the side-chain and the carboxylic OH groups can effectively promote conformational changes, but remarkably different paths were observed for the two kinds of excitations. PMID:26201050

  4. Sensitivity of gas filter correlation instrument to variations in optical balance. [computer program simulated the response of the GFCR to changing pollutant levels

    Science.gov (United States)

    Orr, H. D., III; Campbell, S. A.

    1975-01-01

    A computer program was used to simulate the response of the Gas Filter Correlation Radiometer (GFCR) to changing pollutant levels of CO, SO2, CH4, and NH3 in two model atmospheres. Positive and negative deviations of tau sub alpha of magnitudes 0.01, 0.1, and 1 percent were imposed upon the simulation and the resulting deviations in inferred concentrations were determined. For the CO, CH4, and the higher pressure cell of the NH3 channel, the deviations are less than + or - 12 percent for deviations in tau sub alpha of + or - 0.1 percent, but increase to significantly higher values for larger deviations. For the lower pressure cell of NH3 and for SO2, the deviations in inferred concentration begin to rise sharply between 0.01 and 0.1 percent deviation in tau sub alpha, suggesting that a tighter control on tau sub alpha may be required for these channels.

  5. Open access

    NARCIS (Netherlands)

    Valkenburg, P.M.

    2015-01-01

    Open access week Van 19 tot en met 25 oktober 2015 vond wereldwijd de Open Access Week plaats. Tijdens deze week werden er over de hele wereld evenementen georganiseerd waar open access een rol speelt. Ook in Nederland zijn er diverse symposia, workshops en debatten georganiseerd zoals het debat in

  6. Halo sign nodules in angio invasive pulmonary aspergillosis: correlation of high-resolution computed tomography findings with anatomopathology; Nodulos com sinal do halo na aspergilose pulmonar angioinvasiva: correlacao da tomografia computadorizada de alta resolucao com a anatomopatologia

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Radiologia; Valiante, Paulo Marcos [Universidade Federal, Rio de Janeiro, RJ (Brazil). Dept. de Patologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Disciplina de Radiologia

    2002-08-01

    The aim of this study was to correlate the early findings observed on high-resolution computed tomography with anatomopathology results of patients with angio invasive aspergillosis. The authors studied two patients with leukemia. The nodules seen on high-resolution computed tomography corresponded to areas of hemorrhagic infarction, necrotic coagulation and fungal hyphae infiltration whereas ground glass halo corresponded to intra alveolar hemorrhage. Nodules with halo sign were closely correlated with anatomopathology findings. We concluded that the anatomopathology findings can clearly explain the image features of the lesions observed on high-resolution computed tomography. (author)

  7. Adjunctive Steps for Disinfection of the Mandibular Molar Root Canal System: A Correlative Bacteriologic, Micro-Computed Tomography, and Cryopulverization Approach.

    Science.gov (United States)

    Alves, Flávio R F; Andrade-Junior, Carlos V; Marceliano-Alves, Marília F; Pérez, Alejandro R; Rôças, Isabela N; Versiani, Marco A; Sousa-Neto, Manoel D; Provenzano, José C; Siqueira, José F

    2016-11-01

    This study evaluated the disinfecting ability of chemomechanical preparation with rotary nickel-titanium instruments, followed by 2 distinct adjunctive procedures in the root canals of extracted mandibular molars by means of a correlative analytical approach. Twenty-two extracted mandibular molars were selected and anatomically matched between groups on the basis of micro-computed tomographic analysis. In the first phase of the experiment, root canals were contaminated with Enterococcus faecalis and subjected to chemomechanical preparation with BT RaCe instruments and 2.5% NaOCl irrigation. Then either XP-Endo Finisher instrument or passive ultrasonic irrigation was used to supplement disinfection. Micro-computed tomography was used to show whether the percentage of unprepared areas correlated to bacterial counts. In the second phase, the same teeth were contaminated once again, and the adjunctive procedures were used. Samples from the isthmus area of mesial roots and the apical 5-mm fragment of distal roots were obtained by cryopulverization. Samples taken before and after treatment steps in both phases were evaluated by quantitative polymerase chain reaction and statistically analyzed. In phase 1, preparation in both groups resulted in substantial decrease of bacterial counts (P  .05). In phase 2, both methods had significant antibacterial effects in the main canal, but none of them could predictably disinfect the isthmus/recess areas. Both XP-Endo Finisher and passive ultrasonic irrigation exhibited antibacterial effectiveness, but only the former caused a significant reduction in the bacterial counts after chemomechanical preparation. None of them were effective in predictably disinfecting the isthmus/recess areas. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Computational modeling and in-vitro/in-silico correlation of phospholipid-based prodrugs for targeted drug delivery in inflammatory bowel disease

    Science.gov (United States)

    Dahan, Arik; Markovic, Milica; Keinan, Shahar; Kurnikov, Igor; Aponick, Aaron; Zimmermann, Ellen M.; Ben-Shabat, Shimon

    2017-11-01

    Targeting drugs to the inflamed intestinal tissue(s) represents a major advancement in the treatment of inflammatory bowel disease (IBD). In this work we present a powerful in-silico modeling approach to guide the molecular design of novel prodrugs targeting the enzyme PLA2, which is overexpressed in the inflamed tissues of IBD patients. The prodrug consists of the drug moiety bound to the sn-2 position of phospholipid (PL) through a carbonic linker, aiming to allow PLA2 to release the free drug. The linker length dictates the affinity of the PL-drug conjugate to PLA2, and the optimal linker will enable maximal PLA2-mediated activation. Thermodynamic integration and Weighted Histogram Analysis Method (WHAM)/Umbrella Sampling method were used to compute the changes in PLA2 transition state binding free energy of the prodrug molecule (ΔΔGtr) associated with decreasing/increasing linker length. The simulations revealed that 6-carbons linker is the optimal one, whereas shorter or longer linkers resulted in decreased PLA2-mediated activation. These in-silico results were shown to be in excellent correlation with experimental in-vitro data. Overall, this modern computational approach enables optimization of the molecular design of novel prodrugs, which may allow targeting the free drug specifically to the diseased intestinal tissue of IBD patients.

  9. Angiographic patterns of in-stent restenosis classified by computed tomography in patients with drug-eluting stents: correlation with invasive coronary angiography

    International Nuclear Information System (INIS)

    Pan, Jingwei; Lu, Zhigang; Wei, Meng; Zhang, Jiayin; Li, Minghua

    2013-01-01

    To evaluate the diagnostic accuracy of Mehran's in-stent restenosis (ISR) classification by coronary computed angiography (CCTA), with reference to invasive coronary angiography (ICA). Consecutive symptomatic patients, who had clinically suspected ISR and implanted stent diameter ≥ 3 mm, were prospectively enrolled in our study. Mehran's classification was employed by CCTA and ICA to classify ISR lesions into four subtypes: focal, diffuse intrastent, diffuse proliferative and total occlusion. CCTA and ICA measurement of lesion length was further compared. Sixty-one patients with 101 implanted stents were included in our study. The overall sensitivity, specificity, PPV and NPV of CCTA diagnosis of binary ISR, as shown by patient-based analysis (n = 61), were 100 % (49/49), 75 % (8/12), 92.45 % (49/53) and 100 % (8/8) respectively. Mehran's classification of CCTA correlated well with ICA findings. The diagnostic accuracy of CCTA for class I, class II, class III and class IV lesions was 92.5 %, 91.67 %, 100 % and 100 % respectively. Lesion length was assessed to be significantly longer with CCTA than with ICA (11.03 ± 5.89 mm versus 8.56 ± 4.99 mm, P < 0.001). Angiographic patterns of in-stent restenosis can be accurately classified by coronary computed angiography. The lesion length measured by CCTA is longer than that assessed by invasive coronary angiography. (orig.)

  10. Usefulness of measurement of circulation time using MgSO4 : correlation with time-density curve using electron beam computed tomography

    International Nuclear Information System (INIS)

    Kim, Byung Ki; Lee, Hui Joong; Lee, Jong Min; Kim, Yong Joo; Kang, Duck Sik

    1999-01-01

    To determine the usefulness of MgSO 4 for measuring the systemic circulation time. Systemic circulation time, defined as elapsed time from the injection of MgSO 4 solution to the point of pharyngeal burning sensation, was measured in 63 volunteers. MgSO 4 was injected into a superficial vein of an upper extremity. Using dynamic electron beam computed tomography at the level of the abdominal aorta and celiac axis, a time-intensity curve was plotted, and for these two locations, maximal enhancement time was compared. For 60 of the 63 subjects, both systemic circulation time and maximal enhancement time were determined. Average systemic circulation time was 17.4 (SD:3.6) secs. and average maximal enhancement times at the level of the abdominal aorta and celiac axis were 17.5 (SD:3.0) secs. and 18.5 (SD:3.2) secs., respectively. Correlation coefficients between systemic circulation time and maximal enhancement time for the abdominal aorta and celiac axis were 0.73 (p 4 injection and maximal enhancement time for the abdominal aorta showed significant correlation. Thus, to determine the appropriate scanning time in contrast-enhanced radiological studies, MgSO 4 can be used instead of a test bolus study

  11. Thallium-201 single photon emission computed tomography (SPECT) in patients with Duchenne's progressive muscular dystrophy. A histopathologic correlation study

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Toru; Yanagisawa, Atsuo; Sakata, Konomi; Shimoyama, Katsuya; Yoshino, Hideaki; Ishikawa, Kyozo [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine; Sakata, Hitomi; Ishihara, Tadayuki

    2001-02-01

    The pathomorphologic mechanism responsible for abnormal perfusion imaging during thallium-201 myocardial single photon emission computed tomography ({sup 201}Tl-SPECT) in patients with Duchenne's progressive muscular dystrophy (DMD) was investigated. Hearts from 7 patients with DMD were evaluated histopathologically at autopsy and the results correlated with findings on initial and delayed resting {sup 201}Tl-SPECT images. The location of segments with perfusion defects correlated with the histopathologically abnormal segments in the hearts. Both the extent and degree of myocardial fibrosis were severe, especially in the posterolateral segment of the left ventricle. Severe transmural fibrosis and severe fatty infiltration were common in segments with perfusion defects. In areas of redistribution, the degree of fibrosis appeared to be greater than in areas of normal perfusion; and intermuscular edema was prominent. Thus, the degree and extent of perfusion defects detected by {sup 201}Tl-SPECT were compatible with the histopathology. The presence of the redistribution phenomenon may indicate ongoing fibrosis. Initial and delayed resting {sup 201}Tl-SPECT images can predict the site and progress of myocardial degeneration in patients with DMD. (author)

  12. Humidifier disinfectant-associated children's interstitial lung disease: Computed tomographic features, histopathologic correlation and comparison between survivors and non-survivors

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hee Mang; Lee, Jin Seong; Do, Kyung-Hyun; Jung, Ah Young; Yoon, Chong Hyun; Cho, Young Ah [Asan Medical Center, University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Songpa-gu, Seoul (Korea, Republic of); Lee, Eun; Hong, Soo-Jong [Asan Medical Center, University of Ulsan College of Medicine, Department of Pediatrics, Songpa-gu, Seoul (Korea, Republic of); Kim, Seon-Ok [Asan Medical Center, University of Ulsan College of Medicine, Department of Clinical Epidemiology and Biostatistics, Songpa-gu, Seoul (Korea, Republic of); Jang, Se-Jin [Asan Medical Center, University of Ulsan College of Medicine, Departments of Pathology, Songpa-gu, Seoul (Korea, Republic of)

    2016-01-15

    To report radiologic findings with histopathologic correlations of humidifier disinfectant-associated children's interstitial lung disease (HD-chILD) and to compare computed tomography (CT) findings between survivors and non-survivors. Forty-seven children with HD-chILD (27.4 ± 12.4 months old) were categorized as survivors (n = 25) and non-survivors (n = 22). The patterns, distributions, and chronological changes in lung lesions at follow-up CT were investigated. Histopathologic correlations were performed in 23 patients. CT features were characterized by chronological changes, from consolidation to centrilobular opacities, and lesions eventually became faint centrilobular nodules. Histopathologic features were bronchocentric-distributed fibro-inflammatory lesions, which were more profound in the advanced stage than the early stage. Consolidation ≥30 % [hazard ratio (HR), 2.932], centrilobular opacities ≥60 % of the total lung volume (TLV; HR, 0.206) and spontaneous air leaks (HR, 3.457) were significant factors associated with patient survival, as per univariate analysis. Consolidation ≥30 % (HR, 3.519), centrilobular opacities ≥60 % (HR, 0.205) and diffuse ground glass opacity (GGO) ≥70 % of the TLV (HR, 3.521) were significant factors associated with patient survival, as determined via multivariate analysis. Distinctive chronological CT features were observed in the HD-chILD images. Spontaneous air leaks, consolidation, GGO, and centrilobular opacities were prognostic factors. (orig.)

  13. Rheumatoid arthritis-associated interstitial lung disease: lung inflammation evaluated with high resolution computed tomography scan is correlated to rheumatoid arthritis disease activity.

    Science.gov (United States)

    Pérez-Dórame, Renzo; Mejía, Mayra; Mateos-Toledo, Heidegger; Rojas-Serrano, Jorge

    2015-01-01

    To describe the association between rheumatoid arthritis disease activity (RA) and interstitial lung damage (inflammation and fibrosis), in a group of patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD). A retrospective study of RA patients with interstitial lung disease (restrictive pattern in lung function tests and evidence of interstitial lung disease in high resolution computed tomography (HRCT)). Patients were evaluated to exclude other causes of pulmonary disease. RA disease activity was measured with the CDAI index. Interstitial lung inflammation and fibrosis were determined by Kazerooni scale. We compared Kazerooni ground-glass score with the nearest CDAI score to HRCT date scan of the first medical evaluation at our institution. In nine patients, we compared the first ground-glass score with a second one after treatment with DMARDs and corticosteroids. Spearman's rank correlation coefficient was used to evaluate association between RA disease activity and the Kazerooni ground-glass and fibrosis scores. Thirty-four patients were included. A positive correlation between CDAI and ground-glass scores was found (rs=0.3767, P<0.028). Fibrosis and CDAI scores were not associated (rs=-0.0747, P<0.6745). After treatment, a downward tendency in the ground-glass score was observed (median [IQR]): (2.33 [2,3] vs. 2 [1.33-2.16]), P<0.056, along with a lesser CDAI score (27 [8-43] vs. 9 [5-12]), P<0.063. There is a correlation between RA disease activity and ground-glass appearance in the HRCT of RA-ILD patients. These results suggest a positive association between RA disease activity and lung inflammation in RA-ILD. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

  14. The development of remote teaching laboratory access software for multi-slice computed optical tomography for use in undergraduate nuclear education

    Energy Technology Data Exchange (ETDEWEB)

    Price, T.J.; Nichita, E., E-mail: Terry.Price@gmail.com [Univ. of Ontario Inst. of Technology, Oshawa, Ontario (Canada)

    2013-07-01

    Internet-based laboratory exercises were developed for a course on biomedical imaging at the University of Ontario Institute of Technology. These exercises used a multi-slice computed optical tomography machine named DeskCAT to instruct students on the principals of computed tomography. User management software was developed which enabled course instructors to quickly set up a computer to accept a series of scheduled remote user connections for a classroom. Laboratory exercises using the DeskCAT machine were developed to be conducted remotely. (author)

  15. The development of remote teaching laboratory access software for multi-slice computed optical tomography for use in undergraduate nuclear education

    International Nuclear Information System (INIS)

    Price, T.J.; Nichita, E.

    2013-01-01

    Internet-based laboratory exercises were developed for a course on biomedical imaging at the University of Ontario Institute of Technology. These exercises used a multi-slice computed optical tomography machine named DeskCAT to instruct students on the principals of computed tomography. User management software was developed which enabled course instructors to quickly set up a computer to accept a series of scheduled remote user connections for a classroom. Laboratory exercises using the DeskCAT machine were developed to be conducted remotely. (author)

  16. Computer-assisted three-dimensional correlation between the femoral neck-shaft angle and the optimal entry point for antegrade nailing.

    Science.gov (United States)

    Anastopoulos, George; Chissas, Dionisios; Dourountakis, Joseph; Ntagiopoulos, Panagiotis G; Magnisalis, Evaggelos; Asimakopoulos, Antonios; Xenakis, Theodore A

    2010-03-01

    Optimal entry point for antegrade femoral intramedullary nailing (IMN) remains controversial in the current medical literature. The definition of an ideal entry point for femoral IMN would implicate a tenseless introduction of the implant into the canal with anatomical alignment of the bone fragments. This study was undertaken in order to investigate possible existing relationships between the true 3D geometric parameters of the femur and the location of the optimum entry point. A sample population of 22 cadaveric femurs was used (mean age=51.09+/-14.82 years). Computed-tomography sections every 0.5mm for the entire length of femurs were produced. These sections were subsequently reconstructed to generate solid computer models of the external anatomy and medullary canal of each femur. Solid models of all femurs were subjected to a series of geometrical manipulations and computations using standard computer-aided-design tools. In the sagittal plane, the optimum entry point always lied a few millimeters behind the femoral neck axis (mean=3.5+/-1.5mm). In the coronal plane the optimum entry point lied at a location dependent on the femoral neck-shaft angle. Linear regression on the data showed that the optimal entry point is clearly correlated to the true 3D femoral neck-shaft angle (R(2)=0.7310) and the projected femoral neck-shaft angle (R(2)=0.6289). Anatomical parameters of the proximal femur, such as the varus-valgus angulation, are key factors in the determination of optimal entry point for nailing. The clinical relevance of the results is that in varus hips (neck-shaft angle shaft angle between 120 degrees and 130 degrees , the optimal entry point lies just medially to the trochanter tip (at the piriformis fossa) and the use of stiff implants is safe. In hips with neck-shaft angle over 130 degrees the anatomical axis of the canal is medially to the base of the neck, in a "restricted area". In these cases the entry point should be located at the insertion of the

  17. Correlation between Standardized Uptake Value of 68Ga-DOTA-NOC Positron Emission Tomography/Computed Tomography and Pathological Classification of Neuroendocrine Tumors.

    Science.gov (United States)

    Kaewput, Chalermrat; Suppiah, Subapriya; Vinjamuri, Sobhan

    2018-01-01

    The aim of our study was to correlate tumor uptake of 68 Ga-DOTA-NOC positron emission tomography/computed tomography (PET/CT) with the pathological grade of neuroendocrine tumors (NETs). 68 Ga-DOTA-NOC PET/CT examinations in 41 patients with histopathologically proven NETs were included in the study. Maximum standardized uptake value (SUV max ) and averaged SUV SUV mean of "main tumor lesions" were calculated for quantitative analyses after background subtraction. Uptake on main tumor lesions was compared and correlated with the tumor histological grade based on Ki-67 index and pathological differentiation. Classification was performed into three grades according to Ki-67 levels; low grade: Ki-67 20. Pathological differentiation was graded into well- and poorly differentiated groups. The values were compared and evaluated for correlation and agreement between the two parameters was performed. Our study revealed negatively fair agreement between SUV max of tumor and Ki-67 index ( r = -0.241) and negatively poor agreement between SUV mean of tumor and Ki-67 index ( r = -0.094). SUV max of low-grade, intermediate-grade, and high-grade Ki-67 index is 26.18 ± 14.56, 30.71 ± 24.44, and 6.60 ± 4.59, respectively. Meanwhile, SUV mean of low-grade, intermediate-grade, and high-grade Ki-67 is 8.92 ± 7.15, 9.09 ± 5.18, and 3.00 ± 1.38, respectively. As expected, there was statistically significant decreased SUV max and SUV mean in high-grade tumors (poorly differentiated NETs) as compared with low- and intermediate-grade tumors (well-differentiated NETs). SUV of 68 Ga-DOTA-NOC PET/CT is not correlated with histological grade of NETs. However, there was statistically significant decreased tumor uptake of 68 Ga-DOTA-NOC in poorly differentiated NETs as compared with the well-differentiated group. As a result of this pilot study, we confirm that the lower tumor uptake of 68 Ga-DOTA-NOC may be associated with aggressive behavior and may, therefore, result in poor prognosis.

  18. Inconsistency in 9 mm bullets: correlation of jacket thickness to post-impact geometry measured with non-destructive X-ray computed tomography.

    Science.gov (United States)

    Thornby, John; Landheer, Dirk; Williams, Tim; Barnes-Warden, Jane; Fenne, Paul; Norman, Danielle G; Attridge, Alex; Williams, Mark A

    2014-01-01

    Fundamental to any ballistic armour standard is the reference projectile to be defeated. Typically, for certification purposes, a consistent and symmetrical bullet geometry is assumed, however variations in bullet jacket dimensions can have far reaching consequences. Traditionally, characteristics and internal dimensions have been analysed by physically sectioning bullets--an approach which is of restricted scope and which precludes subsequent ballistic assessment. The use of a non-destructive X-ray computed tomography (CT) method has been demonstrated and validated (Kumar et al., 2011 [15]); the authors now apply this technique to correlate bullet impact response with jacket thickness variations. A set of 20 bullets (9 mm DM11) were selected for comparison and an image-based analysis method was employed to map jacket thickness and determine the centre of gravity of each specimen. Both intra- and inter-bullet variations were investigated, with thickness variations of the order of 200 μm commonly found along the length of all bullets and angular variations of up to 50 μm in some. The bullets were subsequently impacted against a rigid flat plate under controlled conditions (observed on a high-speed video camera) and the resulting deformed projectiles were re-analysed. The results of the experiments demonstrate a marked difference in ballistic performance between bullets from different manufacturers and an asymmetric thinning of the jacket is observed in regions of pre-impact weakness. The conclusions are relevant for future soft armour standards and provide important quantitative data for numerical model correlation and development. The implications of the findings of the work on the reliability and repeatability of the industry standard V50 ballistic test are also discussed. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. Retrospective analysis of a Computer-Aided Detection (CAD) system in full-field digital mammography in correlation to tumor histology

    International Nuclear Information System (INIS)

    Obenauer, S.; Sohns, C.; Grabbe, E.; Werner, C.

    2005-01-01

    Purpose: to evaluate the usefulness of a computer-aided detection (CAD) system in full-field digital mammography in correlation to tumor histology. Material and methods: a total of 476 patients (226 patients with histologically proven malignant tumors, 250 healthy women) took part in this study. The mammograms were studied retrospectively, using the CAD system Image Checker. For 226 patients digital mammograms in MLO-projection were available. For 186 of these patients the CC-projection was also available. CAD markers that correlated with histologically proven carcinomas were considered to be true-positive markers. All other CAD markers were considered to be false-positive. Histologically proven carcinomas without markers were false-negative results. The dependence of the CAD markers placement upon the different carcinoma histologies was studied using the Chi-square test. Results: no significant difference could be proven for the detectability of malignant breast lesions of different histologic types. For the detectability of ductal carcinoma in situ (DCIS), invasive ductal carcinoma (IDC), invasive lobular carcinoma (ILC), lobular carcinoma in situ (LCIS), tubular carcinoma and ductulo-lobular carcinoma, the true positives were 71.1%, 75%, 70.7%, 70%, 60% and 80%, respectively, in the MLO projection and 83.9%, 75.9%, 81.8%, 77.8%, 87.5% and 33.3%, respectively, in the CC projection. There was an average of 0.5 false-positive markers per mammographic image. Conclusion: The histologic type of carcinoma seems to have no influence on detectability when using the CAD system. The high rate of false-positive markers shows, however, the limited specificity of the CAD system and that improvements are necessary. (orig.)

  20. Open Access

    Science.gov (United States)

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder…

  1. Open access

    African Journals Online (AJOL)

    Prof. Dennis Ocholla

    The argument that access to information is an instrumental and individual as well as ... and Dean School of Information Studies, University of Wisconsin, Milwaukee, USA. ... to scholarly publications and can be in any digital format, including text, movies and ... language barriers, censorship, lack of access to the Internet and ...

  2. Living with Computers. Young Danes' Uses of and Thoughts on the Uses of Computers

    DEFF Research Database (Denmark)

    Stald, Gitte Bang

    1998-01-01

    Young Danes, computers,users, super users, non users, computer access, unge danskere, computere,brugere,superbrugere,ikke-brugere......Young Danes, computers,users, super users, non users, computer access, unge danskere, computere,brugere,superbrugere,ikke-brugere...

  3. Variability in the range of inter-anterior superior iliac spine distance and its correlation with femoral head centre. A prospective computed tomography study of 200 adults

    International Nuclear Information System (INIS)

    Mullaji, Arun; Shetty, Gautam M.; Kanna, Raj; Sharma, Amit

    2010-01-01

    The anterior superior iliac spine (ASIS) is commonly used to estimate the centre of the femoral head and assess limb alignment during surgical procedures. This study aimed to determine the range of inter-anterior superior iliac spine distances (IADs) and inter-femoral head centre distances (IFDs) among individuals and ascertain whether there is correlation between the IFD and the IAD. We also sought to determine whether gender, height and body mass index (BMI) had any influence on IAD and IFD. We prospectively measured IAD and IFD in 200 adults, using transverse computed tomography (CT) scans done for medical causes. We also calculated the distance between the pelvic midline and the centre of the femoral head (XY distance) from the measured IFD. The influence of gender, height and body-mass index on IAD and IFD, and the correlation of IAD with IFD, were also studied. The overall mean IAD, IFD and XY distances were 22.7 ± 1.6 cm, 16.0 ± 0.8 cm and 8.0 ± 0.4 cm, respectively. There was wide variation within the IAD range with 50% (100/200) of the subjects having their IAD within ±10 mm of the mean compared to 75.5% (151/200) of the subjects with IFD within ±10 mm of the mean. The probability that the mean XY distance would fall within 10 mm of the true femoral head centre in all subjects was 100%. The gender difference in IAD and IFD was statistically significant (P = 0.03 and P < 0.001, respectively), height and BMI had no influence, and the correlation of IAD with IFD was weak (0.35). Although the range of IADs showed wide variation among subjects, this study clearly demonstrated the narrow range of the XY distance and IFD in the study population and provides a useful and accurate basis for a new method to determine the femoral head centre clinically and intraoperatively. (orig.)

  4. An analysis of peripheral small lung carcinomas less than 20 mm in diameter in non-adenocarcinomas and carcinoids. Computed tomographic findings based on radiologic-pathologic correlation

    International Nuclear Information System (INIS)

    Tanaka, Gaku; Yamada, Kouzo; Oshita, Fumihiro; Nomura, Ikuo; Noda, Kazumasa; Nakayama, Haruhiko; Mitsuda, Aki; Kameda, Youichi; Yamakido, Michio

    2000-01-01

    With the introduction of computed tomography (CT) for chest screening in recent years, more cases of resected peripheral small lung carcinomas have been reported. Many of these were adenocarcinomas. To focus on CT findings of peripheral non-adenocarcinoma nodules, we performed a retrospective analysis based on radiographic-pathologic correlations. We analyzed CT findings based on the pathology of peripheral small lung carcinomas, excluding the histological type of adenocarcinomas. We compared our findings with those observed in adenocarcinomas. We reviewed 28 peripheral small lung carcinoma nodules less than 20 mm in diameter, including 13 squamous cell carcinomas, 4 small cell carcinomas, 2 adeno- squamous cell carcinomas, 1 large cell carcinoma, and 8 carcinoids. The carcinomas were classified into two different patterns; non-adenocarcinomas excluding carcinoids, and carcinoids. Both were solid-density types on high-resolution CT (HR-CT) images. The HR-CT findings regarding the shape and number of notching, and the presence or absence of ground glass opacity (GGO) were different between non-adenocarcinomas excluding carcinoids and adenocarcinomas. On the other hand, the HR-CT findings regarding spiculations, GGO and pleural indentations, and the absence of bronchial compression were different between carcinoids and adenocarcinomas. The shape characteristics and internal and marginal analysis on HR-CT images can contribute to the differential diagnosis of the histological type of peripheral small lung carcinomas. (author)

  5. Clinical observations on the effect of carotid artery occlusion on cerebral blood flow mapped by xenon computed tomography and its correlation with carotid artery back pressure

    International Nuclear Information System (INIS)

    Steed, D.L.; Webster, M.W.; DeVries, E.J.; Jungreis, C.A.; Horton, J.A.; Sehkar, L.; Yonas, H.

    1990-01-01

    Xenon computed tomographic cerebral blood flow mapping was correlated with internal carotid artery stump pressures and clinical neurologic assessment during temporary internal carotid artery occlusion. One hundred fourteen patients with skull base tumors or intracranial aneurysms potentially requiring carotid resection or ligation underwent angiography, xenon CT cerebral blood flow mapping, and internal carotid artery blood pressure monitoring. The internal carotid artery was then temporarily occluded with a balloon catheter, stump pressure was measured through the catheter, and the xenon CT cerebral blood flow mapping was repeated. Adequate xenon CT cerebral blood flow was defined as greater than 30 cc/100 gm/min. All patients had normal xenon CT cerebral blood flow before internal carotid artery occlusion. During internal carotid artery occlusion, xenon CT cerebral blood flow was found to be normal (group I, 40 patients), globally reduced but still within the normal range (group II, 50 patients), or low in the distribution of the ipsilateral middle cerebral artery (group III, 13 patients). With balloon occlusion, an immediate neurologic deficit developed in 11 patients (9%) requiring deflation of the balloon preceding xenon CT cerebral blood flow measurement (group IV). In group I internal carotid artery blood pressure was 128 mm Hg. (range 85 to 171 mm Hg) with stump pressure 86 mm Hg (range 46 to 125 mm Hg). In group II internal carotid artery blood pressure was 130 mm Hg. (range 78 to 199 mm Hg), with stump pressure 86 mm Hg (range 31 to 150 mm Hg)

  6. In Depth Analyses of LEDs by a Combination of X-ray Computed Tomography (CT) and Light Microscopy (LM) Correlated with Scanning Electron Microscopy (SEM).

    Science.gov (United States)

    Meyer, Jörg; Thomas, Christian; Tappe, Frank; Ogbazghi, Tekie

    2016-06-16

    In failure analysis, device characterization and reverse engineering of light emitting diodes (LEDs), and similar electronic components of micro-characterization, plays an important role. Commonly, different techniques like X-ray computed tomography (CT), light microscopy (LM) and scanning electron microscopy (SEM) are used separately. Similarly, the results have to be treated for each technique independently. Here a comprehensive study is shown which demonstrates the potentials leveraged by linking CT, LM and SEM. In depth characterization is performed on a white emitting LED, which can be operated throughout all characterization steps. Major advantages are: planned preparation of defined cross sections, correlation of optical properties to structural and compositional information, as well as reliable identification of different functional regions. This results from the breadth of information available from identical regions of interest (ROIs): polarization contrast, bright and dark-field LM images, as well as optical images of the LED cross section in operation. This is supplemented by SEM imaging techniques and micro-analysis using energy dispersive X-ray spectroscopy.

  7. Flexible Access Control for Dynamic Collaborative Environments

    NARCIS (Netherlands)

    Dekker, M.A.C.

    2009-01-01

    Access control is used in computer systems to control access to confidential data. In this thesis we focus on access control for dynamic collaborative environments where multiple users and systems access and exchange data in an ad hoc manner. In such environments it is difficult to protect

  8. Correlation between computer-aided dynamic gadolinium-enhanced MRI assessment of inflammation and semi-quantitative synovitis and bone marrow oedema scores of the wrist in patients with rheumatoid arthritis--a cohort study

    DEFF Research Database (Denmark)

    Boesen, Mikael; Kubassova, Olga; Bouert, Rasmus

    2012-01-01

    Objective. To test the correlation between assessment of inflammation using dynamic contrast-enhanced MRI (DCE-MRI) analysed by a novel computer-aided approach and semi-quantitative scores of synovitis and bone marrow oedema (BME) using the OMERACT-RA MRI Scoring (RAMRIS) system, in the wrist...... extended region of interest (ROI) placed around the wrist joint (semi-automated approach) and (iii) within a small ROI placed in the area with most visual enhancement (semi-automated approach). Time spent on each procedure was noted. Spearman's rank correlation test was applied to assess the correlation...... between RAMRIS and the computer-generated dynamic parameters. Results. RAMRIS synovitis (range 2-9), BME (range 0-39) and the dynamic parameters reflecting the number of enhancing voxels were significantly correlated, especially when an extended ROI around the wrist was used (¿¿=¿0.74; P¿...

  9. Democratizing Computer Science

    Science.gov (United States)

    Margolis, Jane; Goode, Joanna; Ryoo, Jean J.

    2015-01-01

    Computer science programs are too often identified with a narrow stratum of the student population, often white or Asian boys who have access to computers at home. But because computers play such a huge role in our world today, all students can benefit from the study of computer science and the opportunity to build skills related to computing. The…

  10. Access Contested

    International Development Research Centre (IDRC) Digital Library (Canada)

    Transforming Global Information and Communication Markets: The Political Economy of ... 8 Control and Resistance: Attacks on Burmese Opposition Media 153 ...... “Reluctant Gatekeepers: Corporate Ethics on a Filtered Internet,” in Access ...

  11. Accessing memory

    Science.gov (United States)

    Yoon, Doe Hyun; Muralimanohar, Naveen; Chang, Jichuan; Ranganthan, Parthasarathy

    2017-09-26

    A disclosed example method involves performing simultaneous data accesses on at least first and second independently selectable logical sub-ranks to access first data via a wide internal data bus in a memory device. The memory device includes a translation buffer chip, memory chips in independently selectable logical sub-ranks, a narrow external data bus to connect the translation buffer chip to a memory controller, and the wide internal data bus between the translation buffer chip and the memory chips. A data access is performed on only the first independently selectable logical sub-rank to access second data via the wide internal data bus. The example method also involves locating a first portion of the first data, a second portion of the first data, and the second data on the narrow external data bus during separate data transfers.

  12. Forbidden Access

    CERN Multimedia

    C. Colloca TS/FM

    2004-01-01

    TS/FM group informs you that, for the replacement of the door of the main entrance at bldg. 500, the access will be closed to the public between 19 and 30 July 2004. Access to the Main Building complex will be assured at any time through both of the side doors and from bldg. 64. For more information, please contact 73273. C. Colloca TS/FM

  13. Guidelines for Outsourcing Remote Access.

    Science.gov (United States)

    Hassler, Ardoth; Neuman, Michael

    1996-01-01

    Discusses the advantages and disadvantages of outsourcing remote access to campus computer networks and the Internet, focusing on improved service, cost-sharing, partnerships with vendors, supported protocols, bandwidth, scope of access, implementation, support, network security, and pricing. Includes a checklist for a request for proposals on…

  14. Bleomycin-Induced Pulmonary Changes on Restaging Computed Tomography Scans in Two Thirds of Testicular Cancer Patients Show No Correlation With Fibrosis Markers.

    Science.gov (United States)

    den Hollander, Martha W; Westerink, Nico-Derk L; Lubberts, Sjoukje; Bongaerts, Alfons H H; Wolf, Rienhart F E; Altena, Renska; Nuver, Janine; Oosting, Sjoukje F; de Vries, Elisabeth G E; Walenkamp, Anna M E; Meijer, Coby; Gietema, Jourik A

    2016-08-01

    preferable. This study found that bleomycin-induced pulmonary changes are common on restaging computed tomography scans and mostly resolve. No correlation was seen between these changes and fibrosis or inflammation markers (transforming growth factor-β1, growth differentiation factor-15, and high-sensitivity C-reactive protein). ©AlphaMed Press.

  15. Correlation of Tc-99 m ethyl cysteinate dimer single-photon emission computed tomography and clinical presentations in patients with low cobalamin status.

    Science.gov (United States)

    Tu, Min-Chien; Lo, Chung-Ping; Chen, Ching-Yuan; Huang, Ching-Feng

    2015-12-03

    Cobalamin (Cbl) deficiency has been associated with various neuropsychiatric symptoms of different severities. While some studies dedicated in structural neuroimaging credibly address negative impact of low Cbl status, functional imaging reports are limited. We herein retrospectively review the correlation of Tc-99 m ethyl cysteinate dimer single-photon emission computed tomography (Tc-99 m-ECD SPECT) and clinical presentations among patients with low serum cobalamin (Cbl) status (Tc-99 m-ECD SPECT, and neuropsychological tests were reviewed. Dysexecutive syndrome (67 %), forgetfulness (50 %), attention deficits (42 %), and sleep disorders (33 %) constituted the major clinical presentations. All patients (100 %) had temporal hypoperfusion on the Tc-99 m-ECD SPECT. Five patients (42 %) had hypoperfusion restricted within temporal regions and deep nuclei; seven patients (58 %) had additional frontal hypoperfusion. In patients with hypoperfusion restricted within temporal regions and deep nuclei, psychiatric symptoms with spared cognition were their main presentations. Among patients with additional frontal hypoperfusion, six of seven patients (86 %) showed impaired cognitive performances (two of them were diagnosed as having dementia). Among ten patients who finished neuropsychological tests, abstract thinking (70 %) was the most commonly affected, followed by verbal fluency (60 %), short-term memory (50 %), and attention (50 %). Anxiety and sleep problems were the major clinically remarkable psychiatric features (33 % both). Four Tc-99 m-ECD SPECT follow-up studies were available; the degree and extent of signal reversal correlated with cognitive changes after Cbl replacement therapy. Our TC-99 m-ECD SPECT observations provide pivotal information of neurobiological changes within basal ganglia and fronto-temporal regions in conjunction with disease severity among patients with Cbl deficiency. Hypoperfusion within thalamus/basal ganglia and temporal regions may be

  16. Complex tibial plateau fractures treated by hybrid external fixation system: A correlation of followup computed tomography derived quality of reduction with clinical results

    Directory of Open Access Journals (Sweden)

    Konstantinos Kateros

    2018-01-01

    Full Text Available Background: Tibial plateau fractures are common due to high energy injuries. The principles of treatment include respect for the soft tissues, restoring the congruity of the articular surface and reduction of the anatomic alignment of the lower limb to enable early movement of the knee joint. There are various surgical fixation methods that can achieve these principles of treatment. Recognition of the particular fracture pattern is important, as this guides the surgical approach required in order to adequately stabilize the fracture. This study evaluates the results of the combined treatment of external fixator and limited internal fixation along with the advantages using postoperative computed tomography (CT scan after implant removal. Materials and Methods: 55 patients with a mean age of 42 years (range 17–65 years with tibial plateau fracture, were managed in our institution between October 2010 and September 2013., Twenty fractures were classified as Schatzker VI and 35 as Schatzker V. There were 8 open fractures (2 Gustilo Anderson 3A and 6 Gustilo Anderson 2. All fractures were treated with closed reduction and hybrid external fixation (n = 21/38.2% or with minimal open reduction internal fixation and a hybrid system (n = 34/61.8%. After the removal of the fixators, CT-scan was programmed for all the cases, for correlation with the results. At final followup, the American Knee Society Score (AKSS was administered. Results: All patients were evaluated with a minimum of 12 months (range 12–21 months followup. Average time to union was 15.5 weeks (range 13–19 weeks. The postoperative joint congruity as evaluated in the postoperative CT-scan was 5° in 19 cases (35%. Patients with residual joint depression 4.5 mm displayed a 100% chance of getting poor-fair scores both in AKSS knee and AKSS function score. The association of a postoperative mechanical axis within 5° of the contralateral limb and improved knee scores was statistically

  17. Correlation of angina pectoris and perfusion decrease by collateral circulation in single-vessel coronary chronic total occlusion using myocardial perfusion single-photon emssion computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Sang Geon; Park, Ki Seong; Kang, Sae Ryung [Chonnam National University Hospital, Gwangju (Korea, Republic of); and others

    2016-03-15

    To evaluate the perfusion decrease in donor myocardium by collateral circulation and its correlation with angina pectoris in patients with chronic total occlusion (CTO) using myocardial perfusion single-photon emission computed tomography (MPS). Thirty-six patients with single-vessel CTO without any other stenosis were included. All patients underwent MPS and coronary angiography (CAG) within 2 months. Total 72 donor arteries were evaluated for the grades of collaterals to the CTO artery using the Rentrop grading system on CAG. Perfusion defects and perfusion scores in donor and CTO territories were analyzed on MPS. Myocardial perfusion of donor and CTO territories were evaluated according to the presence of angina pectoris and the grades of collateral circulation. When the CTO territory was ischemic, symptomatic patients showed higher summed difference scores in the CTO territory compared to asymptomatic patients (3.5 ± 2.4 vs. 1.5 ± 0.8 for symptomatic and asymptomatic groups respectively; p = 0.034). However, when the CTO territory was nonischemic, symptomatic patients showed higher summed stress scores (SSS, 4.3 ± 2.9 vs. 1.6 ± 1.2; p = 0.032) and summed rest scores (SRS, 4.2 ± 2.5 vs. 1.5 ± 1.1; p = 0.003) in the donor territories. On the per-vessel analysis, perfusion defects in donor territories were more frequent (0 % vs. 53 % vs. 86 % for Rentrop 0, Rentrop 1–2 and Rentrop 3, respectively; p < 0.001) and showed higher SSS (0.0 ± 0.0, 1.3 ± 1.6 and 2.1 ± 1.1 for Rentrop 0, Rentrop 1–2 and Rentrop 3, respectively; p = 0.001) and SRS (0.0 ± 0.0, 1.0 ± 1.4 and 1.7 ± 1.2; p = 0.003) at higher Rentrop grades, but their patterns were variable. Angina pectoris was related to either ischemia of the myocardium beyond CTO or a perfusion decrease in the donor myocardium. The perfusion decrease in donor myocardium positively correlated with the collateral grades.

  18. Quantitative perfusion computed tomography measurements of cerebral hemodynamics: Correlation with digital subtraction angiography identified primary and secondary cerebral collaterals in internal carotid artery occlusive disease

    International Nuclear Information System (INIS)

    Cheng Xiaoqing; Tian Jianming; Zuo Changjing; Liu Jia; Zhang Qi; Lu Guangming

    2012-01-01

    Background: The aim of the present study was to assess hemodynamic variations in symptomatic unilateral internal carotid artery occlusion (ICAO) patients with primary collateral flow via circle of Willis or secondary collateral flow via ophthalmic artery and/or leptomeningeal collaterals. Methods: Thirty-eight patients with a symptomatic unilateral ICAO were enrolled in the study. Based on digital subtraction angiography (DSA) findings, patients were classified into 2 groups: primary collateral (n = 14) and secondary collateral (n = 24) groups. Collateral flow hemodynamics were investigated with perfusion computed tomography (PCT) by measuring the cerebral blood flow (CBF), cerebral blood volume (CBV) and time to peak (TTP) in the hemispheres ipsilateral and contralateral to ICAO. Based on the measurements, the ipsilateral to contralateral ratio for each parameter was calculated and compared. Results: Irrespective of the collateral patterns, ipsilateral CBF was not significantly different from that of the contralateral hemisphere (P = 0.285); ipsilateral CBV and TTP was significantly increased compared with those of the contralateral hemisphere (P = 0.000 and P = 0.000 for CBV and TTP, respectively). Furthermore, patients with secondary collaterals had significantly larger ipsilateral-to-contralateral ratios for both CBV (rCBV, P = 0.0197) and TTP (rTTP, P = 0.000) than those of patients with only primary collaterals. These two groups showed no difference in ipsilateral-to-contralateral ratio for CBF (rCBF, P = 0.312). Conclusion: Patients with symptomatic unilateral ICAO in our study were in an autoregulatory vasodilatation status. Moreover, secondary collaterals in ICAO patients were correlated with ipsilateral CBV and delayed TTP that suggested severe hemodynamic impairment, presumably increasing the risk of ischemic events.

  19. Computed tomographic (CT) study of the brains of 357 elderly demented patients. Clinical usefulness of CT measurements of brain atrophy and its correlation with mental assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kono, Kazuhiko; Endo, Hidetoshi; Yamamoto, Takayuki; Kuzuya, Fumio

    1988-05-01

    It is well known that there is some limitation in the diagnostic effectiveness of brain computed tomography (CT) of dementia. Some investigators suggested certain correlation between brain atrophy and degree of psychological imparement in demented patients, but others did not agree with these suggestions. Authors have felt that the number of samples is very important in statistical analyses, thus they collected a great number of appropriate samples of dementia: that is, 59 of Alzheimer disease (AD), 120 of senile dementia of Alzheimer type (SDAT) and 178 of vascular dementia (VD), and compared these CT findings with those of 100 non-demented people. Firstly, we observed no relation between aging and brain atrophy in any type of dementia while there was a certain relation in non-demented people. Secondly, the female brain could easily become atrophic physiologically and was more severely atrophic in case of dementia compared with the male brain. Thirdly, it was impossible to differentiate SDAT from VD only by measuring values of dilatation of ventricles (maximum width of the third ventricle and cella media index) and sylvian fissures (''sylvian index''). Finally, it was observed that there was deep relation between the results of clinical assessments and the degree of brain atrophy in SDAT, because individual specificity in the type of atrophy was not variable in this type of dementia. Moreover all functions: that is, motor, intellectual, and emotional functions in SDAT patients, were impaired in the same degree respectively. From these results, authors could know many available characteristics of atrophy in the brains of demented patients through the following easy methods of measurement: linear measure method and ventricular-brain method, because we could analyse a sufficient number of samples.

  20. Accessible Knowledge - Knowledge on Accessibility

    DEFF Research Database (Denmark)

    Kirkeby, Inge Mette

    2015-01-01

    Although serious efforts are made internationally and nationally, it is a slow process to make our physical environment accessible. In the actual design process, architects play a major role. But what kinds of knowledge, including research-based knowledge, do practicing architects make use of when...... designing accessible environments? The answer to the question is crucially important since it affects how knowledge is distributed and how accessibility can be ensured. In order to get first-hand knowledge about the design process and the sources from which they gain knowledge, 11 qualitative interviews...... were conducted with architects with experience of designing for accessibility. The analysis draws on two theoretical distinctions. The first is research-based knowledge versus knowledge used by architects. The second is context-independent knowledge versus context-dependent knowledge. The practitioners...

  1. The correlation of symptoms, pulmonary function tests and exercise testing with high-resolution computed tomography in patients with idiopathic interstitial pneumonia in a tertiary care hospital in South India.

    Science.gov (United States)

    Isaac, Barney Thomas Jesudason; Thangakunam, Balamugesh; Cherian, Rekha A; Christopher, Devasahayam Jesudas

    2015-01-01

    For the follow-up of patients with idiopathic interstitial pneumonias (IIP), it is unclear which parameters of pulmonary function tests (PFT) and exercise testing would correlate best with high-resolution computed tomography (HRCT).. To find out the correlation of symptom scores, PFTs and exercise testing with HRCT scoring in patients diagnosed as idiopathic interstitial pneumonia. Cross-sectional study done in pulmonary medicine outpatients department of a tertiary care hospital in South India. Consecutive patients who were diagnosed as IIP by a standard algorithm were included into the study. Cough and dyspnea were graded for severity and duration. Pulmonary function tests and exercise testing parameters were noted. HRCT was scored based on an alveolar score, an interstitial score and a total score. The HRCT was correlated with each of the clinical and physiologic parameters. Pearson's/Spearman's correlation coefficient was used for the correlation of symptoms and parameters of ABG, PFT and 6MWT with the HRCT scores. A total of 94 patients were included in the study. Cough and dyspnea severity (r = 0.336 and 0.299), FVC (r = -0.48), TLC (r = -0.439) and DLCO and distance saturation product (DSP) (r = -0.368) and lowest saturation (r = -0.324) had significant correlation with total HRCT score. Among these, DLCO, particularly DLCO corrected % of predicted, correlated best with HRCT score (r = -0.721).. Symptoms, PFT and exercise testing had good correlation with HRCT. DLCO corrected % of predicted correlated best with HRCT.

  2. Open access

    CERN Document Server

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder consent, and many authors, musicians, filmmakers, and other creators who depend on royalties are understandably unwilling to give their consent. But for 350 years, scholars have written peer-reviewed journal articles for impact, not for money, and are free to consent to open access without losing revenue. In this concise introduction, Peter Suber tells us what open access is and isn't, how it benefits authors and readers of research, how we pay for it, how it avoids copyright problems, how it has moved from the periphery to the mainstream, and what its future may hold. Distilling a decade of Suber's influential writing and thinking about open access, this is the indispe...

  3. Access French

    CERN Document Server

    Grosz, Bernard

    2014-01-01

    Access is the major new language series designed with the needs of today's generation of students firmly in mind. Whether learning for leisure or business purposes or working towards a curriculum qualification, Access French is specially designed for adults of all ages and gives students a thorough grounding in all the skills required to understand, speak, read and write contemporary French from scratch. The coursebook consists of 10 units covering different topic areas, each of which includes Language Focus panels explaining the structures covered and a comprehensive glossary. Learning tips

  4. Telecommunication access to INIS

    International Nuclear Information System (INIS)

    Scheel, H.; Breitfeld, B.; Huebner, B.

    1983-01-01

    Proceeding from the features of on-line retrieval from the INIS data base, a description is given of the technical and organizational conditions established by the national INIS Centre of the GDR in using the INIS direct access service. Data are presented on the structure of search queries, retrieval precision, and connect time to the computer. Experience has shown that efficient dialogue searching necessitates the searcher's skill and familiarity with the system. (author)

  5. Gaining Access.

    Science.gov (United States)

    Wand, Sean; Thermos, Adam C.

    1998-01-01

    Explains the issues to consider before a college decides to purchase a card-access system. The benefits of automation, questions involving implementation, the criteria for technology selection, what typical card technology involves, privacy concerns, and the placement of card readers are discussed. (GR)

  6. Computers in Academic Architecture Libraries.

    Science.gov (United States)

    Willis, Alfred; And Others

    1992-01-01

    Computers are widely used in architectural research and teaching in U.S. schools of architecture. A survey of libraries serving these schools sought information on the emphasis placed on computers by the architectural curriculum, accessibility of computers to library staff, and accessibility of computers to library patrons. Survey results and…

  7. A correlation study on the displacement of the whole breast target after breast-conserving surgery based on four-dimensional computed tomography

    International Nuclear Information System (INIS)

    Wang Wei; Li Jianbin; Wang Suzhen; Zhang Yingjie; Li Fengxiang; Xu Min; Shang Dongping

    2011-01-01

    Objective: To investigate the correlations of the whole breast displacement in different respiratory cycle during free breathing (FB) following breast-conserving surgery to the displacement of selected skin marker, nipple, and selected surgical clip based on four-dimensional computed tomography (4D-CT). Methods: Thirteen breast cancer patients who had undergone breast-conserving surgery received whole breast intensity-modulated radiotherapy (IMRT). Respiration-synchronized 4D-CT image data were gathered during FB and were exported to the Varian Eclipse treatment planning system, and the whole breast target, nipple, superior clip,and metal marker on the skin at the anterior body midline were delineated on the CT images of ten phases of the respiratory cycle by the same radiotherapist based on the same delineating criteria. The displacement distances of the delineated target in the mediolateral (x), anteroposterior (y), and superoinferior (z) axles were achieved,and the correlations of the whole breast target displacement to the displacement of the clip, nipple, and skin marker were analyzed. The ipsilateral lung was delineated on the CT images of every phase of the respiratory cycle, and the changes in ipsilateral lung volume were analyzed during the respiratory cycle relative to the displacement of the breast. Results: The maximal displacement distances of the whole breast target in the x, y, and z axles during FB were 0.71, 0.76 and 1.29 mm, respectively (F=5.755, P<0.05). There was no relationship between the three-dimensional (3D) displacement of the whole breast and the volume of the whole breast (r=-0.264, P<0.05), and there was no relationship between the displacement of the whole breast and the volume change of the ipsilateral lung (r=0.346, P<0.05). There was no significant difference among the mean target displacement distances in 3 axles,and among 2 selected successive end-inspiration (EI) phases and 3 selected successive end-expiration (EE) phases. There

  8. Remote direct memory access

    Science.gov (United States)

    Archer, Charles J.; Blocksome, Michael A.

    2012-12-11

    Methods, parallel computers, and computer program products are disclosed for remote direct memory access. Embodiments include transmitting, from an origin DMA engine on an origin compute node to a plurality target DMA engines on target compute nodes, a request to send message, the request to send message specifying a data to be transferred from the origin DMA engine to data storage on each target compute node; receiving, by each target DMA engine on each target compute node, the request to send message; preparing, by each target DMA engine, to store data according to the data storage reference and the data length, including assigning a base storage address for the data storage reference; sending, by one or more of the target DMA engines, an acknowledgment message acknowledging that all the target DMA engines are prepared to receive a data transmission from the origin DMA engine; receiving, by the origin DMA engine, the acknowledgement message from the one or more of the target DMA engines; and transferring, by the origin DMA engine, data to data storage on each of the target compute nodes according to the data storage reference using a single direct put operation.

  9. Evaluation of the success rate of cone beam computed tomography in determining the location and direction of screw access holes in cement-retained implant-supported prostheses: An in vitro study.

    Science.gov (United States)

    Neshandar Asli, Hamid; Dalili Kajan, Zahra; Gholizade, Fatemeh

    2018-02-21

    Cement-retained implant-supported restorations have advantages over screw-retained restorations but are difficult to retrieve. Identifying the approximate location of the screw access hole (SAH) may reduce damage to the prosthesis. The purpose of this in vitro study was to evaluate the ability of cone beam computed tomography (CBCT) imaging to determine the location and direction of SAHs in cement-retained implant prostheses. Five clear acrylic resin casts were made based on a mandibular model. Several implant osteotomies (n=30) were created on the models with surgical burs, and crowns were made using the standard laboratory method with a transfer coping and the closed tray impression technique. CBCT images from the acrylic resin casts were evaluated by a maxillofacial radiologist who was blind to the locations and angles of the osteotomies. The locations of the access holes were determined on multiplanar reconstruction images and transferred to the clinical crown surface as defined points. Based on cross-sectional images, the predicted angle of the access hole was provided to a prosthodontist who was requested to pierce the crown at the proposed location in the specified direction. If the location and/or direction of the access hole were found, the process was considered successful, as the crown could then be removed from the implant abutment through the SAH. The success rate in the detection of the location and direction of the SAH was calculated, and chi-square and Fisher exact tests were applied for data analysis (α=.05). According to the results of this study, the success rate of CBCT to define the location of SAHs was 83.3% and 80% to determine the direction. No significant differences were found among the different dental groups in determination of the location (P=.79) or the direction (P=.53) of the SAHs. Most of the failures in determining the location and direction of the access hole in the buccolingual and mesiodistal directions were in the buccal and

  10. Retrospective application of Program to Access and Review Trending iNformation and Evaluate coRrelation to Symptoms in patients with Heart Failure criteria for the remote management of patients with cardiac resynchronisation therapy.

    Science.gov (United States)

    Brasca, Francesco Ma; Franzetti, Jessica; Rella, Valeria; Malfatto, Gabriella; Brambilla, Roberto; Facchini, Mario; Parati, Gianfranco; Perego, Giovanni B

    2017-05-01

    Aim The Program to Access and Review Trending iNformation and Evaluate coRrelation to Symptoms in patients with Heart Failure (PARTNERS HF) trial elaborated a multiparametric model for prediction of acute decompensation in advanced heart failure patients, based on periodical in office data download from cardiac resynchronisation devices. In this study, we evaluated the ability of the PARTNERS HF criteria to detect initial decompensation in a population of moderate heart failure patients under remote monitoring. Methods We retrospectively applied the PARTNERS HF criteria to 1860 transmissions from 104 patients (median follow up 21 months; range 1-67 months), who were enrolled in our programme of telemedicine after cardiac resynchronisation therapy. We tested the ability of a score based on these criteria to predict any acute clinical decompensation occurring in the 15 days following a transmission. Results In 441 cases, acute heart failure was diagnosed after the index transmission. The area under the curve (AUC) of the score for the diagnosis of acute decompensation was 0.752 (confidence interval (CI) 95% 0.728-0.777). The best score cut-off was consistent with the results of PARTNERS HF: with a score ≥2, sensitivity was 75% and specificity 68%. The odds ratio for events was 6.24 (CI 95% 4.90-7.95; p < 0.001). Conclusions When retrospectively applied to remote monitoring transmissions and arranged in a score, PARTNERS HF criteria could identify HF patients who subsequently developed acute decompensation. These results warrant prospective studies applying PARTNERS HF criteria to remote monitoring.

  11. Correlation of 3D Shift and 3D Tilt of the Patella in Patients With Recurrent Dislocation of the Patella and Healthy Volunteers: An In Vivo Analysis Based on 3-Dimensional Computer Models.

    Science.gov (United States)

    Yamada, Yuzo; Toritsuka, Yukiyoshi; Nakamura, Norimasa; Horibe, Shuji; Sugamoto, Kazuomi; Yoshikawa, Hideki; Shino, Konsei

    2017-11-01

    The concepts of lateral deviation and lateral inclination of the patella, characterized as shift and tilt, have been applied in combination to evaluate patellar malalignment in patients with patellar dislocation. It is not reasonable, however, to describe the 3-dimensional (3D) positional relation between the patella and the femur according to measurements made on 2-dimensional (2D) images. The current study sought to clarify the relation between lateral deviation and inclination of the patella in patients with recurrent dislocation of the patella (RDP) by redefining them via 3D computer models as 3D shift and 3D tilt. Descriptive laboratory study. Altogether, 60 knees from 56 patients with RDP and 15 knees from 10 healthy volunteers were evaluated. 3D shift and tilt of the patella were analyzed with 3D computer models created by magnetic resonance imaging scans obtained at 10° intervals of knee flexion (0°-50°). 3D shift was defined as the spatial distance between the patellar reference point and the midsagittal plane of the femur; it is expressed as a percentage of the interepicondylar width. 3D tilt was defined as the spatial angle between the patellar reference plane and the transepicondylar axis. Correlations between the 2 parameters were assessed with the Pearson correlation coefficient. The patients' mean Pearson correlation coefficient was 0.895 ± 0.186 (range, -0.073 to 0.997; median, 0.965). In all, 56 knees (93%) had coefficients >0.7 (strong correlation); 1 knee (2%), >0.4 (moderate correlation); 2 knees (3%), >0.2 (weak correlation); and 1 knee (2%), correlation). The mean correlation coefficient of the healthy volunteers was 0.645 ± 0.448 (range, -0.445 to 0.982; median, 0.834). A statistically significant difference was found in the distribution of the correlation coefficients between the patients and the healthy volunteers ( P = .0034). When distribution of the correlation coefficients obtained by the 3D analyses was compared with that by the 2

  12. Prevalence and correlates of problematic internet experiences and computer-using time: a two-year longitudinal study in korean school children.

    Science.gov (United States)

    Yang, Su-Jin; Stewart, Robert; Lee, Ju-Yeon; Kim, Jae-Min; Kim, Sung-Wan; Shin, Il-Seon; Yoon, Jin-Sang

    2014-01-01

    To measure the prevalence of and factors associated with online inappropriate sexual exposure, cyber-bullying victimisation, and computer-using time in early adolescence. A two-year, prospective school survey was performed with 1,173 children aged 13 at baseline. Data collected included demographic factors, bullying experience, depression, anxiety, coping strategies, self-esteem, psychopathology, attention-deficit hyperactivity disorder symptoms, and school performance. These factors were investigated in relation to problematic Internet experiences and computer-using time at age 15. The prevalence of online inappropriate sexual exposure, cyber-bullying victimisation, academic-purpose computer overuse, and game-purpose computer overuse was 31.6%, 19.2%, 8.5%, and 21.8%, respectively, at age 15. Having older siblings, more weekly pocket money, depressive symptoms, anxiety symptoms, and passive coping strategy were associated with reported online sexual harassment. Male gender, depressive symptoms, and anxiety symptoms were associated with reported cyber-bullying victimisation. Female gender was associated with academic-purpose computer overuse, while male gender, lower academic level, increased height, and having older siblings were associated with game-purpose computer-overuse. Different environmental and psychological factors predicted different aspects of problematic Internet experiences and computer-using time. This knowledge is important for framing public health interventions to educate adolescents about, and prevent, internet-derived problems.

  13. Local Nucleosome Dynamics Facilitate Chromatin Accessibility in Living Mammalian Cells

    Directory of Open Access Journals (Sweden)

    Saera Hihara

    2012-12-01

    Full Text Available Genome information, which is three-dimensionally organized within cells as chromatin, is searched and read by various proteins for diverse cell functions. Although how the protein factors find their targets remains unclear, the dynamic and flexible nature of chromatin is likely crucial. Using a combined approach of fluorescence correlation spectroscopy, single-nucleosome imaging, and Monte Carlo computer simulations, we demonstrate local chromatin dynamics in living mammalian cells. We show that similar to interphase chromatin, dense mitotic chromosomes also have considerable chromatin accessibility. For both interphase and mitotic chromatin, we observed local fluctuation of individual nucleosomes (∼50 nm movement/30 ms, which is caused by confined Brownian motion. Inhibition of these