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Sample records for cerebral integrity track

  1. Can Structural MRI Indices of Cerebral Integrity Track Cognitive Trends in Executive Control Function During Normal Maturation and Adulthood?

    PubMed Central

    Kochunov, Peter; Robin, Don A.; Royall, Don R.; Coyle, Thomas; Lancaster, Jack; Kochunov, Valeria; Schlosser, Anita E.; Fox, Peter T.

    2009-01-01

    We explored the relationship between structural neuroimaging-based indices of cerebral integrity and executive control function (ECF) in two groups of healthy subjects: A maturing group (33 subjects; 19–29 years) and a senescing group (38 adults; 30–90 years). ECF was assessed using the Executive Interview (EXIT) battery. Cortical indices of cerebral integrity included GM thickness, intergyral span, and sulcal span, each measured for five cortical regions per hemisphere. Subcortical indices included fractional anisotropy (FA), measured using track-based-spatial-statistics (TBSS), and the volume of T2-hyperintense WM (HWM). In the maturing group, no significant relationships between neuroanatomical changes and ECF were found; however, there were hints that late-term maturation of cerebral WM influenced variability in ECF. In the senescing group, the decline in ECF corresponded to atrophic changes in cerebral WM (sulcal and intergyral span) primarily in the superior frontal and anterior cingulate regions. A large fraction of the variability in ECF (62%) can be explained by variability in the structural indices from these two regions. PMID:19067326

  2. Analyses of Disruption of Cerebral White Matter Integrity in Schizophrenia with MR Diffusion Tensor Fiber Tracking Method

    NASA Astrophysics Data System (ADS)

    Yamamoto, Utako; Kobayashi, Tetsuo; Kito, Shinsuke; Koga, Yoshihiko

    We have analyzed cerebral white matter using magnetic resonance diffusion tensor imaging (MR-DTI) to measure the diffusion anisotropy of water molecules. The goal of this study is the quantitative evaluation of schizophrenia. Diffusion tensor images are acquired for patients with schizophrenia and healthy comparison subjects, group-matched for age, sex, and handedness. Fiber tracking is performed on the superior longitudinal fasciculus for the comparison between the patient and comparison groups. We have analysed and compared the cross-sectional area on the starting coronal plane and the mean and standard deviation of the fractional anisotropy and the apparent diffusion coefficient along fibers in the right and left hemispheres. In the right hemisphere, the cross-sectional areas in patient group are significantly smaller than those in the comparison group. Furthermore, in the comparison group, the cross-sectional areas in the right hemisphere are significantly larger than those in the left hemisphere, whereas there is no significant difference in the patient group. These results suggest that we may evaluate the disruption in white matter integrity in schizophrenic patients quantitatively by comparing the cross-sectional area of the superior longitudinal fasciculus in the right and left hemispheres.

  3. Integrated Management Tracking System

    Energy Science and Technology Software Center (ESTSC)

    2000-03-30

    The Integrated Management Tracking System (IMTS) is a "Web Enabled" Client/Server Business application that provides for the Identification and Resolution of commitments, situations, events and problems. The IMTS engine is written with Microsoft Active Server Pages (ASP) for IIS4. The system provides for reporting, entering, editing, closing and administration over a Intranet, Extranet or Internet. This Application facilitates: Electronic assignment, acceptance and tracking to completion. Email notifications of assigned action. Establishment of Due Dates. Electronicmore » search and retrieval based on keywords in combination with user specified database parameters (Document Type, Date Ranges, etc.). Coded for Trending and Reporting. User selected reports. Various levels of access for reports and administration. The "Server" side of this application consists of a Microsoft Access database running on a NT Server with Internet Information Server (IIS). As the "Client" side of the application runs on any Web browser, this solution is a cost effective, user friendly application that lends itself to organizations not physically colocated in one location providing information immediately available to everyone at once.« less

  4. Integrated Management Tracking System

    SciTech Connect

    Garrett, Terrance

    2000-03-30

    The Integrated Management Tracking System (IMTS) is a "Web Enabled" Client/Server Business application that provides for the Identification and Resolution of commitments, situations, events and problems. The IMTS engine is written with Microsoft Active Server Pages (ASP) for IIS4. The system provides for reporting, entering, editing, closing and administration over a Intranet, Extranet or Internet. This Application facilitates: Electronic assignment, acceptance and tracking to completion. Email notifications of assigned action. Establishment of Due Dates. Electronic search and retrieval based on keywords in combination with user specified database parameters (Document Type, Date Ranges, etc.). Coded for Trending and Reporting. User selected reports. Various levels of access for reports and administration. The "Server" side of this application consists of a Microsoft Access database running on a NT Server with Internet Information Server (IIS). As the "Client" side of the application runs on any Web browser, this solution is a cost effective, user friendly application that lends itself to organizations not physically colocated in one location providing information immediately available to everyone at once.

  5. Integrated eyeball-tracking device

    NASA Astrophysics Data System (ADS)

    Chen, Hunglin; Yen, Kaihsiang; Chio, Jinhung; Huang, Huiwen; Dai, Chingliang; Chang, Chienliu; Chang, Peizen

    2000-07-01

    This investigation presents a concept of integrated device, which tracks the movement of eyeball in real time. Integrated optical components are applied to perform infrared oculography to find the position of the eyeball. First, the photodiodes emits infrared to human eyes via the output coupler, then the reflected light is collected by the input coupler and detected by the photodetectors. By analyzing the electrical signal, we could figure the position of the eyeball out. The basic principle is based on the differential of reflected index between sclera and iris. The light source and detectors are settled on the side of goggles worn and, in doing so, the eyesight could be wide without obstacles. Therefore, the optical guiding interconnection is an essential issue for the eyeball- tracking device. Since the fine line gratings are necessary for the optical coupler, the electron beam writing is used to meet the requirement. The gratings with 40 nm line width are achieved, and it is sufficient for optical coupling. On the other hand, the electrical signal related eyeball position is simulated. We could translate the electrical signal readout into the coordinate of the eyeball position. The whole eyeball-tracking device would be small volume, less weight, and portable.

  6. Transverse Diffusivity of Cerebral Parenchyma Predicts Visual Tracking Performance in Relapsing-Remitting Multiple Sclerosis

    ERIC Educational Resources Information Center

    Warlop, Nele P.; Achten, Eric; Fieremans, Els; Debruyne, Jan; Vingerhoets, Guy

    2009-01-01

    This study investigated the relation between cerebral damage related to multiple sclerosis (MS) and cognitive decline as determined by two classical mental tracking tests. Cerebral damage in 15 relapsing-remitting MS patients was measured by diffusion tensor imaging (DTI). Fractional anisotropy, longitudinal and transverse diffusivity were defined…

  7. Intelligent Human Tracking Based on Multimodal Integration

    NASA Astrophysics Data System (ADS)

    Nakamura, Keisuke; Nakadai, Kazuhiro; Asano, Futoshi; Nakajima, Hirofumi; Ince, Gökhan

    Localization and tracking of humans are essential research topics in robotics. In particular, Sound Source Localization (SSL) has been of great interest. Despite the numerous reported methods, SSL in a real environment had mainly three issues; robustness against noise with high power, no framework for selective listening to sound sources, and tracking of inactive and/or noisy sound sources. For the first issue, we extended Multiple SIgnal Classification by incorporating Generalized Eigen Value Decomposition (GEVD-MUSIC) so that it can deal with high power noise and can select target sound sources. For the second issue, we proposed Sound Source Identification (SSI) based on hierarchical Gaussian mixture models and integrated it with GEVD-MUSIC to realize a function to listen to a specific sound source according to the sort of the sound source. For the third issue, auditory and visual human tracking were integrated using particle filtering. These three techniques are integrated into an intelligent human tracking system. Experimental results showed that integration of SSL and SSI successfully achieved human tracking only by audition, and the audio-visual integration showed considerable improvement in tracking by compensating the loss of auditory or visual information.

  8. Dynamic kirigami structures for integrated solar tracking

    PubMed Central

    Lamoureux, Aaron; Lee, Kyusang; Shlian, Matthew; Forrest, Stephen R.; Shtein, Max

    2015-01-01

    Optical tracking is often combined with conventional flat panel solar cells to maximize electrical power generation over the course of a day. However, conventional trackers are complex and often require costly and cumbersome structural components to support system weight. Here we use kirigami (the art of paper cutting) to realize novel solar cells where tracking is integral to the structure at the substrate level. Specifically, an elegant cut pattern is made in thin-film gallium arsenide solar cells, which are then stretched to produce an array of tilted surface elements which can be controlled to within ±1°. We analyze the combined optical and mechanical properties of the tracking system, and demonstrate a mechanically robust system with optical tracking efficiencies matching conventional trackers. This design suggests a pathway towards enabling new applications for solar tracking, as well as inspiring a broader range of optoelectronic and mechanical devices. PMID:26348820

  9. Dynamic kirigami structures for integrated solar tracking

    NASA Astrophysics Data System (ADS)

    Lamoureux, Aaron; Lee, Kyusang; Shlian, Matthew; Forrest, Stephen R.; Shtein, Max

    2015-09-01

    Optical tracking is often combined with conventional flat panel solar cells to maximize electrical power generation over the course of a day. However, conventional trackers are complex and often require costly and cumbersome structural components to support system weight. Here we use kirigami (the art of paper cutting) to realize novel solar cells where tracking is integral to the structure at the substrate level. Specifically, an elegant cut pattern is made in thin-film gallium arsenide solar cells, which are then stretched to produce an array of tilted surface elements which can be controlled to within +/-1°. We analyze the combined optical and mechanical properties of the tracking system, and demonstrate a mechanically robust system with optical tracking efficiencies matching conventional trackers. This design suggests a pathway towards enabling new applications for solar tracking, as well as inspiring a broader range of optoelectronic and mechanical devices.

  10. Dynamic kirigami structures for integrated solar tracking.

    PubMed

    Lamoureux, Aaron; Lee, Kyusang; Shlian, Matthew; Forrest, Stephen R; Shtein, Max

    2015-01-01

    Optical tracking is often combined with conventional flat panel solar cells to maximize electrical power generation over the course of a day. However, conventional trackers are complex and often require costly and cumbersome structural components to support system weight. Here we use kirigami (the art of paper cutting) to realize novel solar cells where tracking is integral to the structure at the substrate level. Specifically, an elegant cut pattern is made in thin-film gallium arsenide solar cells, which are then stretched to produce an array of tilted surface elements which can be controlled to within ±1°. We analyze the combined optical and mechanical properties of the tracking system, and demonstrate a mechanically robust system with optical tracking efficiencies matching conventional trackers. This design suggests a pathway towards enabling new applications for solar tracking, as well as inspiring a broader range of optoelectronic and mechanical devices. PMID:26348820

  11. Tracking-integrated systems for concentrating photovoltaics

    NASA Astrophysics Data System (ADS)

    Apostoleris, Harry; Stefancich, Marco; Chiesa, Matteo

    2016-04-01

    Concentrating photovoltaic (CPV) systems, which use optical elements to focus light onto small-area solar cells, have the potential to minimize the costs, while improving efficiency, of photovoltaic technology. However, CPV is limited by the need to track the apparent motion of the Sun. This is typically accomplished using high-precision mechanical trackers that rotate the entire module to maintain normal light incidence. These machines are large, heavy and expensive to build and maintain, deterring commercial interest and excluding CPV from the residential market. To avoid this issue, some attention has recently been devoted to the development of tracking-integrated systems, in which tracking is performed inside the CPV module itself. This creates a compact system geometry that could be less expensive and more suitable for rooftop installation than existing CPV trackers. We review the basic tracking principles and concepts exploited in these systems, describe and categorize the existing designs, and discuss the potential impact of tracking integration on CPV cost models and commercial potential.

  12. Field weighting model for tracking-integrated optics

    NASA Astrophysics Data System (ADS)

    Wheelwright, Brian; Angel, Roger; Coughenour, Blake; Hammer, Kimberly; Geary, Andrew; Stalcup, Thomas

    2014-09-01

    The emergent field of tracking-integrated optics enables a potentially low cost concentrating photovoltaic (CPV) implementation, where single-axis module tracking is complemented by an additional degree of freedom within the module [1,2,3,4,5]. Gross module tracking can take on multiple configurations, the most common being rotation about a polar or horizontal North-South oriented axis. Polar-axis tracking achieves >95% sunlight collection compared to dual-axis tracking[6], leaving the tracking-integrated optics to compensate for +/-23.5° seasonal variations. The collection efficiency of N-S horizontal axis tracking is latitude-dependent, with ˜90% collection relative to dual-axis tracking at 32.2° latitude. Horizontal tracking at higher latitudes shifts an increasing burden to the tracking-integrated optics, which must operate between two incidence angle extremes: summer solstice sunrise/sunset to winter solstice noon. An important aspect of tracking-integrated lens design is choosing a suitable field weighting to appropriately account for annual DNI received at each angle of incidence. We present a field weighting model, generalized for polar or horizontal module tracking at any latitude, which shows excellent agreement with measured insolation data. This model is particularly helpful for the design of tracking-integrated optics for horizontally-tracked modules, where the correct field weighting is asymmetric and significantly biased away from the normal incidence.

  13. Tracking-integrated optics: applications in solar concentration

    NASA Astrophysics Data System (ADS)

    Wheelwright, Brian M.; Angel, Roger; Coughenour, Blake

    2014-12-01

    Conventional concentrating photovoltaic (CPV) systems track the sun with high precision dual-axis trackers. The emergent field of tracking-integrated optics has the potential to simplify the mechanics of CPV systems by loosening or eliminating the need for dual-axis tracking. In a tracking-integrated scheme, external module tracking is complemented or entirely replaced by miniature tracking within the module. This internal tracking-integration may take the form of active small-motion translation, rotation of arrayed optics, or by passive material property changes induced by the concentrated light. These methods are briefly reviewed. An insolation weighting model is presented which will aid in the design of tracking-integrated optics by quantifying the tradeoff between angular operation range and annual sunlight collection. We demonstrate that when tracking-integrated optics are used to complement external module tracking about a horizontal, North-South oriented axis, truncating the operational range may be advantageous. At Tucson AZ latitude (32.2°N), 15.6% of the angular range may be truncated while only sacrificing 3.6% of the annual insolation. We show that modules tracked about a polar-aligned axis are poorly-suited for truncation.

  14. Integral -tracking extreme radiation across the Universe

    NASA Astrophysics Data System (ADS)

    2002-10-01

    the four instruments is about 2 tonnes, roughly half the launch weight of Integral. Integral's orbit and operations After launch, Integral will follow an elliptical orbit that is inclined by 51.6° to the Earth’s equator. In this orbit, it will cycle between 9000 kilometres and 153 000 kilometres above Earth, completing one revolution of the Earth every 72 hours. This eccentric orbit is necessary because there are ‘radiation belts’ that surround the Earth and these would interfere with Integral’s ability to see gamma rays. It is important for Integral to be outside these belts. Its elliptical orbit is designed to keep it outside the radiation belts for 90% of its trajectory around Earth. Once Integral is in orbit, it must communicate with Earth to download its scientific data and to receive commands. Communicating with and controlling Integral is a task spread over a number of different sites. Firstly, astronomers submit proposals for observations to the Integral Science Operations Centre (ISOC) at Noordwijk, The Netherlands. Experts at ISOC evaluate the proposals and draw up a list of targets and detailed observation schedules for Integral. The schedules are sent to the Mission Operations Centre (MOC) at the European Space Operations Centre (ESOC) in Darmstadt, Germany. There everything is transformed into commands that Integral will understand. Signals to and from Integral go through two tracking stations, one at Redu in Belgium, the second at Goldstone in California, United States. The MOC also ensures the correct performance of the spacecraft. After Integral has collected observations, the raw science data is forwarded to the Integral Science Data Centre (ISDC) in Versoix near Geneva, Switzerland. There it is converted into usable data files, archived, and distributed to the astronomical community. A worldwide network of space science institutes and observatories will receive the data very quickly. This is essential especially when sudden and short

  15. Proton spin tracking with symplectic integration of orbit motion

    SciTech Connect

    Luo, Y.; Dutheil, Y.; Huang, H.; Meot, F.; Ranjbar, V.

    2015-05-03

    Symplectic integration had been adopted for orbital motion tracking in code SimTrack. SimTrack has been extensively used for dynamic aperture calculation with beam-beam interaction for the Relativistic Heavy Ion Collider (RHIC). Recently proton spin tracking has been implemented on top of symplectic orbital motion in this code. In this article, we will explain the implementation of spin motion based on Thomas-BMT equation, and the benchmarking with other spin tracking codes currently used for RHIC. Examples to calculate spin closed orbit and spin tunes are presented too.

  16. Spread Of Charge From Ion Tracks In Integrated Circuits

    NASA Technical Reports Server (NTRS)

    Zoutendyk, John A.; Schwartz, Harvey R.; Watson, R. Kevin; Nevill, Leland R.

    1989-01-01

    Single-event upsets (SEU's) propagate to adjacent cells in integrated memory circuits. Findings of experiments in lateral transport of electrical-charge carriers from ion tracks in 256K dynamic randon-access memories (DRAM's). As dimensions of integrated circuits decrease, vulnerability to SEU's increases. Understanding gained enables design of less vulnerable circuits.

  17. Integration of Nanotubes, Etch Tracks, and Nanoribbons in Crystallographic Alignment

    NASA Astrophysics Data System (ADS)

    Boland, Mathias J.; Hunley, D. Patrick; Sundrarajan, Abhishek; Nasseri, Mohsen; Strachan, Douglas R.

    2015-03-01

    Three nanomaterial components, carbon nanotubes (CNTs), few-layer graphene (FLG), and etch tracks exposing insulating SiO2 regions, are integrated to form crystallographically-aligned nanoscale systems. These integrated systems consist of CNTs grown across nanogap etch tracks and nanoribbons formed within the FLG films as a result of chemical vapor deposition (CVD) processing. Each nanoscale component is aligned along the underlying graphene lattice, resulting in their orientations being locked into precise values, with CNTs maintaining alignment even after crossing etch tracks. The growth of aligned CNTs across nanogap etch tracks and nanoribbons suggests that integrated formations can be achieved by growing CNTs directly over nanogap etch tracks and nanoribbons. This is supported by calculations of the vibrational energy of CNTs indicating that they should be capable of maintaining atomic registry with an underlying graphene lattice as they grow across a typical etch track, in agreement with our experimental results. Thus, this work is relevant to the integration of semiconducting, conducting, and insulating nano-materials all together into precise nano-electronic systems.

  18. Learning a Tracking and Estimation Integrated Graphical Model for Human Pose Tracking.

    PubMed

    Zhao, Lin; Gao, Xinbo; Tao, Dacheng; Li, Xuelong

    2015-12-01

    We investigate the tracking of 2-D human poses in a video stream to determine the spatial configuration of body parts in each frame, but this is not a trivial task because people may wear different kinds of clothing and may move very quickly and unpredictably. The technology of pose estimation is typically applied, but it ignores the temporal context and cannot provide smooth, reliable tracking results. Therefore, we develop a tracking and estimation integrated model (TEIM) to fully exploit temporal information by integrating pose estimation with visual tracking. However, joint parsing of multiple articulated parts over time is difficult, because a full model with edges capturing all pairwise relationships within and between frames is loopy and intractable. In previous models, approximate inference was usually resorted to, but it cannot promise good results and the computational cost is large. We overcome these problems by exploring the idea of divide and conquer, which decomposes the full model into two much simpler tractable submodels. In addition, a novel two-step iteration strategy is proposed to efficiently conquer the joint parsing problem. Algorithmically, we design TEIM very carefully so that: 1) it enables pose estimation and visual tracking to compensate for each other to achieve desirable tracking results; 2) it is able to deal with the problem of tracking loss; and 3) it only needs past information and is capable of tracking online. Experiments are conducted on two public data sets in the wild with ground truth layout annotations, and the experimental results indicate the effectiveness of the proposed TEIM framework. PMID:25826809

  19. Downsizing of an integrated tracking unit for multiple applications

    NASA Astrophysics Data System (ADS)

    Steinway, William J.; Thomas, James E.; Nicoloff, Michael J.; Patz, Mark D.

    1997-02-01

    This paper describes the specifications and capabilities of the integrated tracking unit (ITU) and its multiple applications are presented. The original ITU was developed by Coleman Research Corporation (CRC) for several federal law enforcement agencies over a four-year period and it has been used for friendly and unfriendly vehicle and person position tracking. The ITU has been down-sized to reduce its physical size, weight, and power requirements with respect to the first generation unit. The ITU consists of a global positioning system (GPS) receiver for precise position location and a cellular phone to transmit voice and data to a PC base station with a modem interface. This paper describes the down-sizing of the unit introduced in CRC's 'An Integrated Tracking Unit for Multiple Applications' paper presented at the 1995 Counterdrug Technology Assessment Center's symposium in Nashua, NH. This paper provides a description of the ITU and tested applications.

  20. Wireless handheld scanners integrated with waste tracking

    SciTech Connect

    R. S. Anderson

    2000-07-23

    The US Department of Energy (DOE) Idaho National Engineering and Environmental Laboratory (INEEL) has embraced mobile wireless technology to help the disposition of hazardous and mixed radiological waste. The following paper describes one application the INEEL developed to increase the data accuracy and near-real time reporting requirements for waste management. With the continuous operational demands at the ''site'', it was difficult to sustain an accurate, up-to-date database required for regulatory compliance audits and reporting. Incorporating wireless mobile technology, the INEEL was able to increase the accuracy while reducing the data delay times previously encountered. Installation issues prolonged the project along with obstacles encountered with operations personnel. However, the success of this project was found in persistence and management support as well as the technology itself. Future wireless, mobile computing will continue at the INEEL for years to come based on a successful project that was able to integrate new technology to an existing waste management system with proven, increased data accuracy.

  1. Wireless Handheld Scanners Integrated with Waste Tracking

    SciTech Connect

    Anderson, Robert Stephen

    2000-07-01

    The US Department of Energy (DOE) Idaho National Engineering and Environmental Laboratory (INEEL) has embraced mobile wireless technology to help the disposition of hazardous and mixed radiological waste. The following paper describes one application the INEEL developed to increase the data accuracy and near-real time reporting requirements for waste management. With the continuous operational demands at the "site", it was difficult to sustain an accurate, up-to-date database required for regulatory compliance audits and reporting. Incorporating wireless mobile technology, the INEEL was able to increase the accuracy while reducing the data delay times previously encountered. Installation issues prolonged the project along with obstacles encountered with operations personnel. However, the success of this project was found in persistence and management support as well as the technology itself. Future wireless, mobile computing will continue at the INEEL for years to come based on a successful project that was able to integrate new technology to an existing waste management system with proven, increased data accuracy.

  2. Accurate object tracking system by integrating texture and depth cues

    NASA Astrophysics Data System (ADS)

    Chen, Ju-Chin; Lin, Yu-Hang

    2016-03-01

    A robust object tracking system that is invariant to object appearance variations and background clutter is proposed. Multiple instance learning with a boosting algorithm is applied to select discriminant texture information between the object and background data. Additionally, depth information, which is important to distinguish the object from a complicated background, is integrated. We propose two depth-based models that can compensate texture information to cope with both appearance variants and background clutter. Moreover, in order to reduce the risk of drifting problem increased for the textureless depth templates, an update mechanism is proposed to select more precise tracking results to avoid incorrect model updates. In the experiments, the robustness of the proposed system is evaluated and quantitative results are provided for performance analysis. Experimental results show that the proposed system can provide the best success rate and has more accurate tracking results than other well-known algorithms.

  3. The Integrated Waste Tracking System - A Flexible Waste Management Tool

    SciTech Connect

    Anderson, Robert Stephen

    2001-02-01

    The US Department of Energy (DOE) Idaho National Engineering and Environmental Laboratory (INEEL) has fully embraced a flexible, computer-based tool to help increase waste management efficiency and integrate multiple operational functions from waste generation through waste disposition while reducing cost. The Integrated Waste Tracking System (IWTS)provides comprehensive information management for containerized waste during generation,storage, treatment, transport, and disposal. The IWTS provides all information necessary for facilities to properly manage and demonstrate regulatory compliance. As a platformindependent, client-server and Web-based inventory and compliance system, the IWTS has proven to be a successful tracking, characterization, compliance, and reporting tool that meets the needs of both operations and management while providing a high level of management flexibility.

  4. Integrated tracking of components by engineering and logistics utilizing logistics asset tracking system

    NASA Technical Reports Server (NTRS)

    Renfroe, Michael B.; Mcdonald, Edward J.; Bradshaw, Kimberly

    1988-01-01

    The Logistics Asset Tracking System (LATS) devised by NASA contains data on Space Shuttle LRUs that are daily updated to reflect such LRU status changes as repair due to failure or modification due to changing engineering requirements. The implementation of LATS has substantially increased personnel responsiveness, preventing costly delays in Space Shuttle processing and obviating hardware cannibalization. An evaluation is presented of LATS achievements in the direction of an integrated logistical support posture.

  5. Cerebral White Matter Integrity Mediates Adult Age Differences in Cognitive Performance

    ERIC Educational Resources Information Center

    Madden, David J.; Spaniol, Julia; Costello, Matthew C.; Bucur, Barbara; White, Leonard E.; Cabeza, Roberto; Davis, Simon W.; Dennis, Nancy A.; Provenzale, James M.; Huettel, Scott A.

    2009-01-01

    Previous research has established that age-related decline occurs in measures of cerebral white matter integrity, but the role of this decline in age-related cognitive changes is not clear. To conclude that white matter integrity has a mediating (causal) contribution, it is necessary to demonstrate that statistical control of the white…

  6. Integrative physiologic and computational approaches to understand autonomic control of cerebral autoregulation

    PubMed Central

    Tan, Can Ozan; Taylor, J. Andrew

    2013-01-01

    The brain requires steady delivery of oxygen and glucose, without which neurodegeneration occurs within minutes. Thus, the ability of the cerebral vasculature to maintain relatively steady blood flow in the face of changing systemic pressure, i.e., cerebral autoregulation, is critical to neurophysiologic health. Although the study of autoregulation dates to the early 20th century, only the recent availability of cerebral blood flow measures with high temporal resolution has allowed rapid, beat-by-beat measurements to explore the characteristics and mechanisms of autoregulation. These explorations have been further enhanced by the ability to apply sophisticated computational approaches that exploit the large amounts of data that can be acquired. These advances have led to unique insights. For example, recent studies have revealed characteristic time scales wherein cerebral autoregulation is most active, and specific regions wherein autonomic mechanisms are prepotent. However, given that effective cerebral autoregulation against pressure fluctuations results in relatively unchanging flow despite changing pressure, estimating the pressure-flow relationship can be limited by the error inherent in computational models of autoregulatory function. This review will focus on the autonomic neural control of the cerebral vasculature in health and disease from an integrative physiologic and perspective. It will also provide a critical overview of the current analytic approaches to understand cerebral autoregulation. PMID:24097158

  7. EEG and Eye Tracking Demonstrate Vigilance Enhancement with Challenge Integration

    PubMed Central

    Bodala, Indu P.; Li, Junhua; Thakor, Nitish V.; Al-Nashash, Hasan

    2016-01-01

    Maintaining vigilance is possibly the first requirement for surveillance tasks where personnel are faced with monotonous yet intensive monitoring tasks. Decrement in vigilance in such situations could result in dangerous consequences such as accidents, loss of life and system failure. In this paper, we investigate the possibility to enhance vigilance or sustained attention using “challenge integration,” a strategy that integrates a primary task with challenging stimuli. A primary surveillance task (identifying an intruder in a simulated factory environment) and a challenge stimulus (periods of rain obscuring the surveillance scene) were employed to test the changes in vigilance levels. The effect of integrating challenging events (resulting from artificially simulated rain) into the task were compared to the initial monotonous phase. EEG and eye tracking data is collected and analyzed for n = 12 subjects. Frontal midline theta power and frontal theta to parietal alpha power ratio which are used as measures of engagement and attention allocation show an increase due to challenge integration (p < 0.05 in each case). Relative delta band power of EEG also shows statistically significant suppression on the frontoparietal and occipital cortices due to challenge integration (p < 0.05). Saccade amplitude, saccade velocity and blink rate obtained from eye tracking data exhibit statistically significant changes during the challenge phase of the experiment (p < 0.05 in each case). From the correlation analysis between the statistically significant measures of eye tracking and EEG, we infer that saccade amplitude and saccade velocity decrease with vigilance decrement along with frontal midline theta and frontal theta to parietal alpha ratio. Conversely, blink rate and relative delta power increase with vigilance decrement. However, these measures exhibit a reverse trend when challenge stimulus appears in the task suggesting vigilance enhancement. Moreover, the mean

  8. EEG and Eye Tracking Demonstrate Vigilance Enhancement with Challenge Integration.

    PubMed

    Bodala, Indu P; Li, Junhua; Thakor, Nitish V; Al-Nashash, Hasan

    2016-01-01

    Maintaining vigilance is possibly the first requirement for surveillance tasks where personnel are faced with monotonous yet intensive monitoring tasks. Decrement in vigilance in such situations could result in dangerous consequences such as accidents, loss of life and system failure. In this paper, we investigate the possibility to enhance vigilance or sustained attention using "challenge integration," a strategy that integrates a primary task with challenging stimuli. A primary surveillance task (identifying an intruder in a simulated factory environment) and a challenge stimulus (periods of rain obscuring the surveillance scene) were employed to test the changes in vigilance levels. The effect of integrating challenging events (resulting from artificially simulated rain) into the task were compared to the initial monotonous phase. EEG and eye tracking data is collected and analyzed for n = 12 subjects. Frontal midline theta power and frontal theta to parietal alpha power ratio which are used as measures of engagement and attention allocation show an increase due to challenge integration (p < 0.05 in each case). Relative delta band power of EEG also shows statistically significant suppression on the frontoparietal and occipital cortices due to challenge integration (p < 0.05). Saccade amplitude, saccade velocity and blink rate obtained from eye tracking data exhibit statistically significant changes during the challenge phase of the experiment (p < 0.05 in each case). From the correlation analysis between the statistically significant measures of eye tracking and EEG, we infer that saccade amplitude and saccade velocity decrease with vigilance decrement along with frontal midline theta and frontal theta to parietal alpha ratio. Conversely, blink rate and relative delta power increase with vigilance decrement. However, these measures exhibit a reverse trend when challenge stimulus appears in the task suggesting vigilance enhancement. Moreover, the mean reaction

  9. Switching modes in corticogenesis: mechanisms of neuronal subtype transitions and integration in the cerebral cortex

    PubMed Central

    Toma, Kenichi; Hanashima, Carina

    2015-01-01

    Information processing in the cerebral cortex requires the activation of diverse neurons across layers and columns, which are established through the coordinated production of distinct neuronal subtypes and their placement along the three-dimensional axis. Over recent years, our knowledge of the regulatory mechanisms of the specification and integration of neuronal subtypes in the cerebral cortex has progressed rapidly. In this review, we address how the unique cytoarchitecture of the neocortex is established from a limited number of progenitors featuring neuronal identity transitions during development. We further illuminate the molecular mechanisms of the subtype-specific integration of these neurons into the cerebral cortex along the radial and tangential axis, and we discuss these key features to exemplify how neocortical circuit formation accomplishes economical connectivity while maintaining plasticity and evolvability to adapt to environmental changes. PMID:26321900

  10. A passive integrated transponder system for tracking animal movements

    USGS Publications Warehouse

    Boarman, W.I.; Beigel, M.L.; Goodlett, G.C.; Sazaki, M.

    1999-01-01

    We describe an automated system that uses passive integrated transponder (PIT) tags to track movements of animals past specific locations. The system was designed to operate maintenance free for several months, be secure from vandalism and environmental damage, and record the identity, date, and time of passage of animals past a 2.4-m wide area. We used the system to monitor effectively the movements of 172 desert tortoises (Gopherus agassizii) through 2 storm drain culverts that pass beneath a state highway in the Mojave Desert, California. Four tortoises entered or passed through the culverts on 60 occasions. The system can be easily adapted to other species.

  11. Integrated laser/radar satellite ranging and tracking system

    NASA Technical Reports Server (NTRS)

    Hoge, F. E.

    1974-01-01

    A laser satellite ranging system that is mounted upon and integrated with a microwave tracking radar is reported. The 1-pulse/sec ruby laser transmitter is attached directly to the radar's elevation axis and radiates through a new opening in the radar's parabolic dish. The laser photomultiplier tube receiver utilizes the radar's existing 20-cm diam f/11 boresight telescope and observes through a similar symmetrically located opening in the dish. The laser system possesses separate ranging system electronics but shares the radar's timing, computer, and data handling/recording systems. The basic concept of the laser/radar is outlined together with a listing of the numerous advantages over present singular laser range-finding systems. The developmental laser hardware is described along with preliminary range-finding results and expectations.

  12. IMPACT: Integrated Modeling of Perturbations in Atmospheres for Conjunction Tracking

    NASA Astrophysics Data System (ADS)

    Koller, J.; Brennan, S.; Godinez, H. C.; Higdon, D. M.; Klimenko, A.; Larsen, B.; Lawrence, E.; Linares, R.; McLaughlin, C. A.; Mehta, P. M.; Palmer, D.; Ridley, A. J.; Shoemaker, M.; Sutton, E.; Thompson, D.; Walker, A.; Wohlberg, B.

    2013-12-01

    Low-Earth orbiting satellites suffer from atmospheric drag due to thermospheric density which changes on the order of several magnitudes especially during space weather events. Solar flares, precipitating particles and ionospheric currents cause the upper atmosphere to heat up, redistribute, and cool again. These processes are intrinsically included in empirical models, e.g. MSIS and Jacchia-Bowman type models. However, sensitivity analysis has shown that atmospheric drag has the highest influence on satellite conjunction analysis and empirical model still do not adequately represent a desired accuracy. Space debris and collision avoidance have become an increasingly operational reality. It is paramount to accurately predict satellite orbits and include drag effect driven by space weather. The IMPACT project (Integrated Modeling of Perturbations in Atmospheres for Conjunction Tracking), funded with over $5 Million by the Los Alamos Laboratory Directed Research and Development office, has the goal to develop an integrated system of atmospheric drag modeling, orbit propagation, and conjunction analysis with detailed uncertainty quantification to address the space debris and collision avoidance problem. Now with over two years into the project, we have developed an integrated solution combining physics-based density modeling of the upper atmosphere between 120-700 km altitude, satellite drag forecasting for quiet and disturbed geomagnetic conditions, and conjunction analysis with non-Gaussian uncertainty quantification. We are employing several novel approaches including a unique observational sensor developed at Los Alamos; machine learning with a support-vector machine approach of the coupling between solar drivers of the upper atmosphere and satellite drag; rigorous data assimilative modeling using a physics-based approach instead of empirical modeling of the thermosphere; and a computed-tomography method for extracting temporal maps of thermospheric densities

  13. Cerebral white matter integrity during primary HIV infection

    PubMed Central

    Wright, Patrick W.; Vaida, Florin F.; Fernández, Ricardo J.; Rutlin, Jerrel; Price, Richard W.; Lee, Evelyn; Peterson, Julia; Fuchs, Dietmar; Shimony, Joshua S.; Robertson, Kevin R.; Walter, Rudolph; Meyerhoff, Dieter J.; Spudich, Serena; Ances, Beau M.

    2016-01-01

    Objective Inflammation and infection within the central nervous system is initiated during primary HIV infection (PHI), but the association of these processes with the integrity of brain white matter during PHI is unknown. Design We used diffusion tensor imaging (DTI) in this prospective cross-sectional neuroimaging study to determine the extent of white matter involvement in early HIV infection. Methods Antiretroviral-naive PHI (defined as <1 year after infection, n = 62), chronic HIV infection (CHI, n = 16), and HIV-uninfected (n = 19) participants had DTI, laboratory, and neuropsychometric performance assessments. DTI metrics were examined using region of interest and whole brain voxelwise analyses. Linear mixed-effects models assessed correlations between DTI measures and laboratory and neuropsychometric performance values. Results PHI participants were assessed at a median 4.1 months after estimated infection, and had median CD4+ cell count of 573 cells/µl, and HIV-1 RNA viral load of 4.5 log10 copies/ml in plasma and 2.6 log10 copies/ml in cerebrospinal fluid (CSF). DTI metrics in PHI individuals were similar to HIV— participants and correlated with disruptions in the blood-brain barrier (indicated by CSF/plasma albumin ratio and CSF protein). CHI participants had significant loss of white matter integrity that correlated with biomarkers of infection and inflammation (blood viral load, CD4+ T-cell count, and neopterin, and CSF white blood cell). Within the PHI group, DTI metrics inversely correlated with increasing days since infection. Conclusion In individuals assessed during PHI, group DTI measures suggested relative preservation of white matter microstructural integrity, but were associated with disruption of the blood-brain barrier and estimated duration of infection. PMID:25513818

  14. Integrating optical finger motion tracking with surface touch events.

    PubMed

    MacRitchie, Jennifer; McPherson, Andrew P

    2015-01-01

    This paper presents a method of integrating two contrasting sensor systems for studying human interaction with a mechanical system, using piano performance as the case study. Piano technique requires both precise small-scale motion of fingers on the key surfaces and planned large-scale movement of the hands and arms. Where studies of performance often focus on one of these scales in isolation, this paper investigates the relationship between them. Two sensor systems were installed on an acoustic grand piano: a monocular high-speed camera tracking the position of painted markers on the hands, and capacitive touch sensors attach to the key surfaces which measure the location of finger-key contacts. This paper highlights a method of fusing the data from these systems, including temporal and spatial alignment, segmentation into notes and automatic fingering annotation. Three case studies demonstrate the utility of the multi-sensor data: analysis of finger flexion or extension based on touch and camera marker location, timing analysis of finger-key contact preceding and following key presses, and characterization of individual finger movements in the transitions between successive key presses. Piano performance is the focus of this paper, but the sensor method could equally apply to other fine motor control scenarios, with applications to human-computer interaction. PMID:26082732

  15. Integrating optical finger motion tracking with surface touch events

    PubMed Central

    MacRitchie, Jennifer; McPherson, Andrew P.

    2015-01-01

    This paper presents a method of integrating two contrasting sensor systems for studying human interaction with a mechanical system, using piano performance as the case study. Piano technique requires both precise small-scale motion of fingers on the key surfaces and planned large-scale movement of the hands and arms. Where studies of performance often focus on one of these scales in isolation, this paper investigates the relationship between them. Two sensor systems were installed on an acoustic grand piano: a monocular high-speed camera tracking the position of painted markers on the hands, and capacitive touch sensors attach to the key surfaces which measure the location of finger-key contacts. This paper highlights a method of fusing the data from these systems, including temporal and spatial alignment, segmentation into notes and automatic fingering annotation. Three case studies demonstrate the utility of the multi-sensor data: analysis of finger flexion or extension based on touch and camera marker location, timing analysis of finger-key contact preceding and following key presses, and characterization of individual finger movements in the transitions between successive key presses. Piano performance is the focus of this paper, but the sensor method could equally apply to other fine motor control scenarios, with applications to human-computer interaction. PMID:26082732

  16. IMPACT: Integrated Modeling of Perturbations in Atmospheres for Conjunction Tracking

    NASA Astrophysics Data System (ADS)

    Koller, J.; Ridley, A. J.; Godinez, H. C.; Impact Team

    2011-12-01

    Our society relies heavily on its space infrastructure for a vast number of applications. However, NASA predicts that between now and 2030 orbital collisions will become increasingly frequent and could reach a run-away environment - the so-called Kessler Syndrome. Preventing this scenario requires, in addition to an object removal technique, an improved new orbital dynamics framework with improved drag predictions based on thermospheric densities and wind velocities. In particular for LEO (Low Earth Orbit) objects, satellite drag due to atmospheric friction is the major non-conservative force that can lead to significant errors. To achieve the goal of improved orbital drag specification, the IMPACT project (Integrated Modeling of Perturbations in Atmospheres for Conjunction Tracking) will employ a comprehensive physics-based model of the thermosphere GITM. The GITM model (Global Ionosphere-Thermosphere Model), developed at the University of Michigan, is solving the full hydrodynamic equation without assuming hydrostatic equilibrium and also includes heating and cooling processes that are causing the density variations and thermospheric wind velocities in the upper atmosphere. The model is coupled to solar and magnetospheric drivers and is, therefore, ideally suited for orbital drag calculations that include relative wind velocities. We will present a study of thermospheric wind velocities as predicted with GITM and compared to observations. We will use the results for orbital drag calculations and determine the sensitivity of the errors in orbital predictions as a function of thermospheric density and wind velocities and how they can alter the orbit of LEO objects and lead to significant errors in orbital predictions. This work is a major new investment at Los Alamos National Laboratory funded by the Laboratory Directed Research and Development (LDRD) program and we gratefully acknowledge the support of the U.S. Department of Energy for this work.

  17. CPV for the rooftop market: novel approaches to tracking integration in photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Apostoleris, Harry; Stefancich, Marco; Alexander-Katz, Alfredo; Chiesa, Matteo

    2016-03-01

    Concentrated photovoltaics (CPV) has long been recognized as an effective approach to enabling the use of high cost, high-efficiency solar cells for enhanced solar energy conversion, but is excluded from the domestic rooftop market due to the requirement that solar concentrators track the sun. This market may be opened up by integrating of the tracking mechanism into the module itself. Tracking integration may take the form of a miniaturization of a conventional tracking apparatus, or optical tracking, in which tracking is achieved through variation of optical properties such as refractive index or transparency rather than mechanical movement of the receiver. We have demonstrated a simple system using a heat-responsive transparency switching material to create a moving aperture that tracks the position of a moving light spot. We use this behavior to create a concentrating light trap with a moving aperture that reactively tracks the sun. Taking the other approach, we have fabricated 3D-printed parabolic mini-concentrators which can track the sun using small motors in a low-profile geometry. We characterize the performance of the concentrators and consider the impact of tracking integration on the broader PV market.

  18. Numerical validation of MR-measurement-integrated simulation of blood flow in a cerebral aneurysm.

    PubMed

    Funamoto, Kenichi; Suzuki, Yoshitsugu; Hayase, Toshiyuki; Kosugi, Takashi; Isoda, Haruo

    2009-06-01

    This study proposes magnetic resonance (MR)-measurement-integrated (MR-MI) simulation, in which the difference between the computed velocity field and the phase-contrast MRI measurement data is fed back to the numerical simulation. The computational accuracy and the fundamental characteristics, such as steady characteristics and transient characteristics, of the MR-MI simulation were investigated by a numerical experiment. We dealt with reproduction of three-dimensional steady and unsteady blood flow fields in a realistic cerebral aneurysm developed at a bifurcation. The MR-MI simulation reduced the error derived from the incorrect boundary conditions in the blood flow in the cerebral aneurysm. For the reproduction of steady and unsteady standard solutions, the error of velocity decreased to 13% and to 22% in one cardiac cycle, respectively, compared with the ordinary simulation without feedback. Moreover, the application of feedback shortened the computational convergence, and thus the convergent solution and periodic solution were obtained within less computational time in the MR-MI simulation than that in the ordinary simulation. The dividing flow ratio toward the two outlets after bifurcation was well estimated owing to the improvement of computational accuracy. Furthermore, the MR-MI simulation yielded wall shear stress distribution on the cerebral aneurysm of the standard solution accurately and in detail. PMID:19350390

  19. An integral model for target tracking based on the use of a WSN.

    PubMed

    Calafate, Carlos T; Lino, Carlos; Diaz-Ramirez, Arnoldo; Cano, Juan-Carlos; Manzoni, Pietro

    2013-01-01

    The use of wireless sensor networks (WSN) in tracking applications is growing at a fast pace. In these applications, the sensor nodes discover, monitor and track an event or target object. A significant number of proposals relating the use of WSNs for target tracking have been published to date. However, they either focus on the tracking algorithm or on the communication protocol, and none of them address the problem integrally. In this paper, a comprehensive proposal for target detection and tracking is discussed. We introduce a tracking algorithm to detect and estimate a target location. Moreover, we introduce a low-overhead routing protocol to be used along with our tracking algorithm. The proposed algorithm has low computational complexity and has been designed considering the use of a mobile sink while generating minimal delay and packet loss. We also discuss the results of the evaluation of the proposed algorithms. PMID:23736849

  20. Quantitative cerebral perfusion assessment using microscope-integrated analysis of intraoperative indocyanine green fluorescence angiography versus positron emission tomography in superficial temporal artery to middle cerebral artery anastomosis

    PubMed Central

    Kobayashi, Shinya; Ishikawa, Tatsuya; Tanabe, Jun; Moroi, Junta; Suzuki, Akifumi

    2014-01-01

    Background: Intraoperative qualitative indocyanine green (ICG) angiography has been used in cerebrovascular surgery. Hyperperfusion may lead to neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. The purpose of this study is to quantitatively evaluate intraoperative cerebral perfusion using microscope-integrated dynamic ICG fluorescence analysis, and to assess whether this value predicts hyperperfusion syndrome (HPS) after STA-MCA anastomosis. Methods: Ten patients undergoing STA-MCA anastomosis due to unilateral major cerebral artery occlusive disease were included. Ten patients with normal cerebral perfusion served as controls. The ICG transit curve from six regions of interest (ROIs) on the cortex, corresponding to ROIs on positron emission tomography (PET) study, was recorded. Maximum intensity (IMAX), cerebral blood flow index (CBFi), rise time (RT), and time to peak (TTP) were evaluated. Results: RT/TTP, but not IMAX or CBFi, could differentiate between control and study subjects. RT/TTP correlated (|r| = 0.534-0.807; P < 0.01) with mean transit time (MTT)/MTT ratio in the ipsilateral to contralateral hemisphere by PET study. Bland–Altman analysis showed a wide limit of agreement between RT and MTT and between TTP and MTT. The ratio of RT before and after bypass procedures was significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.60 ± 0.032 and 0.80 ± 0.056, respectively; P = 0.017). The ratio of TTP was also significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.64 ± 0.081 and 0.85 ± 0.095, respectively; P = 0.017). Conclusions: Time-dependent intraoperative parameters from the ICG transit curve provide quantitative information regarding cerebral circulation time with quality and utility comparable to information obtained by PET. These parameters may help predict the occurrence of postoperative HPS. PMID

  1. Disconnected aging: cerebral white matter integrity and age-related differences in cognition.

    PubMed

    Bennett, I J; Madden, D J

    2014-09-12

    Cognition arises as a result of coordinated processing among distributed brain regions and disruptions to communication within these neural networks can result in cognitive dysfunction. Cortical disconnection may thus contribute to the declines in some aspects of cognitive functioning observed in healthy aging. Diffusion tensor imaging (DTI) is ideally suited for the study of cortical disconnection as it provides indices of structural integrity within interconnected neural networks. The current review summarizes results of previous DTI aging research with the aim of identifying consistent patterns of age-related differences in white matter integrity, and of relationships between measures of white matter integrity and behavioral performance as a function of adult age. We outline a number of future directions that will broaden our current understanding of these brain-behavior relationships in aging. Specifically, future research should aim to (1) investigate multiple models of age-brain-behavior relationships; (2) determine the tract-specificity versus global effect of aging on white matter integrity; (3) assess the relative contribution of normal variation in white matter integrity versus white matter lesions to age-related differences in cognition; (4) improve the definition of specific aspects of cognitive functioning related to age-related differences in white matter integrity using information processing tasks; and (5) combine multiple imaging modalities (e.g., resting-state and task-related functional magnetic resonance imaging; fMRI) with DTI to clarify the role of cerebral white matter integrity in cognitive aging. PMID:24280637

  2. Neurovascular coupling, cerebral white matter integrity, and response to cocoa in older people

    PubMed Central

    Hurwitz, Shelley; Salat, David H.; Greve, Douglas N.; Fisher, Naomi D.L.

    2013-01-01

    Objective: To investigate the relationship between neurovascular coupling and cognitive function in elderly individuals with vascular risk factors and to determine whether neurovascular coupling could be modified by cocoa consumption. Methods: Sixty older people (aged 72.9 ± 5.4 years) were studied in a parallel-arm, double-blind clinical trial of neurovascular coupling and cognition in response to 24 hours and 30 days of cocoa consumption. Cognitive measures included Mini-Mental State Examination and Trail Making Test A and B. Neurovascular coupling was measured from the beat-to-beat blood flow velocity responses in the middle cerebral arteries to the N-Back Task. In a subset of MRI-eligible participants, cerebral white matter structural integrity was also measured. Results: Neurovascular coupling was associated with Trails B scores (p = 0.002) and performance on the 2-Back Task. Higher neurovascular coupling was also associated with significantly higher fractional anisotropy in cerebral white matter hyperintensities (p = 0.02). Finally, 30 days of cocoa consumption was associated with increased neurovascular coupling (5.6% ± 7.2% vs −2.4% ± 4.8%; p = 0.001) and improved Trails B times (116 ± 78 seconds vs 167 ± 110 seconds; p = 0.007) in those with impaired neurovascular coupling at baseline. Conclusion: There is a strong correlation between neurovascular coupling and cognitive function, and both can be improved by regular cocoa consumption in individuals with baseline impairments. Better neurovascular coupling is also associated with greater white matter structural integrity. PMID:23925758

  3. 77 FR 64249 - Track Safety Standards; Improving Rail Integrity

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-19

    ... railroad safety.'' See 36 FR 20336. FRA envisioned the new Standards to be an evolving set of safety... the Standards in 1998. See 63 FR 34029, June 22, 1998; 63 FR 54078, Oct. 8, 1998. Pursuant to 49 U.S.C... track constructed with concrete crossties. See 76 FR 18073. FRA received two petitions...

  4. Morroniside Improves Microvascular Functional Integrity of the Neurovascular Unit after Cerebral Ischemia

    PubMed Central

    Sun, Fang-Ling; Cheng, Hua; Wang, Ying; Li, Lei; Xue, Jin-Long; Wang, Xiao-feng; Ai, Hou-Xi; Zhang, Li; Xu, Jing-dong

    2014-01-01

    Treating the vascular elements within the neurovascular unit is essential for protecting and repairing the brain after stroke. Acute injury on endothelial systems results in the disruption of blood-brain barrier (BBB), while post-ischemic angiogenesis plays an important role in delayed functional recovery. Here, we considered alterations in microvessel integrity to be targets for brain recovery, and tested the natural compound morroniside as a therapeutic approach to restore the vascular elements of injured tissue in a rat model of focal cerebral ischemia. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) model, and morroniside was then administered intragastrically once a day at doses of 30, 90, and 270 mg/kg. BBB integrity and associated factors were analyzed to identify cerebrovascular permeability 3 days after MCAO. The recruitment of endothelial progenitor cells (EPCs), the expression of angiogenic factors and the new vessel formation in the peri-infarct cortex of rats were examined 7 days after MCAO to identify the angiogenesis. We demonstrated that at 3 days post-ischemia, morroniside preserved neurovascular unit function by ameliorating BBB injury. By 7 days post-ischemia, morroniside amplified angiogenesis, in part by enhancing endothelial progenitor cell proliferation and expression of angiogenic factors. Morever, the increase in the amount of vWF+ vessels induced by ischemia could be extended to 28 days after administration of morroniside, indicating the crucial role of morroniside in angiogenesis during the chronic phase. Taken together, our findings suggested that morroniside might offer a novel therapeutic approach for promoting microvascular integrity recovery and provide a thoroughly new direction for stroke therapy. PMID:24979385

  5. Differenced Range Versus Integrated Doppler (DRVID) ionospheric analysis of metric tracking in the Tracking and Data Relay Satellite System (TDRSS)

    NASA Technical Reports Server (NTRS)

    Radomski, M. S.; Doll, C. E.

    1995-01-01

    The Differenced Range (DR) Versus Integrated Doppler (ID) (DRVID) method exploits the opposition of high-frequency signal versus phase retardation by plasma media to obtain information about the plasma's corruption of simultaneous range and Doppler spacecraft tracking measurements. Thus, DR Plus ID (DRPID) is an observable independent of plasma refraction, while actual DRVID (DR minus ID) measures the time variation of the path electron content independently of spacecraft motion. The DRVID principle has been known since 1961. It has been used to observe interplanetary plasmas, is implemented in Deep Space Network tracking hardware, and has recently been applied to single-frequency Global Positioning System user navigation This paper discusses exploration at the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) of DRVID synthesized from simultaneous two-way range and Doppler tracking for low Earth-orbiting missions supported by the Tracking and Data Relay Satellite System (TDRSS) The paper presents comparisons of actual DR and ID residuals and relates those comparisons to predictions of the Bent model. The complications due to the pilot tone influence on relayed Doppler measurements are considered. Further use of DRVID to evaluate ionospheric models is discussed, as is use of DRPID in reducing dependence on ionospheric modeling in orbit determination.

  6. An integrated software suite for surface-based analyses of cerebral cortex

    NASA Technical Reports Server (NTRS)

    Van Essen, D. C.; Drury, H. A.; Dickson, J.; Harwell, J.; Hanlon, D.; Anderson, C. H.

    2001-01-01

    The authors describe and illustrate an integrated trio of software programs for carrying out surface-based analyses of cerebral cortex. The first component of this trio, SureFit (Surface Reconstruction by Filtering and Intensity Transformations), is used primarily for cortical segmentation, volume visualization, surface generation, and the mapping of functional neuroimaging data onto surfaces. The second component, Caret (Computerized Anatomical Reconstruction and Editing Tool Kit), provides a wide range of surface visualization and analysis options as well as capabilities for surface flattening, surface-based deformation, and other surface manipulations. The third component, SuMS (Surface Management System), is a database and associated user interface for surface-related data. It provides for efficient insertion, searching, and extraction of surface and volume data from the database.

  7. Brainstem stimulation augments information integration in the cerebral cortex of desflurane-anesthetized rats

    PubMed Central

    Pillay, Siveshigan; Vizuete, Jeannette; Liu, Xiping; Juhasz, Gabor; Hudetz, Anthony G.

    2014-01-01

    States of consciousness have been associated with information integration in the brain as modulated by anesthesia and the ascending arousal system. The present study was designed to test the hypothesis that electrical stimulation of the oral part of the pontine reticular nucleus (PnO) can augment information integration in the cerebral cortex of anesthetized rats. Extracellular unit activity and local field potentials were recorded in freely moving animals from parietal association (PtA) and secondary visual (V2) cortices via chronically implanted microwire arrays at three levels of anesthesia produced by desflurane: 3.5, 4.5, and 6.0% (where 4.5% corresponds to that critical for the loss of consciousness). Information integration was characterized by integration (multiinformation) and interaction entropy, estimated from the statistical distribution of coincident spike patterns. PnO stimulation elicited electrocortical activation as indicated by the reductions in δ- and θ-band powers at the intermediate level of anesthesia. PnO stimulation augmented integration from 1.13 ± 0.03 to 6.12 ± 1.98 × 103 bits and interaction entropy from 0.44 ± 0.11 to 2.18 ± 0.72 × 103 bits; these changes were most consistent in the PtA at all desflurane concentrations. Stimulation of the retina with discrete light flashes after PnO stimulation elicited an additional 166 ± 25 and 92 ± 12% increase in interaction entropy in V2 during light and intermediate levels. The results suggest that the PnO may modulate spontaneous ongoing and sensory stimulus-related cortical information integration under anesthesia. PMID:24605091

  8. Feasibility study of an integrated optic switching center. [satellite tracking application

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The design of a high data rate switching center for a satellite tracking station is discussed. The feasibility of a switching network using an integrated switching matrix is assessed. The preferred integrated optical switching scheme was found to be an electro-optic Bragg diffraction switch. To ascertain the advantages of the integrated optics switching center, its properties are compared to those of opto-electronic and to electronics switching networks.

  9. Tracking skin integrity: a template for hospital and vendor collaboration.

    PubMed

    Kilpack, V; Campion, P; Stover, P; Wood, M E; Cocke, M W

    1996-04-01

    Collaborative endeavors are particularly attractive in a time when resources are under extensive demand, but for organizations to be successful at collaboration, many shared values and qualities are necessary. In 1992, a hospital and a vendor of therapeutic bed surfaces entered into a collaborative partnership to test clinical indicator ability to track skin care outcomes. The vendor contributed major funding for the project, a national database from which clinical indicators on pressure ulcers were determined, and data processing and analysis. The hospital provided project coordination, clinical knowledge, data collectors, and access to patients. The article describes the process, problems, and benefits of collaboration and underscores the need for a trusting psychological climate, strong mutual interest in the project, clearly stated goals with resources to meet them, collaborator consideration of each other as peers, and skill in tension management if collaboration is to be successful. PMID:8634467

  10. An integrated design for missile guidance/control/tracking system

    NASA Astrophysics Data System (ADS)

    Xu, Yefeng; Qiu, Haitao

    2008-10-01

    An integrated information system (IIS) which contains strapdown inertial navigation system (SINS), automatic pilot and terminal guidance seeker is proposed. Using rotating modulation approach, the performance of the low cost MEMS inertial sensor is improved by 20-30 times. The precision of the modulated MEMS gyro is available for strapdown navigation system and autopilot. The IIS gyros replace gimbal-based gyros are used in the line-of-sight (LOS) stabilization system. The seeker's LOS angular rate is estimated by combining the missile-fixed gyro information with gimbal coordinate rate information. The indirect LOS stabilization control loop is elaborately designed according to the gimbal kinematical relationship and dynamics models. The study and analysis results show that the compensation torque is available to null the disturbance and make the LOS stabilization. The proposed IIS saves two sets of gyros and make the SINS, autopilot, seeker integrated designing. It owns many advantages such as compact configuration, prominent low cost etc.

  11. Integration of Off-Track Sonic Boom Analysis in Conceptual Design of Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Ordaz, Irian; Li, Wu

    2011-01-01

    A highly desired capability for the conceptual design of aircraft is the ability to rapidly and accurately evaluate new concepts to avoid adverse trade decisions that may hinder the development process in the later stages of design. Evaluating the robustness of new low-boom concepts is important for the conceptual design of supersonic aircraft. Here, robustness means that the aircraft configuration has a low-boom ground signature at both under- and off-track locations. An integrated process for off-track boom analysis is developed to facilitate the design of robust low-boom supersonic aircraft. The integrated off-track analysis can also be used to study the sonic boom impact and to plan future flight trajectories where flight conditions and ground elevation might have a significant effect on ground signatures. The key enabler for off-track sonic boom analysis is accurate computational fluid dynamics (CFD) solutions for off-body pressure distributions. To ensure the numerical accuracy of the off-body pressure distributions, a mesh study is performed with Cart3D to determine the mesh requirements for off- body CFD analysis and comparisons are made between the Cart3D and USM3D results. The variations in ground signatures that result from changes in the initial location of the near-field waveform are also examined. Finally, a complete under- and off-track sonic boom analysis is presented for two distinct supersonic concepts to demonstrate the capability of the integrated analysis process.

  12. Statistical integration of tracking and vessel survey data to incorporate life history differences in habitat models.

    PubMed

    Yamamoto, Takashi; Watanuki, Yutaka; Hazen, Elliott L; Nishizawa, Bungo; Sasaki, Hiroko; Takahashi, Akinori

    2015-12-01

    Habitat use is often examined at a species or population level, but patterns likely differ within a species, as a function of the sex, breeding colony, and current breeding status of individuals. Hence, within-species differences should be considered in habitat models when analyzing and predicting species distributions, such as predicted responses to expected climate change scenarios. Also, species' distribution data obtained by different methods (vessel-survey and individual tracking) are often analyzed separately rather than integrated to improve predictions. Here, we eventually fit generalized additive models for Streaked Shearwaters Calonectris leuconelas using tracking data from two different breeding colonies in the Northwestern Pacific and visual observer data collected during a research cruise off the coast of western Japan. The tracking-based models showed differences among patterns of relative density distribution as a function of life history category (colony, sex, and breeding conditions). The integrated tracking-based and vessel-based bird count model incorporated ecological states rather than predicting a single surface for the entire species. This study highlights both the importance of including ecological and life history data and integrating multiple data types (tag-based tracking and vessel count) when examining species-environment relationships, ultimately advancing the capabilities of species distribution models. PMID:26910963

  13. Characterization of multiple-bit errors from single-ion tracks in integrated circuits

    NASA Technical Reports Server (NTRS)

    Zoutendyk, J. A.; Edmonds, L. D.; Smith, L. S.

    1989-01-01

    The spread of charge induced by an ion track in an integrated circuit and its subsequent collection at sensitive nodal junctions can cause multiple-bit errors. The authors have experimentally and analytically investigated this phenomenon using a 256-kb dynamic random-access memory (DRAM). The effects of different charge-transport mechanisms are illustrated, and two classes of ion-track multiple-bit error clusters are identified. It is demonstrated that ion tracks that hit a junction can affect the lateral spread of charge, depending on the nature of the pull-up load on the junction being hit. Ion tracks that do not hit a junction allow the nearly uninhibited lateral spread of charge.

  14. Sight-Reading Expertise: Cross-Modality Integration Investigated Using Eye Tracking

    ERIC Educational Resources Information Center

    Drai-Zerbib, Veronique; Baccino, Thierry; Bigand, Emmanuel

    2012-01-01

    It is often said that experienced musicians are capable of hearing what they read (and vice versa). This suggests that they are able to process and to integrate multimodal information. The present study investigates this issue with an eye-tracking technique. Two groups of musicians chosen on the basis of their level of expertise (experts,…

  15. Information Technology: Making It All Fit. Track II: Managing Technologies Integration.

    ERIC Educational Resources Information Center

    CAUSE, Boulder, CO.

    Nine papers from the 1988 CAUSE conference's Track II, Managing Technologies Integration, are presented. They include: "Computing in the '90s--Will We Be Ready for the Applications Needed?" (Stephen Patrick); "Glasnost, The Era of 'Openness'" (Bernard W. Gleason); "Academic and Administrative Computing: Are They Really Merging?" (Samuel J. Plice);…

  16. Amplitude-integrated electroencephalographic activity and middle cerebral artery Doppler flow measurements in preterm small for gestational age infants.

    PubMed

    Kolsuz, Leyla Daban; Topcuoglu, Sevilay; Gursoy, Tugba; Karatekin, Güner; Ovali, H Fahri

    2015-03-01

    Amplitude-integrated encephalography (EEG) is frequently used in neonatal intensive care units to monitor brain functions. Its bedside application and easy interpretation are the most important features. Brain development of small for gestational age infants can be affected by intrauterine chronic hypoxia. The current study aimed to evaluate cerebral functions of small for gestational age infants by means of amplitude-integrated EEG. Thirty- to 34-week-old 22 small for gestational age and 27 appropriate for gestational age preterm infants were included in the study. The mode of delivery, gender, birth weight, and Apgar scores of the patients were recorded. Following middle cerebral artery mean velocity measurement with cranial Doppler at the 24th hour of birth, an amplitude-integrated EEG recording was performed on all infants, for a period of 4 to 24 hours. Small for gestational age infants had significantly higher middle cerebral artery mean velocity than appropriate for gestational age infants (21.09 ± 4.25 vs 17.8 ± 4.07; P = .029). The amplitude-integrated EEG recordings showed lower "lower border of quiet sleep" and total Burdjalov score in small for gestational age infants when compared with appropriate for gestational age infants (2.5 [1-3.25] µV vs 3 [2.75-4] µV; P = .04, 8 [6-10], 9 [9-11]; P = .04, respectively). Increased middle cerebral artery blood flow observed in small for gestational age infants might be a marker of chronic intrauterine hypoxia to which these infants were exposed. These infants demonstrated a more immature pattern of amplitude-integrated EEG. PMID:25296921

  17. Integrated design and management of complex and fast track projects

    NASA Astrophysics Data System (ADS)

    Mancini, Dario

    2003-02-01

    Modern scientific and technological projects are increasingly in competition over scientific aims, technological innovation, performance, time and cost. They require a dedicated and innovative organization able to satisfy contemporarily various technical and logistic constraints imposed by the final user, and guarantee the satisfaction of technical specifications, identified on the basis of scientific aims. In order to satisfy all the above, the management has to be strategically innovative and intuitive, by removing, first of all, the bottlenecks that are pointed out, usually only at the end of the projects, as the causes of general dissatisfaction. More than 30 years spent working on complex multidisciplinary systems and 20 years of formative experience in managing contemporarily both scientific, technological and industrial projects have given the author the possibility to study, test and validate strategies for parallel project management and integrated design, merged in a sort of unique optimized task, using the newly-coined word "Technomethodology". The paper highlights useful information to be taken into consideration during project organization to minimize the program deviations from the expected goals and describe some of the basic meanings of this new advanced method that is the key for parallel successful management of multiple and interdisciplinary activities.

  18. Cue Recognition and Integration – Eye Tracking Evidence of Processing Differences in Sentence Comprehension in Aphasia

    PubMed Central

    Schumacher, Rahel; Cazzoli, Dario; Eggenberger, Noëmi; Preisig, Basil; Nef, Tobias; Nyffeler, Thomas; Gutbrod, Klemens; Annoni, Jean-Marie; Müri, René M.

    2015-01-01

    Purpose We aimed at further elucidating whether aphasic patients’ difficulties in understanding non-canonical sentence structures, such as Passive or Object-Verb-Subject sentences, can be attributed to impaired morphosyntactic cue recognition, and to problems in integrating competing interpretations. Methods A sentence-picture matching task with canonical and non-canonical spoken sentences was performed using concurrent eye tracking. Accuracy, reaction time, and eye tracking data (fixations) of 50 healthy subjects and 12 aphasic patients were analysed. Results Patients showed increased error rates and reaction times, as well as delayed fixation preferences for target pictures in non-canonical sentences. Patients’ fixation patterns differed from healthy controls and revealed deficits in recognizing and immediately integrating morphosyntactic cues. Conclusion Our study corroborates the notion that difficulties in understanding syntactically complex sentences are attributable to a processing deficit encompassing delayed and therefore impaired recognition and integration of cues, as well as increased competition between interpretations. PMID:26562795

  19. Sensorless control of salient PMSM with adaptive integrator and resistance online identification using strong tracking filter

    NASA Astrophysics Data System (ADS)

    Ma, Shaokang; Wu, Peijun; Ji, Jinhu; Li, Xuchun

    2016-02-01

    This article presents a sensorless control approach of salient PMSM with an online parameter identifier. Adaptive Integrator is proposed and utilised for the estimation of active flux and rotor position. As a result, integrator overflow caused by DC offset is avoided. Meanwhile, an online stator resistance identification algorithm using strong tracking filter is employed, and the identified stator resistance is fed back to the estimating algorithm. Thus, the estimating algorithm can calculate the rotor position correctly. Simulations and experimental results validate the feasibility of both adaptive integrator and the parameter identification method.

  20. A precise integration method for solving coupled vehicle-track dynamics with nonlinear wheel-rail contact

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Gao, Q.; Tan, S. J.; Zhong, W. X.

    2012-10-01

    A new method is proposed as a solution for the large-scale coupled vehicle-track dynamic model with nonlinear wheel-rail contact. The vehicle is simplified as a multi-rigid-body model, and the track is treated as a three-layer beam model. In the track model, the rail is assumed to be an Euler-Bernoulli beam supported by discrete sleepers. The vehicle model and the track model are coupled using Hertzian nonlinear contact theory, and the contact forces of the vehicle subsystem and the track subsystem are approximated by the Lagrange interpolation polynomial. The response of the large-scale coupled vehicle-track model is calculated using the precise integration method. A more efficient algorithm based on the periodic property of the track is applied to calculate the exponential matrix and certain matrices related to the solution of the track subsystem. Numerical examples demonstrate the computational accuracy and efficiency of the proposed method.

  1. In vivo tracking of human adipose-derived stem cells labeled with ferumoxytol in rats with middle cerebral artery occlusion by magnetic resonance imaging

    PubMed Central

    Yin, Yan; Zhou, Xiang; Guan, Xin; Liu, Yang; Jiang, Chang-bin; Liu, Jing

    2015-01-01

    Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide approved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-derived stem cells labeled with ferumoxytol in middle cerebral artery occlusion-injured rats by 3.0 T MRI in vivo. 1 × 104 human adipose-derived stem cells labeled with ferumoxytol-heparin-protamine were transplanted into the brains of rats with middle cerebral artery occlusion. Neurologic impairment was scored at 1, 7, 14, and 28 days after transplantation. T2-weighted imaging and enhanced susceptibility-weighted angiography were used to observe transplanted cells. Results of imaging tests were compared with results of Prussian blue staining. The modified neurologic impairment scores were significantly lower in rats transplanted with cells at all time points except 1 day post-transplantation compared with rats without transplantation. Regions with hypointense signals on T2-weighted and enhanced susceptibility-weighted angiography images corresponded with areas stained by Prussian blue, suggesting the presence of superparamagnetic iron oxide particles within the engrafted cells. Enhanced susceptibility-weighted angiography image exhibited better sensitivity and contrast in tracing ferumoxytol-heparin-protamine-labeled human adipose-derived stem cells compared with T2-weighted imaging in routine MRI. PMID:26199607

  2. Multileaf collimator tracking integrated with a novel x-ray imaging system and external surrogate monitoring

    NASA Astrophysics Data System (ADS)

    Krauss, Andreas; Fast, Martin F.; Nill, Simeon; Oelfke, Uwe

    2012-04-01

    We have previously developed a tumour tracking system, which adapts the aperture of a Siemens 160 MLC to electromagnetically monitored target motion. In this study, we exploit the use of a novel linac-mounted kilovoltage x-ray imaging system for MLC tracking. The unique in-line geometry of the imaging system allows the detection of target motion perpendicular to the treatment beam (i.e. the directions usually featuring steep dose gradients). We utilized the imaging system either alone or in combination with an external surrogate monitoring system. We equipped a Siemens ARTISTE linac with two flat panel detectors, one directly underneath the linac head for motion monitoring and the other underneath the patient couch for geometric tracking accuracy assessments. A programmable phantom with an embedded metal marker reproduced three patient breathing traces. For MLC tracking based on x-ray imaging alone, marker position was detected at a frame rate of 7.1 Hz. For the combined external and internal motion monitoring system, a total of only 85 x-ray images were acquired prior to or in between the delivery of ten segments of an IMRT beam. External motion was monitored with a potentiometer. A correlation model between external and internal motion was established. The real-time component of the MLC tracking procedure then relied solely on the correlation model estimations of internal motion based on the external signal. Geometric tracking accuracies were 0.6 mm (1.1 mm) and 1.8 mm (1.6 mm) in directions perpendicular and parallel to the leaf travel direction for the x-ray-only (the combined external and internal) motion monitoring system in spite of a total system latency of ˜0.62 s (˜0.51 s). Dosimetric accuracy for a highly modulated IMRT beam-assessed through radiographic film dosimetry-improved substantially when tracking was applied, but depended strongly on the respective geometric tracking accuracy. In conclusion, we have for the first time integrated MLC tracking

  3. Integration of the low-energy particle track simulation code in Geant4

    NASA Astrophysics Data System (ADS)

    Arce, Pedro; Muñoz, Antonio; Moraleda, Montserrat; Gomez Ros, José María; Blanco, Fernando; Perez, José Manuel; García, Gustavo

    2015-08-01

    The Low-Energy Particle Track Simulation code (LEPTS) is a Monte Carlo code developed to simulate the damage caused by radiation at molecular level. The code is based on experimental data of scattering cross sections, both differential and integral, and energy loss data, complemented with theoretical calculations. It covers the interactions of electrons and positrons from energies of 10 keV down to 0.1 eV in different biologically relevant materials. In this article we briefly mention the main characteristics of this code and we present its integration within the Geant4 Monte Carlo toolkit.

  4. Integration of Three-Dimensional Rotational Angiography in Radiosurgical Treatment Planning of Cerebral Arteriovenous Malformations

    SciTech Connect

    Conti, Alfredo; Pontoriero, Antonio; Farago, Giuseppe; Midili, Federica; Siragusa, Carmelo; Granata, Francesca; Pitrone, Antonio; De Renzis, Costantino; Longo, Marcello; Tomasello, Francesco

    2011-11-01

    Purpose: Accuracy in delineating the target volume is a major issue for successful stereotactic radiosurgery for arteriovenous malformations. The aim of the present study was to describe a method to integrate three-dimensional (3D) rotational angiography ( (3DRA)) into CyberKnife treatment planning and to investigate its potential advantages compared with computed tomography angiography (CTA) and magnetic resonance angiography. Methods and Materials: A total of 20 patients with a diagnosis of cerebral arteriovenous malformation were included in the present study. All patients underwent multislice computed tomography and 3D-volumetric CTA, (3DRA), and 3D magnetic resonance angiography. The contouring of the target and critical volumes was done separately using CTA and thereafter directly using (3DRA). The composite, conjoint, and disjoint volumes were measured. Results: The use of CTA or (3DRA) resulted in significant differences in the target and critical volumes. The target volume averaged 3.49 {+-} 3.01 mL measured using CTA and 3.26 {+-} 2.93 mL measured using (3DRA), for a difference of 8% (p < .05). The conjoint and disjoint volume analysis showed an 88% volume overlap. The qualitative evaluation showed that the excess volume obtained using CTA was mostly tissue surrounding the nidus and venous structures. The mean contoured venous volume was 0.67 mL measured using CTA and 0.88 mL (range, 0.1-2.7) measured using (3DRA) (p < .05). Conclusions: (3DRA) is a volumetric angiographic study that can be integrated into computer-based treatment planning. Although whether (3DRA) provides superior accuracy has not yet been proved, its high spatial resolution is attractive and offers a superior 3D view. This allows a better 3D understanding of the target volume and distribution of the radiation doses within the volume. Additional technical efforts to improve the temporal resolution and the development of software tools aimed at improving the performance of 3D contouring

  5. Computed tomographic angiography of the superficial cerebral venous anastomosis based on volume rendering, multi-planar reconstruction, and integral imaging display.

    PubMed

    Fang, Qiong; Chen, Feng; Jiang, Anhong; Huang, Yanping; Deng, Xuefei

    2015-12-01

    As damage to the superficial cerebral venous anastomosis may create catastrophic complications even after successful surgery, it is important to visualize and determine the normal features of the venous anastomosis with computed tomographic angiography. A total of 90 patients underwent a 64-detector row helical CT scan of head. The superficial cerebral venous anastomosis was reconstructed by volume rendering, multi-planar reconstruction, and integral display algorithm. In particular, we examined the vein of Trolard, the vein of Labbe, and the vein of Sylvian, in order to analyze the venous anastomosis. The superficial cerebral venous anastomosis varied across different individuals, and in this study, six types of anastomosis were found. In 28 % of patients, no venous anastomosis was found in the unilateral cerebral hemisphere. The display rate of the vein of Trolard, the vein of Labbe, and the vein of Sylvian in contributing to venous anastomosis was 70, 80, and 91 %, respectively. The number of vein of Trolard and vein of Labbe on the left side was greater than that of those on the right side. We implemented the 64-detector row helical CT as a rapid and noninvasive method to investigate the superficial cerebral venous anastomosis in our group of patients. We performed substantial image processing for the visualization of the superficial cerebral venous anastomosis; this would not only enable the early diagnosis of cerebral venous disease, but also protect the cerebral vein during neurosurgical intervention. PMID:26577709

  6. Off-policy integral reinforcement learning optimal tracking control for continuous-time chaotic systems

    NASA Astrophysics Data System (ADS)

    Wei, Qing-Lai; Song, Rui-Zhuo; Sun, Qiu-Ye; Xiao, Wen-Dong

    2015-09-01

    This paper estimates an off-policy integral reinforcement learning (IRL) algorithm to obtain the optimal tracking control of unknown chaotic systems. Off-policy IRL can learn the solution of the HJB equation from the system data generated by an arbitrary control. Moreover, off-policy IRL can be regarded as a direct learning method, which avoids the identification of system dynamics. In this paper, the performance index function is first given based on the system tracking error and control error. For solving the Hamilton-Jacobi-Bellman (HJB) equation, an off-policy IRL algorithm is proposed. It is proven that the iterative control makes the tracking error system asymptotically stable, and the iterative performance index function is convergent. Simulation study demonstrates the effectiveness of the developed tracking control method. Project supported by the National Natural Science Foundation of China (Grant Nos. 61304079 and 61374105), the Beijing Natural Science Foundation, China (Grant Nos. 4132078 and 4143065), the China Postdoctoral Science Foundation (Grant No. 2013M530527), the Fundamental Research Funds for the Central Universities, China (Grant No. FRF-TP-14-119A2), and the Open Research Project from State Key Laboratory of Management and Control for Complex Systems, China (Grant No. 20150104).

  7. Efficient integration of spectral features for vehicle tracking utilizing an adaptive sensor

    NASA Astrophysics Data System (ADS)

    Uzkent, Burak; Hoffman, Matthew J.; Vodacek, Anthony

    2015-03-01

    Object tracking in urban environments is an important and challenging problem that is traditionally tackled using visible and near infrared wavelengths. By inserting extended data such as spectral features of the objects one can improve the reliability of the identification process. However, huge increase in data created by hyperspectral imaging is usually prohibitive. To overcome the complexity problem, we propose a persistent air-to-ground target tracking system inspired by a state-of-the-art, adaptive, multi-modal sensor. The adaptive sensor is capable of providing panchromatic images as well as the spectra of desired pixels. This addresses the data challenge of hyperspectral tracking by only recording spectral data as needed. Spectral likelihoods are integrated into a data association algorithm in a Bayesian fashion to minimize the likelihood of misidentification. A framework for controlling spectral data collection is developed by incorporating motion segmentation information and prior information from a Gaussian Sum filter (GSF) movement predictions from a multi-model forecasting set. An intersection mask of the surveillance area is extracted from OpenStreetMap source and incorporated into the tracking algorithm to perform online refinement of multiple model set. The proposed system is tested using challenging and realistic scenarios generated in an adverse environment.

  8. Adaptive optics scanning laser ophthalmoscope with integrated wide-field retinal imaging and tracking

    PubMed Central

    Ferguson, R. Daniel; Zhong, Zhangyi; Hammer, Daniel X.; Mujat, Mircea; Patel, Ankit H.; Deng, Cong; Zou, Weiyao; Burns, Stephen A.

    2010-01-01

    We have developed a new, unified implementation of the adaptive optics scanning laser ophthalmoscope (AOSLO) incorporating a wide-field line-scanning ophthalmoscope (LSO) and a closed-loop optical retinal tracker. AOSLO raster scans are deflected by the integrated tracking mirrors so that direct AOSLO stabilization is automatic during tracking. The wide-field imager and large-spherical-mirror optical interface design, as well as a large-stroke deformable mirror (DM), enable the AOSLO image field to be corrected at any retinal coordinates of interest in a field of >25 deg. AO performance was assessed by imaging individuals with a range of refractive errors. In most subjects, image contrast was measurable at spatial frequencies close to the diffraction limit. Closed-loop optical (hardware) tracking performance was assessed by comparing sequential image series with and without stabilization. Though usually better than 10 μm rms, or 0.03 deg, tracking does not yet stabilize to single cone precision but significantly improves average image quality and increases the number of frames that can be successfully aligned by software-based post-processing methods. The new optical interface allows the high-resolution imaging field to be placed anywhere within the wide field without requiring the subject to re-fixate, enabling easier retinal navigation and faster, more efficient AOSLO montage capture and stitching. PMID:21045887

  9. Enable Web-Based Tracking and Guiding by Integrating Location-Awareness with the World Wide Web

    ERIC Educational Resources Information Center

    Zhou, Rui

    2008-01-01

    Purpose: The aim of this research is to enable web-based tracking and guiding by integrating location-awareness with the Worldwide Web so that the users can use various location-based applications without installing extra software. Design/methodology/approach: The concept of web-based tracking and guiding is introduced and the relevant issues are…

  10. A Magnetic Tracking System based on Highly Sensitive Integrated Hall Sensors

    NASA Astrophysics Data System (ADS)

    Schlageter, Vincent; Drljaca, Predrag; Popovic, Radivoje S.; KuČERA, Pavel

    A tracking system with five degrees of freedom based on a 2D-array of 16 Hall sensors and a permanent magnet is presented in this paper. The sensitivity of the Hall sensors is increased by integrated micro- and external macro-flux-concentrators. Detection distance larger than 20cm (during one hour without calibration) is achieved using a magnet of 0.2cm3. This corresponds to a resolution of the sensors of 0.05µTrms. The position and orientation of the marker is displayed in real time at least 20 times per second. The sensing system is small enough to be hand-held and can be used in a normal environment. This presented tracking system has been successfully applied to follow a small swallowed magnet through the entire human digestive tube. This approach is extremely promising as a new non-invasive diagnostic technique in gastro-enterology.

  11. Cerebral Palsy

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Cerebral Palsy KidsHealth > For Teens > Cerebral Palsy Print A A ... do just what everyone else does. What Is Cerebral Palsy? Cerebral palsy (CP) is a disorder of the ...

  12. CISUS: an integrated 3D ultrasound system for IGT using a modular tracking API

    NASA Astrophysics Data System (ADS)

    Boctor, Emad M.; Viswanathan, Anand; Pieper, Steve; Choti, Michael A.; Taylor, Russell H.; Kikinis, Ron; Fichtinger, Gabor

    2004-05-01

    Ultrasound has become popular in clinical/surgical applications, both as the primary image guidance modality and also in conjunction with other modalities like CT or MRI. Three dimensional ultrasound (3DUS) systems have also demonstrated usefulness in image-guided therapy (IGT). At the same time, however, current lack of open-source and open-architecture multi-modal medical visualization systems prevents 3DUS from fulfilling its potential. Several stand-alone 3DUS systems, like Stradx or In-Vivo exist today. Although these systems have been found to be useful in real clinical setting, it is difficult to augment their functionality and integrate them in versatile IGT systems. To address these limitations, a robotic/freehand 3DUS open environment (CISUS) is being integrated into the 3D Slicer, an open-source research tool developed for medical image analysis and surgical planning. In addition, the system capitalizes on generic application programming interfaces (APIs) for tracking devices and robotic control. The resulting platform-independent open-source system may serve as a valuable tool to the image guided surgery community. Other researchers could straightforwardly integrate the generic CISUS system along with other functionalities (i.e. dual view visualization, registration, real-time tracking, segmentation, etc) to rapidly create their medical/surgical applications. Our current driving clinical application is robotically assisted and freehand 3DUS-guided liver ablation, which is fully being integrated under the CISUS-3D Slicer. Initial functionality and pre-clinical feasibility are demonstrated on phantom and ex-vivo animal models.

  13. Bridging the Gap: Supporting Translational Research Careers Through an Integrated Research Track Within Residency Training

    PubMed Central

    Arbuckle, Melissa R.; Gordon, Joshua A.; Pincus, Harold A.; Oquendo, Maria A.

    2013-01-01

    In the setting of traditional residency training programs, physician–scientists are often limited in their ability to pursue research training goals while meeting clinical training requirements. This creates a gap in research training at a critical developmental stage. In response, Columbia University Medical Center’s Department of Psychiatry, in partnership with the New York State Psychiatric Institute, has created a formal Research Track Program (RTP) for psychiatry residents so that interested individuals can maintain their attention on research training during formative residency years. Clinical and research training are integrated through core clinical rotations on research units. With protected research time and clear developmental milestones for each year of training, the RTP allows research track residents to meet both clinical and research training goals while maintaining a healthy work–life balance. In coordination with existing postdoctoral research fellowship programs, research track residents can effectively jump-start fellowship training with advanced course work and consistent, continuous mentorship bridging residency and fellowship years. A key element of the program is its provision of core training in research literacy and extensive research opportunities for all residents, stimulating research interest across the whole residency program. Supported by the National Institutes of Health and a private foundation, this RTP capitalizes on a unique academic–private partnership to address many of the challenges facing physician–scientists. By integrating clinical and research exposures and offering protected research time, careful mentoring, and financial resources, the program aims to further the development of those most poised to establish careers in translational research. PMID:23619070

  14. ArF scanner performance improvement by using track integrated CD optimization

    NASA Astrophysics Data System (ADS)

    Huang, Jacky; Yu, Shinn-Sheng; Ke, Chih-Ming; Wu, Timothy; Wang, Yu-Hsi; Gau, Tsai-Sheng; Wang, Dennis; Li, Allen; Yang, Wenge; Kaoru, Araki

    2006-03-01

    In advanced semiconductor processing, shrinking CD is one of the main objectives when moving to the next generation technology. Improving CD uniformity (CDU) with shrinking CD is one of the biggest challenges. From ArF lithography CD error budget analysis, PEB (post exposure bake) contributes more than 40% CD variations. It turns out that hot plate performance such as CD matching and within-plate temperature control play key roles in litho cell wafer per hour (WPH). Traditionally wired or wireless thermal sensor wafers were used to match and optimize hot plates. However, sensor-to-sensor matching and sensor data quality vs. sensor lifetime or sensor thermal history are still unknown. These concerns make sensor wafers more suitable for coarse mean-temperature adjustment. For precise temperature adjustment, especially within-hot-plate temperature uniformity, using CD instead of sensor wafer temperature is a better and more straightforward metrology to calibrate hot plates. In this study, we evaluated TEL clean track integrated optical CD metrology (IM) combined with TEL CD Optimizer (CDO) software to improve 193-nm resist within-wafer and wafer-to-wafer CD uniformity. Within-wafer CD uniformity is mainly affected by the temperature non-uniformity on the PEB hot plate. Based on CD and PEB sensitivity of photo resists, a physical model has been established to control the CD uniformity through fine-tuning PEB temperature settings. CD data collected by track integrated CD metrology was fed into this model, and the adjustment of PEB setting was calculated and executed through track internal APC system. This auto measurement, auto feed forward, auto calibration and auto adjustment system can reduce the engineer key-in error and improve the hot plate calibration cycle time. And this PEB auto calibration system can easily bring hot-plate-to-hot-plate CD matching to within 0.5nm and within-wafer CDU (3σ) to less than 1.5nm.

  15. Integration of trans-esophageal echocardiography with magnetic tracking technology for cardiac interventions

    NASA Astrophysics Data System (ADS)

    Moore, John T.; Wiles, Andrew D.; Wedlake, Chris; Bainbridge, Daniel; Kiaii, Bob; Trejos, Ana Luisa; Patel, Rajni; Peters, Terry M.

    2010-02-01

    Trans-esophageal echocardiography (TEE) is a standard component of patient monitoring during most cardiac surgeries. In recent years magnetic tracking systems (MTS) have become sufficiently robust to function effectively in appropriately structured operating room environments. The ability to track a conventional multiplanar 2D TEE transducer in 3D space offers incredible potential by greatly expanding the cumulative field of view of cardiac anatomy beyond the limited field of view provided by 2D and 3D TEE technology. However, there is currently no TEE probe manufactured with MTS technology embedded in the transducer, which means sensors must be attached to the outer surface of the TEE. This leads to potential safety issues for patients, as well as potential damage to the sensor during procedures. This paper presents a standard 2D TEE probe fully integrated with MTS technology. The system is evaluated in an environment free of magnetic and electromagnetic disturbances, as well as a clinical operating room in the presence of a da Vinci robotic system. Our first integrated TEE device is currently being used in animal studies for virtual reality-enhanced ultrasound guidance of intracardiac surgeries, while the "second generation" TEE is in use in a clinical operating room as part of a project to measure perioperative heart shift and optimal port placement for robotic cardiac surgery. We demonstrate excellent system accuracy for both applications.

  16. Dimethyl fumarate attenuates cerebral edema formation by protecting the blood-brain barrier integrity.

    PubMed

    Kunze, Reiner; Urrutia, Andrés; Hoffmann, Angelika; Liu, Hui; Helluy, Xavier; Pham, Mirko; Reischl, Stefan; Korff, Thomas; Marti, Hugo H

    2015-04-01

    Brain edema is a hallmark of various neuropathologies, but the underlying mechanisms are poorly understood. We aim to characterize how tissue hypoxia, together with oxidative stress and inflammation, leads to capillary dysfunction and breakdown of the blood-brain barrier (BBB). In a mouse stroke model we show that systemic treatment with dimethyl fumarate (DMF), an antioxidant drug clinically used for psoriasis and multiple sclerosis, significantly prevented edema formation in vivo. Indeed, DMF stabilized the BBB by preventing disruption of interendothelial tight junctions and gap formation, and decreased matrix metalloproteinase activity in brain tissue. In vitro, DMF directly sustained endothelial tight junctions, inhibited inflammatory cytokine expression, and attenuated leukocyte transmigration. We also demonstrate that these effects are mediated via activation of the redox sensitive transcription factor NF-E2 related factor 2 (Nrf2). DMF activated the Nrf2 pathway as shown by up-regulation of several Nrf2 target genes in the brain in vivo, as well as in cerebral endothelial cells and astrocytes in vitro, where DMF also increased protein abundance of nuclear Nrf2. Finally, Nrf2 knockdown in endothelial cells aggravated subcellular delocalization of tight junction proteins during ischemic conditions, and attenuated the protective effect exerted by DMF. Overall, our data suggest that DMF protects from cerebral edema formation during ischemic stroke by targeting interendothelial junctions in an Nrf2-dependent manner, and provide the basis for a completely new approach to treat brain edema. PMID:25725349

  17. Inertial and GPS data integration for positioning and tracking of GPR

    NASA Astrophysics Data System (ADS)

    Chicarella, Simone; D'Alvano, Alessandro; Ferrara, Vincenzo; Frezza, Fabrizio; Pajewski, Lara

    2015-04-01

    Nowadays many applications and studies use a Global Positioning System (GPS) to integrate Ground-Penetrating Radar (GPR) data [1-2]. The aim is the production of detailed detection maps that are geo-referenced and superimposable on geographic maps themes. GPS provides data to determine static positioning, and to track the mobile detection system path on the land. A low-cost standard GPS, like GPS-622R by RF Solutions Ltd, allows accuracy around 2.5 m CEP (Circular Error Probability), and a maximum update rate of 10 Hz. These accuracy and update rate are satisfying values when we evaluate positioning datum, but they are unsuitable for precision tracking of a speedy-mobile GPR system. In order to determine the relative displacements with respect to an initial position on the territory, an Inertial Measurement Unit (IMU) can be used. Some inertial-system applications for GPR tracking have been presented in recent studies [3-4]. The integration of both GPS and IMU systems is the aim of our work, in order to increase GPR applicability, e.g. the case of a GPR mounted on an unmanned aerial vehicle for the detection of people buried under avalanches [5]. In this work, we will present the design, realization and experimental characterization of our electronic board that includes GPS-622R and AltIMU-10 v3 by Pololu. The latter comprises an inertial-measurement unit and an altimeter. In particular, the IMU adopts L3GD20 gyro and LSM303D accelerometer and magnetometer; the digital barometer LPS331AP provides data for altitude evaluation. The prototype of our system for GPR positioning and tracking is based on an Arduino microcontroller board. Acknowledgement This work benefited from networking activities carried out within the EU funded COST Action TU1208 'Civil Engineering Applications of Ground Penetrating Radar. ' References [1] M. Solla, X. Núñez-Nieto, M. Varela-González, J. Martínez-Sánchez, and P. Arias, 'GPR for Road Inspection: georeferencing and efficient

  18. Integrative tracking methods elucidate the evolutionary dynamics of a migratory divide

    PubMed Central

    Alvarado, Allison H; Fuller, Trevon L; Smith, Thomas B

    2014-01-01

    Migratory divides, the boundary between adjacent bird populations that migrate in different directions, are of considerable interest to evolutionary biologists because of their alleged role in speciation of migratory birds. However, the small size of many passerines has traditionally limited the tools available to track populations and as a result, restricted our ability to study how reproductive isolation might occur across a divide. Here, we integrate multiple approaches by using genetic, geolocator, and morphological data to investigate a migratory divide in hermit thrushes (Catharus guttatus). First, high genetic divergence between migratory groups indicates the divide is a region of secondary contact between historically isolated populations. Second, despite low sample sizes, geolocators reveal dramatic differences in overwintering locations and migratory distance of individuals from either side of the divide. Third, a diagnostic genetic marker that proved useful for tracking a key population suggests a likely intermediate nonbreeding location of birds from the hybrid zone. This finding, combined with lower return rates from this region, is consistent with comparatively lower fitness of hybrids, which is possibly due to this intermediate migration pattern. We discuss our results in the context of reproductive isolating mechanisms associated with migration patterns that have long been hypothesized to promote divergence across migratory divides. PMID:25535561

  19. Symplectic tracking and compensation of dynamic field integrals in complex undulator structures

    NASA Astrophysics Data System (ADS)

    Bahrdt, Johannes; Wüstefeld, Godehard

    2011-04-01

    In first approximation storage ring multipole magnets are described as simple two-dimensional magnet structures and many linear and nonlinear beam optic features of a magnet lattice can already be derived from this model. In contrast, undulators, and in particular variably polarizing devices, employ complicated three-dimensional magnetic fields which may have a severe impact on the electron beam, in particular, in low energy third generation storage rings. A Taylor expanded generating function method is presented to generate a fast, flexible, and symplectic mapping routine for particle tracking in magnetic fields. This method is quite general and is based on the solution of the Hamilton-Jacobi equation. It requires an analytical representation of the fields, which can be differentiated and integrated. For undulators of the APPLE II type, an accurate analytic field model is derived which is suitable for the tracking routine. This field model is fully parametrized representing all operation modes for the production of elliptical or linear polarized light with an arbitrary inclination angle or even arbitrary polarization. Based on this field model, analytic expressions for 2nd order kicks are derived. They are used to estimate the influence of APPLE II undulators on the electron beam dynamic. Furthermore, an analytic model for the description of shims is given. The shims are needed for field and performance optimization. Passive and active shimming concepts for the compensation of linear and nonlinear effects of variably polarizing undulators are discussed.

  20. The Tracking and Analysis Framework (TAF): A tool for the integrated assessment of acid deposition

    SciTech Connect

    Bloyd, C.N.; Henrion, M.; Marnicio, R.J.

    1995-06-01

    A major challenge that has faced policy makers concerned with acid deposition is obtaining an integrated view of the underlying science related to acid deposition. In response to this challenge, the US Department of Energy is sponsoring the development of an integrated Tracking and Analysis Framework (TAF) which links together the key acid deposition components of emissions, air transport, atmospheric deposition, and aquatic effects in a single modeling structure. The goal of TAF is to integrate credible models of the scientific and technical issues into an assessment framework that can directly address key policy issues, and in doing so act as a bridge between science and policy. Key objectives of TAF are to support coordination and communication among scientific researchers; to support communications with policy makers, and to provide rapid response for analyzing newly emerging policy issues; and to provide guidance for prioritizing research programs. This paper briefly describes how TAF was formulated to meet those objectives and the underlying principals which form the basis for its development.

  1. Flight parameters monitoring system for tracking structural integrity of rotary-wing aircraft

    NASA Technical Reports Server (NTRS)

    Mohammadi, Jamshid; Olkiewicz, Craig

    1994-01-01

    Recent developments in advanced monitoring systems used in conjunction with tracking structural integrity of rotary-wing aircraft are explained. The paper describes: (1) an overview of rotary-wing aircraft flight parameters that are critical to the aircraft loading conditions and each parameter's specific requirements in terms of data collection and processing; (2) description of the monitoring system and its functions used in a survey of rotary-wing aircraft; and (3) description of the method of analysis used for the data. The paper presents a newly-developed method in compiling flight data. The method utilizes the maneuver sequence of events in several pre-identified flight conditions to describe various flight parameters at three specific weight ranges.

  2. Long-Term MRI Cell Tracking after Intraventricular Delivery in a Patient with Global Cerebral Ischemia and Prospects for Magnetic Navigation of Stem Cells within the CSF

    PubMed Central

    Janowski, Miroslaw; Walczak, Piotr; Kropiwnicki, Tomasz; Jurkiewicz, Elzbieta; Domanska-Janik, Krystyna; Bulte, Jeff W. M.; Lukomska, Barbara; Roszkowski, Marcin

    2014-01-01

    Background The purpose of the study was to evaluate the long-term clinical tracking of magnetically labeled stem cells after intracerebroventricular transplantation as well as to investigate in vitro feasibility for magnetic guidance of cell therapy within large fluid compartments. Method After approval by our Institutional Review Board, an 18-month-old patient, diagnosed as being in a vegetative state due to global cerebral ischemia, underwent cell transplantation to the frontal horn of the lateral ventricle, with umbilical cord blood-derived stem cells labeled with superparamagnetic iron oxide (SPIO) contrast agent. The patient was followed over 33 months with clinical examinations and MRI. To evaluate the forces governing the distribution of cells within the fluid compartment of the ventricular system in vivo, a gravity-driven sedimentation assay and a magnetic field-driven cell attraction assay were developed in vitro. Results Twenty-four hours post-transplantation, MR imaging (MRI) was able to detect hypointense cells in the occipital horn of the lateral ventricle. The signal gradually decreased over 4 months and became undetectable at 33 months. In vitro, no significant difference in cell sedimentation between SPIO-labeled and unlabeled cells was observed (p = NS). An external magnet was effective in attracting cells over distances comparable to the size of human lateral ventricles. Conclusions MR imaging of SPIO-labeled cells allows monitoring of cells within lateral ventricles. While the initial biodistribution is governed by gravity-driven sedimentation, an external magnetic field may possibly be applied to further direct the distribution of labeled cells within large fluid compartments such as the ventricular system. PMID:24919061

  3. Automated real-time instrument tracking for microscope-integrated intraoperative OCT imaging of ophthalmic surgical maneuvers

    NASA Astrophysics Data System (ADS)

    El-Haddad, Mohamed T.; Ehlers, Justis P.; Srivastava, Sunil K.; Tao, Yuankai K.

    2015-03-01

    Optical coherence tomography (OCT) allows high-resolution imaging of tissue microstructure and is the goldstandard for clinical ophthalmic diagnostics. Recent development of microscope-integrated intraoperative OCT (iOCT) systems has allowed cross-sectional imaging of surgical dynamics, but limitations in real-time visualization of instrument-tissue interactions remain the critical barrier for iOCT-guided ophthalmic surgery. Spatial compounding has been previously presented as a method for acquiring, processing, and visualizing cross-sectional iOCT images of surgical maneuvers. However, spatial compounding trades-off temporal resolution and FOV, which generally limits video-rate visualization to small regions at the tip of surgical instruments. To overcome these limitations, we present methods for automated dynamic surgical instrument tracking iOCT. B-scans are obtained along and orthogonal to the instrument axis and centered at the instrument tip at all times to allow cross-sectional visualization of ophthalmic surgical maneuvers for intraoperative guidance. Surgical instrument tracking has been previously demonstrated using different imaging modalities, including an OCT-integrated scanning probe. However, the latter uses large feature points, which are impractical in a surgical setting. Here, we describe automated stereo-vision instrument tracking, which achieves <250 μm accuracy, using tracking feature points that are easily integrated with ophthalmic surgical instruments. The instrument tracking system was integrated with an iOCT system to provide video-rate instrument tip tracked crosssectional B-scan imaging during ophthalmic surgical maneuvers, allowing visualization of tissue-instrument interactions and providing feedback on positioning, depth of penetration, and tissue compression in cadaveric porcine eyes. Real-time instrument tracked cross-sectional imaging can potentially help guide clinical decision-making during ophthalmic surgery.

  4. The Integrated Waste Tracking Systems (IWTS) - A Comprehensive Waste Management Tool

    SciTech Connect

    Robert S. Anderson

    2005-09-01

    The US Department of Energy (DOE) Idaho National Laboratory (INL) site located near Idaho Falls, ID USA, has developed a comprehensive waste management and tracking tool that integrates multiple operational activities with characterization data from waste declaration through final waste disposition. The Integrated Waste Tracking System (IWTS) provides information necessary to help facility personnel properly manage their waste and demonstrate a wide range of legal and regulatory compliance. As a client?server database system, the IWTS is a proven tracking, characterization, compliance, and reporting tool that meets the needs of both operations and management while providing a high level of flexibility. This paper describes some of the history involved with the development and current use of IWTS as a comprehensive waste management tool as well as a discussion of IWTS deployments performed by the INL for outside clients. Waste management spans a wide range of activities including: work group interactions, regulatory compliance management, reporting, procedure management, and similar activities. The IWTS documents these activities and performs tasks in a computer-automated environment. Waste characterization data, container characterization data, shipments, waste processing, disposals, reporting, and limit compliance checks are just a few of the items that IWTS documents and performs to help waste management personnel perform their jobs. Throughout most hazardous and radioactive waste generating, storage and disposal sites, waste management is performed by many different groups of people in many facilities. Several organizations administer their areas of waste management using their own procedures and documentation independent of other organizations. Files are kept, some of which are treated as quality records, others not as stringent. Quality records maintain a history of: changes performed after approval, the reason for the change(s), and a record of whom and when

  5. Labeling the Structural Integrity of Nanoparticles for Advanced In Situ Tracking in Bionanotechnology.

    PubMed

    Meder, Fabian; Thomas, Steffi S; Fitzpatrick, Laurence W; Alahmari, Amirah; Wang, Suxiao; Beirne, Jason G; Vaz, Gizela; Redmond, Gareth; Dawson, Kenneth A

    2016-04-26

    Observing structural integrity of nanoparticles is essential in bionanotechnology but not always straightforward to measure in situ and in real-time. Fluorescent labels used for tracking intrinsically nonfluorescent nanomaterials generally do not allow simultaneous observation of integrity. Consequently, structural changes like degradation and disassembly cannot easily be followed in situ using fluorescence signals. We show that thioflavin T (ThT), a fluorophore and molecular rotor known to tag specific fibril structures in amyloids, can "label" the structural integrity of widely used and intrinsically nonfluorescent, silica nanoparticles (SiNPs). Entrapment of ThT in SiNPs controls the fluorohphore's relaxation pathway and leads to a red-shifted fluorescence spectrum providing real time information on SiNP integrity. The dynamic change of ThT fluorescence during degradation of doped SiNPs is found much higher than that of common labels fluorescein and rhodamine. Degradation kinetics of core-shell structures recorded by ThT fluorescence and light scattering prove the capability to clearly distinguish structural features during SiNPs degradation and allow obtaining degradation kinetics in vitro, in biological media, in serum, and in cells. The effect is transferable to different types of materials, here shown for ThT incorporated SiNPs with tightly tailorable sizes (9-100 nm), poly(lactic-co-glycolic acid) (PLGA) nanoparticles, poly(9-vinylcarbazole) (PVK) nanoparticles, and iron-doped-SiNPs (FeSiNPs). We thus suggest molecular rotors such as ThT as additional labels to effectively and easily sense nanoparticle structural status in situ and to enhance understanding and development of programmed nanoparticle disassembly in bionanotechnology. PMID:26959685

  6. Managing your investment in environmental compliance with integrated cost and benefit tracking analysis

    SciTech Connect

    Easter, C.D.

    1997-12-31

    This paper is designed to assist environmental managers in establishing an integrated approach to tracking the economic cost and benefit of compliance with environmental regulations. The Integrated Environmental Management System (IEMS) consists of a program which outlines reports, permits, data analysis and construction related projects that are necessary for compliance with federal, state and local requirements and establishes a dollar value in terms of both labor hours and capital expenditures for a given facility. This dollar value is cross-referenced with an Environmental Benefit Score (EBS) which is a ``weighted`` function of the following factors: pollution reduction, employee health and safety protection, community/public relations benefits and program/equipment durability. This system will improve the environmental budget managers` ability to efficiently apply resources to the proper project areas for maximum benefit. The data for this paper was compiled by reviewing environmental expenditure data for facilities over the previous decade and analyzing the impact in terms of the heretofore mentioned factors included in the Environmental Benefit Score (EBS). Through this process, a model program was designed which can be applied, with adjustments, to either public or private organizations. It is clear that a well managed and carefully chosen program of resource allocation is more efficient than a blanket program that attempts to broadly comply with all regulatory challenges concurrently.

  7. Cerebral Hypoxia

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS NINDS Cerebral Hypoxia Information Page Synonym(s): Hypoxia, Anoxia Table of Contents ( ... Trials Organizations Publicaciones en Español What is Cerebral Hypoxia? Cerebral hypoxia refers to a condition in which ...

  8. Crystal Structure of CCM3, a Cerebral Cavernous Malformation Protein Critical for Vascular Integrity

    SciTech Connect

    Li, X.; Zhang, R; Zhang, H; He, Y; Ji, W; Min, W; Boggon, T

    2010-01-01

    CCM3 mutations are associated with cerebral cavernous malformation (CCM), a disease affecting 0.1-0.5% of the human population. CCM3 (PDCD10, TFAR15) is thought to form a CCM complex with CCM1 and CCM2; however, the molecular basis for these interactions is not known. We have determined the 2.5 {angstrom} crystal structure of CCM3. This structure shows an all {alpha}-helical protein containing two domains, an N-terminal dimerization domain with a fold not previously observed, and a C-terminal focal adhesion targeting (FAT)-homology domain. We show that CCM3 binds CCM2 via this FAT-homology domain and that mutation of a highly conserved FAK-like hydrophobic pocket (HP1) abrogates CCM3-CCM2 interaction. This CCM3 FAT-homology domain also interacts with paxillin LD motifs using the same surface, and partial CCM3 co-localization with paxillin in cells is lost on HP1 mutation. Disease-related CCM3 truncations affect the FAT-homology domain suggesting a role for the FAT-homology domain in the etiology of CCM.

  9. Crystal Structure of CCM3, a Cerebral Cavernous Malformation Protein Critical for Vascular Integrity*

    PubMed Central

    Li, Xiaofeng; Zhang, Rong; Zhang, Haifeng; He, Yun; Ji, Weidong; Min, Wang; Boggon, Titus J.

    2010-01-01

    CCM3 mutations are associated with cerebral cavernous malformation (CCM), a disease affecting 0.1–0.5% of the human population. CCM3 (PDCD10, TFAR15) is thought to form a CCM complex with CCM1 and CCM2; however, the molecular basis for these interactions is not known. We have determined the 2.5 Å crystal structure of CCM3. This structure shows an all α-helical protein containing two domains, an N-terminal dimerization domain with a fold not previously observed, and a C-terminal focal adhesion targeting (FAT)-homology domain. We show that CCM3 binds CCM2 via this FAT-homology domain and that mutation of a highly conserved FAK-like hydrophobic pocket (HP1) abrogates CCM3-CCM2 interaction. This CCM3 FAT-homology domain also interacts with paxillin LD motifs using the same surface, and partial CCM3 co-localization with paxillin in cells is lost on HP1 mutation. Disease-related CCM3 truncations affect the FAT-homology domain suggesting a role for the FAT-homology domain in the etiology of CCM. PMID:20489202

  10. @neurIST complex information processing toolchain for the integrated management of cerebral aneurysms

    PubMed Central

    Villa-Uriol, M. C.; Berti, G.; Hose, D. R.; Marzo, A.; Chiarini, A.; Penrose, J.; Pozo, J.; Schmidt, J. G.; Singh, P.; Lycett, R.; Larrabide, I.; Frangi, A. F.

    2011-01-01

    Cerebral aneurysms are a multi-factorial disease with severe consequences. A core part of the European project @neurIST was the physical characterization of aneurysms to find candidate risk factors associated with aneurysm rupture. The project investigated measures based on morphological, haemodynamic and aneurysm wall structure analyses for more than 300 cases of ruptured and unruptured aneurysms, extracting descriptors suitable for statistical studies. This paper deals with the unique challenges associated with this task, and the implemented solutions. The consistency of results required by the subsequent statistical analyses, given the heterogeneous image data sources and multiple human operators, was met by a highly automated toolchain combined with training. A testimonial of the successful automation is the positive evaluation of the toolchain by over 260 clinicians during various hands-on workshops. The specification of the analyses required thorough investigations of modelling and processing choices, discussed in a detailed analysis protocol. Finally, an abstract data model governing the management of the simulation-related data provides a framework for data provenance and supports future use of data and toolchain. This is achieved by enabling the easy modification of the modelling approaches and solution details through abstract problem descriptions, removing the need of repetition of manual processing work. PMID:22670202

  11. MetaTracker: integration and abstraction of 3D motion tracking data from multiple hardware systems

    NASA Astrophysics Data System (ADS)

    Kopecky, Ken; Winer, Eliot

    2014-06-01

    Motion tracking has long been one of the primary challenges in mixed reality (MR), augmented reality (AR), and virtual reality (VR). Military and defense training can provide particularly difficult challenges for motion tracking, such as in the case of Military Operations in Urban Terrain (MOUT) and other dismounted, close quarters simulations. These simulations can take place across multiple rooms, with many fast-moving objects that need to be tracked with a high degree of accuracy and low latency. Many tracking technologies exist, such as optical, inertial, ultrasonic, and magnetic. Some tracking systems even combine these technologies to complement each other. However, there are no systems that provide a high-resolution, flexible, wide-area solution that is resistant to occlusion. While frameworks exist that simplify the use of tracking systems and other input devices, none allow data from multiple tracking systems to be combined, as if from a single system. In this paper, we introduce a method for compensating for the weaknesses of individual tracking systems by combining data from multiple sources and presenting it as a single tracking system. Individual tracked objects are identified by name, and their data is provided to simulation applications through a server program. This allows tracked objects to transition seamlessly from the area of one tracking system to another. Furthermore, it abstracts away the individual drivers, APIs, and data formats for each system, providing a simplified API that can be used to receive data from any of the available tracking systems. Finally, when single-piece tracking systems are used, those systems can themselves be tracked, allowing for real-time adjustment of the trackable area. This allows simulation operators to leverage limited resources in more effective ways, improving the quality of training.

  12. Evaluating an Integrated Approach to the Management of Cerebral Palsy. Appendix B: Field Test Report of the Eau Claire Functional Abilities Test and the Wolfe-Bluel Socialization Inventory. Volume III of IV. Final Report.

    ERIC Educational Resources Information Center

    Heal, Laird W.

    The appendix examined the measurement instruments developed in the course of the Integrated Management of Cerebral Palsy project to measure functional movements and socialization skills of severly handicapped, nonambulatory cerebral palsied children who had limited speech. The field test sample consisted of 51 cases for the Eau Claire Functional…

  13. Robust synchronisation tracking control of networked Euler-Lagrange systems using reference trajectory estimation based on virtual double-integrators

    NASA Astrophysics Data System (ADS)

    Yang, Zi-Jiang; Qin, Pan

    2016-07-01

    This paper considers the problem of distributed synchronisation tracking control of multiple Euler-Lagrange systems on a directed graph which contains a spanning tree with the leader node being the root. To design the high performance distributed controllers, a virtual double-integrator is introduced in each agent and is controlled by a virtual distributed linear high-gain synchronisation tracking controller, so that the position and velocity of each agent track those of the reference trajectory with arbitrarily short transient time and small ultimate tracking error. Then taking the double-integrator's position and velocity as the estimates of those of the reference trajectory, in each generalised coordinate of each Euler-Lagrange agent, a local controller with a disturbance observer and a sliding mode control term is designed, to suppress the mutual interactions among the agents and the modelling uncertainties. The boundedness of the overall signals and the synchronisation tracking control performance are analysed, and the conditions for guaranteed control performance are clarified. Simulation examples are provided to demonstrate the performance of the distributed controllers.

  14. Tracking patient radiation exposure: challenges to integrating nuclear medicine with other modalities.

    PubMed

    Mercuri, Mathew; Rehani, Madan M; Einstein, Andrew J

    2012-10-01

    The cumulative radiation exposure to the patient from multiple radiological procedures can place some individuals at significantly increased risk for stochastic effects and tissue reactions. Approaches, such as those in the International Atomic Energy Agency's Smart Card program, have been developed to track cumulative radiation exposures to individuals. These strategies often rely on the availability of structured dose reports, typically found in the DICOM header. Dosimetry information is currently readily available for many individual x-ray-based procedures. Nuclear medicine, of which nuclear cardiology constitutes the majority of the radiation burden in the US, currently lags behind x-ray-based procedures with respect to reporting of radiation dosimetric information. This article discusses qualitative differences between nuclear medicine and x-ray-based procedures, including differences in the radiation source and measurement of its strength, the impact of biokinetics on dosimetry, and the capability of current scanners to record dosimetry information. These differences create challenges in applying, monitoring, and reporting strategies used in x-ray-based procedures to nuclear medicine, and integrating dosimetry information across modalities. A concerted effort by the medical imaging community, dosimetry specialists, and manufacturers of imaging equipment is required to develop strategies to improve the reporting of radiation dosimetry data in nuclear medicine. Some ideas on how to address this issue are suggested. PMID:22695788

  15. On the energy integral formulation of gravitational potential differences from satellite-to-satellite tracking

    NASA Astrophysics Data System (ADS)

    Guo, J. Y.; Shang, K.; Jekeli, C.; Shum, C. K.

    2015-04-01

    Two approaches have been formulated to compute the gravitational potential difference using low-low satellite-to-satellite tracking data based on energy integral: one in the geocentric inertial reference system, and the other in the terrestrial reference system. The focus of this work is on the approach in the geocentric inertial reference system, where a potential rotation term appears in addition to the potential term. In former formulations, the contribution of the time-variable components of the gravitational potential to the potential term was included, but their contribution to the potential rotation term was neglected. In this work, an improvement to the former formulations is made by reformulating the potential rotation term to include the contribution of the time-variable components of the gravitational potential. A simulation shows that our more accurate formulation of the potential rotation term is necessary to achieve the accuracy for recovering the temporal variation of the Earth's gravity field, such as for use to the Gravity Recovery And Climate Experiment GRACE observation data based on this approach.

  16. Tracking of mesenchymal stem cells labeled with gadolinium diethylenetriamine pentaacetic acid by 7T magnetic resonance imaging in a model of cerebral ischemia

    PubMed Central

    GENG, KUAN; YANG, ZHONG XIAN; HUANG, DEXIAO; YI, MEIZI; JIA, YANLONG; YAN, GEN; CHENG, XIAOFANG; WU, RENHUA

    2015-01-01

    Progress in the development of stem cell and gene therapy requires repeatable and non-invasive techniques to monitor the survival and integration of stem cells in vivo with a high temporal and spatial resolution. The purpose of the present study was to examine the feasibility of using the standard contrast agent gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) to label rat mesenchymal stem cells (MSCs) for stem cell tracking. MSCs, obtained from the bilateral femora of rats, were cultured and propagated. The non-liposomal lipid transfection reagent effectene was then used to induce the intracellular uptake of Gd-DTPA. Electron microscopy was used to detect the distribution of Gd-DTPA particles in the MSCs. The labeling efficiency of the Gd-DTPA particles in the MSCs was determined using spectrophotometry, and MTT and trypan blue exclusion assays were used to evaluate the viability and proliferation of the labeled MSCs. T1-weighted magnetic resonance imaging (MRI) was used to observe the labeled cells in vitro and in the rat brain. Gd-DTPA particles were detected inside the MSCs using transmission electron microscopy and a high labeling efficiency was observed. No difference was observed in cell viability or proliferation between the labeled and unlabeled MSCs (P>0.05). In the in vitro T1-weighted MRI and in the rat brain, a high signal intensity was observed in the labeled MSCs. The T1-weighted imaging of the labeled cells revealed a significantly higher signal intensity compared with that of the unlabeled cells (P<0.05) and the T1 values were significantly lower. The function of the labeled MSCs demonstrated no change following Gd-DTPA labeling, with no evident adverse effect on cell viability or proliferation. Therefore, a change in MR signal intensity was detected in vitro and in vivo, suggesting Gd-DTPA can be used to label MSCs for MRI tracking. PMID:25352164

  17. Altered white matter integrity and functional connectivity of hyperacute-stage cerebral ischemia in a rat model.

    PubMed

    Cha, Jihoon; Kim, Sung Tae; Jung, Won Beom; Han, Yong Hee; Im, Geun Ho; Lee, Jung Hee

    2016-10-01

    Ischemic stroke is accompanied by structural deformation and functional deficits in the affected hemisphere. Within a couple of hours after symptom onset, the accurate identification of brain characteristics is critical to design the therapeutic strategies and it can potentially improve overall brain tissue viability by minimizing irreversible brain damage. In this study, white matter integrity and functional connectivity within 2-4h after right middle cerebral artery occlusion in rats were investigated using multimodal magnetic resonance imaging. During this stage, diffusion tensor image (DTI) revealed that fractional anisotropy along the ipsilesional external capsule was slightly increased as compared with preoperative baseline. Resting state functional MRI (rs-fMRI) showed that the inter-hemispheric functional connectivities from primary motor (M1), primary somatosensory of forelimb (S1FL), and barrel field (S1BF) seeds were considerably reduced at the hyperacute stage. Fractional amplitudes of low frequency fluctuations (fALFF) from rs-fMRI were significantly enhanced at the hyperacute stage in the frequency spectrum between 0.01 and 0.08Hz. In addition, the changes in fALFF were negatively correlated with the number of functionally connected voxels in M1, S1FL and S1BF. Our results suggest that these techniques are useful tools to evaluate remarkable brain changes in the hyperacute stage of ischemic stroke. PMID:27108358

  18. Transcranial direct current stimulation combined with integrative speech therapy in a child with cerebral palsy: A case report.

    PubMed

    Carvalho Lima, Vania L C; Collange Grecco, Luanda A; Marques, Valéria C; Fregni, Felipe; Brandão de Ávila, Clara R

    2016-04-01

    The aim of this study was to describe the results of the first case combining integrative speech therapy with anodal transcranial direct current stimulation (tDCS) over Broca's area in a child with cerebral palsy. The ABFW phonology test was used to analyze speech based on the Percentage of Correct Consonants (PCC) and Percentage of Correct Consonants - Revised (PCC-R). After treatment, increases were found in both PCC (Imitation: 53.63%-78.10%; Nomination: 53.19%-70.21%) and PPC-R (Imitation: 64.54%-83.63%; Nomination: 61.70%-77.65%). Moreover, reductions occurred in distortions, substitutions and improvement was found in oral performance, especially tongue mobility (AMIOFE-mobility before = 4 after = 7). The child demonstrated a clinically important improvement in speech fluency as shown in results of imitation number of correct consonants and phonemes acquire. Based on these promising findings, continuing research in this field should be conducted with controlled clinical trials. PMID:27210840

  19. Integrated Analysis of Expression Profile Based on Differentially Expressed Genes in Middle Cerebral Artery Occlusion Animal Models.

    PubMed

    Zhou, Huaqiang; Qiu, Zeting; Gao, Shaowei; Chen, Qinchang; Li, Si; Tan, Wulin; Liu, Xiaochen; Wang, Zhongxing

    2016-01-01

    Stroke is one of the most common causes of death, only second to heart disease. Molecular investigations about stroke are in acute shortage nowadays. This study is intended to explore a gene expression profile after brain ischemia reperfusion. Meta-analysis, differential expression analysis, and integrated analysis were employed on an eight microarray series. We explored the functions and pathways of target genes in gene ontology (GO) enrichment analysis and constructed a protein-protein interaction network. Meta-analysis identified 360 differentially expressed genes (DEGs) for Mus musculus and 255 for Rattus norvegicus. Differential expression analysis identified 44 DEGs for Mus musculus and 21 for Rattus norvegicus. Timp1 and Lcn2 were overexpressed in both species. The cytokine-cytokine receptor interaction and chemokine signaling pathway were highly enriched for the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. We have exhibited a global view of the potential molecular differences between middle cerebral artery occlusion (MCAO) animal model and sham for Mus musculus or Rattus norvegicus, including the biological process and enriched pathways in DEGs. This research helps contribute to a clearer understanding of the inflammation process and accurate identification of ischemic infarction stages, which might be transformed into a therapeutic approach. PMID:27213359

  20. Integrated Analysis of Expression Profile Based on Differentially Expressed Genes in Middle Cerebral Artery Occlusion Animal Models

    PubMed Central

    Zhou, Huaqiang; Qiu, Zeting; Gao, Shaowei; Chen, Qinchang; Li, Si; Tan, Wulin; Liu, Xiaochen; Wang, Zhongxing

    2016-01-01

    Stroke is one of the most common causes of death, only second to heart disease. Molecular investigations about stroke are in acute shortage nowadays. This study is intended to explore a gene expression profile after brain ischemia reperfusion. Meta-analysis, differential expression analysis, and integrated analysis were employed on an eight microarray series. We explored the functions and pathways of target genes in gene ontology (GO) enrichment analysis and constructed a protein-protein interaction network. Meta-analysis identified 360 differentially expressed genes (DEGs) for Mus musculus and 255 for Rattus norvegicus. Differential expression analysis identified 44 DEGs for Mus musculus and 21 for Rattus norvegicus. Timp1 and Lcn2 were overexpressed in both species. The cytokine-cytokine receptor interaction and chemokine signaling pathway were highly enriched for the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. We have exhibited a global view of the potential molecular differences between middle cerebral artery occlusion (MCAO) animal model and sham for Mus musculus or Rattus norvegicus, including the biological process and enriched pathways in DEGs. This research helps contribute to a clearer understanding of the inflammation process and accurate identification of ischemic infarction stages, which might be transformed into a therapeutic approach. PMID:27213359

  1. Novel human-robot interface integrating real-time visual tracking and microphone-array signal processing

    NASA Astrophysics Data System (ADS)

    Mizoguchi, Hiroshi; Shigehara, Takaomi; Goto, Yoshiyasu; Hidai, Ken-ichi; Mishima, Taketoshi

    1998-10-01

    This paper proposes a novel human robot interface that is an integration of real time visual tracking and microphone array signal processing. The proposed interface is intended to be used as a speech signal input method for human collaborative robot. Utilizing it, the robot can clearly listen human master's voice remotely as if a wireless microphone were put just in front of the master. A novel technique to form `acoustic focus' at human face is developed. To track and locate the face dynamically, real time face tracking and stereo vision are utilized. To make the acoustic focus at the face, microphones array is utilized. Setting gain and delay of each microphone properly enables to form acoustic focus at desired location. The gain and delay are determined based upon the location of the face. Results of preliminary experiments and simulations demonstrate feasibility of the proposed idea.

  2. Age-related slowing of memory retrieval: Contributions of perceptual speed and cerebral white matter integrity

    PubMed Central

    Bucur, Barbara; Madden, David J.; Spaniol, Julia; Provenzale, James M.; Cabeza, Roberto; White, Leonard E.; Huettel, Scott A.

    2007-01-01

    Previous research suggests that, in reaction time (RT) measures of episodic memory retrieval, the unique effects of adult age are relatively small compared to the effects aging shares with more elementary abilities such as perceptual speed. Little is known, however, regarding the mechanisms of perceptual speed. We used diffusion tensor imaging (DTI) to test the hypothesis that white matter integrity, as indexed by fractional anisotropy (FA), serves as one mechanism of perceptual slowing in episodic memory retrieval. Results indicated that declines in FA in the pericallosal frontal region and in the genu of the corpus callosum, but not in other regions, mediated the relationship between perceptual speed and episodic retrieval RT. This relation held, though to a different degree, for both hits and correct rejections. These findings suggest that white matter integrity in prefrontal regions is one mechanism underlying the relation between individual differences in perceptual speed and episodic retrieval. PMID:17383774

  3. Evidence-based use of electronic clinical tracking systems in advanced practice registered nurse education: an integrative review.

    PubMed

    Branstetter, M Laurie; Smith, Lynette S; Brooks, Andrea F

    2014-07-01

    Over the past decade, the federal government has mandated healthcare providers to incorporate electronic health records into practice by 2015. This technological update in healthcare documentation has generated a need for advanced practice RN programs to incorporate information technology into education. The National Organization of Nurse Practitioner Faculties created core competencies to guide program standards for advanced practice RN education. One core competency is Technology and Information Literacy. Educational programs are moving toward the utilization of electronic clinical tracking systems to capture students' clinical encounter data. The purpose of this integrative review was to evaluate current research on advanced practice RN students' documentation of clinical encounters utilizing electronic clinical tracking systems to meet advanced practice RN curriculum outcome goals in information technology as defined by the National Organization of Nurse Practitioner Faculties. The state of the science depicts student' and faculty attitudes, preferences, opinions, and data collections of students' clinical encounters. Although electronic clinical tracking systems were utilized to track students' clinical encounters, these systems have not been evaluated for meeting information technology core competency standards. Educational programs are utilizing electronic clinical tracking systems with limited evidence-based literature evaluating the ability of these systems to meet the core competencies in advanced practice RN programs. PMID:24814999

  4. Integration of the real-time tracking gradiometer (RTG) aboard the autonomous underwater vehicle (AUV) Morpheus

    NASA Astrophysics Data System (ADS)

    Allen, George I.; Matthews, Robert; Wynn, Michael

    2001-10-01

    In keeping with the Navy's policy to remove humans from harms way, the Autonomous Underwater Vehicle (AUV) is replacing human divers for many missions. The Advanced Marine Systems Lab at Florida Atlantic University (FAU) has developed a small, magnetically friendly, modular plastic AUV called Morpheus designed for coastal applications and especially suited for very shallow water (VSW) mine reconnaissance. Currently employed sensor technologies on AUVs have certain deficiencies and limitations when used across the wide gamut of naval targets and environments, and a strong requirement exists for a sensor or sensors to fill these niches. The Real-time Tracking Gradiometer (RTG) selected for this integration is truly such a niche sensor because its capabilities are not degraded by media interfaces or environmental conditions. It is an experimental prototype fluxgate magnetometer array developed by Quantum Magnetics for the Coastal Systems Station (CSS) and was designed to be man portable and self contained. While limited by physics in detection range, it is capable of detecting ferrous targets under the worst environmental conditions, even when the target is buried. While not having the range of sonar, the RTG does not respond to the false alarms that are indicated by sonar, and since it is capable of also providing range and bearing information, it provides an invaluable niche filling classification tool. The placing of any magnetic sensing system on a conventional AUV is a non-trivial problem. The standard AUV is designed around materials and components that were selected to maximize performance without regard to the magnetic properties of the materials used in its fabrication. To minimize the degradation of sensor performance caused by the platform, several steps must be taken. These include; the substitution of nonferrous components for ferrous, maximizing the separation between the sensor and magnetic field sources, minimizing current loops and using auxiliary

  5. Lateral charge transport from heavy-ion tracks in integrated circuit chips

    NASA Technical Reports Server (NTRS)

    Zoutendyk, J. A.; Schwartz, H. R.; Nevill, L. R.

    1988-01-01

    A 256K DRAM has been used to study the lateral transport of charge (electron-hole pairs) induced by direct ionization from heavy-ion tracks in an IC. The qualitative charge transport has been simulated using a two-dimensional numerical code in cylindrical coordinates. The experimental bit-map data clearly show the manifestation of lateral charge transport in the creation of adjacent multiple-bit errors from a single heavy-ion track. The heavy-ion data further demonstrate the occurrence of multiple-bit errors from single ion tracks with sufficient stopping power. The qualitative numerical simulation results suggest that electric-field-funnel-aided (drift) collection accounts for single error generated by an ion passing through a charge-collecting junction, while multiple errors from a single ion track are due to lateral diffusion of ion-generated charge.

  6. Cerebral Palsy

    MedlinePlus

    ... Got Homework? Here's Help White House Lunch Recipes Cerebral Palsy KidsHealth > For Kids > Cerebral Palsy Print A A ... the things that kids do every day. What's CP? Some kids with CP use wheelchairs and others ...

  7. Cerebral Palsy

    MedlinePlus

    ... Loss > Birth defects & other health conditions > Cerebral palsy Cerebral palsy E-mail to a friend Please fill in ... movement problems a child has. What is spastic CP? Spastic means tight or stiff muscles, or muscles ...

  8. Cerebral Palsy

    MedlinePlus

    Cerebral palsy is a group of disorders that affect a person's ability to move and to maintain balance ... do not get worse over time. People with cerebral palsy may have difficulty walking. They may also have ...

  9. Cerebral palsy

    MedlinePlus

    Cerebral palsy is a group of disorders that can involve brain and nervous system functions, such as movement, ... and thinking. There are several different types of cerebral palsy, including spastic, dyskinetic, ataxic, hypotonic, and mixed.

  10. Cerebral Palsy

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Cerebral Palsy Information Page Clinical Trials Trial of Erythropoietin Neuroprotection ... en Español Additional resources from MedlinePlus What is Cerebral Palsy? The term cerebral palsy refers to a group ...

  11. Cerebral Aneurysms

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS NINDS Cerebral Aneurysms Information Page Synonym(s): Aneurysm, Brain Aneurysm Condensed from ... Español Additional resources from MedlinePlus What is Cerebral Aneurysms? A cerebral aneurysm is a weak or thin ...

  12. A radar-enabled collaborative sensor network integrating COTS technology for surveillance and tracking.

    PubMed

    Kozma, Robert; Wang, Lan; Iftekharuddin, Khan; McCracken, Ernest; Khan, Muhammad; Islam, Khandakar; Bhurtel, Sushil R; Demirer, R Murat

    2012-01-01

    The feasibility of using Commercial Off-The-Shelf (COTS) sensor nodes is studied in a distributed network, aiming at dynamic surveillance and tracking of ground targets. Data acquisition by low-cost (<$50 US) miniature low-power radar through a wireless mote is described. We demonstrate the detection, ranging and velocity estimation, classification and tracking capabilities of the mini-radar, and compare results to simulations and manual measurements. Furthermore, we supplement the radar output with other sensor modalities, such as acoustic and vibration sensors. This method provides innovative solutions for detecting, identifying, and tracking vehicles and dismounts over a wide area in noisy conditions. This study presents a step towards distributed intelligent decision support and demonstrates effectiveness of small cheap sensors, which can complement advanced technologies in certain real-life scenarios. PMID:22438713

  13. A Radar-Enabled Collaborative Sensor Network Integrating COTS Technology for Surveillance and Tracking

    PubMed Central

    Kozma, Robert; Wang, Lan; Iftekharuddin, Khan; McCracken, Ernest; Khan, Muhammad; Islam, Khandakar; Bhurtel, Sushil R.; Demirer, R. Murat

    2012-01-01

    The feasibility of using Commercial Off-The-Shelf (COTS) sensor nodes is studied in a distributed network, aiming at dynamic surveillance and tracking of ground targets. Data acquisition by low-cost (<$50 US) miniature low-power radar through a wireless mote is described. We demonstrate the detection, ranging and velocity estimation, classification and tracking capabilities of the mini-radar, and compare results to simulations and manual measurements. Furthermore, we supplement the radar output with other sensor modalities, such as acoustic and vibration sensors. This method provides innovative solutions for detecting, identifying, and tracking vehicles and dismounts over a wide area in noisy conditions. This study presents a step towards distributed intelligent decision support and demonstrates effectiveness of small cheap sensors, which can complement advanced technologies in certain real-life scenarios. PMID:22438713

  14. Adaptive sliding mode dynamic controller with integrator in the loop for nonholonomic wheeled mobile robot trajectory tracking

    NASA Astrophysics Data System (ADS)

    Asif, Muhammad; Junaid Khan, Muhammad; Cai, Ning

    2014-05-01

    In this paper, novel adaptive sliding mode dynamic controller with integrator in the loop is proposed for nonholonomic wheeled mobile robot (WMR). The modified kinematics controller is used to generate kinematics velocities of WMR which are subsequently used as the input to adaptive dynamic controller. Actuator dynamics are also derived to generate actuator voltage of WMR through torque and velocity vectors. Stability of both kinematics and dynamic controller is presented using Lyapunov stability analysis. The proposed scheme is verified and validated using computer simulations for tracking the desired trajectory of WMR. The performance of proposed scheme is compared with standard backstepping kinematics controller and classical sliding mode control. In addition, the performance is further compared with standard backstepping kinematics controller with adaptive sliding mode controller without integrator. It is shown that the proposed scheme exhibits zero steady state error, fast error convergence and robustness in the presence of continuous disturbances and uncertainties.

  15. Electromagnetic Real-Time Tumor Position Monitoring and Dynamic Multileaf Collimator Tracking Using a Siemens 160 MLC: Geometric and Dosimetric Accuracy of an Integrated System

    SciTech Connect

    Krauss, Andreas; Nill, Simeon; Tacke, Martin; Oelfke, Uwe

    2011-02-01

    Purpose: Dynamic multileaf collimator tracking represents a promising method for high-precision radiotherapy to moving tumors. In the present study, we report on the integration of electromagnetic real-time tumor position monitoring into a multileaf collimator-based tracking system. Methods and Materials: The integrated system was characterized in terms of its geometric and radiologic accuracy. The former was assessed from portal images acquired during radiation delivery to a phantom in tracking mode. The tracking errors were calculated from the positions of the tracking field and of the phantom as extracted from the portal images. Radiologic accuracy was evaluated from film dosimetry performed for conformal and intensity-modulated radiotherapy applied to different phantoms moving on sinusoidal trajectories. A static radiation delivery to the nonmoving target served as a reference for the delivery to the moving phantom with and without tracking applied. Results: Submillimeter tracking accuracy was observed for two-dimensional target motion despite the relatively large system latency of 500 ms. Film dosimetry yielded almost complete recovery of a circular dose distribution with tracking in two dimensions applied: 2%/2 mm gamma-failure rates could be reduced from 59.7% to 3.3%. For single-beam intensity-modulated radiotherapy delivery, accuracy was limited by the finite leaf width. A 2%/2 mm gamma-failure rate of 15.6% remained with tracking applied. Conclusion: The integrated system we have presented marks a major step toward the clinical implementation of high-precision dynamic multileaf collimator tracking. However, several challenges such as irregular motion traces or a thorough quality assurance still need to be addressed.

  16. Real-time correction by optical tracking with integrated geometric distortion correction for reducing motion artifacts in functional MRI.

    PubMed

    Rotenberg, David; Chiew, Mark; Ranieri, Shawn; Tam, Fred; Chopra, Rajiv; Graham, Simon J

    2013-03-01

    Head motion artifacts are a major problem in functional MRI that limit its use in neuroscience research and clinical settings. Real-time scan-plane correction by optical tracking has been shown to correct slice misalignment and nonlinear spin-history artifacts; however, residual artifacts due to dynamic magnetic field nonuniformity may remain in the data. A recently developed correction technique, Phase Labeling for Additional Coordinate Encoding, can correct for absolute geometric distortion using only the complex image data from two echo planar images with slightly shifted k-space trajectories. An approach is presented that integrates Phase Labeling for Additional Coordinate Encoding into a real-time scan-plane update system by optical tracking, applied to a tissue-equivalent phantom undergoing complex motion and an functional MRI finger tapping experiment with overt head motion to induce dynamic field nonuniformity. Experiments suggest that such integrated volume-by-volume corrections are very effective at artifact suppression, with potential to expand functional MRI applications. PMID:22585554

  17. JLAB Web Based Tracking System for Integrated Incident, Accident, Inspection, and Assessments

    SciTech Connect

    S. Prior; R. Lawrence

    2003-09-01

    The Thomas Jefferson National Accelerator Facility, or JLab, is a Department of Energy particle accelerator used to conduct fundamental physics research. In such a facility there are numerous statutory, regulatory, contractual, and best practice requirements for managing and analyzing environmental health and safety (EH&S) related data. A tracking system has been developed at JLab that meets the needs of all levels of the organization, from the front line worker to the most senior management. This paper describes the system implementation and performance to date.

  18. Integrated navigation fusion strategy of INS/UWB for indoor carrier attitude angle and position synchronous tracking.

    PubMed

    Fan, Qigao; Wu, Yaheng; Hui, Jing; Wu, Lei; Yu, Zhenzhong; Zhou, Lijuan

    2014-01-01

    In some GPS failure conditions, positioning for mobile target is difficult. This paper proposed a new method based on INS/UWB for attitude angle and position synchronous tracking of indoor carrier. Firstly, error model of INS/UWB integrated system is built, including error equation of INS and UWB. And combined filtering model of INS/UWB is researched. Simulation results show that the two subsystems are complementary. Secondly, integrated navigation data fusion strategy of INS/UWB based on Kalman filtering theory is proposed. Simulation results show that FAKF method is better than the conventional Kalman filtering. Finally, an indoor experiment platform is established to verify the integrated navigation theory of INS/UWB, which is geared to the needs of coal mine working environment. Static and dynamic positioning results show that the INS/UWB integrated navigation system is stable and real-time, positioning precision meets the requirements of working condition and is better than any independent subsystem. PMID:25121111

  19. Integrated Navigation Fusion Strategy of INS/UWB for Indoor Carrier Attitude Angle and Position Synchronous Tracking

    PubMed Central

    Wu, Yaheng; Hui, Jing; Wu, Lei; Zhou, Lijuan

    2014-01-01

    In some GPS failure conditions, positioning for mobile target is difficult. This paper proposed a new method based on INS/UWB for attitude angle and position synchronous tracking of indoor carrier. Firstly, error model of INS/UWB integrated system is built, including error equation of INS and UWB. And combined filtering model of INS/UWB is researched. Simulation results show that the two subsystems are complementary. Secondly, integrated navigation data fusion strategy of INS/UWB based on Kalman filtering theory is proposed. Simulation results show that FAKF method is better than the conventional Kalman filtering. Finally, an indoor experiment platform is established to verify the integrated navigation theory of INS/UWB, which is geared to the needs of coal mine working environment. Static and dynamic positioning results show that the INS/UWB integrated navigation system is stable and real-time, positioning precision meets the requirements of working condition and is better than any independent subsystem. PMID:25121111

  20. Variance of time-of-flight distribution is sensitive to cerebral blood flow as demonstrated by ICG bolus-tracking measurements in adult pigs

    PubMed Central

    Elliott, Jonathan T.; Milej, Daniel; Gerega, Anna; Weigl, Wojciech; Diop, Mamadou; Morrison, Laura B.; Lee, Ting-Yim; Liebert, Adam; St. Lawrence, Keith

    2013-01-01

    Variance of time-of-flight distributions have been shown to be more sensitive to cerebral blood flow (CBF) during dynamic-contrast enhanced monitoring of neurotrauma patients than attenuation. What is unknown is the degree to which variance is affected by changes in extracerebral blood flow. Furthermore, the importance of acquiring the arterial input function (AIF) on quantitative analysis of the data is not yet clear. This animal study confirms that variance is both sensitive and specific to changes occurring in the brain when measurements are acquired on the surface of the scalp. Furthermore, when the variance data along with the measured AIF is analyzed using a nonparametric deconvolution method, the recovered change in CBF is in good agreement with CT perfusion values. PMID:23413183

  1. Modeling increased riverine nitrogen export: Source tracking and integrated watershed-coast management.

    PubMed

    Yu, Dan; Yan, Weijin; Chen, Nengwang; Peng, Benrong; Hong, Huasheng; Zhuo, Guihua

    2015-12-30

    The global NEWS model was calibrated and then used to quantify the long term trend of dissolved inorganic nitrogen (DIN) export from two tributaries of Jiulong River (SE China). Anthropogenic N inputs contributed 61-92% of river DIN yield which increased from 337 in 1980s to 1662 kg N km(-2) yr(-1) in 2000s for the North River, and from 653 to 3097 kg N km(-2) yr(-1) for the West River. North River and West River contributed 55% and 45% respectively of DIN loading to the estuary. Rapid development and poor management driven by national policies were responsible for increasing riverine N export. Scenario analysis and source tracking suggest that reductions of anthropogenic N inputs of at least 30% in the North River (emphasis on fertilizer and manure) and 50% in the West River (emphasis on fertilizer) could significantly improve water quality and mitigate eutrophication in both river and coastal waters. PMID:26517942

  2. An integrated modular power-aware microsensor architecture and application to unattended acoustic vehicle tracking

    NASA Astrophysics Data System (ADS)

    Bajura, Michael; Schott, Brian; Flidr, Jaroslav; Czarnaski, Joe; Worth, Carl; Tho, Tam; Wang, Li

    2005-05-01

    We introduce a truly modular, power-aware, distributed microsensor architecture, capable of seamlessly spanning performance metrics from point-optimized low-power to point-optimized high-power applications. This type of performance is often needed in unattended ground sensor applications such as acoustic sensing and tracking, where long periods of minimal sensing activity are intermixed with short periods of intense sensor processing. The system design and implementation of a microsensor platform based on this architecture are described with experimental results. We show that although building a modular power-aware system requires additional hardware components, it results in system capable of rapid physical hardware and software reconfiguration with module reuse for new applications, while achieving a significant decrease in overall system power.

  3. Solar concentrator with integrated tracking and light delivery system with summation

    DOEpatents

    Maxey, Lonnie Curt

    2015-05-05

    A solar light distribution system includes a solar light concentrator that is affixed externally to a light transfer tube. Solar light waves are processed by the concentrator into a collimated beam of light, which is then transferred through a light receiving port and into the light transfer tube. A reflector redirects the collimated beam of light through the tube to a light distribution port. The interior surface of the light transfer tube is highly reflective so that the light transfers through the tube with minimal losses. An interchangeable luminaire is attached to the light distribution port and provides light inside of a structure. A sun tracking device rotates the concentrator and the light transfer tube to optimize the receiving of solar light by the concentrator throughout the day. The system provides interior lighting that uses only renewable energy sources, and releases no carbon dioxide emissions into the atmosphere.

  4. Solar concentrator with integrated tracking and light delivery system with collimation

    DOEpatents

    Maxey, Lonnie Curt

    2015-06-09

    A solar light distribution system includes a solar light concentrator that is affixed externally to a light transfer tube. Solar light waves are processed by the concentrator into a collimated beam of light, which is then transferred through a light receiving port and into the light transfer tube. A reflector directs the collimated beam of light through the tube to a light distribution port. The interior surface of the light transfer tube is highly reflective so that the light transfers through the tube with minimal losses. An interchangeable luminaire is attached to the light distribution port and distributes light inside of a structure. A sun tracking device rotates the concentrator and the light transfer tube to optimize the receiving of solar light by the concentrator throughout the day. The system provides interior lighting, uses only renewable energy sources, and releases no carbon dioxide emissions into the atmosphere.

  5. Angular tolerance and daily performance variability of the Suncycle tracking-integrated CPV system

    NASA Astrophysics Data System (ADS)

    Voarino, Philippe; Domínguez, César; Bijl, Roy; Penning, Peter

    2015-09-01

    The SunCycle CPV system [1] uses two rotating optical stages in order to avoid the need of external sun-tracking while producing a geometrical concentration ratio of 870X. In the European FP7 project CPV4ALL dedicated to demonstrate commercially this system, CEA has developed a complete ray-tracing modeling and has carried out module indoor measurements. The system optical performance was simulated through a spring equinox in Marseille (France). The angular transmission is estimated and evaluated at 0.9°. Furthermore, angular tolerance to chassis misalignments and mirror and prism rotation angles are investigated. The Peak to Average Ratio of the irradiance map of the top and middle sub-cells is estimated for the photogenerated current, which is a value acceptable for such CPV system.

  6. Cerebral palsy.

    PubMed

    Wimalasundera, Neil; Stevenson, Valerie L

    2016-06-01

    Cerebral palsy has always been known as a disorder of movement and posture resulting from a non-progressive injury to the developing brain; however, more recent definitions allow clinicians to appreciate more than just the movement disorder. Accurate classification of cerebral palsy into distribution, motor type and functional level has advanced research. It also facilitates appropriate targeting of interventions to functional level and more accurate prognosis prediction. The prevalence of cerebral palsy remains fairly static at 2-3 per 1000 live births but there have been some changes in trends for specific causal groups. Interventions for cerebral palsy have historically been medical and physically focused, often with limited evidence to support their efficacy. The use of more appropriate outcome measures encompassing quality of life and participation is helping to deliver treatments which are more meaningful for people with cerebral palsy and their carers. PMID:26837375

  7. Tracking the time course of phonetic cue integration during spoken word recognition.

    PubMed

    McMurray, Bob; Clayards, Meghan A; Tanenhaus, Michael K; Aslin, Richard N

    2008-12-01

    Speech perception requires listeners to integrate multiple cues that each contribute to judgments about a phonetic category. Classic studies of trading relations assessed the weights attached to each cue but did not explore the time course of cue integration. Here, we provide the first direct evidence that asynchronous cues to voicing (/b/ vs. /p/) and manner (/b/ vs. /w/) contrasts become available to the listener at different times during spoken word recognition. Using the visual world paradigm, we show that the probability of eye movements to pictures of target and of competitor objects diverge at different points in time after the onset of the target word. These points of divergence correspond to the availability of early (voice onset time or formant transition slope) and late (vowel length) cues to voicing and manner contrasts. These results support a model of cue integration in which phonetic cues are used for lexical access as soon as they are available. PMID:19001568

  8. Soft-error generation due to heavy-ion tracks in bipolar integrated circuits

    NASA Technical Reports Server (NTRS)

    Zoutendyk, J. A.

    1984-01-01

    Both bipolar and MOS integrated circuits have been empirically demonstrated to be susceptible to single-particle soft-error generation, commonly referred to as single-event upset (SEU), which is manifested in a bit-flip in a latch-circuit construction. Here, the intrinsic characteristics of SEU in bipolar (static) RAM's are demonstrated through results obtained from the modeling of this effect using computer circuit-simulation techniques. It is shown that as the dimensions of the devices decrease, the critical charge required to cause SEU decreases in proportion to the device cross-section. The overall results of the simulations are applicable to most integrated circuit designs.

  9. Development and Integration of Genome-Enabled Techniques to Track and Predict the Cycling of Carbon in Model Microbial Communities

    SciTech Connect

    Banfield, Jillian

    2014-11-26

    The primary objective of this project was to establish widely applicable, high-throughput “omics” methods for tracking carbon flow in microbial communities at a strain-resolved molecular level. We developed and applied these methods to study a well-established microbial community model system with a long history of “omics” innovation: chemoautotrophic biofilms grown in an acid mine drainage (AMD) environment. The methods are now being transitioned (in a new project) to study soil. Using metagenomics, stable-isotope proteomics, stable-isotope metabolomics, transcriptomics, and microscopy, we tracked carbon flow during initial biofilm growth involving CO2 fixation, through the maturing biofilm community consisting of multiple trophic levels, and during an anaerobic degradative phase after biofilms sink. This work included explicit consideration of the often overlooked roles of archaea and microbial eukaryotes (fungi) in carbon turnover. We also analyzed where the eosystem begins to fail in response to thermal perturbation, and how perturbation propagates through a carbon cycle. We investigated the form of strain variation in microbial communities, the importance of strain variants, and the rate and form of strain evolution. Overall, the project generated an array of new, integrated ‘omics’ approaches and provided unprecedented insight into the functioning of a natural ecosystem. This project supported graduate training for five Ph.D. students and three post doctoral fellows and contributed directly to at least 26 publications (two in Science).

  10. Myofascial Structural Integration Therapy on Gross Motor Function and Gait of Young Children with Spastic Cerebral Palsy: A Randomized Controlled Trial

    PubMed Central

    Loi, Elizabeth C.; Buysse, Christina A.; Price, Karen S.; Jaramillo, Theresa M.; Pico, Elaine L.; Hansen, Alexis B.; Feldman, Heidi M.

    2015-01-01

    Though the cause of motor abnormalities in cerebral palsy is injury to the brain, structural changes in muscle and fascia may add to stiffness and reduced function. This study examined whether myofascial structural integration therapy, a complementary treatment that manipulates muscle and fascia, would improve gross motor function and gait in children <4 years with cerebral palsy. Participants (N = 29) were enrolled in a randomized controlled trial (NCT01815814, https://goo.gl/TGxvwd) or Open Label Extension. The main outcome was the Gross Motor Function Measure-66 assessed at 3-month intervals. Gait (n = 8) was assessed using the GAITRite® electronic walkway. Parents completed a survey at study conclusion. Comparing Treatment (n = 15) and Waitlist-Control groups (n = 9), we found a significant main effect of time but no effect of group or time × group interaction. The pooled sample (n = 27) showed a main effect of time, but no significantly greater change after treatment than between other assessments. Foot length on the affected side increased significantly after treatment, likely indicating improvement in the children’s ability to approach a heel strike. Parent surveys indicated satisfaction and improvements in the children’s quality of movement. MSI did not increase the rate of motor skill development, but was associated with improvement in gait quality. PMID:26442234

  11. Improved efficiency in clinical workflow of reporting measured oncology lesions via PACS-integrated lesion tracking tool.

    PubMed

    Sevenster, Merlijn; Travis, Adam R; Ganesh, Rajiv K; Liu, Peng; Kose, Ursula; Peters, Joost; Chang, Paul J

    2015-03-01

    OBJECTIVE. Imaging provides evidence for the response to oncology treatment by the serial measurement of reference lesions. Unfortunately, the identification, comparison, measurement, and documentation of several reference lesions can be an inefficient process. We tested the hypothesis that optimized workflow orchestration and tight integration of a lesion tracking tool into the PACS and speech recognition system can result in improvements in oncologic lesion measurement efficiency. SUBJECTS AND METHODS. A lesion management tool tightly integrated into the PACS workflow was developed. We evaluated the effect of the use of the tool on measurement reporting time by means of a prospective time-motion study on 86 body CT examinations with 241 measureable oncologic lesions with four radiologists. RESULTS. Aggregated measurement reporting time per lesion was 11.64 seconds in standard workflow, 16.67 seconds if readers had to register measurements de novo, and 6.36 seconds for each subsequent follow-up study. Differences were statistically significant (p < 0.05) for each reader, except for one difference for one reader. CONCLUSION. Measurement reporting time can be reduced by using a PACS workflow-integrated lesion management tool, especially for patients with multiple follow-up examinations, reversing the onetime efficiency penalty at baseline registration. PMID:25714288

  12. Standard high-reliability integrated circuit logic packaging. [for deep space tracking stations

    NASA Technical Reports Server (NTRS)

    Slaughter, D. W.

    1977-01-01

    A family of standard, high-reliability hardware used for packaging digital integrated circuits is described. The design transition from early prototypes to production hardware is covered and future plans are discussed. Interconnections techniques are described as well as connectors and related hardware available at both the microcircuit packaging and main-frame level. General applications information is also provided.

  13. GeoMedStat: an integrated spatial surveillance system to track air pollution and associated healthcare events.

    PubMed

    Faruque, Fazlay S; Li, Hui; Williams, Worth B; Waller, Lance A; Brackin, Bruce T; Zhang, Lei; Grimes, Kim A; Finley, Richard W

    2014-01-01

    Air pollutants, such as particulate matter with a diameter ≤2.5 microns (PM2.5) and ozone (O3), are known to exacerbate asthma and other respiratory diseases. An integrated surveillance system that tracks such air pollutants and associated disease incidence can assist in risk assessment, healthcare preparedness and public awareness. However, the implementation of such an integrated environmental health surveillance system is a challenge due to the disparate sources of many types of data and the implementation becomes even more complicated for a spatial and real-time system due to lack of standardised technological components and data incompatibility. In addition, accessing and utilising health data that are considered as Protected Health Information (PHI) require maintaining stringent protocols, which have to be supported by the system. This paper aims to illustrate the development of a spatial surveillance system (GeoMedStat) that is capable of tracking daily environmental pollutants along with both daily and historical patient encounter data. It utilises satellite data and the groundmonitor data from the US National Aeronautics and Space Administration (NASA) and the US Environemental Protection Agenecy (EPA), rspectively as inputs estimating air pollutants and is linked to hospital information systems for accessing chief complaints and disease classification codes. The components, developmental methods, functionality of GeoMedStat and its use as a real-time environmental health surveillance system for asthma and other respiratory syndromes in connection with with PM2.5 and ozone are described. It is expected that the framework presented will serve as an example to others developing real-time spatial surveillance systems for pollutants and hospital visits. PMID:25599635

  14. Intrasurgical Human Retinal Imaging With Manual Instrument Tracking Using a Microscope-Integrated Spectral-Domain Optical Coherence Tomography Device

    PubMed Central

    Hahn, Paul; Carrasco-Zevallos, Oscar; Cunefare, David; Migacz, Justin; Farsiu, Sina; Izatt, Joseph A.; Toth, Cynthia A.

    2015-01-01

    Purpose: To characterize the first in-human intraoperative imaging using a custom prototype spectral-domain microscope-integrated optical coherence tomography (MIOCT) device during vitreoretinal surgery with instruments in the eye. Methods: Under institutional review board approval for a prospective intraoperative study, MIOCT images were obtained at surgical pauses with instruments held static in the vitreous cavity and then concurrently with surgical maneuvers. Postoperatively, MIOCT images obtained at surgical pauses were compared with images obtained with a high-resolution handheld spectral-domain OCT (HHOCT) system with objective endpoints, including acquisition of images acceptable for analysis and identification of predefined macular morphologic or pathologic features. Results: Human MIOCT images were successfully obtained before incision and during pauses in surgical maneuvers. MIOCT imaging confirmed preoperative diagnoses, such as epiretinal membrane, full-thickness macular hole, and vitreomacular traction and demonstrated successful achievement of surgical goals. MIOCT and HHOCT images obtained at surgical pauses in two cohorts of five patients were comparable with greater than or equal to 80% correlation in 80% of patients. Real-time video-imaging concurrent with surgical manipulations enabled, for the first time using this device, visualization of dynamic instrument-retina interaction with targeted OCT tracking. Conclusion: MIOCT is successful for imaging at surgical pauses and for real-time image guidance with implementation of targeted OCT tracking. Even faster acquisition speeds are currently being developed with incorporation of a swept-source MIOCT engine. Further refinements and investigations will be directed toward continued integration for real-time volumetric imaging of surgical maneuvers. Translational Relevance: Ongoing development of seamless MIOCT systems will likely transform surgical visualization, approaches, and decision-making. PMID

  15. Towards a digital model of zebrafish embryogenesis. Integration of cell tracking and gene expression quantification.

    PubMed

    Castro-Gonzalez, Carlos; Luengo-Oroz, Miguel Angel; Douloquin, Louise; Savy, Thierry; Melani, Camilo; Desnoulez, Sophie; Ledesma-Carbayo, Maria Jesus; Bourginey, Paul; Peyrieras, Nadine; Santos, Andres

    2010-01-01

    We elaborate on a general framework composed of a set of computational tools to accurately quantificate cellular position and gene expression levels throughout early zebrafish embryogenesis captured over a time-lapse series of in vivo 3D images. Our modeling strategy involves nuclei detection, cell geometries extraction, automatic gene levels quantification and cell tracking to reconstruct cell trajectories and lineage tree which describe the animal development. Each cell in the embryo is then precisely described at each given time t by a vector composed of the cell 3D spatial coordinates (x; y; z) along with its gene expression level g. This comprehensive description of the embryo development is used to assess the general connection between genetic expression and cell movement. We also investigate genetic expression propagation between a cell and its progeny in the lineage tree. More to the point, this paper focuses on the evolution of the expression pattern of transcriptional factor goosecoid (gsc) through the gastrulation process between 6 and 9 hours post fertilization (hpf). PMID:21096468

  16. Integration of communications and tracking data processing simulation for space station

    NASA Technical Reports Server (NTRS)

    Lacovara, Robert C.

    1987-01-01

    A simplified model of the communications network for the Communications and Tracking Data Processing System (CTDP) was developed. It was simulated by use of programs running on several on-site computers. These programs communicate with one another by means of both local area networks and direct serial connections. The domain of the model and its simulation is from Orbital Replaceable Unit (ORU) interface to Data Management Systems (DMS). The simulation was designed to allow status queries from remote entities across the DMS networks to be propagated through the model to several simulated ORU's. The ORU response is then propagated back to the remote entity which originated the request. Response times at the various levels were investigated in a multi-tasking, multi-user operating system environment. Results indicate that the effective bandwidth of the system may be too low to support expected data volume requirements under conventional operating systems. Instead, some form of embedded process control program may be required on the node computers.

  17. Cerebral palsy.

    PubMed

    Graham, H Kerr; Rosenbaum, Peter; Paneth, Nigel; Dan, Bernard; Lin, Jean-Pierre; Damiano, Diane L; Becher, Jules G; Gaebler-Spira, Deborah; Colver, Allan; Reddihough, Dinah S; Crompton, Kylie E; Lieber, Richard L

    2016-01-01

    Cerebral palsy is the most common cause of childhood-onset, lifelong physical disability in most countries, affecting about 1 in 500 neonates with an estimated prevalence of 17 million people worldwide. Cerebral palsy is not a disease entity in the traditional sense but a clinical description of children who share features of a non-progressive brain injury or lesion acquired during the antenatal, perinatal or early postnatal period. The clinical manifestations of cerebral palsy vary greatly in the type of movement disorder, the degree of functional ability and limitation and the affected parts of the body. There is currently no cure, but progress is being made in both the prevention and the amelioration of the brain injury. For example, administration of magnesium sulfate during premature labour and cooling of high-risk infants can reduce the rate and severity of cerebral palsy. Although the disorder affects individuals throughout their lifetime, most cerebral palsy research efforts and management strategies currently focus on the needs of children. Clinical management of children with cerebral palsy is directed towards maximizing function and participation in activities and minimizing the effects of the factors that can make the condition worse, such as epilepsy, feeding challenges, hip dislocation and scoliosis. These management strategies include enhancing neurological function during early development; managing medical co-morbidities, weakness and hypertonia; using rehabilitation technologies to enhance motor function; and preventing secondary musculoskeletal problems. Meeting the needs of people with cerebral palsy in resource-poor settings is particularly challenging. PMID:27188686

  18. Evaluating an Integrated Approach to the Management of Cerebral Palsy. Appendix C: An Analysis of the Evaluation and Follow-up Data from the Institute for Movement Therapy in Budapest, Hungary. Volume IV of IV. Final Report.

    ERIC Educational Resources Information Center

    Heal, Laird W.

    The appendix analyzed evaluation and followup data from the Institute for Movement Therapy whose procedures the Integrated Management of Cerebral Palsy project attempted to replicate. Examined were data from over a 15 year period for 866 patients treated for a broad range of motoric disabilities. Data concerned independence in eating dressing,…

  19. Particle-Tracking within an Ultra-High-Resolution Urban Domain Integrated with Best Management Practices

    NASA Astrophysics Data System (ADS)

    Lopez, S. R.; Maxwell, R. M.

    2014-12-01

    Best management practices (BMPs) are used to offset the impacts of urban developments known to decrease aquifer recharge, alter drainage networks, change feedbacks to the atmosphere and enhance contaminant transport. To evaluate the effectiveness of BMPs (i.e. engineered wetlands, grass swales, permeable pavements, etc.), a high-resolution study of these processes can be performed in the field using timely monitored instruments, or conceptually-based hydrologic models. However, this approach requires advancing stormwater modeling techniques using high performance computing. The goal of this work is to develop a novel approach to evaluate BMP implementation using an ultra-high-resolution domain and ParFlow, a physically-based hydrologic model that simulates surface and subsurface water interactions. This study domain is located in Aurora, CO, an area that experienced over 200% urban growth over the last 30 years. The ultra-high-resolution domain was constructed using LIDAR imagery and consisted of 1m x 1m horizontal resolution over a ~7.7 km by 2.1 km lateral extent up to 2 m in the subsurface, with a domain totaling more than 3x106unknowns. Three storm events (wet, dry and normal) were simulated with two pavement types, permeable (K=0.18 mhr-1,Φ=0.1) and impermeable (K=0.0018 mhr-1, Φ=0.06), amounting to 6 simulation scenarios. We investigated changes to stormwater routing and infiltration with and without BMP implementation. Contaminant transport was performed using SLIM-FAST, a Lagrangian, particle tracking approach that allows for complex, contaminant-loading scenarios common in the urban environment. Preliminary results show delayed particle movement within impermeable pavement scenarios and particle trapping along the gutters and rooftop locations. This approach is useful for evaluating the effectiveness of BMPs in trapping and reducing concentrations of emerging contaminants of concern within urban environments.

  20. Therapeutic interventions in cerebral palsy.

    PubMed

    Patel, Dilip R

    2005-11-01

    Various therapeutic interventions have been used in the management of children with cerebral palsy. Traditional physiotherapy and occupational therapy are widely used interventions and have been shown to be of benefit in the treatment of cerebral palsy. Evidence in support of the effectiveness of the neurodevelopmental treatment is equivocal at best. There is evidence to support the use and effectiveness of neuromuscular electrical stimulation in children with cerebral palsy. The effectiveness of many other interventions used in the treatment of cerebral palsy has not been clearly established based on well-controlled trials. These include: sensory integration, body-weight support treadmill training, conductive education, constraint-induced therapy, hyperbaric oxygen therapy, and the Vojta method. This article provides an overview of salient aspects of popular interventions used in the management of children with cerebral palsy. PMID:16391455

  1. Photoacoustic imaging of cerebral hypoperfusion during acupuncture

    PubMed Central

    Chen, B. Z.; Yang, J. G.; Wu, D.; Zeng, D. W.; Yi, Y.; Yang, N.; Jiang, H. B.

    2015-01-01

    Using acupuncture to treat cerebral hypoperfusion is a hot topic. However, there is a lack of effective tools to clarify the therapeutic effect of acupuncture on cerebral hypoperfusion. Here, we show in a mouse model of cerebral hypoperfusion that photoacoustic tomography (PAT) can noninvasively image cerebral vasculature and track total hemoglobin (HbT) concentration changes in cerebral hypoperfusion with acupuncture stimulation on the YangLingQuan (GB34) point. We measured the changes of HbT concentration and found that the HbT concentration in hypoperfusion regions was clearly lower than that in the control regions when the acupuncture was absent; however, it was significantly increased when the acupuncture was implemented on the GB34 point. We also observed the increase of vessel size and the generation of new vessels in cerebral hypoperfusion during acupuncture. Laser speckle imaging (LSI) was employed to validate some of the PAT findings. PMID:26417495

  2. Motion tracking and electromyography-assisted identification of mirror hand contributions to functional near-infrared spectroscopy images acquired during a finger-tapping task performed by children with cerebral palsy

    PubMed Central

    Hervey, Nathan; Khan, Bilal; Shagman, Laura; Tian, Fenghua; Delgado, Mauricio R.; Tulchin-Francis, Kirsten; Shierk, Angela; Roberts, Heather; Smith, Linsley; Reid, Dahlia; Clegg, Nancy J.; Liu, Hanli; MacFarlane, Duncan; Alexandrakis, George

    2014-01-01

    Abstract. Recent studies have demonstrated functional near-infrared spectroscopy (fNIRS) to be a viable and sensitive method for imaging sensorimotor cortex activity in children with cerebral palsy (CP). However, during unilateral finger tapping, children with CP often exhibit unintended motions in the nontapping hand, known as mirror motions, which confuse the interpretation of resulting fNIRS images. This work presents a method for separating some of the mirror motion contributions to fNIRS images and demonstrates its application to fNIRS data from four children with CP performing a finger-tapping task with mirror motions. Finger motion and arm muscle activity were measured simultaneously with fNIRS signals using motion tracking and electromyography (EMG), respectively. Subsequently, subject-specific regressors were created from the motion capture or EMG data and independent component analysis was combined with a general linear model to create an fNIRS image representing activation due to the tapping hand and one image representing activation due to the mirror hand. The proposed method can provide information on how mirror motions contribute to fNIRS images, and in some cases, it helps remove mirror motion contamination from the tapping hand activation images. PMID:26157980

  3. Progress Monitoring in an Integrated Health Care System: Tracking Behavioral Health Vital Signs.

    PubMed

    Steinfeld, Bradley; Franklin, Allie; Mercer, Brian; Fraynt, Rebecca; Simon, Greg

    2016-05-01

    Progress monitoring implementation in an integrated health care system is a complex process that must address factors such as measurement, technology, delivery system care processes, patient needs and provider requirements. This article will describe how one organization faced these challenges by identifying the key decision points (choice of measure, process for completing rating scale, interface with electronic medical record and clinician engagement) critical to implementation. Qualitative and quantitative data will be presented describing customer and stakeholder satisfaction with the mental health progress monitoring tool (MHPMT) as well as organizational performance with key measurement targets. PMID:25840521

  4. Performance of third-year primary-care-track students in an integrated curriculum at Case Western Reserve University.

    PubMed

    Lewin, L O; Papp, K K; Hodder, S L; Workings, M G; Wolfe, L; Glover, P; Headrick, L A

    1999-01-01

    In 1994, Case Western Reserve University School of Medicine established a Primary Care Track (PCT) with an integrated curriculum as part of The Robert Wood Johnson Foundation's Generalist Physician Initiative. This study compared the performance of the first cohort of students to participate in the PCT third year with that of their classmates and determined student attitudes toward their experiences. The performances of 24 PCT and 81 traditional students on the Medical School Admissions Test (MCAT) and the United States Medical Licensure Examination (USMLE) Step 1 and 2 were compared using analysis of variance. Grades on the six core clerkships were compared using chi-square analysis. Performances of the PCT students and a subset of traditional students on the generalist school's objective structured clinical exam (OSCE) were compared using multivariate analysis. The students reported their perceptions on a questionnaire. The traditional students had significantly higher scores on the physical science section of the MCAT and on the USMLE Step 1, but at the end of year three, their USMLE Step 2 scores did not differ. Grade distributions in the core clerkships did not differ, except in psychiatry, where the PCT students received honors significantly more often. The PCT students had a lower mean score on the internal medicine National Board of Medicine Examiners shelf exam but performed better on the generalist OSCE exam. A majority of PCT students reported that they would choose the integrated third year again and recommend it to others. PMID:9934315

  5. Validation of GPS derived integrated water vapor with microwave radiometer measurements in zenith and satellite tracking mode

    NASA Astrophysics Data System (ADS)

    Heise, Stefan; Shangguan, Ming; Deng, Zhiguo; Dick, Galina; Wickert, Jens; Zus, Florian

    2015-04-01

    Reliable and precise water vapour measurements are important for both, numerical weather prediction and climatological studies. In this context, zenith and slant total delay (ZTD, STD) data from Global Positioning System (GPS) ground observations provide a valuable source of integrated water vapour (IWV) information with high potential for assimilation to numerical weather models and nowcasting applications but also for climatological analysis of longer GPS IWV time series. Therefore it is important to validate the accuracy of GPS IWV with independent observations. For this purpose, in 2012 GFZ started to operate a water vapour radiometer (WVR) in vicinity of the Potsdam GPS station. It measures the absorption lines of atmospheric water vapour and oxygen at 14 frequency channels in the 22-58 GHz range and provides among others integrated water vapour measurements along the respective line of sight. Besides zenith IWV measurements the radiometer is operated in GPS satellite tracking mode enabling direct comparisons with the nearby GPS slant IWV observations (processed at GFZ). In this study we present validation results of GPS slant and zenith IWV data with the collocated radiometer observations. The validation covers all seasons including dry and wet humidity conditions. We address relations between the GPS-WVR differences and corresponding observation conditions that might have influence on the comparison results (elevation angles, ground pressure and temperature, atmospheric humidity).

  6. Cerebral Palsy

    MedlinePlus

    ... Español (Spanish) Recommend on Facebook Tweet Share Compartir Cerebral palsy (CP) is a group of disorders that affect a ... ability to move and maintain balance and posture. CP is the most common motor disability in childhood. ...

  7. Cerebral Arteriosclerosis

    MedlinePlus

    ... Cerebral arteriosclerosis is the result of thickening and hardening of the walls of the arteries in the ... cause an ischemic stroke. When the thickening and hardening is uneven, arterial walls can develop bulges (called ...

  8. Cerebral angiography

    MedlinePlus

    ... Cerebral angiography is done in the hospital or radiology center. You lie on an x-ray table. ... be done in preparation for medical treatment (interventional radiology procedures) by way of certain blood vessels. What ...

  9. Integrating smart-phone based momentary location tracking with fixed site air quality monitoring for personal exposure assessment.

    PubMed

    Su, Jason G; Jerrett, Michael; Meng, Ying-Ying; Pickett, Melissa; Ritz, Beate

    2015-02-15

    Epidemiological studies investigating relationships between environmental exposures from air pollution and health typically use residential addresses as a single point for exposure, while environmental exposures in transit, at work, school or other locations are largely ignored. Personal exposure monitors measure individuals' exposures over time; however, current personal monitors are intrusive and cannot be operated at a large scale over an extended period of time (e.g., for a continuous three months) and can be very costly. In addition, spatial locations typically cannot be identified when only personal monitors are used. In this paper, we piloted a study that applied momentary location tracking services supplied by smart phones to identify an individual's location in space-time for three consecutive months (April 28 to July 28, 2013) using available Wi-Fi networks. Individual exposures in space-time to the traffic-related pollutants Nitrogen Oxides (NOX) were estimated by superimposing an annual mean NOX concentration surface modeled using the Land Use Regression (LUR) modeling technique. Individual's exposures were assigned to stationary (including home, work and other stationary locations) and in-transit (including commute and other travel) locations. For the individual, whose home/work addresses were known and the commute route was fixed, it was found that 95.3% of the time, the individual could be accurately identified in space-time. The ambient concentration estimated at the home location was 21.01 ppb. When indoor/outdoor infiltration, indoor sources of air pollution and time spent outdoors were taken into consideration, the individual's cumulative exposures were 28.59 ppb and 96.49 ppb, assuming a respective indoor/outdoor ratio of 1.33 and 5.00. Integrating momentary location tracking services with fixed-site field monitoring, plus indoor-outdoor air exchange calibration, makes exposure assessment of a very large population over an extended time period

  10. Cerebral Palsy (For Parents)

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy Cerebral Palsy KidsHealth > For Parents > Cerebral Palsy Print A A ... kids who are living with the condition. About Cerebral Palsy Cerebral palsy is one of the most common ...

  11. Cerebral palsy - resources

    MedlinePlus

    Resources - cerebral palsy ... The following organizations are good resources for information on cerebral palsy : National Institute of Neurological Disorders and Stroke -- www.ninds.nih.gov/disorders/cerebral_palsy/cerebral_palsy. ...

  12. Integration of a vision-based tracking platform, visual instruction, and error analysis models for an efficient billiard training system

    NASA Astrophysics Data System (ADS)

    Shih, Chihhsiong; Hsiung, Pao-Ann; Wan, Chieh-Hao; Koong, Chorng-Shiuh; Liu, Tang-Kun; Yang, Yuanfan; Lin, Chu-Hsing; Chu, William Cheng-Chung

    2009-02-01

    A billiard ball tracking system is designed to combine with a visual guide interface to instruct users for a reliable strike. The integrated system runs on a PC platform. The system makes use of a vision system for cue ball, object ball and cue stick tracking. A least-squares error calibration process correlates the real-world and the virtual-world pool ball coordinates for a precise guidance line calculation. Users are able to adjust the cue stick on the pool table according to a visual guidance line instruction displayed on a PC monitor. The ideal visual guidance line extended from the cue ball is calculated based on a collision motion analysis. In addition to calculating the ideal visual guide, the factors influencing selection of the best shot among different object balls and pockets are explored. It is found that a tolerance angle around the ideal line for the object ball to roll into a pocket determines the difficulty of a strike. This angle depends in turn on the distance from the pocket to the object, the distance from the object to the cue ball, and the angle between these two vectors. Simulation results for tolerance angles as a function of these quantities are given. A selected object ball was tested extensively with respect to various geometrical parameters with and without using our integrated system. Players with different proficiency levels were selected for the experiment. The results indicate that all players benefit from our proposed visual guidance system in enhancing their skills, while low-skill players show the maximum enhancement in skill with the help of our system. All exhibit enhanced maximum and average hit-in rates. Experimental results on hit-in rates have shown a pattern consistent with that of the analysis. The hit-in rate is thus tightly connected with the analyzed tolerance angles for sinking object balls into a target pocket. These results prove the efficiency of our system, and the analysis results can be used to attain an

  13. Interleaved imaging of cerebral hemodynamics and blood flow index to monitor ischemic stroke and treatment in rat by volumetric diffuse optical tomography.

    PubMed

    Lin, Zi-Jing; Ren, Ming; Li, Lin; Liu, Yueming; Su, Jianzhong; Yang, Shao-Hua; Liu, Hanli

    2014-01-15

    Diffuse optical tomography (DOT) has been used by several groups to assess cerebral hemodynamics of cerebral ischemia in humans and animals. In this study, we combined DOT with an indocyanine green (ICG)-tracking method to achieve interleaved images of cerebral hemodynamics and blood flow index (BFI) using two middle cerebral artery occlusion (MCAO) rat models. To achieve volumetric images with high-spatial resolution, we first integrated a depth compensation algorithm (DCA) with a volumetric mesh-based rat head model to generate three-dimensional (3D) DOT on a rat brain atlas. Then, the experimental DOT data from two rat models were collected using interleaved strategy for cerebral hemodynamics and BFI during and after ischemic stroke, with and without a thrombolytic therapy for the embolic MCAO model. The acquired animal data were further analyzed using the integrated rat-atlas-guided DOT method to form time-evolving 3D images of both cerebral hemodynamics and BFI. In particular, we were able to show and identify therapeutic outcomes of a thrombolytic treatment applied to the embolism-induced ischemic model. This paper demonstrates that volumetric DOT is capable of providing high-quality, interleaved images of cerebral hemodynamics and blood perfusion in small animals during and after ischemic stroke, with excellent 3D visualization and quantifications. PMID:23872158

  14. Interleaved imaging of cerebral hemodynamics and blood flow index to monitor ischemic stroke and treatment in rat by volumetric diffuse optical tomography

    PubMed Central

    Lin, Zi-Jing; Ren, Ming; Li, Lin; Liu, Yueming; Su, Jianzhong; Yang, Shao-Hua; Liu, Hanli

    2013-01-01

    Diffuse optical tomography (DOT) has been used by several groups to assess cerebral hemodynamics of cerebral ischemia in humans and animals. In this study, we combined DOT with an indocyanine green (ICG)-tracking method to achieve interleaved images of cerebral hemodynamics and blood flow index (BFI) using two middle cerebral artery occlusion (MCAO) rat models. To achieve volumetric images with high-spatial resolution, we first integrated a depth compensation algorithm (DCA) with a volumetric mesh-based rat head model to generate three-dimensional (3D) DOT on a rat brain atlas. Then, the experimental DOT data from two rat models were collected using interleaved strategy for cerebral hemodynamics and BFI during and after ischemic stroke, with and without a thrombolytic therapy for the embolic MCAO model. The acquired animal data were further analyzed using the integrated rat-atlas-guided DOT method to form time-evolving 3D images of both cerebral hemodynamics and BFI. In particular, we were able to show and identify therapeutic outcomes of a thrombolytic treatment applied to the embolism-induced ischemic model. This paper demonstrates that volumetric DOT is capable of providing high-quality, interleaved images of cerebral hemodynamics and blood perfusion in small animals during and after ischemic stroke, with excellent 3D visualization and quantifications. PMID:23872158

  15. Feasibility of integrating a multi-camera optical tracking system in intra-operative electron radiation therapy scenarios

    NASA Astrophysics Data System (ADS)

    García-Vázquez, V.; Marinetto, E.; Santos-Miranda, J. A.; Calvo, F. A.; Desco, M.; Pascau, J.

    2013-12-01

    Intra-operative electron radiation therapy (IOERT) combines surgery and ionizing radiation applied directly to an exposed unresected tumour mass or to a post-resection tumour bed. The radiation is collimated and conducted by a specific applicator docked to the linear accelerator. The dose distribution in tissues to be irradiated and in organs at risk can be planned through a pre-operative computed tomography (CT) study. However, surgical retraction of structures and resection of a tumour affecting normal tissues significantly modify the patient's geometry. Therefore, the treatment parameters (applicator dimension, pose (position and orientation), bevel angle, and beam energy) may require the original IOERT treatment plan to be modified depending on the actual surgical scenario. We propose the use of a multi-camera optical tracking system to reliably record the actual pose of the IOERT applicator in relation to the patient's anatomy in an environment prone to occlusion problems. This information can be integrated in the radio-surgical treatment planning system in order to generate a real-time accurate description of the IOERT scenario. We assessed the accuracy of the applicator pose by performing a phantom-based study that resembled three real clinical IOERT scenarios. The error obtained (2 mm) was below the acceptance threshold for external radiotherapy practice, thus encouraging future implementation of this approach in real clinical IOERT scenarios.

  16. Field calculations, single-particle tracking, and beam dynamics with space charge in the electron lens for the Fermilab Integrable Optics Test Accelerator

    SciTech Connect

    Noll, Daniel; Stancari, Giulio

    2015-11-17

    An electron lens is planned for the Fermilab Integrable Optics Test Accelerator as a nonlinear element for integrable dynamics, as an electron cooler, and as an electron trap to study space-charge compensation in rings. We present the main design principles and constraints for nonlinear integrable optics. A magnetic configuration of the solenoids and of the toroidal section is laid out. Singleparticle tracking is used to optimize the electron path. Electron beam dynamics at high intensity is calculated with a particle-in-cell code to estimate current limits, profile distortions, and the effects on the circulating beam. In the conclusions, we summarize the main findings and list directions for further work.

  17. Determining origin in a migratory marine vertebrate: a novel method to integrate stable isotopes and satellite tracking

    USGS Publications Warehouse

    Vander Zanden, Hannah B.; Tucker, Anton D.; Hart, Kristen M.; Lamont, Margaret M.; Fujisaki, Ikuko; Addison, David S.; Mansfield, Katherine L.; Phillips, Katrina F.; Wunder, Michael B.; Bowen, Gabriel J.; Pajuelo, Mariela; Bolten, Alan B.; Bjorndal, Karen A.

    2015-01-01

    Stable isotope analysis is a useful tool to track animal movements in both terrestrial and marine environments. These intrinsic markers are assimilated through the diet and may exhibit spatial gradients as a result of biogeochemical processes at the base of the food web. In the marine environment, maps to predict the spatial distribution of stable isotopes are limited, and thus determining geographic origin has been reliant upon integrating satellite telemetry and stable isotope data. Migratory sea turtles regularly move between foraging and reproductive areas. Whereas most nesting populations can be easily accessed and regularly monitored, little is known about the demographic trends in foraging populations. The purpose of the present study was to examine migration patterns of loggerhead nesting aggregations in the Gulf of Mexico (GoM), where sea turtles have been historically understudied. Two methods of geographic assignment using stable isotope values in known-origin samples from satellite telemetry were compared: 1) a nominal approach through discriminant analysis and 2) a novel continuous-surface approach using bivariate carbon and nitrogen isoscapes (isotopic landscapes) developed for this study. Tissue samples for stable isotope analysis were obtained from 60 satellite-tracked individuals at five nesting beaches within the GoM. Both methodological approaches for assignment resulted in high accuracy of foraging area determination, though each has advantages and disadvantages. The nominal approach is more appropriate when defined boundaries are necessary, but up to 42% of the individuals could not be considered in this approach. All individuals can be included in the continuous-surface approach, and individual results can be aggregated to identify geographic hotspots of foraging area use, though the accuracy rate was lower than nominal assignment. The methodological validation provides a foundation for future sea turtle studies in the region to inexpensively

  18. Determining origin in a migratory marine vertebrate: a novel method to integrate stable isotopes and satellite tracking.

    PubMed

    Zanden, Hannah B Vander; Tucker, Anton D; Hart, Kristen M; Lamont, Margaret M; Fuisaki, Ikuko; Addison, David; Mansfield, Katherine L; Phillips, Katrina F; Wunder, Michael B; Bowen, Gabriel J; Pajuelo, Mariela; Bolten, Alan B; Bjorndal, Karen A

    2015-03-01

    Stable isotope analysis is a useful tool to track animal movements in both terrestrial and marine environments. These intrinsic markers are assimilated through the diet and may exhibit spatial gradients as a result of biogeochemical processes at the base of the food web. In the marine environment, maps to predict the spatial distribution of stable isotopes are limited, and thus determining geographic origin has been reliant upon integrating satellite telemetry and stable isotope data. Migratory sea turtles regularly move between foraging and reproductive areas. Whereas most nesting populations can be easily accessed and regularly monitored, little is known about the demographic trends in foraging populations. The purpose of the present study was to examine migration patterns of loggerhead nesting aggregations in the Gulf of Mexico (GoM), where sea turtles have been historically understudied. Two methods of geographic assignment using stable isotope values in known-origin samples from satellite telemetry were compared: (1) a nominal approach through discriminant analysis and (2) a novel continuous-surface approach using bivariate carbon and nitrogen isoscapes (isotopic landscapes) developed for this study. Tissue samples for stable isotope analysis were obtained from 60 satellite-tracked individuals at five nesting beaches within the GoM. Both methodological approaches for assignment resulted in high accuracy of foraging area determination, though each has advantages and disadvantages. The nominal approach is more appropriate when defined boundaries are necessary, but up to 42% of the individuals could not be considered in this approach. All individuals can be included in the continuous-surface approach, and individual results can be aggregated to identify geographic hotspots of foraging area use, though the accuracy rate was lower than nominal assignment. The methodological validation provides a foundation for future sea turtle studies in the region to

  19. Integration of Real-Time Internal Electromagnetic Position Monitoring Coupled With Dynamic Multileaf Collimator Tracking: An Intensity-Modulated Radiation Therapy Feasibility Study

    SciTech Connect

    Smith, Ryan L.; Sawant, Amit PhD.; Santanam, Lakshmi PhD.; Venkat, Raghu B.; Newell, Laurence J.; Cho, Byung-chul; Poulsen, Per; Catell, Herbert; Keall, Paul J.; Parikh, Parag J.

    2009-07-01

    Purpose: Continuous tumor position measurement coupled with a tumor tracking system would result in a highly accurate radiation therapy system. Previous internal position monitoring systems have been limited by fluoroscopic radiation dose and low delivery efficiency. We aimed to incorporate a continuous, electromagnetic, three-dimensional position tracking system (Calypso 4D Localization System) with a dynamic multileaf collimator (DMLC)-based dose delivery system. Methods and Materials: A research version of the Calypso System provided real-time position of three Beacon transponders. These real-time three-dimensional positions were sent to research MLC controller with a motion-tracking algorithm that changed the planned leaf sequence. Electromagnetic transponders were embedded in a solid water film phantom that moved with patient lung trajectories while being irradiated with two different plans: a step-and-shoot intensity-modulated radiation therapy (S-IMRT) field and a dynamic IMRT (D-IMRT) field. Dosimetric results were recorded under three conditions: no intervention, DMLC tracking, and a spatial gating system. Results: Dosimetric accuracy was comparable for gating and DMLC tracking. Failure rates for gating/DMLC tracking are as follows: {+-}3 cGy 10.9/ 7.5% for S-IMRT, 3.3/7.2% for D-IMRT; gamma (3mm/3%) 0.2/1.2% for S-IMRT, 0.2/0.2% for D-IMRT. DMLC tracking proved to be as efficient as standard delivery, with a two- to fivefold efficiency increase over gating. Conclusions: Real-time target position information was successfully integrated into a DMLC effector system to modify dose delivery. Experimental results show both comparable dosimetric accuracy as well as improved efficiency compared with spatial gating.

  20. Integrated Electroosmotic Perfusion of Tissue with Online Microfluidic Analysis to Track the Metabolism of Cystamine, Pantethine and Coenzyme A

    PubMed Central

    Wu, Juanfang; Sandberg, Mats; Weber, Stephen G.

    2014-01-01

    We have developed an approach that integrates electroosmotic perfusion of tissue with a substrate-containing solution and online microfluidic analysis of products, in this case thiols. Using this approach we have tracked the metabolism of cystamine, pantethine and CoA in the extracellular space of organotypic hippocampal slice cultures (OHSCs). Currently, little is known about coenzyme A (CoA) biodegradation and even less is known about the regulation and kinetic characteristics for this sequential multi-enzyme reaction. We found that the steady state percentage yields of cysteamine from cystamine and pantethine during the transit through OHSCs were 91% ± 4% (SEM) and 0.01%–0.03%, respectively. The large difference in the yields of cysteamine can be used to explain the drugs’ different toxicities and clinical effectiveness against cystinosis. The kinetic parameters of the enzyme reaction catalyzed by the ectoenzyme pantetheinase are KM,C/α = 4.4 ± 1.1 mM and Vmax,C = 29 ± 3 nM/s, where α is the percentage yield of pantethine to pantetheine through disulfide exchange. We estimate that the percentage yield of pantethine to pantetheine through disulfide exchange is approximately 0.5%. Based on the formation rate of cysteamine in the OHSCs, we obtained the overall apparent Michaelis constant and maximum reaction rate for sequential, extracellular CoA degradation in an in situ environment, which are K′M = 16 ± 4 μM, V′max = 7.1 ± 0.5 nM/s. Kinetic parameters obtained in situ, although difficult to measure, are better representations of the biochemical flux in the living organism than those from isolated enzymes in vitro. PMID:24215585

  1. White matter integrity, hippocampal volume, and cognitive performance of a world-famous nonagenarian track-and-field athlete.

    PubMed

    Burzynska, A Z; Wong, C N; Chaddock-Heyman, L; Olson, E A; Gothe, N P; Knecht, A; Voss, M W; McAuley, E; Kramer, A F

    2016-01-01

    Physical activity (PA) and cardiorespiratory fitness (CRF) are associated with successful brain and cognitive aging. However, little is known about the effects of PA, CRF, and exercise on the brain in the oldest-old. Here we examined white matter (WM) integrity, measured as fractional anisotropy (FA) and WM hyperintensity (WMH) burden, and hippocampal (HIPP) volume of Olga Kotelko (1919-2014). Olga began training for competitions at age of 77 and as of June 2014 held over 30 world records in her age category in track-and-field. We found that Olga's WMH burden was larger and the HIPP was smaller than in the reference sample (58 healthy low-active women 60-78 years old), and her FA was consistently lower in the regions overlapping with WMH. Olga's FA in many normal-appearing WM regions, however, did not differ or was greater than in the reference sample. In particular, FA in her genu corpus callosum was higher than any FA value observed in the reference sample. We speculate that her relatively high FA may be related to both successful aging and the beneficial effects of exercise in old age. In addition, Olga had lower scores on memory, reasoning and speed tasks than the younger reference sample, but outperformed typical adults of age 90-95 on speed and memory. Together, our findings open the possibility of old-age benefits of increasing PA on WM microstructure and cognition despite age-related increase in WMH burden and HIPP shrinkage, and add to the still scarce neuroimaging data of the healthy oldest-old (>90 years) adults. PMID:26237526

  2. Integrated electroosmotic perfusion of tissue with online microfluidic analysis to track the metabolism of cystamine, pantethine, and coenzyme A.

    PubMed

    Wu, Juanfang; Sandberg, Mats; Weber, Stephen G

    2013-12-17

    We have developed an approach that integrates electroosmotic perfusion of tissue with a substrate-containing solution and online microfluidic analysis of products, in this case thiols. Using this approach we have tracked the metabolism of cystamine, pantethine and CoA in the extracellular space of organotypic hippocampal slice cultures (OHSCs). Currently, little is known about coenzyme A (CoA) biodegradation and even less is known about the regulation and kinetic characteristics for this sequential multienzyme reaction. We found that the steady state percentage yields of cysteamine from cystamine and pantethine during the transit through OHSCs were 91% ± 4% (SEM) and 0.01%-0.03%, respectively. The large difference in the yields of cysteamine can be used to explain the drugs' different toxicities and clinical effectiveness against cystinosis. The kinetic parameters of the enzyme reaction catalyzed by the ectoenzyme pantetheinase are KM,C/α = 4.4 ± 1.1 mM and Vmax,C = 29 ± 3 nM/s, where α is the percentage yield of pantethine to pantetheine through disulfide exchange. We estimate that the percentage yield of pantethine to pantetheine through disulfide exchange is approximately 0.5%. Based on the formation rate of cysteamine in the OHSCs, we obtained the overall apparent Michaelis constant and maximum reaction rate for sequential, extracellular CoA degradation in an in situ environment, which are K'M = 16 ± 4 μM, V'max = 7.1 ± 0.5 nM/s. Kinetic parameters obtained in situ, although difficult to measure, are better representations of the biochemical flux in the living organism than those from isolated enzymes in vitro. PMID:24215585

  3. Genetics Home Reference: cerebral cavernous malformation

    MedlinePlus

    ... R, Awad IA, Ginsberg MH. Cerebral cavernous malformations proteins inhibit Rho kinase to stabilize vascular integrity. J Exp Med. 2010 Apr 12;207(4):881-96. doi: 10.1084/jem.20091258. Epub 2010 Mar 22. Citation on ... CCM1 and CCM2 protein interactions in cell signaling: implications for cerebral cavernous ...

  4. Employees with Cerebral Palsy

    MedlinePlus

    ... Resources Home | Accommodation and Compliance Series: Employees with Cerebral Palsy (CP) By Eddie Whidden, MA Preface Introduction Information About ... SOAR) at http://AskJAN.org/soar. Information about Cerebral Palsy (CP) What is CP? Cerebral palsy is a ...

  5. Cerebral Aneurysms Fact Sheet

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS Cerebral Aneurysms Fact Sheet See a list of all NINDS ... I get more information? What is a cerebral aneurysm? A cerebral aneurysm (also known as an intracranial ...

  6. Motor control deficits of orofacial muscles in cerebral palsy.

    PubMed Central

    Vaughan, C W; Neilson, P D; O'Dwyer, N J

    1988-01-01

    Voluntary control of the masseter and orbicularis oris superioris muscles was examined in able bodied and cerebral palsied subjects using visual tracking tasks. A smoothed measure of muscle activity (the full-wave rectified and low-pass filtered electromyogram) was presented as a marker on a computer display screen and the subjects could control the vertical position of the marker by voluntarily altering the level of isometric contraction of one of the muscles. A target marker was also displayed on the screen and the subjects were required to follow or "track" the irregular movements of this target with the response marker. Their success in aligning the response marker with the target was analysed for these orofacial muscles. The masseter is influenced by muscle spindle based reflexes, while the orbicularis oris superioris lacks such reflex control. The cerebral palsied subjects displayed similarly poor control over both muscles, implying that their voluntary motor deficits are not related to abnormal muscle spindle based reflexes. It is suggested that the impairment may be related to perceptual-motor integration. PMID:3379427

  7. Tracking filter algorithm for automatic video tracking

    NASA Astrophysics Data System (ADS)

    McEver, Mark A.; Kimbrell, James E.

    2006-05-01

    In addition to servo control and power amplification, motion control systems for optical tracking pedestals feature capabilities such as electro-optical tracking using an integrated Automatic Video Tracker (AVT) card. An electro-optical system tracking loop is comprised of sensors mounted on a pointing pedestal, an AVT that detects a target in the sensor imagery, and a tracking filter algorithm that commands the pedestal to follow the target. The tracking filter algorithm receives the target boresight error from the AVT and calculates motion demands for the pedestal servo controller. This paper presents a tracking algorithm based on target state estimation using a Kalman filter. The servo demands are based on calculating the Kalman filter state estimate from absolute line-of-sight angles to the target. Simulations are used to compare its performance to tracking loops without tracking filters, and to other tracking filter algorithms, such as rate feedback loops closed around boresight error. Issues such as data latency and sensor alignment error are discussed.

  8. Integration of a road network into a radar ground moving target tracking (GMTT) system and its performance evaluation

    NASA Astrophysics Data System (ADS)

    Blackman, Sam; Fong, Kathy; Carroll, Douglas E.; Lancaster, Justin; Dempster, Robert

    2009-08-01

    This paper discusses the application of multiple hypothesis tracking (MHT) to the processing of ground target data collected with a long range surveillance radar. A key element in the successful tracking of ground targets is the use of road networks. Thus, the paper begins with an overview of the alternative approaches that have been considered for incorporating road data into a ground target tracker and then it gives a detailed description of the methods that have been chosen. The major design issues to be addressed include the manner in which road filter models are included into a Variable-Structure Interacting Multiple Model (IMM) filtering scheme, how the road filter models are chosen to handle winding roads and intersections, and the tracking of targets that go on and off-road. Performance will be illustrated using simulated data and real data collected from a large surveillance area with a GMTI radar. The area considered contains regions of heavy to moderate target densities and clutter. Since the real data included only targets of opportunity (TOO), it was necessary to define metrics to evaluate relative performance as alternative tracking methods/parameters are considered. These metrics are discussed and comparative results are presented.

  9. Using Eye Tracking to Investigate Semantic and Spatial Representations of Scientific Diagrams during Text-Diagram Integration

    ERIC Educational Resources Information Center

    Jian, Yu-Cin; Wu, Chao-Jung

    2015-01-01

    We investigated strategies used by readers when reading a science article with a diagram and assessed whether semantic and spatial representations were constructed while reading the diagram. Seventy-one undergraduate participants read a scientific article while tracking their eye movements and then completed a reading comprehension test. Our…

  10. Cerebral malaria.

    PubMed

    Postels, Douglas G; Birbeck, Gretchen L

    2013-01-01

    Malaria, the most significant parasitic disease of man, kills approximately one million people per year. Half of these deaths occur in those with cerebral malaria (CM). The World Health Organization (WHO) defines CM as an otherwise unexplained coma in a patient with malarial parasitemia. Worldwide, CM occurs primarily in African children and Asian adults, with the vast majority (greater than 90%) of cases occurring in children 5 years old or younger in sub-Saharan Africa. The pathophysiology of the disease is complex and involves infected erythrocyte sequestration, cerebral inflammation, and breakdown of the blood-brain barrier. A recently characterized malarial retinopathy is visual evidence of Plasmodium falciparum's pathophysiological processes occurring in the affected patient. Treatment consists of supportive care and antimalarial administration. Thus far, adjuvant therapies have not been shown to improve mortality rates or neurological outcomes in children with CM. For those who survive CM, residual neurological abnormalities are common. Epilepsy, cognitive impairment, behavioral disorders, and gross neurological deficits which include motor, sensory, and language impairments are frequent sequelae. Primary prevention strategies, including bed nets, vaccine development, and chemoprophylaxis, are in varied states of development and implementation. Continuing efforts to find successful primary prevention options and strategies to decrease neurological sequelae are needed. PMID:23829902

  11. Toward Submillimeter Accuracy in the Management of Intrafraction Motion: The Integration of Real-Time Internal Position Monitoring and Multileaf Collimator Target Tracking

    SciTech Connect

    Sawant, Amit Smith, Ryan L.; Venkat, Raghu B.; Santanam, Lakshmi; Cho, Byungchul; Poulsen, Per; Cattell, Herbert; Newell, Laurence J.; Parikh, Parag; Keall, Paul J.

    2009-06-01

    Purpose: We report on an integrated system for real-time adaptive radiation delivery to moving tumors. The system combines two promising technologies-three-dimensional internal position monitoring using implanted electromagnetically excitable transponders and corresponding real-time beam adaptation using a dynamic multileaf collimator (DMLC). Methods and Materials: In a multi-institutional academic and industrial collaboration, a research version of the Calypso position monitoring system was integrated with a DMLC-based four-dimensional intensity-modulated radiotherapy delivery system using a Varian 120-leaf multileaf collimator (MLC). Two important determinants of system performance-latency (i.e., elapsed time between target motion and MLC response) and geometric accuracy-were investigated. Latency was quantified by acquiring continuous megavoltage X-ray images of a moving phantom (with embedded transponders) that was tracked in real time by a circular MLC field. The latency value was input into a motion prediction algorithm within the DMLC tracking system. Geometric accuracy was calculated as the root-mean-square positional error between the target and the centroid of the MLC aperture for patient-derived three-dimensional motion trajectories comprising two lung tumor traces and one prostate trace. Results: System latency was determined to be approximately 220 milliseconds. Tracking accuracy was observed to be sub-2 mm for the respiratory motion traces and sub-1 mm for prostate motion. Conclusion: We have developed and characterized a research version of a novel four-dimensional delivery system that integrates nonionizing radiation-based internal position monitoring and accurate real-time DMLC-based beam adaptation. This system represents a significant step toward achieving the eventual goal of geometrically ideal dose delivery to moving tumors.

  12. Sample-Wise Aiding in GPS/INS Ultra-Tight Integration for High-Dynamic, High-Precision Tracking.

    PubMed

    Kou, Yanhong; Zhang, Han

    2016-01-01

    By aiding GPS receiver tracking loops with INS estimates of signal dynamics, GPS/INS ultra-tight coupling can improve the navigation performance in challenging environments. Traditionally the INS data are injected into the loops once every loop update interval, which limits the levels of dynamics accommodated. This paper presents a sample-wise aiding method, which interpolates the aiding Doppler into each digital sample of the local signal to further eliminate the dynamic errors. The relationship between the tracking error and the aiding rate is derived analytically. Moreover, the effects of sample-wise aiding using linear and spline interpolations are simulated and compared with traditional aiding under different INS data update rates. Finally, extensive tests based on a digital IF (intermediate frequency) signal simulator and a software receiver validate the theoretical equations and demonstrate that the dynamic stress error can be significantly reduced by sample-wise aiding. PMID:27077858

  13. Sample-Wise Aiding in GPS/INS Ultra-Tight Integration for High-Dynamic, High-Precision Tracking

    PubMed Central

    Kou, Yanhong; Zhang, Han

    2016-01-01

    By aiding GPS receiver tracking loops with INS estimates of signal dynamics, GPS/INS ultra-tight coupling can improve the navigation performance in challenging environments. Traditionally the INS data are injected into the loops once every loop update interval, which limits the levels of dynamics accommodated. This paper presents a sample-wise aiding method, which interpolates the aiding Doppler into each digital sample of the local signal to further eliminate the dynamic errors. The relationship between the tracking error and the aiding rate is derived analytically. Moreover, the effects of sample-wise aiding using linear and spline interpolations are simulated and compared with traditional aiding under different INS data update rates. Finally, extensive tests based on a digital IF (intermediate frequency) signal simulator and a software receiver validate the theoretical equations and demonstrate that the dynamic stress error can be significantly reduced by sample-wise aiding. PMID:27077858

  14. [Cerebral palsy].

    PubMed

    Malagón Valdez, Jorge

    2007-01-01

    The term cerebral palsy (CP), is used for a great number of clinical neurological syndromes. The syndromes are characterized by having a common cause, motor defects. It is important, because they can cause a brain damage by presenting motor defects and some associated deficiencies, such as mental deficiency, epilepsy, language and visual defects and pseudobulbar paralysis, with the non-evolving fact. Some authors prefer using terms such as "non-evolving encephalopathies". In the treatment the utility of prevention programs of early stimulation and special rehabilitation methods, and treatment of associated deficiencies such as epilepsy, mental deficiency, language, audition and visual problems, and the attention deficit improve the prognosis in an important way. The prognosis depends on the severity of the disease and the associated manifestations. PMID:18422084

  15. Tracking Architecture Based on Dual-Filter with State Feedback and Its Application in Ultra-Tight GPS/INS Integration

    PubMed Central

    Zhang, Xi; Miao, Lingjuan; Shao, Haijun

    2016-01-01

    If a Kalman Filter (KF) is applied to Global Positioning System (GPS) baseband signal preprocessing, the estimates of signal phase and frequency can have low variance, even in highly dynamic situations. This paper presents a novel preprocessing scheme based on a dual-filter structure. Compared with the traditional model utilizing a single KF, this structure avoids carrier tracking being subjected to code tracking errors. Meanwhile, as the loop filters are completely removed, state feedback values are adopted to generate local carrier and code. Although local carrier frequency has a wide fluctuation, the accuracy of Doppler shift estimation is improved. In the ultra-tight GPS/Inertial Navigation System (INS) integration, the carrier frequency derived from the external navigation information is not viewed as the local carrier frequency directly. That facilitates retaining the design principle of state feedback. However, under harsh conditions, the GPS outputs may still bear large errors which can destroy the estimation of INS errors. Thus, an innovative integrated navigation filter is constructed by modeling the non-negligible errors in the estimated Doppler shifts, to ensure INS is properly calibrated. Finally, field test and semi-physical simulation based on telemetered missile trajectory validate the effectiveness of methods proposed in this paper. PMID:27144570

  16. Tracking Architecture Based on Dual-Filter with State Feedback and Its Application in Ultra-Tight GPS/INS Integration.

    PubMed

    Zhang, Xi; Miao, Lingjuan; Shao, Haijun

    2016-01-01

    If a Kalman Filter (KF) is applied to Global Positioning System (GPS) baseband signal preprocessing, the estimates of signal phase and frequency can have low variance, even in highly dynamic situations. This paper presents a novel preprocessing scheme based on a dual-filter structure. Compared with the traditional model utilizing a single KF, this structure avoids carrier tracking being subjected to code tracking errors. Meanwhile, as the loop filters are completely removed, state feedback values are adopted to generate local carrier and code. Although local carrier frequency has a wide fluctuation, the accuracy of Doppler shift estimation is improved. In the ultra-tight GPS/Inertial Navigation System (INS) integration, the carrier frequency derived from the external navigation information is not viewed as the local carrier frequency directly. That facilitates retaining the design principle of state feedback. However, under harsh conditions, the GPS outputs may still bear large errors which can destroy the estimation of INS errors. Thus, an innovative integrated navigation filter is constructed by modeling the non-negligible errors in the estimated Doppler shifts, to ensure INS is properly calibrated. Finally, field test and semi-physical simulation based on telemetered missile trajectory validate the effectiveness of methods proposed in this paper. PMID:27144570

  17. An integrated pathway interaction network for the combination of four effective compounds from ShengMai preparations in the treatment of cardio-cerebral ischemic diseases

    PubMed Central

    Li, Fang; Lv, Yan-ni; Tan, Yi-sha; Shen, Kai; Zhai, Ke-feng; Chen, Hong-lin; Kou, Jun-ping; Yu, Bo-yang

    2015-01-01

    Aim: SMXZF (a combination of ginsenoside Rb1, ginsenoside Rg1, schizandrin and DT-13) derived from Chinese traditional medicine formula ShengMai preparations) is capable of alleviating cerebral ischemia-reperfusion injury in mice. In this study we used network pharmacology approach to explore the mechanisms of SMXZF in the treatment of cardio-cerebral ischemic diseases. Methods: Based upon the chemical predictors, such as chemical structure, pharmacological information and systems biology functional data analysis, a target-pathway interaction network was constructed to identify potential pathways and targets of SMXZF in the treatment of cardio-cerebral ischemia. Furthermore, the most related pathways were verified in TNF-α-treated human vascular endothelial EA.hy926 cells and H2O2-treated rat PC12 cells. Results: Three signaling pathways including the NF-κB pathway, oxidative stress pathway and cytokine network pathway were demonstrated to be the main signaling pathways. The results from the gene ontology analysis were in accordance with these signaling pathways. The target proteins were found to be associated with other diseases such as vision, renal and metabolic diseases, although they exerted therapeutic actions on cardio-cerebral ischemic diseases. Furthermore, SMXZF not only dose-dependently inhibited the phosphorylation of NF-κB, p50, p65 and IKKα/β in TNF-α-treated EA.hy926 cells, but also regulated the Nrf2/HO-1 pathway in H2O2-treated PC12 cells. Conclusion: NF-κB signaling pathway, oxidative stress pathway and cytokine network pathway are mainly responsible for the therapeutic actions of SMXZF against cardio-cerebral ischemic diseases. PMID:26456587

  18. Computerized tracking of mammography patients: value of a radiology information system integrated with a personal-computer data base.

    PubMed

    Frank, M S; Johnson, J A

    1994-09-01

    OBJECTIVE. We investigated the advantages of using a radiology information system as the primary data source for a mammographic patient-tracking system that is based on a personal-computer local-area network and that requires almost no data entry. HARDWARE AND SOFTWARE. Our mammographic data base is maintained on a file server that provides cross-platform access to both Macintosh and IBM-compatible personal computers. Locally developed software automatically transfers mammographic data from our radiology information system to the file server's mammographic data base. The data transferred include patients' demographics (e.g., hospital identification number, address, referring physician) and the complete mammographic report. With the use of specific terminology, the need for follow-up can be automatically gleaned from the mammographic report and coded within the data base. Graphically oriented, commercially available software provides easy access to this information from any personal computer on our department's network. The software provides considerable flexibility for searching and manipulating the data without the need for customized data-base programming. Redundant data entry and associated errors are drastically reduced, as are personnel requirements for maintaining the system. Relative to most commercial radiology information systems, a personal computer facilitates the steps involved in tracking patients and obtaining highly customized analyses of the mammographic data base. The data in the mammographic data base exactly match those in the hospital's registration data and are easily transferred to other personal-computer programs for ancillary processing. CONCLUSION. This technique is ideal for departments that use a general-purpose radiology information system for mammographic reporting, yet need a more powerful but user-friendly and low-cost method for tracking their mammography patients. PMID:8079872

  19. Fully automated multidimensional reversed-phase liquid chromatography with tandem anion/cation exchange columns for simultaneous global endogenous tyrosine nitration detection, integral membrane protein characterization, and quantitative proteomics mapping in cerebral infarcts.

    PubMed

    Quan, Quan; Szeto, Samuel S W; Law, Henry C H; Zhang, Zaijun; Wang, Yuqiang; Chu, Ivan K

    2015-10-01

    Protein tyrosine nitration (PTN) is a signature hallmark of radical-induced nitrative stress in a wide range of pathophysiological conditions, with naturally occurring abundances at substoichiometric levels. In this present study, a fully automated four-dimensional platform, consisting of high-/low-pH reversed-phase dimensions with two additional complementary, strong anion (SAX) and cation exchange (SCX), chromatographic separation stages inserted in tandem, was implemented for the simultaneous mapping of endogenous nitrated tyrosine-containing peptides within the global proteomic context of a Macaca fascicularis cerebral ischemic stroke model. This integrated RP-SA(C)X-RP platform was initially benchmarked through proteomic analyses of Saccharomyces cerevisiae, revealing extended proteome and protein coverage. A total of 27 144 unique peptides from 3684 nonredundant proteins [1% global false discovery rate (FDR)] were identified from M. fascicularis cerebral cortex tissue. The inclusion of the S(A/C)X columns contributed to the increased detection of acidic, hydrophilic, and hydrophobic peptide populations; these separation features enabled the concomitant identification of 127 endogenous nitrated peptides and 137 transmembrane domain-containing peptides corresponding to integral membrane proteins, without the need for specific targeted enrichment strategies. The enhanced diversity of the peptide inventory obtained from the RP-SA(C)X-RP platform also improved analytical confidence in isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analyses. PMID:26335518

  20. Integration of Dust Prediction Systems and Vegetation Phenology to Track Pollen for Asthma Alerts in Public Health

    NASA Technical Reports Server (NTRS)

    Luvall, Jeffrey; Sprigg, William; Huete, Alfredo; Levetin, Estelle; VandeWater, Peter; Nickovic, Slobodan; Pejanovic, Goran; Budge, Amelia; Heidi Krapfl; Myers, Orrin; Losleben, Mark; Deaton, Tommie; Zelicoff, Alan

    2009-01-01

    Initial efforts to develop a deterministic model for predicting and simulating pollen release and downwind concentration to study dependencies of phenology on meteorology will be discussed. The development of a real-time, rapid response pollen release and transport system as a component of the New Mexico Environmental Public Health Tracking System (EPHTS), is based on meteorological models, NASA Earth science results (ESR), and an in-situ network of phenology cameras. The plan is to detect pollen release verified using ground based atmospheric pollen sampling within a few hours using daily MODIS daa in nearly real-time from Direct Broadcast, similar to the MODIS Rapid Response System for fire detection. As MODIS winds down, the NPOESS-VIIRS sensor will assume daily vegetation monitoring tasks. Also, advancements in geostationary satellites will allow 1km vegetation indices at 15-30 minute intervals. The pollen module in EPHTS will be used to: (1) support public health decisions for asthma and allergy alerts in New Mexico, Texas and Oklahoma; (2) augment the Centers for Disease Control and Prevention (CDC)'s Environmental Public Health Tracking Network (EPHTN); and (3) extend surveillance services to local healthcare providers subscribing to the Syndrome Reporting Information System (SYRIS). Previous studies in NASA's public health applications portfolios provide the infrastructure for this effort. The team is confident that NASA and NOAA ESR data, combined into a verified and validated dust model will yield groundbreaking results using the modified dust model to transport pollen. The growing ESR/health infrastructure is based on results from a rapid prototype scoping effort for pollen detection and simulation carried out by the principal investigators.

  1. United Cerebral Palsy

    MedlinePlus

    ... of UCP blog for the latest updates. United Cerebral Palsy UCP educates, advocates and provides support services to ... Partners Merz Logo Sprint Relay Copyright © 2015 United Cerebral Palsy 1825 K Street NW Suite 600 Washington, DC ...

  2. Cerebral amyloid angiopathy

    MedlinePlus

    Cerebral amyloid angiopathy is a neurological condition in which proteins called amyloid build up on the walls of the arteries ... The cause of cerebral amyloid angiopathy is unknown. Sometimes, it ... Persons with this condition have deposits of amyloid protein ...

  3. Cerebral Contusions and Lacerations

    MedlinePlus

    ... Stretch Additional Content Medical News Cerebral Contusions and Lacerations By James E. Wilberger, MD, Derrick A. Dupre, ... a direct, strong blow to the head. Cerebral lacerations are tears in brain tissue, caused by a ...

  4. FAST TRACK COMMUNICATION: Necessary conditions for classical super-integrability of a certain family of potentials in constant curvature spaces

    NASA Astrophysics Data System (ADS)

    Maciejewski, Andrzej J.; Przybylska, Maria; Yoshida, Haruo

    2010-09-01

    We formulate the necessary conditions for the maximal super-integrability of a certain family of classical potentials defined in the constant curvature two-dimensional spaces. We give examples of homogeneous potentials of degree -2 on {\\bb E}^2 as well as their equivalents on {\\bb S}^2 and {\\bb H}^2 for which these necessary conditions are also sufficient. We show explicit forms of the additional first integrals which can always be chosen as a polynomial with respect to the momenta and which can be of an arbitrary high degree with respect to the momenta.

  5. Self-assembly of high-resolutions PS-b-PMMA block-copolymers: processes capabilities and integration on 300mm track

    NASA Astrophysics Data System (ADS)

    Chevalier, X.; Nicolet, C.; Tiron, R.; Gharbi, A.; Chamiot-Maitral, G.; Jullian, K.; Pimenta-Barros, P.; Argoud, M.; Peyre, J.-L.; Van Spaandonk, R.; Fleury, G.; Hadziioannou, G.; Navarro, C.

    2014-03-01

    Careful control and reproducibility of BCP's synthesis are mandatory parameters to push-down PS-b-PMMA block-copolymer systems toward its lowest dimensions for microelectronic applications. The self-assembly process optimization of different high-resolution cylindrical PS-b-PMMA block-copolymers (i.e. L0 period below 25 nm) is studied to highlight processes-variations as regard to more classical PS-b-PMMA systems while the characterizations of bulk materials provide deeper insights on the parameters addressing the self-assembly of such materials. The integration of a high-resolution BCP on 300 mm track is then studied to check the capabilities of such materials in terms of lithographic applications. CD uniformity measurements in contact hole shrink approach, as well as the transfer of the BCP mask into typical industrial under-layer stacks leading to aggressive features, show that these materials exhibit promising potentials for advanced lithographic nodes.

  6. Aging and Cerebral Palsy.

    ERIC Educational Resources Information Center

    Networker, 1993

    1993-01-01

    This special edition of "The Networker" contains several articles focusing on aging and cerebral palsy (CP). "Aging and Cerebral Palsy: Pathways to Successful Aging" (Jenny C. Overeynder) reports on the National Invitational Colloquium on Aging and Cerebral Palsy held in April 1993. "Observations from an Observer" (Kathleen K. Barrett) describes…

  7. Integration of Dust Prediction Systems and Vegetation Phenology to Track Pollen for Asthma Alerts in Public Health

    NASA Technical Reports Server (NTRS)

    Luvall, Jeffrey C.; Sprigg, W. A.; Huete, A.; Nickovic, S.; Pejanovic, G.; Levetin, E.; Van de water, P.; Myers, O.; Budge, A. M.; Krapfl, H.; Crimmins, T. M.

    2011-01-01

    Pollen can be transported great distances. Van de Water et. al., 2003 reported Juniperus pollen, a significant aeroallergen was transported 200-600 km. Hence local observations of plant phenology may not be consistent with the timing and source of pollen collected by pollen sampling instruments. The DREAM (Dust REgional Atmospheric Model, Yin 2007) is a verified model for atmospheric dust transport modeling using MODIS data products to identify source regions and quantities of dust (Yin 2007). The use of satellite data products for studying phenology is well documented (White and Nemani 2006). We are modifying the DREAM model to incorporate pollen transport. The linkages already exist with DREAM through PHAiRS (Public Health Applications in remote Sensing) to the public health community. This linkage has the potential to fill this data gap so that health effects of pollen can better be tracked for linkage with health outcome data including asthma, respiratory effects, myocardial infarction, and lost work days. DREAM is based on the SKIRON/Eta modeling system and the Eta/NCEP regional atmospheric model. The dust modules of the entire system incorporate the state of the art parameterizations of all the major phases of the atmospheric dust life such as production, diffusion, advection, and removal. These modules also include effects of the particle size distribution on aerosol dispersion. The dust production mechanism is based on the viscous/turbulent mixing, shear-free convection diffusion, and soil moisture. In addition to these sophisticated mechanisms, very high resolution databases, including elevation, soil properties, and vegetation cover are utilized. The DREAM model was modified to use pollen sources instead of dust (PREAM). Pollen release will be estimated based on satellite-derived phenology of Juniperus spp. communities. The MODIS surface reflectance product (MOD09) will provide information on the start of the plant growing season, growth stage, peak

  8. Investigating cerebral oedema using poroelasticity.

    PubMed

    Vardakis, John C; Chou, Dean; Tully, Brett J; Hung, Chang C; Lee, Tsong H; Tsui, Po-Hsiang; Ventikos, Yiannis

    2016-01-01

    Cerebral oedema can be classified as the tangible swelling produced by expansion of the interstitial fluid volume. Hydrocephalus can be succinctly described as the abnormal accumulation of cerebrospinal fluid (CSF) within the brain which ultimately leads to oedema within specific sites of parenchymal tissue. Using hydrocephalus as a test bed, one is able to account for the necessary mechanisms involved in the interaction between oedema formation and cerebral fluid production, transport and drainage. The current state of knowledge about integrative cerebral dynamics and transport phenomena indicates that poroelastic theory may provide a suitable framework to better understand various diseases. In this work, Multiple-Network Poroelastic Theory (MPET) is used to develop a novel spatio-temporal model of fluid regulation and tissue displacement within the various scales of the cerebral environment. The model is applied through two formats, a one-dimensional finite difference - Computational Fluid Dynamics (CFD) coupling framework, as well as a two-dimensional Finite Element Method (FEM) formulation. These are used to investigate the role of endoscopic fourth ventriculostomy in alleviating oedema formation due to fourth ventricle outlet obstruction (1D coupled model) in addition to observing the capability of the FEM template in capturing important characteristics allied to oedema formation, like for instance in the periventricular region (2D model). PMID:26749338

  9. Uncertainty in the tracking and analysis framework integrated assessment: The value of knowing how little you know

    SciTech Connect

    Sonnenblick, R.; Henrion, M.

    1997-12-31

    The Tracking and Analysis Framework (TAF) team has created a model to estimate the economic and ecological effects of the 1990 Clean Air Act Amendment, Title TV. TAF has been coded in the Analytica modeling environment. Analytica allows model variables to be represented as ranges of values, defined as probability distributions. Using Monte Carlo techniques to propagate uncertain values through the model, model results can reflect the uncertainty in model inputs and construction. Rank correlations and elasticities can be computed to gauge model input parameter importance and model sensitivities. These tools allow modelers to view model results in the proper context: Are model results invariant with respect to model component uncertainty and variability? They also help pinpoint the uncertain model components which most affect model results, and may therefore merit additional research to reduce overall model uncertainty. In this paper, we describe the methods used to characterize uncertainty and variability in the TAF model. We also describe the related processes of uncertainty and sensitivity analysis in the TAF model, and relate the results of these processes back to the progressive refinement of the model itself. We use actual results from the Soils-Aquatics, Visibility, and Human Health modules to demonstrate the techniques described.

  10. The EarthCARE space-borne Doppler 94 GHz radar simulator: correction of multiple scattering, aliasing and NUBF and effects of variable along track integration

    NASA Astrophysics Data System (ADS)

    Augustynek, T.; Battaglia, A.; Kollias, P.

    2011-12-01

    The primary goal of this work is to address several challenges related to spaceborne Doppler radars like future the EarthCARE mission and recent developments of data simulation, correction and processing. The 94 GHz Cloud Profiling Radar onboard the ESA EarthCARE mission will be the first radar in space with Doppler capability allowing mean Doppler velocity measurements. This will enable more accurate characterization of clouds and precipitation (classification, retrieval accuracy, dynamics). It is the only instrument of this kind planned for the immediate post-CloudSat era and represents an irreplaceable asset in regards to climate change studies. Meeting the scientific accuracy requirements of vertical motions of 1 m/s, with a horizontal resolution of 1 km, is very challenging. The five key factors that control the performance of spaceborne radar will be discussed, such as: contribution of multiple scattering (MS), attenuation, velocity folding, non uniform beam filling (NUBF) and effects of along track integration of the signal. The research utilizes an end-to-end simulator for spaceborne Doppler radars. The simulator uses a Monte Carlo module which accounts for MS and produces ideal Doppler spectra as measured by a spaceborne radar flying over 3D highly resolved scenes produced via WRF Model simulations. The estimates of the Doppler moments (reflectivity, mean Doppler velocity and spectrum width) are achieved via the pulse pair technique. The objective method for identification of MS-contaminated range-bins based purely on the reflectivity-derived variables is described, with most important one, cumulative integrated reflectivity, found to be 41 dBZ_int which serves as the threshold value for identification of radar range gates contaminated by MS. This is further demonstrated in a CloudSat case study with the threshold value for CloudSat is found to be 41.9 dBZ_int. The unfolding procedure of Doppler velocities will be presented. Then we will describe the

  11. Using Eye Tracking to Investigate Semantic and Spatial Representations of Scientific Diagrams During Text-Diagram Integration

    NASA Astrophysics Data System (ADS)

    Jian, Yu-Cin; Wu, Chao-Jung

    2015-02-01

    We investigated strategies used by readers when reading a science article with a diagram and assessed whether semantic and spatial representations were constructed while reading the diagram. Seventy-one undergraduate participants read a scientific article while tracking their eye movements and then completed a reading comprehension test. Our results showed that the text-diagram referencing strategy was commonly used. However, some readers adopted other reading strategies, such as reading the diagram or text first. We found all readers who had referred to the diagram spent roughly the same amount of time reading and performed equally well. However, some participants who ignored the diagram performed more poorly on questions that tested understanding of basic facts. This result indicates that dual coding theory may be a possible theory to explain the phenomenon. Eye movement patterns indicated that at least some readers had extracted semantic information of the scientific terms when first looking at the diagram. Readers who read the scientific terms on the diagram first tended to spend less time looking at the same terms in the text, which they read after. Besides, presented clear diagrams can help readers process both semantic and spatial information, thereby facilitating an overall understanding of the article. In addition, although text-first and diagram-first readers spent similar total reading time on the text and diagram parts of the article, respectively, text-first readers had significantly less number of saccades of text and diagram than diagram-first readers. This result might be explained as text-directed reading.

  12. Imaging the time-integrated cerebral metabolic activity with subcellular resolution through nanometer-scale detection of biosynthetic products deriving from (13)C-glucose.

    PubMed

    Takado, Yuhei; Knott, Graham; Humbel, Bruno M; Masoodi, Mojgan; Escrig, Stéphane; Meibom, Anders; Comment, Arnaud

    2015-11-01

    Glucose is the primary source of energy for the brain but also an important source of building blocks for proteins, lipids, and nucleic acids. Little is known about the use of glucose for biosynthesis in tissues at the cellular level. We demonstrate that local cerebral metabolic activity can be mapped in mouse brain tissue by quantitatively imaging the biosynthetic products deriving from [U-(13)C]glucose metabolism using a combination of in situ electron microscopy and secondary ion mass-spectroscopy (NanoSIMS). Images of the (13)C-label incorporated into cerebral ultrastructure with ca. 100 nm resolution allowed us to determine the timescale on which the metabolic products of glucose are incorporated into different cells, their sub-compartments and organelles. These were mapped in astrocytes and neurons in the different layers of the motor cortex. We see evidence for high metabolic activity in neurons via the nucleus (13)C enrichment. We observe that in all the major cell compartments, such as e.g. nucleus and Golgi apparatus, neurons incorporate substantially higher concentrations of (13)C-label than astrocytes. PMID:26409162

  13. Integrated real time studies to track all physical and chemical changes in polyimide film processing from casting to imidization

    NASA Astrophysics Data System (ADS)

    Unsal, Emre

    Physical and chemical changes during the complex multi-step thermal imidization reaction were investigated including all processing steps (solution casting, drying and imidization), using newly developed highly instrumented measurement systems. These instruments allowed us to observe the dynamic relationship between the bound solvent evaporation that causes relaxation and chain orientation during the imidization. Drying and imidization of PMDA-ODA solutions in NMP were investigated by a novel custom designed measurement system that tracks real time weight, thickness, surface temperature, in-plane and out-of-plane birefringence. At low temperature drying stage (T < 120°C), the weight and thickness reductions occurred rapidly as a result of solvent evaporation. All the parameters started leveling off while the out of plane birefringence steadily increased and reached a plateau at longer drying times. When the temperature was increased for imidization reaction (T=200°C), additional weight loss accompanied by temporary reduction of birefringence was observed due to evaporation of bound solvent as solvent molecules decomplexed from the polymer chains and plasticized the film. During the latter stage, out-of-plane birefringence rose rapidly as the polymer chains increasingly became oriented with their chain axes were preferentially oriented in the film plane. Throughout the whole process the in-plane birefringence remained zero. For the first time, these real time measurements allowed us to quantitatively show the dynamics between chain relaxation due to evaporation of the decomplexed solvent molecules, and orientation development due to decreased chain mobility caused by imidization reaction and increasing Tg for the PMDA-ODA/NMP solutions. In addition, the dynamics of this interplay was investigated by varying the processing conditions: initial casting thickness and drying temperature. Chemical conversion, bound solvent and chain orientation that take place during

  14. Integrated radiotherapy imaging system (IRIS): design considerations of tumour tracking with linac gantry-mounted diagnostic x-ray systems with flat-panel detectors

    NASA Astrophysics Data System (ADS)

    Berbeco, Ross I.; Jiang, Steve B.; Sharp, Gregory C.; Chen, George T. Y.; Mostafavi, Hassan; Shirato, Hiroki

    2004-01-01

    The design of an integrated radiotherapy imaging system (IRIS), consisting of gantry mounted diagnostic (kV) x-ray tubes and fast read-out flat-panel amorphous-silicon detectors, has been studied. The system is meant to be capable of three main functions: radiographs for three-dimensional (3D) patient set-up, cone-beam CT and real-time tumour/marker tracking. The goal of the current study is to determine whether one source/panel pair is sufficient for real-time tumour/marker tracking and, if two are needed, the optimal position of each relative to other components and the isocentre. A single gantry-mounted source/imager pair is certainly capable of the first two of the three functions listed above and may also be useful for the third, if combined with prior knowledge of the target's trajectory. This would be necessary because only motion in two dimensions is visible with a single imager/source system. However, with previously collected information about the trajectory, the third coordinate may be derived from the other two with sufficient accuracy to facilitate tracking. This deduction of the third coordinate can only be made if the 3D tumour/marker trajectory is consistent from fraction to fraction. The feasibility of tumour tracking with one source/imager pair has been theoretically examined here using measured lung marker trajectory data for seven patients from multiple treatment fractions. The patients' selection criteria include minimum mean amplitudes of the tumour motions greater than 1 cm peak-to-peak. The marker trajectory for each patient was modelled using the first fraction data. Then for the rest of the data, marker positions were derived from the imager projections at various gantry angles and compared with the measured tumour positions. Our results show that, due to the three dimensionality and irregular trajectory characteristics of tumour motion, on a fraction-to-fraction basis, a 'monoscopic' system (single source/imager) is inadequate for

  15. HSA: integrating multi-track Hi-C data for genome-scale reconstruction of 3D chromatin structure.

    PubMed

    Zou, Chenchen; Zhang, Yuping; Ouyang, Zhengqing

    2016-01-01

    Genome-wide 3C technologies (Hi-C) are being increasingly employed to study three-dimensional (3D) genome conformations. Existing computational approaches are unable to integrate accumulating data to facilitate studying 3D chromatin structure and function. We present HSA ( http://ouyanglab.jax.org/hsa/ ), a flexible tool that jointly analyzes multiple contact maps to infer 3D chromatin structure at the genome scale. HSA globally searches the latent structure underlying different cleavage footprints. Its robustness and accuracy outperform or rival existing tools on extensive simulations and orthogonal experiment validations. Applying HSA to recent in situ Hi-C data, we found the 3D chromatin structures are highly conserved across various human cell types. PMID:26936376

  16. [Etiology of cerebral palsy].

    PubMed

    Jaisle, F

    1996-01-01

    The "perinatal asphyxia" is regarded to be one of the causes of cerebral palsy, though in the very most of the children with cerebral palsy there is found no hypoxia during labour. It should be mentioned, that the definition of "perinatal" and "asphyxia" neither are unic nor concret. And also there is no correlation between nonreassuring fetal heart rate patterns and acidosis in fetal blood with the incidence of cerebral palsy. Numerous studies in pregnant animals failed in proving an acute intrapartal hypoxia to be the origin of the cerebral palsy. Myers (1975) describes four patterns of anatomic brain damage after different injuries. Only his so called oligo-acidotic hypoxia, which is protracted and lasts over a longer time is leading to brain injury, which can be regarded in analogy to the injury of children with cerebral palsy. Summarising the update publications about the causes of cerebral palsy and the studies in pregnant animals there is no evidence that hypoxia during labour may be the cause of cerebral palsy. There is a great probability of a pre(and post-)natal origin of brain injury (for instance a periventricular leucomalacia found after birth) which leads to cerebral palsy. Short after labour signs of a so called "asphyxia" may occur in addition to this preexisting injury and misrepresent the cause of cerebral palsy. Finally the prepartal injury may cause both: Cerebral palsy and hypoxia. PMID:9035826

  17. Double Take: Parallel Processing by the Cerebral Hemispheres Reduces Attentional Blink

    ERIC Educational Resources Information Center

    Scalf, Paige E.; Banich, Marie T.; Kramer, Arthur F.; Narechania, Kunjan; Simon, Clarissa D.

    2007-01-01

    Recent data have shown that parallel processing by the cerebral hemispheres can expand the capacity of visual working memory for spatial locations (J. F. Delvenne, 2005) and attentional tracking (G. A. Alvarez & P. Cavanagh, 2005). Evidence that parallel processing by the cerebral hemispheres can improve item identification has remained elusive.…

  18. Development of integrated protocols to track the deposition and impacts of metal contaminants in tidal riverine environments

    NASA Astrophysics Data System (ADS)

    Roe, Helen M.; Patterson, R. Timothy; Nasser, Nawaf; Edwards, Robin J.; Graham, Conor

    2016-04-01

    Tidally-influenced rivers are particularly vulnerable to the effects of metal contamination, yet are amongst the most complex fluvial environments in terms of their sediment deposition and transport patterns. We present the results of an interdisciplinary study that aims to elucidate the fluxes and deposition of metal contaminants in a tidally-influenced river system in Northern Ireland, with a view to developing protocols that will have wide applicability for the monitoring and assessment of metal contaminants in similar environments in other regions. We employ a novel methodology that combines ICPMS analysis of sediments, ITRAX-based core analysis and the examination a important group of shelled protozoans (foraminifera), which occur widely in tidal riverine environments, and which are highly sensitive to metal contamination. The responses shown by the group vary between species and with different levels of contaminant exposure. Some species, for example, show increased relative abundances in proximity to discharge sources, whilst others develop chamber deformities. Application of our integrated multiproxy approach to the analysis of surface sediment samples and cores provides a framework for assessing both the spatial and temporal patterns of metal deposition and the impact of contaminants on the biota. Modern sediment samples (n=90) were collected at varying distances from a point contamination source (a former industrial site) in different morpho-sedimentary settings. The impact of 25 measured variables on the modern foraminiferal faunas was considered, including 20 metals, pH, conductivity, elevation and particle size. Channel sediments in close proximity to the contamination source and with the highest levels of Fe, Cu, Zn, Mg and As, yielded the sparsest foraminiferal faunas (Shannon Diversity Index values 0-1.5), whilst the highest prevalence of foraminiferids showing chamber deformities were observed in channel edge and levée bank sites. Kernal density

  19. Hemiparesis post cerebral malaria

    PubMed Central

    Taiaa, Oumkaltoum; Amil, Touriya; Darbi, Abdelatif

    2015-01-01

    Cerebral malaria is one of the most serious complications in the Plasmodium falciparum infection. In endemic areas, the cerebral malaria interested mainly children. The occurrence in adults is very rare and most interested adult traveling in tropical zones. This case report describes a motor deficit post cerebral malaria in a young adult traveling in malaria endemic area. This complication has been reported especially in children and seems very rare in adults. PMID:25995798

  20. Integration for Airborne Dust Prediction Systems and Vegetation Phenology to Track Pollen for Asthma Alerts in Public Health Decision Support Systems

    NASA Technical Reports Server (NTRS)

    Luvall, J. C.; Sprigg, W. A.; Nickovic, S.; Huete, A.; Budge, A.; Flowers, L.

    2008-01-01

    The objective of the program is to assess the feasibility of combining a dust transport model with MODIS derived phenology to study pollen transport for integration with a public health decision support system. The use of pollen information has specifically be identified as a critical need by the New Mexico State Health department for inclusion in the Environmental Public Health Tracking (EPHT) program. Material and methods: Pollen can be transported great distances. Local observations of plan phenology may be consistent with the timing and source of pollen collected by pollen sampling instruments. The Dust REgional Atmospheric Model (DREAM) is an integrated modeling system designed to accurately describe the dust cycle in the atmosphere. The dust modules of the entire system incorporate the state of the art parameterization of all the major phases of the atmospheric dust life such as production, diffusion, advection, and removal. These modules also include effects of the particles size distribution on aerosol dispersion. The model was modified to use pollen sources instead of dust. Pollen release was estimated based on satellite-derived phenology of key plan species and vegetation communities. The MODIS surface reflectance product (MOD09) provided information on the start of the plant growing season, growth stage, and pollen release. The resulting deterministic model is useful for predicting and simulating pollen emission and downwind concentration to study details of phenology and meteorology and their dependencies. The proposed linkage in this project provided critical information on the location timing and modeled transport of pollen directly to the EPHT> This information is useful to support the centers for disease control and prevention (CDC)'s National EPHT and the state of New Mexico environmental public health decision support for asthma and allergies alerts.

  1. The Arctic Research Mapping Application (ARMAP) Partners with the Alaska Data Integration Working Group (ADIwg) to Develop an Interagency Web Service Standard for Sharing Project Tracking

    NASA Astrophysics Data System (ADS)

    Cody, R. P.; Kassin, A.; Graves Gaylord, A.; Manley, W. F.; Franco, J. C.; Dover, M.; Garcia-Lavigne, D.; Score, R.; Tweedie, C. E.

    2011-12-01

    The Arctic Research Mapping Application (ARMAP) has partnered with the Alaska Data Integration Working Group (ADIwg) to develop and implement an interagency standard for project tracking (who's doing what, when and where in the region) with RESTful (Respresentational State Transfer) web services. This standard is derived from the Federal Geographic Data Committee and International Standards Organization's XML-based metadata standard. It allows for free open access to high-level project information from various entities and government agencies. The standard has been utilized in the development and enhancement of the ARMAP 2D application (http://armap.org) which allows users to search for research projects by location, year, funding program, keyword, investigator, and discipline, among other variables. Key information about each project is displayed within the application with links to web pages that provide additional information. The ARMAP 2D application has been significantly enhanced to include support for multiple projections, improved base maps, additional reference data layers, and optimization for better performance. The additional functionality of this tool will increase awareness of projects funded by numerous entities in the Arctic, enhance coordination for logistics support, help identify geographic gaps in research efforts and potentially foster more collaboration amongst researchers working in the region.

  2. Cerebral Asymmetries and Reading Acquisition

    ERIC Educational Resources Information Center

    Pirozzolo, Francis J.

    1978-01-01

    Reviewed are historical developments regarding the concepts of cerebral localization, and analyzed are implications of current research on the role of the cerebral hemispheres in reading disorders. (CL)

  3. Derailing Tracking.

    ERIC Educational Resources Information Center

    Black, Susan

    1993-01-01

    Reviews recent research on student achievement, self-concept, and curriculum and instruction showing the ineffectiveness of tracking and ability grouping. Certain court rulings show that tracking violates the equal protection clause of the Fourteenth Amendment. Innovative alternatives include cooperative learning, mastery learning, peer tutoring,…

  4. Beyond Tracking.

    ERIC Educational Resources Information Center

    Bates, Percy; And Others

    1992-01-01

    On the surface, educational tracking may seem like a useful tool for allowing students to work at their own pace, and to avoid discouraging competition, but abuses of the tracking idea have arisen through biased placement practices that have denied equal access to education for minority students. The articles in this issue explore a number of…

  5. Adaptive Objectness for Object Tracking

    NASA Astrophysics Data System (ADS)

    Liang, Pengpeng; Pang, Yu; Liao, Chunyuan; Mei, Xue; Ling, Haibin

    2016-07-01

    Object tracking is a long standing problem in vision. While great efforts have been spent to improve tracking performance, a simple yet reliable prior knowledge is left unexploited: the target object in tracking must be an object other than non-object. The recently proposed and popularized objectness measure provides a natural way to model such prior in visual tracking. Thus motivated, in this paper we propose to adapt objectness for visual object tracking. Instead of directly applying an existing objectness measure that is generic and handles various objects and environments, we adapt it to be compatible to the specific tracking sequence and object. More specifically, we use the newly proposed BING objectness as the base, and then train an object-adaptive objectness for each tracking task. The training is implemented by using an adaptive support vector machine that integrates information from the specific tracking target into the BING measure. We emphasize that the benefit of the proposed adaptive objectness, named ADOBING, is generic. To show this, we combine ADOBING with seven top performed trackers in recent evaluations. We run the ADOBING-enhanced trackers with their base trackers on two popular benchmarks, the CVPR2013 benchmark (50 sequences) and the Princeton Tracking Benchmark (100 sequences). On both benchmarks, our methods not only consistently improve the base trackers, but also achieve the best known performances. Noting that the way we integrate objectness in visual tracking is generic and straightforward, we expect even more improvement by using tracker-specific objectness.

  6. Complementary and Alternative Therapies for Cerebral Palsy

    ERIC Educational Resources Information Center

    Liptak, Gregory S.

    2005-01-01

    The optimal practice of medicine includes integrating individual clinical expertise with the best available clinical evidence from systematic research. This article reviews nine treatment modalities used for children who have cerebral palsy (CP), including hyperbaric oxygen, the Adeli Suit, patterning, electrical stimulation, conductive education,…

  7. Cerebral Palsy--A Continuing Battle.

    ERIC Educational Resources Information Center

    Gullerud, Ruth A.

    1979-01-01

    A review of the changes in the treatment of and attitudes toward cerebral palsy in the last 30 years is presented. The author stresses the need for early diagnosis and evaluation, day care (especially respite care), counseling, transportation, special living arrangements, and integration of this population. (PHR)

  8. Solutions Network Formulation Report. Integration of OMI and TES Aerosol Products into the EPA Regional Planning Organizations' FASTNET Aerosol Tracking and Analysis Tool

    NASA Technical Reports Server (NTRS)

    Knowlton, Kelly; Andrews, Jane C.

    2006-01-01

    Every year, more than 280 million visitors tour our Nation s most treasured parks and wilderness areas. Unfortunately, many visitors are unable to see the spectacular vistas they expect because of white or brown haze in the air. Most of this haze is not natural; it is air pollution, carried by the wind often hundreds of miles from its origin. Some of the pollutants have been linked to serious health problems, such as asthma and other lung disorders, and even premature death. In addition, nitrates and sulfates contribute to acid rain formation, which contaminates rivers and lakes and erodes buildings and historical monuments. The U.S. Environmental Protection Agency RPOs (Regional Planning Organizations) have been tasked with monitoring and determining the nature and origin of haze in Class I scenic areas, and finding ways to reduce haze in order to improve visibility in these areas. The RPOs have developed an Internet-based air quality DST (Decision Support Tool) called FASTNET (Fast Aerosol Sensing Tools for Natural Event Tracking). While FASTNET incorporates a few satellite datasets, most of the data utilized by this DST comes from ground-based instrument networks. The problem is that in many areas the sensors are sparsely located, with long distances between them, causing difficulties in tracking haze over the United States, determining its source, and analyzing its content. Satellite data could help to fill in the data gaps and to supplement and verify ground-recorded air quality data. Although satellite data are now being used for air quality research applications, such data are not routinely used for environmental decision support, in part because of limited resources, difficulties with interdisciplinary data interpretation, and the need for advanced inter-agency partnerships. As a result, the validation and verification of satellite data for air quality operational system applications has been limited This candidate solution evaluates the usefulness of OMI

  9. Cerebral Palsy (CP) Quiz

    MedlinePlus

    ... Submit Button Past Emails CDC Features Pop Quiz: Cerebral Palsy Language: English Español (Spanish) Recommend on Facebook Tweet ... Sandy is the parent of a child with cerebral palsy and the Board President of Gio’s Garden , a ...

  10. Apraxia in deep cerebral lesions.

    PubMed Central

    Agostoni, E; Coletti, A; Orlando, G; Tredici, G

    1983-01-01

    In a series of 50 patients with cerebrovascular lesions (demonstrated with CT scan), seven patients had lesions located in the basal ganglia and/or thalamus. All these seven patients were apractic. Ideomotor apraxia was present in all patients; five also had constructional apraxia, and one had bucco-facial apraxia. None of the patients had utilisation apraxia. These observations indicated that apraxia is not only a "high cerebral (cortical) function", but may depend also on the integrity of subcortical circuits and structures. PMID:6619888

  11. MATERIAL TRACKING USING LANMAS

    SciTech Connect

    Armstrong, F.

    2010-06-07

    LANMAS is a transaction-based nuclear material accountability software product developed to replace outdated and legacy accountability systems throughout the DOE. The core underlying purpose of LANMAS is to track nuclear materials inventory and report transactions (movement, mixing, splitting, decay, etc.) to the Nuclear Materials Management and Safeguards System (NMMSS). While LANMAS performs those functions well, there are many additional functions provided by the software product. As a material is received onto a site or created at a site, its entire lifecycle can be tracked in LANMAS complete to its termination of safeguards. There are separate functions to track material movements between and within material balance areas (MBAs). The level of detail for movements within a MBA is configurable by each site and can be as high as a site designation or as detailed as building/room/rack/row/position. Functionality exists to track the processing of materials, either as individual items or by modeling a bulk process as an individual item to track inputs and outputs from the process. In cases where sites have specialized needs, the system is designed to be flexible so that site specific functionality can be integrated into the product. This paper will demonstrate how the software can be used to input material into an account and track it to its termination of safeguards.

  12. Training Guide to Cerebral Palsy Sports. Third Edition.

    ERIC Educational Resources Information Center

    Jones, Jeffery A., Ed.

    This official training manual of the United States Cerebral Palsy Athletic Association includes the latest coaching and training techniques specific to all sports in the national program. The book features guidelines for coaching over a dozen sports, including soccer, swimming, cycling, and track and field. It contains everything coaches,…

  13. Rover tracks

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Tracks made by the Sojourner rover are visible in this image, taken by one of the cameras aboard Sojourner on Sol 3. The tracks represent the rover maneuvering towards the rock dubbed 'Barnacle Bill.' The rover, having exited the lander via the rear ramp, first traveled towards the right portion of the image, and then moved forward towards the left where Barnacle Bill sits. The fact that the rover was making defined tracks indicates that the soil is made up of particles on a micron scale.

    Mars Pathfinder was developed and managed by the Jet Propulsion Laboratory (JPL) for the National Aeronautics and Space Administration.

  14. Integration of kerma-area product and cumulative air kerma determination into a skin dose tracking system for fluoroscopic imaging procedures

    NASA Astrophysics Data System (ADS)

    Vijayan, Sarath; Shankar, Alok; Rudin, Stephen; Bednarek, Daniel R.

    2016-03-01

    The skin dose tracking system (DTS) that we developed provides a color-coded mapping of the cumulative skin dose distribution on a 3D graphic of the patient during fluoroscopic procedures in real time. The DTS has now been modified to also calculate the kerma area product (KAP) and cumulative air kerma (CAK) for fluoroscopic interventions using data obtained in real-time from the digital bus on a Toshiba Infinix system. KAP is the integral of air kerma over the beam area and is typically measured with a large-area transmission ionization chamber incorporated into the collimator assembly. In this software, KAP is automatically determined for each x-ray pulse as the product of the air kerma/ mAs from a calibration file for the given kVp and beam filtration times the mAs per pulse times the length and width of the beam times a field nonuniformity correction factor. Field nonuniformity is primarily the result of the heel effect and the correction factor was determined from the beam profile measured using radio-chromic film. Dividing the KAP by the beam area at the interventional reference point provides the area averaged CAK. The KAP and CAK per x-ray pulse are summed after each pulse to obtain the total procedure values in real-time. The calculated KAP and CAK were compared to the values displayed by the fluoroscopy machine with excellent agreement. The DTS now is able to automatically calculate both KAP and CAK without the need for measurement by an add-on transmission ionization chamber.

  15. Tracking and understanding volcanic emissions through cross-disciplinary integration of field, textural, geochemical and geophysical data: A textural working group. (Invited)

    NASA Astrophysics Data System (ADS)

    gurioli, L.

    2013-12-01

    Relating magma ascent to eruption style using information preserved in pyroclastic deposits is a major challenge in modern volcanology. Because magma ascent and fragmentation are inaccessible to direct observation, one way to obtain quantitative information for conduit dynamics is through textural quantification of the sampled products (i.e., full definition of the rock vesicle and crystal properties). Many workers have shown that quantification of vesicle and crystal size distributions yields valuable insights into the processes that created the pyroclasts. However, the physical characteristics of individual pyroclasts must not be considered in isolation from information regarding: (i) the deposits from which they are taken; (ii) their chemistry; (iii) geophysical signatures of the related explosive events; and (iv) results from petrological and/or analogue experiments. As a result, attempts to understand eruption dynamics have increasingly involved the coupling of traditional field and sample-return analyses with geophysical measurements made synchronous with sample collection. In spite of this progress, we remain far from developing a definitive methods that allows us to sample, correlate and/or compare the multitude of parameters that can be measured at an actively building field deposits. As a result, no study has yet been able to correlate all derivable textural parameters with the full range of available multidisciplinary data. To discuss these issues, a working group met during 6-7 November 2012 at the Maison International of the Université Blaise Pascal (Clermont-Ferrand, France). The workshop was supported by the European Science Foundation and was held under the title: 'Tracking and understanding volcanic emissions through cross-disciplinary integration: A textural working group'. Our main objective was to gather an advisory group to define measurements, methods, formats and standards to be applied to integration of geophysical and physical

  16. Cerebral Autoregulation Real-Time Monitoring

    PubMed Central

    Tsalach, Adi; Ratner, Eliahu; Lokshin, Stas; Silman, Zmira; Breskin, Ilan; Budin, Nahum; Kamar, Moshe

    2016-01-01

    Cerebral autoregulation is a mechanism which maintains constant cerebral blood flow (CBF) despite changes in mean arterial pressure (MAP). Assessing whether this mechanism is intact or impaired and determining its boundaries is important in many clinical settings, where primary or secondary injuries to the brain may occur. Herein we describe the development of a new ultrasound tagged near infra red light monitor which tracks CBF trends, in parallel, it continuously measures blood pressure and correlates them to produce a real time autoregulation index. Its performance is validated in both in-vitro experiment and a pre-clinical case study. Results suggest that using such a tool, autoregulation boundaries as well as its impairment or functioning can be identified and assessed. It may therefore assist in individualized MAP management to ensure adequate organ perfusion and reduce the risk of postoperative complications, and might play an important role in patient care. PMID:27571474

  17. Mechanisms of Astrocyte-Mediated Cerebral Edema

    PubMed Central

    Stokum, Jesse A.; Kurland, David B.; Gerzanich, Volodymyr; Simard, J. Marc

    2014-01-01

    Cerebral edema formation stems from disruption of blood brain barrier (BBB) integrity and occurs after injury to the CNS. Due to the restrictive skull, relatively small increases in brain volume can translate into impaired tissue perfusion and brain herniation. In excess, cerebral edema can be gravely harmful. Astrocytes are key participants in cerebral edema by virtue of their relationship with the cerebral vasculature, their unique compliment of solute and water transport proteins, and their general role in brain volume homeostasis. Following the discovery of aquaporins, passive conduits of water flow, aquaporin 4 (AQP4) was identified as the predominant astrocyte water channel. Normally, AQP4 is highly enriched at perivascular endfeet, the outermost layer of the BBB, whereas after injury, AQP4 expression disseminates to the entire astrocytic plasmalemma, a phenomenon termed dysregulation. Arguably, the most important role of AQP4 is to rapidly neutralize osmotic gradients generated by ionic transporters. In pathological conditions, AQP4 is believed to be intimately involved in the formation and clearance of cerebral edema. In this review, we discuss aquaporin function and localization in the BBB during health and injury, and we examine post-injury ionic events that modulate AQP4- dependent edema formation. PMID:24996934

  18. Cerebral amyloid angiopathy

    MedlinePlus

    ... Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley's Neurology in Clinical Practice . 6th ed. Philadelphia, PA: Elsevier ... al. Course of cerebral amyloid angiopathy-related inflammation. Neurology. 2007;68:1411-1416. PMID: 17452586 www.ncbi. ...

  19. Rehabilitation in cerebral palsy.

    PubMed Central

    Molnar, G. E.

    1991-01-01

    Cerebral palsy is the most frequent physical disability of childhood onset. Over the past four decades, prevalence has remained remarkably constant at 2 to 3 per 1,000 live births in industrialized countries. In this article I concentrate on the rehabilitation and outcome of patients with cerebral palsy. The epidemiologic, pathogenetic, and diagnostic aspects are highlighted briefly as they pertain to the planning and implementation of the rehabilitation process. PMID:1866952

  20. Learning to track multiple targets.

    PubMed

    Liu, Xiao; Tao, Dacheng; Song, Mingli; Zhang, Luming; Bu, Jiajun; Chen, Chun

    2015-05-01

    Monocular multiple-object tracking is a fundamental yet under-addressed computer vision problem. In this paper, we propose a novel learning framework for tracking multiple objects by detection. First, instead of heuristically defining a tracking algorithm, we learn that a discriminative structure prediction model from labeled video data captures the interdependence of multiple influence factors. Given the joint targets state from the last time step and the observation at the current frame, the joint targets state at the current time step can then be inferred by maximizing the joint probability score. Second, our detection results benefit from tracking cues. The traditional detection algorithms need a nonmaximal suppression postprocessing to select a subset from the total detection responses as the final output and a large number of selection mistakes are induced, especially under a congested circumstance. Our method integrates both detection and tracking cues. This integration helps to decrease the postprocessing mistake risk and to improve performance in tracking. Finally, we formulate the entire model training into a convex optimization problem and estimate its parameters using the cutting plane optimization. Experiments show that our method performs effectively in a large variety of scenarios, including pedestrian tracking in crowd scenes and vehicle tracking in congested traffic. PMID:25051561

  1. Nanomedicine in cerebral palsy

    PubMed Central

    Balakrishnan, Bindu; Nance, Elizabeth; Johnston, Michael V; Kannan, Rangaramanujam; Kannan, Sujatha

    2013-01-01

    Cerebral palsy is a chronic childhood disorder that can have diverse etiologies. Injury to the developing brain that occurs either in utero or soon after birth can result in the motor, sensory, and cognitive deficits seen in cerebral palsy. Although the etiologies for cerebral palsy are variable, neuroinflammation plays a key role in the pathophysiology of the brain injury irrespective of the etiology. Currently, there is no effective cure for cerebral palsy. Nanomedicine offers a new frontier in the development of therapies for prevention and treatment of brain injury resulting in cerebral palsy. Nanomaterials such as dendrimers provide opportunities for the targeted delivery of multiple drugs that can mitigate several pathways involved in injury and can be delivered specifically to the cells that are responsible for neuroinflammation and injury. These materials also offer the opportunity to deliver agents that would promote repair and regeneration in the brain, resulting not only in attenuation of injury, but also enabling normal growth. In this review, the current advances in nanotechnology for treatment of brain injury are discussed with specific relevance to cerebral palsy. Future directions that would facilitate clinical translation in neonates and children are also addressed. PMID:24204146

  2. Rho kinase as a target for cerebral vascular disorders

    PubMed Central

    Bond, Lisa M; Sellers, James R; McKerracher, Lisa

    2015-01-01

    The development of novel pharmaceutical treatments for disorders of the cerebral vasculature is a serious unmet medical need. These vascular disorders are typified by a disruption in the delicate Rho signaling equilibrium within the blood vessel wall. In particular, Rho kinase overactivation in the smooth muscle and endothelial layers of the vessel wall results in cytoskeletal modifications that lead to reduced vascular integrity and abnormal vascular growth. Rho kinase is thus a promising target for the treatment of cerebral vascular disorders. Indeed, preclinical studies indicate that Rho kinase inhibition may reduce the formation/growth/rupture of both intracranial aneurysms and cerebral cavernous malformations. PMID:26062400

  3. [Negative symptoms and cerebral imaging].

    PubMed

    Kaladjian, A; Belzeaux, R; Adida, M; Azorin, J-M

    2015-12-01

    A number of neuroanatomical and neurofonctional abnormalities have been evidenced by cerebral imaging studies in patients suffering from schizophrenia. Nevertheless, those specifically associated with the negative symptoms of this disease are still insufficiently known. This work is a review of selected studies that have assessed the brain correlates of negative symptoms in schizophrenia. Approaches using structural imaging have highlighted reduction of gray matter density or cortical thickness associated with negative symptoms, which is rather sparsely distributed within the frontal and temporal regions, localized nevertheless more particularly in the frontal medial and orbitofrontal areas, as well as the amygdalo-hippocampic complex. These deficits are concurrent with a loss of integrity of the principal paths of white matter tracts between frontal and limbic regions. On the other hand, neurofonctional abnormalities associated with negative symptoms involve especially the frontal areas and limbic striatum. A disturbed functioning within the fronto-striatal loops, related to a striatal dopaminergic deficit, may represent a potential explanatory hypothesis of the negative symptoms of schizophrenia, as suggested by studies using Positron Emission Tomography on this topic or neuroimaging studies on the effects of antipsychotics. A better identification of the cerebral abnormalities associated with the negative dimension of schizophrenia, with regard to the lateralization of these abnormalities or to their changes during the course of the disease, could offer new therapeutic modalities for the treatment of this dimension which, until now, remains few responsive to conventional pharmacological treatments. PMID:26776387

  4. Vasospasm in Cerebral Inflammation

    PubMed Central

    Eisenhut, Michael

    2014-01-01

    All forms of cerebral inflammation as found in bacterial meningitis, cerebral malaria, brain injury, and subarachnoid haemorrhage have been associated with vasospasm of cerebral arteries and arterioles. Vasospasm has been associated with permanent neurological deficits and death in subarachnoid haemorrhage and bacterial meningitis. Increased levels of interleukin-1 may be involved in vasospasm through calcium dependent and independent activation of the myosin light chain kinase and release of the vasoconstrictor endothelin-1. Another key factor in the pathogenesis of cerebral arterial vasospasm may be the reduced bioavailability of the vasodilator nitric oxide. Therapeutic trials in vasospasm related to inflammation in subarachnoid haemorrhage in humans showed a reduction of vasospasm through calcium antagonists, endothelin receptor antagonists, statins, and plasminogen activators. Combination of therapeutic modalities addressing calcium dependent and independent vasospasm, the underlying inflammation, and depletion of nitric oxide simultaneously merit further study in all conditions with cerebral inflammation in double blind randomised placebo controlled trials. Auxiliary treatment with these agents may be able to reduce ischemic brain injury associated with neurological deficits and increased mortality. PMID:25610703

  5. Cerebral venous sinus thrombosis

    PubMed Central

    Allroggen, H.; Abbott, R.

    2000-01-01

    Cerebral venous sinus thrombosis is a challenging condition because of its variability of clinical symptoms and signs. It is very often unrecognised at initial presentation. All age groups can be affected. Large sinuses such as the superior sagittal sinus are most frequently involved. Extensive collateral circulation within the cerebral venous system allows for a significant degree of compensation in the early stages of thrombus formation. Systemic inflammatory diseases and inherited as well as acquired coagulation disorders are frequent causes, although in up to 30% of cases no underlying cause can be identified. The oral contraceptive pill appears to be an important additional risk factor. The spectrum of clinical presentations ranges from headache with papilloedema to focal deficit, seizures and coma. Magnetic resonance imaging with venography is the investigation of choice; computed tomography alone will miss a significant number of cases. It has now been conclusively shown that intravenous heparin is the first-line treatment for cerebral venous sinus thrombosis because of its efficacy, safety and feasability. Local thrombolysis may be indicated in cases of deterioration, despite adequate heparinisation. This should be followed by oral anticoagulation for 3-6 months. The prognosis of cerebral venous sinus thrombosis is generally favourable. A high index of clinical suspicion is needed to diagnose this uncommon condition so that appropriate treatment can be initiated.


Keywords: cerebral venous sinus thrombosis PMID:10622773

  6. Tracking subsystem test requirements survey

    NASA Technical Reports Server (NTRS)

    Orr, D. H.; Tatosian, C. G.; Bynum, M. C.; Zook, A. W.

    1975-01-01

    A survey of the test and checkout requirements of the tracking portion of the communications and tracking subsystem was performed to evaluate adequacy of planned tests and test requirement documents. Emphasis is placed on identifying test completeness, duplications, and omissions. Items that may save time, aid in testing, and present a more complete integrated test program are also noted. The results of this survey are summarized.

  7. The Age of Human Cerebral Cortex Neurons

    SciTech Connect

    Bhardwaj, R D; Curtis, M A; Spalding, K L; Buchholz, B A; Fink, D; Bjork-Eriksson, T; Nordborg, C; Gage, F H; Druid, H; Eriksson, P S; Frisen, J

    2006-04-06

    The traditional static view of the adult mammalian brain has been challenged by the realization of continuous generation of neurons from stem cells. Based mainly on studies in experimental animals, adult neurogenesis may contribute to recovery after brain insults and decreased neurogenesis has been implicated in the pathogenesis of neurological and psychiatric diseases in man. The extent of neurogenesis in the adult human brain has, however, been difficult to establish. We have taken advantage of the integration of {sup 14}C, generated by nuclear bomb tests during the Cold War, in DNA to establish the age of neurons in the major areas of the human cerebral cortex. Together with the analysis of the cortex from patients who received BrdU, which integrates in the DNA of dividing cells, our results demonstrate that whereas non-neuronal cells turn over, neurons in the human cerebral cortex are not generated postnatally at detectable levels, but are as old as the individual.

  8. Communications and tracking technology discipline

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert

    1990-01-01

    Viewgraphs on communications and tracking technology discipline for Space Station Freedom are presented. The objective is to develop devices, components, and analytical methods to enhance and enable technology to meet space station evolutionary requirements for multiple access (proximity) communications, space-to-ground communications, and tracking as it pertains to rendezvous and docking as well as potential orbital debris warning systems. Topics covered include: optical communications and tracking; monolithic microwave integrated circuit systems; traveling wave tube technology; advanced modulation and coding; and advanced automation.

  9. Doppler tracking

    NASA Astrophysics Data System (ADS)

    Thomas, Christopher Jacob

    This study addresses the development of a methodology using the Doppler Effect for high-resolution, short-range tracking of small projectiles and vehicles. Minimal impact on the design of the moving object is achieved by incorporating only a transmitter in it and using ground stations for all other components. This is particularly useful for tracking objects such as sports balls that have configurations and materials that are not conducive to housing onboard instrumentation. The methodology developed here uses four or more receivers to monitor a constant frequency signal emitted by the object. Efficient and accurate schemes for filtering the raw signals, determining the instantaneous frequencies, time synching the frequencies from each receiver, smoothing the synced frequencies, determining the relative velocity and radius of the object and solving the nonlinear system of equations for object position in three dimensions as a function of time are developed and described here.

  10. Neuroprotection after cerebral ischemia

    PubMed Central

    Namura, Shobu; Ooboshi, Hiroaki; Liu, Jialing; Yenari, Midori A.

    2013-01-01

    Cerebral ischemia, a focal or global insufficiency of blood flow to the brain, can arise through multiple mechanisms, including thrombosis and arterial hemorrhage. Ischemia is a major driver of stroke, one of the leading causes of morbidity and mortality worldwide. While the general etiology of cerebral ischemia and stroke has been known for some time, the conditions have only recently been considered treatable. This report describes current research in this field seeking to fully understand the pathomechanisms underlying stroke; to characterize the brain’s intrinsic injury, survival, and repair mechanisms; to identify putative drug targets as well as cell-based therapies; and to optimize the delivery of therapeutic agents to the damaged cerebral tissue. PMID:23488559

  11. The cerebral venous system and hypoxia.

    PubMed

    Wilson, Mark H; Imray, Christopher H E

    2016-01-15

    Most hypobaric hypoxia studies have focused on oxygen delivery and therefore cerebral blood inflow. Few have studied venous outflow. However, the volume of blood entering and leaving the skull (∼700 ml/min) is considerably greater than cerebrospinal fluid production (0.35 ml/min) or edema formation rates and slight imbalances of in- and outflow have considerable effects on intracranial pressure. This dynamic phenomenon is not necessarily appreciated in the currently taught static "Monro-Kellie" doctrine, which forms the basis of the "Tight-Fit" hypothesis thought to underlie high altitude headache, acute mountain sickness, and high altitude cerebral edema. Investigating both sides of the cerebral circulation was an integral part of the 2007 Xtreme Everest Expedition. The results of the relevant studies performed as part of and subsequent to this expedition are reviewed here. The evidence from recent studies suggests a relative venous outflow insufficiency is an early step in the pathogenesis of high altitude headache. Translation of knowledge gained from high altitude studies is important. Many patients in a critical care environment develop hypoxemia akin to that of high altitude exposure. An inability to drain the hypoxemic induced increase in cerebral blood flow could be an underappreciated regulatory mechanism of intracranial pressure. PMID:26294747

  12. Motion Tracking System

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Integrated Sensors, Inc. (ISI), under NASA contract, developed a sensor system for controlling robot vehicles. This technology would enable a robot supply vehicle to automatically dock with Earth-orbiting satellites or the International Space Station. During the docking phase the ISI-developed sensor must sense the satellite's relative motion, then spin so the robot vehicle can adjust its motion to align with the satellite and slowly close until docking is completed. ISI used the sensing/tracking technology as the basis of its OPAD system, which simultaneously tracks an object's movement in six degrees of freedom. Applications include human limb motion analysis, assembly line position analysis and auto crash dummy motion analysis. The NASA technology is also the basis for Motion Analysis Workstation software, a package to simplify the video motion analysis process.

  13. GPS Metric Tracking Unit

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As Global Positioning Satellite (GPS) applications become more prevalent for land- and air-based vehicles, GPS applications for space vehicles will also increase. The Applied Technology Directorate of Kennedy Space Center (KSC) has developed a lightweight, low-cost GPS Metric Tracking Unit (GMTU), the first of two steps in developing a lightweight, low-cost Space-Based Tracking and Command Subsystem (STACS) designed to meet Range Safety's link margin and latency requirements for vehicle command and telemetry data. The goals of STACS are to improve Range Safety operations and expand tracking capabilities for space vehicles. STACS will track the vehicle, receive commands, and send telemetry data through the space-based asset, which will dramatically reduce dependence on ground-based assets. The other step was the Low-Cost Tracking and Data Relay Satellite System (TDRSS) Transceiver (LCT2), developed by the Wallops Flight Facility (WFF), which allows the vehicle to communicate with a geosynchronous relay satellite. Although the GMTU and LCT2 were independently implemented and tested, the design collaboration of KSC and WFF engineers allowed GMTU and LCT2 to be integrated into one enclosure, leading to the final STACS. In operation, GMTU needs only a radio frequency (RF) input from a GPS antenna and outputs position and velocity data to the vehicle through a serial or pulse code modulation (PCM) interface. GMTU includes one commercial GPS receiver board and a custom board, the Command and Telemetry Processor (CTP) developed by KSC. The CTP design is based on a field-programmable gate array (FPGA) with embedded processors to support GPS functions.

  14. Tracking Virtual Trajectories

    NASA Technical Reports Server (NTRS)

    Stone, Leland S.; Beutter, Brent R.; Lorenceau, Jean D.; Null, Cynthia H. (Technical Monitor)

    1996-01-01

    Current models of smooth pursuit eye movements assume that it is largely driven by retinal image motion. We tested this hypothesis by measuring pursuit of elliptical motion (3.2s, 0.9 Hz, 1.4 deg x 1.6 deg, 4 randomly interleaved phases) of either a small spot ("real" motion) or of a line-figure diamond viewed through apertures such that only the motion of four isolated oblique line segments was visible ("virtual" motion). Each segment moved sinusoidally along a linear trajectory yet subjects perceived a diamond moving along an elliptical path behind the aperture. We found, as expected, that real motion produced accurate tracking (N = 2) with mean gain (over horizontal and vertical) of 0.9, mean phase of -6 deg (lag), mean relative phase (H vs V) of 90 +/- 8 deg (RMS error). Virtual motion behind an X-shaped aperture (N= 4 with one naive) yielded a mean gain of 0.7, mean phase of -11 deg, mean relative phase of 87 +/- 15 deg. We also measured pursuit with the X-shaped aperture using a higher segment luminance which prevents the segments from being grouped into a coherently moving diamond while keeping the motion otherwise identical. In this incoherent case, the same four subjects no longer showed consistent elliptical tracking (RMS error in relative phase rose to 60 deg) suggesting that perceptual coherence is critical. Furthermore, to rule out tracking of the centroid, we also used vertical apertures so that all segment motion was vertical (N = 3). This stimulus still produced elliptical tracking (mean relative phase of 84 +/- 19 deg), albeit with a lower gain (0.6). These data show that humans can track moving objects reasonably accurately even when the trajectory can only be derived by spatial integration of motion signals. Models that merely seek to minimize retinal or local stimulus motion cannot explain these results.

  15. Cerebral Folate Deficiency

    ERIC Educational Resources Information Center

    Gordon, Neil

    2009-01-01

    Cerebral folate deficiency (CFD) is associated with low levels of 5-methyltetrahydrofolate in the cerebrospinal fluid (CSF) with normal folate levels in the plasma and red blood cells. The onset of symptoms caused by the deficiency of folates in the brain is at around 4 to 6 months of age. This is followed by delayed development, with deceleration…

  16. Cerebral Palsy Litigation

    PubMed Central

    Sartwelle, Thomas P.

    2015-01-01

    The cardinal driver of cerebral palsy litigation is electronic fetal monitoring, which has continued unabated for 40 years. Electronic fetal monitoring, however, is based on 19th-century childbirth myths, a virtually nonexistent scientific foundation, and has a false positive rate exceeding 99%. It has not affected the incidence of cerebral palsy. Electronic fetal monitoring has, however, increased the cesarian section rate, with the expected increase in mortality and morbidity risks to mothers and babies alike. This article explains why electronic fetal monitoring remains endorsed as efficacious in the worlds’ labor rooms and courtrooms despite being such a feeble medical modality. It also reviews the reasons professional organizations have failed to condemn the use of electronic fetal monitoring in courtrooms. The failures of tort reform, special cerebral palsy courts, and damage limits to stem the escalating litigation are discussed. Finally, the authors propose using a currently available evidence rule—the Daubert doctrine that excludes “junk science” from the courtroom—as the beginning of the end to cerebral palsy litigation and electronic fetal monitoring’s 40-year masquerade as science. PMID:25183322

  17. Erythropoietin and cerebral vascular protection: role of nitric oxide.

    PubMed

    Santhanam, Anantha Vijay R; Katusic, Zvonimir S

    2006-11-01

    Cerebral vasospasm after subarachnoid hemorrhage (SAH) is a major clinical problem causing cerebral ischemia and infarction. The pathogenesis of vasospasm is related to a number of pathological processes including endothelial damage and alterations in vasomotor function leading to narrowing of arterial diameter and a subsequent decrease in cerebral blood flow. Discovery of the tissue protective effects of erythropoietin (EPO) stimulated the search for therapeutic application of EPO for the prevention and treatment of cerebrovascular disease. Recent studies have identified the role of EPO in vascular protection mediated by the preservation of endothelial cell integrity and stimulation of angiogenesis. In this review, we discuss the EPO-induced activation of endothelial nitric oxide (NO) synthase and its contribution to the prevention of cerebral vasospasm. PMID:17049112

  18. Cerebral White Matter

    PubMed Central

    Schmahmann, Jeremy D.; Smith, Eric E.; Eichler, Florian S.; Filley, Christopher M.

    2013-01-01

    Lesions of the cerebral white matter (WM) result in focal neurobehavioral syndromes, neuropsychiatric phenomena, and dementia. The cerebral WM contains fiber pathways that convey axons linking cerebral cortical areas with each other and with subcortical structures, facilitating the distributed neural circuits that subserve sensorimotor function, intellect, and emotion. Recent neuroanatomical investigations reveal that these neural circuits are topographically linked by five groupings of fiber tracts emanating from every neocortical area: (1) cortico-cortical association fibers; (2) corticostriatal fibers; (3) commissural fibers; and cortico-subcortical pathways to (4) thalamus and (5) pontocerebellar system, brain stem, and/or spinal cord. Lesions of association fibers prevent communication between cortical areas engaged in different domains of behavior. Lesions of subcortical structures or projection/striatal fibers disrupt the contribution of subcortical nodes to behavior. Disconnection syndromes thus result from lesions of the cerebral cortex, subcortical structures, and WM tracts that link the nodes that make up the distributed circuits. The nature and the severity of the clinical manifestations of WM lesions are determined, in large part, by the location of the pathology: discrete neurological and neuropsychiatric symptoms result from focal WM lesions, whereas cognitive impairment across multiple domains—WM dementia—occurs in the setting of diffuse WM disease. We present a detailed review of the conditions affecting WM that produce these neurobehavioral syndromes, and consider the pathophysiology, clinical effects, and broad significance of the effects of aging and vascular compromise on cerebral WM, in an attempt to help further the understanding, diagnosis, and treatment of these disorders. PMID:18990132

  19. Noninvasive measurement of cerebral oxygen saturation and cerebral phronetal function

    NASA Astrophysics Data System (ADS)

    Li, Shengli; Zhang, Aiyu; Xu, Min; Jin, Taiyi

    1998-08-01

    Using the Near-Infrared Spectroscopy (NIRS), the noninvasive measurement of cerebral oxygen concentration can be achieved in vivo based on the Lambert-Beer Law. In this paper, we discuss the possibility of studying higher brain functions through combining cerebral oxygen saturation and cerebral function measurement. Event-related experiments are introduced to measure the cerebral phronetal function. Time domain curves show sight differences among these experiment results. However, with the aid of DFT, experiment data of all five human volunteers show the frequency near 20 Hz or 40 Hz is evoked depending on the difficulty of the mental tasks. The results demonstrate the feasibility of cerebral functions study by means of cerebral oxygen saturation measurement analyzed in the frequency domain.

  20. Intraoperative cerebral blood flow imaging of rodents

    NASA Astrophysics Data System (ADS)

    Li, Hangdao; Li, Yao; Yuan, Lu; Wu, Caihong; Lu, Hongyang; Tong, Shanbao

    2014-09-01

    Intraoperative monitoring of cerebral blood flow (CBF) is of interest to neuroscience researchers, which offers the assessment of hemodynamic responses throughout the process of neurosurgery and provides an early biomarker for surgical guidance. However, intraoperative CBF imaging has been challenging due to animal's motion and position change during the surgery. In this paper, we presented a design of an operation bench integrated with laser speckle contrast imager which enables monitoring of the CBF intraoperatively. With a specially designed stereotaxic frame and imager, we were able to monitor the CBF changes in both hemispheres during the rodent surgery. The rotatable design of the operation plate and implementation of online image registration allow the technician to move the animal without disturbing the CBF imaging during surgery. The performance of the system was tested by middle cerebral artery occlusion model of rats.

  1. Respiration tracking in radiosurgery

    SciTech Connect

    Schweikard, Achim; Shiomi, Hiroya; Adler, John

    2004-10-01

    Respiratory motion is difficult to compensate for with conventional radiotherapy systems. An accurate tracking method for following the motion of the tumor is of considerable clinical relevance. We investigate methods to compensate for respiratory motion using robotic radiosurgery. In this system the therapeutic beam is moved by a robotic arm, and follows the moving target through a combination of infrared tracking and synchronized x-ray imaging. Infrared emitters are used to record the motion of the patient's skin surface. The position of internal gold fiducials is computed repeatedly during treatment, via x-ray image processing. We correlate the motion between external and internal markers. From this correlation model we infer the placement of the internal target during time intervals where no x-ray images are taken. Fifteen patients with lung tumors have recently been treated with a fully integrated system implementing this new method. The clinical trials confirm our hypothesis that internal motion and external motion are indeed correlated. In a preliminar study we have extended our work to tracking without implanted fiducials, based on algorithms for computing deformation motions and digitally reconstructed radiographs.

  2. Cerebral blood flow at high altitude.

    PubMed

    Ainslie, Philip N; Subudhi, Andrew W

    2014-06-01

    This brief review traces the last 50 years of research related to cerebral blood flow (CBF) in humans exposed to high altitude. The increase in CBF within the first 12 hours at high altitude and its return to near sea level values after 3-5 days of acclimatization was first documented with use of the Kety-Schmidt technique in 1964. The degree of change in CBF at high altitude is influenced by many variables, including arterial oxygen and carbon dioxide tensions, oxygen content, cerebral spinal fluid pH, and hematocrit, but can be collectively summarized in terms of the relative strengths of four key integrated reflexes: 1) hypoxic cerebral vasodilatation; 2) hypocapnic cerebral vasoconstriction; 3) hypoxic ventilatory response; and 4) hypercapnic ventilatory response. Understanding the mechanisms underlying these reflexes and their interactions with one another is critical to advance our understanding of global and regional CBF regulation. Whether high altitude populations exhibit cerebrovascular adaptations to chronic levels of hypoxia or if changes in CBF are related to the development of acute mountain sickness are currently unknown; yet overall, the integrated CBF response to high altitude appears to be sufficient to meet the brain's large and consistent demand for oxygen. This short review is organized as follows: An historical overview of the earliest CBF measurements collected at high altitude introduces a summary of reported CBF changes at altitude over the last 50 years in both lowlanders and high-altitude natives. The most tenable candidate mechanism(s) regulating CBF at altitude are summarized with a focus on available data in humans, and a role for these mechanisms in the pathophysiology of AMS is considered. Finally, suggestions for future directions are provided. PMID:24971767

  3. Genetics of Cerebral Vasospasm

    PubMed Central

    Ladner, Travis R.; Zuckerman, Scott L.; Mocco, J

    2013-01-01

    Cerebral vasospasm (CV) is a major source of morbidity and mortality in aneurysmal subarachnoid hemorrhage (aSAH). It is thought that an inflammatory cascade initiated by extravasated blood products precipitates CV, disrupting vascular smooth muscle cell function of major cerebral arteries, leading to vasoconstriction. Mechanisms of CV and modes of therapy are an active area of research. Understanding the genetic basis of CV holds promise for the recognition and treatment for this devastating neurovascular event. In our review, we summarize the most recent research involving key areas within the genetics and vasospasm discussion: (1) Prognostic role of genetics—risk stratification based on gene sequencing, biomarkers, and polymorphisms; (2) Signaling pathways—pinpointing key inflammatory molecules responsible for downstream cellular signaling and altering these mediators to provide therapeutic benefit; and (3) Gene therapy and gene delivery—using viral vectors or novel protein delivery methods to overexpress protective genes in the vasospasm cascade. PMID:23691311

  4. Phenylpropanolamine and cerebral hemorrhage

    SciTech Connect

    McDowell, J.R.; LeBlanc, H.J.

    1985-05-01

    Computerized tomography, carotid angiograms, and arteriography were used to diagnose several cases of cerebral hemorrhage following the use of phenylpropanolamine. The angiographic picture in one of the three cases was similar to that previously described in association with amphetamine abuse and pseudoephedrine overdose, both substances being chemically and pharmacologically similar to phenylpropanolamine. The study suggests that the arterial change responsible for symptoms may be due to spasm rather than arteriopathy. 14 references, 5 figures.

  5. Cerebral dysgenesis. An overview.

    PubMed

    Schaefer, G B; Sheth, R D; Bodensteiner, J B

    1994-11-01

    A significant portion of patients with neurodevelopmental abnormalities (mental retardation, learning disabilities, and so forth) have no definable cause for these problems. Mounting evidence suggests a substantial number of these idiopathic conditions have subtle abnormalities of brain development (cerebral dysgenesis) as the inherent pathophysiologic event. In this article the authors summarize normal and abnormal brain development, the diagnostic approach to idiopathic neurodevelopmental anomalies, and the new molecular genetic insights into the underlying causes of brain malformations. PMID:7845342

  6. What provides cerebral reserve?

    PubMed

    Staff, Roger T; Murray, Alison D; Deary, Ian J; Whalley, Lawrence J

    2004-05-01

    The cerebral reserve hypothesis is a heuristic concept used to explain apparent protection from the onset of cerebral disease and/or cognitive decline in old age. A significant obstacle when investigating the reserve hypothesis is the absence of baseline data with which to compare current cognitive status. We tested the influence of three hypothesized proxies of reserve (education, head size and occupational attainment [OCC]) in 92 volunteers born in 1921, whose cognitive function was measured at age 11 and 79 years, and who underwent brain MRI. The association between each proxy and old age cognitive function was tested, adjusting for variance contributed by childhood mental ability and detrimental age-related pathological changes measured using MRI. The results showed that education and OCC, but not total intracranial volume (TICV), contribute to cerebral reserve and help retain cognitive function in old age. Education was found to contribute between 5 and 6% of the variance found in old age memory function but was found to have no significant association with reasoning abilities. OCC was found to contribute around 5% of the variance found in old age memory function and between 6 and 8% of the variance found in old age reasoning abilities. We conclude that the intellectual challenges experienced during life, such as education and occupation, accumulate reserve and allow cognitive function to be maintained in old age. PMID:15047587

  7. [Insomnia and cerebral hypoperfusion].

    PubMed

    Káposzta, Zoltán; Rácz, Klára

    2007-11-18

    Insomnia is defined as difficulty with the initiation, maintenance, duration, or quality of sleep that results in the impairment of daytime functioning, despite adequate opportunity and circumstances for sleep. In most countries approximately every third inhabitant has insomnia. Insomnia can be classified as primary and secondary. The pathogenesis of primary insomnia is unknown, but available evidence suggests a state of hyperarousal. Insomnia secondary to other causes is more common than primary insomnia. Cerebral hypoperfusion can be the cause of insomnia in some cases. In such patients the cerebral blood flow should be improved using parenteral vascular therapy. If insomnia persists despite treatment, then therapy for primary insomnia should be instituted using benzodiazepine-receptor agonists such as Zolpidem, Zopiclone, or Zaleplon. In those cases Midazolam cannot be used for the treatment of insomnia due to its marked negative effect on cerebral blood flow. In Hungary there is a need to organize multidisciplinary Insomnia Clinics because insomnia is more than a disease, it is a public health problem in this century. PMID:17988972

  8. Cerebral oxygenation and hyperthermia

    PubMed Central

    Bain, Anthony R.; Morrison, Shawnda A.; Ainslie, Philip N.

    2014-01-01

    Hyperthermia is associated with marked reductions in cerebral blood flow (CBF). Increased distribution of cardiac output to the periphery, increases in alveolar ventilation and resultant hypocapnia each contribute to the fall in CBF during passive hyperthermia; however, their relative contribution remains a point of contention, and probably depends on the experimental condition (e.g., posture and degree of hyperthermia). The hyperthermia-induced hyperventilatory response reduces arterial CO2 pressure (PaCO2) causing cerebral vasoconstriction and subsequent reductions in flow. During supine passive hyperthermia, the majority of recent data indicate that reductions in PaCO2 may be the primary, if not sole, culprit for reduced CBF. On the other hand, during more dynamic conditions (e.g., hemorrhage or orthostatic challenges), an inability to appropriately decrease peripheral vascular conductance presents a condition whereby adequate cerebral perfusion pressure may be compromised secondary to reductions in systemic blood pressure. Although studies have reported maintenance of pre-frontal cortex oxygenation (assessed by near-infrared spectroscopy) during exercise and severe heat stress, the influence of cutaneous blood flow is known to contaminate this measure. This review discusses the governing mechanisms associated with changes in CBF and oxygenation during moderate to severe (i.e., 1.0°C to 2.0°C increase in body core temperature) levels of hyperthermia. Future research directions are provided. PMID:24624095

  9. Track Construction Manual.

    ERIC Educational Resources Information Center

    Banke, Ron; Di Gennaro, Guy; Ediger, Rick; Garner, Lanny; Hersom, Steve; Miller, Jack; Nemeth, Ron; Petrucelli, Jim; Sierks, Donna; Smith, Don; Swank, Kevin; West, Kevin

    This book establishes guidelines for the construction and maintenance of tracks by providing information for building new tracks or upgrading existing tracks. Subjects covered include running track planning and construction, physical layout, available surfaces, and maintenance. General track requirements and construction specifications are…

  10. On the Right Track.

    ERIC Educational Resources Information Center

    Bieber, Ed

    1983-01-01

    Suggests thinking of "tracks" as clues and using them as the focus of outdoor activities in the urban environment. Provides 24 examples of possible track activities, including: seeds on the ground (track of a nearby tree), litter (track of a litterbug), and peeling paint (track of weathering forces). (JN)

  11. The thermal history of the Karoo Moatize-Minjova Basin, Tete Province, Mozambique: An integrated vitrinite reflectance and apatite fission track thermochronology study

    NASA Astrophysics Data System (ADS)

    Fernandes, Paulo; Cogné, Nathan; Chew, David M.; Rodrigues, Bruno; Jorge, Raul C. G. S.; Marques, João; Jamal, Daud; Vasconcelos, Lopo

    2015-12-01

    The Moatize-Minjova Basin is a Karoo-aged rift basin located in the Tete Province of central Mozambique along the present-day Zambezi River valley. In this basin the Permian Moatize and Matinde formations consist of interbedded carbonaceous mudstones and sandstones with coal seams. The thermal history has been determined using rock samples from two coal exploration boreholes (ca. 500 m depth) to constrain the burial and exhumation history of the basin. Organic maturation levels were determined using vitrinite reflectance and spore fluorescence/colour. Ages and rates of tectonic uplift and denudation have been assessed by apatite fission track analysis. The thermal history was modelled by inverse modelling of the fission track and vitrinite reflectance data. The Moatize Formation attained a coal rank of bituminous coals with low to medium volatiles (1.3-1.7%Rr). Organic maturation levels increase in a linear fashion downhole in the two boreholes, indicating that burial was the main process controlling peak temperature maturation. Calculated palaeogeothermal gradients range from 59 °C/km to 40 °C/km. According to the models, peak burial temperatures were attained shortly (3-10 Ma) after deposition. Apatite fission track ages [146 to 84 Ma (Cretaceous)] are younger than the stratigraphic age. Thermal modelling indicates two episodes of cooling and exhumation: a first period of rapid cooling between 240 and 230 Ma (Middle - Upper Triassic boundary) implying 2500-3000 m of denudation; and a second period, also of rapid cooling, from 6 Ma (late Miocene) onwards implying 1000-1500 m of denudation. The first episode is related to the main compressional deformation event within the Cape Fold Belt in South Africa, which transferred stress northwards on pre-existing transtensional fault systems within the Karoo rift basins, causing tectonic inversion and uplift. During the Mesozoic and most of the Cenozoic the basin is characterized by very slow cooling. The second period

  12. A-Train Data Depot: Integrating, Visualizing, and Extracting Cloudsat, CALIPSO, MODIS, and AIRS Atmospheric Measurements Along the A-Train Tracks

    NASA Technical Reports Server (NTRS)

    Kempler, Steven; Stephens, Graeme; Winkler, Dave; Leptoukh, Greg; Reinke, Don; Smith, Peter

    2006-01-01

    The succession of US and international Earth observing satellites that follow each other, seconds to minutes apart, across the local afternoon equator crossing is called the ATrain. The A-Train consists of the following satellites, in order of equator crossing: OCO, EOS Aqua, CloudSat, CALIPSO, PARASOL, and EOS Aura. Flying in such formation increases the number of observations, validates observations, and enables coordination between science observations, resulting in a more complete virtual science platform (Kelly, 2000). The goal of this project is to create the first ever A-Train virtual data portal/center, the A-Train Data Depot (ATDD), to process, archive, access, visualize, analyze and correlate distributed atmosphere measurements from various A-Train instruments along A-Train tracks. The ATDD will enable the free movement of remotely located A-Train data so that they are combined to create a consolidated vertical view of the Earth's Atmosphere along the A-Train tracks. Once the infrastructure of the ATDD is in place, it will be easily evolved to serve data from all A-Train data measurements: one stop shopping. The innovative approach of analyzing and visualizing atmospheric profiles along the platforms track (i.e., time) will be accommodated by reusing the GSFC Atmospheric Composition Data and Information Services Center (ACDISC) visualization and analysis tool, GIOVANNI, existing data reduction tools, on-line archiving for fast data access, access to remote data without unnecessary data transfers, and data retrieval by users finding data desirable for further study. Initial measurements utilized include CALIPSO lidar backscatter, CloudSat radar reflectivity, clear air relative humidity, water vapor and temperature from AIRS, and cloud properties and aerosols from both MODIS. This will be foilowed by associated measurements from TVILS, =MI, HIRDLS, sad TES. Given the independent nature of instrumentlplatform development, the ATDD project has been met with

  13. What You Should Know about Cerebral Aneurysms

    MedlinePlus

    ... About Stroke What You Should Know About Cerebral Aneurysms Updated:Jun 13,2014 About Cerebral Aneurysms Diagnosis ... to view an animation What is a cerebral aneurysm? An aneurysm is a weak area in a ...

  14. Molecular pathophysiology of cerebral edema.

    PubMed

    Stokum, Jesse A; Gerzanich, Volodymyr; Simard, J Marc

    2016-03-01

    Advancements in molecular biology have led to a greater understanding of the individual proteins responsible for generating cerebral edema. In large part, the study of cerebral edema is the study of maladaptive ion transport. Following acute CNS injury, cells of the neurovascular unit, particularly brain endothelial cells and astrocytes, undergo a program of pre- and post-transcriptional changes in the activity of ion channels and transporters. These changes can result in maladaptive ion transport and the generation of abnormal osmotic forces that, ultimately, manifest as cerebral edema. This review discusses past models and current knowledge regarding the molecular and cellular pathophysiology of cerebral edema. PMID:26661240

  15. Molecular pathophysiology of cerebral edema

    PubMed Central

    Gerzanich, Volodymyr; Simard, J Marc

    2015-01-01

    Advancements in molecular biology have led to a greater understanding of the individual proteins responsible for generating cerebral edema. In large part, the study of cerebral edema is the study of maladaptive ion transport. Following acute CNS injury, cells of the neurovascular unit, particularly brain endothelial cells and astrocytes, undergo a program of pre- and post-transcriptional changes in the activity of ion channels and transporters. These changes can result in maladaptive ion transport and the generation of abnormal osmotic forces that, ultimately, manifest as cerebral edema. This review discusses past models and current knowledge regarding the molecular and cellular pathophysiology of cerebral edema. PMID:26661240

  16. The Integration of Geographical Information System and Remotely Sensed Data to Track and Predict the Migration Path of the Africanized Honey Bee

    NASA Technical Reports Server (NTRS)

    Ward, Charles; Bravo, Jessica; De Luna, Rosalia; Lopez, Gerardo; Pichardo, Itza; Trejo, Danny; Vargas, Gabriel

    1997-01-01

    One of the research groups at the Pan American Center for Earth and Environmental Studies (PACES) is researching the northward migration path of Africanized Honey Bees or often referred to in the popular press as killer bees. The goal of the Killer Bee Research Group (KBRG) is to set up a database in the form of a geographical information system, which will be used to track and predict the bees future migration path. Included in this paper is background information on geographical information systems, the SPANS Explorer software package which was used to implement the database, and Advanced Very High Resolution Radiometer data and how each of these is being incorporated in the research. With an accurate means of predicting future migration paths, the negative effects of the Africanized honey bees maybe reduced.

  17. Integration of Airborne Aerosol Prediction Systems and Vegetation Phenology to Track Pollen for Asthma Alerts in Public Health Decision Support Systems

    NASA Technical Reports Server (NTRS)

    Luvall, Jeffrey C.; Sprigg, William A.; Huete, Alfredo; Pejanovic, Goran; Nickovic, Slobodan; Krapfl, Heide; Budge, Amy; Zelicoff, Alan; VandeWater, Peter K.; Levetin, Estelle; Losleben, Mark; Weltzin, Jake

    2009-01-01

    The residual signal indicates that the pollen event may influence the seasonal signal to an extent that would allow detection, given accurate QA filtering and BRDF corrections. MODIS daily reflectances increased during the pollen season. The DREAM model (PREAM) was successfully modified for use with pollen and may provide 24-36 hour running pollen forecasts. Publicly available pollen forecasts are linked to general weather patterns and roughly-known species phenologies. These are too coarse for timely health interventions. PREAM addresses this key data gap so that targeting intervention measures can be determined temporally and geospatially. The New Mexico Department of Health (NMDOH) as part of its Environmental Public Health Tracking Network (EPHTN) would use PREAM a tool for alerting the public in advance of pollen bursts to intervene and reduce the health impact on asthma populations at risk.

  18. Neuroprotective effects of systemic cerebral endothelial cell transplantation in a rat model of cerebral ischemia

    PubMed Central

    Moon, Jong-Hyun; Na, Joo-Young; Lee, Min-Cheol; Choi, Kang-Ho; Lee, Jeong-Kil; Min, Jung-Joon; Kim, Kyung-Tae; Park, Jong-Tae; Park, Man-Seok; Kim, Hyung-Seok

    2016-01-01

    Human cerebral microvascular endothelial cell line (hCMEC)/D3 cells, which are from a stable clonal cell line of human immortalized cerebral endothelial cells, were intra-arterially transplanted through the common carotid artery in a rat model of photochemical-induced cerebral ischemia. Their therapeutic effects on infarct size, blood-brain barrier (BBB) breakdown, and outcome were examined. The hCMEC/D3 cells were genetically modified with the firefly luciferase gene for in vivo imaging post-transplantation. Transplanted hCMEC/D3 cells were identified in the infarcted brain by bioluminescence imaging at 1 day after transplantation. Compared with the control group, the hCMEC/D3-transplanted group showed reduced infarct size on day 3, reduced Evans blue dye leakage on day 1 indicating decreased BBB breakdown, and early recovery from Rotarod test neurological deficits. The hCMEC/D3-transplanted group also showed decreased levels of matrix metalloproteinase (MMP)-9, which were inversely correlated with TIMP-1 levels on post-transplantation days 1 and 3. The expression of tumor necrosis factor-α and interleukin-1β were markedly diminished in the hCMEC/D3-transplanted group compared with controls. The systemically transplanted cells selectively migrated and integrated into the ischemically lesioned area, which accelerated neurological recovery. This new cerebral endothelial cell-based therapy may hold promise for clinical trials in patients with ischemic stroke. PMID:27347342

  19. Neuroprotective effects of systemic cerebral endothelial cell transplantation in a rat model of cerebral ischemia.

    PubMed

    Moon, Jong-Hyun; Na, Joo-Young; Lee, Min-Cheol; Choi, Kang-Ho; Lee, Jeong-Kil; Min, Jung-Joon; Kim, Kyung-Tae; Park, Jong-Tae; Park, Man-Seok; Kim, Hyung-Seok

    2016-01-01

    Human cerebral microvascular endothelial cell line (hCMEC)/D3 cells, which are from a stable clonal cell line of human immortalized cerebral endothelial cells, were intra-arterially transplanted through the common carotid artery in a rat model of photochemical-induced cerebral ischemia. Their therapeutic effects on infarct size, blood-brain barrier (BBB) breakdown, and outcome were examined. The hCMEC/D3 cells were genetically modified with the firefly luciferase gene for in vivo imaging post-transplantation. Transplanted hCMEC/D3 cells were identified in the infarcted brain by bioluminescence imaging at 1 day after transplantation. Compared with the control group, the hCMEC/D3-transplanted group showed reduced infarct size on day 3, reduced Evans blue dye leakage on day 1 indicating decreased BBB breakdown, and early recovery from Rotarod test neurological deficits. The hCMEC/D3-transplanted group also showed decreased levels of matrix metalloproteinase (MMP)-9, which were inversely correlated with TIMP-1 levels on post-transplantation days 1 and 3. The expression of tumor necrosis factor-α and interleukin-1β were markedly diminished in the hCMEC/D3-transplanted group compared with controls. The systemically transplanted cells selectively migrated and integrated into the ischemically lesioned area, which accelerated neurological recovery. This new cerebral endothelial cell-based therapy may hold promise for clinical trials in patients with ischemic stroke. PMID:27347342

  20. The use of a tracking test battery in the quantitative evaluation of neurological function

    NASA Technical Reports Server (NTRS)

    Repa, B. S.

    1973-01-01

    A number of tracking tasks that have proven useful to control engineers and psychologists measuring skilled performance have been evaluated for clinical use. Normal subjects as well as patients with previous diagnoses of Parkinson's disease, multiple sclerosis, and cerebral palsy were used in the evaluation. The tests that were studied included step tracking, random tracking, and critical tracking. The results of the present experiments encourage the continued use of tracking tasks as assessment precedures in a clinical environment. They have proven to be reliable, valid, and sensitive measures of neurological function.

  1. Radio tracking system

    NASA Technical Reports Server (NTRS)

    Breidenthal, J. C.; Komarek, T. A.

    1982-01-01

    The principles and techniques of deep space radio tracking are described along with the uses of tracking data in navigation and radio science. Emphasis is placed on the measurement functions of radio tracking.

  2. Effects of Surgery and Proton Therapy on Cerebral White Matter of Craniopharyngioma Patients

    SciTech Connect

    Uh, Jinsoo; Merchant, Thomas E.; Li, Yimei; Li, Xingyu; Sabin, Noah D.; Indelicato, Daniel J.; Ogg, Robert J.; Boop, Frederick A.; Jane, John A.; Hua, Chiaho

    2015-09-01

    Purpose: The purpose of this study was to determine radiation dose effect on the structural integrity of cerebral white matter in craniopharyngioma patients receiving surgery and proton therapy. Methods and Materials: Fifty-one patients (2.1-19.3 years of age) with craniopharyngioma underwent surgery and proton therapy in a prospective therapeutic trial. Anatomical magnetic resonance images acquired after surgery but before proton therapy were inspected to identify white matter structures intersected by surgical corridors and catheter tracks. Longitudinal diffusion tensor imaging (DTI) was performed to measure microstructural integrity changes in cerebral white matter. Fractional anisotropy (FA) derived from DTI was statistically analyzed for 51 atlas-based white matter structures of the brain to determine radiation dose effect. FA in surgery-affected regions in the corpus callosum was compared to that in its intact counterpart to determine whether surgical defects affect radiation dose effect. Results: Surgical defects were seen most frequently in the corpus callosum because of transcallosal resection of tumors and insertion of ventricular or cyst catheters. Longitudinal DTI data indicated reductions in FA 3 months after therapy, which was followed by a recovery in most white matter structures. A greater FA reduction was correlated with a higher radiation dose in 20 white matter structures, indicating a radiation dose effect. The average FA in the surgery-affected regions before proton therapy was smaller (P=.0001) than that in their non–surgery-affected counterparts with more intensified subsequent reduction of FA (P=.0083) after therapy, suggesting that surgery accentuated the radiation dose effect. Conclusions: DTI data suggest that mild radiation dose effects occur in patients with craniopharyngioma receiving surgery and proton therapy. Surgical defects present at the time of proton therapy appear to accentuate the radiation dose effect longitudinally

  3. Impaired cerebrovascular hemodynamics are associated with cerebral white matter damage

    PubMed Central

    Purkayastha, Sushmita; Fadar, Otite; Mehregan, Aujan; Salat, David H; Moscufo, Nicola; Meier, Dominik S; Guttmann, Charles RG; Fisher, Naomi DL; Lipsitz, Lewis A; Sorond, Farzaneh A

    2014-01-01

    White matter hyperintensities (WMH) in elderly individuals with vascular diseases are presumed to be due to ischemic small vessel diseases; however, their etiology is unknown. We examined the cross-sectional relationship between cerebrovascular hemodynamics and white matter structural integrity in elderly individuals with vascular risk factors. White matter hyperintensity volumes, fractional anisotropy (FA), and mean diffusivity (MD) were obtained from MRI in 48 subjects (75±7years). Pulsatility index (PI) and dynamic cerebral autoregulation (dCA) was assessed using transcranial Doppler ultrasound of the middle cerebral artery. Dynamic cerebral autoregulation was calculated from transfer function analysis (phase and gain) of spontaneous blood pressure and flow velocity oscillations in the low (LF, 0.03 to 0.15 Hz) and high (HF, 0.16 to 0.5 Hz) frequency ranges. Higher PI was associated with greater WMH (P<0.005). Higher phase across all frequency ranges was associated with greater FA and lower MD (P<0.005). Lower gain was associated with higher FA in the LF range (P=0.001). These relationships between phase and FA were significant in the territories limited to the middle cerebral artery as well as across the entire brain. Our results show a strong relationship between impaired cerebrovascular hemodynamics (PI and dCA) and loss of cerebral white matter structural integrity (WMH and DTI metrics) in elderly individuals. PMID:24129749

  4. Oligodendrogenesis after cerebral ischemia

    PubMed Central

    Zhang, Ruilan; Chopp, Michael; Zhang, Zheng Gang

    2013-01-01

    Neural stem cells in the subventricular zone (SVZ) of the lateral ventricle of adult rodent brain generate oligodendrocyte progenitor cells (OPCs) that disperse throughout the corpus callosum and striatum where some of OPCs differentiate into mature oligodendrocytes. Studies in animal models of stroke demonstrate that cerebral ischemia induces oligodendrogenesis during brain repair processes. This article will review evidence of stroke-induced proliferation and differentiation of OPCs that are either resident in white matter or are derived from SVZ neural progenitor cells and of therapies that amplify endogenous oligodendrogenesis in ischemic brain. PMID:24194700

  5. Hemodynamics of Cerebral Aneurysms

    PubMed Central

    Sforza, Daniel M.; Putman, Christopher M.; Cebral, Juan Raul

    2009-01-01

    The initiation and progression of cerebral aneurysms are degenerative processes of the arterial wall driven by a complex interaction of biological and hemodynamic factors. Endothelial cells on the artery wall respond physiologically to blood-flow patterns. In normal conditions, these responses are associated with nonpathological tissue remodeling and adaptation. The combination of abnormal blood patterns and genetics predisposition could lead to the pathological formation of aneurysms. Here, we review recent progress on the basic mechanisms of aneurysm formation and evolution, with a focus on the role of hemodynamic patterns. PMID:19784385

  6. An intelligent multi-target tracking system

    NASA Astrophysics Data System (ADS)

    Heyerdahl, E.

    1987-07-01

    An implementation of a general tracking system, integrating the target acquisition and tracking subsystems, was developed. It is based on image analysis and extensive use of models. The system permits improvements compared to in-service trackers in the sense that it enables multi-target tracking, automatic acquisition also during tracking and tracking through obscurations. The system is an implementation of a general tracking system. This system produces alternative estimates of a target and projects the corresponding objects into the image plane. To do this estimates of the projecting function are used. The different projections are synthesized through a thresholding process. The implemented system uses parallel Kalman filters to produce the object estimates and estimates the sensor position through a model of sensor dynamics and measurements of sensor angle velocity. Results, produced by the implemented system from IR imagery of a moving target in field are presented.

  7. Detection and Tracking of Dual-Labeled HIV Particles Using Wide-Field Live Cell Imaging to Follow Viral Core Integrity.

    PubMed

    Mamede, João I; Hope, Thomas J

    2016-01-01

    Live cell imaging is a valuable technique that allows the characterization of the dynamic processes of the HIV-1 life cycle. Here, we present a method of production and imaging of dual-labeled HIV viral particles that allows the visualization of two events. Varying release of the intravirion fluid phase marker reveals virion fusion and the loss of the integrity of HIV viral cores with the use of live wide-field fluorescent microscopy. PMID:26714704

  8. Cerebral pathology post heart transplantation.

    PubMed

    Peteghem, S Van; Pauw, M De

    2015-04-01

    Cerebral pathology is frequently encountered post heart transplantation with a cumulative incidence of about 80% after 15 years. A broad spectrum of disease entities is reported, from minor abnormalities to life-threatening diseases. Although cerebral infections and malignancies are rare in this patient population, they have a high mortality rate. Since 1991, 171 orthotopic heart transplantations were performed at the Ghent University Hospital with a 10-year survival rate of 75%. Severe cerebral complications occurred in 10 patients, with epilepsy in 2 patients, cerebrovascular accidents in 4 patients, cerebral infections in 3 patients and a cerebral malignancy in 1 patient, resulting in a fatal outcome in 7 patients. We present four of these cases. PMID:25292206

  9. Time-sharing visual and auditory tracking tasks

    NASA Technical Reports Server (NTRS)

    Tsang, Pamela S.; Vidulich, Michael A.

    1987-01-01

    An experiment is described which examined the benefits of distributing the input demands of two tracking tasks as a function of task integrality. Visual and auditory compensatory tracking tasks were utilized. Results indicate that presenting the two tracking signals in two input modalities did not improve time-sharing efficiency. This was attributed to the difficulty insensitivity phenomenon.

  10. Cerebral cartography and connectomics

    PubMed Central

    Sporns, Olaf

    2015-01-01

    Cerebral cartography and connectomics pursue similar goals in attempting to create maps that can inform our understanding of the structural and functional organization of the cortex. Connectome maps explicitly aim at representing the brain as a complex network, a collection of nodes and their interconnecting edges. This article reflects on some of the challenges that currently arise in the intersection of cerebral cartography and connectomics. Principal challenges concern the temporal dynamics of functional brain connectivity, the definition of areal parcellations and their hierarchical organization into large-scale networks, the extension of whole-brain connectivity to cellular-scale networks, and the mapping of structure/function relations in empirical recordings and computational models. Successfully addressing these challenges will require extensions of methods and tools from network science to the mapping and analysis of human brain connectivity data. The emerging view that the brain is more than a collection of areas, but is fundamentally operating as a complex networked system, will continue to drive the creation of ever more detailed and multi-modal network maps as tools for on-going exploration and discovery in human connectomics. PMID:25823870

  11. Cerebral sinus venous thrombosis

    PubMed Central

    Alvis-Miranda, Hernando Raphael; Milena Castellar-Leones, Sandra; Alcala-Cerra, Gabriel; Rafael Moscote-Salazar, Luis

    2013-01-01

    Cerebral sinus venous thrombosis (CSVT) is a rare phenomenon that can be seen with some frequency in young patients. CSVT is a multifactorial condition with gender-related specific causes, with a wide clinical presentation, the leading causes differ between developed and developing countries, converting CSVT in a condition characterized by a highly variable clinical spectra, difficult diagnosis, variable etiologies and prognosis that requires fine medical skills and a high suspicious index. Patients who presents with CSVT should underwent to CT-scan venography (CVT) and to the proper inquiry of the generating cause. This disease can affect the cerebral venous drainage and related anatomical structure. The symptoms may appear in relation to increased intracranial pressure imitating a pseudotumorcerebri. Prognosis depends on the early detection. Correcting the cause, generally the complications can be prevented. Mortality trends have diminished, and with the new technologies, surely it will continue. This work aims to review current knowledge about CSVT including its pathogenesis, etiology, clinical manifestations, diagnosis, and treatment. PMID:24347950

  12. Cerebral sinus venous thrombosis.

    PubMed

    Alvis-Miranda, Hernando Raphael; Milena Castellar-Leones, Sandra; Alcala-Cerra, Gabriel; Rafael Moscote-Salazar, Luis

    2013-10-01

    Cerebral sinus venous thrombosis (CSVT) is a rare phenomenon that can be seen with some frequency in young patients. CSVT is a multifactorial condition with gender-related specific causes, with a wide clinical presentation, the leading causes differ between developed and developing countries, converting CSVT in a condition characterized by a highly variable clinical spectra, difficult diagnosis, variable etiologies and prognosis that requires fine medical skills and a high suspicious index. Patients who presents with CSVT should underwent to CT-scan venography (CVT) and to the proper inquiry of the generating cause. This disease can affect the cerebral venous drainage and related anatomical structure. The symptoms may appear in relation to increased intracranial pressure imitating a pseudotumorcerebri. Prognosis depends on the early detection. Correcting the cause, generally the complications can be prevented. Mortality trends have diminished, and with the new technologies, surely it will continue. This work aims to review current knowledge about CSVT including its pathogenesis, etiology, clinical manifestations, diagnosis, and treatment. PMID:24347950

  13. [Noradrenaline and cerebral aging].

    PubMed

    Jouvet, M; Albarede, J L; Lubin, S; Meyrignac, C

    1991-01-01

    The central functions of norepinephrine (NE) are a recent discovery: regulation of alertness and of the wakefulness-sleep cycle, maintenance of attention, memory and learning, cerebral plasticity and neuro-protection. The anatomical, histological, biochemical and physiological properties of the central noradrenergic system: extreme capacity for ramification and arborization; slow conduction, non-myelinized axons with extrasynaptic varicosities producing and releasing NE; frequency of co-transmission phenomena, and; neuromodulation with fiber effect responsible for improvement in the signal over background noise ratio and selection of significant stimuli form a true interface between the outside world and the central nervous system, notably for the neocortex in the context of the cognitive treatment of information. This central noradrenergic system is involved in the neurophysiology and the clinical features of cerebral aging (ideation-motor and cognitive function slowing down, loss of behavioral adjustment), neuro-degenerative disorders (SDAT, Parkinson's disease), certain aspects of depression and less obvious conditions (head injuries, sequelae of cerebrovascular accidents, sub-cortical dementia). The recent development of medications improving alertness (adrafinil, modafinil) with a pure central action and specifically noradrenergic, may contribute to an improvement in these multifactorial disorders. PMID:1864252

  14. Solar tracking system

    DOEpatents

    Okandan, Murat; Nielson, Gregory N.

    2016-07-12

    Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

  15. Modelling cerebral blood oxygenation using Monte Carlo XYZ-PA

    NASA Astrophysics Data System (ADS)

    Zam, Azhar; Jacques, Steven L.; Alexandrov, Sergey; Li, Youzhi; Leahy, Martin J.

    2013-02-01

    Continuous monitoring of cerebral blood oxygenation is critically important for the management of many lifethreatening conditions. Non-invasive monitoring of cerebral blood oxygenation with a photoacoustic technique offers advantages over current invasive and non-invasive methods. We introduce a Monte Carlo XYZ-PA to model the energy deposition in 3D and the time-resolved pressures and velocity potential based on the energy absorbed by the biological tissue. This paper outlines the benefits of using Monte Carlo XYZ-PA for optimization of photoacoustic measurement and imaging. To the best of our knowledge this is the first fully integrated tool for photoacoustic modelling.

  16. Cerebral blood flow velocity in two patients with neonatal cerebral infarction.

    PubMed

    Nishimaki, S; Seki, K; Yokota, S

    2001-04-01

    Cerebral blood flow velocity was measured in the middle cerebral artery of two patients who exhibited unilateral neonatal cerebral infarction during the neonatal period. Doppler studies demonstrated increases in cerebral blood flow velocity but decreases in the resistance index on the affected side of the middle cerebral artery in the neonate who developed hemiplegia with cystic encephalomalacia, although the neonate with normal neurologic outcome exhibited symmetric cerebral blood flow velocity and resistance index. The asymmetry in cerebral blood flow velocity measurements of both middle cerebral arteries may be useful to evaluate the severity of brain damage and predict the neurodevelopmental prognosis of unilateral neonatal cerebral infarction. PMID:11377112

  17. NORAD satellite tracking

    NASA Technical Reports Server (NTRS)

    Liu, Joseph J. F.

    1987-01-01

    NORAD routinely tracks about 6000 orbiting objects. During the last 30 days of orbital time, prior to reentry, special perturbations are used in the orbital update procedure. Besides routine orbit determination, NORAD does special tasks such as predicting satellite orbit conjunctions within 20 km, ephimerides of weather satellites, satellite decay predictions and other studies. Since their mission is operational, they do not store the data from their analyses. The ballistic coefficient is not known for most of the orbiting objects. If a ballistic coefficient were derived that was consistent with one density model, it might give erroneous results if used with a different density model. Given the ballistic coefficient, density values could, in principle, be obtained from their tracking data. The densities would represent an integrated mean over the orbital path near perigee. They would be model dependent and would not necessarily represent the real density. In summary, the primary need is for reliable forecasts of solar flux (F10.7) and geomagnetic activity (Ap) in the 1 to 4 week time scale. Forecasts over longer time spans would also be useful for special projects.

  18. Mode S baseline radar tracking

    NASA Astrophysics Data System (ADS)

    Mancus, E. F.; Baker, L. H.

    1982-11-01

    The baseline performance characteristics of the moving target detector (MTD) and radar data acquisition system (RDAS) as an integral part of the Mode S sensor, were determined. The MTD and RDAS were separately evaluated to determine their capability to provide radar data suitable for utilization by the Mode S sensor and automated radar terminal system (ARTS). The design modifications made to the Mode S sensor to provide the capability of interfacing to either an MTD or RDAS were evaluated to determine if they were in compliance with the Federal Aviation Administration engineering requirement, FAA-ER-240-26. Radar baseline technical performance data was provided to characterize the MTD, RDAS, Mode S, and ARTS. The minimum radar tracking requirements are studied to determine if they are adequate to provide reliable radar track data to an air traffic control facility. It was concluded that the Mode S sensor, when integrated with an MTD-2 radar digitizer, can provide reliable primary radar track data to the ARTS III system for automated radar track acquisition.

  19. Is Vasomotion in Cerebral Arteries Impaired in Alzheimer's Disease?

    PubMed

    Di Marco, Luigi Yuri; Farkas, Eszter; Martin, Chris; Venneri, Annalena; Frangi, Alejandro F

    2015-01-01

    A substantial body of evidence supports the hypothesis of a vascular component in the pathogenesis of Alzheimer's disease (AD). Cerebral hypoperfusion and blood-brain barrier dysfunction have been indicated as key elements of this pathway. Cerebral amyloid angiopathy (CAA) is a cerebrovascular disorder, frequent in AD, characterized by the accumulation of amyloid-β (Aβ) peptide in cerebral blood vessel walls. CAA is associated with loss of vascular integrity, resulting in impaired regulation of cerebral circulation, and increased susceptibility to cerebral ischemia, microhemorrhages, and white matter damage. Vasomotion- the spontaneous rhythmic modulation of arterial diameter, typically observed in arteries/arterioles in various vascular beds including the brain- is thought to participate in tissue perfusion and oxygen delivery regulation. Vasomotion is impaired in adverse conditions such as hypoperfusion and hypoxia. The perivascular and glymphatic pathways of Aβ clearance are thought to be driven by the systolic pulse. Vasomotion produces diameter changes of comparable amplitude, however at lower rates, and could contribute to these mechanisms of Aβ clearance. In spite of potential clinical interest, studies addressing cerebral vasomotion in the context of AD/CAA are limited. This study reviews the current literature on vasomotion, and hypothesizes potential paths implicating impaired cerebral vasomotion in AD/CAA. Aβ and oxidative stress cause vascular tone dysregulation through direct effects on vascular cells, and indirect effects mediated by impaired neurovascular coupling. Vascular tone dysregulation is further aggravated by cholinergic deficit and results in depressed cerebrovascular reactivity and (possibly) impaired vasomotion, aggravating regional hypoperfusion and promoting further Aβ and oxidative stress accumulation. PMID:25720414

  20. A Motion Tracking and Sensor Fusion Module for Medical Simulation.

    PubMed

    Shen, Yunhe; Wu, Fan; Tseng, Kuo-Shih; Ye, Ding; Raymond, John; Konety, Badrinath; Sweet, Robert

    2016-01-01

    Here we introduce a motion tracking or navigation module for medical simulation systems. Our main contribution is a sensor fusion method for proximity or distance sensors integrated with inertial measurement unit (IMU). Since IMU rotation tracking has been widely studied, we focus on the position or trajectory tracking of the instrument moving freely within a given boundary. In our experiments, we have found that this module reliably tracks instrument motion. PMID:27046606

  1. Integration of altitude and airspeed information into a primary flight display via moving-tape formats: Evaluation during random tracking task

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Nataupsky, Mark; Steinmetz, George G.

    1987-01-01

    A ground-based aircraft simulation study was conducted to determine the effects on pilot preference and performance of integrating airspeed and altitude information into an advanced electronic primary flight display via moving-tape (linear moving scale) formats. Several key issues relating to the implementation of moving-tape formats were examined in this study: tape centering, tape orientation, and trend information. The factor of centering refers to whether the tape was centered about the actual airspeed or altitude or about some other defined reference value. Tape orientation refers to whether the represented values are arranged in descending or ascending order. Two pilots participated in this study, with each performing 32 runs along seemingly random, previously unknown flight profiles. The data taken, analyzed, and presented consisted of path performance parameters, pilot-control inputs, and electrical brain response measurements.

  2. TrackEye tracking algorithm characterization

    NASA Astrophysics Data System (ADS)

    Valley, Michael T.; Shields, Robert W.; Reed, Jack M.

    2004-10-01

    TrackEye is a film digitization and target tracking system that offers the potential for quantitatively measuring the dynamic state variables (e.g., absolute and relative position, orientation, linear and angular velocity/acceleration, spin rate, trajectory, angle of attack, etc.) for moving objects using captured single or dual view image sequences. At the heart of the system is a set of tracking algorithms that automatically find and quantify the location of user selected image details such as natural test article features or passive fiducials that have been applied to cooperative test articles. This image position data is converted into real world coordinates and rates with user specified information such as the image scale and frame rate. Though tracking methods such as correlation algorithms are typically robust by nature, the accuracy and suitability of each TrackEye tracking algorithm is in general unknown even under good imaging conditions. The challenges of optimal algorithm selection and algorithm performance/measurement uncertainty are even more significant for long range tracking of high-speed targets where temporally varying atmospheric effects degrade the imagery. This paper will present the preliminary results from a controlled test sequence used to characterize the performance of the TrackEye tracking algorithm suite.

  3. TrackEye tracking algorithm characterization.

    SciTech Connect

    Reed, Jack W.; Shields, Rob W; Valley, Michael T.

    2004-08-01

    TrackEye is a film digitization and target tracking system that offers the potential for quantitatively measuring the dynamic state variables (e.g., absolute and relative position, orientation, linear and angular velocity/acceleration, spin rate, trajectory, angle of attack, etc.) for moving objects using captured single or dual view image sequences. At the heart of the system is a set of tracking algorithms that automatically find and quantify the location of user selected image details such as natural test article features or passive fiducials that have been applied to cooperative test articles. This image position data is converted into real world coordinates and rates with user specified information such as the image scale and frame rate. Though tracking methods such as correlation algorithms are typically robust by nature, the accuracy and suitability of each TrackEye tracking algorithm is in general unknown even under good imaging conditions. The challenges of optimal algorithm selection and algorithm performance/measurement uncertainty are even more significant for long range tracking of high-speed targets where temporally varying atmospheric effects degrade the imagery. This paper will present the preliminary results from a controlled test sequence used to characterize the performance of the TrackEye tracking algorithm suite.

  4. Putting struggling readers on the PHAST track: a program to integrate phonological and strategy-based remedial reading instruction and maximize outcomes.

    PubMed

    Lovett, M W; Lacerenza, L; Borden, S L

    2000-01-01

    PHAST (for Phonological and Strategy Training) is a research-based remedial reading program that attempts to capitalize upon current research on reading disabilities and their remediation. The focus of the program is on the primary obstacles to word identification learning and independent decoding that most disabled readers face and the steps necessary to help these children achieve independent reading skills. A framework of phonologically based remediation was used as a foundation upon which a set of flexible and effective word identification strategies were scaffolded in an integrated developmental sequence. The program uses a combination of direct instruction and dialogue-based metacognitive training, with the pedagogical emphasis shifting from an initial direct instruction, remedial focus to increasingly metacognitive-strategy-based methods. A continuum of intervention over 70 hours provides both (a) remediation of the basic phonological awareness and letter-sound-learning deficits of disabled readers and (b) specific training of five word identification strategies that offer different approaches to the decoding of unfamiliar words and exposure to different levels of subsyllabic segmentation. Explicit instruction in the application and monitoring of multiple word identification strategies and their application to text-reading activities continues throughout the PHAST Program. PHAST training provides the disabled reader with the opportunity to become a flexible reader who approaches new words in or out of context with multiple strategies and has the ability to evaluate the success of their application. The PHAST Program was developed following the controlled evaluation of its components in laboratory classroom settings and recent positive results from their sequential combination. PHAST represents a new integrated approach to programming in this area using instructional components that have already demonstrated their efficacy with children with severe reading

  5. Mechanisms underlying sporadic cerebral small vessel disease: insights from neuroimaging

    PubMed Central

    Wardlaw, JM; Smith, C; Dichgans, M

    2013-01-01

    The term “cerebral small vessel disease” (SVD) describes a range of neuroimaging, pathological and associated clinical features. The latter range from none, to discrete focal neurological symptoms (stroke), to insidious global neurological dysfunction and dementia. The public health burden is considerable. The pathogenesis is largely unknown. Although associated with vascular risk factors, and generally considered to result from an intrinsic cerebral arteriolar occlusive disease, the pathological processes leading to the arteriolar disease, how these result in brain disease, how SVD lesions contribute to neurological or cognitive symptoms and the relationship to risk factors, have been the subject of much speculation. Pathology often reflects end-stage disease making determination of the earliest stages difficult. Neuroimaging provides considerable insights: the small vessels are not easily seen themselves, but the effects of their malfunction on the brain can be tracked on detailed brain imaging. We review the growing evidence for the most likely mechanisms. PMID:23602162

  6. A novel multi-target ligand (JM-20) protects mitochondrial integrity, inhibits brain excitatory amino acid release and reduces cerebral ischemia injury in vitro and in vivo.

    PubMed

    Nuñez-Figueredo, Yanier; Ramírez-Sánchez, Jeney; Hansel, Gisele; Simões Pires, Elisa Nicoloso; Merino, Nelson; Valdes, Odalys; Delgado-Hernández, René; Parra, Alicia Lagarto; Ochoa-Rodríguez, Estael; Verdecia-Reyes, Yamila; Salbego, Christianne; Costa, Silvia L; Souza, Diogo O; Pardo-Andreu, Gilberto L

    2014-10-01

    We previously showed that JM-20, a novel 1,5-benzodiazepine fused to a dihydropyridine moiety, possessed an anxiolytic profile similar to diazepam and strong neuroprotective activity in different cell models relevant to cerebral ischemia. Here, we investigated whether JM-20 protects against ischemic neuronal damage in vitro and in vivo. The effects of JM-20 were evaluated on hippocampal slices subjected to oxygen and glucose deprivation (OGD). For in vivo studies, Wistar rats were subjected 90 min of middle cerebral artery occlusion (MCAo) and oral administration of JM-20 at 2, 4 and 8 mg/kg 1 h following reperfusion. Twenty-four hours after cerebral blood flow restoration, neurological deficits were scored, and the infarct volume, histopathological changes in cortex, number of hippocampal and striatal neurons, and glutamate/aspartate concentrations in the cerebrospinal fluid were measured. Susceptibility to brain mitochondrial swelling, membrane potential dissipation, H2O2 generation, cytochrome c release, Ca2+ accumulation, and morphological changes in the organelles were assessed 24 h post-ischemia. In vitro, JM-20 (1 and 10 μM) administered during reperfusion significantly reduced cell death in hippocampal slices subjected to OGD. In vivo, JM-20 treatment (4 and 8 mg/kg) significantly decreased neurological deficit scores, edema formation, total infarct volumes and histological alterations in different brain regions. JM-20 treatment also protected brain mitochondria from ischemic damage, most likely by preventing Ca2+ accumulation in organelles. Moreover, an 8-mg/kg JM-20 dose reduced glutamate and aspartate concentrations in cerebrospinal fluid and the deleterious effects of MCAo even when delivered 8 h after blood flow restoration. These results suggest that in rats, JM-20 is a robust neuroprotective agent against ischemia/reperfusion injury with a wide therapeutic window. Our findings support the further examination of potential clinical JM-20 use to treat

  7. Cerebral venous angiomas

    SciTech Connect

    Olson, E.; Gilmor, R.L.; Richmond, B.

    1984-04-01

    Several unusual cases of cerebral venous angiomas as well as some characteristic cases are reported. The characteristic angiographic feature is that of a collection of dilated medullary veins draining into a single large draining vein, which appears first in the early venous phase and persists into the late venous phase of the arteriogram. Computed tomography (CT) was abnormal in 12/13 cases. The draining vein was the most common abnormality identified on CT. Coronal and sagittal reconstruction may be helpful in demonstrating the draining vein. A case of large twin venous angiomas, a case of hemorrhage from a venous angioma, and a case of a venous angioma with an incidentally associated glioblastoma are presented.

  8. Track initiation of bearings-only tracking based on ant navigation concept

    NASA Astrophysics Data System (ADS)

    Zhu, Jihong; Xu, Benlian; Wang, Zhiquan

    2010-11-01

    A novel heuristic track initiation method is developed for the bearing-only multi-sensor-multi-target tracking system, in which each target is assumed to move with a straight line. The key idea of the proposed method is derived from the ant navigation concept in its foraging life, which differs from the traditional ant colony optimization algorithm, and it utilizes the concept of path integration and visual landmarks in ants' navigation toolkit to find the exact positions of each target. Numerous numerical simulations are conducted and the effectiveness of the proposed track initiation method is verified according to the probability of correct track initiation.

  9. Early GABAergic circuitry in the cerebral cortex.

    PubMed

    Luhmann, Heiko J; Kirischuk, Sergei; Sinning, Anne; Kilb, Werner

    2014-06-01

    In the cerebral cortex GABAergic signaling plays an important role in regulating early developmental processes, for example, neurogenesis, migration and differentiation. Transient cell populations, namely Cajal-Retzius in the marginal zone and thalamic input receiving subplate neurons, are integrated as active elements in transitory GABAergic circuits. Although immature pyramidal neurons receive GABAergic synaptic inputs already at fetal stages, they are integrated into functional GABAergic circuits only several days later. In consequence, GABAergic synaptic transmission has only a minor influence on spontaneous network activity during early corticogenesis. Concurrent with the gradual developmental shift of GABA action from excitatory to inhibitory and the maturation of cortical synaptic connections, GABA becomes more important in synchronizing neuronal network activity. PMID:24434608

  10. Cerebral Laterality and Verbal Processes

    ERIC Educational Resources Information Center

    Sherman, Jay L.; And Others

    1976-01-01

    Research suggests that we process information by way of two distinct and functionally separate coding systems. Their location, somewhat dependent on cerebral laterality, varies in right- and left-handed persons. Tests this dual coding model. (Editor/RK)

  11. Cognitive Deficits and Cerebral Asymmetry.

    ERIC Educational Resources Information Center

    Bakker, Dirk J.

    1982-01-01

    Research concerning cerebral asymmetry and its effect on scholastic achievement, reading disabilities, learning disabilities, and linguistic competence is reviewed in an exploration of brain hemisphere-specific etiologies of dyslexia. (CJ)

  12. To Track or Not to Track?

    ERIC Educational Resources Information Center

    Hesson, Heather

    2010-01-01

    Background: This paper was written for a graduate level action research course at Muskingum University, located in New Concord, OH. Purpose: The purpose of this research was to determine which method of instruction best serves ALL high school students. Is it more advantageous to track ("ability group") students or not to track students in high…

  13. Calculating track thrust with track functions

    NASA Astrophysics Data System (ADS)

    Chang, Hsi-Ming; Procura, Massimiliano; Thaler, Jesse; Waalewijn, Wouter J.

    2013-08-01

    In e+e- event shapes studies at LEP, two different measurements were sometimes performed: a “calorimetric” measurement using both charged and neutral particles and a “track-based” measurement using just charged particles. Whereas calorimetric measurements are infrared and collinear safe, and therefore calculable in perturbative QCD, track-based measurements necessarily depend on nonperturbative hadronization effects. On the other hand, track-based measurements typically have smaller experimental uncertainties. In this paper, we present the first calculation of the event shape “track thrust” and compare to measurements performed at ALEPH and DELPHI. This calculation is made possible through the recently developed formalism of track functions, which are nonperturbative objects describing how energetic partons fragment into charged hadrons. By incorporating track functions into soft-collinear effective theory, we calculate the distribution for track thrust with next-to-leading logarithmic resummation. Due to a partial cancellation between nonperturbative parameters, the distributions for calorimeter thrust and track thrust are remarkably similar, a feature also seen in LEP data.

  14. Iron Oxide as an MRI Contrast Agent for Cell Tracking

    PubMed Central

    Korchinski, Daniel J.; Taha, May; Yang, Runze; Nathoo, Nabeela; Dunn, Jeff F.

    2015-01-01

    Iron oxide contrast agents have been combined with magnetic resonance imaging for cell tracking. In this review, we discuss coating properties and provide an overview of ex vivo and in vivo labeling of different cell types, including stem cells, red blood cells, and monocytes/macrophages. Furthermore, we provide examples of applications of cell tracking with iron contrast agents in stroke, multiple sclerosis, cancer, arteriovenous malformations, and aortic and cerebral aneurysms. Attempts at quantifying iron oxide concentrations and other vascular properties are examined. We advise on designing studies using iron contrast agents including methods for validation. PMID:26483609

  15. Photographing Track Meets.

    ERIC Educational Resources Information Center

    Palmer, Erik

    2001-01-01

    Argues that the sport of track and field, because of the sport itself and its relatively easy access to photographers, is an obvious target for cameras. Discusses rules of the track that photographers must follow; picking a location; and equipment. Discusses shooting four specific track and field events and offers behind the scenes photos. (SR)

  16. Solar tracking apparatus

    DOEpatents

    Hammons, Burrell E.

    1980-01-01

    The invention relates to a solar tracking device which tracks the position of the sun using paired, partially-shaded photocells. Auxiliary photocells are used for initial acquisition of the sun and for the suppression of false tracking when the sun is obscured by clouds.

  17. Solar tracking apparatus

    DOEpatents

    Hammons, B.E.

    The invention relates to a solar tracking device which tracks the position of the sun using paired, partially-shaded photocells. Auxilliary photocells are used for initial acquisition of the sun and for the suppression of false tracking when the sun is obscured by clouds.

  18. Track and Field Facilities.

    ERIC Educational Resources Information Center

    Wood, Tony

    2001-01-01

    Discusses planning and design tips that help ensure track and field facilities are successful and well-suited to both school and community use. Examines approaches to determining the best track surface and ways to maximize track and field flexibility with limited space. (GR)

  19. Integrative Analysis of mRNA, microRNA, and Protein Correlates of Relative Cerebral Blood Volume Values in GBM Reveals the Role for Modulators of Angiogenesis and Tumor Proliferation

    PubMed Central

    Rao, Arvind; Manyam, Ganiraju; Rao, Ganesh; Jain, Rajan

    2016-01-01

    Dynamic susceptibility contrast-enhanced magnetic resonance imaging is routinely used to provide hemodynamic assessment of brain tumors as a diagnostic as well as a prognostic tool. Recently, it was shown that the relative cerebral blood volume (rCBV), obtained from the contrast-enhancing as well as -nonenhancing portion of glioblastoma (GBM), is strongly associated with overall survival. In this study, we aim to characterize the genomic correlates (microRNA, messenger RNA, and protein) of this vascular parameter. This study aims to provide a comprehensive radiogenomic and radioproteomic characterization of the hemodynamic phenotype of GBM using publicly available imaging and genomic data from the Cancer Genome Atlas GBM cohort. Based on this analysis, we identified pathways associated with angiogenesis and tumor proliferation underlying this hemodynamic parameter in GBM. PMID:27053917

  20. [Plasma osmolarity and cerebral volume].

    PubMed

    Boulard, G

    2001-02-01

    Under normal physiological conditions, the osmolarity of extracellular fluids (ECFs) and natremia are controlled by two regulatory mechanisms modulating the water balance and sodium outflow from information collected by the osmoreceptors and baroreceptors, respectively. As well, under normal physiological conditions, water and electrolytes of brain ECFs are secreted by the endothelial cells of brain capillaries. Furthermore, isotonicity is present on both sides of the blood-brain barrier. In the event of systemic osmolarity disorders, water transport subject to osmosis laws occurs at the level of the blood-brain barrier. In the case of plasmatic hyperosmolarity cerebral dehydration is observed, while cerebral edema occurs in the contrary case. However, plasmatic osmolarity disorders have less effect on the cerebral volume when their introduction is slow. Experimentation in acute conditions shows that measured variations of the cerebral water content are lower than calculated variations, thus suggesting the existence of an adaptive mechanism, that is, the cerebral osmoregulation which limits the variation of the volume of brain cells by modulating their osmoactive molecule content. These osmoactive molecules are, on the one hand, the electrolytes, which are early and rapidly mobilized, and, on the other hand, the organic osmoles (amino acids, etc.), whose secretion is slower and delayed. This phenomenon should be taken into account in the treatment of osmolarity disorders. Thus, the related-risk of treatment for natremia disorders is therapeutic reversal of the osmotic gradient at the level of the blood-brain barrier. This reversal, which corresponds to a second osmotic stress, requires the implementation of a new procedure of cerebral osmoregulation in the opposite direction of the preceding one. As successive osmotic stresses decrease the effectiveness of brain osmoregulation, the risk for cerebral dehydration and pontine myelinolysis increases when the treatment

  1. Finite resolution multitarget tracking

    NASA Astrophysics Data System (ADS)

    Mušicki, Darko; Morelande, Mark R.

    2005-09-01

    Target tracking algorithms have to operate in an environment of uncertain measurement origin, due to the presence of randomly detected target measurements as well as clutter measurements from unwanted random scatterers. A majority of Bayesian multi-target tracking algorithms suffer from computational complexity which is exponential in the number of tracks and the number of shared measurements. The Linear Multi-target (LM) tracking procedure is a Bayesian multi-target tracking approximation with complexity which is linear in the number of tracks and the number of shared measurements. It also has a much simpler structure than the "optimal" Bayesian multi-target tracking, with apparently negligible decrease in performance. A vast majority of target tracking algorithms have been developed with the assumption of infinite sensor resolution, where a measurement can have only one source. This assumption is not valid for real sensors, such as radars. This paper presents a multi-target tracking algorithm which removes this restriction. The procedure utilizes a simple structure of LM tracking procedure to obtain a LM Finite Resolution (LMfr) tracking procedure which is much simpler than the previously published efforts. Instead of calculating the probability of measurement merging for each combination of potentially merging targets, we evaluate only one merging hypotheses for each measurement and each track. A simulation study is presented which compares LMfr-IPDA with LM-IPDA and IPDA target tracking in a cluttered environment utilizing a finite resolution sensor with five crossing targets. The study concentrates on the false track discrimination performance and the track retention capabilities.

  2. Object tracking with stereo vision

    NASA Technical Reports Server (NTRS)

    Huber, Eric

    1994-01-01

    A real-time active stereo vision system incorporating gaze control and task directed vision is described. Emphasis is placed on object tracking and object size and shape determination. Techniques include motion-centroid tracking, depth tracking, and contour tracking.

  3. Vehicle track loading simulation

    NASA Astrophysics Data System (ADS)

    Chalupa, Milan; Severa, Libor; Vlach, Radek

    2011-12-01

    The paper describes possible design of the vehicle track computational model and basic testing procedure of the track dynamic loading simulation. The proposed approach leads to an improvement of track vehicle course stability. The computational model is built for MSC. ADAMS, AVT computational simulating system. Model, which is intended for MSC computational system, is built from two basic parts. The first one is represented by geometrical part, while the second one by contact computational part of the model. The aim of the simulating calculation consist in determination of change influence of specific vehicle track constructive parameters on changes of examined qualities of the vehicle track link and changes of track vehicle course stability. The work quantifies the influence of changes of track preloading values on the demanded torque changes of driving sprocket. Further research possibilities and potential are also presented.

  4. Hydrostatic determinants of cerebral perfusion

    SciTech Connect

    Wagner, E.M.; Traystman, R.J.

    1986-05-01

    We examined the cerebral blood flow response to alterations in perfusion pressure mediated through decreases in mean arterial pressure, increases in cerebrospinal fluid (CSF) pressure, and increases in jugular venous (JV) pressure in 42 pentobarbital anesthetized dogs. Each of these three pressures was independently controlled. Cerebral perfusion pressure was defined as mean arterial pressure minus JV or CSF pressure, depending on which was greater. Mean hemispheric blood flow was measured with the radiolabeled microsphere technique. Despite 30-mm Hg reductions in mean arterial pressure or increases in CSF or JV pressure, CBF did not change as long as the perfusion pressure remained greater than approximately 60 mm Hg. However, whenever perfusion pressure was reduced to an average of 48 mm Hg, cerebral blood flow decreased 27% to 33%. These results demonstrate the capacity of the cerebral vascular bed to respond similarly to changes in the perfusion pressure gradient obtained by decreasing mean arterial pressure, increasing JV pressure or increasing CSF pressure, and thereby support the above definition of cerebral perfusion pressure.

  5. Cerebral oximetry and cardiac arrest.

    PubMed

    Skhirtladze-Dworschak, Keso; Dworschak, Martin

    2013-12-01

    Cerebral oximetry is a Food and Drug Administration-approved technology that allows monitoring of brain oxygen saturation in accessible superficial brain cortex regions, which are amongst the most vulnerable in regard to ischemic or hypoxic injury. Since most oxygen in the area of interest is located in the venous compartment, the determined regional brain oxygen saturation approximately reflects the local balance between oxygen delivery and oxygen consumption. Major systemic alterations in blood oxygen content and oxygen delivery will be accompanied by corresponding changes in regional brain saturation. This systematic review, which is based on a Medline search, focuses on the characteristic changes in regional cerebral oxygen saturation that occur, when global oxygen supply to the brain ceases. It further highlights the potential application of cerebral oximetry in the management of cardiac arrest victims, the predictability of clinical outcome after global cerebral ischemia, and it also indicates possible potentials for the management of cerebral reperfusion after having instituted return of spontaneous circulation. PMID:23782549

  6. Cerebral palsy and aging

    PubMed Central

    Haak, Peterson; Lenski, Madeleine; Hidecker, Mary Jo Cooley; Li, Min; Paneth, Nigel

    2014-01-01

    Cerebral palsy (CP), the most common major disabling motor disorder of childhood, is frequently thought of as a condition that affects only children. Deaths in children with CP, never common, have in recent years become very rare, unless the child is very severely and multiply disabled. Thus, virtually all children assigned the diagnosis of CP will survive into adulthood. Attention to the adult with CP has been sparse, and the evolution of the motor disorder as the individual moves through adolescence, young adulthood, middle age, and old age is not well understood. Nor do we know what happens to other functional domains, such as communication and eating behavior, in adults with CP. Although the brain injury that initially causes CP by definition does not progressively worsen through the lifetime, the effects of CP manifest differently throughout the life span. The aging process must inevitably interact with the motor disorder, but we lack systematic, large-scale follow-up studies of children with CP into adulthood and through adulthood with thorough assessments performed over time. In this paper we summarize what is known of the epidemiology of CP throughout the life span, beginning with mortality and life expectancy, then survey what is known of functioning, ability, and quality of life of adults with CP. We conclude by describing a framework for future research on CP and aging that is built around the World Health Organization's International Classification of Functioning, Disability, and Health (ICF) and suggest specific tools and approaches for conducting that research in a sound manner. PMID:19740206

  7. Cerebritis: an unusual complication of Klebsiella pneumoniae.

    PubMed

    Majumdar, Mainak; Simes, David C; Prabha, Ramesh D

    2009-01-01

    Cerebritis is part of a continuum of brain infection and is difficult to diagnose. Cerebritis caused by Klebsiella in immunocompetent adults without predisposing factors such as neurosurgery or penetrating brain injury has not been reported before. We report a case of Klebsiella cerebritis in an adult patient with a proven extracranial focus of infection. We suggest considering cerebritis as a differential diagnosis for altered level of consciousness in patients of severe sepsis, even if an extracranial source of infection is proven. PMID:19881180

  8. Cerebritis: An unusual complication of Klebsiella pneumoniae

    PubMed Central

    Majumdar, Mainak; Simes1, David C.; Prabha1, Ramesh D.

    2009-01-01

    Cerebritis is part of a continuum of brain infection and is difficult to diagnose. Cerebritis caused by Klebsiella in immunocompetent adults without predisposing factors such as neurosurgery or penetrating brain injury has not been reported before. We report a case of Klebsiella cerebritis in an adult patient with a proven extracranial focus of infection. We suggest considering cerebritis as a differential diagnosis for altered level of consciousness in patients of severe sepsis, even if an extracranial source of infection is proven. PMID:19881180

  9. Multiple infected cerebral hydatid cysts.

    PubMed

    Gana, R; Skhissi, M; Maaqili, R; Bellakhdar, F

    2008-05-01

    We report an unusual patient with multiple infected cerebral hydatid cysts. A 20-year-old man presented with a 2-month history of headache and progressive left-sided hempiparesis. A cerebral CT scan showed a large and heterogeneous parieto-occipital lesion. During surgery an infected hydatid cyst was discovered with multiple daughter vesicles. Post-operatively the patient was treated with albendazol, cefotaxime and metronidazole. The clinical course was good with total recovery of the hemiparesis. A follow-up CT scan showed persistence of some small deep-seated cysts. Multiple infected cerebral hydatid cyst is uncommon and can be confused with other cystic brain lesions. The aim of surgery is to remove the cyst unruptured and this should be followed by antihelminthic and antibiotic treatment in order to avoid recurrences. PMID:18342511

  10. Oculoauriculovertebral spectrum and cerebral anomalies.

    PubMed Central

    Schrander-Stumpel, C T; de Die-Smulders, C E; Hennekam, R C; Fryns, J P; Bouckaert, P X; Brouwer, O F; da Costa, J J; Lommen, E J; Maaswinkel-Mooy, P D

    1992-01-01

    We report on three Dutch children with a clinical diagnosis of oculoauriculovertebral spectrum (OAVS) and hydrocephalus. The clinical features are compared to 15 published cases of OAVS and hydrocephalus. Several other cerebral abnormalities were present in the whole group. About half of the cases had cleft lip/palate, anophthalmia/microphthalmia, or a cardiac defect. Mental retardation was found in five of the surviving 11 patients and early death occurred in one-third. We compared the cases with OAVS and hydrocephalus with published reports of OAVS and other cerebral anomalies and found no significant clinical differences. However, the clinical characteristics were clearly more severely expressed than generally found in patients with OAVS. Children with OAVS and more severe clinical features, especially anophthalmia/microphthalmia and cleft lip/palate, seem to be at an increased risk for cerebral malformations and for mental retardation. Images PMID:1583660

  11. Tracking dynamic team activity

    SciTech Connect

    Tambe, M.

    1996-12-31

    AI researchers are striving to build complex multi-agent worlds with intended applications ranging from the RoboCup robotic soccer tournaments, to interactive virtual theatre, to large-scale real-world battlefield simulations. Agent tracking - monitoring other agent`s actions and inferring their higher-level goals and intentions - is a central requirement in such worlds. While previous work has mostly focused on tracking individual agents, this paper goes beyond by focusing on agent teams. Team tracking poses the challenge of tracking a team`s joint goals and plans. Dynamic, real-time environments add to the challenge, as ambiguities have to be resolved in real-time. The central hypothesis underlying the present work is that an explicit team-oriented perspective enables effective team tracking. This hypothesis is instantiated using the model tracing technology employed in tracking individual agents. Thus, to track team activities, team models are put to service. Team models are a concrete application of the joint intentions framework and enable an agent to track team activities, regardless of the agent`s being a collaborative participant or a non-participant in the team. To facilitate real-time ambiguity resolution with team models: (i) aspects of tracking are cast as constraint satisfaction problems to exploit constraint propagation techniques; and (ii) a cost minimality criterion is applied to constrain tracking search. Empirical results from two separate tasks in real-world, dynamic environments one collaborative and one competitive - are provided.

  12. Behaviour Problems Amongst Children With Cerebral Palsy.

    ERIC Educational Resources Information Center

    Oswin, Maureen

    Based on 6 years of work with cerebral palsied children, the thesis considers types and causes of cerebral palsy, the life pattern of the child with cerebral palsy from early years to adolescence, and the effect of the handicapped child on his parents and family. Literature on behavior disorders is reviewed, and kinds of behavior problems are…

  13. Neuroevolutional Approach to Cerebral Palsy and Speech.

    ERIC Educational Resources Information Center

    Mysak, Edward D.

    Intended for cerebral palsy specialists, the book emphasizes the contribution that a neuroevolutional approach to therapy can make to habilitation goals of the child with cerebral palsy and applies the basic principles of the Bobath approach to therapy. The first section discusses cerebral palsy as a reflection of disturbed neuro-ontogenisis and…

  14. Cerebral vasculitis associated with cocaine abuse

    SciTech Connect

    Kaye, B.R.; Fainstat, M.

    1987-10-16

    A case of cerebral vasculitis in a previously healthy 22-year-old man with a history of cocaine abuse is described. Cerebral angiograms showed evidence of vasculitis. A search for possible causes other than cocaine produced no results. The authors include cocaine with methamphetamines, heroin, and ephedrine as illicit drugs that can cause cerebral vasculitis.

  15. Cerebral Palsy: A Dental Update

    PubMed Central

    Sehrawat, Nidhi; Bansal, Kalpana; Chopra, Radhika

    2014-01-01

    ABSTRACT Special and medically compromised patients present a unique population that challenges the dentist’s skill and knowledge. Providing oral care to people with cerebral palsy (CP) requires adaptation of the skills we use everyday. In fact, most people with mild or moderate forms of CP can be treated successfully in the general practice setting. This article is to review various dental considerations and management of a CP patient. How to cite this article: Sehrawat N, Marwaha M, Bansal K, Chopra R. Cerebral Palsy: A Dental Update. Int J Clin Pediatr Dent 2014;7(2):109-118. PMID:25356010

  16. Complementary and alternative therapies for cerebral palsy.

    PubMed

    Liptak, Gregory S

    2005-01-01

    The optimal practice of medicine includes integrating individual clinical expertise with the best available clinical evidence from systematic research. This article reviews nine treatment modalities used for children who have cerebral palsy (CP), including hyperbaric oxygen, the Adeli Suit, patterning, electrical stimulation, conductive education, equine-assisted therapy, craniosacral therapy, Feldenkrais therapy, and acupuncture. Unfortunately, these modalities have different degrees of published evidence to support or refute their effectiveness. Uncontrolled and controlled trials of hippotherapy have shown beneficial effects on body structures and functioning. Studies of acupuncture are promising, but more studies are required before specific recommendations can be made. Most studies of patterning have been negative and its use cannot be recommended. However, for the other interventions, such as hyperbaric oxygen, more evidence is required before recommendations can be made. The individual with CP and his or her family have a right to full disclosure of all possible treatment options and whatever knowledge currently is available regarding these therapies. PMID:15977320

  17. Patterning the cerebral cortex: traveling with morphogens.

    PubMed

    Borello, Ugo; Pierani, Alessandra

    2010-08-01

    The neocortex represents the brain structure that has been subjected to a major expansion in its relative size during the course of mammalian evolution. An exquisite coordination of appropriate growth of competent territories along multiple axes and their spatial patterning is required for regionalization of the cortical primordium and the formation of functional areas. The achievement of such a highly complex architecture relies on a precise orchestration of the proliferation of progenitors, onset of neurogenesis, spatio-temporal generation of distinct cell types and control of their migration. We will review recent work on alternative molecular mechanisms that, via the migration of signaling cells/structures, participate in coordinating growth and spatial patterning in the developing cerebral cortex. By integrating temporal and spatial parameters as well as absolute levels of signaling this novel strategy might represent a general mechanism for long-range patterning in large structures, in addition to the passive diffusion of morphogens. PMID:20542680

  18. Correlation tracking for a Planetary Pointing and Tracking System

    NASA Technical Reports Server (NTRS)

    Assefi, T.

    1978-01-01

    The Planetary Pointing and Tracking System (PPTS) is being developed to provide precision pointing for science platforms on future autonomous planetary spacecraft. The PPTS design approach using a CCD optical sensor for closed-loop control with respect to the target body, a gyro for inertial stabilization, and brushless dc torque motors for smooth and continuous platform articulation is essential for high resolution planetary imaging and automated science execution. An integral part of PPTS is the correlation tracker which has the potential to revolutionize autonomous guidance.

  19. Inflammation, Cerebral Vasospasm, and Evolving Theories of Delayed Cerebral Ischemia

    PubMed Central

    Carr, Kevin R.; Zuckerman, Scott L.; Mocco, J

    2013-01-01

    Cerebral vasospasm (CVS) is a potentially lethal complication of aneurysmal subarachnoid hemorrhage (aSAH). Recently, the symptomatic presentation of CVS has been termed delayed cerebral ischemia (DCI), occurring as early as 3-4 days after the sentinel bleed. For the past 5-6 decades, scientific research has promulgated the theory that cerebral vasospasm plays a primary role in the pathology of DCI and subsequently delayed ischemic neurological decline (DIND). Approximately 70% of patients develop CVS after aSAH with 50% long-term morbidity rates. The exact etiology of CVS is unknown; however, a well-described theory involves an antecedent inflammatory cascade with alterations of intracellular calcium dynamics and nitric oxide fluxes, though the intricacies of this inflammatory theory are currently unknown. Consequently, there have been few advances in the clinical treatment of this patient cohort, and morbidity remains high. Identification of intermediaries in the inflammatory cascade can provide insight into newer clinical interventions in the prevention and management of cerebral vasospasm and will hopefully prevent neurological decline. In this review, we discuss current theories implicating the inflammatory cascade in the development of CVS and potential treatment targets. PMID:24058736

  20. Radiosurgery for cerebral cavernomas.

    PubMed

    Nagy, G; Kemeny, A A

    2015-09-01

    The role of stereotactic radiosurgery (SRS) in the management of cerebral cavernomas (CCMs) remains controversial. However, during the last decade the increasing knowledge on natural history and numerous publications from SRS centers using modern treatment protocols has been changing the initial resistance of the neurosurgical community. Unfortunately, the quality of publications on CCM SRS remains heterogeneous. Controversies arise from the lack of control groups, the different definition of hemorrhage, heterogeneous patient populations, and poor definition of treatment protocols. The key for proper interpretation of results is the understanding of the natural history of CCMs, which is varied both according to anatomical location and the presence or absence of previous hemorrhage. Hemispheric lesions appear to be more benign with lower annual bleed rate and risk of persisting disability, whereas those found in the thalamus, basal ganglia and brainstem typically have higher rebleed risk resulting in higher cumulative morbidity following subsequent hemorrhages. However, we are still unable at presentation to predict the future behavior of an individual lesion. In the present paper we critically review and analyze the modern SRS literature on CCMs. The expanding number of available data with current treatment protocols strongly supports the initial intuition that SRS is an effective treatment alternative for deep-seated CCMs with multiple hemorrhages reducing pretreatment annual rebleed rates from 32% pre-treatment to 1.5% within 2 years after treatment (N.=197). Moreover, it appears to stabilize lesions with no more than one bleed, and it is also effective for CCMs causing therapy resistant epilepsy especially if applied within 3 years after presentation. In modern SRS series the rate of persisting adverse radiation effects is low, resulting only in mild morbidity even in deep-seated lesions (4.16%, N.=376), and morbidity caused by post-treatment hemorrhages is also

  1. Cerebral circulatory and metabolic effects of 5-hydroxytryptamine in anesthetized baboons.

    PubMed Central

    Harper, M A; MacKenzie, E T

    1977-01-01

    1. The cerebral circulatory effects of the intracarotid administration of 5-hydroxytryptamine were examined in anaesthetized baboons. Cerebral blood flow was measured by the intracarotid 133Xe technique, cerebral O2 consumption and glucose uptake were measured as indices of brain metabolism and electrocortical activity was continuously monitored. 2. Despite a marked reduction in the calibre of the internal carotid artery (assessed angiographically), the intracarotid infusion of 5-hydroxytryptamine 0-1 microgram/kg. min did not effect any significant changes in cerebral blood flow, O2 consumption or glucose uptake. 3. Following transient osmotic disruption of the blood-brain barrier with the intracarotid infusion of hypertonic urea, the same dose of 5-hydroxytryptamine effected a marked reduction in cerebral blood flow from 51 +/- 2 to 36 +/- 2 ml./100 g. min (mean +/- S.E.; P less than 0-01). Both indices of cerebral metabolism were reduced significantly and the e.e.g. showed a more pronounced suppression-burst pattern. 4. We postulate that the cerebral circulatory responses to 5-hydroxytryptamine are dependent upon the integrity of the blood-brain barrier and the predominant effect of the intravascular administration of 5-hydroxytryptamine is on cortical activity or metabolism, rather than on cerebrovascular smooth muscle. Images Plate 1 PMID:411921

  2. Tracking toxic chemicals

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    A new report tracking industrial pollution in North America indicates some good news, in terms of downward trends in the release and transfer of these substances.The July report, which tracks 165 chemicals released in the United States and Canada, shows that the total amount of 3.2 million tonnes of chemical releases and transfers from industrial facilities tracked by the North American Commission for Environmental Cooperation (CEC) decreased by 2% overall from 1995 to 1998.

  3. Structural network alterations and neurological dysfunction in cerebral amyloid angiopathy.

    PubMed

    Reijmer, Yael D; Fotiadis, Panagiotis; Martinez-Ramirez, Sergi; Salat, David H; Schultz, Aaron; Shoamanesh, Ashkan; Ayres, Alison M; Vashkevich, Anastasia; Rosas, Diana; Schwab, Kristin; Leemans, Alexander; Biessels, Geert-Jan; Rosand, Jonathan; Johnson, Keith A; Viswanathan, Anand; Gurol, M Edip; Greenberg, Steven M

    2015-01-01

    markers of small-vessel disease. These findings suggest that reduced structural brain network efficiency might mediate the relationship between advanced cerebral amyloid angiopathy and neurologic dysfunction and that such large-scale brain network measures may represent useful outcome markers for tracking disease progression. PMID:25367025

  4. SimTrack: A compact c++ code for particle orbit and spin tracking in accelerators

    SciTech Connect

    Luo, Yun

    2015-08-29

    SimTrack is a compact c++ code of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam–beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam–beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam–beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this article, I will present the code architecture, physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.

  5. SimTrack: A compact c++ library for particle orbit and spin tracking in accelerators

    SciTech Connect

    Luo, Yun

    2015-06-24

    SimTrack is a compact c++ library of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam-beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam-beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam-beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this article, I will present the code architecture, physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.

  6. SimTrack: A compact c++ code for particle orbit and spin tracking in accelerators

    DOE PAGESBeta

    Luo, Yun

    2015-08-29

    SimTrack is a compact c++ code of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam–beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam–beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam–beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this article, I will present the code architecture,more » physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.« less

  7. Sim Track User's Manual (v 1.0)

    SciTech Connect

    Luo, Y.

    2010-01-27

    SimTrack is a simple c++ library designed for the numeric particle tracking in the high energy accelerators. It adopts the 4th order symplectic integrator for the optical transport in the magnetic elements. The 4-D and 6-D weak-strong beam-beam treatments are integrated in it for the beam-beam studies. SimTrack is written with c++ class and standard template library. It provides versatile functions to manage elements and lines. It supports a large range of types of elements. New type of element can be easily created in the library. SimTrack calculates Twiss, coupling and fits tunes, chromaticities and corrects closed orbits. AC dipole and AC multipole are available in this library. SimTrack allows change of element parameters during tracking.

  8. Nanodosimetric track structure in homogeneous extended beams.

    PubMed

    Conte, V; Moro, D; Colautti, P; Grosswendt, B

    2015-09-01

    Physical aspects of particle track structure are important in determining the induction of clustered damage in relevant subcellular structures like the DNA and higher-order genomic structures. The direct measurement of track-structure properties of ionising radiation is feasible today by counting the number of ionisations produced inside a small gas volume. In particular, the so-called track-nanodosimeter, installed at the TANDEM-ALPI accelerator complex of LNL, measures ionisation cluster-size distributions in a simulated subcellular structure of dimensions 20 nm, corresponding approximately to the diameter of the chromatin fibre. The target volume is irradiated by pencil beams of primary particles passing at specified impact parameter. To directly relate these measured track-structure data to radiobiological measurements performed in broad homogeneous particle beams, these data can be integrated over the impact parameter. This procedure was successfully applied to 240 MeV carbon ions and compared with Monte Carlo simulations for extended fields. PMID:25848108

  9. Tracking in anatomic pathology.

    PubMed

    Pantanowitz, Liron; Mackinnon, Alexander C; Sinard, John H

    2013-12-01

    Bar code-based tracking solutions, long present in clinical pathology laboratories, have recently made an appearance in anatomic pathology (AP) laboratories. Tracking of AP "assets" (specimens, blocks, slides) can enhance laboratory efficiency, promote patient safety, and improve patient care. Routing of excess clinical material into research laboratories and biorepositories are other avenues that can benefit from tracking of AP assets. Implementing tracking is not as simple as installing software and turning it on. Not all tracking solutions are alike. Careful analysis of laboratory workflow is needed before implementing tracking to assure that this solution will meet the needs of the laboratory. Such analysis will likely uncover practices that may need to be modified before a tracking system can be deployed. Costs that go beyond simply that of purchasing software will be incurred and need to be considered in the budgeting process. Finally, people, not technology, are the key to assuring quality. Tracking will require significant changes in workflow and an overall change in the culture of the laboratory. Preparation, training, buy-in, and accountability of the people involved are crucial to the success of this process. This article reviews the benefits, available technology, underlying principles, and implementation of tracking solutions for the AP and research laboratory. PMID:23634908

  10. Cerebral ischemia during surgery: an overview

    PubMed Central

    Zhou, Zhi-Bin; Meng, Lingzhong; Gelb, Adrian W; Lee, Roger; Huang, Wen-Qi

    2016-01-01

    Abstract Cerebral ischemia is the pathophysiological condition in which the oxygenated cerebral blood flow is less than what is needed to meet cerebral metabolic demand. It is one of the most debilitating complications in the perioperative period and has serious clinical sequelae. The monitoring and prevention of intraoperative cerebral ischemia are crucial because an anesthetized patient in the operating room cannot be neurologically assessed. In this paper, we provide an overview of the definition, etiology, risk factors, and prevention of cerebral ischemia during surgery.

  11. Caffeine induced changes in cerebral circulation

    SciTech Connect

    Mathew, R.J.; Wilson, W.H.

    1985-09-01

    While the caffeine induced cerebral vasoconstriction is well documented, the effects of oral ingestion of the drug in a dose range comparable to the quantities in which it is usually consumed and the intensity and duration of the associated reduction in cerebral circulation are unknown. Cerebral blood flow was measured via the TTXenon inhalation technique before and thirty and ninety minutes after the oral administration of 250 mg of caffeine or a placebo, under double-blind conditions. Caffeine ingestion was found to be associated with significant reductions in cerebral perfusion thirty and ninety minutes later. The placebo group showed no differences between the three sets of cerebral blood flow values.

  12. [Cerebral ischemia in young adults].

    PubMed

    Berlit, P; Endemann, B; Vetter, P

    1991-08-01

    An overview is given over etiology and prognosis of cerebral ischemias until the age of 40. In a time period of 19 years, 168 patients were diagnosed with cerebral ischemia until the age of 40 (91 females, 77 males). The most frequent etiology is premature atherosclerosis in patients with vascular risk factors (up to 50%). Cardiogenic embolism is responsible for 1 to 34% of the cases: cardiac valve diseases and endocarditis being the most frequent sources. In 2 to 19% a vasculitis is diagnosed. While infectious arteritis is especially frequent in countries of the third world, immunovasculitides are common in Europe and the USA. Noninflammatory vasculopathies include spontaneous or traumatic dissection, fibromuscular dysplasia and vascular malformations. A migrainous stroke is especially frequent in female smokers with intake of oral contraceptives. During pregnancy both sinus thrombosis and arterial ischemia occur. Hematologic causes for ischemia are polycythemia, thrombocytosis and genetic diseases (sickle cell anemia, AT3-deficiency). Cerebral ischemia may occur in connection with the ingestion of ergot-derivates. The prognosis of cerebral ischemia in young adults is better than in older stroke-patients. PMID:1937340

  13. Innervation of the cerebral vasculature.

    PubMed

    Duckles, S P

    1983-01-01

    With the development of specific antibodies to vasoactive peptides and application of immunohistochemistry and radioimmunoassay methods, knowledge of vascular innervation has grown rapidly. In the cerebral circulation, four possible neurotransmitters are present: norepinephrine, acetylcholine, vasoactive intestinal peptide (VIP), and substance P. There is a dense adrenergic innervation of cerebral arteries, but contractile responses to nerve stimulation or circulating catecholamines are relatively small both in vitro and in vivo. Recent studies using radioligand binding techniques indicate a lack of specific 3H-prazosin binding in cerebral arteries, in contrast to other vascular beds. Thus a lack of alpha1-adrenergic receptors in cerebral arteries may account for weak responsiveness to sympathetic stimulation. Both VIP and acetylcholine may be vasodilator neurotransmitters, but blockade of cholinergic responses does not alter neurogenic vasodilation. The lack of specific VIP antagonists hampers efforts to explore this system more fully. Substance P-containing nerves are affected by capsaicin, supporting the hypothesis that these are primary sensory afferents, perhaps mediating pain. Future work in this area may focus on defining the pathways of these nerves and exploring the role of co-transmitters and possible interactions between nerves. With this basic information, experiments can be designed to elucidate more clearly the functional roles these nerves play. PMID:6210001

  14. Neuropathology of Acquired Cerebral Trauma.

    ERIC Educational Resources Information Center

    Bigler, Erin D.

    1987-01-01

    To help educators understand the cognitive and behavioral sequelae of cerebral injury, the neuropathology of traumatic brain injury and the main neuropathological features resulting from trauma-related brain damage are reviewed. A glossary with definitions of 37 neurological terms is appended. (Author/DB)

  15. Optimal Appearance Model for Visual Tracking

    PubMed Central

    Wang, Yuru; Jiang, Longkui; Liu, Qiaoyuan; Yin, Minghao

    2016-01-01

    Many studies argue that integrating multiple cues in an adaptive way increases tracking performance. However, what is the definition of adaptiveness and how to realize it remains an open issue. On the premise that the model with optimal discriminative ability is also optimal for tracking the target, this work realizes adaptiveness and robustness through the optimization of multi-cue integration models. Specifically, based on prior knowledge and current observation, a set of discrete samples are generated to approximate the foreground and background distribution. With the goal of optimizing the classification margin, an objective function is defined, and the appearance model is optimized by introducing optimization algorithms. The proposed optimized appearance model framework is embedded into a particle filter for a field test, and it is demonstrated to be robust against various kinds of complex tracking conditions. This model is general and can be easily extended to other parameterized multi-cue models. PMID:26789639

  16. Optimal Appearance Model for Visual Tracking.

    PubMed

    Wang, Yuru; Jiang, Longkui; Liu, Qiaoyuan; Yin, Minghao

    2016-01-01

    Many studies argue that integrating multiple cues in an adaptive way increases tracking performance. However, what is the definition of adaptiveness and how to realize it remains an open issue. On the premise that the model with optimal discriminative ability is also optimal for tracking the target, this work realizes adaptiveness and robustness through the optimization of multi-cue integration models. Specifically, based on prior knowledge and current observation, a set of discrete samples are generated to approximate the foreground and background distribution. With the goal of optimizing the classification margin, an objective function is defined, and the appearance model is optimized by introducing optimization algorithms. The proposed optimized appearance model framework is embedded into a particle filter for a field test, and it is demonstrated to be robust against various kinds of complex tracking conditions. This model is general and can be easily extended to other parameterized multi-cue models. PMID:26789639

  17. Aortic emboli show surprising size dependent predilection for cerebral arteries: Results from computational fluid dynamics

    NASA Astrophysics Data System (ADS)

    Carr, Ian; Schwartz, Robert; Shadden, Shawn

    2012-11-01

    Cardiac emboli can have devastating consequences if they enter the cerebral circulation, and are the most common cause of embolic stroke. Little is known about relationships of embolic origin/density/size to cerebral events; as these relationships are difficult to observe. To better understand stoke risk from cardiac and aortic emboli, we developed a computational model to track emboli from the heart to the brain. Patient-specific models of the human aorta and arteries to the brain were derived from CT angiography from 10 MHIF patients. Blood flow was modeled by the Navier-Stokes equations using pulsatile inflow at the aortic valve, and physiologic Windkessel models at the outlets. Particulate was injected at the aortic valve and tracked using modified Maxey-Riley equations with a wall collision model. Results demonstrate aortic emboli that entered the cerebral circulation through the carotid or vertebral arteries were localized to specific locations of the proximal aorta. The percentage of released particles embolic to the brain markedly increased with particle size from 0 to ~1-1.5 mm in all patients. Larger particulate became less likely to traverse the cerebral vessels. These findings are consistent with sparse literature based on transesophageal echo measurements. This work was supported in part by the National Science Foundation, award number 1157041.

  18. Reversible Cerebral Vasoconstriction Syndrome, Part 2: Diagnostic Work-Up, Imaging Evaluation, and Differential Diagnosis.

    PubMed

    Miller, T R; Shivashankar, R; Mossa-Basha, M; Gandhi, D

    2015-09-01

    The diagnostic evaluation of a patient with reversible cerebral vasoconstriction syndrome integrates clinical, laboratory, and radiologic findings. Imaging plays an important role by confirming the presence of cerebral vasoconstriction; monitoring potential complications such as ischemic stroke; and suggesting alternative diagnoses, including CNS vasculitis and aneurysmal subarachnoid hemorrhage. Noninvasive vascular imaging, including transcranial Doppler sonography and MR angiography, has played an increasingly important role in this regard, though conventional angiography remains the criterion standard for the evaluation of cerebral artery vasoconstriction. Newer imaging techniques, including high-resolution vessel wall imaging, may help in the future to better discriminate reversible cerebral vasoconstriction syndrome from primary angiitis of the CNS, an important clinical distinction. PMID:25614476

  19. Eye Tracking Young Children with Autism

    PubMed Central

    Sasson, Noah J.; Elison, Jed T.

    2012-01-01

    The rise of accessible commercial eye-tracking systems has fueled a rapid increase in their use in psychological and psychiatric research. By providing a direct, detailed and objective measure of gaze behavior, eye-tracking has become a valuable tool for examining abnormal perceptual strategies in clinical populations and has been used to identify disorder-specific characteristics1, promote early identification2, and inform treatment3. In particular, investigators of autism spectrum disorders (ASD) have benefited from integrating eye-tracking into their research paradigms4-7. Eye-tracking has largely been used in these studies to reveal mechanisms underlying impaired task performance8 and abnormal brain functioning9, particularly during the processing of social information1,10-11. While older children and adults with ASD comprise the preponderance of research in this area, eye-tracking may be especially useful for studying young children with the disorder as it offers a non-invasive tool for assessing and quantifying early-emerging developmental abnormalities2,12-13. Implementing eye-tracking with young children with ASD, however, is associated with a number of unique challenges, including issues with compliant behavior resulting from specific task demands and disorder-related psychosocial considerations. In this protocol, we detail methodological considerations for optimizing research design, data acquisition and psychometric analysis while eye-tracking young children with ASD. The provided recommendations are also designed to be more broadly applicable for eye-tracking children with other developmental disabilities. By offering guidelines for best practices in these areas based upon lessons derived from our own work, we hope to help other investigators make sound research design and analysis choices while avoiding common pitfalls that can compromise data acquisition while eye-tracking young children with ASD or other developmental difficulties. PMID:22491039

  20. Can Tracking Improve Learning?

    ERIC Educational Resources Information Center

    Duflo, Esther; Dupas, Pascaline; Kremer, Michael

    2009-01-01

    Tracking students into different classrooms according to their prior academic performance is controversial among both scholars and policymakers. If teachers find it easier to teach a homogeneous group of students, tracking could enhance school effectiveness and raise test scores of both low- and high-ability students. If students benefit from…

  1. On the Wrong Track.

    ERIC Educational Resources Information Center

    Black, Susan

    1992-01-01

    By any measure--student achievement, social development, or democratic values--ability grouping and tracking practices are indefensible and unsupported by research. Tracking allows schools to practice in-school segregation and perpetuate unequal opportunities and unequal socialization within classrooms. Jonathan Kozol's investigation shows how…

  2. Large scale tracking algorithms.

    SciTech Connect

    Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett; Karelitz, David B.; Pitts, Todd Alan; Zollweg, Joshua David; Anderson, Dylan Z.; Nandy, Prabal; Whitlow, Gary L.; Bender, Daniel A.; Byrne, Raymond Harry

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  3. Explaining cloud chamber tracks

    SciTech Connect

    Broyles, A.A.

    1992-06-16

    The operation of many detection devices is usually explained in terms of the ionization tracks produced by particles despite the fact that the corresponding incident wave functions extended over the entire sensitive regions of the detectors. The mechanisms by which the wave function appears to collapse to a track is analyzed here.

  4. TMDL TRACKING SYSTEM

    EPA Science Inventory

    Resource Purpose:The TMDL Tracking System database contains information on the waters listed under section 303(d) of the Clean Water Act and to track those listed waters through TMDL development. The purpose of the database is to allow EPA, the States/Territories/Tribes, ...

  5. Incentives from Curriculum Tracking

    ERIC Educational Resources Information Center

    Koerselman, Kristian

    2013-01-01

    Curriculum tracking creates incentives in the years before its start, and we should therefore expect test scores to be higher during those years. I find robust evidence for incentive effects of tracking in the UK based on the UK comprehensive school reform. Results from the Swedish comprehensive school reform are inconclusive. Internationally, I…

  6. Track record in meteorites

    NASA Astrophysics Data System (ADS)

    Durrani, S. A.

    1981-02-01

    The use of nuclear-track analysis in meteoritic crystals with reference to several areas of research is reviewed. The applications discussed include: fission-track retention ages and cooling rates of meteoritic parent bodies, cosmic-ray studies, determination of pre-atmospheric sizes of meteorites, and search for superheavy elements.

  7. 2 Tracks for Faculty

    ERIC Educational Resources Information Center

    Wilson, Robin

    2012-01-01

    The academic work force has been transformed over the past several decades, less by design than out of expediency. In 1969, professors who were either tenured or tenure-track made up 78 percent of the faculty. Those working part time made up only 18.5 percent. By 2009, those proportions had almost flipped, with tenured and tenure-track making up…

  8. UWB Tracking Software Development

    NASA Technical Reports Server (NTRS)

    Gross, Julia; Arndt, Dickey; Ngo, Phong; Phan, Chau; Dusl, John; Ni, Jianjun; Rafford, Melinda

    2006-01-01

    An Ultra-Wideband (UWB) two-cluster Angle of Arrival (AOA) tracking prototype system is currently being developed and tested at NASA Johnson Space Center for space exploration applications. This talk discusses the software development efforts for this UWB two-cluster AOA tracking system. The role the software plays in this system is to take waveform data from two UWB radio receivers as an input, feed this input into an AOA tracking algorithm, and generate the target position as an output. The architecture of the software (Input/Output Interface and Algorithm Core) will be introduced in this talk. The development of this software has three phases. In Phase I, the software is mostly Matlab driven and calls C++ socket functions to provide the communication links to the radios. This is beneficial in the early stage when it is necessary to frequently test changes in the algorithm. Phase II of the development is to have the software mostly C++ driven and call a Matlab function for the AOA tracking algorithm. This is beneficial in order to send the tracking results to other systems and also to improve the tracking update rate of the system. The third phase is part of future work and is to have the software completely C++ driven with a graphics user interface. This software design enables the fine resolution tracking of the UWB two-cluster AOA tracking system.

  9. COMPLIANCE AND ENFORCEMENT REGIONAL TRACKING SYSTEM (CERTS)

    EPA Science Inventory

    The Compliance and Enforcement Regional Tracking System (CERTS) is a system that allows Region 10 employees integrated access to information in EPA national media data bases through the LAN system. CERTS will allow you to identify regulated facilities in a given location such as...

  10. Air Research Program: Susceptibility Research Track

    EPA Science Inventory

    The susceptibility research track is focused on susceptibility due to life stage, disease state, and genetics. For each aspect, wherever possible an integrative cross-disciplinary approach is used that combines in vitro mechanistic studies with animal models and human clinical an...

  11. Leveraging Information Technology. Track V: Communications.

    ERIC Educational Resources Information Center

    CAUSE, Boulder, CO.

    Seven papers from the 1987 CAUSE conference's Track V, Communications, are presented. They include: "University of Miami LAN: A Case Study" (Ruben Lopez and M. Lewis Temares); "Designing and Implementing an Integrated Communications Environment in a Small College" (Charles S. Garratt IV, Jack M. Lewis, and John L. Van Hemert); "Commonwealth of…

  12. Leveraging Information Technology. Track IV: Support Services.

    ERIC Educational Resources Information Center

    CAUSE, Boulder, CO.

    Seven papers from the 1987 CAUSE conference's Track IV, Support Services, are presented. They include: "Application Development Center" (John F. Leydon); "College Information Management System: The Design and Implementation of a Completely Integrated Office Automation and Student Information System" (Karen L. Miselis); "Improving Managerial…

  13. Whole-rock uranium analysis by fission track activation

    NASA Technical Reports Server (NTRS)

    Weiss, J. R.; Haines, E. L.

    1974-01-01

    We report a whole-rock uranium method in which the polished sample and track detector are separated in a vacuum chamber. Irradiation with thermal neutrons induces uranium fission in the sample, and the detector records the integrated fission track density. Detection efficiency and geometric factors are calculated and compared with calibration experiments.

  14. A Novel Architecture of Radio Tracking System Based on Photonics

    NASA Astrophysics Data System (ADS)

    Cong, Bo; Jin, Xiaofeng; Yu, Xinfeng

    2016-02-01

    We propose a photonics-based novel architecture of radio tracking system in space applications. This system can operate in multiple frequency bands, implement various functions, and realize integrated, generalized, frequency-independent design. This new scheme can meet the needs of future space missions, and especially suitable for space tracking ship.

  15. TRACKED VEHICLE Rev 75

    SciTech Connect

    Raby, Eric Y.

    2007-05-08

    Revision 75 of the Tracked Vehicle software is a soft real-time simulation of a differentially steered, tracked mobile robot, which, because of the track flippers, resembles the iRobot PackBot (http://www.irobot.com/). Open source libraries are used for the physics engine (http://www.ode.org/), the display and user interface (http://www.mathies.com/cpw/), and the program command line and configuration file parameters (http://www.boost.org/). The simulation can be controlled by a USB joystick or the keyboard. The configuration file contains demonstration model parameters of no particular vehicle. This simulation can be used as a starting point for those doing tracked vehicle simulations. This simulation software is essentially a research tool which can be modified and adapted for certain types of tracked vehicle research. An open source license allows an individual researchers to tailor the code to their specific research needs.

  16. TRACKED VEHICLE Rev 75

    Energy Science and Technology Software Center (ESTSC)

    2007-05-08

    Revision 75 of the Tracked Vehicle software is a soft real-time simulation of a differentially steered, tracked mobile robot, which, because of the track flippers, resembles the iRobot PackBot (http://www.irobot.com/). Open source libraries are used for the physics engine (http://www.ode.org/), the display and user interface (http://www.mathies.com/cpw/), and the program command line and configuration file parameters (http://www.boost.org/). The simulation can be controlled by a USB joystick or the keyboard. The configuration file contains demonstration model parametersmore » of no particular vehicle. This simulation can be used as a starting point for those doing tracked vehicle simulations. This simulation software is essentially a research tool which can be modified and adapted for certain types of tracked vehicle research. An open source license allows an individual researchers to tailor the code to their specific research needs.« less

  17. CerebralWeb: a Cytoscape.js plug-in to visualize networks stratified by subcellular localization

    PubMed Central

    Frias, Silvia; Bryan, Kenneth; Brinkman, Fiona S. L.; Lynn, David J.

    2015-01-01

    CerebralWeb is a light-weight JavaScript plug-in that extends Cytoscape.js to enable fast and interactive visualization of molecular interaction networks stratified based on subcellular localization or other user-supplied annotation. The application is designed to be easily integrated into any website and is configurable to support customized network visualization. CerebralWeb also supports the automatic retrieval of Cerebral-compatible localizations for human, mouse and bovine genes via a web service and enables the automated parsing of Cytoscape compatible XGMML network files. CerebralWeb currently supports embedded network visualization on the InnateDB (www.innatedb.com) and Allergy and Asthma Portal (allergen.innatedb.com) database and analysis resources. Database tool URL: http://www.innatedb.com/CerebralWeb PMID:25953080

  18. CerebralWeb: a Cytoscape.js plug-in to visualize networks stratified by subcellular localization.

    PubMed

    Frias, Silvia; Bryan, Kenneth; Brinkman, Fiona S L; Lynn, David J

    2015-01-01

    CerebralWeb is a light-weight JavaScript plug-in that extends Cytoscape.js to enable fast and interactive visualization of molecular interaction networks stratified based on subcellular localization or other user-supplied annotation. The application is designed to be easily integrated into any website and is configurable to support customized network visualization. CerebralWeb also supports the automatic retrieval of Cerebral-compatible localizations for human, mouse and bovine genes via a web service and enables the automated parsing of Cytoscape compatible XGMML network files. CerebralWeb currently supports embedded network visualization on the InnateDB (www.innatedb.com) and Allergy and Asthma Portal (allergen.innatedb.com) database and analysis resources. Database tool URL: http://www.innatedb.com/CerebralWeb PMID:25953080

  19. Knowledge-based tracking algorithm

    NASA Astrophysics Data System (ADS)

    Corbeil, Allan F.; Hawkins, Linda J.; Gilgallon, Paul F.

    1990-10-01

    This paper describes the Knowledge-Based Tracking (KBT) algorithm for which a real-time flight test demonstration was recently conducted at Rome Air Development Center (RADC). In KBT processing, the radar signal in each resolution cell is thresholded at a lower than normal setting to detect low RCS targets. This lower threshold produces a larger than normal false alarm rate. Therefore, additional signal processing including spectral filtering, CFAR and knowledge-based acceptance testing are performed to eliminate some of the false alarms. TSC's knowledge-based Track-Before-Detect (TBD) algorithm is then applied to the data from each azimuth sector to detect target tracks. In this algorithm, tentative track templates are formed for each threshold crossing and knowledge-based association rules are applied to the range, Doppler, and azimuth measurements from successive scans. Lastly, an M-association out of N-scan rule is used to declare a detection. This scan-to-scan integration enhances the probability of target detection while maintaining an acceptably low output false alarm rate. For a real-time demonstration of the KBT algorithm, the L-band radar in the Surveillance Laboratory (SL) at RADC was used to illuminate a small Cessna 310 test aircraft. The received radar signal wa digitized and processed by a ST-100 Array Processor and VAX computer network in the lab. The ST-100 performed all of the radar signal processing functions, including Moving Target Indicator (MTI) pulse cancelling, FFT Doppler filtering, and CFAR detection. The VAX computers performed the remaining range-Doppler clustering, beamsplitting and TBD processing functions. The KBT algorithm provided a 9.5 dB improvement relative to single scan performance with a nominal real time delay of less than one second between illumination and display.

  20. Infrared-based object tracking

    NASA Astrophysics Data System (ADS)

    Gervais, Jon; Youngblood, Austin; Delashmit, Walter H.

    2009-05-01

    Often it is necessary to track moving objects on horizontal paths. Human error and the associated cost and dangers of using humans lead to a requirement to automate this task. The system presented here was designed, built and tested. The system uses an IR beacon and a microcontroller receiver/controller module. The design consists of a field programmable gate array (FPGA) based IR transmitter and a microcontroller based IR receiver/controller. The design consisted of two main parts, the transmitter (beacon) and the receiver/controller module. The receiver was implemented with a FPGA so that the characteristics of the beacon signal could be adjusted more quickly and with greater precision. The controller module was integrated with the receivers and detailed system integration tests were performed. Measurements were collected, recorded and analyzed.

  1. Cerebral autoregulation with changes in arterial and cerebral venous pressure

    SciTech Connect

    McPherson, R.W.; Traystman, R.J.

    1986-03-01

    The effect of cerebral venous pressure (Pcv) elevation on cerebral autoregulation has been incompletely studied. The authors compared the effect of decreased cerebral perfusion pressure (CPP) by elevated Pcv and decreased arterial pressure (Pa) on cerebral blood flow (CBF) in a canine modified bypass model. CPP of 80, 70, 60, 50, 40 and 30 mmHg were produced by decreasing Pa with intracranial pressure (ICP) and Pcv maintained at 0 mmHg (group 1, n = 5), or by elevating Pcv as Pa was maintained at 80 mmHg (group 2, n = 5. CBF was measured using radiolabeled microspheres, and CMRO/sub 2/ = CBF times arterial-sagittal sinus O/sub 2/ content difference. Cerebrovascular resistance (CVR) = CPP/CBF. In group 1 CBF (ml/100 gm/min) was unchanged from control (36 +/- 4) as CPP was decreased from 80 to 40 mmHg. As CPP was decreased to 30 mmHg, CBF decreased to 28 +/- 1. CVR (mmHg/ml/min/100 gm) was 2.3 +/- 0.3 and progressively decreased to 1.0 +/- 0.1 at CPP of 30 mmHg. In group 2 CBF was 34 +/- 3 and was unchanged as CPP decreased to 50 mmHg. At CPP of 40 and 30 mmHg CBF decreased to 25 +/- 3 and 22 +/- 2 respectively. Control CRV was 2.4 +/- 0.2 and progressively decreased to 1.4 +/- 0.1 as CPP decreased to 30 mmHg. CMRO/sub 2/ was unchanged from control in both groups. Thus, CBF is maintained to low CPP regardless of whether vascular transmural pressure was decreased (decrease Pa) or increased (increased Pcv) demonstrating that the myogenic mechanism of autoregulation may be unimportant in normoxic dogs.

  2. What's new in cerebral palsy.

    PubMed

    JONES, M H

    1953-11-01

    Among new researches bearing on cerebral palsy are the growth of brain cells in tissue cultures for experimentation; the use of polysaccharides to prevent the formation of a glial barrier to nerve growth after injury; observation of changes in reactions of neurons at various stages of development; the finding of hypernatremia and hyperchloremia in lesions of the frontal lobe and the thalamus; stimulation of cerebral blood flow by injection of sodium bicarbonate and retardation with ammonium chloride; and studies of serial sections of brains of palsied children who died. Study of development in the early months of life has made possible the detection of significant abnormalities in behavior early in life. Loss of hearing may be tested in very young children by measuring minute variations in electrical resistance of the skin upon auditory stimulation of the sympathetic nervous system. Conditions which have been described as having been confused with cerebral palsy are dislocation of a cervical vertebra, hereditary spastic paraplegia, transverse myelopathy, injury to the spinal cord or cauda equina by anomalous growths of the spine, and also encephalitis and meningitis. Sedation has proved a valuable adjunct to electroencephalographic study of cerebral palsy. Better criteria for abnormality in the young child should be determined and the application of them more clearly standardized. Simple exercises are useful for early training of palsied children to stimulate development. "Crossed laterality"-the dominant eye being contralateral to the preferred hand-has been counteracted by special training with great success in eliminating emotional and behavior problems and accelerating development.Recent studies indicate that only 50 per cent of cerebral palsy patients have normal or better intelligence. Subluxation of the hip joint, a common deformity associated with cerebral palsy, can sometimes be corrected by operation if detected at an early stage. Radical ablation of

  3. [Etiologies of cerebral palsy and classical treatment possibilities].

    PubMed

    Maurer, Ute

    2002-01-01

    Cerebral palsy is a non-progressive disorder of the developing brain with different etiologies in the pre-, peri- or postnatal period. The most important of these diseases is cystic periventricular leukomalacia (PVL), followed by intra- and periventricular hemorrhage, hypoxic-ischemic encephalopathy, vascular disorders, infections or brain malformations. The underlying cause is always a damage of the first motor neuron. Prevalence of cerebral palsy in Europe is 2-3 per 1000 live births with a broad spectrum in different birth weight groups. Our own data concerning only pre-term infants in the NICU with birth weight below 1500 g (VLBW) are between 10%-20%. Established classical treatment methods include physiotherapy (Bobath, Vojta, Hippotherapy), methods of speech and occupational therapists (Castillo-Morales, Sensory Integration) and other therapeutical concepts (Petö, Affolter, Frostig). PMID:11862678

  4. Mapping the Structural Core of Human Cerebral Cortex

    PubMed Central

    Hagmann, Patric; Cammoun, Leila; Gigandet, Xavier; Meuli, Reto; Honey, Christopher J; Wedeen, Van J; Sporns, Olaf

    2008-01-01

    Structurally segregated and functionally specialized regions of the human cerebral cortex are interconnected by a dense network of cortico-cortical axonal pathways. By using diffusion spectrum imaging, we noninvasively mapped these pathways within and across cortical hemispheres in individual human participants. An analysis of the resulting large-scale structural brain networks reveals a structural core within posterior medial and parietal cerebral cortex, as well as several distinct temporal and frontal modules. Brain regions within the structural core share high degree, strength, and betweenness centrality, and they constitute connector hubs that link all major structural modules. The structural core contains brain regions that form the posterior components of the human default network. Looking both within and outside of core regions, we observed a substantial correspondence between structural connectivity and resting-state functional connectivity measured in the same participants. The spatial and topological centrality of the core within cortex suggests an important role in functional integration. PMID:18597554

  5. CEREBRAL PALSY. PRENTICE-HALL FOUNDATIONS OF SPEECH PATHOLOGY SERIES.

    ERIC Educational Resources Information Center

    CHANCE, BURTON, JR.; MCDONALD, EUGENE T.

    THIS INTRODUCTORY TEXT ON CEREBRAL PALSY IS DIVIDED INTO TWO SECTIONS. THE FIRST SECTION OF THE BOOK CONTAINS INFORMATION ABOUT UNDERSTANDING THE MEANING OF CEREBRAL PALSY, PROGRAMS FOR THOSE WITH CEREBRAL PALSY, THE NEUROLOGICAL BASES, ETIOLOGY, AND DIAGNOSIS, AND THE CLASSIFICATION OF CEREBRAL PALSY. PROBLEMS OFTEN ASSOCIATED WITH CEREBRAL PALSY…

  6. Extrapolating target tracks

    NASA Astrophysics Data System (ADS)

    Van Zandt, James R.

    2012-05-01

    Steady-state performance of a tracking filter is traditionally evaluated immediately after a track update. However, there is commonly a further delay (e.g., processing and communications latency) before the tracks can actually be used. We analyze the accuracy of extrapolated target tracks for four tracking filters: Kalman filter with the Singer maneuver model and worst-case correlation time, with piecewise constant white acceleration, and with continuous white acceleration, and the reduced state filter proposed by Mookerjee and Reifler.1, 2 Performance evaluation of a tracking filter is significantly simplified by appropriate normalization. For the Kalman filter with the Singer maneuver model, the steady-state RMS error immediately after an update depends on only two dimensionless parameters.3 By assuming a worst case value of target acceleration correlation time, we reduce this to a single parameter without significantly changing the filter performance (within a few percent for air tracking).4 With this simplification, we find for all four filters that the RMS errors for the extrapolated state are functions of only two dimensionless parameters. We provide simple analytic approximations in each case.

  7. [Cerebral syndromes in premature children].

    PubMed

    Edel'shteĭn, E A; Bandarenko, E S

    1983-01-01

    Cerebral disturbances observed in premature infants are analyzed. These disturbances are a consequence of developmental slowdown and are associated with the pathological immaturity of the brain structures. On condition an active pathogenetic therapy is given these disturbances may gradually regress. On the basis of long-term observations of 600 prematurely born infants the authors describe the following clinical syndromes: muscular hypotonicity lasting up to 4-5 months and followed with a rise of the tone; the syndrome of "paretic hands" observed during the first two months of life; a hypertensive-hydrocephalic syndrome combined with a rise of the neuro-reflectory excitability; the syndrome of psychomotor development retardation followed at an age of over 1.5 to 2 years by complete recovery or minimal cerebral insufficiency with belated development of motor speech and neurosis-like reactions. PMID:6880498

  8. Imaging of cerebral venous thrombosis.

    PubMed

    Bonneville, F

    2014-12-01

    Cerebral venous thrombosis (CVT) is a potentially life-threatening emergency. The wide ranging of clinical symptoms makes the use of imaging in "slices" even more important for diagnosis. Both CT and MRI are used to diagnose the occlusion of a venous sinus, but MRI is superior to CT for detecting a clot in the cortical or deep veins. CT can show the hyperintense clot spontaneously and CT angiography the intraluminal defect. MRI also detects this thrombus, whose signal varies over time: in the acute phase, it is hypointense in T2*, whilst T1 and T2 can appear falsely reassuring; in the subacute phase, it is hyperintense on all sequences (T1, T2, FLAIR, T2*, diffusion). MRI easily shows the ischemic damage, even hemorrhagic, in the cerebral parenchyma in cases of CVT. Finally, imaging may reveal pathology at the origin of the CVT, such as a fracture of the skull, infection, tumor, dural fistula, or intracranial hypotension. PMID:25465119

  9. Animal models of cerebral ischemia

    NASA Astrophysics Data System (ADS)

    Khodanovich, M. Yu.; Kisel, A. A.

    2015-11-01

    Cerebral ischemia remains one of the most frequent causes of death and disability worldwide. Animal models are necessary to understand complex molecular mechanisms of brain damage as well as for the development of new therapies for stroke. This review considers a certain range of animal models of cerebral ischemia, including several types of focal and global ischemia. Since animal models vary in specificity for the human disease which they reproduce, the complexity of surgery, infarct size, reliability of reproduction for statistical analysis, and adequate models need to be chosen according to the aim of a study. The reproduction of a particular animal model needs to be evaluated using appropriate tools, including the behavioral assessment of injury and non-invasive and post-mortem control of brain damage. These problems also have been summarized in the review.

  10. [Cerebral artery thrombosis in pregnancy].

    PubMed

    Charco Roca, L M; Ortiz Sanchez, V E; Hernandez Gutierrez-Manchon, O; Quesada Villar, J; Bonmatí García, L; Rubio Postigo, G

    2015-11-01

    A 28 year old woman, ASA I, who, in the final stages of her pregnancy presented with signs of neural deficit that consisted of distortion of the oral commissure, dysphagia, dysarthria, and weakness on the left side of the body. She was diagnosed with thrombosis in a segment of the right middle cerebral artery which led to an ischemic area in the right frontal lobe. Termination of pregnancy and conservative treatment was decided, with good resolution of the symptoms. PMID:25698610

  11. Bilateral posterior cerebral artery infarction.

    PubMed

    Ryan, Davinia; Murphy, Sinead M; Hennessey, Michael J

    2010-01-01

    We report the case of a 70-year-old man who presented with short-term memory impairment and a homonymous left inferior quadrantanopia secondary to simultaneous bilateral posterior cerebral artery (PCA) territory infarction. As in more than a quarter of cases of PCA infarction, no aetiological cause was identified. Unlike the transient nature of symptoms in some cases following unilateral infarction, his deficits persisted on 2-month follow-up. PMID:22798298

  12. [Pathogenesis of infantile cerebral palsy].

    PubMed

    Semenova, K A

    1980-01-01

    Some causes of the pathological activity of postural reflexes and other motor disturbances underlying the clinical picture of infantile cerebral paralysis are considered. It is shown that disturbed metabolism of corticosteroids observed in that disease, as well as impaired functional activity of T lymphocytes promote the development of both inflammatory and neuroimmune processes in the brain, mainly in large hemispheres--and this may be one of the causes of the pathological postural activity. PMID:6969015

  13. Incidental Cerebral Microbleeds and Cerebral Blood Flow in Elderly Individuals

    PubMed Central

    Gregg, Nicholas M.; Kim, Albert E.; Gurol, M. Edip; Lopez, Oscar L.; Aizenstein, Howard J.; Price, Julie C.; Mathis, Chester A.; James, Jeffrey A.; Snitz, Beth E.; Cohen, Ann D.; Kamboh, M. Ilyas; Minhas, Davneet; Weissfeld, Lisa A.; Tamburo, Erica L.; Klunk, William E.

    2016-01-01

    IMPORTANCE Cerebral microbleeds (CMBs) are collections of blood breakdown products that are a common incidental finding in magnetic resonance imaging of elderly individuals. Cerebral microbleeds are associated with cognitive deficits, but the mechanism is unclear. Studies show that individuals with CMBs related to symptomatic cerebral amyloid angiopathy have abnormal vascular reactivity and cerebral blood flow (CBF), but, to our knowledge, abnormalities in cerebral blood flow have not been reported for healthy individuals with incidental CMBs. OBJECTIVE To evaluate the association of incidental CMBs with resting-state CBF, cerebral metabolism, cerebrovascular disease, β-amyloid (Aβ), and cognition. DESIGN, SETTING, AND PARTICIPANTS A cross-sectional study of 55 cognitively normal individuals with a mean (SD) age of 86.8 (2.7) years was conducted from May 1, 2010, to May 1, 2013, in an academic medical center in Pittsburgh; data analysis was performed between June 10, 2013, and April 9, 2015. INTERVENTIONS 3-Tesla magnetic resonance imaging was performed with susceptibility-weighted imaging or gradient-recalled echo to assess CMBs, arterial spin labeling for CBF, and T1- and T2-weighted imaging for atrophy, white matter hyperintensities, and infarcts. Positron emission tomography was conducted with fluorodeoxyglucose to measure cerebral metabolism and Pittsburgh compound B for fibrillar Aβ. Neuropsychological evaluation, including the Clinical Dementia Rating scale, was performed. MAIN OUTCOMES AND MEASURES Magnetic resonance images were rated for the presence and location of CMBs. Lobar CMBs were subclassified as cortical or subcortical. Measurements of CBF, metabolism, and Aβ were compared with the presence and number of CMBs with voxelwise and region-of-interest analyses. RESULTS The presence of cortical CMBs was associated with significantly reduced CBF in multiple regions on voxelwise and region-of-interest analyses (percentage difference in global CBF,

  14. UCSC Data Integrator and Variant Annotation Integrator

    PubMed Central

    Hinrichs, Angie S.; Raney, Brian J.; Speir, Matthew L.; Rhead, Brooke; Casper, Jonathan; Karolchik, Donna; Kuhn, Robert M.; Rosenbloom, Kate R.; Zweig, Ann S.; Haussler, David; Kent, W. James

    2016-01-01

    Summary: Two new tools on the UCSC Genome Browser web site provide improved ways of combining information from multiple datasets, optionally including the user's own custom track data and/or data from track hubs. The Data Integrator combines columns from multiple data tracks, showing all items from the first track along with overlapping items from the other tracks. The Variant Annotation Integrator is tailored to adding functional annotations to variant calls; it offers a more restricted set of underlying data tracks but adds predictions of each variant's consequences for any overlapping or nearby gene transcript. When available, it optionally adds additional annotations including effect prediction scores from dbNSFP for missense mutations, ENCODE regulatory summary tracks and conservation scores. Availability and implementation: The web tools are freely available at http://genome.ucsc.edu/ and the underlying database is available for download at http://hgdownload.cse.ucsc.edu/. The software (written in C and Javascript) is available from https://genome-store.ucsc.edu/ and is freely available for academic and non-profit usage; commercial users must obtain a license. Contact: angie@soe.ucsc.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26740527

  15. Cerebral ischaemia: A neuroradiological study

    SciTech Connect

    Bories, J.

    1985-01-01

    After a brief clinical and pathophysiological approach, the papers presented in this book are devoted to CT and angiography. Concerning CT, a particular study has been made of cerebral arterial territories on cuts parallel to the orbito-meatal line: these are very important in making the differential diagnosis from some tumors. Also concerning CT, a paper has been devoted to cerebral ''lacunae.'' The term ''lacuna'' as far as CT imaging is concerned, should be reserved only for those hypodense areas corresponding to small cavities containing fluid, which are sequelae of infarcts in the territory of penetrating arteries. Before this sequellar state come all the evolutive states of a small deep infarct. The angiographic study specifies the indications of angiography in the study of cerebral ischemia, and the techniques to be used. It shows the main etiologic aspects. Because of the important place of vascular surgery today, it seemed necessary to show also the main post operative angiographic aspects. After CT and angiography, some pages are reserved to more modern techniques. Finally, some pages are devoted to certain particular associations and etiologies: childhood, cardiopathies, migraine, oral contraception and end with venous infarction.

  16. Bone age in cerebral palsy

    PubMed Central

    Miranda, Eduardo Régis de Alencar Bona; Palmieri, Maurício D'arc; de Assumpção, Rodrigo Montezuma César; Yamada, Helder Henzo; Rancan, Daniela Regina; Fucs, Patrícia Maria de Moraes Barros

    2013-01-01

    Objective To compare the chronological age and bone age among cerebral palsy patients in the outpatient clinic and its correlation with the type of neurological involvement, gender and functional status. Methods 401 patients with spastic cerebral palsy, and ages ranging from three months to 20 years old, submitted to radiological examination for bone age and analyzed by two independent observers according Greulich & Pyle. Results In the topographic distribution, there was a significant delay (p<0.005) in tetraparetic (17.7 months), hemiparetic (10.1 months), and diparetic patients (7.9 months). In the hemiparetic group, the mean bone age in the affected side was 96.88 months and the uncompromised side was 101.13 months (p<0.005). Regarding functional status, the ambulatory group showed a delay of 18.73 months in bone age (p<0.005). Comparing bone age between genders, it was observed a greater delay in males (13.59 months) than in females (9.63 months), but not statistically significant (p = 0.54). Conclusion There is a delay in bone age compared to chronological age influenced by the topography of spasticity, functional level and gender in patients with cerebral palsy. Level of Evidence IV, Case Series. PMID:24453693

  17. Maximum power tracking

    SciTech Connect

    O'Sullivan, G.

    1983-03-01

    By definition, a maximum power tracking device causes the photovoltaic array to operate on the locus of maximum power points within a specified accuracy. There are limitations to the application of maximum power tracking. A prerequisite is that the load be capable of absorbing all of the power availble at all times. Battery chargers, electrical heaters, water pumps, and most significantly, returning power to the utility grid, are prime examples of applications that are adaptable to maximum power tracking. Maximum power tracking is available to either dc or ac loads. An inverter equipped with a means of changing input voltage by controlling its input impedance can deliver maximum power to ac loads. The inverter can be fixed or variable frequency and fixed or variable voltage, but must be compatible with the ac load. The discussion includes applications, techniques, and cost factors.

  18. Enhanced optical tracking

    NASA Astrophysics Data System (ADS)

    McSheery, Tracy

    2008-04-01

    Enhanced tracking is accomplished by increasing the resolution, frame rate and processing capabilities in tracking dynamic regions of interest for vision applications. In many proven algorithms, the ability to distinguish an object and track it is dependent on the system performance in more than one attribute. We have conducted studies on proven techniques such as Active Appearance Models, Principle Component Analysis and Eigen tracking. All perform better as the camera resolution increases, and camera frame rate increases. Additional opportunities have been observed by combining these techniques, taking advantage of Multicore CPUs, and GPU graphic card processing. Results from an 8 Megapixel commercial sensor combined with a Field Programmable Gate array are presented, and algorithm performance compared with down scaled images of the same scenes, and simulated typical 30 hertz frame rates verses the 120 hertz to 300 hertz typical of this smart camera.

  19. Energy Tracking Software Platform

    SciTech Connect

    Ryan Davis; Nathan Bird; Rebecca Birx; Hal Knowles

    2011-04-04

    Acceleration has created an interactive energy tracking and visualization platform that supports decreasing electric, water, and gas usage. Homeowners have access to tools that allow them to gauge their use and track progress toward a smaller energy footprint. Real estate agents have access to consumption data, allowing for sharing a comparison with potential home buyers. Home builders have the opportunity to compare their neighborhood's energy efficiency with competitors. Home energy raters have a tool for gauging the progress of their clients after efficiency changes. And, social groups are able to help encourage members to reduce their energy bills and help their environment. EnergyIT.com is the business umbrella for all energy tracking solutions and is designed to provide information about our energy tracking software and promote sales. CompareAndConserve.com (Gainesville-Green.com) helps homeowners conserve energy through education and competition. ToolsForTenants.com helps renters factor energy usage into their housing decisions.

  20. Cerebral Palsy. Fact Sheet = La Paralisis Cerebral. Hojas Informativas Sobre Discapacidades.

    ERIC Educational Resources Information Center

    National Information Center for Children and Youth with Disabilities, Washington, DC.

    This fact sheet on cerebral palsy is written in both English and Spanish. First, it provides a definition of cerebral palsy and considers various causes (e.g., an insufficient amount of oxygen reaching the fetal or newborn brain). The fact sheet then offers incidence figures and explains characteristics of the three main types of cerebral palsy:…

  1. Advanced Doppler tracking experiments

    NASA Technical Reports Server (NTRS)

    Armstrong, J. W.

    1989-01-01

    The Doppler tracking method is currently the only technique available for broadband gravitational wave searches in the approx. 10(exp -4) to 10(exp -1) Hz low frequency band. A brief review is given of the Doppler method, a discussion of the main noise sources, and a review of experience with current spacecraft and the prospects for sensitivity improvements in an advanced Doppler tracking experiment.

  2. Effects of captopril on cerebral blood flow in normotensive and hypertensive rats

    SciTech Connect

    Barry, D.I.; Paulson, O.B.; Jarden, J.O.; Juhler, M.; Graham, D.I.; Strandgaard, S.

    1984-05-31

    Cerebrovascular effects of the angiotensin converting enzyme inhibitor captopril were examined in normotensive and hypertensive rats. Cerebral blood flow was measured with the intracarotid /sup 133/xenon injection method in halothane-anesthetized animals. The blood-brain barrier permeability of captopril (determined with an integral-uptake method) was negligible, the permeability-surface area product in most brain regions being 1 X 10(-5) cm3/g per second, that is, three to four times lower than that of sodium ion. When administered into the cerebral ventricles to bypass the blood-brain barrier, captopril had no effect on cerebral blood flow: furthermore, cerebral blood flow autoregulation (studied by raising and lowering blood pressure) was identical to that in controls. In contrast, when given intravenously, captopril had a marked effect on cerebral blood flow autoregulation--both the lower and upper limits of autoregulation being shifted to a lower pressure (by about 20 to 30 and 50 to 60 mm Hg, respectively), and the autoregulatory range was shortened by about 40 mm Hg. This effect may be ascribed to inhibition of converting enzyme in the cerebral blood vessels rather than within the brain.

  3. Parasympathetic tonic dilatory influences on cerebral vessels.

    PubMed

    Boysen, Nicholas C; Dragon, Deidre Nitschke; Talman, William T

    2009-05-11

    Parasympathetic nerves from the pterygopalatine ganglia may participate in development of cluster headaches, in vascular responses to hypertension and in modulation of damage due to stroke. Stimulation of the nerves elicits cerebral vasodilatation, but it is not known if the nerves tonically influence cerebrovascular tone. We hypothesized that parasympathetics provide a tonic vasodilator influence and tested that hypothesis by measuring cerebral blood flow in anesthetized rats before and after removal of a pterygopalatine ganglion. Ganglion removal led to reduced cerebral blood flow without changing blood pressure. Thus, parasympathetic nerves provide tonic vasodilatory input to cerebral blood vessels. PMID:19195933

  4. NorTRACK TM product tracking system—development and implementation

    NASA Astrophysics Data System (ADS)

    Gibson, W.; Veselovsky, P.

    1999-06-01

    This paper presents the experience gained by developers and users with implementation and operation of NorTRACK TM, a real-time computerized product tracking system. A Programmable Logic Controller (PLC) collects and transfers data in real time to NorTRACK's Oracle TM database on a Windows NT TM server network. After extensive development and Beta testing at MDS Nordion's Canadian Irradiation Centre in Montreal, Canada, NorTRACK was installed in January 1997 with a new irradiation facility in Ethicon Endo-Surgery Inc.'s Albuquerque plant in the United States. NorTRACK communicates with the irradiator control and safety system, the plant's central manufacturing database, an innovative pallet staging and tote loading robot, and an automated dosimetry reading system. This integrated system allows the sterilization facility to monitor the irradiator operation and the flow of many products, through varied processing modes, continuously and reliably. As a result of operating with NorTRACK, both MDS Nordion's CIC facility and the Endo-Surgery manufacturing site, are beginning to realize unique benefits in their respective operations. MDS Nordion is also initiating several future product enhancements and additional productivity modules. This paper describes the NorTRACK system, the various stages of the development project and Beta tests, and the experience of the users to date in their operations.

  5. Optimal modified tracking performance for MIMO systems under bandwidth constraint.

    PubMed

    Sun, Xin-Xiang; Wu, Jie; Zhan, Xi-Sheng; Han, Tao

    2016-05-01

    This paper investigates the optimal modified tracking performance of multi-input multi-output (MIMO) networked control systems (NCSs) with bandwidth and channel noise constraints. A new modified tracking performance index is proposed which prevents variations in the tracking error from leading to invalid data where there is no integrator in the plant. An expression for the optimal modified tracking performance is obtained using a method which includes co-prime factorization, partial factorization, spectral decomposition and H2 norm. The obtained results show that the optimal modified tracking performance is influenced by the non-minimum phase (NMP) zeros, unstable poles, and their directions. Furthermore, the characteristics of the input signal, the modification factor, the bandwidth and the channel noise are also shown to be closely related to the optimal modified tracking performance. Finally, the efficiency of the result is verified using some typical examples. PMID:26874745

  6. Nanoscale Phase Transitions under Extreme Conditions within an Ion Track

    SciTech Connect

    Zhang, Jiaming; Lang, Maik; Ewing, Rodney C.; Devanathan, R.; Weber, William; Toulemonde, M.

    2011-01-31

    The dynamics of track development due to the passage of relativistic heavy ions through solids is a long-standing issue relevant to nuclear materials, age dating of minerals, space exploration, and nanoscale fabrication of novel devices. We have integrated experimental and simulation approaches to investigate nanoscale phase transitions under the extreme conditions created within single tracks of relativistic ions in Gd{sub 2}O{sub 3}(TiO{sub 2}){sub x} and Gd{sub 2}Zr{sub 2–x} Ti{sub x} O{sub 7}. Track size and internal structure depend on energy density deposition, irradiation temperature, and material composition. Based on the inelastic thermal spike model, molecular dynamics simulations follow the time evolution of individual tracks and reveal the phase transition pathways to the concentric track structures observed experimentally. Individual ion tracks have nanoscale core-shell structures that provide a unique record of the phase transition pathways under extreme conditions.

  7. Joint tracking, pose estimation, and identification using HRRR data

    NASA Astrophysics Data System (ADS)

    Mahler, Ronald P. S.; Rago, Constantino; Zajic, Tim; Musick, Stanton; Mehra, Raman K.

    2000-08-01

    The work presented here is pat of a generalization of Bayesian filtering and estimation theory to the problem of multisource, multitarget, multi-evidence unified joint detection, tracking, and target ID developed by Lockheed Martin Tactical Defense Systems and Scientific Systems Co., Inc. Our approach to robust joint target identification and tracking was to take the StaF algorithm and integrate it with a Bayesian nonlinear filter, where target position, velocity, pose, and type could then be determined simultaneously via maximum a posteriori estimation. The basis for the integration between the tracker and classifier is base don 'finite-set statistics' (FISST). The theoretical development of FISST is a Lockheed Martin ongoing project since 1994. The specific problem addressed in this paper is that of robust joint target identification and tracking via fusion of high range resolution radar (HRRR) - from the automatic radar target identification (ARTI) data base - signatures and radar track data. A major problem in HRRR ATR is the computational load created by having to match observations against target models for every feasible pose. If pose could be estimated efficiently by a filtering algorithm from track data, the ATR search space would be greatly reduced. On the other hand, HRRR ATR algorithms produce useful information about pose which could potentially aid the track-filtering process as well. We have successfully demonstrated the former concept of 'loose integration' integrating the tracker and classifier for three different type of targets moving on 2D tracks.

  8. WIPP Transparency Project - container tracking and monitoring demonstration using the Authenticated Tracking and Monitoring System (ATMS)

    SciTech Connect

    SCHOENEMAN, J. LEE; SMARTT, HEIDI ANNE; HOFER, DENNIS

    2000-01-27

    The Authenticated Tracking and Monitoring System (ATMS) is designed to answer the need for global monitoring of the status and location of proliferation-sensitive items on a worldwide basis, 24 hours a day. ATMS uses wireless sensor packs to monitor the status of the items within the shipment and surrounding environmental conditions. Receiver and processing units collect a variety of sensor event data that is integrated with GPS tracking data. The collected data are transmitted to the International Maritime Satellite (INMARSAT) communication system, which then sends the data to mobile ground stations. Authentication and encryption algorithms secure the data during communication activities. A typical ATMS application would be to track and monitor the stiety and security of a number of items in transit along a scheduled shipping route. The resulting tracking, timing, and status information could then be processed to ensure compliance with various agreements.

  9. Assessing cerebral autoregulation via oscillatory lower body negative pressure and projection pursuit regression.

    PubMed

    Taylor, J Andrew; Tan, Can Ozan; Hamner, J W

    2014-01-01

    The process by which cerebral perfusion is maintained constant over a wide range of systemic pressures is known as "cerebral autoregulation." Effective dampening of flow against pressure changes occurs over periods as short as ~15 sec and becomes progressively greater over longer time periods. Thus, slower changes in blood pressure are effectively blunted and faster changes or fluctuations pass through to cerebral blood flow relatively unaffected. The primary difficulty in characterizing the frequency dependence of cerebral autoregulation is the lack of prominent spontaneous fluctuations in arterial pressure around the frequencies of interest (less than ~0.07 Hz or ~15 sec). Oscillatory lower body negative pressure (OLBNP) can be employed to generate oscillations in central venous return that result in arterial pressure fluctuations at the frequency of OLBNP. Moreover, Projection Pursuit Regression (PPR) provides a nonparametric method to characterize nonlinear relations inherent in the system without a priori assumptions and reveals the characteristic non-linearity of cerebral autoregulation. OLBNP generates larger fluctuations in arterial pressure as the frequency of negative pressure oscillations become slower; however, fluctuations in cerebral blood flow become progressively lesser. Hence, the PPR shows an increasingly more prominent autoregulatory region at OLBNP frequencies of 0.05 Hz and below (20 sec cycles). The goal of this approach it to allow laboratory-based determination of the characteristic nonlinear relationship between pressure and cerebral flow and could provide unique insight to integrated cerebrovascular control as well as to physiological alterations underlying impaired cerebral autoregulation (e.g., after traumatic brain injury, stroke, etc.). PMID:25549201

  10. Unified detection and tracking of instruments during retinal microsurgery.

    PubMed

    Sznitman, Raphael; Richa, Rogerio; Taylor, Russell H; Jedynak, Bruno; Hager, Gregory D

    2013-05-01

    Methods for tracking an object have generally fallen into two groups: tracking by detection and tracking through local optimization. The advantage of detection-based tracking is its ability to deal with target appearance and disappearance, but it does not naturally take advantage of target motion continuity during detection. The advantage of local optimization is efficiency and accuracy, but it requires additional algorithms to initialize tracking when the target is lost. To bridge these two approaches, we propose a framework for unified detection and tracking as a time-series Bayesian estimation problem. The basis of our approach is to treat both detection and tracking as a sequential entropy minimization problem, where the goal is to determine the parameters describing a target in each frame. To do this we integrate the Active Testing (AT) paradigm with Bayesian filtering, and this results in a framework capable of both detecting and tracking robustly in situations where the target object enters and leaves the field of view regularly. We demonstrate our approach on a retinal tool tracking problem and show through extensive experiments that our method provides an efficient and robust tracking solution. PMID:23520263

  11. Summary of tracking and identification methods

    NASA Astrophysics Data System (ADS)

    Blasch, Erik; Yang, Chun; Kadar, Ivan

    2014-06-01

    Over the last two decades, many solutions have arisen to combine target tracking estimation with classification methods. Target tracking includes developments from linear to non-linear and Gaussian to non-Gaussian processing. Pattern recognition includes detection, classification, recognition, and identification methods. Integrating tracking and pattern recognition has resulted in numerous approaches and this paper seeks to organize the various approaches. We discuss the terminology so as to have a common framework for various standards such as the NATO STANAG 4162 - Identification Data Combining Process. In a use case, we provide a comparative example highlighting that location information (as an example) with additional mission objectives from geographical, human, social, cultural, and behavioral modeling is needed to determine identification as classification alone does not allow determining identification or intent.

  12. CMOS imager for pointing and tracking applications

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata (Inventor); Sun, Chao (Inventor); Yang, Guang (Inventor); Heynssens, Julie B. (Inventor)

    2006-01-01

    Systems and techniques to realize pointing and tracking applications with CMOS imaging devices. In general, in one implementation, the technique includes: sampling multiple rows and multiple columns of an active pixel sensor array into a memory array (e.g., an on-chip memory array), and reading out the multiple rows and multiple columns sampled in the memory array to provide image data with reduced motion artifact. Various operation modes may be provided, including TDS, CDS, CQS, a tracking mode to read out multiple windows, and/or a mode employing a sample-first-read-later readout scheme. The tracking mode can take advantage of a diagonal switch array. The diagonal switch array, the active pixel sensor array and the memory array can be integrated onto a single imager chip with a controller. This imager device can be part of a larger imaging system for both space-based applications and terrestrial applications.

  13. Tracking accuracy assessment for concentrator photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Norton, Matthew S. H.; Anstey, Ben; Bentley, Roger W.; Georghiou, George E.

    2010-10-01

    The accuracy to which a concentrator photovoltaic (CPV) system can track the sun is an important parameter that influences a number of measurements that indicate the performance efficiency of the system. This paper presents work carried out into determining the tracking accuracy of a CPV system, and illustrates the steps involved in gaining an understanding of the tracking accuracy. A Trac-Stat SL1 accuracy monitor has been used in the determination of pointing accuracy and has been integrated into the outdoor CPV module test facility at the Photovoltaic Technology Laboratories in Nicosia, Cyprus. Results from this work are provided to demonstrate how important performance indicators may be presented, and how the reliability of results is improved through the deployment of such accuracy monitors. Finally, recommendations on the use of such sensors are provided as a means to improve the interpretation of real outdoor performance.

  14. Blood flow distribution in cerebral arteries

    PubMed Central

    Zarrinkoob, Laleh; Ambarki, Khalid; Wåhlin, Anders; Birgander, Richard; Eklund, Anders; Malm, Jan

    2015-01-01

    High-resolution phase–contrast magnetic resonance imaging can now assess flow in proximal and distal cerebral arteries. The aim of this study was to describe how total cerebral blood flow (tCBF) is distributed into the vascular tree with regard to age, sex and anatomic variations. Forty-nine healthy young (mean 25 years) and 45 elderly (mean 71 years) individuals were included. Blood flow rate (BFR) in 21 intra- and extracerebral arteries was measured. Total cerebral blood flow was defined as BFR in the internal carotid plus vertebral arteries and mean cerebral perfusion as tCBF/brain volume. Carotid/vertebral distribution was 72%/28% and was not related to age, sex, or brain volume. Total cerebral blood flow (717±123 mL/min) was distributed to each side as follows: middle cerebral artery (MCA), 21% distal MCA, 6% anterior cerebral artery (ACA), 12%, distal ACA, 4% ophthalmic artery, 2% posterior cerebral artery (PCA), 8% and 20% to basilar artery. Deviating distributions were observed in subjects with ‘fetal' PCA. Blood flow rate in cerebral arteries decreased with increasing age (P<0.05) but not in extracerebral arteries. Mean cerebral perfusion was higher in women (women: 61±8; men: 55±6 mL/min/100 mL, P<0.001). The study describes a new method to outline the flow profile of the cerebral vascular tree, including reference values, and should be used for grading the collateral flow system. PMID:25564234

  15. OCULUS Sea Track Fusion Service

    NASA Astrophysics Data System (ADS)

    Panagiotou, Stylianos C.; Rizogiannis, Constantinos; Katsoulis, Stavros; Lampropoulos, Vassilis; Kanellopoulos, Sotirios; Thomopoulos, Stelios C. A.

    2015-06-01

    Oculus Sea is a complete solution regarding maritime surveillance and communications at Local as well as Central Command and Control level. It includes a robust and independent track fusion service whose main functions include: 1) Interaction with the User to suggest the fusion of two or more tracks, confirm Track ID and Vessel Metadata creation for the fused track, and suggest de-association of two tracks 2) Fusion of same vessel tracks arriving simultaneously from multiple radar sensors featuring track Association, track Fusion of associated tracks to produce a more accurate track, and Multiple tracking filters and fusion algorithms 3) Unique Track ID Generator for each fused track 4) Track Dissemination Service. Oculus Sea Track Fusion Service adopts a system architecture where each sensor is associated with a Kalman estimator/tracker that obtains an estimate of the state vector and its respective error covariance matrix. Finally, at the fusion center, association and track state estimation fusion are carried out. The expected benefits of this system include multi-sensor information fusion, enhanced spatial resolution, and improved target detection.

  16. Cerebral Microbleeds: A Review of Clinical, Genetic, and Neuroimaging Associations

    PubMed Central

    Yates, Paul A.; Villemagne, Victor L.; Ellis, Kathryn A.; Desmond, Patricia M.; Masters, Colin L.; Rowe, Christopher C.

    2013-01-01

    Cerebral microbleeds (microbleeds) are small, punctuate hypointense lesions seen in T2* Gradient-Recall Echo (GRE) and Susceptibility-Weighted (SWI) Magnetic Resonance Imaging (MRI) sequences, corresponding to areas of hemosiderin breakdown products from prior microscopic hemorrhages. They occur in the setting of impaired small vessel integrity, commonly due to either hypertensive vasculopathy or cerebral amyloid angiopathy. Microbleeds are more prevalent in individuals with Alzheimer’s disease (AD) dementia and in those with both ischemic and hemorrhagic stroke. However they are also found in asymptomatic individuals, with increasing prevalence with age, particularly in carriers of the Apolipoprotein (APOE) ε4 allele. Other neuroimaging findings that have been linked with microbleeds include lacunar infarcts and white matter hyperintensities on MRI, and increased cerebral β-amyloid burden using 11C-PiB Positron Emission Tomography. The presence of microbleeds has been suggested to confer increased risk of incident intracerebral hemorrhage – particularly in the setting of anticoagulation – and of complications of immunotherapy for AD. Prospective data regarding the natural history and sequelae of microbleeds are currently limited, however there is a growing evidence base that will serve to inform clinical decision-making in the future. PMID:24432010

  17. Optical coherence Doppler tomography for quantitative cerebral blood flow imaging

    PubMed Central

    You, Jiang; Du, Congwu; Volkow, Nora D.; Pan, Yingtian

    2014-01-01

    Optical coherence Doppler tomography (ODT) is a promising neurotechnique that permits 3D imaging of the cerebral blood flow (CBF) network; however, quantitative CBF velocity (CBFv) imaging remains challenging. Here we present a simple phase summation method to enhance slow capillary flow detection sensitivity without sacrificing dynamic range for fast flow and vessel tracking to improve angle correction for absolute CBFv quantification. Flow phantom validation indicated that the CBFv quantification accuracy increased from 15% to 91% and the coefficient of variation (CV) decreased 9.3-fold; in vivo mouse brain validation showed that CV decreased 4.4-/10.8- fold for venular/arteriolar flows. ODT was able to identify cocaine-elicited microischemia and quantify CBFv disruption in branch vessels and capillaries that otherwise would have not been possible. PMID:25401033

  18. The Influence of Motor Impairment on Autonomic Heart Rate Modulation among Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Zamuner, Antonio Roberto; Cunha, Andrea Baraldi; da Silva, Ester; Negri, Ana Paola; Tudella, Eloisa; Moreno, Marlene Aparecida

    2011-01-01

    The study of heart rate variability is an important tool for a noninvasive evaluation of the neurocardiac integrity. The present study aims to evaluate the autonomic heart rate modulation in supine and standing positions in 12 children diagnosed with cerebral palsy and 16 children with typical motor development (control group), as well as to…

  19. Quality of Life of Adolescents with Cerebral Palsy: Perspectives of Adolescents and Parents

    ERIC Educational Resources Information Center

    Davis, Elise; Shelly, Amy; Waters, Elizabeth; MacKinnon, Andrew; Reddihough, Dinah; Boyd, Roslyn; Graham, H. Kerr

    2009-01-01

    Quality of life (QOL) has emerged over the past 20 years as an outcome for measuring the effectiveness of health-improvement interventions. The Cerebral Palsy Quality of Life Questionnaire for Children (CPQOL-Child) is well regarded and now integrated into research internationally. We describe the results of qualitative research, using grounded…

  20. Subaru FATS (fault tracking system)

    NASA Astrophysics Data System (ADS)

    Winegar, Tom W.; Noumaru, Junichi

    2000-07-01

    The Subaru Telescope requires a fault tracking system to record the problems and questions that staff experience during their work, and the solutions provided by technical experts to these problems and questions. The system records each fault and routes it to a pre-selected 'solution-provider' for each type of fault. The solution provider analyzes the fault and writes a solution that is routed back to the fault reporter and recorded in a 'knowledge-base' for future reference. The specifications of our fault tracking system were unique. (1) Dual language capacity -- Our staff speak both English and Japanese. Our contractors speak Japanese. (2) Heterogeneous computers -- Our computer workstations are a mixture of SPARCstations, Macintosh and Windows computers. (3) Integration with prime contractors -- Mitsubishi and Fujitsu are primary contractors in the construction of the telescope. In many cases, our 'experts' are our contractors. (4) Operator scheduling -- Our operators spend 50% of their work-month operating the telescope, the other 50% is spent working day shift at the base facility in Hilo, or day shift at the summit. We plan for 8 operators, with a frequent rotation. We need to keep all operators informed on the current status of all faults, no matter the operator's location.

  1. Hemodynamic Intervention of Cerebral Aneurysms

    NASA Astrophysics Data System (ADS)

    Meng, Hui

    2005-11-01

    Cerebral aneurysm is a pathological vascular response to hemodynamic stimuli. Endovascular treatment of cerebral aneurysms essentially alters the blood flow to stop them from continued growth and eventual rupture. Compared to surgical clipping, endovascular methods are minimally invasive and hence rapidly gaining popularity. However, they are not always effective with risks of aneurysm regrowth and various complications. We aim at developing a Virtual Intervention (VI) platform that allows: patient-specific flow calculation and risk prediction as well as recommendation of tailored intervention based on quantitative analysis. This is a lofty goal requiring advancement in three areas of research: (1). Advancement of image-based CFD; (2) Understanding the biological/pathological responses of tissue to hemodynamic factors in the context of cerebral aneurysms; and (3) Capability of designing and testing patient-specific endovascular devices. We have established CFD methodologies based on anatomical geometry obtained from 3D angiographic or CT images. To study the effect of hemodynamics on aneurysm development, we have created a canine model of a vascular bifurcation anastomosis to provide the hemodynamic environment similar to those in CA. Vascular remodeling was studied using histology and compared against the flow fields obtained from CFD. It was found that an intimal pad, similar to those frequently seen clinically, developed at the flow impingement site, bordering with an area of `groove' characteristic of an early stage of aneurysm, where the micro environment exhibits an elevated wall shear stresses. To further address the molecular mechanisms of the flow-mediated aneurysm pathology, we are also developing in vitro cell culture systems to complement the in vivo study. Our current effort in endovascular device development focuses on novel stents that alters the aneurysmal flow to promote thrombotic occlusion as well as favorable remodeling. Realization of an

  2. Magnetic Low-Friction Track

    NASA Astrophysics Data System (ADS)

    Paetkau, Mark; Bahniwal, Manpreet; Gamblen, James

    2008-05-01

    The standard low-friction tracks used to test Newton's laws are the air track and the low-friction cart track. Both are commercially available and provide low-friction environments to test various physics concepts. At a recent science fair, one of the authors (JG) presented a magnetically levitated cart and track. A literature search found no previous testing of magnetically levitated carts. This paper compares a magnetically levitated cart against the two standard low-friction tracks.

  3. Variations in Writing Posture and Cerebral Organization

    ERIC Educational Resources Information Center

    Levy, Jerre; Reid, Marylou

    1976-01-01

    Investigated the relationship between hand writing posture and cerebral dominance of 48 left handed writers and 25 right handed writers. Determined that cerebral dominance is related to handedness and to whether or not the writing hand posture is normal or inverted. (SL)

  4. Restenosis After Balloon Angioplasty for Cerebral Vasospasm

    SciTech Connect

    Sedat, J. Chau, Y.; Popolo, M.; Gindre, S.; Rami, L.; Orban, J. C.

    2009-03-15

    Transluminal balloon dilatation for symptomatic vasospasm after subarachnoid hemorrhage is effective, and clinical studies have shown that it achieves long-lasting dilatation of spastic cerebral arteries. Delayed arterial renarrowing has not been reported. Here we report the case of a 58-year-old woman who presented asymptomatic and permanent restenosis after angioplasty for cerebral vasospasm.

  5. Mobility Experiences of Adolescents with Cerebral Palsy

    ERIC Educational Resources Information Center

    Palisano, Robert J.; Shimmell, Lorie J.; Stewart, Debra; Lawless, John J.; Rosenbaum, Peter L.; Russell, Dianne J.

    2009-01-01

    The purpose of this study was to describe how youth with cerebral palsy experience mobility in their daily lives using a phenomenological approach. The participants were 10 youth with cerebral palsy, 17 to 20 years of age, selected using purposeful sampling with maximum variation strategies. A total of 14 interviews were completed. Transcripts…

  6. Basal ganglia germinoma with progressive cerebral hemiatrophy.

    PubMed

    Liu, E; Robertson, R L; du Plessis, A; Pomeroy, S L

    1999-04-01

    The authors describe a 7-year-old Chinese-American female with a germinoma of the basal ganglia who presented with progressive hemiparesis and cerebral hemiatrophy. The additional finding of markedly elevated antiphospholipid antibodies suggests the possibility of an autoimmune pathogenesis for the progressive cerebral atrophy, as well as the later development of cognitive decline, tics, and obsessive-compulsive behaviors. PMID:10328283

  7. New Hope for Children with Cerebral Palsy.

    ERIC Educational Resources Information Center

    Obringer, S. John

    This paper explains the use of a unique experimental therapy for students with a type of cerebral palsy specifically called Botox. Botulinum Toxin Type A has been tried on a sizable number of students with cerebral palsy in clinical settings to reduce spastic and dystonic movements. By injecting Botox into overly tight heel cords, a normal or near…

  8. UNDERSTANDING CEREBRAL PALSY, A HANDBOOK FOR PARENTS.

    ERIC Educational Resources Information Center

    HATTON, DANIEL A.

    THIS MANUAL, WRITTEN BY A PSYCHOLOGIST, PROVIDES BASIC INFORMATION ABOUT THE NATURE OF CEREBRAL PALSY AND DISCUSSES FEELINGS AND REACTIONS OF PARENTS OF CEREBRAL PALSIED CHILDREN. INFORMATION ABOUT THE BRAIN AND BRAIN DAMAGE IN RELATION TO MOTOR AND EMOTIONAL FUNCTION, PERCEPTION AND INTELLIGENCE IS PRESENTED. PART TWO GIVES INSIGHT INTO PROBLEMS…

  9. Rhinomaxillary mucormycosis with cerebral extension

    PubMed Central

    Goel, Shikha; Palaskar, Sangeeta; Shetty, Vishwa Parkash; Bhushan, Anju

    2009-01-01

    Mucormycosis is a rare opportunistic infection caused by fungus belonging to the order Mucorales. A case of a controlled diabetic male with rhino maxillary mucormycosis, with cerebral extension, is described. The patient presented with hemifacial swelling, a nasal twang in his voice, fever, ocular signs, gross tissue destruction, and was sluggish. Early recognition of mucormycosis is necessary to limit the spread of infection, which can lead to high morbidity and mortality. Therefore, health practitioners should be familiar with the signs and symptoms of the disease. PMID:21886991

  10. Phase dynamics in cerebral autoregulation.

    PubMed

    Latka, Miroslaw; Turalska, Malgorzata; Glaubic-Latka, Marta; Kolodziej, Waldemar; Latka, Dariusz; West, Bruce J

    2005-11-01

    Complex continuous wavelet transforms are used to study the dynamics of instantaneous phase difference delta phi between the fluctuations of arterial blood pressure (ABP) and cerebral blood flow velocity (CBFV) in a middle cerebral artery. For healthy individuals, this phase difference changes slowly over time and has an almost uniform distribution for the very low-frequency (0.02-0.07 Hz) part of the spectrum. We quantify phase dynamics with the help of the synchronization index gamma = (sin delta phi)2 + (cos delta phi)2 that may vary between 0 (uniform distribution of phase differences, so the time series are statistically independent of one another) and 1 (phase locking of ABP and CBFV, so the former drives the latter). For healthy individuals, the group-averaged index gamma has two distinct peaks, one at 0.11 Hz [gamma = 0.59 +/- 0.09] and another at 0.33 Hz (gamma = 0.55 +/- 0.17). In the very low-frequency range (0.02-0.07 Hz), phase difference variability is an inherent property of an intact autoregulation system. Consequently, the average value of the synchronization parameter in this part of the spectrum is equal to 0.13 +/- 0.03. The phase difference variability sheds new light on the nature of cerebral hemodynamics, which so far has been predominantly characterized with the help of the high-pass filter model. In this intrinsically stationary approach, based on the transfer function formalism, the efficient autoregulation is associated with the positive phase shift between oscillations of CBFV and ABP. However, the method is applicable only in the part of the spectrum (0.1-0.3 Hz) where the coherence of these signals is high. We point out that synchrony analysis through the use of wavelet transforms is more general and allows us to study nonstationary aspects of cerebral hemodynamics in the very low-frequency range where the physiological significance of autoregulation is most strongly pronounced. PMID:16024579

  11. The Kinect as an interventional tracking system

    NASA Astrophysics Data System (ADS)

    Wang, Xiang L.; Stolka, Philipp J.; Boctor, Emad; Hager, Gregory; Choti, Michael

    2012-02-01

    This work explores the suitability of low-cost sensors for "serious" medical applications, such as tracking of interventional tools in the OR, for simulation, and for education. Although such tracking - i.e. the acquisition of pose data e.g. for ultrasound probes, tissue manipulation tools, needles, but also tissue, bone etc. - is well established, it relies mostly on external devices such as optical or electromagnetic trackers, both of which mandate the use of special markers or sensors attached to each single entity whose pose is to be recorded, and also require their calibration to the tracked entity, i.e. the determination of the geometric relationship between the marker's and the object's intrinsic coordinate frames. The Microsoft Kinect sensor is a recently introduced device for full-body tracking in the gaming market, but it was quickly hacked - due to its wide range of tightly integrated sensors (RGB camera, IR depth and greyscale camera, microphones, accelerometers, and basic actuation) - and used beyond this area. As its field of view and its accuracy are within reasonable usability limits, we describe a medical needle-tracking system for interventional applications based on the Kinect sensor, standard biopsy needles, and no necessary attachments, thus saving both cost and time. Its twin cameras are used as a stereo pair to detect needle-shaped objects, reconstruct their pose in four degrees of freedom, and provide information about the most likely candidate.

  12. Color Image Processing and Object Tracking System

    NASA Technical Reports Server (NTRS)

    Klimek, Robert B.; Wright, Ted W.; Sielken, Robert S.

    1996-01-01

    This report describes a personal computer based system for automatic and semiautomatic tracking of objects on film or video tape, developed to meet the needs of the Microgravity Combustion and Fluids Science Research Programs at the NASA Lewis Research Center. The system consists of individual hardware components working under computer control to achieve a high degree of automation. The most important hardware components include 16-mm and 35-mm film transports, a high resolution digital camera mounted on a x-y-z micro-positioning stage, an S-VHS tapedeck, an Hi8 tapedeck, video laserdisk, and a framegrabber. All of the image input devices are remotely controlled by a computer. Software was developed to integrate the overall operation of the system including device frame incrementation, grabbing of image frames, image processing of the object's neighborhood, locating the position of the object being tracked, and storing the coordinates in a file. This process is performed repeatedly until the last frame is reached. Several different tracking methods are supported. To illustrate the process, two representative applications of the system are described. These applications represent typical uses of the system and include tracking the propagation of a flame front and tracking the movement of a liquid-gas interface with extremely poor visibility.

  13. Study of the asymptotic dynamic aperture in the NICA collider using symplectic tracking codes

    NASA Astrophysics Data System (ADS)

    Bolshakov, A. E.; Zenkevich, P. R.; Kozlov, O. S.

    2015-12-01

    The dependence of the dynamic aperture in the NICA collider on the number of turns has been calculated by MAD-X tracking code with the two independent algorithms: a program of symplectic tracking PTC (Polymorphic technology Tracking Code) and a program of the thin-lenses tracking method. The results of the numerical integration of particle motion forecast the asymptotic dynamic aperture and the possible losses of particles in the collider.

  14. Track recording plastic compositions

    NASA Technical Reports Server (NTRS)

    Tarle, Gregory (Inventor)

    1983-01-01

    Improved nuclear track recording plastic compositions are provided which exhibit greatly decreased surface roughness when etched to produce visible tracks of energetic nuclear particles which have passed into and/or through said plastic. The improved compositions incorporate a small quantity of a phthalic acid ester into the major plastic component which is derived from the polymerization of monomeric di-ethylene glycol bis allyl carbonate. Di-substituted phthalic acid esters are preferred as the added component, with the further perference that the ester substituent has a chain length of 2 or more carbon atoms. The inclusion of the phthalic acid ester to an extent of from about 1-2% by weight of the plastic compositions is sufficient to drastically reduce the surface roughness ordinarily produced when the track recording plastic is contacted by etchants.

  15. Tracks to therapy

    NASA Technical Reports Server (NTRS)

    Katz, R.; Cucinotta, F. A.

    1999-01-01

    Studies of the structure of particle tracks have led to models of track effects based on radial dose and radiobiological target theory that have been very successful in describing and predicting track effects in physical, chemical, and biological systems. For describing mammalian cellular inactivation two inactivation modes are required, called gamma-kill and ion-kill, the first due to synergistic effects of delta rays from adjacent ion paths thus resembling the effects from gamma rays, and the second to the effects of single ion transits through a cell nucleus. The ion-kill effect is more severe, where the fraction of cells experiencing ion kill is responsible for a decrease in the oxygen enhancement ratio, and an increase in relative biological effectiveness, but these are accompanied by loss of repair, hence to a reduction in the efficiency of fractionation in high LET therapy, as shown by our calculations for radiobiological effects in the "spread out Bragg Peak".

  16. Controlled Document Tracking Software

    Energy Science and Technology Software Center (ESTSC)

    1992-08-24

    MANTRACK is an automated, controlled document tracking system which does the following and reduces staff time required to perform these tasks: generates transmittal letters/receipts for every controlled copy issued (merged from a current distribution list), tracks the return of transmittal receipts, facilitates the check-in of the large number of transmittal receipts returned (using a barcode reader), generates a reminder list which prompts the cyclic review and evaluation of existing documents, generates overdue reminders for themore » return of past-due transmittal receipts, tracks the number of Procedure Change Directives (PCD) currently in effect for each procedure, generates and maintains current distribution lists for each document, generates a current table of contents when updates to the document (usually a procedure manual) are made.« less

  17. Thunderstorm Tracking Using Data from the Brazilian Lightning Detection Network

    NASA Astrophysics Data System (ADS)

    Bourscheidt, V.; Pinto, O.; Naccarato, K.

    2011-12-01

    Severe weather has been noticed as an increasing environmental hazard in the last years. In the same way, pronounced improvements have been made in the forecast and tracking of extreme weather by integrating the meteorological information with lightning data. Thunderstorm tracking software/algorithms using integrated meteorological information and lightning data are nowadays a useful tool to the government and civil defense agencies, with several examples of those systems around the world. Thunderstorm tracking systems that use only lightning data are also available for different regions and give reliable results in general. On the other hand, storm tracking based on lightning data depends on the system characteristics (system performance, number of sensors, detection technology etc.). In the Brazilian case, with a hybrid network with different technologies, a careful analysis is necessary to determine the tracking boundary conditions (distinction of thunderstorm cell, cell life cycle, flash rate, prevailing displacement direction etc). Thus, our goal is to evaluate, based on the already available tracking algorithms, these boundary conditions to find the best approach for a Brazilian lightning-based thunderstorm tracking algorithm/system. This tracking system might help (mainly) on the severe weather forecast/warning, reducing the human/economic damages related to it.

  18. Fast Compressive Tracking.

    PubMed

    Zhang, Kaihua; Zhang, Lei; Yang, Ming-Hsuan

    2014-10-01

    It is a challenging task to develop effective and efficient appearance models for robust object tracking due to factors such as pose variation, illumination change, occlusion, and motion blur. Existing online tracking algorithms often update models with samples from observations in recent frames. Despite much success has been demonstrated, numerous issues remain to be addressed. First, while these adaptive appearance models are data-dependent, there does not exist sufficient amount of data for online algorithms to learn at the outset. Second, online tracking algorithms often encounter the drift problems. As a result of self-taught learning, misaligned samples are likely to be added and degrade the appearance models. In this paper, we propose a simple yet effective and efficient tracking algorithm with an appearance model based on features extracted from a multiscale image feature space with data-independent basis. The proposed appearance model employs non-adaptive random projections that preserve the structure of the image feature space of objects. A very sparse measurement matrix is constructed to efficiently extract the features for the appearance model. We compress sample images of the foreground target and the background using the same sparse measurement matrix. The tracking task is formulated as a binary classification via a naive Bayes classifier with online update in the compressed domain. A coarse-to-fine search strategy is adopted to further reduce the computational complexity in the detection procedure. The proposed compressive tracking algorithm runs in real-time and performs favorably against state-of-the-art methods on challenging sequences in terms of efficiency, accuracy and robustness. PMID:26352631

  19. Relationship of spikes, synaptic activity, and local changes of cerebral blood flow.

    PubMed

    Lauritzen, M

    2001-12-01

    The coupling of electrical activity in the brain to changes in cerebral blood flow (CBF) is of interest because hemodynamic changes are used to track brain function. Recent studies, especially those investigating the cerebellar cortex, have shown that the spike rate in the principal target cell of a brain region (i.e. the efferent cell) does not affect vascular response amplitude. Subthreshold integrative synaptic processes trigger changes in the local microcirculation and local glucose consumption. The spatial specificity of the vascular response on the brain surface is limited because of the functional anatomy of the pial vessels. Within the cortex there is a characteristic laminar flow distribution, the largest changes of which are observed at the depth of maximal synaptic activity (i.e. layer IV) for an afferent input system. Under most conditions, increases in CBF are explained by activity in postsynaptic neurons, but presynaptic elements can contribute. Neurotransmitters do not mediate increases in CBF that are triggered by the concerted action of several second messenger molecules. It is important to distinguish between effective synaptic inhibition and deactivation that increase and decrease CBF and glucose consumption, respectively. In summary, hemodynamic changes evoked by neuronal activity depend on the afferent input function (i.e. all aspects of presynaptic and postsynaptic processing), but are totally independent of the efferent function (i.e., the spike rate of the same region). Thus, it is not possible to conclude whether the output level of activity of a region is increased based on brain maps that use blood-flow changes as markers. PMID:11740198

  20. Hazardous waste tracking issues

    SciTech Connect

    Marvin, R. )

    1993-08-01

    The concept of cradle-to-grave oversight of hazardous waste was established in 1976 under RCRA. Since then, the multicopy Uniform Hazardous Waste Manifest has been a key component in the federal tracking system. The manifests ensure that generators, transporters and TSDFs maintain documentation of hazardous waste shipments. To a large extent, the tracking system has served its intended purpose; nevertheless, certain shortcomings exist. Anyone involved in shipping hazardous waste should be aware of the system's weaknesses and take appropriate measures to compensate for them.

  1. Automatic crack propagation tracking

    NASA Technical Reports Server (NTRS)

    Shephard, M. S.; Weidner, T. J.; Yehia, N. A. B.; Burd, G. S.

    1985-01-01

    A finite element based approach to fully automatic crack propagation tracking is presented. The procedure presented combines fully automatic mesh generation with linear fracture mechanics techniques in a geometrically based finite element code capable of automatically tracking cracks in two-dimensional domains. The automatic mesh generator employs the modified-quadtree technique. Crack propagation increment and direction are predicted using a modified maximum dilatational strain energy density criterion employing the numerical results obtained by meshes of quadratic displacement and singular crack tip finite elements. Example problems are included to demonstrate the procedure.

  2. Computationally efficient Bayesian tracking

    NASA Astrophysics Data System (ADS)

    Aughenbaugh, Jason; La Cour, Brian

    2012-06-01

    In this paper, we describe the progress we have achieved in developing a computationally efficient, grid-based Bayesian fusion tracking system. In our approach, the probability surface is represented by a collection of multidimensional polynomials, each computed adaptively on a grid of cells representing state space. Time evolution is performed using a hybrid particle/grid approach and knowledge of the grid structure, while sensor updates use a measurement-based sampling method with a Delaunay triangulation. We present an application of this system to the problem of tracking a submarine target using a field of active and passive sonar buoys.

  3. Synchronization tracking in pulse position modulation receiver

    NASA Technical Reports Server (NTRS)

    Vilnrotter, Victor A.

    1987-01-01

    A clock pulse generator for decoding pulse position modulation in an optical communication receiver is synchronized by a delay tracking loop which multiplies impulses of a data pulse by the square wave clock pulses from the generator to produce positive impulses when the clock pulse is of one level, and negative impulses when the clock pulse is of another level. A delay tracking loop integrates the impulses and produces an error signal that adjusts the delay so the clock pulses will be synchronized with data pulses. A dead-time tau sub d is provided between data pulses of an interval tau sub p in the data pulse period tau. When synchronized, the average number of positive impulses integrated will equal the average number of negative impulses over the continuous stream of data pulses.

  4. Chronic ketosis and cerebral metabolism.

    PubMed

    DeVivo, D C; Leckie, M P; Ferrendelli, J S; McDougal, D B

    1978-04-01

    The effects of chronic ketosis on cerebral metabolism were determined in adult rats maintained on a high-fat diet for approximately three weeks and compared to a control group of animals. The fat-fed rats had statistically significantly lower blood glucose concentrations and higher blood beta-hydroxybutyrate and acetoacetate concentrations; higher brain concentrations of bound glucose, glucose 6-phosphate, pyruvate, lactate, beta-hydroxybutyrate, citrate, alpha-ketoglutarate, alanine, and adenosine triphosphate (ATP); lower brain concentrations of fructose 1,6-diphosphate, aspartate, adenosine diphosphate (ADP), creatine, cyclic nucleotides, succinyl coenzyme A (CoA), acid-insoluble CoA, and total CoA; and similar brain concentrations of glucose, malate, calculated oxaloacetate, glutamate, glutamine, adenosine monophosphate, phosphocreatine, reduced CoA, acetyl CoA, sodium, potassium, chloride, and water content. The metabolite data in the chronically ketotic rats demonstrate an increase in the cerebral energy reserve and energy charge. These data also suggest negative modification of the enzymes phosphofructokinase, pyruvic dehydrogenase, and alpha-ketoglutaric dehydrogenase; positive modification of glycogen synthase; and possible augmentation of the hexose transport system. There was no demonstrable difference in brain pH, water content, or electrolytes in the two groups of animals. We speculate that the increased brain ATP/ADP ratio is central to most, if not all, the observed metabolic perturbations and may account for the increased neuronal stability that accompanies chronic ketosis. PMID:666275

  5. Cerebral lateralization in simultaneous interpretation.

    PubMed

    Fabbro, F; Gran, L; Basso, G; Bava, A

    1990-07-01

    Cerebral asymmetries for L1 (Italian), L2 (English), and L3 (French, German, Spanish, or Russian) were studied, by using a verbal-manual interference paradigm, in a group of Italian right-handed polyglot female students at the Scuola Superiore di Lingue Moderne per Interpreti e Traduttori (SSLM-School for Interpreters and Translators) of the University of Trieste and in a control group of right-handed monolingual female students at the Medical School of the University of Trieste. In an automatic speech production task no significant cerebral lateralization was found for the mother tongue (L1) either in the interpreting students or in the control group; the interpreting students were not significantly lateralized for the third language (L3), while weak left hemispheric lateralization was shown for L2. A significantly higher degree of verbal-manual interference was found for L1 than for L2 and L3. A significantly higher disruption rate occurred in the meaning-based mode of simultaneous interpretation (from L2 into L1 and vice versa) than in the word-for-word mode (from L2 into L1 and vice versa). No significant overall or hemispheric differences were found during simultaneous interpretation from L1 into L2 or from L2 into L1. PMID:2207622

  6. The transcriptome of cerebral ischemia

    PubMed Central

    VanGilder, Reyna L.; Huber, Jason D.; Rosen, Charles L.; Barr, Taura L.

    2015-01-01

    The molecular causality and response to stroke is complex. Yet, much of the literature examining the molecular response to stroke has focused on targeted pathways that have been well-characterized. Consequently, our understanding of stroke pathophysiology has made little progress by way of clinical therapeutics since tissue plasminogen activator was approved for treatment nearly a decade ago. The lack of clinical translation is in part due to neuron-focused studies, preclinical models of cerebral ischemia and the paradoxical nature of neuro-inflammation. With the evolution of the Stroke Therapy Academic Industry Roundtable criteria streamlining research efforts and broad availability of genomic technologies, the ability to decipher the molecular fingerprint of ischemic stroke is on the horizon. This review highlights preclinical microarray findings of the ischemic brain, discusses the transcriptome of cerebral preconditioning and emphasizes the importance of further characterizing the role of the neurovascular unit and peripheral white blood cells in mediating stroke damage and repair within the penumbra. PMID:22381515

  7. Cerebral Syndromes of Diabetes Mellitus

    PubMed Central

    Shavelle, Henry S.

    1969-01-01

    Three labile diabetic patients had recurring episodes of altered sensorium. Each had severe cerebrovascular disease with superimposed metabolic derangements, including ketoacidosis, hyperglycemia without ketosis, mild uremia, and possibly cerebral edema. Two of the patients were examined postmortem. Severe leptomeningeal scarring, basal ganglial calcification and destruction of small intracerebral vessels without evidence of large vessel atherosclerosis were found unexpectedly in one patient, a rare occurrence in this country although recently reported from Europe. The other patient had large vessel atherosclerosis only. The clinical expression of the vascular disease was modified by concurrent abnormalities and reflected the sum total of the complexities which coexisted. The pathophysiology of the unconscious state necessarily depends on the inciting factors. Ketoacidotic coma is associated with depressed cerebral oxygen consumption. Spinal fluid pH is usually maintained during ketosis but is sometimes lowered inadvertently during bicarbonate therapy, with resultant coma. Other variables influencing the clinical expression, with or without ketosis, would include, among others, blood viscosity alterations, rapid decrements in blood sugar, and existing degrees of lactic acidosis. The increasing life-span of the juvenile diabetics, favorably influenced by improved management and recently by hemodialysis, may uncover vascular complications heretofore rarely seen and create additional diagnostic and therapeutic enigmas. ImagesFigure 1.Figure 2.Figure 3. PMID:5798497

  8. [Cerebral vasospasm after subarachnoid hemorrhage].

    PubMed

    Milojević, T M; Baljozović, B V; Rakić, M Lj; Nestorović, B D; Dostanić, M M; Milaković, B D; Kojić, Z Z; Repac, N R; Cvrkota, I S

    2008-01-01

    Cerebral vasospasm causes permanent neurolological deficit or death occurance in 13% of clinical cases. Peak frequency is from 8-10th day after SAH. The purpose of this study is factor analysis that may have influence on vasospasm development , as well as predictor determination. The study is prospective and analysis 192 patients treated in Institute of Neurosurgery, Clinical Centre of Serbia, Belgrade. The majority of patients were admitted in hospital in first four days after SAH, and 184 had GCS over 7. Univariate methods of factor analysis were used, and for significance of predictors influence testing multivariante regression analysis was used. Vasospasm occurred in 22,40% of all cases. No relationships have been found between sex, age, previous hypertension, timing of surgery, appearance of hydrocephalus and intracerebral hematoma, hypertermia or mean arterial blood pressure, with occurrence of cerebral vasospasm. Factors with significantly associated with the occurance of vasospasm were: hearth disease, hypernatriemia, Hct, clinical grade on admission as well as preoperative clinical grade and Fisher CT scan grade. In the first four days after SAH, Fisher scan grade, preoperative clinical grade and Hct, appeared as predictors. After four days, clinical grade on admission and hypernatiemia, showed as poredictors. PMID:18792575

  9. Septic cerebral venous sinus thrombosis.

    PubMed

    Khatri, Ismail A; Wasay, Mohammad

    2016-03-15

    Septic cerebral venous sinus thrombosis, once a common and deadly disease, has fortunately become rare now. Not only that the incidence has fallen significantly after the antibiotic era, the morbidity and mortality has also decreased substantially. Cavernous sinus thrombosis is by far the commonest form of septic cerebral venous sinus thrombosis. Due to its rare occurrence, a lot of current generation clinicians have not encountered the entity in person. Despite all the advances in diagnostic modalities, a high index of clinical suspicion remains the mainstay in prompt diagnosis and management of this potentially lethal condition. Keeping this in view, the authors have reviewed the subject including the old literature and have summarized the current approach to diagnosis and management. Septic cavernous thrombosis is a fulminant disease with dramatic presentation in most cases comprised of fever, periorbital pain and swelling, associated with systemic symptoms and signs. The preceding infection is usually in the central face or paranasal sinuses. The disease rapidly spreads to contralateral side and if remains undiagnosed and untreated can result in severe complications or even death. Prompt diagnosis using radiological imaging in suspected patient, early use of broad spectrum antibiotics, and judicial use of anticoagulation may save the life and prevent disability. Surgery is used only to treat the nidus of infection. PMID:26944152

  10. Lifetime costs of cerebral palsy.

    PubMed

    Kruse, Marie; Michelsen, Susan Ishøy; Flachs, Esben Meulengracht; Brønnum-Hansen, Henrik; Madsen, Mette; Uldall, Peter

    2009-08-01

    This study quantified the lifetime costs of cerebral palsy (CP) in a register-based setting. It was the first study outside the US to assess the lifetime costs of CP. The lifetime costs attributable to CP were divided into three categories: health care costs, productivity costs, and social costs. The population analysed was retrieved from the Danish Cerebral Palsy Register, which covers the eastern part of the country and has registered about half of the Danish population of individuals with CP since 1950. For this study we analysed 2367 individuals with CP, who were born in 1930 to 2000 and were alive in 2000. The prevalence of CP in eastern Denmark was approximately 1.7 per 1000. Information on productivity and the use of health care was retrieved from registers. The lifetime cost of CP was about 860,000 euro for men and about 800,000 euro for women. The largest component was social care costs, particularly during childhood. A sensitivity analysis found that alterations in social care costs had a small effect, whereas lowering the discount rate from 5 to 3 per cent markedly increased total lifetime costs. Discounting decreases the value of costs in the future compared with the present. The high social care costs and productivity costs associated with CP point to a potential gain from labour market interventions that benefit individuals with CP. PMID:19416329

  11. A New Inertial Aid Method for High Dynamic Compass Signal Tracking Based on a Nonlinear Tracking Differentiator

    PubMed Central

    Guo, Yao; Wu, Wenqi; Tang, Kanghua

    2012-01-01

    In Compass/INS integrated navigation systems, feedback inertial navigation solutions to baseband tracking loops may eliminate receiver dynamic effects, and effectively improve the tracking accuracy and sensitivity. In the conventional inertially-aided tracking loop, the satellite-receiver line-of-sight velocity is used directly to adjust local carrier frequency. However, if the inertial solution drifts, the phase tracking error will be enlarged. By using Kalman filter based carrier phase tracking loop, this paper introduces a new inertial aid method, in which the line-of-sight jerk obtained from inertial acceleration by a nonlinear tracking differentiator is used to adjust relevant parameters of the Kalman filter's process noise matrix. Validation is achieved through high dynamic Compass B3 signal with line-of-sight jerk of 10 g/s collected by a GNSS simulator. Experimental results indicate that the new inertial aid method proposed in this paper is free of the impact of the receiver dynamic and inertial errors. Therefore, when the integrated navigation system is starting or re-tracking after losing lock, the inertial error is absent from the navigation solution correction that induces large drift, and the new aid method proposed in this paper can track highly dynamic signals. PMID:22969365

  12. Integrated mobile robot control

    NASA Technical Reports Server (NTRS)

    Amidi, Omead; Thorpe, Charles

    1991-01-01

    This paper describes the structure, implementation, and operation of a real-time mobile robot controller which integrates capabilities such as: position estimation, path specification and tracking, human interfaces, fast communication, and multiple client support. The benefits of such high-level capabilities in a low-level controller was shown by its implementation for the Navlab autonomous vehicle. In addition, performance results from positioning and tracking systems are reported and analyzed.

  13. Intelligent wireless asset tracking of packaged gases

    NASA Astrophysics Data System (ADS)

    Mason, A.; Al-Shamma'a, A. I.; Shaw, A.; Irven, J.; Wiktorowicz, R.

    2007-07-01

    Gas cylinders are used in many different situations, such as in research, in industry, in healthcare, and even in the home. Due to demand in such a wide variety of circumstances, there is the inevitable ambition of gas suppliers to improve the efficiency of their business. To this end, a tracking system is proposed in this paper in order to provide such improved efficiency whilst also integrating sensors in order to monitor gas cylinders from a safety perspective.

  14. Dust Devil Tracks

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 8 May 2002) The Science This image, centered near 50.0 S and 17.7 W displays dust devil tracks on the surface. Most of the lighter portions of the image likely have a thin veneer of dust settled on the surface. As a dust devil passes over the surface, it acts as a vacuum and picks up the dust, leaving the darker substrate exposed. In this image there is a general trend of many of the tracks running from east to west or west to east, indicating the general wind direction. There is often no general trend present in dust devil tracks seen in other images. The track patterns are quite ephemeral and can completely change or even disappear over the course of a few months. Dust devils are one of the mechanisms that Mars uses to constantly pump dust into the ubiquitously dusty atmosphere. This atmospheric dust is one of the main driving forces of the present Martian climate. The Story Vrrrrooooooooom. Think of a tornado, the cartoon Tasmanian devil, or any number of vacuum commercials that powerfully suck up swirls of dust and dirt. That's pretty much what it's like on the surface of Mars a lot of the time. Whirlpools of wind called

  15. Tracking Speech Sound Acquisition

    ERIC Educational Resources Information Center

    Powell, Thomas W.

    2011-01-01

    This article describes a procedure to aid in the clinical appraisal of child speech. The approach, based on the work by Dinnsen, Chin, Elbert, and Powell (1990; Some constraints on functionally disordered phonologies: Phonetic inventories and phonotactics. "Journal of Speech and Hearing Research", 33, 28-37), uses a railway idiom to track gains in…

  16. Energy rays tracking device

    SciTech Connect

    Monk, R.J.

    1981-05-12

    An energy rays tracking device includes a receiver for fixing a position relative to the direction of maximum energy rays, a prime mover for maintaining the alignment of the receiver and an energy rays user, an energy rays tracker for controlling the power to the prime mover in response to the receiver, a timed tracker for controlling the prime mover when the energy rays tracker is not functioning due to energy rays being too diffused, an energy sensitive element for detecting the presence or absence of energy rays, and a power controller responsive to the energy sensitive element for repositioning the receiver and the energy rays user for the following period of tracking is disclosed. The receiver includes an enclosure which only allows a selected pattern of direct rays to penetrate into the enclosure. A razor sharp edge at the opening of the enclosure maintains the outermost direct energy rays undiffused. A differential sensor sensitive to direct energy rays is installed inside the enclosure for determining the direction of the direct energy rays. In an application for tracking the sun, the time tracker uses a piecewise linear method of tracking. In the return cycle during the night, the return is interspersed with a wash cycle for cleaning the energy rays user.

  17. Personal Tracking Charts

    MedlinePlus

    ... only on Monday, Wednesday, and Friday. Keep an eye out for allergic reactions. I should take Prezista with food. year keeping track of my periods month mark the Type of Flow in the boxes below L =exceptionally light N =normal h =exceptionally heavy S =spotting O =none ...

  18. Manure Tracking Book

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This document provides an example of the ‘Manure Tracking Book’ that was used by the fifty-four Wisconsin dairy farmers who participated in the “On Farmers’ Ground” nutrient management research project. This Book was used to systematically tract how, when and where farmers spread manure, and factors...

  19. General defocusing particle tracking.

    PubMed

    Barnkob, Rune; Kähler, Christian J; Rossi, Massimiliano

    2015-09-01

    A General Defocusing Particle Tracking (GDPT) method is proposed for tracking the three-dimensional motion of particles in Lab-on-a-chip systems based on a set of calibration images and the normalized cross-correlation function. In comparison with other single-camera defocusing particle-tracking techniques, GDPT possesses a series of key advantages: it is applicable to particle images of arbitrary shapes, it is intuitive and easy to use, it can be used without advanced knowledge of optics and velocimetry theory, it is robust against outliers and overlapping particle images, and it requires only equipment which is standard in microfluidic laboratories. We demonstrate the method by tracking the three-dimensional motion of 2 μm spherical particles in a microfluidic channel using three different optical arrangements. The position of the particles was measured with an estimated uncertainty of 0.1 μm in the in-plane direction and 2 μm in the depth direction for a measurement volume of 1510 × 1270 × 160 μm(3). A ready-to-use GUI implementation of the method can be acquired on . PMID:26201498

  20. Spiral track oven

    SciTech Connect

    Drobilisch, Sandor

    1998-12-20

    Final report on development of a continuously operating oven system in which the parts are progressing automatically on a spiral track for in-line service installation for the production of electronic and/or other components to be heat cured or dried.

  1. Tracking the Invisible Faculty

    ERIC Educational Resources Information Center

    Gravois, John

    2006-01-01

    For decades it has been happening everywhere in academe, but nowhere in particular. The sweeping shift toward non-tenure-track academic labor has been one of the most worried-over trends in American higher education. But it has been charted mostly with broad-brush data, which give little indication of the trend's progress at the institutional…

  2. Dust Devil Tracks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Context image for PIA03052 Dust Devil Tracks

    These dust devil tracks are located in the region surrounding Hooke Crater.

    Image information: VIS instrument. Latitude 46.6S, Longitude 316.1E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  3. Asset tracking systems.

    PubMed

    2006-11-01

    Asset tracking systems are used in healthcare to find objects--medical devices and other hospital equipment--and to record the physical location of those objects over time. Interest in asset tracking is growing daily, but the technology is still evolving, and so far very few systems have been implemented in hospitals. This situation is likely to change over the next few years, at which point many hospitals will be faced with choosing a system. We evaluated four asset tracking systems from four suppliers: Agility Healthcare Solutions, Ekahau, Radianse, and Versus Technology. We judged the systems' performance for two "levels" of asset tracking. The first level is basic locating--simply determining where in the facility an item can be found. This may be done because the equipment needs routine inspection and preventive maintenance or because it is required for recall purposes; or the equipment may be needed, often urgently, for clinical use. The second level, which is much more involved, is inventory optimization and workflow improvement. This entails analyzing asset utilization based on historical location data to improve the use, distribution, and processing of equipment. None of the evaluated products is ideal for all uses--each has strengths and weaknesses. In many cases, hospitals will have to select a product based on their specific needs. For example, they may need to choose between a supplier whose system is easy to install and a supplier whose tags have a long battery operating life. PMID:17278873

  4. TRACKING Trounces Test Scores

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2004

    2004-01-01

    This article presents an adaptation of an article from School Board News, January 6, 2004 edition. The article describes the effort of de-tracking students of varying ability levels, made by officials of South Side High School, in Rockville Centre, New York, and Noble High School, in North Berwick, Maine. Officials from both schools say that the…

  5. Energy Tracking Diagrams

    ERIC Educational Resources Information Center

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-01-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the "Next Generation Science Standards," the primary conceptual learning goal is for learners to conserve energy as they "track" the transfers and transformations of energy within, into, or out of the system of…

  6. Tracking Politics with POWER

    ERIC Educational Resources Information Center

    Moreira, Silvio; Batista, David S.; Carvalho, Paula; Couto, Francisco M.; Silva, Mario J.

    2013-01-01

    Purpose: POWER is an ontology of political processes and entities. It is designed for tracking politicians, political organizations and elections, both in mainstream and social media. The aim of this paper is to propose a data model to describe political agents and their relations over time. Design/methodology/approach: The authors propose a data…

  7. Caring for Children with Cerebral Palsy: A Team Approach.

    ERIC Educational Resources Information Center

    Dormans, John P., Ed.; Pellegrino, Louis, Ed.

    Twenty-one papers on caring for children with cerebral palsy are organized into four sections, including: (1) cerebral palsy and the interdisciplinary team approach; (2) management of impairments related to cerebral palsy; (3) preventing disability by optimizing function of the child with cerebral palsy; and (4) preventing handicap by creating…

  8. Cerebral tissue oxygenation impairment during experimental cerebral malaria

    PubMed Central

    Cabrales, Pedro; Martins, Yuri C; Ong, Peng Kai; Zanini, Graziela M; Frangos, John A; Carvalho, Leonardo JM

    2013-01-01

    Ischemia and hypoxia have been implicated in cerebral malaria (CM) pathogenesis, although direct measurements of hypoxia have not been conducted. C57BL/6 mice infected with Plasmodium berghei ANKA (PbA) develop a neurological syndrome known as experimental cerebral malaria (ECM), whereas BALB/c mice are resistant to ECM. In this study, intravital microscopy methods were used to quantify hemodynamic changes, vascular/tissue oxygen (O2) tension (PO2), and perivascular pH in vivo in ECM and non-ECM models, employing a closed cranial window model. ECM mice on day 6 of infection showed marked decreases in pial blood flow, vascular (arteriolar, venular), and perivascular PO2, perivascular pH, and systemic hemoglobin levels. Changes were more dramatic in mice with late-stage ECM compared with mice with early-stage ECM. These changes led to drastic decreases in O2 delivery to the brain tissue. In addition, ECM animals required a greater PO2 gradient to extract the same amount of O2 compared with non-infected animals, as the pial tissues extract O2 from the steepest portion of the blood O2 equilibrium curve. ECM animals also showed increased leukocyte adherence in postcapillary venules, and the intensity of adhesion was inversely correlated with blood flow and O2 extraction. PbA-infected BALB/c mice displayed no neurological signs on day 6 and while they did show changes similar to those observed in C57BL/6 mice (decreased pial blood flow, vascular/tissue PO2, perivascular pH, hemoglobin levels), non-ECM animals preserved superior perfusion and oxygenation compared with ECM animals at similar anemia and parasitemia levels, resulting in better O2 delivery and O2 extraction by the brain tissue. In conclusion, direct quantitative assessment of pial hemodynamics and oxygenation in vivo revealed that ECM is associated with severe progressive brain tissue hypoxia and acidosis. PMID:24128424

  9. Is Vasomotion in Cerebral Arteries Impaired in Alzheimer’s Disease?

    PubMed Central

    Di Marco, Luigi Yuri; Farkas, Eszter; Martin, Chris; Venneri, Annalena; Frangi, Alejandro F.

    2015-01-01

    Abstract A substantial body of evidence supports the hypothesis of a vascular component in the pathogenesis of Alzheimer’s disease (AD). Cerebral hypoperfusion and blood-brain barrier dysfunction have been indicated as key elements of this pathway. Cerebral amyloid angiopathy (CAA) is a cerebrovascular disorder, frequent in AD, characterized by the accumulation of amyloid-β (Aβ) peptide in cerebral blood vessel walls. CAA is associated with loss of vascular integrity, resulting in impaired regulation of cerebral circulation, and increased susceptibility to cerebral ischemia, microhemorrhages, and white matter damage. Vasomotion— the spontaneous rhythmic modulation of arterial diameter, typically observed in arteries/arterioles in various vascular beds including the brain— is thought to participate in tissue perfusion and oxygen delivery regulation. Vasomotion is impaired in adverse conditions such as hypoperfusion and hypoxia. The perivascular and glymphatic pathways of Aβ clearance are thought to be driven by the systolic pulse. Vasomotion produces diameter changes of comparable amplitude, however at lower rates, and could contribute to these mechanisms of Aβ clearance. In spite of potential clinical interest, studies addressing cerebral vasomotion in the context of AD/CAA are limited. This study reviews the current literature on vasomotion, and hypothesizes potential paths implicating impaired cerebral vasomotion in AD/CAA. Aβ and oxidative stress cause vascular tone dysregulation through direct effects on vascular cells, and indirect effects mediated by impaired neurovascular coupling. Vascular tone dysregulation is further aggravated by cholinergic deficit and results in depressed cerebrovascular reactivity and (possibly) impaired vasomotion, aggravating regional hypoperfusion and promoting further Aβ and oxidative stress accumulation. PMID:25720414

  10. Neonatal risk factors for cerebral palsy in very preterm babies: case-control study.

    PubMed Central

    Murphy, D. J.; Hope, P. L.; Johnson, A.

    1997-01-01

    OBJECTIVE: To identify neonatal risk factors for cerebral palsy among very preterm babies and in particular the associations independent of the coexistence of antenatal and intrapartum factors. DESIGN: Case-control study. SETTING: Oxford health region. SUBJECTS: Singleton babies born between 1984 and 1990 at less than 32 weeks' gestation who survived to discharge from hospital: 59 with cerebral palsy and 234 randomly selected controls without cerebral palsy. MAIN OUTCOME MEASURES: Adverse neonatal factors expressed as odds ratios and 95% confidence intervals. RESULTS: Factors associated with an increased risk of cerebral palsy after adjustment for gestational age and the presence of previously identified antenatal and intrapartum risk factors were patent ductus arteriosus (odds ratio 2.3; 95% confidence interval 1.2 to 4.5), hypotension (2.3; 1.3 to 4.7), blood transfusion (4.8; 2.5 to 9.3), prolonged ventilation (4.8; 2.5 to 9.0), pneumothorax (3.5; 1.6 to 7.6), sepsis (3.6; 1.8 to 7.4), hyponatraemia (7.9; 2.1 to 29.6) and total parenteral nutrition (5.5; 2.8 to 10.5). Seizures were associated with an increased risk of cerebral palsy (10.0; 4.1 to 24.7), as were parenchymal damage (32; 12.4 to 84.4) and appreciable ventricular dilatation (5.4; 3.0 to 9.8) detected by cerebral ultrasound. CONCLUSION: A reduction in the rate of cerebral palsy in very preterm babies requires an integrated approach to management throughout the antenatal, intrapartum, and neonatal periods. PMID:9040385

  11. The effect of ventricular assist devices on cerebral blood flow and blood pressure fractality.

    PubMed

    Bellapart, Judith; Chan, Gregory S H; Tzeng, Yu-Chieh; Ainslie, Philip N; Dunster, Kimble R; Barnett, Adrian G; Boots, Rob; Fraser, John F

    2011-09-01

    Biological signals often exhibit self-similar or fractal scaling characteristics which may reflect intrinsic adaptability to their underlying physiological system. This study analysed fractal dynamics of cerebral blood flow in patients supported with ventricular assist devices (VAD) to ascertain if sustained modifications of blood pressure waveform affect cerebral blood flow fractality. Simultaneous recordings of arterial blood pressure and cerebral blood flow velocity using transcranial Doppler were obtained from five cardiogenic shock patients supported by VAD, five matched control patients and five healthy subjects. Computation of a fractal scaling exponent (α) at the low-frequency time scale by detrended fluctuation analysis showed that cerebral blood flow velocity exhibited 1/f fractal scaling in both patient groups (α = 0.95 ± 0.09 and 0.97 ± 0.12, respectively) as well as in the healthy subjects (α = 0.86 ± 0.07). In contrast, fluctuation in blood pressure was similar to non-fractal white noise in both patient groups (α = 0.53 ± 0.11 and 0.52 ± 0.09, respectively) but exhibited 1/f scaling in the healthy subjects (α = 0.87 ± 0.04, P < 0.05 compared with the patient groups). The preservation of fractality in cerebral blood flow of VAD patients suggests that normal cardiac pulsation and central perfusion pressure changes are not the integral sources of cerebral blood flow fractality and that intrinsic vascular properties such as cerebral autoregulation may be involved. However, there is a clear difference in the fractal scaling properties of arterial blood pressure between the cardiogenic shock patients and the healthy subjects. PMID:21775798

  12. Cerebral Hypoperfusion Precedes Nausea During Centrifugation

    NASA Technical Reports Server (NTRS)

    Serrador, Jorge M.; Schlegel, Todd T.; Black, F. Owen; Wood, Scott J.

    2004-01-01

    Nausea and motion sickness are important operational concerns for aviators and astronauts. Understanding underlying mechanisms associated with motion sickness may lead to new treatments. The goal of this work was to determine if cerebral blood flow changes precede the development of nausea in motion sick susceptible subjects. Cerebral flow velocity in the middle cerebral artery (transcranial Doppler), blood pressure (Finapres) and end-tidal CO2 were measured while subjects were rotated on a centrifuge (250 degrees/sec). Following 5 min of rotation, subjects were translated 0.504 m off-center, creating a +lGx centripetal acceleration in the nasal-occipital plane. Ten subjects completed the protocol without symptoms while 5 developed nausea (4 while 6ff-center and 1 while rotating on-center). Prior to nausea, subjects had significant increases in blood pressure (+13plus or minus 3 mmHg, P less than 0.05) and cerebrovascular resistance (+46 plus or minus 17%, P less than 0.05) and decreases in cerebral flow velocity both in the second (-13 plus or minus 4%) and last minute (-22 plus or minus 5%) before symptoms (P less than 0.05). In comparison, controls demonstrated no change in blood pressure or cerebrovascular resistance in the last minute of off-center rotation and only a 7 plus or minus 2% decrease in cerebral flow velocity. All subjects had significant hypocapnia (-3.8 plus or minus 0.4 mmHg, P less than 0.05), however this hypocapnia could not fully explain the cerebral hypoperfusion associated with the development of nausea. These data indicate that reductions in cerebral blood flow precede the development of nausea. Further work is necessary to determine what role cerebral hypoperfusion plays in motion sickness and whether cerebral hypoperfusion can be used to predict the development of nausea in susceptible individuals.

  13. Cerebral Lactate Metabolism After Traumatic Brain Injury.

    PubMed

    Patet, Camille; Suys, Tamarah; Carteron, Laurent; Oddo, Mauro

    2016-04-01

    Cerebral energy dysfunction has emerged as an important determinant of prognosis following traumatic brain injury (TBI). A number of studies using cerebral microdialysis, positron emission tomography, and jugular bulb oximetry to explore cerebral metabolism in patients with TBI have demonstrated a critical decrease in the availability of the main energy substrate of brain cells (i.e., glucose). Energy dysfunction induces adaptations of cerebral metabolism that include the utilization of alternative energy resources that the brain constitutively has, such as lactate. Two decades of experimental and human investigations have convincingly shown that lactate stands as a major actor of cerebral metabolism. Glutamate-induced activation of glycolysis stimulates lactate production from glucose in astrocytes, with subsequent lactate transfer to neurons (astrocyte-neuron lactate shuttle). Lactate is not only used as an extra energy substrate but also acts as a signaling molecule and regulator of systemic and brain glucose use in the cerebral circulation. In animal models of brain injury (e.g., TBI, stroke), supplementation with exogenous lactate exerts significant neuroprotection. Here, we summarize the main clinical studies showing the pivotal role of lactate and cerebral lactate metabolism after TBI. We also review pilot interventional studies that examined exogenous lactate supplementation in patients with TBI and found hypertonic lactate infusions had several beneficial properties on the injured brain, including decrease of brain edema, improvement of neuroenergetics via a "cerebral glucose-sparing effect," and increase of cerebral blood flow. Hypertonic lactate represents a promising area of therapeutic investigation; however, larger studies are needed to further examine mechanisms of action and impact on outcome. PMID:26898683

  14. Nanoscale Phase Transitions under Extreme Conditions within an Ion Track

    SciTech Connect

    Zhang, Jiaming; Lang, Maik; Ewing, Rodney C.; Devanathan, Ramaswami; Weber, William J.; Toulemonde, Marcel

    2010-06-30

    The dynamics of track development due to the passage of relativistic heavy ions through solids is a long-standing issue relevant to nuclear materials, age-dating of minerals, space exploration, and nanoscale fabrication of novel devices. We have integrated experimental and simulation approaches to investigate nanoscale phase transitions under the extreme conditions created within single tracks of relativistic ions in Gd2O3(TiO2)x and Gd2Zr2-xTixO7. Track size and internal structure depend on energy-density deposition, irradiation temperature, and material composition. Molecular dynamics methods based on the thermal spike model have simulated, for the first time, the internal structure of individual tracks, consistent with experimental observations. Individual ion tracks have nanoscale core-shell structures that provide a unique record of the phase transition pathways under extreme conditions.

  15. SOFIA tracking subsystem: results of assembly, operation, and calibration tests

    NASA Astrophysics Data System (ADS)

    Bittner, Hermann; Erdmann, Matthias; Schmolke, Juergen; Lattner, Klaus; Levin, Torsten; Erhard, Markus

    2003-02-01

    The SOFIA airborne telescope has a Tracking Subsystem for stellar acquisition, tracking, and pointing. The system has three high-performance imagers: the boresighted wide field (6 degrees FOV) and fine field imagers (70 arcminutes FOV), and the main-telescope-optics sharing focal plane imager (8 arcminutes FOV). The imagers are controlled by 3 CCD head controllers, an overall imager controller, and a tracker controller providing the tracking error signals from the objects observed by the imagers. There have been several test steps in the assembly, integration, and verification of the Tracking Subsystem. The paper presents the fully integrated system as actually built, the results of the thermal-vacuum and vibration tests of the fine field imager, the tested operational/functional S/W performance, as well as the results of the geometric and radiometric calibrations of the imagers.

  16. Computational Image Analysis Reveals Intrinsic Multigenerational Differences between Anterior and Posterior Cerebral Cortex Neural Progenitor Cells.

    PubMed

    Winter, Mark R; Liu, Mo; Monteleone, David; Melunis, Justin; Hershberg, Uri; Goderie, Susan K; Temple, Sally; Cohen, Andrew R

    2015-10-13

    Time-lapse microscopy can capture patterns of development through multiple divisions for an entire clone of proliferating cells. Images are taken every few minutes over many days, generating data too vast to process completely by hand. Computational analysis of this data can benefit from occasional human guidance. Here we combine improved automated algorithms with minimized human validation to produce fully corrected segmentation, tracking, and lineaging results with dramatic reduction in effort. A web-based viewer provides access to data and results. The improved approach allows efficient analysis of large numbers of clones. Using this method, we studied populations of progenitor cells derived from the anterior and posterior embryonic mouse cerebral cortex, each growing in a standardized culture environment. Progenitors from the anterior cortex were smaller, less motile, and produced smaller clones compared to those from the posterior cortex, demonstrating cell-intrinsic differences that may contribute to the areal organization of the cerebral cortex. PMID:26344906

  17. Computational Image Analysis Reveals Intrinsic Multigenerational Differences between Anterior and Posterior Cerebral Cortex Neural Progenitor Cells

    PubMed Central

    Winter, Mark R.; Liu, Mo; Monteleone, David; Melunis, Justin; Hershberg, Uri; Goderie, Susan K.; Temple, Sally; Cohen, Andrew R.

    2015-01-01

    Summary Time-lapse microscopy can capture patterns of development through multiple divisions for an entire clone of proliferating cells. Images are taken every few minutes over many days, generating data too vast to process completely by hand. Computational analysis of this data can benefit from occasional human guidance. Here we combine improved automated algorithms with minimized human validation to produce fully corrected segmentation, tracking, and lineaging results with dramatic reduction in effort. A web-based viewer provides access to data and results. The improved approach allows efficient analysis of large numbers of clones. Using this method, we studied populations of progenitor cells derived from the anterior and posterior embryonic mouse cerebral cortex, each growing in a standardized culture environment. Progenitors from the anterior cortex were smaller, less motile, and produced smaller clones compared to those from the posterior cortex, demonstrating cell-intrinsic differences that may contribute to the areal organization of the cerebral cortex. PMID:26344906

  18. Cerebral blood flow in the newborn infant.

    PubMed Central

    Pryds, O.; Edwards, A. D.

    1996-01-01

    Studies of CBF have provided some insight into cerebrovascular physiology and pharmacology. However, the precise relation between CBF and cerebral damage remains elusive, and there is no definition of a threshold CBF below which ischaemic brain damage always occurs. Measurement of CBF thus does not currently provide a secure guide in the clinical management of sick infants. Further work, particularly using techniques like magnetic resonance imaging and NIRS, which provide data in addition to CBF measurements, may yet disclose strategies which manipulate CBF to reduce cerebral ischaemia. While cerebral injury remains a substantial problem in neonatal intensive care, such research is urgently needed. Images Figure 3 PMID:8653440

  19. The evolution of cerebral revascularization surgery.

    PubMed

    Hayden, Melanie G; Lee, Marco; Guzman, Raphael; Steinberg, Gary K

    2009-05-01

    Among the relatively few surgeons to be awarded the Nobel Prize was Alexis Carrel, a French surgeon and pioneer in revascularization surgery at the turn of the 20th century. The authors trace the humble beginnings of cerebral revascularization surgery through to the major developments that helped shape the modern practice of cerebral bypass surgery. They discuss the cornerstone studies in the development of this technique, including the Extracranial/Intracranial Bypass Study initiated in 1977. Recent innovations, including modern techniques to monitor cerebral blood flow, microanastomosis techniques, and ongoing trials that play an important role in the evolution of this field are also evaluated. PMID:19408995

  20. Remote sensing of water tracks

    NASA Astrophysics Data System (ADS)

    Trochim, E. D.; Prakash, A.; Kane, D. L.; Romanovsky, V. E.

    2016-03-01

    Water tracks are an intrinsic part of the surficial drainage network in the foothills of the Brooks Range, Alaska. They preferentially transport water off hillslopes and represent the interplay between hydrology, vegetation, geomorphology, and permafrost characteristics. This research on mapping the location of water tracks builds on previous work which demonstrated that different types of water tracks exist due to difference primarily driven by geomorphology. We used a combination method where spectral classifications, texture, and topography were fed into random forests to identify the water track classes. The most accurate distributions were obtained for the organic-rich and wide water track classes. The distinct linear shapes of the water tracks could also be visualized for many of the classes, especially in areas where the water tracks were particularly discrete. The biggest challenges to mapping the water tracks were due to class imbalances and high variability within and overlapping between classes. This research presents a significant step forward in understanding periglacial landscape dynamics.

  1. Myogenic and metabolic feedback in cerebral autoregulation: Putative involvement of arachidonic acid-dependent pathways.

    PubMed

    Berg, Ronan M G

    2016-07-01

    The present paper presents a mechanistic model of cerebral autoregulation, in which the dual effects of the arachidonic acid metabolites 20-hydroxyeicosatetraenoic acid (20-HETE) and epoxyeicosatrienoic acids (EETs) on vascular smooth muscle mediate the cerebrovascular adjustments to a change in cerebral perfusion pressure (CPP). 20-HETE signalling in vascular smooth muscle mediates myogenic feedback to changes in vessel wall stretch, which may be modulated by metabolic feedback through EETs released from astrocytes and endothelial cells in response to changes in brain tissue oxygen tension. The metabolic feedback pathway is much faster than 20-HETE-dependent myogenic feedback, and the former thus initiates the cerebral autoregulatory response, while myogenic feedback comprises a relatively slower mechanism that functions to set the basal cerebrovascular tone. Therefore, assessments of dynamic cerebral autoregulation, which may provide information on the response time of the cerebrovasculature, may specifically be used to yield information on metabolic feedback mechanisms, while data based on assessments of static cerebral autoregulation represent the integrated functionality of myogenic and metabolic feedback. PMID:27241246

  2. Systematic investigation of transcription factors critical in the protection against cerebral ischemia by Danhong injection.

    PubMed

    Wei, Junying; Zhang, Yanqiong; Jia, Qiang; Liu, Mingwei; Li, Defeng; Zhang, Yi; Song, Lei; Hu, Yanzhen; Xian, Minghua; Yang, Hongjun; Ding, Chen; Huang, Luqi

    2016-01-01

    Systematic investigations of complex pathological cascades during ischemic brain injury help to elucidate novel therapeutic targets against cerebral ischemia. Although some transcription factors (TFs) involved in cerebral ischemia, systematic surveys of their changes during ischemic brain injury have not been reported. Moreover, some multi-target agents effectively protected against ischemic stroke, but their mechanisms, especially the targets of TFs, are still unclear. Therefore, a comprehensive approach by integrating network pharmacology strategy and a new concatenated tandem array of consensus transcription factor response elements method to systematically investigate the target TFs critical in the protection against cerebral ischemia by a medication was first reported, and then applied to a multi-target drug, Danhong injection (DHI). High-throughput nature and depth of coverage, as well as high quantitative accuracy of the developed approach, make it more suitable for analyzing such multi-target agents. Results indicated that pre-B-cell leukemia transcription factor 1 and cyclic AMP-dependent transcription factor 1, along with six other TFs, are putative target TFs for DHI-mediated protection against cerebral ischemia. This study provides, for the first time, a systematic investigation of the target TFs critical to DHI-mediated protection against cerebral ischemia, as well as reveals more potential therapeutic targets for ischemic stroke. PMID:27431009

  3. Systematic investigation of transcription factors critical in the protection against cerebral ischemia by Danhong injection

    PubMed Central

    Wei, Junying; Zhang, Yanqiong; Jia, Qiang; Liu, Mingwei; Li, Defeng; Zhang, Yi; Song, Lei; Hu, Yanzhen; Xian, Minghua; Yang, Hongjun; Ding, Chen; Huang, Luqi

    2016-01-01

    Systematic investigations of complex pathological cascades during ischemic brain injury help to elucidate novel therapeutic targets against cerebral ischemia. Although some transcription factors (TFs) involved in cerebral ischemia, systematic surveys of their changes during ischemic brain injury have not been reported. Moreover, some multi-target agents effectively protected against ischemic stroke, but their mechanisms, especially the targets of TFs, are still unclear. Therefore, a comprehensive approach by integrating network pharmacology strategy and a new concatenated tandem array of consensus transcription factor response elements method to systematically investigate the target TFs critical in the protection against cerebral ischemia by a medication was first reported, and then applied to a multi-target drug, Danhong injection (DHI). High-throughput nature and depth of coverage, as well as high quantitative accuracy of the developed approach, make it more suitable for analyzing such multi-target agents. Results indicated that pre-B-cell leukemia transcription factor 1 and cyclic AMP-dependent transcription factor 1, along with six other TFs, are putative target TFs for DHI-mediated protection against cerebral ischemia. This study provides, for the first time, a systematic investigation of the target TFs critical to DHI-mediated protection against cerebral ischemia, as well as reveals more potential therapeutic targets for ischemic stroke. PMID:27431009

  4. Delivering healthcare services to children with cerebral palsy and their families: a narrative review.

    PubMed

    Hayles, Emily; Jones, Anne; Harvey, Desley; Plummer, David; Ruston, Sally

    2015-05-01

    Children with cerebral palsy have complex healthcare needs and often require complex multidisciplinary care. It is important for clinicians to understand which approaches to healthcare service delivery for this population are supported in the literature and how these should be applied in clinical practice. This narrative review aims to identify and review the evidence for current approaches to healthcare service delivery for children with cerebral palsy. Databases were searched using key terms to identify relevant research articles and grey literature from December 2011 to September 2013. Search results were screened and sorted according to inclusion and exclusion criteria. Thirty-two documents were included for evaluation and their content was analysed thematically. Three current approaches to healthcare service delivery for children with cerebral palsy identified in this narrative review were family-centred care, the World Health Organisation's International Classification of Functioning, Disability and Health, and collaborative community-based primary care. However, healthcare services for children with cerebral palsy and their families are inconsistently delivered according to these approaches and the identified guidelines or standards of care for children with cerebral palsy have limited incorporation of these approaches. Future research is required to investigate how these approaches to healthcare service delivery can be integrated into clinical practices to enable clinicians to improve services for this population. PMID:25175322

  5. Non-Linear Characterisation of Cerebral Pressure-Flow Dynamics in Humans

    PubMed Central

    Saleem, Saqib; Teal, Paul D.; Kleijn, W. Bastiaan; O’Donnell, Terrence; Witter, Trevor; Tzeng, Yu-Chieh

    2015-01-01

    Cerebral metabolism is critically dependent on the regulation of cerebral blood flow (CBF), so it would be expected that vascular mechanisms that play a critical role in CBF regulation would be tightly conserved across individuals. However, the relationships between blood pressure (BP) and cerebral blood velocity fluctuations exhibit inter-individual variations consistent with heterogeneity in the integrity of CBF regulating systems. Here we sought to determine the nature and consistency of dynamic cerebral autoregulation (dCA) during the application of oscillatory lower body negative pressure (OLBNP). In 18 volunteers we recorded BP and middle cerebral artery blood flow velocity (MCAv) and examined the relationships between BP and MCAv fluctuations during 0.03, 0.05 and 0.07Hz OLBNP. dCA was characterised using project pursuit regression (PPR) and locally weighted scatterplot smoother (LOWESS) plots. Additionally, we proposed a piecewise regression method to statistically determine the presence of a dCA curve, which was defined as the presence of a restricted autoregulatory plateau shouldered by pressure-passive regions. Results show that LOWESS has similar explanatory power to that of PPR. However, we observed heterogeneous patterns of dynamic BP-MCAv relations with few individuals demonstrating clear evidence of a dCA central plateau. Thus, although BP explains a significant proportion of variance, dCA does not manifest as any single characteristic BP-MCAv function. PMID:26421429

  6. Cerebral autoregulation and brain networks in occlusive processes of the internal carotid artery

    PubMed Central

    Avirame, Keren; Lesemann, Anne; List, Jonathan; Witte, Anja Veronica; Schreiber, Stephan Joachim; Flöel, Agnes

    2015-01-01

    Patients with unilateral occlusive processes of the internal carotid artery (ICA) show subtle cognitive deficits. Decline in cerebral autoregulation and in functional and structural integrity of brain networks have previously been reported in the affected hemisphere (AH). However, the association between cerebral autoregulation, brain networks, and cognition remains to be elucidated. Fourteen neurologically asymptomatic patients (65±11 years) with either ICA occlusion or high-grade ICA stenosis and 11 age-matched healthy controls (HC) (67±6 years) received neuropsychologic testing, transcranial Doppler sonography to assess cerebral autoregulation using vasomotor reactivity (VMR), and magnetic resonance imaging to probe white matter microstructure and resting-state functional connectivity (RSFC). Patients performed worse on memory and executive tasks when compared with controls. Vasomotor reactivity, white matter microstructure, and RSFC were lower in the AH of the patients when compared with the unaffected hemisphere and with controls. Lower VMR of the AH was associated with several ipsilateral clusters of lower white matter microstructure and lower bilateral RSFC in patients. No correlations were found between VMR and cognitive scores. In sum, impaired cerebral autoregulation was associated with reduced structural and functional connectivity in cerebral networks, indicating possible mechanisms by which severe unilateral occlusive processes of the ICA lead to cognitive decline. PMID:25388676

  7. Cerebral Palsy Gait, Clinical Importance

    PubMed Central

    TUGUI, Raluca Dana; ANTONESCU, Dinu

    2013-01-01

    ABSTRACT Cerebral palsy refers to a lesion on an immature brain, that determines permanent neurological disorders. Knowing the exact cause of the disease does not alter the treatment management. The etiology is 2-2.5/1000 births and the rate is constant in the last 40-50 years because advances in medical technologies have permitted the survival of smaller and premature new born children. Gait analysis has four directions: kinematics (represents body movements analysis without calculating the forces), kinetics (represents body moments and forces), energy consumption (measured by oximetry), and neuromuscular activity (measured by EMG). Gait analysis can observe specific deviations in a patient, allowing us to be more accurate in motor diagnoses and treatment solutions: surgery intervention, botulinum toxin injection, use of orthosis, physical kinetic therapy, oral medications, baclofen pump. PMID:24790675

  8. Malignant cerebral swelling following cranioplasty.

    PubMed

    Honeybul, S; Damodaran, O; Lind, C R P; Lee, G

    2016-07-01

    Over the past few years there have been a number of case reports and small cohort studies that have described so called "malignant" cerebral swelling following an uneventful cranioplasty procedure. The pathophysiology remains to be established however it has been suggested that it may be related to a combination of failure of autoregulation and the use of closed vacuum suction drainage. The current study presents three further patients who had had a decompressive hemicraniectomy for ischaemic stroke. If decompressive craniectomy is utilised in the management of neurological emergencies, close attention and wider reporting of this type of complication is required not only to focus attention on possible management strategies, but also to determine which patients are at most risk of this devastating complication. PMID:27189792

  9. Cerebral astroblastoma: A radiopathological diagnosis.

    PubMed

    Singh, Deepak Kumar; Singh, Neha; Singh, Ragini; Husain, Nuzhat

    2014-01-01

    Astroblastoma is a rare glial neoplasm whose histogenesis has been clarified recently. It primarily occurs in children and young adults. We are reporting a case of 12-year-old girl child who presented with features of raised intracranial tension and generalized tonic-clonic seizures. Brain magnetic resonance imaging revealed a large well-circumscribed, cystic lesion without perifocal edema, and enhancing mural nodule in right parietal region. A radiological differential diagnosis of pilocytic astrocytoma and cerebral astroblastoma was made. A complete excision was done and histologically the lesion turned out to be an astroblastoma. We review the histology, immunohistochemistry, and imaging features of astroblastoma and survey the current literature, treatment strategies, and prognostic aspects for the management of this rare neoplasm. PMID:24891904

  10. Rodent models of cerebral ischemia

    SciTech Connect

    Ginsberg, M.D.; Busto, R. )

    1989-12-01

    The use of physiologically regulated, reproducible animal models is crucial to the study of ischemic brain injury--both the mechanisms governing its occurrence and potential therapeutic strategies. Several laboratory rodent species (notably rats and gerbils), which are readily available at relatively low cost, are highly suitable for the investigation of cerebral ischemia and have been widely employed for this purpose. We critically examine and summarize several rodent models of transient global ischemia, resulting in selective neuronal injury within vulnerable brain regions, and focal ischemia, typically giving rise to localized brain infarction. We explore the utility of individual models and emphasize the necessity for meticulous experimental control of those variables that modulate the severity of ischemic brain injury.169 references.

  11. Diversity in the Strength and Structure of Unruptured Cerebral Aneurysms

    PubMed Central

    Robertson, Anne M.; Duan, Xinjie; Aziz, Khaled M.; Hill, Michael R.; Watkins, Simon C.; Cebral, Juan R.

    2015-01-01

    Intracranial aneurysms are pathological enlargements of brain arteries that are believed to arise from progressive wall degeneration and remodeling. Earlier work using classical histological approaches identified variability in cerebral aneurysm mural content, ranging from layered walls with intact endothelium and aligned smooth muscle cells, to thin, hypocellular walls. Here, we take advantage of recent advances in multiphoton microscopy, to provide novel results for collagen fiber architecture in 15 human aneurysm domes without staining or fixation as well as in 12 control cerebral arteries. For all aneurysm samples, the elastic lamina was absent and the abluminal collagen fibers had similar diameters to control arteries. In contrast, the collagen fibers on the luminal side showed great variability in both diameter and architecture ranging from dense fiber layers to sparse fiber constructs suggestive of ineffective remodeling efforts. The mechanical integrity of eight aneurysm samples was assessed using uniaxial experiments, revealing two sub-classes (i) vulnerable unruptured aneurysms (low failure stress and failure pressure), and (ii) strong unruptured aneurysms (high failure stress and failure pressure). These results suggest a need to refine the end-point of risk assessment studies that currently do not distinguish risk levels among unruptured aneurysms. We propose that a measure of wall integrity that identifies this vulnerable wall subpopulation will be useful for interpreting future biological and structural data. PMID:25632891

  12. Cerebral Amyloid Angiopathy: Emerging Concepts

    PubMed Central

    2015-01-01

    Cerebral amyloid angiopathy (CAA) involves cerebrovascular amyloid deposition and is classified into several types according to the amyloid protein involved. Of these, sporadic amyloid β-protein (Aβ)-type CAA is most commonly found in older individuals and in patients with Alzheimer's disease (AD). Cerebrovascular Aβ deposits accompany functional and pathological changes in cerebral blood vessels (CAA-associated vasculopathies). CAA-associated vasculopathies lead to development of hemorrhagic lesions [lobar intracerebral macrohemorrhage, cortical microhemorrhage, and cortical superficial siderosis (cSS)/focal convexity subarachnoid hemorrhage (SAH)], ischemic lesions (cortical infarction and ischemic changes of the white matter), and encephalopathies that include subacute leukoencephalopathy caused by CAA-associated inflammation/angiitis. Thus, CAA is related to dementia, stroke, and encephalopathies. Recent advances in diagnostic procedures, particularly neuroimaging, have enabled us to establish a clinical diagnosis of CAA without brain biopsies. Sensitive magnetic resonance imaging (MRI) methods, such as gradient-echo T2* imaging and susceptibility-weighted imaging, are useful for detecting cortical microhemorrhages and cSS. Amyloid imaging with amyloid-binding positron emission tomography (PET) ligands, such as Pittsburgh Compound B, can detect CAA, although they cannot discriminate vascular from parenchymal amyloid deposits. In addition, cerebrospinal fluid markers may be useful, including levels of Aβ40 for CAA and anti-Aβ antibody for CAA-related inflammation. Moreover, cSS is closely associated with transient focal neurological episodes (TFNE). CAA-related inflammation/angiitis shares pathophysiology with amyloid-related imaging abnormalities (ARIA) induced by Aβ immunotherapies in AD patients. This article reviews CAA and CAA-related disorders with respect to their epidemiology, pathology, pathophysiology, clinical features, biomarkers, diagnosis

  13. Cerebral vascular findings in PAPA syndrome: cerebral arterial vasculopathy or vasculitis and a posterior cerebral artery dissecting aneurysm.

    PubMed

    Khatibi, Kasra; Heit, Jeremy J; Telischak, Nicholas A; Elbers, Jorina M; Do, Huy M

    2016-08-01

    A young patient with PAPA (pyogenic arthritis, pyoderma gangrenosum, and acne) syndrome developed an unusual cerebral arterial vasculopathy/vasculitis (CAV) that resulted in subarachnoid hemorrhage from a ruptured dissecting posterior cerebral artery (PCA) aneurysm. This aneurysm was successfully treated by endovascular coil sacrifice of the affected segment of the PCA. The patient made an excellent recovery with no significant residual neurologic deficit. PMID:26122324

  14. The accuracy of automatic tracking

    NASA Technical Reports Server (NTRS)

    Kastrov, V. V.

    1974-01-01

    It has been generally assumed that tracking accuracy changes similarly to the rate of change of the curve of the measurement conversion. The problem that internal noise increases along with the signals processed by the tracking device and that tracking accuracy thus drops were considered. The main prerequisite for solution is consideration of the dependences of the output signal of the tracking device sensor not only on the measured parameter but on the signal itself.

  15. Target Tracking, Approach, and Camera Handoff for Automated Instrument Placement

    NASA Technical Reports Server (NTRS)

    Bajracharya, Max; Diaz-Calderon, Antonio; Robinson, Matthew; Powell, Mark

    2005-01-01

    This paper describes the target designation, tracking, approach, and camera handoff technologies required to achieve accurate, single-command autonomous instrument placement for a planetary rover. It focuses on robust tracking integrated with obstacle avoidance during the approach phase, and image-based camera handoff to allow vision-based instrument placement. It also provides initial results from a complete system combining these technologies with rover base placement to maximize arm manipulability and image-based instrument placement.

  16. Activity Tracking for Pilot Error Detection from Flight Data

    NASA Technical Reports Server (NTRS)

    Callantine, Todd J.; Ashford, Rose (Technical Monitor)

    2002-01-01

    This report presents an application of activity tracking for pilot error detection from flight data, and describes issues surrounding such an application. It first describes the Crew Activity Tracking System (CATS), in-flight data collected from the NASA Langley Boeing 757 Airborne Research Integrated Experiment System aircraft, and a model of B757 flight crew activities. It then presents an example of CATS detecting actual in-flight crew errors.

  17. Track-to-track association in decentralized tracking systems with feedback

    NASA Astrophysics Data System (ADS)

    Malmberg, Anders; Karlsson, Mathias

    2000-07-01

    In air combat, information advantage over the opponent is vital for the success of the operation. For that reason, modern fighter aircraft have extensive sensor suites to track other objects. In order to form a unified picture of the vicinity; all sensor information is fused. Since system modularity and high computational performance are key issues in the application, a decentralized tracking approach, where the information from the decentralized trackers is fused in a central node, is preferable. Furthermore, in order to improve the sensor tracking performance, it is often desired to feed back information to the sensors from the central node. In this paper, track-to-track association in such a decentralized tracking system with feedback is addressed. The central fusion node has to associate the sensor tracks to each other to be able to fuse them. In a system without feedback, the track-to-track association algorithm bases its conclusions on the assumption that the estimation errors of the tracks from different local trackers are not correlated. However, when information is fed back to the local trackers, this assumption is not valid, since the sensor tracks then consist of common information. System configurations that deal with this problem are proposed and tested in a fighter aircraft application. One approach is to extract the uncorrelated information from the sensor data and use that in the association process. Another approach is to keep parallel trackers in the sensors that only contain the local sensor information. Both approaches produce sensor tracks that contain the same information as the sensor tracks in a system without feedback. Also, a track-to-track association algorithm that recursively uses information from multiple time steps is proposed. The use of multiple time step data separates it from conventional track-to-track association algorithms that mostly use only current information. The result is an algorithm that improves the performance and

  18. Progressive intracranial hypertension and cerebral hypoperfusion in a fatal case of cerebral aspergilloma

    PubMed Central

    Toksvang, Linea Natalie; Plovsing, Ronni R; Berg, Ronan M G

    2014-01-01

    Summary We report a case of cerebral aspergilloma in a 25-year-old immunoincompetent man admitted to a general intensive care unit. Monitoring of intracranial pressure was instigated and revealed hour-long epochs of severe intracranial hypertension, despite a normal opening pressure, with decreases in cerebral perfusion pressure. We documented that this was associated with cerebral hypoperfusion by transcranial Doppler ultrasound. The present case illustrates that severe intracranial hypertension may evolve despite a normal opening pressure; it furthermore shows that continuous monitoring of intracranial pressure may be used to predict changes in cerebral haemodynamics in critically ill patients with neuroinfection. PMID:24907204

  19. Track Initiation for Electro-Optical Tracking of Space Objects

    NASA Astrophysics Data System (ADS)

    Xu, Z. W.; Wang, X.

    2016-03-01

    Aimed at the track initiation for the electro-optical tracking of space objects, and based on modified Hough transformation, a track initiation algorithm without prior information is proposed to realize the fully robotic identification and tracking of moving objects. The method is valid for the tracking of multi-target as well as with a non-continuous sequence. Simulation shows that the method is effective and applicable for operational usage, and is especially good for the search and discovery of new objects.

  20. Tracking of Ball and Players in Beach Volleyball Videos

    PubMed Central

    Gomez, Gabriel; Herrera López, Patricia; Link, Daniel; Eskofier, Bjoern

    2014-01-01

    This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points. PMID:25426936

  1. Tracking of ball and players in beach volleyball videos.

    PubMed

    Gomez, Gabriel; Herrera López, Patricia; Link, Daniel; Eskofier, Bjoern

    2014-01-01

    This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points. PMID:25426936

  2. Satellite (IRLS) tracking of elk

    NASA Technical Reports Server (NTRS)

    Buechner, H. K.

    1972-01-01

    The practicability of tracking free roaming animals in natural environments by satellite systems is reported. Satellite systems combine continuous tracking with simultaneous monitoring of physiological and environmental parameters through a combination of radio tracking and biotelemetric ground systems that lead to a better understanding of animal behavior and migration patterns.

  3. Footstep detection and tracking

    NASA Astrophysics Data System (ADS)

    Succi, George P.; Clapp, Daniel; Gampert, Robert; Prado, Gervasio

    2001-09-01

    Persons or vehicles moving over ground generate a succession of impacts; these soil disturbances propagate away from the source as seismic waves. These seismic waves are especially useful in detecting footsteps which cannot be detected acoustically. Footstep signals can be distinguished from other seismic sources, such as vehicles or wind noise, by their impulsive nature. Even in noisy environments, statistical measures of the seismic amplitude distribution, such as kurtosis, can be used to identify a footstep. These detection methods can be used even with single component geophones. Moreover, the seismic signal is a vector wave that can be used to track the source bearing. To do such tracking a three-component measurement is needed. If multiple sources are separated in angle, we can use this bearing information to estimate the number of walkers.

  4. Longwall shearer tracking system

    NASA Technical Reports Server (NTRS)

    Poulsen, P. D. (Inventor); Stein, R. J.; Pease, R. E.

    1984-01-01

    A tracking system for measuring and recording the movements of a longwall shearer vehicle includes an optical tracking assembly carried at one end of a desired vehicle path and a retroreflector assembly carried by the vehicle. Continuous horizontal and vertical light beams are alternately transmitted by means of a rotating Dove prism to the reflector assembly. A vertically reciprocating reflector interrupts the continuous light beams and converts these to discrete horizontal and vertical light beam images transmitted at spaced intervals along the path. A second rotating Dove prism rotates the vertical images to convert them to a second series of horizontal images while the first mentioned horizontal images are left unrotated and horizontal. The images are recorded on a film.

  5. On particle track detectors

    NASA Technical Reports Server (NTRS)

    Benton, E. V.; Gruhn, T. A.; Andrus, C. H.

    1973-01-01

    Aqueous sodium hydroxide is widely used to develop charged particle tracks in polycarbonate film, particularly Lexan. The chemical nature of the etching process for this system has been determined. A method employing ultra-violet absorbance was developed for monitoring the concentration of the etch products in solution. Using this method it was possible to study the formation of the etching solution saturated in etch products. It was found that the system super-saturates to a significant extent before precipitation occurs. It was also learned that the system approaches its equilibrium state rather slowly. It is felt that both these phenomena may be due to the presence of surfactant in the solution. In light of these findings, suggestions are given regarding the preparation and maintenance of the saturated etch solution. Two additional research projects, involving automated techniques for particle track analysis and particle identification using AgCl crystals, are briefly summarized.

  6. Chemical etching for automatic processing of integrated circuits

    NASA Technical Reports Server (NTRS)

    Kennedy, B. W.

    1981-01-01

    Chemical etching for automatic processing of integrated circuits is discussed. The wafer carrier and loading from a receiving air track into automatic furnaces and unloading onto a sending air track are included.

  7. Fast tracking hospital construction.

    PubMed

    Quirk, Andrew

    2013-03-01

    Hospital leaders should consider four factors in determining whether to fast track a hospital construction project: Expectations of project length, quality, and cost. Whether decisions can be made quickly as issues arise. Their own time commitment to the project, as well as that of architects, engineers, construction managers, and others. The extent to which they are willing to share with the design and construction teams how and why decisions are being made. PMID:23513759

  8. PARTICLE BEAM TRACKING CIRCUIT

    DOEpatents

    Anderson, O.A.

    1959-05-01

    >A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)

  9. Optical tracking telescope compensation

    NASA Technical Reports Server (NTRS)

    Gilbart, J. W.

    1973-01-01

    In order to minimize the effects of parameter variations in the dynamics of an optical tracking telescope, a model referenced parameter adaptive control system is described that - in conjunction with more traditional forms of compensation - achieves a reduction of rms pointing error by more than a factor of six. The adaptive compensation system utilizes open loop compensation, closed loop compensation, and model reference compensation to provide the precise input to force telescope axis velocity to follow the ideal velocity.

  10. A Probabilistic Cell Tracking Algorithm

    NASA Astrophysics Data System (ADS)

    Steinacker, Reinhold; Mayer, Dieter; Leiding, Tina; Lexer, Annemarie; Umdasch, Sarah

    2013-04-01

    cells is important for nowcasting. Therefore, the presented method is based on IC discharges which account for most lightning discharges and occur minutes before the first CG discharge. The cell tracking algorithm will be used as part of the integrated LoLight system. The research leading to these results has received funding from the European Union's Seventh Framework Programme managed by REA-Research Executive Agency http://ec.europa.eu/research/rea ([FP7/2007-2013] [FP7/2007-2011]) under grant agreement n° [262200].

  11. Cerebral blood flow: Physiologic and clinical aspects

    SciTech Connect

    Wood, J.H.

    1987-01-01

    This book contains 46 chapters divided among nine sections. The section titles are: Historical Perspectives; Cerebrovascular Anatomy; Cerebrovascular Physiology; Methods of Clinical Measurement; Experimental Methods; Imaging of Cerebral Circulation; Cerebrovascular Pathophysiology; Cerebrovascular Pharmacology; and Surgical and Interventional Augmentation.

  12. Genetics Home Reference: hereditary cerebral amyloid angiopathy

    MedlinePlus

    ... recurrent seizures (epilepsy). People with the Flemish and Italian types of hereditary cerebral amyloid angiopathy are prone ... amyloid angiopathy . APP gene mutations cause the Dutch, Italian, Arctic, Iowa, Flemish, and Piedmont types of this ...

  13. Transcranial cerebral oximetry in random normal subjects

    NASA Astrophysics Data System (ADS)

    Misra, Mukesh; Stark, Jennifer; Dujovny, Manuel; Alp, M. Serdar; Widman, Ronald; Ausman, James I.

    1997-08-01

    Near infrared optical spectroscopy is becoming a useful method for monitoring regional cerebral oxygenation status. The method is simple, reliable and noninvasive and the information which it provides is clinically significant in managing a growing number of neurological ailments. Use of this technique has been described previously by numerous authors. In the present study, regional cerebral oxygen saturation was measured at rest in 94 subjects randomly elected from a diverse population of individuals. This sample consisted of 38 males and 65 females, with the age ranging from 18 - 70. There were 68 light-skinned individuals and 35 with darker skin comprising various ethnic and cultural backgrounds. Mean regional cerebral hemoglobin oxygen saturation was recorded as 67.14 plus or minus 8.84%. The association of the mean regional cerebral hemoglobin oxygen saturation in various group of individuals in relationship of their age, race, sex and skin color is examined.

  14. Cerebral Sinovenous Thrombosis in Neonates and Children.

    PubMed

    Chung, Melissa G

    2016-03-01

    Investigators from Erasmus University Hospital in Belgium and Gustave-Dron Hospital and Roger-Salengro Hospital in France studied the clinical and neuroradiologic characteristics of cerebral sinovenous thrombosis (CSVT) in neonates and children. PMID:27396366

  15. Cerebral aneurysms: Formation, progression and developmental chronology

    PubMed Central

    Etminan, Nima; Buchholz, Bruce A.; Dreier, Rita; Bruckner, Peter; Torner, James C.; Steiger, Hans-Jakob; Hänggi, Daniel; Macdonald, R. Loch

    2015-01-01

    The prevalence of unruptured intracranial aneurysms (UAIs) in the general population is up to 3%. Existing epidemiological data suggests that only a small fraction of UIAs progress towards rupture over the lifetime of an individual, but the surrogates for subsequent rupture and the natural history of UIAs are discussed very controversially at present. In case of rupture of an UIA, the case-fatality is up to 50%, which therefore continues to stimulate interest in the pathogenesis of cerebral aneurysm formation and progression. Actual data on the chronological development of cerebral aneurysm has been especially difficult to obtain and, until recently, the existing knowledge in this respect is mainly derived from animal or mathematical models or short-term observational studies. Here, we highlight the current data on cerebral aneurysm formation and progression as well as a novel approach to investigate the developmental chronology of cerebral aneurysms. PMID:24323717

  16. Reversible cerebral vasoconstriction syndrome: a comprehensive update.

    PubMed

    Mehdi, Ali; Hajj-Ali, Rula A

    2014-09-01

    Reversible cerebral vasoconstriction syndrome (RCVS) is a clinico-radiological syndrome characterized by recurrent thunderclap headache, with or without neurologic symptoms, and reversible vasoconstriction of cerebral arteries. RCVS affects patients in various racial and ethnic groups and in all age groups, although most commonly in the fourth decade of life. Many conditions and exposures have been linked to RCVS, including vasoactive drugs and the peripartum period. Disturbance of the cerebral vascular tone is thought to contribute to the disease's pathophysiology. RCVS generally follows a monophasic course. Associated strokes and cerebral hemorrhages are not uncommon. In this review we will attempt to provide a comprehensive overview of RCVS, with emphasis on the controversies in the field and the newest findings in the reported literature. PMID:25138149

  17. Cerebral intraventricular echinococcosis in an adult

    PubMed Central

    Pandey, Sharad; Pandey, Deepa; Shende, Neeraj; Sahu, Anurag; Sharma, Vivek

    2015-01-01

    Background: Echinococcosis in humans occurs as a result of infection by the larval stages of taeniid cestodes of the genus echinococcus. Intracranial hydatid cysts usually develop at an intraparenchymal site. Hydatid cyst within the cerebral ventricle is quite unusual. Methods: We reviewed the literature on adult intraventricular hydatid cyst and found case reports mainly in children with an only handful of cases in adults. We reported a rare case of cerebral intraventricular (left lateral ventricle) hydatid cyst in a 21-year-old adult female. Results: Although cerebral hydatid cysts are most commonly seen in children and young adults cerebral intraventricular hydatid cyst are comparatively rarer in adults. Conclusion: The possibility of infection with Echinococcus granulosus should be included in the differential diagnosis of raised intracranial hypertension in patients from endemic areas. PMID:26392915

  18. Approximate Bayesian multibody tracking.

    PubMed

    Lanz, Oswald

    2006-09-01

    Visual tracking of multiple targets is a challenging problem, especially when efficiency is an issue. Occlusions, if not properly handled, are a major source of failure. Solutions supporting principled occlusion reasoning have been proposed but are yet unpractical for online applications. This paper presents a new solution which effectively manages the trade-off between reliable modeling and computational efficiency. The Hybrid Joint-Separable (HJS) filter is derived from a joint Bayesian formulation of the problem, and shown to be efficient while optimal in terms of compact belief representation. Computational efficiency is achieved by employing a Markov random field approximation to joint dynamics and an incremental algorithm for posterior update with an appearance likelihood that implements a physically-based model of the occlusion process. A particle filter implementation is proposed which achieves accurate tracking during partial occlusions, while in cases of complete occlusion, tracking hypotheses are bound to estimated occlusion volumes. Experiments show that the proposed algorithm is efficient, robust, and able to resolve long-term occlusions between targets with identical appearance. PMID:16929730

  19. Energy Tracking Diagrams

    NASA Astrophysics Data System (ADS)

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-02-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the Next Generation Science Standards, the primary conceptual learning goal is for learners to conserve energy as they track the transfers and transformations of energy within, into, or out of the system of interest in complex physical processes. As part of tracking energy transfers among objects, learners should (i) distinguish energy from matter, including recognizing that energy flow does not uniformly align with the movement of matter, and should (ii) identify specific mechanisms by which energy is transferred among objects, such as mechanical work and thermal conduction. As part of tracking energy transformations within objects, learners should (iii) associate specific forms with specific models and indicators (e.g., kinetic energy with speed and/or coordinated motion of molecules, thermal energy with random molecular motion and/or temperature) and (iv) identify specific mechanisms by which energy is converted from one form to another, such as incandescence and metabolism. Eventually, we may hope for learners to be able to optimize systems to maximize some energy transfers and transformations and minimize others, subject to constraints based in both imputed mechanism (e.g., objects must have motion energy in order for gravitational energy to change) and the second law of thermodynamics (e.g., heating is irreversible). We hypothesize that a subsequent goal of energy learning—innovating to meet socially relevant needs—depends crucially on the extent to which these goals have been met.

  20. Fast Track Study

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The NASA Fast Track Study supports the efforts of a Special Study Group (SSG) made up of members of the Advanced Project Management Class number 23 (APM-23) that met at the Wallops Island Management Education Center from April 28 - May 8, 1996. Members of the Class expressed interest to Mr. Vem Weyers in having an input to the NASA Policy Document (NPD) 7120.4, that will replace NASA Management Institute (NMI) 7120.4, and the NASA Program/Project Management Guide. The APM-23 SSG was tasked with assisting in development of NASA policy on managing Fast Track Projects, defined as small projects under $150 million and completed within three years. 'Me approach of the APM-23 SSG was to gather data on successful projects working in a 'Better, Faster, Cheaper' environment, within and outside of NASA and develop the Fast Track Project section of the NASA Program/Project Management Guide. Fourteen interviews and four other data gathering efforts were conducted by the SSG, and 16 were conducted by Strategic Resources, Inc. (SRI), including five interviews at the Jet Propulsion Laboratory (JPL) and one at the Applied Physics Laboratory (APL). The interviews were compiled and analyzed for techniques and approaches commonly used to meet severe cost and schedule constraints.